ARHGEF5

Gene Summary

Gene:ARHGEF5; Rho guanine nucleotide exchange factor 5
Aliases: P60, TIM, GEF5, TIM1
Location:7q35
Summary:Rho GTPases play a fundamental role in numerous cellular processes initiated by extracellular stimuli that work through G protein coupled receptors. The encoded protein may form a complex with G proteins and stimulate Rho-dependent signals. This protein may be involved in the control of cytoskeletal organization. [provided by RefSeq, Jul 2008]
Databases:VEGA, OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:rho guanine nucleotide exchange factor 5
Source:NCBIAccessed: 15 March, 2017

Ontology:

What does this gene/protein do?
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Pathways:What pathways are this gene/protein implicaed in?
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Cancer Overview

Research Indicators

Publications Per Year (1992-2017)
Graph generated 15 March 2017 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

  • Chromosome 7
  • Staging
  • NIH 3T3 Cells
  • COS Cells
  • Endometrial Cancer
  • Adenocarcinoma
  • Molecular Sequence Data
  • Rho Guanine Nucleotide Exchange Factors
  • ARNTL
  • CLOCK Proteins
  • Carcinogenesis
  • Immunoblotting
  • Nuclear Proteins
  • Promoter Regions
  • Non-Small Cell Lung Cancer
  • Immunohistochemistry
  • src-Family Kinases
  • Lung Cancer
  • Trans-Activators
  • Cyclin D1
  • ARHGEF5
  • Alternative Splicing
  • Carcinoma
  • MMP2
  • Circadian Rhythm
  • Actins
  • Guanine Nucleotide Exchange Factors
  • Neoplastic Cell Transformation
  • Amino Acid Sequence
  • ARNTL Transcription Factors
  • Base Sequence
  • Breast Cancer
  • Polymerase Chain Reaction
  • Cell Survival
  • Basic Helix-Loop-Helix Transcription Factors
  • RTPCR
  • Up-Regulation
  • Cancer Gene Expression Regulation
  • CLOCK
  • Microscopy, Confocal
Tag cloud generated 15 March, 2017 using data from PubMed, MeSH and CancerIndex

Specific Cancers (5)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: ARHGEF5 (cancer-related)

Li Z, Li N, Li F, et al.
Immune checkpoint proteins PD-1 and TIM-3 are both highly expressed in liver tissues and correlate with their gene polymorphisms in patients with HBV-related hepatocellular carcinoma.
Medicine (Baltimore). 2016; 95(52):e5749 [PubMed] Free Access to Full Article Related Publications
Immune checkpoint proteins programmed death-1 (PD-1) and T-cell immunoglobulin domain and mucin domain containing molecule-3 (TIM-3) expression and their gene polymorphisms have separately been shown to be associated with hepatitis B virus (HBV) infection and hepatocellular carcinoma (HCC). This study simultaneously examined PD-1 and TIM-3 expression in liver tissues and PD1 and TIM3 polymorphisms and analyzed their correlations in 171 patients with HBV-related HCC and 34 patients with HBV-related cirrhosis.PD-1 and TIM-3 expression in liver tissues were examined by immunohistochemistry and the genotypes of PD1 rs10204525 and TIM3 rs10053538 polymorphisms were determined using genomic DNA extracted from peripheral blood as template.Both PD-1 and TIM-3 expressions in liver infiltrating lymphocytes of HCC tumor tissues were significantly higher than those in tumor adjacent tissues or cirrhotic tissues. The elevated PD-1 and TIM-3 expressions were significantly associated with higher tumor grades. The levels between PD-1 and TIM-3 expression in tumor tissues and tumor adjacent tissues had a significant positive intercorrelation. The expressions of PD-1 and TIM-3 in tumor tissues, tumor adjacent tissues, and cirrhotic tissues were significantly associated with PD1 and TIM3 polymorphisms, with genotype AA of PD1 rs10204525 and genotypes GT+TT of TIM3 rs10053538 being associated with significantly increased PD-1 and TIM-3 expression, respectively.These findings support the potential to improve the efficiency of immune checkpoint-targeted therapy and reduce resistance to the therapy by blocking both PD-1 and TIM-3 and suggest the potential to apply the genotype determination of PD1 rs10204525 and TIM3 rs10053538 as biomarkers of immune checkpoint-directed therapies.

Feng ZM, Guo SM
Tim-3 facilitates osteosarcoma proliferation and metastasis through the NF-κB pathway and epithelial-mesenchymal transition.
Genet Mol Res. 2016; 15(3) [PubMed] Related Publications
The aim of this study was to investigate the expression of T-cell immunoglobulin mucin domain molecule-3 (Tim-3) in osteosarcoma tissues, and analyze its effect on cell proliferation and metastasis in an osteosarcoma cell line. Tim-3 mRNA and protein expression in osteosarcoma tissue was detected by reverse transcriptase-polymerase chain reaction and immunohistochemistry, respectively. Additionally, the cell viability, apoptosis rate, and invasive ability of the osteosarcoma cell line MG-63 were tested using the methyl thiazolyl tetrazolium assay, Annexin V-propidium iodide flow cytometry, and a Transwell assay, respectively, following Tim-3 interference using small interfering RNA (siRNA). We also analyzed the expression of Snail, E-cadherin, vimentin, and nuclear factor (NF)-kB in the cells by western blot. We observed that Tim-3 mRNA and protein was significantly overexpressed in osteosarcoma tissues, compared to the adjacent normal tissue (P < 0.01). Moreover, MG-63 cells transfected with the Tim-3 siRNA presented lower cell viability, a greater number of apoptotic cells, and decreased invasive ability (P < 0.01), compared to control cells. Additionally, we observed a decrease in Snail and vimentin expression, an increase in the E-cadherin level, and an increase in NF-kB p65 phosphorylation (P < 0.01) in Tim-3 siRNA-transfected MG-63 cells. Based on these results, we concluded that Tim-3 is highly expressed in osteosarcoma tissue. Moreover, we speculated that interfering in Tim-3 expression could significantly suppress osteosarcoma cell (MG-63) proliferation and metastasis via the NF-kB/Snail signaling pathway and epithelial-mesenchymal transition.

