LCK

Gene Summary

Gene:LCK; LCK proto-oncogene, Src family tyrosine kinase
Aliases: LSK, YT16, IMD22, p56lck, pp58lck
Location:1p35.2
Summary:This gene is a member of the Src family of protein tyrosine kinases (PTKs). The encoded protein is a key signaling molecule in the selection and maturation of developing T-cells. It contains N-terminal sites for myristylation and palmitylation, a PTK domain, and SH2 and SH3 domains which are involved in mediating protein-protein interactions with phosphotyrosine-containing and proline-rich motifs, respectively. The protein localizes to the plasma membrane and pericentrosomal vesicles, and binds to cell surface receptors, including CD4 and CD8, and other signaling molecules. Multiple alternatively spliced variants encoding different isoforms have been described. [provided by RefSeq, Aug 2016]
Databases:OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:tyrosine-protein kinase Lck
Source:NCBIAccessed: 01 September, 2019

Ontology:

What does this gene/protein do?
Show (53)
Pathways:What pathways are this gene/protein implicaed in?
Show (8)

Cancer Overview

Research Indicators

Publications Per Year (1994-2019)
Graph generated 01 September 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.

  • Cell Proliferation
  • Proto-Oncogene Proteins
  • Messenger RNA
  • Membrane Proteins
  • Lymphocyte Specific Protein Tyrosine Kinase p56(lck)
  • Transfection
  • T-Cell Lymphoma
  • Lymphoma
  • beta Catenin
  • Signal Transduction
  • Oncogenes
  • Molecular Sequence Data
  • Mutation
  • Neoplastic Cell Transformation
  • Gene Expression
  • T-Lymphocytes, Cytotoxic
  • T-Cell Leukemia
  • B-Lymphocytes
  • Receptors, Tumor Necrosis Factor
  • Cancer RNA
  • DNA-Binding Proteins
  • Thymus Neoplasms
  • Promoter Regions
  • Cell Line
  • Chromosome 1
  • Proto-Oncogene Proteins pp60(c-src)
  • bcl-X Protein
  • Mice, Transgenic
  • Leukemic Gene Expression Regulation
  • T-Lymphocytes
  • Protein-Tyrosine Kinases
  • Oligonucleotide Array Sequence Analysis
  • Translocation
  • Northern Blotting
  • Gene Expression Profiling
  • Biomarkers, Tumor
  • Transcriptome
  • Base Sequence
  • Cancer Gene Expression Regulation
  • Phosphorylation
Tag cloud generated 01 September, 2019 using data from PubMed, MeSH and CancerIndex

Latest Publications: LCK (cancer-related)

Dong F, Yang Q, Wu Z, et al.
Identification of survival-related predictors in hepatocellular carcinoma through integrated genomic, transcriptomic, and proteomic analyses.
Biomed Pharmacother. 2019; 114:108856 [PubMed] Related Publications
Patient survival time generally reflects the tumor progression and represents a key clinical parameter. In this study, we aimed to comprehensively characterize the prognosis-associated molecular alterations in hepatocellular carcinoma (HCC). In this study, copy-number changes, gene mutations, mRNA expression, and reverse phase protein arrays data in HCC samples profiled by The Cancer Genome Atlas (TCGA) were obtained. Tumors were then stratified into two groups based on the clinical outcome and identified genomic, transcriptomic, and proteomic traits associated to HCC prognosis. We found that several copy number amplifications and deletions can discriminate HCC patients with poor prognosis from those with better prognosis. Mutated DNAH8 showed a worse prognosis-specific pattern and correlated with a reduced disease-free survival in HCC. By integrating RNA sequencing data, we found that HCC samples with poor prognosis are consistently associated with the up-regulation of cell cycle process, such as chromosome separation, DNA replication, cytokinesis, and etc. At the proteomic level, seven proteins were significantly enriched in samples with poor prognosis, including acetylated α-Tubulin, p62-LCK-ligand, ARID1 A, MSH6, B-Raf, Cyclin B1, and PEA15. Acetylated α-Tubulin was frequently expressed in HCC tissues and acted as a promising prognostic factor for HCC. These alterations lay a foundation for developing relevant therapeutic strategies and improve our knowledge of the pathogenesis of HCC.

Fuchs AR, Märklin M, Heitmann JS, et al.
A Chromatin Immunoprecipitation Assay to Identify Novel NFAT2 Target Genes in Chronic Lymphocytic Leukemia.
J Vis Exp. 2018; (142) [PubMed] Related Publications
Chronic lymphocytic leukemia (CLL) is characterized by the expansion of malignant B cell clones and represents the most common leukemia in western countries. The majority of CLL patients show an indolent course of the disease as well as an anergic phenotype of their leukemia cells, referring to a B cell receptor unresponsive to external stimulation. We have recently shown that the transcription factor NFAT2 is a crucial regulator of anergy in CLL. A major challenge in the analysis of the role of a transcription factor in different diseases is the identification of its specific target genes. This is of great significance for the elucidation of pathogenetic mechanisms and potential therapeutic interventions. Chromatin immunoprecipitation (ChIP) is a classic technique to demonstrate protein-DNA interactions and can, therefore, be used to identify direct target genes of transcription factors in mammalian cells. Here, ChIP was used to identify LCK as a direct target gene of NFAT2 in human CLL cells. DNA and associated proteins are crosslinked using formaldehyde and subsequently sheared by sonication into DNA fragments of approximately 200-500 base pairs (bp). Cross-linked DNA fragments associated with NFAT2 are then selectively immunoprecipitated from cell debris using an αNFAT2 antibody. After purification, associated DNA fragments are detected via quantitative real-time PCR (qRT-PCR). DNA sequences with evident enrichment represent regions of the genome which are targeted by NFAT2 in vivo. Appropriate shearing of the DNA and the selection of the required antibody are particularly crucial for the successful application of this method. This protocol is ideal for the demonstration of direct interactions of NFAT2 with target genes. Its major limitation is the difficulty to employ ChIP in large-scale assays analyzing the target genes of multiple transcription factors in intact organisms.

