TSPO

Gene Summary

Gene:TSPO; translocator protein
Aliases: DBI, IBP, MBR, PBR, PBS, BPBS, BZRP, PKBS, PTBR, mDRC, pk18
Location:22q13.2
Summary:Present mainly in the mitochondrial compartment of peripheral tissues, the protein encoded by this gene interacts with some benzodiazepines and has different affinities than its endogenous counterpart. The protein is a key factor in the flow of cholesterol into mitochondria to permit the initiation of steroid hormone synthesis. Alternatively spliced transcript variants have been reported; one of the variants lacks an internal exon and is considered non-coding, and the other variants encode the same protein. [provided by RefSeq, Feb 2012]
Databases:OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:translocator protein
Source:NCBIAccessed: 29 August, 2019

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 (1994-2019)
Graph generated 29 August 2019 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.

Tag cloud generated 29 August, 2019 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: TSPO (cancer-related)

Cao C, Wang Q, Li Q, et al.
Development and Preliminary Clinical Application of Circulating Tumor Cell Detection System for Prostate Cancer.
J Biomed Nanotechnol. 2019; 15(3):612-620 [PubMed] Related Publications
Real-time detection of circulating tumor cell (CTC) markers that are constantly changing and renewing during disease progression is of great significance for the timely regimen switch or individualized target therapy. The abnormally expressed special AT-rich sequence binding protein 1 (SATB1), a nuclear matrix attachment region binding protein, in various tumors, promotes the growth and metastasis of tumor cells by regulating gene expression. In this paper, a CTC detection system for prostate cancer (PCa) was developed on the basis of epithelial cell adhesion molecule (EpCAM)-targeted immunomagnetic separation and CK-FITC and SATB-1-APC immunofluorescence assay, and the recovery rate of tumor cells in PBS and simulated whole blood by this system was detected. Subsequently, we isolated, identified, and counted SATB-1 ositive CTCs in the peripheral blood and urine samples of 60 tumor-bearing nude mice, 5 healthy volunteers and 13 PCa patients. Combined with the clinicopathological factors, the clinical value of the system was analyzed, and the possibility of SATB-1-positive CTCs in the diagnosis of PCa was evaluated. The results showed that the CTC sorting and identification system for prostate cancer constructed in this study had a recovery rate of more than 85% for CTC in PBS, urine and blood simulation samples. The expression level of SATB-1 was different in different PCa cell lines, which was relatively high in the highly invasive PCa DU-145 cell line. The expression of SATB-1 in CTCs in the blood samples of PCa patients with different clinical characteristics and in the urine samples of a few PCa patients with bone metastases were different, and the detection sensitivity of peripheral blood was higher than that of urine. This study has important clinical reference value for the early diagnosis of PCa and the evaluation of bone metastasis based on the CTC counting and the SATB-1 expression in CTCs.

Ruffalo M, Bar-Joseph Z
Protein interaction disruption in cancer.
BMC Cancer. 2019; 19(1):370 [PubMed] Related Publications
BACKGROUND: Most methods that integrate network and mutation data to study cancer focus on the effects of genes/proteins, quantifying the effect of mutations or differential expression of a gene and its neighbors, or identifying groups of genes that are significantly up- or down-regulated. However, several mutations are known to disrupt specific protein-protein interactions, and network dynamics are often ignored by such methods. Here we introduce a method that allows for predicting the disruption of specific interactions in cancer patients using somatic mutation data and protein interaction networks.
METHODS: We extend standard network smoothing techniques to assign scores to the edges in a protein interaction network in addition to nodes. We use somatic mutations as input to our modified network smoothing method, producing scores that quantify the proximity of each edge to somatic mutations in individual samples.
RESULTS: Using breast cancer mutation data, we show that predicted edges are significantly associated with patient survival and known ligand binding site mutations. In-silico analysis of protein binding further supports the ability of the method to infer novel disrupted interactions and provides a mechanistic explanation for the impact of mutations on key pathways.
CONCLUSIONS: Our results show the utility of our method both in identifying disruptions of protein interactions from known ligand binding site mutations, and in selecting novel clinically significant interactions. Supporting website with software and data: https://www.cs.cmu.edu/~mruffalo/mut-edge-disrupt/ .

Pradier MF, Reis B, Jukofsky L, et al.
Case-control Indian buffet process identifies biomarkers of response to Codrituzumab.
BMC Cancer. 2019; 19(1):278 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Codrituzumab, a humanized monoclonal antibody against Glypican-3 (GPC3), which is expressed in hepatocellular carcinoma (HCC), was tested in a randomized phase II trial in advanced HCC patients who had failed prior systemic therapy. Biomarker analysis was performed to identify a responder population that benefits from treatment.
METHODS: A novel statistical method based on the Indian buffet process (IBP) was used to identify biomarkers predictive of response to treatment with Codrituzumab. The IBP is a novel method that allows flexibility in analysis design, and which is sensitive to slight, but meaningful between-group differences in biomarkers in very complex datasets RESULTS: The IBP model identified several subpopulations of patients having defined biomarker values. Tumor necrosis and viable cell content in the tumor were identified as prognostic markers of disease progression, as were the well-known HCC prognostic markers of disease progression, alpha-fetoprotein and Glypican-3 expression. Predictive markers of treatment response included natural killer (NK) cell surface markers and parameters influencing NK cell activity, all related to the mechanism of action of this drug CONCLUSIONS: The Indian buffet process can be effectively used to detect statistically significant signals with high sensitivity in complex and noisy biological data TRIAL REGISTRATION: NCT01507168 , January 6, 2012.

