Research IndicatorsGraph generated 17 August 2015 using data from PubMed using criteria.
Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic. Tag cloud generated 17 August, 2015 using data from PubMed, MeSH and CancerIndex
Specific Cancers (3)
Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.
Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).
OMIM, Johns Hopkin University
Referenced article focusing on the relationship between phenotype and genotype.
International Cancer Genome Consortium.
Summary of gene and mutations by cancer type from ICGC
Cancer Genome Anatomy Project, NCI
COSMIC, Sanger Institute
Somatic mutation information and related details
Search the Epigenomics database and view relevant gene tracks of samples.
Latest Publications: SHC1 (cancer-related)
Tumor cell migration is a key process for cancer cell dissemination and metastasis that is controlled by signal-mediated cytoskeletal and cell matrix adhesion remodeling. Using a phagokinetic track assay with migratory H1299 cells, we performed an siRNA screen of almost 1,500 genes encoding kinases/phosphatases and adhesome- and migration-related proteins to identify genes that affect tumor cell migration speed and persistence. Thirty candidate genes that altered cell migration were validated in live tumor cell migration assays. Eight were associated with metastasis-free survival in breast cancer patients, with integrin β3-binding protein (ITGB3BP), MAP3K8, NIMA-related kinase (NEK2), and SHC-transforming protein 1 (SHC1) being the most predictive. Examination of genes that modulate migration indicated that SRPK1, encoding the splicing factor kinase SRSF protein kinase 1, is relevant to breast cancer outcomes, as it was highly expressed in basal breast cancer. Furthermore, high SRPK1 expression correlated with poor breast cancer disease outcome and preferential metastasis to the lungs and brain. In 2 independent murine models of breast tumor metastasis, stable shRNA-based SRPK1 knockdown suppressed metastasis to distant organs, including lung, liver, and spleen, and inhibited focal adhesion reorganization. Our study provides comprehensive information on the molecular determinants of tumor cell migration and suggests that SRPK1 has potential as a drug target for limiting breast cancer metastasis.
Huang C, Sheng Y, Jia J, Chen LIdentification of melanoma biomarkers based on network modules by integrating the human signaling network with microarrays.
J Cancer Res Ther. 2014; 10 Suppl:C114-24 [PubMed
] Related Publications
BACKGROUND: Melanoma is a leading cause of cancer death. Thus, accurate prognostic biomarkers that will assist rational treatment planning need to be identified.
METHODS: Microarray analysis of melanoma and normal tissue samples was performed to identify differentially expressed modules (DEMs) from the signaling network and ultimately detect molecular markers to support histological examination. Network motifs were extracted from the human signaling network. Then, significant expression-correlation differential modules were identified by comparing the network module expression-correlation differential scores under normal and disease conditions using the gene expression datasets. Finally, we obtained DEMs by the Wilcoxon rank test and considered the average gene expression level in these modules as the classification features for diagnosing melanoma.
RESULTS: In total, 99 functional DEMs were identified from the signaling network and gene expression profiles. The area under the curve scores for cancer module genes, melanoma module genes, and whole network modules are 92.4%, 90.44%, and 88.45%, respectively. The classification efficiency rates for nonmodule features are 71.04% and 79.38%, which correspond to the features of cancer genes and melanoma cancer genes, respectively. Finally, we acquired six significant molecular biomarkers, namely, module 10 (CALM3, Ca 2+ , PKC, PDGFRA, phospholipase-g, PIB5PA, and phosphatidylinositol-3-kinase), module 14 (SRC, Src homology 2 domain-containing [SHC], SAM68, GIT1, transcription factor-4, CBLB, GRB2, VAV2, LCK, YES, PTCH2, downstream of tyrosine kinase [DOK], and KIT), module 16 (ELK3, p85beta, SHC, ZFYVE9, TGFBR1, TGFBR2, CITED1, SH3KBP1, HCK, DOK, and KIT), module 45 (RB, CCND3, CCNA2, CDK4, and CDK6), module 75 (PCNA, CDK4, and CCND1), and module 114 (PSD93, NMDAR, and FYN).
CONCLUSION: We explored the gene expression profile and signaling network in a global view and identified DEMs that can be used as diagnostic or prognostic markers for melanoma.