Tan P, Ye Y, He L, et al.
TRIM59 promotes breast cancer motility by suppressing p62-selective autophagic degradation of PDCD10.
PLoS Biol. 2018; 16(11):e3000051 [PubMed] Free Access to Full Article Related Publications
Cancer cells adopt various modes of migration during metastasis. How the ubiquitination machinery contributes to cancer cell motility remains underexplored. Here, we report that tripartite motif (TRIM) 59 is frequently up-regulated in metastatic breast cancer, which is correlated with advanced clinical stages and reduced survival among breast cancer patients. TRIM59 knockdown (KD) promoted apoptosis and inhibited tumor growth, while TRIM59 overexpression led to the opposite effects. Importantly, we uncovered TRIM59 as a key regulator of cell contractility and adhesion to control the plasticity of metastatic tumor cells. At the molecular level, we identified programmed cell death protein 10 (PDCD10) as a target of TRIM59. TRIM59 stabilized PDCD10 by suppressing RING finger and transmembrane domain-containing protein 1 (RNFT1)-induced lysine 63 (K63) ubiquitination and subsequent phosphotyrosine-independent ligand for the Lck SH2 domain of 62 kDa (p62)-selective autophagic degradation. TRIM59 promoted PDCD10-mediated suppression of Ras homolog family member A (RhoA)-Rho-associated coiled-coil kinase (ROCK) 1 signaling to control the transition between amoeboid and mesenchymal invasiveness. PDCD10 overexpression or administration of a ROCK inhibitor reversed TRIM59 loss-induced contractile phenotypes, thereby accelerating cell migration, invasion, and tumor formation. These findings establish the rationale for targeting deregulated TRIM59/PDCD10 to treat breast cancer.

Zepecki JP, Snyder KM, Moreno MM, et al.
Regulation of human glioma cell migration, tumor growth, and stemness gene expression using a Lck targeted inhibitor.
Oncogene. 2019; 38(10):1734-1750 [PubMed] Free Access to Full Article Related Publications
Migration of human glioma cells (hGCs) within the brain parenchyma makes glioblastoma one of the most aggressive and lethal tumors. Studies of the cellular and molecular mechanisms underlying hGC migration are hindered by the limitations of existing glioma models. Here we developed a dorsal root ganglion axon-oligodendrocyte-hGC co-culture to study in real time the migration and interaction of hGCs with their microenvironment. hGCs interact with myelinated and non-myelinated axons through the formation of pseudopodia. Isolation of pseudopodia-localized polysome-bound RNA reveals transcripts of Lck, Paxillin, Crk-II, and Rac1 that undergo local translation. Inhibition of Lck phosphorylation using a small-molecule inhibitor (Lck-I), blocks the phosphorylation of Paxillin and Crk-II, the formation of pseudopodia and the migration of hGCs. In vivo intraventricular administration of the Lck-I using an orthotopic xenograft glioma model, results in statistically significant inhibition of tumor size and significant down-regulation of Nanog-targeted genes, which are associated with glioblastoma patient survival. Moreover, treatment of human glioma stem cells (hGSCs) with Lck-I, results in significant inhibition of self-renewal and tumor-sphere formation. The involvement of Lck in different levels of glioma malignant progression, such as migration, tumor growth, and regulation of cancer stemness, makes Lck a potentially important therapeutic target for human glioblastomas.

Moirangthem A, Wang X, Yan IK, Patel T
Network analyses-based identification of circular ribonucleic acid-related pathways in intrahepatic cholangiocarcinoma.
Tumour Biol. 2018; 40(9):1010428318795761 [PubMed] Related Publications
Circular ribonucleic acids are non-coding ribonucleic acids that can be identified from genome sequencing studies. Although they can be readily detected, their regulation and functional role in human diseases such as cancer are unknown. Using a systematic approach, we analyzed ribonucleic acid-sequencing data from a well-characterized cohort of intrahepatic cholangiocarcinoma to identify genetic pathways related to circular ribonucleic acids. Although the expression of most circular ribonucleic acids was similar in both the cancer and non-cancer tissues, expression of circ2174 was significantly increased in cancer tissues. Network analysis of co-related genes identified several pathways associated with circ2174, and common regulatory mediators between genes in these pathways and circ2174. Among these, alterations in several genes involved in interleukin-16 signaling responses such Lck, interleukin-16, and macrophage inflammatory protein-1-beta were the most prominent. Octamer transcription factor (Oct)-2 was identified as a signal transducer that was common to both circ2174 and interleukin-16. Circ2174 has sequence complementarity to miR149 which can target Oct-2. These data suggest a mechanism whereby circ2174 can act as a sponge to regulate the expression of miR149, and thereby modulate Oct-2 and interleukin-16 signaling pathways in cholangiocarcinoma.

Miyata-Takata T, Chuang SS, Takata K, et al.
Expression of T-cell receptor signalling pathway components in extranodal NK/T-cell lymphoma.
Histopathology. 2018; 73(6):1030-1038 [PubMed] Related Publications
AIMS: Although the neoplastic cells of extranodal natural killer (NK)/T-cell lymphoma (ENKTL) usually do not express T-cell antigens, the T-cell receptor (TCR) gene might be rearranged and TCR protein expressed. The aim is to elucidate the expression of the downstream TCR pathway components and their importance in ENKTL.
METHODS AND RESULTS: We used formalin-fixed paraffin-embedded tissues from 91 ENKTL samples to immunohistochemically characterise the expression of TCR pathway components. The following proteins were variably expressed: ZAP70 (94%; 83/88), GRAP2/GADS (68%; 60/88), DOK2 (42%; 38/90), LCK (35%; 31/88), and ITK (10%; 9/90). When these tumours were classified as being of T lineage (16%), NK lineage (45%), or indeterminate lineage (38%), the GRAP2/GADS expression rate was higher in T lineage tumours (versus NK, P = 0.0073; versus indeterminate, P = 0.00082). GRAP2/GADS-positive NK lineage tumours more frequently expressed DOK2 (P = 0.0073), and were more often confined to the nasal areas (P = 0.014). Furthermore, when these tumours were immunophenotypically classified into a T signature (42%) or NK signature (58%), the expression rates of GRAP2/GADS and ITK were higher in T signature tumours (P = 0.00074 and P = 0.067, respectively), whereas that of LCK was higher in NK-signature tumours (P = 0.10).
CONCLUSIONS: Although some ENTKL cases were polyclonal for TCR rearrangement and others lacked TCR expression, we speculate that the TCR pathway might be functioning in ENKTLs. A T signature versus a NK signature might be better for delineating the physiology of ENKTL than cellular lineage. Furthermore, ITK may represent a potential therapeutic target for patients with ITK-expressing tumours.