Su H, Tao T, Yang Z, et al.
Circular RNA cTFRC acts as the sponge of MicroRNA-107 to promote bladder carcinoma progression.
Mol Cancer. 2019; 18(1):27 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Circular RNA (circRNA) represents a broad and diverse endogenous RNAs that can regulate gene expression in cancer. However, the regulation and function of bladder cancer (BC) circRNAs remain largely unknown.
METHODS: Here we generated circRNA microarray data from three BC tissues and paired non-cancerous matched tissues, and detected circular RNA-cTFRC up-regulated and correlated with tumor grade and poor survival rate of BC patients. We subsequently performed functional analyses in cell lines and an animal model to support clinical findings. Mechanistically, we demonstrated that cTFRC could directly bind to miR-107 and relieve suppression for target TFRC expression.
RESULTS: We detected circular RNA-cTFRC up-regulated and correlated with tumor grade and poor survival rate of BC patients. Knock down of cTFRC inhibited invasion and proliferation of BC cell lines in vitro and tumor growth in vivo. Furthermore, the expression of cTFRC correlated with TFRC and negatively correlated with miR-107 both in BC cell lines and BC clinical samples. In addition, up-regulation of cTFRC promoted TFRC expression and contributed to an epithelial to mesenchymal transition phenotype in BC cells. Finally, we found that cTFRC acts as a competing endogenous RNA (ceRNA) for miR-107 to regulate TFRC expression.
CONCLUSIONS: cTFRC may exert regulatory functions in BC and may be a potential marker of BC diagnosis or progression.

Jiang X, Finucane HK, Schumacher FR, et al.
Shared heritability and functional enrichment across six solid cancers.
Nat Commun. 2019; 10(1):431 [PubMed] Free Access to Full Article Related Publications
Quantifying the genetic correlation between cancers can provide important insights into the mechanisms driving cancer etiology. Using genome-wide association study summary statistics across six cancer types based on a total of 296,215 cases and 301,319 controls of European ancestry, here we estimate the pair-wise genetic correlations between breast, colorectal, head/neck, lung, ovary and prostate cancer, and between cancers and 38 other diseases. We observed statistically significant genetic correlations between lung and head/neck cancer (r

Oh HN, Oh KB, Lee MH, et al.
JAK2 regulation by licochalcone H inhibits the cell growth and induces apoptosis in oral squamous cell carcinoma.
Phytomedicine. 2019; 52:60-69 [PubMed] Related Publications
BACKGROUND: Licochalconce (LC) H is an artificial compound in the course of synthesizing LCC in 2013. So far, few studies on the effects of LCH have been found in the literature. Despite progress in treatment modalities for oral cancer, the cure from cancer has still limitations.
PURPOSE: The effects of LCH were investigated on human oral squamous cell carcinoma (OSCC) cells to elucidate its mechanisms.
STUDY DESIGN: We explored the mechanism of action of LCH by which it could have effects on JAK2/STAT3 signaling pathway.
METHODS: To confirm LCH anti-cancer effect, analyzed were MTT assay, DAPI staining, soft agar, kinase assay, molecular docking simulation, flow cytometry and Western blotting analysis.
RESULTS: According to docking and molecular dynamics simulations, the predicted pose of the complex LCH and JAK2 seems reasonable and LCH is strongly bound to active JAK2 with opened activation loop. The LCH inhibitor is surrounded by specific ATP-binding pocket in which it is stabilized by forming hydrogen bonds and hydrophobic interactions. It is shown that LCH plays as a competitive inhibitor in an active state of JAK2. LCH caused a dose-dependent decrease in phosphorylation of JAK2 and STAT3. More interestingly, LCH suppressed JAK2 kinase activity in vitro by its direct binding to the JAK2. LCH significantly inhibited the JAK2/STAT3 signaling pathway, causing the down-regulation of target genes such as Bcl-2, survivin, cyclin D1, p21 and p27. In addition, LCH inhibited cell proliferation and colony formation of OSCC cells in a dose- and time-dependent manner, as well as induction of cell apoptosis through extrinsic and intrinsic pathway. The induction of apoptosis in OSCC cells by LCH was evident in the increased production of ROS, loss of mitochondrial membrane potential, release of cyto c, variation of apoptotic proteins and activation of caspase cascade.
CONCLUSION: LCH not only induces apoptosis in OSCC cells through the JAK/STAT3 signaling pathway but also inhibits cell growth. It is proposed that LCH has a promising use for the chemotherapeutic agent of oral cancer.

Carrillo E, Ramírez-Rivera S, Bernal G, et al.
Water-soluble Ru(II)-anethole compounds with promising cytotoxicity toward the human gastric cancer cell line AGS.
Life Sci. 2019; 217:193-201 [PubMed] Related Publications
AIMS: Ruthenium-based compounds exhibit critical biochemical properties making them suitable for diverse pharmacological applications. The aim of this work was to study the anticancer effects of three ruthenium complexes on a human gastric cancer cell line.
MAIN METHODS: We synthetized three [Ru(η
KEY FINDINGS: Compound 3 exhibited the highest cytotoxicity (IC
SIGNIFICANCE: Our data suggests that compound 3 may be an interesting anticancer molecule for the treatment of gastric cancer.

Majkowska-Pilip A, Koźmiński P, Wawrzynowska A, et al.
Application of Neurokinin-1 Receptor in Targeted Strategies for Glioma Treatment. Part I: Synthesis and Evaluation of Substance P Fragments Labeled with
Molecules. 2018; 23(10) [PubMed] Free Access to Full Article Related Publications
Gliomas, particularly WHO grade IV glioblastoma multiforme, are one of the most common and aggressive primary tumors of the central nervous system. The neuropeptide, substance P (SP), is the physiological ligand of the neurokinin-1 (NK-1) receptor that is consistently overexpressed in glioblastoma cells. The aim of this work was to study physico-chemical and biological properties of different SP analogues labeled with technetium-99m and lutetium-177 radionuclides. The synthesized compounds were characterized in vitro by partition coefficients (log