Huisman SA, Ahmadi AR, IJzermans JN, et al.
Disruption of clock gene expression in human colorectal liver metastases.
Tumour Biol. 2016; 37(10):13973-13981 [PubMed] Free Access to Full Article Related Publications
The circadian timing system controls about 40 % of the transcriptome and is important in the regulation of a wide variety of biological processes including metabolic and proliferative functions. Disruption of the circadian clock could have significant effect on human health and has an important role in the development of cancer. Here, we compared the expression levels of core clock genes in primary colorectal cancer (CRC), colorectal liver metastases (CRLM), and liver tissue within the same patient. Surgical specimens of 15 untreated patients with primary CRC and metachronous CRLM were studied. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure the expression of 10 clock genes: CLOCK, BMAL1, PER1, PER2, PER3, CRY1, CRY2, CSNK1E, TIM, TIPIN, and 2 clock-controlled genes: Cyclin-D1, and WEE1. Expression levels of 7 core clock genes were downregulated in CRLM: CLOCK (p = 0.006), BMAL1 (p = 0.003), PER1 (p = 0.003), PER2 (p = 0.002), PER3 (p < 0.001), CRY1 (p = 0.002), and CRY2 (p < 0.001). In CRC, 5 genes were downregulated: BMAL1 (p = 0.02), PER1 (p = 0.004), PER2 (p = 0.008), PER3 (p < 0.001), and CRY2 (p < 0.001). CSNK1E was upregulated in CRC (p = 0.02). Cyclin-D1 and WEE1 were both downregulated in CRLM and CRC. Related to clinicopathological factors, a significant correlation was found between low expression of CRY1 and female gender, and low PER3 expression and the number of CRLM. Our data demonstrate that the core clock is disrupted in CRLM and CRC tissue from the same patient. This disruption may be linked to altered cell-cycle dynamics and carcinogenesis.

Fooladinezhad H, Khanahmad H, Ganjalikhani-Hakemi M, Doosti A
Negative regulation of TIM-3 expression in AML cell line (HL-60) using miR-330-5p.
Br J Biomed Sci. 2016; 73(3):129-133 [PubMed] Related Publications
BACKGROUND: Uncontrolled proliferation and accumulation of leukaemic stem cells (LSCs) in bone marrow leads to acute myeloma leukaemia (AML). T cell immunoglobulin and mucine domain (TIM)-3 is a specific surface marker for LSCs and is highly expressed on LSCs compared with normal bone marrow cells, haematopoietic stem cells. Studies have indicated that microRNAs can affect AML progression through targeting different genes expressions like TIM-3. So, based on bioinformatics assessments, we predicted that miR-330-5p may highly inhibit TIM-3 expression. The purpose of the present study was to prove the silencing effect of miR-330-5p on TIM-3 gene expression in AML cell line (HL-60) in vitro.
METHODS: HL-60 cells were cultured in RPMI 1640 supplied with 10% FBS. TIM-3 expression was induced in the cells using phorbol myristate acetate (PMA). The cells were transfected with miR-330-5p and then, the gene and protein expression of TIM-3 were measured using q-RT-PCR and flow-cytometry methods, respectively.
RESULTS: The results of our bioinformatics surveys revealed that miR-330-5p has high predicted ability to silence TIM-3 gene expression. Accordingly, our experiments confirmed that miR-330-5p is able to strongly silence TIM-3 expression (98.15% silencing) in HL-60 cell line (p = 0.0001).
CONCLUSION: According to our results, miR-330-5p has a strong inhibitory effect on TIM-3 expression in AML cell line. Thus, the bioinformatics prediction of Mirwalk and Target Scan softwares for silencing effect of miR-330-5p on TIM-3 is confirmed.

Azizian A, Epping I, Kramer F, et al.
Prognostic Value of MicroRNAs in Preoperative Treated Rectal Cancer.
Int J Mol Sci. 2016; 17(4):568 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Patients with locally advanced rectal cancer are treated with preoperative chemoradiotherapy followed by surgical resection. Despite similar clinical parameters (uT2-3, uN+) and standard therapy, patients' prognoses differ widely. A possible prediction of prognosis through microRNAs as biomarkers out of treatment-naïve biopsies would allow individualized therapy options.
METHODS: Microarray analysis of 45 microdissected preoperative biopsies from patients with rectal cancer was performed to identify potential microRNAs to predict overall survival, disease-free survival, cancer-specific survival, distant-metastasis-free survival, tumor regression grade, or nodal stage. Quantitative real-time polymerase chain reaction (qPCR) was performed on an independent set of 147 rectal cancer patients to validate relevant miRNAs.
RESULTS: In the microarray screen, 14 microRNAs were significantly correlated to overall survival. Five microRNAs were included from previous work. Finally, 19 miRNAs were evaluated by qPCR. miR-515-5p, miR-573, miR-579 and miR-802 demonstrated significant correlation with overall survival and cancer-specific survival (p < 0.05). miR-573 was also significantly correlated with the tumor regression grade after preoperative chemoradiotherapy. miR-133b showed a significant correlation with distant-metastasis-free survival. miR-146b expression levels showed a significant correlation with nodal stage.
CONCLUSION: Specific microRNAs can be used as biomarkers to predict prognosis of patients with rectal cancer and possibly stratify patients' therapy if validated in a prospective study.

Poh SL, Linn YC
Immune checkpoint inhibitors enhance cytotoxicity of cytokine-induced killer cells against human myeloid leukaemic blasts.
Cancer Immunol Immunother. 2016; 65(5):525-36 [PubMed] Related Publications
We studied whether blockade of inhibitory receptors on cytokine-induced killer (CIK) cells by immune checkpoint inhibitors could increase its anti-tumour potency against haematological malignancies. CIK cultures were generated from seven normal donors and nine patients with acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL) or multiple myeloma (MM). The inhibitory receptors B and T lymphocyte attenuator, CD200 receptor, lymphocyte activation gene-3 (LAG-3) and T cell immunoglobulin and mucin-domain-containing-3 (TIM-3) were present at variable percentages in most CIK cultures, while cytotoxic T lymphocyte-associated protein 4 (CTLA-4), programmed death-1 (PD-1) and killer cell immunoglobulin-like receptors (KIR2DL1/2/3) were expressed at low level in most cultures. Without blockade, myeloid leukaemia cells were susceptible to autologous and allogeneic CIK-mediated cytotoxicity. Blockade of KIR, LAG-3, PD-1 and TIM-3 but not CTLA-4 resulted in remarkable increase in killing against these targets, even in those with poor baseline cytotoxicity. ALL and MM targets were resistant to CIK-mediated cytotoxicity, and blockade of receptors did not increase cytotoxicity to a meaningful extent. Combination of inhibitors against two receptors did not further increase cytotoxicity. Interestingly, potentiation of CIK killing by blocking antibodies was not predicted by expression of receptors on CIK and their respective ligands on the targets. Compared to un-activated T and NK cells, blockade potentiated the cytotoxicity of CIK cells to a greater degree and at a lower E:T ratio, but without significant increase in cytotoxicity against normal white cell. Our findings provide the basis for clinical trial combining autologous CIK cells with checkpoint inhibitors for patients with AML.

