This gene encodes a member of the Abelson family of nonreceptor tyrosine protein kinases. The protein is highly similar to the c-abl oncogene 1 protein, including the tyrosine kinase, SH2 and SH3 domains, and it plays a role in cytoskeletal rearrangements through its C-terminal F-actin- and microtubule-binding sequences. This gene is expressed in both normal and tumor cells, and is involved in translocation with the ets variant 6 gene in leukemia. Multiple alternatively spliced transcript variants encoding different protein isoforms have been found for this gene. [provided by RefSeq, Nov 2009]
t(1;12)(q25;p13) in Leukaemia (AML & ALL) The ETV6 (TEL) gene is frequently rearranged to various translocation partners in human leukemias. In a small number of cases the ETV6 gene is translocated with the ABL2 gene. In a RT-PCR study of samples from 176 patients with acute lymphoblastic leukemia (Zhou et al, 2012) found 15 had ETV6 gene rearrangements and of these 2 were ETV6/ABL1 translocations.
AIM: To establish a permanent METHODS: CRISPR-Cas9 system used was purchased from Dharmacon GE Life Sciences (Lafayette, CO, United States) and permanent knockout was performed according to manufacturer's recommendations. Wound-healing assay was performed to investigate the effect of
Xie W, Stopsack KH, Drouin SJ, et al. Association of genetic variation of the six gene prognostic model for castration-resistant prostate cancer with survival. Prostate. 2019; 79(1):73-80 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
BACKGROUND: We previously identified a blood RNA transcript-based model consisting of six immune or inflammatory response genes (ABL2, SEMA4D, ITGAL, C1QA, TIMP1, and CDKN1A) that was prognostic for survival in cohorts of men with castration-resistant prostate cancer (CRPC). We investigated whether inherited variation in these six genes was associated with overall survival (OS) in men with CRPC. METHODS: The test cohort comprised 600 patients diagnosed with CRPC between 1996 and 2011 at Dana-Farber Cancer Institute. Genotyping of 66 tagging single nucleotide polymorphisms (SNPs) spanning the six genes was performed on blood derived DNAs. For the top four SNPs (P < 0.05), validation was conducted in an independent cohort of 223 men diagnosed with CRPC between 2000 and 2014. Multivariable Cox regression adjusting for known prognostic factors estimated hazard ratios (HR) and 95% confidence intervals (CI) of the association of genetic variants with OS. RESULTS: Two thirds of patients in both cohorts had metastases at CRPC diagnosis. Median OS from CRPC diagnosis was 3.6 (95%CI 3.3-4.0) years in the test cohort and 4.6 (95%CI 3.8-5.2) years in the validation cohort. Fifty-nine SNPs in Hardy-Weinberg equilibrium were analyzed. The major alleles of rs1318056 and rs1490311 in ABL2, and the minor alleles of rs2073917 and rs3764322 in ITGAL were associated with increased risk of death in the test cohort (adjusted-HRs 1.27-1.39; adjusted-p <0.05; false discovery rate <0.35). In the validation cohort, a similar association with OS was observed for rs1318056 in ABL2 (adjusted-HR 1.44; 95%CI 0.89-2.34) and rs2073917 in ITGAL (adjusted-HR 1.41; 95%CI 0.82-2.42). The associations did not reach statistical significance most likely due to the small sample size of the validation cohort (adjusted-p = 0.142 and 0.209, respectively). Additional eQTL analysis indicated that minor alleles of rs1318056 and rs1490311 in ABL2 are associated with a lower ABL2 expression in blood. CONCLUSIONS: These findings corroborate our initial work on the RNA expression of genes involved in immunity and inflammation from blood and clinical outcome and suggest that germline polymorphisms in ABL2 and ITGAL may be associated with the risk of death in men with CRPC. Further studies are needed to validate these findings and to explore their functional mechanisms.
Choi JR, Koh SB, Kim HR, et al. Radon Exposure-induced Genetic Variations in Lung Cancers among Never Smokers. J Korean Med Sci. 2018; 33(29):e207 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
Background: Lung cancer in never smokers (LCINS) differs etiologically and clinically from lung cancer attributed to smoking. After smoking, radon exposure is the second leading cause and the primary risk factor of lung cancer among never smokers. Exposure to radon can lead to genetic and epigenetic alterations in tumor genomes affecting genes and pathways involved in lung cancer development. The present study sought to explore genetic alterations associated with LCINS exposed to radon gas indoors. Methods: Genetic associations were assessed via a case-control study of LCINS (39 cases and 30 controls) using next generation sequencing. Associations between genetic mutations and high exposure to radon were investigated by OncoPrint and heatmap graphs. Bioinformatic analysis was conducted using various tools. According radon exposure levels, we divided subjects in two groups of cases and controls. Results: We found that ABL2 rs117218074, SMARCA4 rs2288845, PIK3R2 rs142933317, MAPK1 rs1803545, and androgen receptor (AR) rs66766400 were associated with LCINS exposed to high radon levels. Among these, Chromodomain helicase DNA-binding protein 4 (CHD4) rs74790047, TSC2 rs2121870, and AR rs66766408 were identified as common exonic mutations in both lung cancer patients and normal individuals exposed to high levels of radon indoor. Conclusion: We identified that CHD4 rs74790047, TSC2 rs2121870, and AR rs66766408 are found to be common exonic mutations in both lung cancer patients and normal individuals exposed to radon indoors. Further analysis is needed to determine whether these genes are completely responsible for LCINS exposed to residential radon.