Lee SR, Choi YD, Cho NH
Association between pathologic factors and ERG expression in prostate cancer: finding pivotal networking.
J Cancer Res Clin Oncol. 2018; 144(9):1665-1683 [PubMed] Related Publications
PURPOSE: To evaluate associations between pathologic factors and erythroblast transformation-specific (ETS)-related gene (ERG) expression in prostate cancer patients. Using next-generation sequencing, we identified target genes and regulatory networks.
METHODS: ERG expression in 60 radical prostatectomies was compared with pathological findings by association rule mining with the Apriori algorithm. Whole-exome and RNA sequencing were performed on three formalin-fixed, paraffin-embedded ERG-positive and negative prostate cancer samples. A network diagram identifying dominant altered genes was constructed using Cytoscape open-source bioinformatics platform and GeneMania plugin.
RESULTS: Pathologic conditions positive for perineural invasion, apical margins, and Gleason score 3 + 4 = 7 were significantly more likely to be ERG-positive than other pathologic conditions (p = 0.0008), suggesting an association between ERG positivity, perineural invasion, apical margins, and Gleason score 3 + 4 = 7 (Firth's logistic regression: OR 42.565, 95% CI 1.670-1084.847, p = 0.0232). Results of whole-exome and RNA sequencing identified 97 somatic mutations containing common mutated genes. Regulatory network analysis identified NOTCH1, MEF2C, STAT3, LCK, CACNA2D3, PCSK7, MEF2A, PDZD2, TAB1, and ASGR1 as pivotal genes. NOTCH1 appears to function as a hub, because it had the highest node degree and betweenness. NOTCH1 staining was found 8 of 60 specimens (13%), with a significant association between ERG and NOTCH1 positivity (p = 0.001).
CONCLUSIONS: Evaluating the association between ERG expression and pathologic factors, and identifying the regulatory network and pivotal hub may help to understand the clinical significance of ERG-positive prostate cancer.

Sugihara T, Werneburg NW, Hernandez MC, et al.
YAP Tyrosine Phosphorylation and Nuclear Localization in Cholangiocarcinoma Cells Are Regulated by LCK and Independent of LATS Activity.
Mol Cancer Res. 2018; 16(10):1556-1567 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
The Hippo pathway effector, Yes-associated protein (YAP), is a transcriptional coactivator implicated in cholangiocarcinoma (CCA) pathogenesis. YAP is known to be regulated by a serine/threonine kinase relay module (MST1/2-LATS1/2) culminating in phosphorylation of YAP at Serine 127 and cytoplasmic sequestration. However, YAP also undergoes tyrosine phosphorylation, and the role of tyrosine phosphorylation in YAP regulation remains unclear. Herein, YAP regulation by tyrosine phosphorylation was examined in human and mouse CCA cells, as well as patient-derived xenograft (PDX) models. YAP was phosphorylated on tyrosine 357 (Y357) in CCA cell lines and PDX models. SRC family kinase (SFK) inhibition with dasatinib resulted in loss of YAPY357 phosphorylation, promoted its translocation from the nucleus to the cytoplasm, and reduced YAP target gene expression, including cell lines expressing a LATS1/2-resistant YAP mutant in which all serine residues were mutated to alanine. Consistent with these observations, precluding YAPY357 phosphorylation by site-directed mutagenesis (YAPY357F) excluded YAP from the nucleus. Targeted siRNA experiments identified LCK as the SFK that most potently mediated YAPY357 phosphorylation. Likewise, inducible CRISPR/Cas9-targeted LCK deletion decreased YAPY357 phosphorylation and its nuclear localization. The importance of LCK in CCA biology was demonstrated by clinical observations suggesting LCK expression levels were associated with early tumor recurrence following resection of CCA. Finally, dasatinib displayed therapeutic efficacy in PDX models.

Wang PF, Cai HQ, Zhang CB, et al.
Molecular and clinical characterization of PTPN2 expression from RNA-seq data of 996 brain gliomas.
J Neuroinflammation. 2018; 15(1):145 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
BACKGROUND: Immune checkpoint inhibitors have been shown to promote antitumor immunity and achieve durable tumor remissions. However, certain tumors are refractory to current immunotherapy. These negative results encouraged us to uncover other therapeutic targets and strategies. PTPN2 (protein tyrosine phosphatase, non-receptor type 2) has been newly identified as an immunotherapy target. Loss of PTPN2 sensitizes the tumor to immunotherapy via IFNγ signaling.
METHODS: Here, we investigated the relationship between PTPN2 mRNA levels and clinical characteristics in gliomas. RNA-seq data of a cohort of 325 patients with glioma were available from the Chinese Glioma Genome Atlas and 671 from The Cancer Genome Atlas. R language, GraphPad Prism 5, and SPSS 22.0 were used to analyze data and draw figures.
RESULTS: PTPN2 transcript levels increased significantly with higher grades of glioma and in isocitrate dehydrogenase (IDH) wild-type and mesenchymal subtype gliomas. A comprehensive biological analysis was conducted, which indicated a crucial role of PTPN2 in the immune and inflammation responses in gliomas. Specifically, PTPN2 was positively associated with HCK, LCK, MHC II, and STAT1 but negatively related to IgG and interferon. Moreover, canonical correlation analysis showed a positive correlation of PTPN2 with infiltrating immune cells, such as macrophages, neutrophils, and CD8
CONCLUSION: PTPN2 expression level was increased in glioblastomas and associated with gliomas of the IDH wild-type and mesenchymal subtype. There was a close correlation between PTPN2 and the immune response and inflammatory activity in gliomas. Our results show that PTPN2 is a promising immunotherapy target and may provide additional treatment strategies.