Wang H, Zhang X, Sun W, et al.
Activation of TIM1 induces colon cancer cell apoptosis via modulating Fas ligand expression.
Biochem Biophys Res Commun. 2016; 473(2):377-81 [PubMed] Related Publications
The pathogenesis of colon cancer is unclear. It is proposed that TIM1 has an association with human cancer. The present study aims to investigate the role of TIM1 activation in the inhibition of human colon cancer cells. In this study, human colon cancer cell line, HT29 and T84 cells were cultured. The expression of TIM1 was assessed by real time RT-PCR and Western blotting. The TIM1 on the cancer cells was activated in the culture by adding recombinant TIM4. The chromatin structure at the FasL promoter locus was assessed by chromatin immunoprecipitation. The apoptosis of the cancer cells was assessed by flow cytometry. The results showed that human colon cancer cell lines, HT29 cells and T84 cells, expressed TIM1. Activation of TIM1 by exposing the cells to TIM4 significantly increased the frequency of apoptotic colon cancer cells. The expression of FasL was increased in the cancer cells after treating by TIM4. Blocking Fas or FasL abolished the exposure to TIM4-induced T84 cell apoptosis. In conclusion, HT29 cells and T84 cells express TIM1; activation TIM1 can induce the cancer cell apoptosis. TIM1 may be a novel therapeutic target of colon cancer.

Grimm D, Lieb J, Weyer V, et al.
Organic Cation Transporter 1 (OCT1) mRNA expression in hepatocellular carcinoma as a biomarker for sorafenib treatment.
BMC Cancer. 2016; 16:94 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: The polyspecific organ cation transporter 1 (OCT1) is one of the most important active influx pumps for drugs like the kinase inhibitor sorafenib. The aim of this retrospective study was the definition of the role of intratumoral OCT1 mRNA expression in hepatocellular carcinoma (HCC) as a biomarker in systemic treatment with sorafenib.
METHODS: OCT1 mRNA expression levels were determined in biopsies from 60 primary human HCC by real time PCR. The data was retrospectively correlated with clinical parameters.
RESULTS: Intratumoral OCT1 mRNA expression is a significant positive prognostic factor for patients treated with sorafenib according to Cox regression analysis (HR 0.653, 95%-CI 0.430-0.992; p = 0.046). Under treatment with sorafenib, a survival benefit could be shown using the lower quartile of intratumoral OCT1 expression as a cut-off. Macrovascular invasion (MVI) was slightly more frequent in patients with low OCT1 mRNA expression (p = 0.037). Treatment-induced AFP response was not associated with intratumoral OCT1 mRNA expression levels (p = 0.633).
CONCLUSIONS: This study indicates a promising role for intratumoral OCT1 mRNA expression as a prognostic biomarker in therapeutic algorithms in HCC. Further prospective studies are warranted on this topic.

Ripperger T, Schlegelberger B
Acute lymphoblastic leukemia and lymphoma in the context of constitutional mismatch repair deficiency syndrome.
Eur J Med Genet. 2016; 59(3):133-42 [PubMed] Related Publications
Constitutional mismatch repair deficiency (CMMRD) syndrome is one of the rare diseases associated with a high risk of cancer. Causative mutations are found in DNA mismatch repair genes PMS2, MSH6, MSH2 or MLH1 that are well known in the context of Lynch syndrome. CMMRD follows an autosomal recessive inheritance trait and is characterized by childhood brain tumors and hematological malignancies as well as gastrointestinal cancer in the second and third decades of life. There is a high risk of multiple cancers, occurring synchronously and metachronously. In general, the prognosis is poor. About one third of CMMRD patients develop hematological malignancies as primary (sometimes the only) malignancy or as secondary neoplasm. T-cell non-Hodgkin lymphomas, mainly of mediastinal origin, are the most frequent hematological malignancies. Besides malignant diseases, non-neoplastic features are frequently observed, e.g. café-au-lait spots sometimes resembling neurofibromatosis type I, hypopigmented skin lesions, numerous adenomatous polyps, multiple pilomatricomas, or impaired immunoglobulin class switch recombination. Within the present review, we summarize previously published CMMRD patients with at least one hematological malignancy, provide an overview of steps necessary to substantiate the diagnosis of CMMRD, and refer to the recent most relevant literature.

Yang MY, Lin PM, Hsiao HH, et al.
Up-regulation of PER3 Expression Is Correlated with Better Clinical Outcome in Acute Leukemia.
Anticancer Res. 2015; 35(12):6615-22 [PubMed] Related Publications
BACKGROUND: Altered expression of circadian clock genes has been linked to various types of cancer. This study aimed to investigate whether these genes are also altered in acute myeloid leukemia (AML) and acute lymphoid leukemia (ALL).
MATERIALS AND METHODS: The expression profiles of nine circadian clock genes of peripheral blood (PB) leukocytes from patients with newly-diagnosed AML (n=41), ALL (n=23) and healthy individuals (n=51) were investigated.
RESULTS: In AML, the expression of period 1 (PER1), period 2 (PER2), period 3 (PER3), cryptochrome 1 (CRY1), cryptochrome 2 (CRY2), brain and muscle aryl hydrocarbon receptor nuclear translocator (ARNT)-like 1 (BMAL1), and timeless (TIM) was significantly down-regulated, while that of CK1ε was significantly up-regulated. In ALL, the expression of PER3 and CRY1 was significantly down-regulated, whereas those of CK1ε and TIM were significantly up-regulated. Recovery of PER3 expression was observed in both patients with AML and those with ALL who achieved remission but not in patients who relapsed after treatment.
CONCLUSION: Circadian clock genes are altered in patients with acute leukemia and up-regulation of PER3 is correlated with a better clinical outcome.

Biswas S, Holyoake D, Maughan TS
Molecular Taxonomy and Tumourigenesis of Colorectal Cancer.
Clin Oncol (R Coll Radiol). 2016; 28(2):73-82 [PubMed] Related Publications
Over the last 5 years there has been a surge in interest in the molecular classification of colorectal cancer. The effect of molecular subtyping on current treatment decisions is limited to avoidance of adjuvant 5-fluorouracil chemotherapy in stage II microsatellite unstable-high disease and avoidance of epidermal growth factor receptor-targeted antibodies in extended RAS mutant tumours. The emergence of specific novel combination therapy for the BRAF-mutant cohort and of the microsatellite unstable-high cohort as a responsive group to immune checkpoint inhibition shows the growing importance of a clinically relevant molecular taxonomy. Clinical trials such as the Medical Research Council FOCUS4 trial using biomarkers to select patients for specific therapies are currently open and testing such approaches. The integration of mutation, gene expression and pathological analyses is refining our understanding of the biological subtypes within colorectal cancer. Sharing of data sets of parallel sequencing and gene expression of thousands of cancers among independent groups has allowed the description of disease subsets and the need for a validated consensus classification has become apparent. This biological understanding of the disease is a key step forward in developing a stratified approach to patient management. The discovery of stratifiers that predict a response to existing and emerging therapies will enable better use of these treatments. Improved scientific understanding of the biological characteristics of poorly responsive subgroups will facilitate the design of novel biologically rational combinations. Novel treatment regimens, including the combination of new drugs with radiation, and the discovery and validation of their associated predictive biomarkers will gradually lead to improved outcomes from therapy.