Pekmezci M, Villanueva-Meyer JE, Goode B, et al. The genetic landscape of ganglioglioma. Acta Neuropathol Commun. 2018; 6(1):47 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
Ganglioglioma is the most common epilepsy-associated neoplasm that accounts for approximately 2% of all primary brain tumors. While a subset of gangliogliomas are known to harbor the activating p.V600E mutation in the BRAF oncogene, the genetic alterations responsible for the remainder are largely unknown, as is the spectrum of any additional cooperating gene mutations or copy number alterations. We performed targeted next-generation sequencing that provides comprehensive assessment of mutations, gene fusions, and copy number alterations on a cohort of 40 gangliogliomas. Thirty-six harbored mutations predicted to activate the MAP kinase signaling pathway, including 18 with BRAF p.V600E mutation, 5 with variant BRAF mutation (including 4 cases with novel in-frame insertions at p.R506 in the β3-αC loop of the kinase domain), 4 with BRAF fusion, 2 with KRAS mutation, 1 with RAF1 fusion, 1 with biallelic NF1 mutation, and 5 with FGFR1/2 alterations. Three gangliogliomas with BRAF p.V600E mutation had concurrent CDKN2A homozygous deletion and one additionally harbored a subclonal mutation in PTEN. Otherwise, no additional pathogenic mutations, fusions, amplifications, or deletions were identified in any of the other tumors. Amongst the 4 gangliogliomas without canonical MAP kinase pathway alterations identified, one epilepsy-associated tumor in the temporal lobe of a young child was found to harbor a novel ABL2-GAB2 gene fusion. The underlying genetic alterations did not show significant association with patient age or disease progression/recurrence in this cohort. Together, this study highlights that ganglioglioma is characterized by genetic alterations that activate the MAP kinase pathway, with only a small subset of cases that harbor additional pathogenic alterations such as CDKN2A deletion.
Liu Y, Shao C, Zhu L, et al. High Expression of ABL2 Suppresses Apoptosis in Gastric Cancer. Dig Dis Sci. 2018; 63(9):2294-2300 [PubMed] Related Publications
BACKGROUND: Diseases associated with Abelson-related gene (also called ABL2) include leukemia; furthermore, previous researches have studied the expressions and functions of ABL2 in different types of malignancies and found that it plays an important role in almost all kinds of cancers. AIMS: Nevertheless, the mechanism of ABL2 in gastric cancer (GC) remains vague. METHODS: In the present study, the level of ABL2 in human GC tissues was detected by immunohistochemistry. Also, the GC cell lines MGC-803 and BGC-823 were selected to stably knock down and overexpress the level of ABL2 by corresponding lentiviral vectors. Puromycin was used to maintain the stable low expression of ABL2 MGC-803 cells compared with control cells; what is more, the high expression of ABL2 BGC-823 cells was also obtained. Based on it, we detected the proteins associated with apoptosis, such as Bcl-2 family and caspase family by western blotting. RESULTS: The most appropriate concentration of puromycin to kill GC cells is 1 µg/mL; then, we obtained the corresponding stable cell lines. Furthermore, we found that high level of ABL2 in BGC-823 cells increased the expression of Bcl-XL, total PARP, and caspase3, while decreased the level of cleaved caspase3 and cleaved caspase9. Consistent results are received in MGC-803 cells. In addition, ABL2 overexpression led to the protein related with Ras/Erk and PI3K/AKT signaling pathway increased; also, we found that the major proteins play a significant role in it. CONCLUSION: All the data showed that high expression of ABL2 suppresses apoptosis through Ras/Erk and PI3K/AKT signaling pathway in GC cell lines.
Tran TH, Harris MH, Nguyen JV, et al. Prognostic impact of kinase-activating fusions and IKZF1 deletions in pediatric high-risk B-lineage acute lymphoblastic leukemia. Blood Adv. 2018; 2(5):529-533 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
Recurrent chromosomal rearrangements carry prognostic significance in pediatric B-lineage acute lymphoblastic leukemia (B-ALL). Recent genome-wide analyses identified a high-risk B-ALL subtype characterized by a diverse spectrum of genetic alterations activating kinases and cytokine receptor genes. This subtype is associated with a poor prognosis when treated with conventional chemotherapy but has demonstrated sensitivity to the relevant tyrosine kinase inhibitors. We sought to determine the frequency of kinase-activating fusions among National Cancer Institute (NCI) high-risk, Ph-negative, B-ALL patients enrolled on Dana-Farber Cancer Institute ALL Consortium Protocol 05-001 and to describe their associated clinical characteristics and outcomes. Among the 105 patients screened, 16 (15%) harbored an ABL-class fusion (
Fang C, Dai CY, Mei Z, et al. microRNA-193a stimulates pancreatic cancer cell repopulation and metastasis through modulating TGF-β2/TGF-βRIII signalings. J Exp Clin Cancer Res. 2018; 37(1):25 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
BACKGROUND: Pancreatic cancer characterizes high recurrence and poor prognosis. In clinical practice, radiotherapy is widely used for pancreatic cancer treatment. However, the outcome remains undesirable due to tumor repopulation and following recurrence and metastasis after radiation. So, it is highly needed to explore the underlying molecular mechanisms and accordingly develop therapeutic strategies. Our previous studies revealed that dying cells from chemoradiation could stimulate repopulation of surviving pancreatic cancer cells. However, we still knew little how dying cells provoke pancreatic cancer cell repopulation. We herein would explore the significance of TGF-β2 changes and investigate the modulation of microRNA-193a (miR-193a), and identify their contributions to pancreatic cancer repopulation and metastasis. METHODS: In vitro and in vivo repopulation models were established to mimic the biological processes of pancreatic cancer after radiation. Western blot, real-time PCR and dual-luciferase reporter assays were accordingly used to detect miR-193a and TGF-β2/TGF-βRIII signalings at the level of molecular, cellular and experimental animal model, respectively. Flow cytometry analysis, wound healing and transwell assay, vascular endothelial cell penetration experiment, and bioluminescence imaging were employed to assessthe biological behaviors of pancreatic cancer after different treatments. Patient-derived tumor xenograft (PDX) mice models were established to evaluate the therapeutic potential of miR-193a antagonist on pancreatic cancer repopulation and metastasis after radiation. RESULTS: miR-193a was highly expressed in the irradiated pancreatic cancer dying cells, accordingly elevated the level of miR-193a in surviving cells, and further promoted pancreatic cancer repopulation and metastasis in vitro and in vivo. miR-193a accelerated pancreatic cancer cell cycle and stimulated cell proliferation and repopulation through inhibiting TGF-β2/TGF-βRIII/SMADs/E2F6/c-Myc signaling, and even destroyed normal intercellular junctions and promoted metastasis via repressing TGF-β2/TGF-βRIII/ARHGEF15/ABL2 pathway. Knockdown of miR-193a or restoration of TGF-β2/TGF-βRIII signaling in pancreatic cancer cells was found to block pancreatic cancer repopulation and metastasis after radiation. In PDX models, the treatment in combination with miR-193a antagonist and radiation was found to dramatically inhibit pancreatic cancer cell repopulation and metastasis, and further improved the survival after radiation. CONCLUSIONS: Our findings demonstrated that miR-193a stimulated pancreatic cancer cell repopulation and metastasis through modulating TGF-β2/TGF-βRIII signalings, and miR-193a might be a potential therapeutic target for pancreatic cancer repopulation and metastasis.