Jian Z, Cheng T, Zhang Z, et al.
Glycemic Variability Promotes Both Local Invasion and Metastatic Colonization by Pancreatic Ductal Adenocarcinoma.
Cell Mol Gastroenterol Hepatol. 2018; 6(4):429-449 [PubMed] Free Access to Full Article Related Publications
Background & Aims: Although nearly half of pancreatic ductal adenocarcinoma (PDAC) patients have diabetes mellitus with episodes of hyperglycemia, its tumor microenvironment is hypoglycemic. Thus, it is crucial for PDAC cells to develop adaptive mechanisms dealing with oscillating glucose levels. So far, the biological impact of such glycemic variability on PDAC biology remains unknown.
Methods: Murine PDAC cells were cultured in low- and high-glucose medium to investigate the molecular, biochemical, and metabolic influence of glycemic variability on tumor behavior. A set of in vivo functional assays including orthotopic implantation and portal and tail vein injection were used. Results were further confirmed on tissues from PDAC patients.
Results: Glycemic variability has no significant effect on PDAC cell proliferation. Hypoglycemia is associated with local invasion and angiogenesis, whereas hyperglycemia promotes metastatic colonization. Increased metastatic colonization under hyperglycemia is due to increased expression of runt related transcription factor 3 (Runx3), which further activates expression of collagen, type VI, alpha 1 (Col6a1), forming a glycemic pro-metastatic pathway. Through epigenetic machinery, retinoic acid receptor beta (Rarb) expression fluctuates according to glycemic variability, acting as a critical sensor relaying the glycemic signal to Runx3/Col6a1. Moreover, the signal axis of Rarb/Runx3/Col6a1 is pharmaceutically accessible to a widely used antidiabetic substance, metformin, and Rar modulator. Finally, PDAC tissues from patients with diabetes show an increased expression of COL6A1.
Conclusions: Glycemic variability promotes both local invasion and metastatic colonization of PDAC. A pro-metastatic signal axis Rarb/Runx3/Col6a1 whose activity is controlled by glycemic variability is identified. The therapeutic relevance of this pathway needs to be explored in PDAC patients, especially in those with diabetes.

Zhang J, Zhang S, Liu Y, et al.
Combined CB2 receptor agonist and photodynamic therapy synergistically inhibit tumor growth in triple negative breast cancer.
Photodiagnosis Photodyn Ther. 2018; 24:185-191 [PubMed] Article available free on PMC after 01/12/2019 Related Publications
Triple negative breast cancer (TNBC) is the deadliest form of breast cancer because it is more aggressive, diagnosed at later stage and more likely to develop local and systemic recurrence. Many patients do not experience adequate tumor control after current clinical treatments involving surgical removal, chemotherapy and/or radiotherapy, leading to disease progression and significantly decreased quality of life. Here we report a new combinatory therapy strategy involving cannabinoid-based medicine and photodynamic therapy (PDT) for the treatment of TNBC. This combinatory therapy targets two proteins upregulated in TNBC: the cannabinoid CB2 receptor (CB

Zhu P, Wu J, Wang Y, et al.
LncGata6 maintains stemness of intestinal stem cells and promotes intestinal tumorigenesis.
Nat Cell Biol. 2018; 20(10):1134-1144 [PubMed] Related Publications
The intestinal epithelium harbours remarkable self-renewal capacity that is driven by Lgr5

Chou YC, Chang MY, Lee HT, et al.
Phenethyl Isothiocyanate Inhibits In Vivo Growth of Xenograft Tumors of Human Glioblastoma Cells.
Molecules. 2018; 23(9) [PubMed] Article available free on PMC after 01/12/2019 Related Publications
Phenethyl isothiocyanate (PEITC) from cruciferous vegetables can inhibit the growth of various human cancer cells. In previous studies, we determined that PEITC inhibited the in vitro growth of human glioblastoma GBM 8401 cells by inducing apoptosis, inhibiting migration and invasion, and altering gene expression. Nevertheless, there are no further in vivo reports disclosing whether PEITC can suppress the growth of glioblastoma. Therefore, in this study we investigate the anti-tumor effects of PEITC in a xenograft model of glioblastoma in nude mice. Thirty nude mice were inoculated subcutaneously with GBM 8401 cells. Mice with one palpable tumor were divided randomly into three groups: control, PEITC-10, and PEITC-20 groups treated with 0.1% dimethyl sulfoxide (DMSO), and 10 and 20 μmole PEITC/100 μL PBS daily by oral gavage, respectively. PEITC significantly decreased tumor weights and volumes of GBM 8401 cells in mice, but did not affect the total body weights of mice. PEITC diminished the levels of anti-apoptotic proteins MCL-1 (myeloid cell leukemia 1) and XIAP (X-linked inhibitor of apoptosis protein) in GBM 8401 cells. PEITC enhanced the levels of caspase-3 and Bax in GBM 8401 cells. The growth of glioblastoma can be suppressed by the biological properties of PEITC in vivo. These effects might support further investigations into the potential use of PEITC as an anticancer drug for glioblastoma.

Jonchere V, Marisa L, Greene M, et al.
Identification of Positively and Negatively Selected Driver Gene Mutations Associated With Colorectal Cancer With Microsatellite Instability.
Cell Mol Gastroenterol Hepatol. 2018; 6(3):277-300 [PubMed] Article available free on PMC after 01/12/2019 Related Publications
Background & Aims: Recent studies have shown that cancers arise as a result of the positive selection of driver somatic events in tumor DNA, with negative selection playing only a minor role, if any. However, these investigations were concerned with alterations at nonrepetitive sequences and did not take into account mutations in repetitive sequences that have very high pathophysiological relevance in the tumors showing microsatellite instability (MSI) resulting from mismatch repair deficiency investigated in the present study.
Methods: We performed whole-exome sequencing of 47 MSI colorectal cancers (CRCs) and confirmed results in an independent cohort of 53 MSI CRCs. We used a probabilistic model of mutational events within microsatellites, while adapting pre-existing models to analyze nonrepetitive DNA sequences. Negatively selected coding alterations in MSI CRCs were investigated for their functional and clinical impact in CRC cell lines and in a third cohort of 164 MSI CRC patients.
Results: Both positive and negative selection of somatic mutations in DNA repeats was observed, leading us to identify the expected true driver genes associated with the MSI-driven tumorigenic process. Several coding negatively selected MSI-related mutational events (n = 5) were shown to have deleterious effects on tumor cells. In the tumors in which deleterious MSI mutations were observed despite the negative selection, they were associated with worse survival in MSI CRC patients (hazard ratio, 3; 95% CI, 1.1-7.9;
Conclusions: The present results identify the positive and negative driver somatic mutations acting in MSI-driven tumorigenesis, suggesting that genomic instability in MSI CRC plays a dual role in achieving tumor cell transformation. Exome sequencing data have been deposited in the European genome-phenome archive (accession: EGAS00001002477).