Xiao Y, Deng WW, Yang LL, et al.
Overexpression of p21-activated kinase 2 is correlated with high-grade oral squamous cell carcinomas.
Future Oncol. 2018; 14(11):1091-1100 [PubMed] Related Publications
AIM: p21-activated kinase 2 (PAK2) is overexpressed in several tumors but the expression of PAK2 in oral squamous cell carcinomas (OSCCs) remains unclear.
MATERIALS & METHODS: Immunohistochemistry was performed on human tissue microarrays containing 165 primary OSCC, 48 oral epithelial dysplasia and 43 normal oral mucosa.
RESULTS: PAK2 expression was increased in primary OSCC compared with normal mucosa and significantly increased in primary OSCC grade III compared with grade I, but independent of overall survival rate. Moreover, the expression of PAK2 was statistically correlated with Lck/Yes novel tyrosine kinase (LYN), zinc finger transcription factor Slug, tumor-associated macrophage marker CD163 and LAG3.
CONCLUSION: Overexpression of PAK2 in OSCC may be associated with an advanced pathology grade.

Janikowska G, Janikowski T, Pyka-Pająk A, et al.
Potential biomarkers for the early diagnosis of colorectal adenocarcinoma - transcriptomic analysis of four clinical stages.
Cancer Biomark. 2018; 22(1):89-99 [PubMed] Related Publications
BACKGROUNDS: Colorectal cancer is the third most common cancer in economically developed countries. Molecular studies and, in particular, gene expression have contributed to advances in the diagnosis and treatment of many cancers. Genes can be molecular and therapeutic markers, but because of the large molecular diversity in colorectal cancer the knowledge is not yet fully established. Probably one of the most crucial processes during early cancer development is inflammation. The inflammatory response in the tumor is an important indicator of molecular etiology and later of cancer progression.
OBJECTIVE: The aim of this work is to identify potential biomarkers for early stage of colorectal adenocarcinoma in patients' bowel tissues using transcriptomic analysis.
METHODS: Expression of the inflammatory response genes of colorectal cancer at all clinical stages (I-IV) and control of the bowel were evaluated by oligonucleotide microarrays.
RESULTS: Based on statistical analysis many differentially expressed genes were selected. LCK (LCK Proto-Oncogene, Src Family Tyrosine Kinase), GNLY (granulysin), SLC6A6 (Solute-Carrier Family 6 Member 6) and LAMP2 (Lysosomal Associated Membrane Protein 2) were specific for the early stage of the disease. These genes had the properties of the good biomarkers.
CONCLUSIONS: The expression of LCK, GNLY, SLC6A6 and LAMP2 genes could be valuable potential diagnostic biomarkers of the early stage of colorectal adenocarcinoma.

Cui P, Zhang Y, Cui M, et al.
Leukemia cells impair normal hematopoiesis and induce functionally loss of hematopoietic stem cells through immune cells and inflammation.
Leuk Res. 2018; 65:49-54 [PubMed] Related Publications
Bone marrow (BM) failure is often seen in leukemia patients, indicating an abnormal hematopoietic process. However, hematopoiesis in leukemic milieus is largely unknown. In the present study, we utilized one of the most frequent leukemogenic translocations MLL-AF9 to induce leukemia and investigated the hematopoiesis and the activity of hematopoietic stem and progenitor cells (HSPCs) in a leukemic milieu. We found that the phenotypes of the non-leukemic population in leukemic BM were drastically different than normal BM, including blockage of differentiation and a drastically reduced Lin-/Sca+/c-kit+ (LSK) population that contains all HSPCs in leukemic BM. Further, transplantation assays demonstrated that stem cell function of HSPCs from leukemic BM was significantly compromised. Intriguingly, BM from a patient-derived xenograft leukemia model and from immunocompromised mice transplanted with murine MLL-AF9 cells, showed comparable percentage of hematopoietic stem cells (HSCs) to normal controls, indicating that an immunocompetent microenvironment is critical for leukemia-induced loss of HSPCs. Mechanistically, we found that the non-leukemic cells from leukemic BM possessed a more inflammatory profile than either leukemic cells or normal BM counterparts. Co-culturing or co-transplantation with non-leukemic cells from leukemic BM impaired the stem cell function of normal HSPCs in vitro and in vivo respectively, suggesting that the highly inflammatory non-leukemic population in leukemic BM not only is functionally abnormal but displayed a 'leukemia-like' characteristic. Finally, we tested the effect of the anti-inflammation drug diclofenac on leukemia mice. However, no phenotypic changes of HSPCs were observed upon diclofenac treatment due to only mild repression of inflammatory genes by diclofenac, further indicating that inflammation is a powerful negative regulator of HSPCs. Together, our results suggest that leukemia impairs normal hematopoiesis and inflammation as well as immune cells play a critical role in leukemia-induced BM failure.

Till KJ, Allen JC, Talab F, et al.
Lck is a relevant target in chronic lymphocytic leukaemia cells whose expression variance is unrelated to disease outcome.
Sci Rep. 2017; 7(1):16784 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
Pathogenesis of chronic lymphocytic leukaemia (CLL) is contingent upon antigen receptor (BCR) expressed by malignant cells of this disease. Studies on somatic hypermutation of the antigen binding region, receptor expression levels and signal capacity have all linked BCR on CLL cells to disease prognosis. Our previous work showed that the src-family kinase Lck is a targetable mediator of BCR signalling in CLL cells, and that variance in Lck expression associated with ability of BCR to induce signal upon engagement. This latter finding makes Lck similar to ZAP70, another T-cell kinase whose aberrant expression in CLL cells also associates with BCR signalling capacity, but also different because ZAP70 is not easily pharmacologically targetable. Here we describe a robust method of measuring Lck expression in CLL cells using flow cytometry. However, unlike ZAP70 whose expression in CLL cells predicts prognosis, we find Lck expression and disease outcome in CLL are unrelated despite observations that its inhibition produces effects that biologically resemble the egress phenotype taken on by CLL cells treated with idelalisib. Taken together, our findings provide insight into the pathobiology of CLL to suggest a more complex relationship between expression of molecules within the BCR signalling pathway and disease outcome.