Boer JM, den Boer ML BCR-ABL1-like acute lymphoblastic leukaemia: From bench to bedside. Eur J Cancer. 2017; 82:203-218 [PubMed] Related Publications
Acute lymphoblastic leukaemia (ALL) occurs in approximately 1:1500 children and is less frequently found in adults. The most common immunophenotype of ALL is the B cell lineage and within B cell precursor ALL, specific genetic aberrations define subtypes with distinct biological and clinical characteristics. With more advanced genetic analysis methods such as whole genome and transcriptome sequencing, novel genetic subtypes have recently been discovered. One novel class of genetic aberrations comprises tyrosine kinase-activating lesions, including translocations and rearrangements of tyrosine kinase and cytokine receptor genes. These newly discovered genetic aberrations are harder to detect by standard diagnostic methods such as karyotyping, fluorescent in situ hybridisation (FISH) or polymerase chain reaction (PCR) because they are diverse and often cryptic. These lesions involve one of several tyrosine kinase genes (among others, v-abl Abelson murine leukaemia viral oncogene homologue 1 (ABL1), v-abl Abelson murine leukaemia viral oncogene homologue 2 (ABL2), platelet-derived growth factor receptor beta polypeptide (PDGFRB)), each of which can be fused to up to 15 partner genes. Together, they compose 2-3% of B cell precursor ALL (BCP-ALL), which is similar in size to the well-known fusion gene BCR-ABL1 subtype. These so-called BCR-ABL1-like fusions are mutually exclusive with the sentinel translocations in BCP-ALL (BCR-ABL1, ETV6-RUNX1, TCF3-PBX1, and KMT2A (MLL) rearrangements) and have the promising prospect to be sensitive to tyrosine kinase inhibitors similar to BCR-ABL1. In this review, we discuss the types of tyrosine kinase-activating lesions discovered, and the preclinical and clinical evidence for the use of tyrosine kinase inhibitors in the treatment of this novel subtype of ALL.
Reshmi SC, Harvey RC, Roberts KG, et al. Targetable kinase gene fusions in high-risk B-ALL: a study from the Children's Oncology Group. Blood. 2017; 129(25):3352-3361 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
Philadelphia chromosome-like (Ph-like) acute lymphoblastic leukemia (ALL) is a high-risk subtype characterized by genomic alterations that activate cytokine receptor and kinase signaling. We examined the frequency and spectrum of targetable genetic lesions in a retrospective cohort of 1389 consecutively diagnosed patients with childhood B-lineage ALL with high-risk clinical features and/or elevated minimal residual disease at the end of remission induction therapy. The Ph-like gene expression profile was identified in 341 of 1389 patients, 57 of whom were excluded from additional analyses because of the presence of
Yokota A, Hirai H, Shoji T, et al. Constitutively active ABL family kinases, TEL/ABL and TEL/ARG, harbor distinct leukemogenic activities in vivo. Leukemia. 2017; 31(12):2742-2751 [PubMed] Related Publications
ABL (ABL1) and ARG (ABL2) are highly homologous to each other in overall domain structure and amino-acid sequence, with the exception of their C termini. As with ABL, translocations that fuse ARG to ETV6/TEL have been identified in patients with leukemia. To assess the in vivo leukemogenic activity of constitutively active ABL and ARG, we generated a bone marrow (BM) transplantation model using the chimeric forms TEL/ABL and TEL/ARG, which have comparable kinase activities. TEL/ABL rapidly induced fatal myeloid leukemia in recipient mice, whereas recipients of TEL/ARG-transduced cells did not develop myeloid leukemia, instead, they succumbed to a long-latency infiltrative mastocytosis that could be adoptively transferred to secondary recipients. Swapping of the C termini of ABL and ARG altered disease latency and phenotypes. In a detailed in vitro study, TEL/ARG strongly promoted mast cell differentiation in response to stem cell factor or interleukin-3, whereas TEL/ABL preferentially induced myeloid differentiation of hematopoietic stem/progenitor cells. These results indicate that ABL and ARG kinase activate distinct differentiation pathways to induce specific diseases in vivo, that is, myeloid leukemia and mastocytosis, respectively. Further elucidation of the differences in their properties should provide important insight into the pathogenic mechanisms of oncogenes of the ABL kinase family.
Boer JM, Steeghs EM, Marchante JR, et al. Tyrosine kinase fusion genes in pediatric BCR-ABL1-like acute lymphoblastic leukemia. Oncotarget. 2017; 8(3):4618-4628 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
Approximately 15% of pediatric B cell precursor acute lymphoblastic leukemia (BCP-ALL) is characterized by gene expression similar to that of BCR-ABL1-positive disease and unfavorable prognosis. This BCR-ABL1-like subtype shows a high frequency of B-cell development gene aberrations and tyrosine kinase-activating lesions. To evaluate the clinical significance of tyrosine kinase gene fusions in children with BCP-ALL, we studied the frequency of recently identified tyrosine kinase fusions, associated genetic features, and prognosis in a representative Dutch/German cohort. We identified 14 tyrosine kinase fusions among 77 BCR-ABL1-like cases (18%) and none among 76 non-BCR-ABL1-like B-other cases. Novel exon fusions were identified for RCSD1-ABL2 and TERF2-JAK2. JAK2 mutation was mutually exclusive with tyrosine kinase fusions and only occurred in cases with high CRLF2 expression. The non/late response rate and levels of minimal residual disease in the fusion-positive BCR-ABL1-like group were higher than in the non-BCR-ABL1-like B-others (p<0.01), and also higher, albeit not statistically significant, compared with the fusion-negative BCR-ABL1-like group. The 8-year cumulative incidence of relapse in the fusion-positive BCR-ABL1-like group (35%) was comparable with that in the fusion-negative BCR-ABL1-like group (35%), and worse than in the non-BCR-ABL1-like B-other group (17%, p=0.07). IKZF1 deletions, predominantly other than the dominant-negative isoform and full deletion, co-occurred with tyrosine kinase fusions. This study shows that tyrosine kinase fusion-positive cases are a high-risk subtype of BCP-ALL, which warrants further studies with specific kinase inhibitors to improve outcome.