Kikushige Y, Miyamoto T
Identification of TIM-3 as a Leukemic Stem Cell Surface Molecule in Primary Acute Myeloid Leukemia.
Oncology. 2015; 89 Suppl 1:28-32 [PubMed] Related Publications
Acute myeloid leukemia (AML) originates from self-renewing leukemic stem cells (LSCs), an ultimate therapeutic target in AML. Eradication of LSCs should be a critical and efficient therapeutic approach for the cure of AML. T-cell immunoglobulin mucin-3 (TIM-3) is expressed in most types of AML LSCs, but not in normal hematopoietic stem cells (HSCs); therefore, TIM-3 would be one of the promising therapeutic targets to specifically kill AML LSCs, sparing normal HSCs. In xenograft models reconstituted with human AML LSCs or human normal HSCs, an anti-human TIM-3 mouse antibody with cytotoxic activities exerts a potent anti-leukemic effect by targeting AML LSCs but does not affect normal human hematopoiesis in vivo. Here, we would like to introduce the recent studies on TIM-3 in normal and malignant hematopoiesis.

Zhang Q, Wang H, Wu X, et al.
TIM-4 promotes the growth of non-small-cell lung cancer in a RGD motif-dependent manner.
Br J Cancer. 2015; 113(10):1484-92 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: T-cell immunoglobulin domain and mucin domain 4 (TIM-4) is exclusively expressed in antigen-presenting cells and involved in immune regulation. However, the role of TIM-4 expressed in tumour cells remains completely unknown.
METHODS: Immunohistochemistry staining was used to examine TIM-4 or Ki-67 expression in tumour tissues. Real-time PCR or RT-PCR was performed to detect TIM-4 mRNA expression. Lung cancer cell growth and proliferation were conducted by CCK-8 assay and EdU staining. Cell cycle progression was analysed by flow cytometry. The PCNA and cell cycle-related proteins were verified by western blot. Co-IP assay was used to identify the interaction of TIM-4 and integrin αvβ3. The efficacy of TIM-4 in vivo was evaluated using xenograft tumour model.
RESULTS: The expression of TIM-4 in non-small-cell lung cancer (NSCLC) tissues was significantly higher than that of the adjacent tissues. Enhanced TIM-4 expression was negatively correlated with histological differentiation of lung carcinoma and lifespan of patients. Overexpression of TIM-4 promoted lung cancer cell growth and proliferation, and upregulated the expression of PCNA, cyclin A, cyclin B1 and cyclin D1, accompanied by accumulation of lung cancer cells in S phase. Interestingly, Arg-Gly-Asp (RGD) motif mutation abolished the effect of TIM-4 on lung cancer cells, which was further verified by tumour xenografts in mice. Furthermore, we found that TIM-4 interacted with αvβ3 integrin through RGD motif.
CONCLUSIONS: This finding suggests that TIM-4 might be a potential biomarker for NSCLC that promotes lung cancer progression by RGD motif.

Riquelme I, Tapia O, Leal P, et al.
miR-101-2, miR-125b-2 and miR-451a act as potential tumor suppressors in gastric cancer through regulation of the PI3K/AKT/mTOR pathway.
Cell Oncol (Dordr). 2016; 39(1):23-33 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Gastric cancer (GC) is a deadly malignancy worldwide. In the past, it has been shown that cellular signaling pathway alterations play a crucial role in the development of GC. In particular, deregulation of the PI3K/AKT/mTOR pathway seems to affect multiple GC functions including growth, proliferation, metabolism, motility and angiogenesis. Targeting alterations in this pathway by microRNAs (miRNAs) represents a potential therapeutic strategy, especially in inhibitor-resistant tumors. The objective of this study was to evaluate the expression of 3 pre-selected miRNAs, miR-101-2, miR-125b-2 and miR-451a, in a series of primary GC tissues and matched non-GC tissues and in several GC-derived cell lines, and to subsequently evaluate the functional role of these miRNAs.
METHODS: Twenty-five primary GC samples, 25 matched non-GC samples and 3 GC-derived cell lines, i.e., AGS, MKN28 and MKN45, were included in this study. miRNA and target gene expression levels were assessed by quantitative RT-PCR and western blotting, respectively. Subsequently, cell viability, clone formation, cell death, migration and invasion assays were performed on AGS cells.
RESULTS: miR-101-2, miR-125b-2 and miR-451a were found to be down-regulated in the primary GC tissues and the GC-derived cell lines tested. MiRNA mimic transfections significantly reduced cell viability and colony formation, increased cell death and reduced cell migration and invasion in AGS cells. We also found that exogenous expression of miR-101-2, miR-125b-2 and miR-451a decreased the expression of their putative targets MTOR, PIK3CB and TSC1, respectively.
CONCLUSIONS: Our expression analyses and in vitro functional assays suggest that miR-101-2, miR-125b-2 and miR-451a act as potential tumor suppressors in primary GCs as well as in GC-derived AGS cells.

Johung KL, Yeh N, Desai NB, et al.
Extended Survival and Prognostic Factors for Patients With ALK-Rearranged Non-Small-Cell Lung Cancer and Brain Metastasis.
J Clin Oncol. 2016; 34(2):123-9 [PubMed] Free Access to Full Article Related Publications
PURPOSE: We performed a multi-institutional study to identify prognostic factors and determine outcomes for patients with ALK-rearranged non-small-cell lung cancer (NSCLC) and brain metastasis.
PATIENTS AND METHODS: A total of 90 patients with brain metastases from ALK-rearranged NSCLC were identified from six institutions; 84 of 90 patients received radiotherapy to the brain (stereotactic radiosurgery [SRS] or whole-brain radiotherapy [WBRT]), and 86 of 90 received tyrosine kinase inhibitor (TKI) therapy. Estimates for overall (OS) and intracranial progression-free survival were determined and clinical prognostic factors were identified by Cox proportional hazards modeling.
RESULTS: Median OS after development of brain metastases was 49.5 months (95% CI, 29.0 months to not reached), and median intracranial progression-free survival was 11.9 months (95% CI, 10.1 to 18.2 months). Forty-five percent of patients with follow-up had progressive brain metastases at death, and repeated interventions for brain metastases were common. Absence of extracranial metastases, Karnofsky performance score ≥ 90, and no history of TKIs before development of brain metastases were associated with improved survival (P = .003, < .001, and < .001, respectively), whereas a single brain metastasis or initial treatment with SRS versus WBRT were not (P = .633 and .666, respectively). Prognostic factors significant by multivariable analysis were used to describe four patient groups with 2-year OS estimates of 33%, 59%, 76%, and 100%, respectively (P < .001).
CONCLUSION: Patients with brain metastases from ALK-rearranged NSCLC treated with radiotherapy (SRS and/or WBRT) and TKIs have prolonged survival, suggesting that interventions to control intracranial disease are critical. The refinement of prognosis for this molecular subtype of NSCLC identifies a population of patients likely to benefit from first-line SRS, close CNS observation, and treatment of emergent CNS disease.