Means AL, Freeman TJ, Zhu J, et al.
Epithelial Smad4 Deletion Up-Regulates Inflammation and Promotes Inflammation-Associated Cancer.
Cell Mol Gastroenterol Hepatol. 2018; 6(3):257-276 [PubMed] Article available free on PMC after 01/12/2019 Related Publications
Background & Aims: Chronic inflammation is a predisposing condition for colorectal cancer. Many studies to date have focused on proinflammatory signaling pathways in the colon. Understanding the mechanisms that suppress inflammation, particularly in epithelial cells, is critical for developing therapeutic interventions. Here, we explored the roles of transforming growth factor β (TGFβ) family signaling through SMAD4 in colonic epithelial cells.
Methods: The
Results: Dextran sodium sulfate treatment was sufficient to drive carcinogenesis in mice lacking colonic
Conclusions: TGFβ suppresses the expression of proinflammatory genes in the colon epithelium, and loss of its downstream mediator, SMAD4, is sufficient to initiate inflammation-driven colon cancer. Transcript profiling: GSE100082.

Makjaroen J, Somparn P, Hodge K, et al.
Comprehensive Proteomics Identification of IFN-λ3-regulated Antiviral Proteins in HBV-transfected Cells.
Mol Cell Proteomics. 2018; 17(11):2197-2215 [PubMed] Article available free on PMC after 01/11/2019 Related Publications
Interferon lambda (IFN-λ) is a relatively unexplored, yet promising antiviral agent. IFN-λ has recently been tested in clinical trials of chronic hepatitis B virus infection (CHB), with the advantage that side effects may be limited compared with IFN-α, as IFN-λ receptors are found only in epithelial cells. To date, IFN-λ's downstream signaling pathway remains largely unelucidated, particularly via proteomics methods. Here, we report that IFN-λ3 inhibits HBV replication in HepG2.2.15 cells, reducing levels of both HBV transcripts and intracellular HBV DNA. Quantitative proteomic analysis of HBV-transfected cells was performed following 24-hour IFN-λ3 treatment, with parallel IFN-α2a and PBS treatments for comparison using a dimethyl labeling method. The depth of the study allowed us to map the induction of antiviral proteins to multiple points of the viral life cycle, as well as facilitating the identification of antiviral proteins not previously known to be elicited upon HBV infection (

Yang Z, Zhang R, Ge Y, et al.
Somatic FGFR3 Mutations Distinguish a Subgroup of Muscle-Invasive Bladder Cancers with Response to Neoadjuvant Chemotherapy.
EBioMedicine. 2018; 35:198-203 [PubMed] Article available free on PMC after 01/11/2019 Related Publications
The administration of neoadjuvant chemotherapy (NAC) preceding radical cystectomy benefits overall survival for patients with muscle-invasive bladder cancer (MIBC). However, the relationship between the genetic profiling of MIBC and NAC response remains unclear. Here, a mutation panel of six cancer-associated genes (TSC1, FGFR3, TERT, TP53, PIK3CA and ERBB2) and an immunohistochemistry (IHC) panel containing eight bladder cancer (BC) biomarkers (EGFR, RRM1, PD-L1, BRCA1, TUBB3, ERCC, ERCC1, aberrantly glycosylated integrin α3β1 (AG) and CK5/6) were developed. BC samples from patients who showed a pathologic response (n = 39) and non-response (n = 13) were applied to the panel analysis. ERBB2, FGFR3 and PIK3CA exclusively altered in the responders group (19/39, 48.7%), in which FGFR3 mutations were significantly enriched in patients with a response in the cohort (14/39, 35.9%; P = 0.01). Additionally, strong expression of ERCC1 was associated with a pathologic response (P = 0.01). However, positive lymph node metastasis (P < 0.01) and lymph-vascular invasion (LVI) (P = 0.03) were correlated with a non-response. Overall, the data show that FGFR3 mutations and elevated expression of ERCC1 in MIBCs are potential predictive biomarkers of the response to NAC.

Feng LR, Fernández-Martínez JL, Zaal KJM, et al.
mGluR5 mediates post-radiotherapy fatigue development in cancer patients.
Transl Psychiatry. 2018; 8(1):110 [PubMed] Article available free on PMC after 01/11/2019 Related Publications
Cancer-related fatigue (CRF) is a common burden in cancer patients and little is known about its underlying mechanism. The primary aim of this study was to identify gene signatures predictive of post-radiotherapy fatigue in prostate cancer patients. We employed Fisher Linear Discriminant Analysis (LDA) to identify predictive genes using whole genome microarray data from 36 men with prostate cancer. Ingenuity Pathway Analysis was used to determine functional networks of the predictive genes. Functional validation was performed using a T lymphocyte cell line, Jurkat E6.1. Cells were pretreated with metabotropic glutamate receptor 5 (mGluR5) agonist (DHPG), antagonist (MPEP), or control (PBS) for 20 min before irradiation at 8 Gy in a Mark-1 γ-irradiator. NF-κB activation was assessed using a NF-κB/Jurkat/GFP Transcriptional Reporter Cell Line. LDA achieved 83.3% accuracy in predicting post-radiotherapy fatigue. "Glutamate receptor signaling" was the most significant (p = 0.0002) pathway among the predictive genes. Functional validation using Jurkat cells revealed clustering of mGluR5 receptors as well as increased regulated on activation, normal T cell expressed and secreted (RANTES) production post irradiation in cells pretreated with DHPG, whereas inhibition of mGluR5 activity with MPEP decreased RANTES concentration after irradiation. DHPG pretreatment amplified irradiation-induced NF-κB activation suggesting a role of mGluR5 in modulating T cell activation after irradiation. These results suggest that mGluR5 signaling in T cells may play a key role in the development of chronic inflammation resulting in fatigue and contribute to individual differences in immune responses to radiation. Moreover, modulating mGluR5 provides a novel therapeutic option to treat CRF.