Nagy Á, Pongor LS, Szabó A, et al. KRAS driven expression signature has prognostic power superior to mutation status in non-small cell lung cancer. Int J Cancer. 2017; 140(4):930-937 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
KRAS is the most frequently mutated oncogene in non-small cell lung cancer (NSCLC). However, the prognostic role of KRAS mutation status in NSCLC still remains controversial. We hypothesize that the expression changes of genes affected by KRAS mutation status will have the most prominent effect and could be used as a prognostic signature in lung cancer. We divided NSCLC patients with mutation and RNA-seq data into KRAS mutated and wild type groups. Mann-Whitney test was used to identify genes showing altered expression between these cohorts. Mean expression of the top five genes was designated as a "transcriptomic fingerprint" of the mutation. We evaluated the effect of this signature on clinical outcome in 2,437 NSCLC patients using univariate and multivariate Cox regression analysis. Mutation of KRAS was most common in adenocarcinoma. Mutation status and KRAS expression were not correlated to prognosis. The transcriptomic fingerprint of KRAS include FOXRED2, KRAS, TOP1, PEX3 and ABL2. The KRAS signature had a high prognostic power. Similar results were achieved when using the second and third set of strongest genes. Moreover, all cutoff values delivered significant prognostic power (p < 0.01). The KRAS signature also remained significant (p < 0.01) in a multivariate analysis including age, gender, smoking history and tumor stage. We generated a "surrogate signature" of KRAS mutation status in NSCLC patients by computationally linking genotype and gene expression. We show that secondary effects of a mutation can have a higher prognostic relevance than the primary genetic alteration itself.
Yap KL, Furtado LV, Kiyotani K, et al. Diagnostic evaluation of RNA sequencing for the detection of genetic abnormalities associated with Ph-like acute lymphoblastic leukemia (ALL). Leuk Lymphoma. 2017; 58(4):950-958 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
Philadelphia (Ph)-like acute lymphoblastic leukemia (ALL) is a molecular subtype of high-risk B-cell ALL characterized by formation of abnormal gene fusions involving tyrosine kinase (TK) and cytokine receptor genes and activation of TK signaling. Because of the diversity of associated genetic changes, the detection of Ph-like ALL cases currently requires multiple cytogenetic and molecular assays; thus, our goal was to develop a consolidated workflow for detecting genetic abnormalities in Ph-like ALL. We found that total and targeted RNA sequencing (RNAseq)-based approach allowed the detection of abnormal fusion transcripts (EBF1-PDGFRB, P2RY8-CRLF2, RCSD1-ABL1, and RCSD1-ABL2). The bioinformatics algorithm accurately detected the fusion transcripts without prior input about possible events. Additionally, we showed that RNAseq analysis enabled evaluation for disease-associated sequence variants in expressed transcripts. While total RNAseq can be a second tier approach allowing discovery of novel genetic alterations, the targeted RNAseq workflow offers a clinically applicable method for the detection of fusion transcripts.
Cabello P, Pineda B, Tormo E, et al. The Antitumor Effect of Metformin Is Mediated by miR-26a in Breast Cancer. Int J Mol Sci. 2016; 17(8) [PubMed] Article available free on PMC after 01/01/2020 Related Publications
Metformin, a drug approved for diabetes type II treatment, has been associated with a reduction in the incidence of breast cancer and metastasis and increased survival in diabetic breast cancer patients. High levels of miR-26a expression have been proposed as one of the possible mechanisms for this effect; likewise, this miRNA has also been associated with survival/apoptosis processes in breast cancer. Our aim was to evaluate if miR-26a and some of its targets could mediate the effect of metformin in breast cancer. The viability of MDA-MB-231, MDA-MB-468, and MCF-7 breast cancer cell lines was evaluated with an MTT assay after ectopic overexpression and/or downregulation of miR-26a. Similarly, the expression levels of the miR-26a targets CASP3, CCNE2, ABL2, APAF1, XIAP, BCL-2, PTEN, p53, E2F3, CDC25A, BCL2L1, MCL-1, EZH2, and MTDH were assessed by quantitative polymerase chain reaction (PCR). The effect of metformin treatment on breast cancer cell viability and miR-26a, BCL-2, PTEN, MCL-1, EZH2, and MTDH modulation were evaluated. Wound healing experiments were performed to analyze the effect of miR-26a and metformin treatment on cell migration. MiR-26a overexpression resulted in a reduction in cell viability that was partially recovered by inhibiting it. E2F3, MCL-1, EZH2, MTDH, and PTEN were downregulated by miR-26a and the PTEN (phosphatase and tensin homolog) protein was also reduced after miR-26a overexpression. Metformin treatment reduced breast cancer cell viability, increased miR-26a expression, and led to a reduction in BCL-2, EZH2, and PTEN expression. miR-26a inhibition partly prevents the metformin viability effect and the PTEN and EZH2 expression reduction. Our results indicate that metformin effectively reduces breast cancer cell viability and suggests that the effects of the drug are mediated by an increase in miR-26a expression and a reduction of its targets, PTEN and EHZ2 Thus, the use of metformin in breast cancer treatment constitutes a promising potential breast cancer therapy.