Wei WJ, Lu ZW, Li DS, et al.Association of the miR-149 Rs2292832 polymorphism with papillary thyroid cancer risk and clinicopathologic characteristics in a Chinese population.
Int J Mol Sci. 2014; 15(11):20968-81 [PubMed
] Free Access to Full Article Related Publications
(1) BACKGROUND: The genetic predisposition to papillary thyroid cancer (PTC) is far from clearly elucidated. Rs2292832 is a genetic polymorphism that located in the precursor of mir-149 and has been studied in diverse cancers. Thus far, the role of rs2292832 in PTC tumorigenesis and progression was unclear; (2) METHOD: Rs2292832 was genotyped in 838 PTCs, 495 patients with thyroid benign tumors (BNs) and 1006 controls in a Chinese Han population. Clinicopathological data was collected and compared. The expression level of mature mir-149 was examined in 55 normal thyroid tissue samples; (3) RESULTS: The CC genotype of rs2292832 was significantly associated with an increased risk of PTC compared with TT homozygote (OR = 1.60, 95% CI: 1.72-2.20, p = 0.003) and TT/TC combined genotype (OR = 1.54, 95% CI: 1.14-2.09, p = 0.005). Rs2292832 is an independent risk factor correlated with tumor invasion (p = 0.006) and higher T stage in PTC patients (p = 0.007), but uncorrelated with short-term disease persistence of PTC. PTC subjects carrying CC genotype have lower mir-149-5p expression than those with TC genotype (p = 0.002). Twelve predicted target genes have been identified by collaboratively using computational tools; (4) CONCLUSION: Rs2292832 was possibly involved in the susceptibility and local progression of PTC in Chinese patients, by altering the expression level of mir-149-5p and its target genes.
ERBB3/HER3 is emerging as a molecular target for various cancers. HER3 is overexpressed and activated in a number of cancer types under the conditions of acquired resistance to other HER family therapeutic interventions such as tyrosine kinase inhibitors and antibody therapies. Regulation of the HER3 expression and signaling involves numerous HER3 interacting proteins. These proteins include PI3K, Shc, and E3 ubiquitin ligases NEDD4 and Nrdp1. Furthermore, recent identification of a number of HER3 oncogenic mutations in colon and gastric cancers elucidate the role of HER3 in cancer development. Despite the strong evidence regarding the role of HER3 in cancer, the current understanding of the regulation of HER3 expression and activation requires additional research. Moreover, the lack of biomarkers for HER3-driven cancer poses a big challenge for the clinical development of HER3 targeting antibodies. Therefore, a better understanding of HER3 regulation should improve the strategies to therapeutically target HER3 for cancer therapy.
Gao S, Bajrami I, Verrill C, et al.Dsh homolog DVL3 mediates resistance to IGFIR inhibition by regulating IGF-RAS signaling.
Cancer Res. 2014; 74(20):5866-77 [PubMed
] Related Publications
Drugs that inhibit insulin-like growth factor 1 (IGFI) receptor IGFIR were encouraging in early trials, but predictive biomarkers were lacking and the drugs provided insufficient benefit in unselected patients. In this study, we used genetic screening and downstream validation to identify the WNT pathway element DVL3 as a mediator of resistance to IGFIR inhibition. Sensitivity to IGFIR inhibition was enhanced specifically in vitro and in vivo by genetic or pharmacologic blockade of DVL3. In breast and prostate cancer cells, sensitization tracked with enhanced MEK-ERK activation and relied upon MEK activity and DVL3 expression. Mechanistic investigations showed that DVL3 is present in an adaptor complex that links IGFIR to RAS, which includes Shc, growth factor receptor-bound-2 (Grb2), son-of-sevenless (SOS), and the tumor suppressor DAB2. Dual DVL and DAB2 blockade synergized in activating ERKs and sensitizing cells to IGFIR inhibition, suggesting a nonredundant role for DVL3 in the Shc-Grb2-SOS complex. Clinically, tumors that responded to IGFIR inhibition contained relatively lower levels of DVL3 protein than resistant tumors, and DVL3 levels in tumors correlated inversely with progression-free survival in patients treated with IGFIR antibodies. Because IGFIR does not contain activating mutations analogous to EGFR variants associated with response to EGFR inhibitors, we suggest that IGF signaling achieves an equivalent integration at the postreceptor level through adaptor protein complexes, influencing cellular dependence on the IGF axis and identifying a patient population with potential to benefit from IGFIR inhibition.