Xu L, Huang Y, Tan L, et al.
Increased Tim-3 expression in peripheral NK cells predicts a poorer prognosis and Tim-3 blockade improves NK cell-mediated cytotoxicity in human lung adenocarcinoma.
Int Immunopharmacol. 2015; 29(2):635-41 [PubMed] Related Publications
T cell immunoglobulin- and mucin-domain-containing molecule-3 (Tim-3) has been shown to play an important role in mediating NK-cell function in human diseases. However, the relationship between Tim-3 expression in natural killer (NK) cells and human lung adenocarcinoma remains unclear. We therefore investigated the expression of Tim-3 in NK cells and explored the effect of Tim-3 blockade on NK cell-mediated activity in human lung adenocarcinoma. Upregulated expression of Tim-3 on CD3-CD56+ cells (P<0.05) and CD3-CD56(dim) cells (P<0.05) of patients with lung adenocarcinoma was detected by flow cytometry. Moreover, Tim-3 expression in CD3-CD56+ NK cells was higher in patients with lung adenocarcinoma with lymph node metastasis (LNM) (P<0.05) or with tumor stage T3-T4 (P<0.05). Tim-3 expression in CD56(dim) NK-cell subset was higher in patients with tumor size ≥3cm (P<0.05), or LNM (P<0.05) or with tumor stage T3-T4 (P<0.05). Further analysis showed that higher expressions of Tim-3 on both CD3-CD56+ NK cells and CD56(dim) NK-cell subset were independently correlated with shorter overall survival of patients with lung adenocarcinoma (log-rank test, P=0.0418, 0.0406, respectively). Importantly, blockade of Tim-3 signaling with anti-Tim-3 antibodies resulted in the increased cytotoxicity and IFN-γ production of peripheral NK cells from patients with lung adenocarcinoma. Our data indicate that Tim-3 expression in NK cells can function as a prognostic biomarker in human lung adenocarcinoma and support that Tim-3 could be a new target for an immunotherapeutic strategy.

Gonçalves Silva I, Gibbs BF, Bardelli M, et al.
Differential expression and biochemical activity of the immune receptor Tim-3 in healthy and malignant human myeloid cells.
Oncotarget. 2015; 6(32):33823-33 [PubMed] Free Access to Full Article Related Publications
The T cell immunoglobulin and mucin domain 3 (Tim-3) is a plasma membrane-associated receptor which is involved in a variety of biological responses in human immune cells. It is highly expressed in most acute myeloid leukaemia (AML) cells and therefore may serve as a possible target for AML therapy. However, its biochemical activities in primary human AML cells remain unclear. We therefore analysed the total expression and surface presence of the Tim-3 receptor in primary human AML blasts and healthy primary human leukocytes isolated from human blood. We found that Tim-3 expression was significantly higher in primary AML cells compared to primary healthy leukocytes. Tim-3 receptor molecules were distributed largely on the surface of primary AML cells, whereas in healthy leukocytes Tim-3 protein was mainly expressed intracellularly. In primary human AML blasts, both Tim-3 agonistic antibody and galectin-9 (a Tim-3 natural ligand) significantly upregulated mTOR pathway activity. This was in line with increased accumulation of hypoxia-inducible factor 1 alpha (HIF-1α) and secretion of VEGF and TNF-α. Similar results were obtained in primary human healthy leukocytes. Importantly, in both types of primary cells, Tim-3-mediated effects were compared with those induced by lipopolysaccharide (LPS) and stem cell factor (SCF). Tim-3 induced comparatively moderate responses in both AML cells and healthy leukocytes. However, Tim-3, like LPS, mediated the release of both TNF-α and VEGF, while SCF induced mostly VEGF secretion and did not upregulate TNF-α release.

Gutiérrez-Monreal MA, Villela L, Baltazar S, et al.
A PER3 polymorphism is associated with better overall survival in diffuse large B-cell lymphoma in Mexican population.
Cancer Biomark. 2015; 15(5):699-705 [PubMed] Related Publications
BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of malignant lymphoma. Presently, one of the most important clinical predictors of survival in DLBCL patients is the International Prognostic Index (IPI). Circadian rhythms are the approximate 24 hour biological rhythms with more than 10 genes making up the molecular clock.
OBJECTIVE: Determine if functional single nucleotide polymorphism in circadian genes may contribute to survival status in patients diagnosed with diffuse large B-cell lymphoma.
METHODS: Sixteen high-risk non-synonymous polymorphisms in circadian genes (CLOCK, CRY2, CSNK1E, CSNK2A1, NPAS2, PER1, PER2, PER3, PPP2CA, and TIM) were genotyped by screening PCR. Results were visualized by agarose gel electrophoresis and confirmed by two-direction sequencing. Clinical variables were compared between mutated and non-mutated groups. LogRank survival analysis and Kaplan-Meier method were used to calculate the overall survival.
RESULTS: PER3 rs10462020 variant showed significant difference in overall survival between patients containing mutated genotypes and those with non-mutated genotypes (p = 0.047). LDH levels (p = 0.021) and IPI score (p < 0.001) also showed differences in overall survival. No clinical differences were observed in mutated vs. non-mutated patients.
CONCLUSIONS: This work suggests a role of PER3 rs10462020 in predicting a prognosis in DLBCL overall survival of patients.

Somerville TD, Wiseman DH, Spencer GJ, et al.
Frequent Derepression of the Mesenchymal Transcription Factor Gene FOXC1 in Acute Myeloid Leukemia.
Cancer Cell. 2015; 28(3):329-42 [PubMed] Related Publications
Through in silico and other analyses, we identified FOXC1 as expressed in at least 20% of human AML cases, but not in normal hematopoietic populations. FOXC1 expression in AML was almost exclusively associated with expression of the HOXA/B locus. Functional experiments demonstrated that FOXC1 contributes to a block in monocyte/macrophage differentiation and enhances clonogenic potential. In in vivo analyses, FOXC1 collaborates with HOXA9 to accelerate significantly the onset of symptomatic leukemia. A FOXC1-repressed gene set identified in murine leukemia exhibited quantitative repression in human AML in accordance with FOXC1 expression, and FOXC1(high) human AML cases exhibited reduced morphologic monocytic differentiation and inferior survival. Thus, FOXC1 is frequently derepressed to functional effect in human AML.