Moorman AV New and emerging prognostic and predictive genetic biomarkers in B-cell precursor acute lymphoblastic leukemia. Haematologica. 2016; 101(4):407-16 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
Acute lymphoblastic leukemia (ALL) is a heterogeneous disease at the genetic level. Chromosomal abnormalities are used as diagnostic, prognostic and predictive biomarkers to provide subtype, outcome and drug response information. t(12;21)/ETV6-RUNX1 and high hyper-diploidy are good-risk prognostic biomarkers whereas KMT2A(MLL) translocations, t(17;19)/TCF3-HLF, haploidy or low hypodiploidy are high-risk biomarkers. t(9;22)/BCR-ABL1 patients require targeted treatment (imatinib/dasatinib), whereas iAMP21 patients achieve better outcomes when treated intensively. High-risk genetic biomarkers are four times more prevalent in adults compared to children. The application of genomic technologies to cases without an established abnormality (B-other) reveals copy number alterations which can be used either individually or in combination as prognostic biomarkers. Transcriptome sequencing studies have identified a network of fusion genes involving kinase genes -ABL1,ABL2,PDGFRB,CSF1R,CRLF2,JAK2 and EPOR in-vitro and in-vivo studies along with emerging clinical observations indicate that patients with a kinase-activating aberration may respond to treatment with small molecular inhibitors like imatinib/dasatinib and ruxolitinib. Further work is required to determine the true frequency of these abnormalities across the age spectrum and the optimal way to incorporate such inhibitors into protocols. In conclusion, genetic biomarkers are playing an increasingly important role in the management of patients with ALL.
Qin X, Wan Y, Wang S, Xue M MicroRNA-125a-5p modulates human cervical carcinoma proliferation and migration by targeting ABL2. Drug Des Devel Ther. 2016; 10:71-9 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
BACKGROUND: In this study, we intended to understand the regulatory mechanisms of microRNA-125a-5p (miR-125a-5p) in human cervical carcinoma. METHODS: The gene expressions of miR-125a-5p in seven cervical carcinoma cell lines and 12 human cervical carcinoma samples were evaluated by quantitative real-time reverse transcription polymerase chain reaction. Ca-Ski and HeLa cells were transduced with lentivirus carrying miR-125a-5p mimics, and the effects of lentivirus-induced miR-125a-5p upregulation on cervical carcinoma proliferation and migration were examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and transwell assays, respectively. In additional, HeLa cells were inoculated into null mice to evaluate the effect of miR-125a-5p upregulation on in vivo cervical carcinoma growth. The direct regulation of miR-125a-5p on its target gene, ABL proto-oncogene 2 (ABL2), in cervical carcinoma was evaluated by quantitative real-time reverse transcription polymerase chain reaction, Western blotting and luciferase reporter assays, respectively. ABL2 was then downregulated by small interfering RNA to examine its effect on cervical carcinoma proliferation and migration. RESULTS: miR-125a-5p was downregulated in both cervical carcinoma cell lines and human cervical carcinomas. In Ca-Ski and HeLa cells, lentivirus-mediated miR-125a-5p upregulation inhibited cancer proliferation and migration in vitro and cervical carcinoma transplantation in vivo. ABL2 was shown to be directly targeted by miR-125a-5p. In cervical carcinoma, ABL2 gene and protein levels were both downregulated by miR-125a-5p. Small interfering RNA-mediated ABL2 downregulation also had tumor-suppressive effects on cervical carcinoma proliferation and migration. CONCLUSION: The molecular pathway of miR-125a-5p/ABL2 plays an important role in human cervical carcinoma. Targeting miR-125a-5p/ABL2 pathway may provide a new treatment strategy for patients with cervical carcinoma.
Nakamura S, Kahyo T, Tao H, et al. Novel roles for LIX1L in promoting cancer cell proliferation through ROS1-mediated LIX1L phosphorylation. Sci Rep. 2015; 5:13474 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
Herein, we report the characterization of Limb expression 1-like, (LIX1L), a putative RNA-binding protein (RBP) containing a double-stranded RNA binding motif, which is highly expressed in various cancer tissues. Analysis of MALDI-TOF/TOF mass spectrometry and RNA immunoprecipitation-sequencing of interacting proteins and the microRNAs (miRNAs) bound to LIX1L revealed that LIX1L interacts with proteins (RIOK1, nucleolin and PABPC4) and miRNAs (has-miRNA-520a-5p, -300, -216b, -326, -190a, -548b-3p, -7-5p and -1296) in HEK-293 cells. Moreover, the reduction of phosphorylated Tyr(136) (pTyr(136)) in LIX1L through the homeodomain peptide, PY136, inhibited LIX1L-induced cell proliferation in vitro, and PY136 inhibited MKN45 cell proliferation in vivo. We also determined the miRNA-targeted genes and showed that was apoptosis induced through the reduction of pTyr(136). Moreover, ROS1, HCK, ABL1, ABL2, JAK3, LCK and TYR03 were identified as candidate kinases responsible for the phosphorylation of Tyr(136) of LIX1L. These data provide novel insights into the biological significance of LIX1L, suggesting that this protein might be an RBP, with implications for therapeutic approaches for targeting LIX1L in LIX1L-expressing cancer cells.
Kim IW, Han N, Kim MG, et al. Copy number variability analysis of pharmacogenes in patients with lymphoma, leukemia, hepatocellular, and lung carcinoma using The Cancer Genome Atlas data. Pharmacogenet Genomics. 2015; 25(1):1-7 [PubMed] Related Publications
OBJECTIVE: Individual differences in drug efficacy and toxicity remain an important clinical concern. We investigated copy number variation (CNV) frequencies for pharmacogenes using The Cancer Genome Atlas dataset. MATERIALS AND METHODS: One hundred and fifty-two pharmacogenes were selected from liver hepatocellular carcinoma, lung squamous cell carcinoma (LUSC), acute myeloid leukemia, and lymphoid neoplasm diffuse large B-cell lymphoma (DLBL). The germ line and somatic CNV frequencies were analyzed. RESULTS: We found CNVs with more than 1% frequency in drug-metabolizing enzymes including CYP2A6, CYP2D6, GSTP1, CYP2E1, GSTM1, GSTT1, and SULT1A1, drug transporters such as SLC19A1 and SLC28A1, and targets such as FHIT in normal tissue or blood. GSTM1 had the highest frequency for gene gain (45.45, 39.18, 31.01, and 34.77%, respectively) and for gene loss (18.18, 29.38, 20.89, and 26.68%, respectively) in DLBL, acute myeloid leukemia, liver hepatocellular carcinoma, and LUSC. P2RY12 and P2RY1 had the highest frequency for gene gain in LUSC (26.95 and 26.68%, respectively) whereas ABCB1 and ABL2 had the highest frequency for gene gain in DLBL (27.27%) in cancer tissue or blood. CONCLUSION: Germ line and somatic CNVs of pharmacogenes may play a role in determining individual variations in drug responses. Inclusion of CNVs in pharmacogenetic variations holds promise as biomarkers that can increase the benefits and reduce the risks of drug therapy on an individual level.