Breast cancers are stratified into distinct subtypes, which influence therapeutic responsiveness and patient outcome. Patients with luminal breast cancers are often associated with a better prognosis relative to that with other subtypes. However, subsets of patients with luminal disease remain at increased risk of cancer-related death. A critical process that increases the malignant potential of breast cancers is the epithelial-to-mesenchymal transition (EMT). The p66ShcA adaptor protein stimulates the formation of reactive oxygen species in response to stress stimuli. In this paper, we report a novel role for p66ShcA in inducing an EMT in HER2(+) luminal breast cancers. p66ShcA increases the migratory properties of breast cancer cells and enhances signaling downstream of the Met receptor tyrosine kinase in these tumors. Moreover, Met activation is required for a p66ShcA-induced EMT in luminal breast cancer cells. Finally, elevated p66ShcA levels are associated with the acquisition of an EMT in primary breast cancers spanning all molecular subtypes, including luminal tumors. This is of high clinical relevance, as the luminal and HER2 subtypes together comprise 80% of all newly diagnosed breast cancers. This study identifies p66ShcA as one of the first prognostic biomarkers for the identification of more aggressive tumors with mesenchymal properties, regardless of molecular subtype.
Anchorage of tissue cells to their physical environment is an obligate requirement for survival that is lost in mature hematopoietic and in transformed epithelial cells. Here we find that a lymphocyte lineage-restricted transcription factor, Aiolos, is frequently expressed in lung cancers and predicts markedly reduced patient survival. Aiolos decreases expression of a large set of adhesion-related genes, disrupting cell-cell and cell-matrix interactions. Aiolos also reconfigures chromatin structure within the SHC1 gene, causing isoform-specific silencing of the anchorage reporter p66(Shc) and blocking anoikis in vitro and in vivo. In lung cancer tissues and single cells, p66(Shc) expression inversely correlates with that of Aiolos. Together, these findings suggest that Aiolos functions as an epigenetic driver of lymphocyte mimicry in metastatic epithelial cancers.
In this issue of Cancer Cell, Li and colleagues demonstrate that the hematopoietic transcription factor Aiolos (named after the Wind God of Greek mythology) confers anoikis resistance in lung tumor cells through repression of cell adhesion-related genes including the mechanosensor p66Shc.
Pomerleau V, Landry M, Bernier J, et al.Met receptor-induced Grb2 or Shc signals both promote transformation of intestinal epithelial cells, albeit they are required for distinct oncogenic functions.
BMC Cancer. 2014; 14:240 [PubMed
] Free Access to Full Article Related Publications
BACKGROUND: Deregulation of receptor tyrosine kinases (RTK) contributes to the initiation and progression of intestinal-derived epithelial cancers, including colorectal cancer (CRC). However, the roles of the proximal signaling molecules engaged by RTKs in different oncogenic functions of CRC remain unclear.
METHODS: Herein, the functional impact of expressing variant forms of the oncogenic Met receptor (Tpr-Met) that selectively recruit the adaptor proteins Grb2 or Shc was investigated in a model derived from normal intestinal epithelial cells (IEC-6). An RNA interference (RNAi) approach was used to define the requirement of Grb2 or Shc in Tpr-Met-transformed IEC-6 cells. Since Grb2 and Shc couple RTKs to the activation of the Ras/MEK/Erk and PI3K/Akt pathways, Erk and Akt phosphorylation/activation states were monitored in transformed IEC-6 cells, and a pharmacological approach was employed to provide insights into the roles of these pathways in oncogenic processes evoked by activated Met, and downstream of Grb2 and Shc.