Whitney J, Corredor G, Janowczyk A, et al.
Quantitative nuclear histomorphometry predicts oncotype DX risk categories for early stage ER+ breast cancer.
BMC Cancer. 2018; 18(1):610 [PubMed] Article available free on PMC after 01/11/2019 Related Publications
BACKGROUND: Gene-expression companion diagnostic tests, such as the Oncotype DX test, assess the risk of early stage Estrogen receptor (ER) positive (+) breast cancers, and guide clinicians in the decision of whether or not to use chemotherapy. However, these tests are typically expensive, time consuming, and tissue-destructive.
METHODS: In this paper, we evaluate the ability of computer-extracted nuclear morphology features from routine hematoxylin and eosin (H&E) stained images of 178 early stage ER+ breast cancer patients to predict corresponding risk categories derived using the Oncotype DX test. A total of 216 features corresponding to the nuclear shape and architecture categories from each of the pathologic images were extracted and four feature selection schemes: Ranksum, Principal Component Analysis with Variable Importance on Projection (PCA-VIP), Maximum-Relevance, Minimum Redundancy Mutual Information Difference (MRMR MID), and Maximum-Relevance, Minimum Redundancy - Mutual Information Quotient (MRMR MIQ), were employed to identify the most discriminating features. These features were employed to train 4 machine learning classifiers: Random Forest, Neural Network, Support Vector Machine, and Linear Discriminant Analysis, via 3-fold cross validation.
RESULTS: The four sets of risk categories, and the top Area Under the receiver operating characteristic Curve (AUC) machine classifier performances were: 1) Low ODx and Low mBR grade vs. High ODx and High mBR grade (Low-Low vs. High-High) (AUC = 0.83), 2) Low ODx vs. High ODx (AUC = 0.72), 3) Low ODx vs. Intermediate and High ODx (AUC = 0.58), and 4) Low and Intermediate ODx vs. High ODx (AUC = 0.65). Trained models were tested independent validation set of 53 cases which comprised of Low and High ODx risk, and demonstrated per-patient accuracies ranging from 75 to 86%.
CONCLUSION: Our results suggest that computerized image analysis of digitized H&E pathology images of early stage ER+ breast cancer might be able predict the corresponding Oncotype DX risk categories.

Ma Y, Zhang H, Xiong C, et al.
CD146 mediates an E-cadherin-to-N-cadherin switch during TGF-β signaling-induced epithelial-mesenchymal transition.
Cancer Lett. 2018; 430:201-214 [PubMed] Related Publications
Cadherin switch is an initiating factor of epithelial-mesenchymal transition (EMT) and is intimately correlated with cancer metastatic potential; however, its underlying mechanisms remain unclear. Here, using a transforming growth factor-β (TGF-β)-induced EMT model, we provide explicit evidence that CD146, with elevated expression and activity in a variety of cancers, is a key factor involved in the cadherin switch. We show that CD146 can be induced by TGF-β signaling. Moreover, CD146 expression is positively correlated with the activation levels of STAT3/Twist and ERK pathways. Transcriptional response of the CD146/STAT3/Twist cascade inhibits E-cadherin expression, whereas the CD146/ERK cascade enhances N-cadherin expression. CD146 overexpression also significantly promotes EMT in both mouse embryonic fibroblasts (MEFs) and ovarian cancer cells. Clinically, ovarian cancer patients with detectable CD146 expression had a significantly lower survival rate than that of patients without CD146 expression. Furthermore, CD146-deficient MEFs exhibited decreased motility as a result of reversion in this cadherin switch, strongly suggesting that targeting CD146 is a potential strategy for cancer treatment. Therefore, CD146-mediated regulation of the E-cadherin-to-N-cadherin switch provides an insight into the general mechanisms of EMT as well as cancer metastasis.

Lei Y, Wang K, Wu SY, et al.
2'-Fluoro ribonucleic acid modified DNA dual-probe sensing strategy for enzyme-amplified electrochemical detection of double-strand DNA of PML/RARα related fusion gene.
Biosens Bioelectron. 2018; 112:170-176 [PubMed] Related Publications
In the study, a novel sensing strategy based on dual-probe mode, which involved two groups of 2'-fluoro ribonucleic acid (2'-F RNA) modified probes, was designed for the detection of synthetic target double-strand DNA (dsDNA) of PML/RARα fusion genes in APL. And each pair of probes contained a thiolated capture probe (C1 or C2) immobilized on one of electrode surfaces in the dual-channel electrochemical biosensor and a biotinylated reporter probe (R1 or R2). The two groups of 2'-F RNA modified probes were separately complementary with the corresponding strand (Sa or Sb) from target dsDNA in order to prevent renaturation of target dsDNA. Through flanking target dsDNA, two "sandwitch" complexes (C1/Sa/R1 and C2/Sb/R2) were separately shaped by capture probes (C1 and C2) and free reporter probes (R1 and R2) in hybridization solution on the surfaces of different electrodes after the thermal denaturation. The biotin-modified enzyme which produced the measurable electrochemical current signal was localized to the surface by affinity binding between biotin with streptavidin. Under the optimal condition, the biosensor was able to detect 84 fM target dsDNA and showed a good specificity in PBS hybridization solution. Otherwise, the investigations of the specificity and sensitivity of the biosensor were carried out further in the mixed hybridization solution containing different kinds of mismatch sequences as interference background. It can be seen that under a certain interference background, the method still exhibited excellent selectivity and specificity for the discrimination between the fully-complementary and the mismatch sequences. The results of our research laid a good basis of further detection research in practical samples.