Roberts KG, Li Y, Payne-Turner D, et al. Targetable kinase-activating lesions in Ph-like acute lymphoblastic leukemia. N Engl J Med. 2014; 371(11):1005-15 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
BACKGROUND: Philadelphia chromosome-like acute lymphoblastic leukemia (Ph-like ALL) is characterized by a gene-expression profile similar to that of BCR-ABL1-positive ALL, alterations of lymphoid transcription factor genes, and a poor outcome. The frequency and spectrum of genetic alterations in Ph-like ALL and its responsiveness to tyrosine kinase inhibition are undefined, especially in adolescents and adults. METHODS: We performed genomic profiling of 1725 patients with precursor B-cell ALL and detailed genomic analysis of 154 patients with Ph-like ALL. We examined the functional effects of fusion proteins and the efficacy of tyrosine kinase inhibitors in mouse pre-B cells and xenografts of human Ph-like ALL. RESULTS: Ph-like ALL increased in frequency from 10% among children with standard-risk ALL to 27% among young adults with ALL and was associated with a poor outcome. Kinase-activating alterations were identified in 91% of patients with Ph-like ALL; rearrangements involving ABL1, ABL2, CRLF2, CSF1R, EPOR, JAK2, NTRK3, PDGFRB, PTK2B, TSLP, or TYK2 and sequence mutations involving FLT3, IL7R, or SH2B3 were most common. Expression of ABL1, ABL2, CSF1R, JAK2, and PDGFRB fusions resulted in cytokine-independent proliferation and activation of phosphorylated STAT5. Cell lines and human leukemic cells expressing ABL1, ABL2, CSF1R, and PDGFRB fusions were sensitive in vitro to dasatinib, EPOR and JAK2 rearrangements were sensitive to ruxolitinib, and the ETV6-NTRK3 fusion was sensitive to crizotinib. CONCLUSIONS: Ph-like ALL was found to be characterized by a range of genomic alterations that activate a limited number of signaling pathways, all of which may be amenable to inhibition with approved tyrosine kinase inhibitors. Trials identifying Ph-like ALL are needed to assess whether adding tyrosine kinase inhibitors to current therapy will improve the survival of patients with this type of leukemia. (Funded by the American Lebanese Syrian Associated Charities and others.).
Qiang XF, Zhang ZW, Liu Q, et al. miR-20a promotes prostate cancer invasion and migration through targeting ABL2. J Cell Biochem. 2014; 115(7):1269-76 [PubMed] Related Publications
The aberrant expression of microRNAs (miRNAs) has been found in various types of cancer. The present study found miR-20a was significantly up-regulated in prostate cancer compared with normal prostate tissues. Patients with a higher miR-20a expression had a Gleason score of 7-10 and shorter survival time. The transwell and wound healing assays revealed that blocking expression of miR-20a by miR-20a ASO suppresses the invasion and migration of PC-3 and DU145 cells in vitro and also inhibits tumor growth in vivo. Furthermore, we identified miR-20a directly targets the ABL family non-receptor tyrosine kinases ABL2 and negatively regulates the phosphorylation of its downstream gene p190RhoGAP. Knockdown of ABL2 promoted cell invasion and migration and we identified miR-20a-induced cell invasion and migration can be rescued by ABL2. In conclusion, our findings show that miR-20a significantly contributes to the progression of prostate cancer by targeting ABL2.
Arora S, Saini S, Fukuhara S, et al. MicroRNA-4723 inhibits prostate cancer growth through inactivation of the Abelson family of nonreceptor protein tyrosine kinases. PLoS One. 2013; 8(11):e78023 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
The Abelson (c-Abl) proto-oncogene encodes a highly conserved nonreceptor protein tyrosine kinase that plays a role in cell proliferation, differentiation, apoptosis and cell adhesion. c-Abl represents a specific anti-cancer target in prostate cancer as aberrant activity of this kinase has been implicated in the stimulation of prostate cancer growth and progression. However, the mechanism of regulation of c-Abl is not known. Here we report that Abl kinases are regulated by a novel microRNA, miR-4723, in prostate cancer. Expression profiling of miR-4723 expression in a cohort of prostate cancer clinical specimens showed that miR-4723 expression is widely attenuated in prostate cancer. Low miR-4723 expression was significantly correlated with poor survival outcome and our analyses suggest that miR-4723 has significant potential as a disease biomarker for diagnosis and prognosis in prostate cancer. To evaluate the functional significance of decreased miR-4723 expression in prostate cancer, miR-4723 was overexpressed in prostate cancer cell lines followed by functional assays. miR-4723 overexpression led to significant decreases in cell growth, clonability, invasion and migration. Importantly, miR-4723 expression led to dramatic induction of apoptosis in prostate cancer cell lines suggesting that miR-4723 is a pro-apoptotic miRNA regulating prostate carcinogenesis. Analysis of putative miR-4723 targets showed that miR-4723 targets integrin alpha 3 and Methyl CpG binding protein in addition to Abl1 and Abl2 kinases. Further, we found that the expression of Abl kinase is inversely correlated with miR-4723 expression in prostate cancer clinical specimens. Also, Abl1 knockdown partially phenocopies miR-4723 reexpression in prostate cancer cells suggesting that Abl is a functionally relevant target of miR-4723 in prostate cancer. In conclusion, we have identified a novel microRNA that mediates regulation of Abl kinases in prostate cancer. This study suggests that miR-4723 may be an attractive target for therapeutic intervention in prostate cancer.