RESULTS: We show, for the first time, that constitutive activation of either Grb2 or Shc signals in IEC-6 cells, promotes morphological transformation associated with down-regulation of E-cadherin, as well as increased cell growth, loss of growth contact inhibition, anchorage-independent growth, and resistance to serum deprivation and anoikis. Oncogenic activation of Met was revealed to induce morphological transformation, E-cadherin down-regulation, and protection against anoikis by mechanisms dependent on Grb2, while Shc was shown to be partly required for enhanced cell growth. The coupling of activated Met to the Ras/MEK/Erk and PI3K/Akt pathways, and the sustained engagement of Grb2 or Shc in IECs, was shown to trigger negative feedback, limiting the extent of activation of these pathways. Nonetheless, morphological alterations and E-cadherin down-regulation induced by the oncogenic Tpr-Met, and by Grb2 or Shc signals, were blocked by MEK, but not PI3K, inhibitors while the enhanced growth and resistance to anoikis induced by Tpr-Met were nearly abolished by co-treatment with both inhibitors.
CONCLUSION: Overall, these results identify Grb2 and Shc as central signaling effectors of Met-driven progression of intestinal epithelial-derived cancers. Notably, they suggest that Grb2 may represent a promising target for the design of novel CRC therapies.
BACKGROUND: Alpha-1-syntrophin (SNTA1) has been implicated in the activation of Rac1. However, the underlying mechanism has not yet been explored. Here, we show that a novel complex, involving SNTA1, P66shc, and Grb2 proteins, is involved in Rac1 activation.
METHODS: Co-immunoprecipitation assays were used to show the complex formation, while siRNAs and shRNAs were used to downregulate expression of these proteins. Various Rac1 activation assays and functional assays, such as migration assays, in vitro wound healing assays, cell proliferation assays, and ROS generation assays, were also performed.
RESULTS: The results showed a significant increase in activation of Rac1 when SNTA1 and P66shc were overexpressed, whereas depletion of SNTA1 and P66shc expression effectively reduced the levels of active Rac1. The results indicated a significant displacement of Sos1 protein from Grb2 when SNTA1 and P66shc are overexpressed in breast cancer cell lines, resulting in Sos1 predominantly forming a complex with Eps8 and E3b1. In addition, the SNTA1/P66shc-mediated Rac1 activation resulted in an increase in reactive oxygen species (ROS) production and migratory potential in human breast cancer cells.
CONCLUSION: Together, our results present a possible mechanism of Rac1 activation involving SNTA1 and emphasise its role in ROS generation, cell migration, and acquisition of malignancy.
Proto-oncogenic Src homology and collagen (Shc) proteins have been considered archetypal adaptors of epidermal growth factor receptor (EGFR)-mediated signaling. We report that in addition to its role as an EGFR-binding partner and Grb2 platform, ShcD acts noncanonically to promote phosphorylation of select EGFR residues. Unexpectedly, Y1068, Y1148, and Y1173 are subject to ShcD-induced, cell-autonomous hyperphosphorylation in the absence of external stimuli. This response is not elicited by other Shc proteins and requires the intrinsic EGFR kinase, as well as the ShcD phosphotyrosine-binding (PTB) domain. Assessments of Erk, Akt, phospholipase C 1γ, and FAK pathways reveal no apparent distal signaling targets of ShcD. Nevertheless, the capacity of cultured cells to repopulate a wounded monolayer is markedly accelerated by ShcD in an EGFR kinase-dependent manner. Furthermore, detection of overexpressed ShcD coincident with EGFR phosphorylation in human gliomas suggests a clinical application for these findings. We thus demonstrate unique and relevant synergy between ShcD and EGFR that is unprecedented among signaling adaptors.
Sarajlić A, Filipović A, Janjić V, et al.The role of genes co-amplified with nicastrin in breast invasive carcinoma.
Breast Cancer Res Treat. 2014; 143(2):393-401 [PubMed
] Related Publications
Breast cancer accounts for more than 450,000 deaths per year worldwide. Discovery of novel therapeutic targets that will allow patient-tailored treatment of this disease is an emerging area of scientific interest. Recently, nicastrin has been identified as one such therapeutic target. Its overexpression is indicative of worse overall survival in the estrogen-receptor-negative patient population. In this paper, we analyze data from a large invasive breast carcinoma study and confirm nicastrin amplification. In search for genes that are co-amplified with nicastrin, we identify a potential novel breast cancer-related amplicon located on chromosome 1. Furthermore, we search for "influential interactors," i.e., genes that interact with a statistically significantly high number of genes which are co-amplified with nicastrin, and confirm their involvement in this female neoplasm. Among the influential interactors, we find genes which belong to the core diseasome (a recently identified therapeutically relevant set of genes which is known to drive disease formation) and propose that they might be important for breast cancer onset, and serve as its novel therapeutic targets. Finally, we identify a pathway that may play a role in nicastrin's amplification process and we experimentally confirm downstream signaling mechanism of nicastrin in breast cancer cells.