Serafin V, Capuzzo G, Milani G, et al.
Glucocorticoid resistance is reverted by LCK inhibition in pediatric T-cell acute lymphoblastic leukemia.
Blood. 2017; 130(25):2750-2761 [PubMed] Related Publications
Pediatric T-acute lymphoblastic leukemia (T-ALL) patients often display resistance to glucocorticoid (GC) treatment. These patients, classified as prednisone poor responders (PPR), have poorer outcome than do the other pediatric T-ALL patients receiving a high-risk adapted therapy. Because glucocorticoids are administered to ALL patients during all the different phases of therapy, GC resistance represents an important challenge to improving the outcome for these patients. Mechanisms underlying resistance are not yet fully unraveled; thus our research focused on the identification of deregulated signaling pathways to point out new targeted approaches. We first identified, by reverse-phase protein arrays, the lymphocyte cell-specific protein-tyrosine kinase (LCK) as aberrantly activated in PPR patients. We showed that LCK inhibitors, such as dasatinib, bosutinib, nintedanib, and WH-4-023, are able to induce cell death in GC-resistant T-ALL cells, and remarkably, cotreatment with dexamethasone is able to reverse GC resistance, even at therapeutic drug concentrations. This was confirmed by specific

Siriboonpiputtana T, Zeisig BB, Zarowiecki M, et al.
Transcriptional memory of cells of origin overrides β-catenin requirement of MLL cancer stem cells.
EMBO J. 2017; 36(21):3139-3155 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
While β-catenin has been demonstrated as an essential molecule and therapeutic target for various cancer stem cells (CSCs) including those driven by MLL fusions, here we show that transcriptional memory from cells of origin predicts AML patient survival and allows β-catenin-independent transformation in MLL-CSCs derived from hematopoietic stem cell (HSC)-enriched LSK population but not myeloid-granulocyte progenitors. Mechanistically, β-catenin regulates expression of downstream targets of a key transcriptional memory gene,

Märklin M, Heitmann JS, Fuchs AR, et al.
NFAT2 is a critical regulator of the anergic phenotype in chronic lymphocytic leukaemia.
Nat Commun. 2017; 8(1):755 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
Chronic lymphocytic leukaemia (CLL) is a clonal disorder of mature B cells. Most patients are characterised by an indolent disease course and an anergic phenotype of their leukaemia cells, which refers to a state of unresponsiveness to B cell receptor stimulation. Up to 10% of CLL patients transform from an indolent subtype to an aggressive form of B cell lymphoma over time (Richter´s syndrome) and show a significantly worse treatment outcome. Here we show that B cell-specific ablation of Nfat2 leads to the loss of the anergic phenotype culminating in a significantly compromised life expectancy and transformation to aggressive disease. We further define a gene expression signature of anergic CLL cells consisting of several NFAT2-dependent genes including Cbl-b, Grail, Egr2 and Lck. In summary, this study identifies NFAT2 as a crucial regulator of the anergic phenotype in CLL.NFAT2 is a transcription factor that has been linked with chronic lymphocytic leukaemia (CLL), but its functions in CLL manifestation are still unclear. Here the authors show, by analysing mouse CLL models and characterising biopsies from CLL patients, that NFAT2 is an important regulator for the anergic phenotype of CLL.

Clarke CN, Lee MS, Wei W, et al.
Proteomic Features of Colorectal Cancer Identify Tumor Subtypes Independent of Oncogenic Mutations and Independently Predict Relapse-Free Survival.
Ann Surg Oncol. 2017; 24(13):4051-4058 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
BACKGROUND: The directed study of the functional proteome in colorectal cancer (CRC) has identified critical protein markers and signaling pathways; however, the prognostic relevance of many of these proteins remains unclear.
METHODS: We determined the prognostic implications of the functional proteome in 263 CRC tumor samples from patients treated at MD Anderson Cancer Center (MDACC) and 462 patients from The Cancer Genome Atlas (TCGA) to identify patterns of protein expression that drive tumorigenesis. A total of 163 validated proteins were analyzed by reverse phase protein array (RPPA). Unsupervised hierarchical clustering of the tumor proteins from the MDACC cohort was performed, and clustering was validated using RPPA data from TCGA CRC. Cox regression was used to identify predictors of tumor recurrence.
RESULTS: Clustering revealed dichotomization, with subtype A notable for a high epithelial-mesenchymal transition (EMT) protein signature, while subtype B was notable for high Akt/TSC/mTOR pathway components. Survival data were only available for the MDACC cohort and were used to evaluate prognostic relevance of these protein signatures. Group B demonstrated worse relapse-free survival (hazard ratio 2.11, 95% confidence interval 1.04-4.27, p = 0.039), although there was no difference in known genomic drivers between the two proteomic groups. Proteomic grouping and stage were significant predictors of recurrence on multivariate analysis. Eight proteins were found to be significant predictors of tumor recurrence on multivariate analysis: Collagen VI, FOXO3a, INPP4B, LcK, phospho-PEA15, phospho-PRAS40, Rad51, phospho-S6.
CONCLUSION: CRC can be classified into distinct subtypes by proteomic features independent of common oncogenic driver mutations. Proteomic analysis has identified key biomarkers with prognostic importance, however these findings require further validation in an independent cohort.