He M, Fan J, Jiang R, et al. Expression of DNMTs and genomic DNA methylation in gastric signet ring cell carcinoma. Mol Med Rep. 2013; 8(3):942-8 [PubMed] Related Publications
The aim of the present study was to investigate the protein expression of DNA methyltransferases (DNMTs) and genomic DNA methylation status of genomes in gastric signet ring cell carcinoma (SRC). Immunohistochemistry was performed to analyze DNMT expression and methylated DNA immunoprecipitation microarray (MeDIP‑chip) and MeDIP quantitative real‑time PCR (MeDIP‑qPCR) were performed to analyze the genomic DNA methylation status in gastric SRC tissue. An increase in DNMT1 and decrease in DNMT3A expression in SRC tissue was observed compared with matched non‑cancerous tissue. However, expression of other DNMTs, DNMT2, DNMT3B and DNMT3L, was not found to differ significantly between carcinoma and control. The MeDIP‑chip assay revealed that methylation of gene promoters and CpG islands in SRC was higher than those in matched control tissue. However, MeDIP‑qPCR analysis demonstrated that specific tumor‑related genes, including ABL2, FGF18, TRAF2, EGFL7 and RAB33A were aberrantly hypomethylated in SRC tissue. Results of the current study indicate that gastric SRC may produce complex patterns of aberrant DNA methylation and DNMT expression.
He H, Wu G, Liu H, et al. Low RIN1 expression in HCC is associated with tumor invasion and unfavorable prognosis. Am J Clin Pathol. 2013; 140(1):73-81 [PubMed] Related Publications
OBJECTIVES: To explore the association between the expression of Ras and Rab interactor 1 (RIN1) and the prognosis of hepatocellular carcinoma (HCC). METHODS: RIN1 expression was detected in paired HCC tissues by real-time polymerase chain reaction, Western blot analysis, and immunohistochemistry. Transfection was applied to analyze the RIN1 function. RESULTS: We found that expression of the RIN1 protein was downregulated in the HCC samples compared with the corresponding normal tissues. Downregulation of RIN1 expression was also associated with invasion and poor overall survival (OS). The results of our multivariate analysis indicated that the RIN1 status is a significant prognostic factor for OS. RIN1 overexpression also inhibited cell invasion in HepG2 cells. The expression between RIN1 and ABL2 may present a positive correlation. CONCLUSIONS: Our results demonstrate that RIN1 suppresses tumor invasion in HCC patients and that a poor prognosis for HCC is expected when RIN1 expression is downregulated.
Ross RW, Galsky MD, Scher HI, et al. A whole-blood RNA transcript-based prognostic model in men with castration-resistant prostate cancer: a prospective study. Lancet Oncol. 2012; 13(11):1105-13 [PubMed] Related Publications
BACKGROUND: Survival for patients with castration-resistant prostate cancer is highly variable. We assessed the effectiveness of a whole-blood RNA transcript-based model as a prognostic biomarker in castration-resistant prostate cancer. METHODS: Peripheral blood was prospectively collected from 62 men with castration-resistant prostate cancer on various treatment regimens who were enrolled in a training set at the Dana-Farber Cancer Institute (Boston, MA, USA) from August, 2006, to June, 2008, and from 140 patients with castration-resistant prostate cancer in a validation set from Memorial Sloan-Kettering Cancer Center (New York, NY, USA) from August, 2006, to February, 2009. A panel of 168 inflammation-related and prostate cancer-related genes was assessed with optimised quantitative PCR to assess biomarkers predictive of survival. FINDINGS: A six-gene model (consisting of ABL2, SEMA4D, ITGAL, and C1QA, TIMP1, CDKN1A) separated patients with castration-resistant prostate cancer into two risk groups: a low-risk group with a median survival of more than 34·9 months (median survival was not reached) and a high-risk group with a median survival of 7·8 months (95% CI 1·8-13·9; p<0·0001). The prognostic utility of the six-gene model was validated in an independent cohort. This model was associated with a significantly higher area under the curve compared with a clinicopathological model (0·90 [95% CI 0·78-0·96] vs 0·65 [0·52-0·78]; p=0·0067). INTERPRETATION: Transcriptional profiling of whole blood yields crucial prognostic information about men with castration-resistant prostate cancer. The six-gene model suggests possible dysregulation of the immune system, a finding that warrants further study. FUNDING: Source MDX.
Kaczkowski B, Rossing M, Andersen DK, et al. Integrative analyses reveal novel strategies in HPV11,-16 and -45 early infection. Sci Rep. 2012; 2:515 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
The interaction between human papillomavirus (HPV) and host cells is not well understood. We investigate the early stage of HPV infections by global expression profiling in a cell model, in which HaCaT cells were transfected with HPV11, HPV16 or HPV45 genomes. We report the differential expression of genes not previously implicated in HPV biology, such as the PSG family and ANKRD1, and of genes implicated in the biology of other viruses, e.g. MX1, IFI44 and DDX60. Carcinogenesis-related genes, e.g. ABL2, MGLL and CYR61, were upregulated by high-risk HPV16 and -45. The integrative analysis revealed the suppression of DNA repair by HPV11 and -16, and downregulation of cytoskeleton genes by all HPV types. Various signalling pathways were affected by the HPVs: IL-2 by HPV11; JAK-STAT by HPV16; and TGF-β, NOTCH and tyrosine kinase signalling by HPV45. This study uncovered novel strategies employed by HPV to establish infection and promote uncontrolled growth.
Gil-Henn H, Patsialou A, Wang Y, et al. Arg/Abl2 promotes invasion and attenuates proliferation of breast cancer in vivo. Oncogene. 2013; 32(21):2622-30 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
Tumor progression is a complex, multistep process involving accumulation of genetic aberrations and alterations in gene expression patterns leading to uncontrolled cell division, invasion into surrounding tissue and finally dissemination and metastasis. We have previously shown that the Arg/Abl2 non-receptor tyrosine kinase acts downstream of the EGF receptor and Src tyrosine kinases to promote invadopodium function in breast cancer cells, thereby promoting their invasiveness. However, whether and how Arg contributes to tumor development and dissemination in vivo has never been investigated. Using a mouse xenograft model, we show that knocking down Arg in breast cancer cells leads to increased tumor cell proliferation and significantly enlarged tumor size. Despite having larger tumors, the Arg-knockdown (Arg KD) tumor-bearing mice exhibit significant reductions in tumor cell invasion, intravasation into blood vessels and spontaneous metastasis to lungs. Interestingly, we found that proliferation-associated genes in the Ras-MAPK (mitogen-activated protein kinase) pathway are upregulated in Arg KD breast cancer cells, as is Ras-MAPK signaling, while invasion-associated genes are significantly downregulated. These data suggest that Arg promotes tumor cell invasion and dissemination, while simultaneously inhibiting tumor growth. We propose that Arg acts as a switch in metastatic cancer cells that governs the decision to 'grow or go' (divide or invade).