Tao HC, Wang HX, Dai M, et al.Targeting SHCBP1 inhibits cell proliferation in human hepatocellular carcinoma cells.
Asian Pac J Cancer Prev. 2013; 14(10):5645-50 [PubMed
] Related Publications
Src homology 2 domain containing (SHC) is a proto-oncogene which mediates cell proliferation and carcinogenesis in human carcinomas. Here, the SHC SH2-domain binding protein 1 (SHCBP1) was first established to be up-regulated in human hepatocellular carcinoma (HCC) tissues by array-base comparative genome hybridization (aCGH). Meanwhile, we examine and verify it by quantitative real-time PCR and western blot. Our current data show that SHCBP1 was up-regulated in HCC tissues. Overexpression of SHCBP1 could significantly promote HCC cell proliferation, survival and colony formation in HCC cell lines. Furthermore, knockdown of SHCBP1 induced cell cycle delay and suppressed cell proliferation. Furthermore, SHCBP1 could regulate the expression of activate extracellular signal-regulated kinase 1/2 (ERK1/2) and cyclin D1. Together, our findings indicate that SHCBP1 may contribute to human hepatocellular carcinoma by promoting cell proliferation and may serve as a molecular target of cancer therapy.
Hamada S, Masamune A, Miura S, et al.MiR-365 induces gemcitabine resistance in pancreatic cancer cells by targeting the adaptor protein SHC1 and pro-apoptotic regulator BAX.
Cell Signal. 2014; 26(2):179-85 [PubMed
] Related Publications
The poor prognosis of invasive ductal adenocarcinoma of the pancreas is mainly due to its resistance against therapeutic agents. The molecular mechanism by which morbidity enhances cell survival has been extensively studied, but radical improvements in the therapeutic strategy have not yet been achieved. Recent reports have indicated the substantial contribution of miRNA in multiple cell functions by comprehensively targeting clusters of genes. We identified several miRNAs highly expressed in invasive ductal adenocarcinoma in our previous study, and clarified their contribution to the epithelial-mesenchymal transition. Among the differentially expressed miRNAs, miR-365 was highly expressed in invasive ductal adenocarcinoma, whose functional role has not been reported. In the current study, we found that miR-365 induced gemcitabine resistance in pancreatic cancer cells. MiR-365 directly targeted adaptor protein Src Homology 2 Domain Containing 1 (SHC1) and apoptosis-promoting protein BAX. The siRNA-based knockdown of SHC1 and BAX increased gemcitabine resistance, indicating the miR-365/SHC1/BAX axis influences the survival of pancreatic cancer cells. In addition, miR-365 up-regulated cancer-promoting molecules such as Inhibitor of DNA binding 2 and S100P, suggesting the existence of cross-talk with other cancer-promoting signals. MiR-365 could exert orchestrated effects on pancreatic cancer cell survival.
Liu Y, Song H, Pan J, Zhao JComprehensive gene expression analysis reveals multiple signal pathways associated with prostate cancer.