Frey AB
The Inhibitory Signaling Receptor Protocadherin-18 Regulates Tumor-Infiltrating CD8
Cancer Immunol Res. 2017; 5(10):920-928 [PubMed] Related Publications
Cancers are infiltrated with antitumor CD8

Glass JL, Hassane D, Wouters BJ, et al.
Epigenetic Identity in AML Depends on Disruption of Nonpromoter Regulatory Elements and Is Affected by Antagonistic Effects of Mutations in Epigenetic Modifiers.
Cancer Discov. 2017; 7(8):868-883 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
We performed cytosine methylation sequencing on genetically diverse patients with acute myeloid leukemia (AML) and found leukemic DNA methylation patterning is primarily driven by nonpromoter regulatory elements and CpG shores. Enhancers displayed stronger differential methylation than promoters, consisting predominantly of hypomethylation. AMLs with dominant hypermethylation featured greater epigenetic disruption of promoters, whereas those with dominant hypomethylation displayed greater disruption of distal and intronic regions. Mutations in

Tan Y, Sementino E, Xu J, et al.
The homeoprotein Dlx5 drives murine T-cell lymphomagenesis by directly transactivating Notch and upregulating Akt signaling.
Oncotarget. 2017; 8(9):14941-14956 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
Homeobox genes play a critical role in embryonic development, but they have also been implicated in cancer through mechanisms that are largely unknown. While not expressed during normal T-cell development, homeobox transcription factor genes can be reactivated via recurrent chromosomal rearrangements in human T-cell acute leukemia/lymphoma (T-ALL), a malignancy often associated with activated Notch and Akt signaling. To address how epigenetic reprogramming via an activated homeobox gene might contribute to T-lymphomagenesis, we investigated a transgenic mouse model with thymocyte-specific overexpression of the Dlx5 homeobox gene. We demonstrate for the first time that Dlx5 induces T-cell lymphomas with high penetrance. Integrated ChIP-seq and mRNA microarray analyses identified Notch1/3 and Irs2 as direct transcriptional targets of Dlx5, a gene signature unique to lymphomas from Lck-Dlx5 mice as compared to T-cell lymphomas from Lck-MyrAkt2 mice, which were previously reported by our group. Moreover, promoter/enhancer studies confirmed that Dlx5 directly transactivates Notch expression. Notch1/3 expression and Irs2-induced Akt signaling were upregulated throughout early stages of T-cell development, which promoted cell survival during β-selection of T lymphocytes. Dlx5 was required for tumor maintenance via its activation of Notch and Akt, as tumor cells were highly sensitive to Notch and Akt inhibitors. Together, these findings provide unbiased genetic and mechanistic evidence that Dlx5 acts as an oncogene when aberrantly expressed in T cells, and that it is a novel discovery that Notch is a direct target of Dlx5. These experimental findings provide mechanistic insights about how reactivation of the Dlx5 gene can drive T-ALL by aberrant epigenetic reprogramming of the T-cell genome.

Amengual JE, Prabhu SA, Lombardo M, et al.
Mechanisms of Acquired Drug Resistance to the HDAC6 Selective Inhibitor Ricolinostat Reveals Rational Drug-Drug Combination with Ibrutinib.
Clin Cancer Res. 2017; 23(12):3084-3096 [PubMed] Article available free on PMC after 01/10/2019 Related Publications

Duque-Afonso J, Lin CH, Han K, et al.
E2A-PBX1 Remodels Oncogenic Signaling Networks in B-cell Precursor Acute Lymphoid Leukemia.
Cancer Res. 2016; 76(23):6937-6949 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
There is limited understanding of how signaling pathways are altered by oncogenic fusion transcription factors that drive leukemogenesis. To address this, we interrogated activated signaling pathways in a comparative analysis of mouse and human leukemias expressing the fusion protein E2A-PBX1, which is present in 5%-7% of pediatric and 50% of pre-B-cell receptor (preBCR

Dezorella N, Katz BZ, Shapiro M, et al.
SLP76 integrates into the B-cell receptor signaling cascade in chronic lymphocytic leukemia cells and is associated with an aggressive disease course.
Haematologica. 2016; 101(12):1553-1562 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
I In the last decade, the B-cell receptor has emerged as a pivotal stimulus in the pathogenesis of chronic lymphocytic leukemia, and a very feasible therapeutic target in this disease. B-cell receptor responsiveness in chronic lymphocytic leukemia cells is heterogeneous among patients and correlates with aggressiveness of the disease. Here we show, for the first time, that SLP76, a key scaffold protein in T-cell receptor signaling, is ectopically expressed in chronic lymphocytic leukemia cells, with variable levels among patients, and correlates positively with unmutated immunoglobulin heavy chain variable gene status and ZAP-70 expression. We found that SLP76 was functionally active in chronic lymphocytic leukemia cells. A SYK-dependent basal level of phosphorylated SLP76 exists in the cells, and upon B-cell receptor engagement, SLP76 tyrosine phosphorylation is significantly enhanced concomitantly with increased physical association with BTK. B-cell receptor-induced SLP76 phosphorylation is mediated by upstream signaling events involving LCK and SYK. Knockdown of SLP76 in the cells resulted in decreased induction of BTK, PLCγ2 and IκB phosphorylation, as well as cell viability after B-cell receptor activation with anti-IgM. Consistent with our biochemical findings, high total SLP76 expression in chronic lymphocytic leukemia cells correlated with a more aggressive disease course.
IN CONCLUSION: SLP76 is ectopically expressed in chronic lymphocytic leukemia cells where it plays a role in B-cell receptor signaling.