Zhou MH, Gao L, Jing Y, et al. Detection of ETV6 gene rearrangements in adult acute lymphoblastic leukemia. Ann Hematol. 2012; 91(8):1235-43 [PubMed] Related Publications
ETV6 is an important hematopoietic regulatory factor and ETV6 gene rearrangement is involved in a wide variety of hematological malignancies. In this study, we sought to investigate the incidence of ETV6-associated fusion genes in B- and T-lineage acute lymphoblastic leukemia (ALL) by multiplex-nested reverse transcription-polymerase chain reaction (RT-PCR) in 176 adult ALL patients. Total RNA was extracted from bone marrow samples of ALL patients including 136 B- and 40 T-lineage ALL, and ETV6 fusion genes were detected by multiplex-nested RT-PCR. Changes of ETV6 fusion gene mRNA transcript levels were examined by real-time RT-PCR. We detected a total of 15 ETV6 gene rearrangements with a positive rate of 8.5%, involving seven ETV6-associated fusion genes in 13 B-ALL (13/136, 9.6%) and 2 T-ALL patients (2/40, 5.0%). ETV6-RUNX1 were observed in six cases (3.4%), ETV6-JAK2 in three cases (1.7%), ETV6-ABL1 in two cases (1.1%), and ETV6-ABL2, ETV6-NCOA2, ETV6-SYK, and PAX5-ETV6 each in one case (0.6%). ETV6-JAK2 was found in both B-ALL and T-ALL patients. Furthermore, real-time quantitative RT-PCR assays showed that the ETV6-RUNX1 mRNA transcript levels decreased during conventional chemotherapy or hematopoietic stem cell transplantation. This study shows that multiplex-nested RT-PCR is an effective and accurate tool to identify ETV6 rearrangements in adult ALL, which provides some clues into the diagnosis and prognosis of ALL but also molecular markers for the detection of minimal residual disease in adult ALL.
Behbahani TE, Thierse C, Baumann C, et al. Tyrosine kinase expression profile in clear cell renal cell carcinoma. World J Urol. 2012; 30(4):559-65 [PubMed] Related Publications
PURPOSE: To profile different tyrosine kinase (TK) expression patterns in clear cell renal carcinoma (ccRCC). METHODS: We analysed mRNA expression levels of 89 receptor and non-receptor TK in corresponding cancer and normal renal tissue from 5 patients with ccRCC using the TaqMan Low-Density Array technology. In order to confirm aberrant TK expressions, a subsequent analysis of 25 ccRCC and corresponding normal renal tissues was performed, applying quantitative real-time PCR. To confirm mRNA expression levels on protein level, we studied ERBB4 and HCK using immunohistochemistry. RESULTS: A total of 12 TK were significantly upregulated in ccRCC (ABL2, FLT1, BTK, HCK, JAK3, CSF1R, MET, JAK1, MATK, PTPRC, FYN and CSK), coherently 7 TK demonstrated a down-regulation (ERBB4, PDGFRA, NRTK3, SYK, ERBB2, FGFR3 and PTK7). These findings were validated by the utilization of RT-PCR for ABL2, FLT1 BTK, HCK, JAK3, CSF1R, MET, JAK1, MATK and vice versa for ERBB4 and PDGFRA. Immunohistochemistry revealed ERBB4 expression to be significantly lower in ccRCC in comparison to papillary RCC, chromophobe RCC, renal oncocytoma and normal renal tissue (P < 0.001). HCK protein expression was reduced in ccRCC in contrast to papillary RCC (P < 0.001) or oncocytoma (P = 0.023), but similar to chromphobe RCC (P = 0.470), sarcomatoid RCC (P = 0.754) and normal renal tissue (P = 0.083). Neither ERBB4 nor HCK were correlated (P > 0.05) with clinical-pathological parameters. CONCLUSION: TK constitute valuable targets for pharmaceutical anti-cancer therapy. ERBB4 and HCK depict significantly lower expression levels in renal cancer tissues.
Sos ML, Michel K, Zander T, et al. Predicting drug susceptibility of non-small cell lung cancers based on genetic lesions. J Clin Invest. 2009; 119(6):1727-40 [PubMed] Article available free on PMC after 01/01/2020 Related Publications
Somatic genetic alterations in cancers have been linked with response to targeted therapeutics by creation of specific dependency on activated oncogenic signaling pathways. However, no tools currently exist to systematically connect such genetic lesions to therapeutic vulnerability. We have therefore developed a genomics approach to identify lesions associated with therapeutically relevant oncogene dependency. Using integrated genomic profiling, we have demonstrated that the genomes of a large panel of human non-small cell lung cancer (NSCLC) cell lines are highly representative of those of primary NSCLC tumors. Using cell-based compound screening coupled with diverse computational approaches to integrate orthogonal genomic and biochemical data sets, we identified molecular and genomic predictors of therapeutic response to clinically relevant compounds. Using this approach, we showed that v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations confer enhanced Hsp90 dependency and validated this finding in mice with KRAS-driven lung adenocarcinoma, as these mice exhibited dramatic tumor regression when treated with an Hsp90 inhibitor. In addition, we found that cells with copy number enhancement of v-abl Abelson murine leukemia viral oncogene homolog 2 (ABL2) and ephrin receptor kinase and v-src sarcoma (Schmidt-Ruppin A-2) viral oncogene homolog (avian) (SRC) kinase family genes were exquisitely sensitive to treatment with the SRC/ABL inhibitor dasatinib, both in vitro and when it xenografted into mice. Thus, genomically annotated cell-line collections may help translate cancer genomics information into clinical practice by defining critical pathway dependencies amenable to therapeutic inhibition.