Wang X, Zhang J, Wu H, et al.
PET imaging of Hsp90 expression in pancreatic cancer using a new
Amino Acids. 2018; 50(7):897-907 [PubMed] Related Publications
Heat shock protein 90 (Hsp90) plays a vital role in the progress of malignant disease and elevated Hsp90 expression has been reported in pancreatic cancer. In this study, we radiolabeled a dimeric Sansalvamide A derivative (Di-San A1) with

Singh G, Sankanagoudar S, Dogra P, Chandra NC
Interlink between cholesterol & cell cycle in prostate carcinoma.
Indian J Med Res. 2017; 146(Suppl):S38-S44 [PubMed] Article available free on PMC after 01/11/2019 Related Publications
Background & objectives: Earlier reports have shown hypocholesterolaemia in cancer patients and high number of lipid rafts in cancer cells. The primary objective of this study was to compare the intracellular cholesterol turnover in non-cancerous (benign) prostatic hyperplasia (BPH) and carcinoma prostate (CAP) with normal prostate cells obtained from patients undergoing radical cystectomy for carcinoma bladder (sham control).
Methods: ELISA-based estimation of prostate-specific antigen (PSA), evaluation of expression of low-density lipoprotein receptor (LDLR), peripheral-type benzodiazepine receptor (PBR) and cyclin E, immunohistochemistry and confocal microscopy, measurement of integrated optical density of the diaminobenzidine (DAB)-stained immunohistograms, isolation of nucleus and cell cytoplasm from prostate tissue by ultracentrifugation followed by estimation of cholesterol spectrophotometrically in isolated nuclear and cytoplasmic fractions were performed.
Results: Seventy five individuals, 25 for each group (BPH n=25; CAP n=25 and sham control n=25), were included in the study. Cholesterol was increased in the cytoplasm and nucleus of the prostate cancer cells along with elevated expression of LDLR. Increased cholesterol concentration in the cell nucleus was found comparable with the increased expression of cholesterol transporter viz. PBR in the prostate tumour tissues as compared to its expression in normal prostate cells obtained from individuals undergoing radical cystectomy for carcinoma bladder. Cell cycle protein cyclin E was also highly expressed in cancer tissues.
Interpretation & conclusions: The present findings along with increased expression of cell cycle protein cyclin E in the cell nucleus of the tumour tissue suggested the possibility of an intriguing role of cholesterol in the mechanism of cell cycle process of prostate cell proliferation.

Pěnčíková K, Svržková L, Strapáčová S, et al.
In vitro profiling of toxic effects of prominent environmental lower-chlorinated PCB congeners linked with endocrine disruption and tumor promotion.
Environ Pollut. 2018; 237:473-486 [PubMed] Article available free on PMC after 01/11/2019 Related Publications
The mechanisms contributing to toxic effects of airborne lower-chlorinated PCB congeners (LC-PCBs) remain poorly characterized. We evaluated in vitro toxicities of environmental LC-PCBs found in both indoor and outdoor air (PCB 4, 8, 11, 18, 28 and 31), and selected hydroxylated metabolites of PCB 8, 11 and 18, using reporter gene assays, as well as other functional cellular bioassays. We focused on processes linked with endocrine disruption, tumor promotion and/or regulation of transcription factors controlling metabolism of both endogenous compounds and xenobiotics. The tested LC-PCBs were found to be mostly efficient anti-androgenic (within nanomolar - micromolar range) and estrogenic (at micromolar concentrations) compounds, as well as inhibitors of gap junctional intercellular communication (GJIC) at micromolar concentrations. PCB 8, 28 and 31 were found to partially inhibit the aryl hydrocarbon receptor (AhR)-mediated activity. The tested LC-PCBs were also partial constitutive androstane receptor (CAR) and pregnane X receptor (PXR) agonists, with PCB 4, 8 and 18 being the most active compounds. They were inactive towards other nuclear receptors, such as vitamin D receptor, thyroid receptor α, glucocorticoid receptor or peroxisome proliferator-activated receptor γ. We found that only PCB 8 contributed to generation of oxidative stress, while all tested LC-PCBs induced arachidonic acid release (albeit without further modulations of arachidonic acid metabolism) in human lung epithelial cells. Importantly, estrogenic effects of hydroxylated (OH-PCB) metabolites of LC-PCBs (4-OH-PCB 8, 4-OH-PCB 11 and 4'-OH-PCB 18) were higher than those of the parent PCBs, while their other toxic effects were only slightly altered or suppressed. This suggested that metabolism may alter toxicity profiles of LC-PCBs in a receptor-specific manner. In summary, anti-androgenic and estrogenic activities, acute inhibition of GJIC and suppression of the AhR-mediated activity were found to be the most relevant modes of action of airborne LC-PCBs, although they partially affected also additional cellular targets.