Zhou E, Huang Q, Wang J, et al.
Up-regulation of Tim-3 is associated with poor prognosis of patients with colon cancer.
Int J Clin Exp Pathol. 2015; 8(7):8018-27 [PubMed] Free Access to Full Article Related Publications
Tim-3 (T cell immunoglobulin and mucin domain 3), belonging to the member of the novel Tim family, has been confirmed that it plays a critical negative role in regulating the immune responses against viral infection and carcinoma. Recently, it has also been reported that the over-expression of Tim-3 is associated with poor prognosis in solid tumors. However, the role of Tim-3 in colorectal cancer remains largely unknown. In the current study, we aim to investigate the expression of Tim-3 in colorectal carcinoma and discuss the relationship between Tim-3 expression and colon cancer prognosis, thus speculating the possible role of Tim-3 in colon cancer progression. Colon cancer tissues and paired normal tissue were obtained from 201 patients with colon cancer for preparation of tissue microarray. Tim-3 expression was evaluated by immunohistochemical staining. The Tim-3 expression level was evaluated by q-RT-PCR, western blot and immunocytochemistry in four colon cancer cell lines (HT-29, HCT116, LoVo, SW620). Tim-3 was expressed in 92.5% tumor tissue samples and 86.5% corresponding normal tissue samples. Expression of Tim-3 was significantly higher in tumor tissues than in normal tissues (P < 0.0001). Tim-3 expression in colon cancer tissues is in correlation with colon cancer lymphatic metastasis and TNM (P < 0.0001). Multivariate analysis demonstrated that Tim-3 expression could be a potential independent prognostic factor for colon cancer patients (P < 0.0001). Kaplan-Meier survival analysis result showed that patients with higher Tim-3 expression had a significantly shorter survival time than those with lower Tim-3 expression patients. Our results indicated that Tim-3 might participate in the tumorgenesis of colon cancer and Tim-3 expression might be a potential independent prognostic factor for patients with colorectal cancer.

Taipale K, Liikanen I, Juhila J, et al.
Chronic Activation of Innate Immunity Correlates With Poor Prognosis in Cancer Patients Treated With Oncolytic Adenovirus.
Mol Ther. 2016; 24(1):175-83 [PubMed] Free Access to Full Article Related Publications
Despite many clinical trials conducted with oncolytic viruses, the exact tumor-level mechanisms affecting therapeutic efficacy have not been established. Currently there are no biomarkers available that would predict the clinical outcome to any oncolytic virus. To assess the baseline immunological phenotype and find potential prognostic biomarkers, we monitored mRNA expression levels in 31 tumor biopsy or fluid samples from 27 patients treated with oncolytic adenovirus. Additionally, protein expression was studied from 19 biopsies using immunohistochemical staining. We found highly significant changes in several signaling pathways and genes associated with immune responses, such as B-cell receptor signaling (P < 0.001), granulocyte macrophage colony-stimulating factor (GM-CSF) signaling (P < 0.001), and leukocyte extravasation signaling (P < 0.001), in patients surviving a shorter time than their controls. In immunohistochemical analysis, markers CD4 and CD163 were significantly elevated (P = 0.020 and P = 0.016 respectively), in patients with shorter than expected survival. Interestingly, T-cell exhaustion marker TIM-3 was also found to be significantly upregulated (P = 0.006) in patients with poor prognosis. Collectively, these data suggest that activation of several functions of the innate immunity before treatment is associated with inferior survival in patients treated with oncolytic adenovirus. Conversely, lack of chronic innate inflammation at baseline may predict improved treatment outcome, as suggested by good overall prognosis.

Cai C, Xu YF, Wu ZJ, et al.
Tim-3 expression represents dysfunctional tumor infiltrating T cells in renal cell carcinoma.
World J Urol. 2016; 34(4):561-7 [PubMed] Related Publications
PURPOSE: Renal cell carcinoma (RCC) is the most common cancer of kidney. Evidences have shown that RCC is sensitive to various immunotherapies. Tim-3 plays a role in suppressing Th1-mediated immune responses. However, no study has yet examined the effect of Tim-3 on tumor infiltrating lymphocytes (TILs) in RCC.
METHODS: We investigated the expression and function of Tim-3 on TIL CD4+ T cells and TIL CD8+ T cells from 30 RCC patients.
RESULTS: Levels of Tim-3 were significantly increased on both TIL CD4+ T cells and TIL CD8+ T cells and were associated with higher stages of the cancer. Also, GATA-3 and interferon gamma (IFN-γ) were down-regulated, whereas T-bet was up-regulated in TIL Tim-3+ T cells, indicating that Tim-3 expression defined a population of dysfunctional TIL Th1/Tc1 cells. Mechanism analyses showed that TIL Tim-3-expressing CD8+ T cells exhibited impaired Stat5 and p38 signaling pathway. Blocking the Tim-3 pathway restored cell proliferation and increased IFN-γ production in TIL CD4+ and CD8+ T cells of RCC.
CONCLUSIONS: These results suggest that Tim-3 may be used as a novel target for increasing immune responses in RCC tumor microenvironment.

Cheng L, Ruan Z
Tim-3 and Tim-4 as the potential targets for antitumor therapy.
Hum Vaccin Immunother. 2015; 11(10):2458-62 [PubMed] Free Access to Full Article Related Publications
Both Tim-3 and Tim-4 belong to the T-cell immunoglobulin and mucin domain (Tim) gene family, which plays a critical role in immunoregulation. Tim-3 has been suggested as a negative regulator of anti-tumor immunity due to its function on inducing T cells exhaustion in cancer. In addition to its expression on exhausted T cells, Tim-3 also has been reported to up-regulate on nature killer (NK) cells and promote NK cells functionally exhausted in cancer. While Tim-3 selectively expression on most types of leukemia stem cells, it promotes the progression of acute myeloid leukemia. Recently, data from experimental models of tumor discovered that Tim-3 and Tim-4 up-regulation on tumor associated dendritic cells and macrophages attenuated the anti-tumor effects of cancer vaccines and chemotherapy. Moreover, co-blockage of Tim-3 and PD-1, Tim-3 and CD137, Tim-3 and carcinoembryonic antigen cell adhesion molecule 1 (CEACAM1) could enhance cell-mediated immunity in advanced tumor, and combined treatment with anti-Tim-3 and anti-Tim-4 mAbs further increase the efficacy of cancer vaccines. The therapeutic manipulation of TIM-3 and TIM-4 may provide a novel strategy to improve the clinical efficacy of cancer immunotherapy.