Iglesia MD, Parker JS, Hoadley KA, et al.
Genomic Analysis of Immune Cell Infiltrates Across 11 Tumor Types.
J Natl Cancer Inst. 2016; 108(11) [PubMed] Article available free on PMC after 01/10/2019 Related Publications
BACKGROUND: Immune infiltration of the tumor microenvironment has been associated with improved survival for some patients with solid tumors. The precise makeup and prognostic relevance of immune infiltrates across a broad spectrum of tumors remain unclear.
METHODS: Using mRNA sequencing data from The Cancer Genome Atlas (TCGA) from 11 tumor types representing 3485 tumors, we evaluated lymphocyte and macrophage gene expression by tissue type and by genomic subtypes defined within and across tumor tissue of origin (Cox proportional hazards, Pearson correlation). We investigated clonal diversity of B-cell infiltrates through calculating B-cell receptor (BCR) repertoire sequence diversity. All statistical tests were two-sided.
RESULTS: High expression of T-cell and B-cell signatures predicted improved overall survival across many tumor types including breast, lung, and melanoma (breast CD8_T_Cells hazard ratio [HR] = 0.36, 95% confidence interval [CI] = 0.16 to 0.81, P = .01; lung adenocarcinoma B_Cell_60gene HR = 0.71, 95% CI = 0.58 to 0.87, P = 7.80E-04; melanoma LCK HR = 0.86, 95% CI = 0.79 to 0.94, P = 6.75E-04). Macrophage signatures predicted worse survival in GBM, as did B-cell signatures in renal tumors (Glioblastoma Multiforme [GBM]: macrophages HR = 1.62, 95% CI = 1.17 to 2.26, P = .004; renal: B_Cell_60gene HR = 1.17, 95% CI = 1.04 to 1.32, P = .009). BCR diversity was associated with survival beyond gene segment expression in melanoma (HR = 2.67, 95% CI = 1.32 to 5.40, P = .02) and renal cell carcinoma (HR = 0.36, 95% CI = 0.15 to 0.87, P = .006).
CONCLUSIONS: These data support existing studies suggesting that in diverse tissue types, heterogeneous immune infiltrates are present and typically portend an improved prognosis. In some tumor types, BCR diversity was also associated with survival. Quantitative genomic signatures of immune cells warrant further testing as prognostic markers and potential biomarkers of response to cancer immunotherapy.

Browning RL, Byrd WH, Gupta N, et al.
Lenalidomide Induces Interleukin-21 Production by T Cells and Enhances IL21-Mediated Cytotoxicity in Chronic Lymphocytic Leukemia B Cells.
Cancer Immunol Res. 2016; 4(8):698-707 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
The immunomodulatory drug lenalidomide has demonstrated efficacy in patients with chronic lymphocytic leukemia (CLL), despite a lack of direct cytotoxic effects in vitro The mechanism of lenalidomide efficacy in vivo is thought to occur via a combination of enhanced immune activity and an alteration of tumor cell-microenvironment interactions. We demonstrate in whole blood from patients with CLL that lenalidomide significantly depletes malignant B cells. Lenalidomide also induced production of interleukin-21 (IL21) and its mRNA in T cells from patients with CLL. In addition, lenalidomide enhanced upregulation of functional IL21 receptor (IL21R) on the cell surface and increased receptor mRNA in vitro The in vitro combination of IL21 and lenalidomide enhanced IL21-mediated cytotoxicity toward CLL cells through a variety of mechanisms. We show association of cell death with upregulation of Bid by IL21, enhanced upregulation of Bid by the combination therapy, and diminished Lck and downstream BCR signaling activation of Syk and PLCG2. Collectively, we demonstrated an immune cell-tumor cell interaction through lenalidomide-mediated induction of IL21 and IL21R, with enhanced IL21-mediated cytotoxicity, which provides justification for this combination in clinical trials for patients with CLL. Cancer Immunol Res; 4(8); 698-707. ©2016 AACR.

Li J, Bi L, Shi Z, et al.
RNA-Seq analysis of non-small cell lung cancer in female never-smokers reveals candidate cancer-associated long non-coding RNAs.
Pathol Res Pract. 2016; 212(6):549-54 [PubMed] Related Publications
We aimed to elucidate the potential mechanisms of long non-coding RNAs (lncRNAs) in the progression of non-small cell lung cancer (NSCLC). The microarray datasets of GSE37764, including 3 primary NSCLC tumors and 3 matched normal tissues isolated from 6 Korean female never-smokers, were downloaded from Gene Expression Omnibus database. The differentially expressed lncRNAs and mRNA in NSCLC samples were identified using NOISeq package. Co-expression network of differentially expressed lncRNAs and mRNA was established. Gene Ontology (GO) and pathway enrichment analysis were respectively performed. Finally, lncRNAs related to NSCLC were predicted by blasting the differentially expressed lncRNAs with all predicted lncRNAs related to NSCLC. A total of 182 and 539 differentially expressed lncRNAs and mRNA (109 up- and 73 down-regulated lncRNAs; 307 up- and 232 down-regulated mRNA) were respectively identified. Among them, 4 up-regulated lncRNAs, like lnc-geranylgeranyl diphosphate synthase 1 (GGPS1), lnc-zinc finger protein 793 (ZNF793) and lnc-serine/threonine kinase 4 (STK4), and 4 down-regulated lncRNAs including lnc-LOC284440 and lnc-peptidylprolyl isomerase E-like pseudogene (PPIEL), and lnc-zinc finger protein 461 (ZNF461) were predicted related to NSCLC. lncSSPS1, lnc-ZNF793 and lnc-STK4 were co-expressed with linker for activation of T cells (LAT) and Lck interacting transmembrane adaptor 1 (LIME1). Lnc-LOC284440, lnc-PPIEL and lnc-ZNF461 were co-expressed with Src-like-adaptor 2 (SLA2) and defensin beta 4A (DEFB4A). Our study indicates that immune response may be a crucial mechanism involved in NSCLC progression. Lnc-GGPS1, lnc-ZNF793, lnc-STK4, lnc-LOC284440, lnc-PPIEL, and lnc-ZNF461 may be involved in immune response for promoting NSCLC progression via co-expressing with LAT, LIME1, SLA2 and DEFB4A.