Jia X, Cheng J, Shen Z, et al.
Zoledronic acid sensitizes breast cancer cells to fulvestrant via ERK/HIF-1 pathway inhibition in vivo.
Mol Med Rep. 2018; 17(4):5470-5476 [PubMed] Related Publications
Previous studies have reported that hypoxia-inducible factor (HIF)-1α confers endocrine resistance and that zoledronic acid (ZOL) decreases HIF‑1α expression in estrogen receptor‑positive breast cancer. The present study investigated the effect of the combination treatment with ZOL and fulvestrant and its possible mechanism for HIF‑1α inhibition in vitro and in vivo. First, cell proliferation, clonogenic ability and HIF‑1α expression by western blotting were determined in MCF‑7 breast cancer cells stably expressing HIF‑1α in vitro. Next, a mouse xenograft model was established with the HIF‑1α‑overexpressing MCF‑7 breast cancer cells, and treated with PBS, fulvestrant, ZOL or fulvestrant plus ZOL. Tumor volumes were compared and animal [18F]‑fluoromisonidazole (FMISO) positron emission tomography‑computer tomography (PET‑CT) was used to detect the hypoxic status of the xenograft tumors. Protein expression levels of HIF‑1α in the xenograft tumors were detected by immunohistochemistry and western blotting. The results demonstrated that the HIF-1α-overexpressing xenograft tumors grew faster and larger compared with control tumors. The animal [18F]‑FMISO PET‑CT also confirmed these results. [18F]‑FMISO uptake was significantly higher in HIF‑1α‑overexpressing xenograft tumors compared with control tumors. In addition, the combination treatment with ZOL and fulvestrant acted synergistically in the mouse xenograft model in vivo to significantly reduce tumor burden. Similarly, combination of ZOL and fulvestrant significantly reduced tumor cell growth in vitro. ZOL alone did not inhibit the tumor growth of MCF‑7 cells stably expressing HIF‑1α. Furthermore, ZOL significantly inhibited extracellular signal‑regulated kinase (ERK) 1/2 phosphorylation, while phosphoinositide 3‑kinase/AKT signaling was not affected. In conclusion, the present study demonstrated that ZOL significantly increased the sensitivity of breast cancer cells to fulvestrant through inhibition of the ERK/HIF-1α pathway.

Wang H, Wang J, Shi X, Ding Y
Genetically engineered bone marrow-derived mesenchymal stem cells co-expressing IFN-γ and IL-10 inhibit hepatocellular carcinoma by modulating MAPK pathway.
J BUON. 2017 Nov-Dec; 22(6):1517-1524 [PubMed] Related Publications
PURPOSE: One of the major challenges in delivering cytokines for the treatment of hepatocellular carcinoma (HCC) is the mode of delivery. This study hypothesized that genetically engineered bone marrow derived mesenchymal stem cells (BMSCs) co-expressing IFN-γ and IL-10 can serve as a potential therapeutic strategy in the treatment of HCC by inhibiting cell proliferation.
METHODS: Male Sprague-Dawley rats (n=5, 200-250 g) for BMSCs isolation and Nude/SCID mice (n=35,12-20g) to develop liver cancer xenograft model were used. Mice were subcutaneously injected HepG2 cell suspension on left flank. BMSCs were genetically engineered with the recombinant lentiviral vectors expressing IFN-γ and IL-10. The experiments were performed in 5 groups (phosphate buffered saline/PBS, BMSCs, BMSC-IFN-γ, BMSC-IL-10 and BMSC-IFN-γ-IL-10) and the genetically engineered BMSCs were transplanted into HCC mice. Cell viability was measured by MTT assay followed by the evaluation of the effect of cell-cycle regulators (p21, p27, cyclin D1 and Rb). Protein expression of p38, ERK and JNK was assessed by immunohistochemistry using the cell proliferation marker Ki67.
RESULTS: The combination of two cytokines (IFN-γ and IL- 10) engineered into BMSCs resulted in a significant reduction in HepG2 cell viability (*p<0.05 vs PBS-treated and #p<0.05 vs BMSC-treated group). Significantly increased expression of cell cycle inhibitors p21 and p27 in parallel with reduced cyclin D1 expression were observed. Reduced phosphorylation of Rb demonstrated the repression of G1/S progression. BMSC-IFN-γ-IL-10 treatment significantly reduced the tumor growth at the end of 36 days compared to the group treated with PBS or BMSCs alone. This effect was accompanied with the modulation of MAPK pathway with the activation of p38 and JNK, and inactivation of ERK.
CONCLUSION: The co-expression of IFN-γ and IL-10 in BMSCs inhibits HCC in vitro and in vivo by modulating cell cycle regulators and MAPK pathway.

He Y, Lu J, Ye Z, et al.
Androgen receptor splice variants bind to constitutively open chromatin and promote abiraterone-resistant growth of prostate cancer.
Nucleic Acids Res. 2018; 46(4):1895-1911 [PubMed] Article available free on PMC after 01/11/2019 Related Publications
Androgen receptor (AR) splice variants (ARVs) are implicated in development of castration-resistant prostate cancer (CRPC). Upregulation of ARVs often correlates with persistent AR activity after androgen deprivation therapy (ADT). However, the genomic and epigenomic characteristics of ARV-dependent cistrome and the disease relevance of ARV-mediated transcriptome remain elusive. Through integrated chromatin immunoprecipitation coupled sequencing (ChIP-seq) and RNA sequencing (RNA-seq) analysis, we identified ARV-preferential-binding sites (ARV-PBS) and a set of genes preferentially transactivated by ARVs in CRPC cells. ARVs preferentially bind to enhancers located in nucleosome-depleted regions harboring the full AR-response element (AREfull), while full-length AR (ARFL)-PBS are enhancers resided in closed chromatin regions containing the composite FOXA1-nnnn-AREhalf motif. ARV-PBS exclusively overlapped with AR binding sites in castration-resistant (CR) tumors in patients and ARV-preferentially activated genes were up-regulated in abiraterone-resistant patient specimens. Expression of ARV-PBS target genes, such as oncogene RAP2A and cell cycle gene E2F7, were significantly associated with castration resistance, poor survival and tumor progression. We uncover distinct genomic and epigenomic features of ARV-PBS, highlighting that ARVs are useful tools to depict AR-regulated oncogenic genome and epigenome landscapes in prostate cancer. Our data also suggest that the ARV-preferentially activated transcriptional program could be targeted for effective treatment of CRPC.