Yamoah K, Johnson MH, Choeurng V, et al.
Novel Biomarker Signature That May Predict Aggressive Disease in African American Men With Prostate Cancer.
J Clin Oncol. 2015; 33(25):2789-96 [PubMed] Free Access to Full Article Related Publications
PURPOSE: We studied the ethnicity-specific expression of prostate cancer (PC) -associated biomarkers to evaluate whether genetic/biologic factors affect ethnic disparities in PC pathogenesis and disease progression.
PATIENTS AND METHODS: A total of 154 African American (AA) and 243 European American (EA) patients from four medical centers were matched according to the Cancer of the Prostate Risk Assessment postsurgical score within each institution. The distribution of mRNA expression levels of 20 validated biomarkers reported to be associated with PC initiation and progression was compared with ethnicity using false discovery rate, adjusted Wilcoxon-Mann-Whitney, and logistic regression models. A conditional logistic regression model was used to evaluate the interaction between ethnicity and biomarkers for predicting clinicopathologic outcomes.
RESULTS: Of the 20 biomarkers examined, six showed statistically significant differential expression in AA compared with EA men in one or more statistical models. These include ERG (P < .001), AMACR (P < .001), SPINK1 (P = .001), NKX3-1 (P = .03), GOLM1 (P = .03), and androgen receptor (P = .04). Dysregulation of AMACR (P = .036), ERG (P = .036), FOXP1 (P = .041), and GSTP1 (P = .049) as well as loss-of-function mutations for tumor suppressors NKX3-1 (P = .025) and RB1 (P = .037) predicted risk of pathologic T3 disease in an ethnicity-dependent manner. Dysregulation of GOLM1 (P = .037), SRD5A2 (P = .023), and MKi67 (P = .023) predicted clinical outcomes, including 3-year biochemical recurrence and metastasis at 5 years. A greater proportion of AA men than EA men had triple-negative (ERG-negative/ETS-negative/SPINK1-negative) disease (51% v 35%; P = .002).
CONCLUSION: We have identified a subset of PC biomarkers that predict the risk of clinicopathologic outcomes in an ethnicity-dependent manner. These biomarkers may explain in part the biologic contribution to ethnic disparity in PC outcomes between EA and AA men.

Li D, Xie Z, Pape ML, Dye T
An evaluation of statistical methods for DNA methylation microarray data analysis.
BMC Bioinformatics. 2015; 16:217 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: DNA methylation offers an excellent example for elucidating how epigenetic information affects gene expression. β values and M values are commonly used to quantify DNA methylation. Statistical methods applicable to DNA methylation data analysis span a number of approaches such as Wilcoxon rank sum test, t-test, Kolmogorov-Smirnov test, permutation test, empirical Bayes method, and bump hunting method. Nonetheless, selection of an optimal statistical method can be challenging when different methods generate inconsistent results from the same data set.
RESULTS: We compared six statistical approaches relevant to DNA methylation microarray analysis in terms of false discovery rate control, statistical power, and stability through simulation studies and real data examples. Observable differences were noticed between β values and M values only when methylation levels were correlated across CpG loci. For small sample size (n=3 or 6 in each group), both the empirical Bayes and bump hunting methods showed appropriate FDR control and the highest power when methylation levels across CpG loci were independent. Only the bump hunting method showed appropriate FDR control and the highest power when methylation levels across CpG sites were correlated. For medium (n=12 in each group) and large sample sizes (n=24 in each group), all methods compared had similar power, except for the permutation test whenever the proportion of differentially methylated loci was low. For all sample sizes, the bump hunting method had the lowest stability in terms of standard deviation of total discoveries whenever the proportion of differentially methylated loci was large. The apparent test power comparisons based on raw p-values from DNA methylation studies on ovarian cancer and rheumatoid arthritis provided results as consistent as those obtained in the simulation studies. Overall, these results provide guidance for optimal statistical methods selection under different scenarios.
CONCLUSIONS: For DNA methylation studies with small sample size, the bump hunting method and the empirical Bayes method are recommended when DNA methylation levels across CpG loci are independent, while only the bump hunting method is recommended when DNA methylation levels are correlated across CpG loci. All methods are acceptable for medium or large sample sizes.

Heon EK, Wulan H, Macdonald LP, et al.
IL-15 induces strong but short-lived tumor-infiltrating CD8 T cell responses through the regulation of Tim-3 in breast cancer.
Biochem Biophys Res Commun. 2015; 464(1):360-6 [PubMed] Related Publications
IL-15 has pivotal roles in the control of CD8(+) memory T cells and has been investigated as a therapeutic option in cancer therapy. Although IL-15 and IL-2 share many functions together, including the stimulation of CD8 T cell proliferation and IFN-γ production, the different in vivo roles of IL-15 and IL-2 have been increasingly recognized. Here, we explored the different effects of IL-15 and IL-2 on tumor-infiltrating (TI) T cells from resected breast tumors. We found that neither IL-2 nor IL-15 induced intratumoral CD8 T cell proliferation by itself, but after CD3/CD28-stimulation, IL-15 induced significantly higher proliferation than IL-2 during early time points, at day 2, day 3 and day 6. However, the IL-15-induced proliferation leveled off at day 9 and day 12, whereas IL-2 induced lower but progressive proliferation at each time point. Furthermore, IL-15 caused an early and robust increase of IFN-γ in the supernatant of TI cell cultures, which diminished at later time points, while the IL-2-induced IFN-γ production remained constant over time. In addition, the IL-15-costimulated CD8 T cells presented higher frequencies of apoptotic cells. The diminishing IL-15-induced response was possibly due to regulatory and/or exhaustion mechanisms. We did not observe increased IL-10 or PD-1 upregulation, but we have found an increase of Tim-3 upregulation on IL-15-, but not IL-2-stimulated cells. Blocking Tim-3 function using anti-Tim-3 antibodies resulted in increased IL-15-induced proliferation and IFN-γ production for a prolonged period of time, whereas adding Tim-3 ligand galectin 9 led to reduced proliferation and IFN-γ production. Our results suggest that IL-15 in combination of Tim-3 blocking antibodies could potentially act as an IL-2 alternative in tumor CD8 T cell expansion in vitro, a crucial step in adoptive T cell therapy.

Tan Z, Liu R, Zheng L, et al.
Cerebrospinal fluid protein dynamic driver network: At the crossroads of brain tumorigenesis.
Methods. 2015; 83:36-43 [PubMed] Related Publications
To get a better understanding of the ongoing in situ environmental changes preceding the brain tumorigenesis, we assessed cerebrospinal fluid (CSF) proteome profile changes in a glioma rat model in which brain tumor invariably developed after a single in utero exposure to the neurocarcinogen ethylnitrosourea (ENU). Computationally, the CSF proteome profile dynamics during the tumorigenesis can be modeled as non-smooth or even abrupt state changes. Such brain tumor environment transition analysis, correlating the CSF composition changes with the development of early cellular hyperplasia, can reveal the pathogenesis process at network level during a time before the image detection of the tumors. In our controlled rat model study, matched ENU- and saline-exposed rats' CSF proteomics changes were quantified at approximately 30, 60, 90, 120, 150 days of age (P30, P60, P90, P120, P150). We applied our transition-based network entropy (TNE) method to compute the CSF proteome changes in the ENU rat model and test the hypothesis of the critical transition state prior to impending hyperplasia. Our analysis identified a dynamic driver network (DDN) of CSF proteins related with the emerging tumorigenesis progressing from the non-hyperplasia state. The DDN associated leading network CSF proteins can allow the early detection of such dynamics before the catastrophic shift to the clear clinical landmarks in gliomas. Future characterization of the critical transition state (P60) during the brain tumor progression may reveal the underlying pathophysiology to device novel therapeutics preventing tumor formation. More detailed method and information are accessible through our website at http://translationalmedicine.stanford.edu.