Kristensen LS, Michaelsen SR, Dyrbye H, et al.
Assessment of Quantitative and Allelic MGMT Methylation Patterns as a Prognostic Marker in Glioblastoma.
J Neuropathol Exp Neurol. 2016; 75(3):246-55 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
Methylation of the O(6)-methylguanine-DNA methyltransferase (MGMT) gene is a predictive and prognostic marker in newly diagnosed glioblastoma patients treated with temozolomide but how MGMT methylation should be assessed to ensure optimal detection accuracy is debated. We developed a novel quantitative methylation-specific PCR (qMSP) MGMT assay capable of providing allelic methylation data and analyzed 151 glioblastomas from patients receiving standard of care treatment (Stupp protocol). The samples were also analyzed by immunohistochemistry (IHC), standard bisulfite pyrosequencing, and genotyped for the rs1690252 MGMT promoter single nucleotide polymorphism. Monoallelic methylation was observed more frequently than biallelic methylation, and some cases with monoallelic methylation expressed the MGMT protein whereas others did not. The presence of MGMT methylation was associated with better overall survival (p = 0.006; qMSP and p = 0.002; standard pyrosequencing), and the presence of the protein was associated with worse overall survival (p = 0.009). Combined analyses of qMSP and standard pyrosequencing or IHC identified additional patients who benefited from temozolomide treatment. Finally, low methylation levels were also associated with better overall survival (p = 0.061; qMSP and p = 0.02; standard pyrosequencing). These data support the use of both MGMT methylation and MGMT IHC but not allelic methylation data as prognostic markers in patients with temozolomide-treated glioblastoma.

Wu T, Wang X, Li J, et al.
Identification of Personalized Chemoresistance Genes in Subtypes of Basal-Like Breast Cancer Based on Functional Differences Using Pathway Analysis.
PLoS One. 2015; 10(6):e0131183 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
Breast cancer is a highly heterogeneous disease that is clinically classified into several subtypes. Among these subtypes, basal-like breast cancer largely overlaps with triple-negative breast cancer (TNBC), and these two groups are generally studied together as a single entity. Differences in the molecular makeup of breast cancers can result in different treatment strategies and prognoses for patients with different breast cancer subtypes. Compared with other subtypes, basal-like and other ER+ breast cancer subtypes exhibit marked differences in etiologic factors, clinical characteristics and therapeutic potential. Anthracycline drugs are typically used as the first-line clinical treatment for basal-like breast cancer subtypes. However, certain patients develop drug resistance following chemotherapy, which can lead to disease relapse and death. Even among patients with basal-like breast cancer, there can be significant molecular differences, and it is difficult to identify specific drug resistance proteins in any given patient using conventional variance testing methods. Therefore, we designed a new method for identifying drug resistance genes. Subgroups, personalized biomarkers, and therapy targets were identified using cluster analysis of differentially expressed genes. We found that basal-like breast cancer could be further divided into at least four distinct subgroups, including two groups at risk for drug resistance and two groups characterized by sensitivity to pharmacotherapy. Based on functional differences among these subgroups, we identified nine biomarkers related to drug resistance: SYK, LCK, GAB2, PAWR, PPARG, MDFI, ZAP70, CIITA and ACTA1. Finally, based on the deviation scores of the examined pathways, 16 pathways were shown to exhibit varying degrees of abnormality in the various subgroups, indicating that patients with different subtypes of basal-like breast cancer can be characterized by differences in the functional status of these pathways. Therefore, these nine differentially expressed genes and their associated functional pathways should provide the basis for novel personalized clinical treatments of basal-like breast cancer.


Genomic Classification of Cutaneous Melanoma.
Cell. 2015; 161(7):1681-96 [PubMed] Article available free on PMC after 01/10/2019 Related Publications
We describe the landscape of genomic alterations in cutaneous melanomas through DNA, RNA, and protein-based analysis of 333 primary and/or metastatic melanomas from 331 patients. We establish a framework for genomic classification into one of four subtypes based on the pattern of the most prevalent significantly mutated genes: mutant BRAF, mutant RAS, mutant NF1, and Triple-WT (wild-type). Integrative analysis reveals enrichment of KIT mutations and focal amplifications and complex structural rearrangements as a feature of the Triple-WT subtype. We found no significant outcome correlation with genomic classification, but samples assigned a transcriptomic subclass enriched for immune gene expression associated with lymphocyte infiltrate on pathology review and high LCK protein expression, a T cell marker, were associated with improved patient survival. This clinicopathological and multi-dimensional analysis suggests that the prognosis of melanoma patients with regional metastases is influenced by tumor stroma immunobiology, offering insights to further personalize therapeutic decision-making.

Chen YC, Chang YC, Ke WC, Chiu HW
Cancer adjuvant chemotherapy strategic classification by artificial neural network with gene expression data: An example for non-small cell lung cancer.
J Biomed Inform. 2015; 56:1-7 [PubMed] Related Publications
PURPOSE: Adjuvant chemotherapy (ACT) is used after surgery to prevent recurrence or metastases. However, ACT for non-small cell lung cancer (NSCLC) is still controversial. This study aimed to develop prediction models to distinguish who is suitable for ACT (ACT-benefit) and who should avoid ACT (ACT-futile) in NSCLC.
METHODS: We identified the ACT correlated gene signatures and performed several types of ANN algorithms to construct the optimal ANN architecture for ACT benefit classification. Reliability was assessed by cross-data set validation.
RESULTS: We obtained 2 probes (2 genes) with T-stage clinical data combination can get good prediction result. These genes included 208893_s_at (DUSP6) and 204891_s_at (LCK). The 10-fold cross validation classification accuracy was 65.71%. The best result of ANN models is MLP14-8-2 with logistic activation function.
CONCLUSIONS: Using gene signature profiles to predict ACT benefit in NSCLC is feasible. The key to this analysis was identifying the pertinent genes and classification. This study maybe helps reduce the ineffective medical practices to avoid the waste of medical resources.

Disclaimer: This site is for educational purposes only; it can not be used in diagnosis or treatment.

Cite this page: Cotterill SJ. LCK, Cancer Genetics Web: http://www.cancer-genetics.org/LCK.htm Accessed:

Creative Commons License
This page in Cancer Genetics Web by Simon Cotterill is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Note: content of abstracts copyright of respective publishers - seek permission where appropriate.

 [Home]    Page last revised: 01 September, 2019     Cancer Genetics Web, Established 1999