Kuss BJ, Tam CS
Management of high risk chronic lymphocytic leukaemia (CLL) patients in Australia.
Intern Med J. 2017; 47 Suppl 6:5-10 [PubMed] Related Publications
BACKGROUND: Chronic lymphocytic leukaemia (CLL) frequently responds to chemoimmunotherapy combining cytotoxic chemotherapy and monoclonal antibodies. However, CLL is associated with significant genetic heterogeneity, and some high-risk forms are known to be chemo-resistant and associated with early relapse.
AIMS: To review the current treatment paradigm of patients with high-risk disease, in particular those with del(17p) and TP53 variants.
RESULTS: A 'watch and wait' approach is recommended for all patients who are asymptomatic. When symptomatic, fluorescence in situ hybridisation testing should be performed and gene sequencing considered subsequently to identify del(17p) and TP53 variants respectively. In the front-line setting, treatment within a clinical trial is the preferred option. In the relapsed or refractory setting, patients with del(17p) or TP53 aberrations should be offered treatment with a novel agent, such as ibrutinib, idelalisib-rituximab or venetoclax. However, of note, at the date of this publication venetoclax is not PBS reimbursed, and ibrutinib will not be reimbursed until 1 December 2017.
CONCLUSION: Testing for del(17p) and TP53 variants identifies high-risk CLL that requires specialist management.

Javadekar SM, Yadav R, Raghavan SC
DNA structural basis for fragility at peak III of BCL2 major breakpoint region associated with t(14;18) translocation.
Biochim Biophys Acta Gen Subj. 2018; 1862(3):649-659 [PubMed] Related Publications
Maintaining genome integrity is crucial for normal cellular functions. DNA double-strand breaks (DSBs), when unrepaired, can potentiate chromosomal translocations. t(14;18) translocation involving BCL2 gene on chromosome 18 and IgH loci at chromosome 14, could lead to follicular lymphoma. Molecular basis for fragility of translocation breakpoint regions is an active area of investigation. Previously, formation of non-B DNA structures like G-quadruplex, triplex, B/A transition were investigated at peak I of BCL2 major breakpoint region (MBR); however, it is less understood at peak III. In vitro gel shift assays show faster mobility for MBR peak III sequences, unlike controls. CD studies of peak III sequences reveal a spectral pattern different from B-DNA. Although complementary C-rich stretches exhibit single-strandedness, corresponding guanine-rich sequences do not show DMS protection, ruling out G-quadruplex and triplex DNA. Extrachromosomal assay indicates that peak III halts transcription, unlike its mutated version. Taken together, multiple lines of evidence suggest formation of potential cruciform DNA structure at MBR peak III, which was also supported by in silico studies. Thus, our study reveals formation of non-B DNA structure which could be a basis for fragility at BCL2 breakpoint regions, eventually leading to chromosomal translocations.

Guo S, Fan J, Wang B, et al.
Highly Selective Red-Emitting Fluorescent Probe for Imaging Cancer Cells in Situ by Targeting Pim-1 Kinase.
ACS Appl Mater Interfaces. 2018; 10(2):1499-1507 [PubMed] Related Publications
Based on the fact that enzyme-targeting probes are highly sensitive and selective, a novel red-emitting probe (NB-BF) for Pim-1 kinase including three parts, fluorophore (NB), linker, and inhibitor (BF), has been designed for cancer optical imaging. In its free state, NB-BF is folded and the fluorescence quenched by PET between fluorophore and inhibitor both in PBS buffer and in normal cells. Significantly, it emitted strong red fluorescence in Pim-1 overexpressed cancer cells. The specificity of NB-BF for Pim-1 kinase was directly demonstrated by gene silencing analysis. Furthermore, it is the first time to know where Pim-1 kinase mainly distributes at mitochondria with Pearson's correlation factor (R

Harris C, Daniels B, Ward RL, Pearson SA
Retrospective comparison of Australia's Pharmaceutical Benefits Scheme claims data with prescription data in HER2-positive early breast cancer patients, 2008-2012.
Public Health Res Pract. 2017; 27(5) [PubMed] Related Publications
OBJECTIVES: Dispensing claims are used increasingly to investigate the real-world use and impact of prescribed medicines. Claims databases, established for payment purposes, lack clinical data and only capture prescriptions for which insurers pay a contribution. We compare Australia's Pharmaceutical Benefits Scheme (PBS) dispensing claims of HER2-positive early breast cancer patients with medicines prescribed and administered to determine the accuracy of dispensing data to identify treatment protocols, number of treatment cycles and durations of therapy.
METHOD: Our cohort comprised 110 female HER2-positive early breast cancer patients who started treatment at four cancer centres in New South Wales, Australia, between 2008 and 2011. Patients consented to retrospective medical chart audit and linkage to PBS claims data. We constructed protocols from prescribing and dispensing records independently, based on the timing of trastuzumab and cytotoxic treatments; and estimated the median number of treatment cycles and duration of therapy by protocol.
RESULTS: Patients' median age was 53 years (range 21-86). Two chemotherapy protocols accounted for 90% of chemotherapy protocols: doxorubicin and cyclophosphamide followed by a paclitaxel or docetaxel and trastuzumab (known as ACTH; 58.2%) and trastuzumab with docetaxel, carboplatin and trastuzumab (known as TCH; 31.2%). Seventy-six patients (69.1%) were assigned the same protocols based on prescribing and claims data. Twenty-six of the protocols that did not match were due to the absence of cyclophosphamide in PBS data because it falls below the patient copayment for general PBS beneficiaries. Compared with prescription data, the number of treatment cycles was underestimated in dispensing data (30 vs 44 for ACTH and 26.5 vs 29 for TCH); however, median durations of therapy were well matched (422 vs 442 days for ACTH and 368 vs 367 for TCH).
CONCLUSIONS: PBS dispensing data provide an alternative option to prescription data for estimating cancer medicine use. Recent changes to PBS data capture that include all medicines costing less than the copayment will strengthen the capacity of PBS data to reflect prescribing practice in all patients, including treatment protocols and duration of therapy in patients with complete ascertainment of PBS dispensing history.

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