Webb JR, Milne K, Nelson BH
PD-1 and CD103 Are Widely Coexpressed on Prognostically Favorable Intraepithelial CD8 T Cells in Human Ovarian Cancer.
Cancer Immunol Res. 2015; 3(8):926-35 [PubMed] Related Publications
αE(CD103)β7 is a TGFβ-regulated integrin that mediates retention of lymphocytes in peripheral tissues by binding to E-cadherin expressed on epithelial cells. We recently reported that αE(CD103)β7 specifically demarcates intraepithelial CD8(+) tumor-infiltrating lymphocytes (CD8 TIL) in ovarian cancer and that CD103(+) TIL have a surface profile consistent with an active effector phenotype (HLA-DR(+), Ki67(+), and CD127(lo)). These findings led us to hypothesize that, over time, CD103-mediated retention of CD8 TIL within the tumor epithelium might result in chronic stimulation by tumor antigen, which in turn might lead to an exhausted phenotype. To investigate this possibility, we evaluated PD-1 expression in a large cohort of ovarian tumors (N = 489) with known CD103(+) TIL content. PD-1(+) cells were present in 38.5% of high-grade serous carcinomas (HGSC), but were less prevalent in other histologic subtypes. PD-1(+) TIL were strongly associated with increased disease-specific survival in HGSC (HR, 0.4864; P = 0.0007). Multicolor immunohistochemistry and flow cytometry revealed a high degree of PD-1 and CD103 coexpression, specifically within the CD8 TIL compartment. PD-1(+)CD103(+) CD8 TIL were quiescent when assessed directly ex vivo yet were capable of robust cytokine production after pharmacologic stimulation. Moreover, they showed negligible expression of additional exhaustion-associated markers, including TIM-3, CTLA-4, and LAG-3. Thus, as hypothesized, CD103(+) CD8 TIL express PD-1 and appear quiescent in the tumor microenvironment. However, these cells retain functional competence and demonstrate strong prognostic significance. We speculate that, after standard treatment, PD-1(+)CD103(+) CD8 TIL might regain functional antitumor activity, an effect that potentially could be augmented by immune modulation.

Sehgal K, Das R, Zhang L, et al.
Clinical and pharmacodynamic analysis of pomalidomide dosing strategies in myeloma: impact of immune activation and cereblon targets.
Blood. 2015; 125(26):4042-51 [PubMed] Free Access to Full Article Related Publications
In preclinical studies, pomalidomide mediated both direct antitumor effects and immune activation by binding cereblon. However, the impact of drug-induced immune activation and cereblon/ikaros in antitumor effects of pomalidomide in vivo is unknown. Here we evaluated the clinical and pharmacodynamic effects of continuous or intermittent dosing strategies of pomalidomide/dexamethasone in lenalidomide-refractory myeloma in a randomized trial. Intermittent dosing led to greater tumor reduction at the cost of more frequent adverse events. Both cohorts experienced similar event-free and overall survival. Both regimens led to a distinct pattern but similar degree of mid-cycle immune activation, manifested as increased expression of cytokines and lytic genes in T and natural killer (NK) cells. Pomalidomide induced poly-functional T-cell activation, with increased proportion of coinhibitory receptor BTLA(+) T cells and Tim-3(+) NK cells. Baseline levels of ikaros and aiolos protein in tumor cells did not correlate with response or survival. Pomalidomide led to rapid decline in Ikaros in T and NK cells in vivo, and therapy-induced activation of CD8(+) T cells correlated with clinical response. These data demonstrate that pomalidomide leads to strong and rapid immunomodulatory effects involving both innate and adaptive immunity, even in heavily pretreated multiple myeloma, which correlates with clinical antitumor effects. This trial was registered at www.clinicaltrials.gov as #NCT01319422.

Sønderstrup IM, Nygård SB, Poulsen TS, et al.
Topoisomerase-1 and -2A gene copy numbers are elevated in mismatch repair-proficient colorectal cancers.
Mol Oncol. 2015; 9(6):1207-17 [PubMed] Related Publications
INTRODUCTION: Topoisomerase 1 (TOP1) and 2A (TOP2A) are potential predictive biomarkers for irinotecan and anthracycline treatment, respectively, in colorectal cancer (CRC), and we have recently reported a high frequency of gene gain of the TOP1 and TOP2A genes in CRC. Furthermore, Mismatch Repair (MMR) subtypes of CRC have been associated with benefit from adjuvant chemotherapy of primary CRC. Given the involvement of the topoisomerase enzymes in DNA replication and repair, we raised the hypothesis that an association may exist between TOP gene copy numbers and MMR proficiency/deficiency in CRC.
MATERIAL AND METHODS: Test cohort: FISH analysis with an in-house TOP1/CEN20 probe mix and a commercially available TOP2A/CEN17 (Dako, Glostrup, Denmark) probe mix was performed on archival formalin fixed paraffin embedded (FFPE) tissue samples from 18 patients with proficient MMR (pMMR) CRC and 18 patients with deficient MMR (dMMR) CRC. TOP1 and TOP2A gene copy numbers and their ratios per nucleus were correlated with MMR status using the Mann-Whitney test. Validation cohort: FFPE samples from 154 patients with primary stage III CRC (originally included in the RANX05 study) were classified according to MMR status by immunohistochemical analysis using validated antibodies for MLH1, MLH2, MSH6 and PMS2, and information on TOP1, CEN20, TOP2A and CEN17 status was previously published for this cohort.
RESULTS: The observed TOP1 gene copy numbers in the 36 CRC test cohort were significantly greater (p < 0.01) in the pMMR subgroup (mean: 3.84, SD: 2.03) than in the dMMR subgroup (mean: 1.50, SD: 0.12). Similarly, the TOP2A copy numbers were significantly greater (p < 0.01) in the pMMR subgroup (mean: 1.99, SD: 0.52) than in the dMMR subgroup (mean: 1.52, SD: 0.10). These findings were confirmed in the validation cohort, where in the pMMR subgroup 51% had ≥2 extra TOP1 copies per cell, while all tumors classified as dMMR had diploid TOP1 status and mean TOP2A copy numbers were 2.30 (SD: 1.36) and 1.80 (SD: 0.31) (p = 0.01) in the pMMR subgroup vs. dMMR subgroup, respectively.
DISCUSSION AND CONCLUSION: Our results show that TOP1 and TOP2A gene copy numbers are increased in the pMMR subgroup. We propose that this preference may reflect a selective pressure to gain and/or maintain the gained extra copies of topoisomerase genes whose products are required to cope with high replication stress present in the pMMR tumors, thereby providing a survival advantage selectively in pMMR tumors. Future studies should test this concept and explore potential differences between pMMR and dMMR tumors in response to Top1 and Top2 inhibitors.

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