J Appl Genet. 2014; 55(1):117-24 [PubMed
] Related Publications
Prostate cancer (PC) depends on androgenic signaling for growth and survival. To data, the exact molecular mechanism of hormone controlling proliferation and tumorigenesis in the PC remains unclear. Therefore, in this study, we explored the differentially expressed genes (DEGs) and identified featured genes related to hormone stimulus from PC. Two sets of gene expression data, including PC and normal control sample, were downloaded from Gene Expression Omnibus (GEO) database. The t-test was used to identify DEGs between PC and controls. Gene ontology (GO) functional annotation was applied to analyze the function of DEGs and screen hormone-related DEGs. Then these hormone-related DEGs were further analyzed in constructed cancer network and Human Protein Reference Database to screen important signaling pathways they participated in. A total of 912 DEGs were obtained which included 326 up-regulated genes and 586 down-regulated genes. GO functional enrichment analysis identified 50 hormone-related DEGs associated with PC. After pathway and PPI network analysis, we found these hormone-related DEGs participated in several important signaling pathways including TGF-β (TGFB2, TGFB3 and TGFBR2), MAPK (TGFB2, TGFB3 and TGFBR2), insulin (PIK3R3, SHC1 and EIF4EBP1), and p53 signaling pathways (CCND2 and CDKN1A). In addition, a total of five hormone-related DEGs (SHC1, CAV1, RXRA, CDKN1A and SRF) were located in the center of PPI network and 12 hormone-related DEGs formed six protein modules. These important signal pathways and hormone-related DEGs may provide potential therapeutic targets for PC.
Browne BC, Hochgräfe F, Wu J, et al.Global characterization of signalling networks associated with tamoxifen resistance in breast cancer.
FEBS J. 2013; 280(21):5237-57 [PubMed
] Related Publications
Acquired resistance to the anti-estrogen tamoxifen remains a significant challenge in breast cancer management. In this study, we used an integrative approach to characterize global protein expression and tyrosine phosphorylation events in tamoxifen-resistant MCF7 breast cancer cells (TamR) compared with parental controls. Quantitative mass spectrometry and computational approaches were combined to identify perturbed signalling networks, and candidate regulatory proteins were functionally interrogated by siRNA-mediated knockdown. Network analysis revealed that cellular metabolism was perturbed in TamR cells, together with pathways enriched for proteins associated with growth factor, cell-cell and cell matrix-initiated signalling. Consistent with known roles for Ras/MAPK and PI3-kinase signalling in tamoxifen resistance, tyrosine-phosphorylated MAPK1, SHC1 and PIK3R2 were elevated in TamR cells. Phosphorylation of the tyrosine kinase Yes and expression of the actin-binding protein myristoylated alanine-rich C-kinase substrate (MARCKS) were increased two- and eightfold in TamR cells respectively, and these proteins were selected for further analysis. Knockdown of either protein in TamR cells had no effect on anti-estrogen sensitivity, but significantly decreased cell motility. MARCKS expression was significantly higher in breast cancer cell lines than normal mammary epithelial cells and in ER-negative versus ER-positive breast cancer cell lines. In primary breast cancers, cytoplasmic MARCKS staining was significantly higher in basal-like and HER2 cancers than in luminal cancers, and was independently predictive of poor survival in multivariate analyses of the whole cohort (P < 0.0001) and in ER-positive patients (P = 0.0005). These findings provide network-level insights into the molecular alterations associated with the tamoxifen-resistant phenotype, and identify MARCKS as a potential biomarker of therapeutic responsiveness that may assist in stratification of patients for optimal therapy.
Zheng Z, Yang J, Zhao D, et al.Downregulated adaptor protein p66(Shc) mitigates autophagy process by low nutrient and enhances apoptotic resistance in human lung adenocarcinoma A549 cells.
FEBS J. 2013; 280(18):4522-30 [PubMed
] Related Publications
Macroautophagy or autophagy is a lysosome-dependent process in which enzymatic degradation and recycling of cytosolic components occur in stressful contexts. The mechanisms underlying the signaling from starvation to the regulation of autophagy are not fully understood. We previously showed that the Src family member p66(Shc) (focal adhesion-associated 66 kDa isoform of the Src homology and collagen) promotes anoikis and suppresses tumor metastasis via k-Ras-dependent control of proliferation and survival. However, the role of p66(Shc) in low-nutrient-induced autophagy-related pathways remains elusive. In this work, human lung adenocarcinoma A549 cells were used to further investigate the biological effects of p66(Shc) on autophagy and apoptotic resistance. Here, we show that deficiency of p66(Shc) mitigates the low-nutrient-induced autophagy process in the levels of microtubule-associated protein 1A light chain protein 3B (LC3B) conversion, in the number of autophagic vacuoles and in p62/sequestosome 1 protein degradation. However, autophagy-related protein Beclin 1 was not significantly changed during low-nutrient treatment. Furthermore, we found that prolonged phosphorylation of extracellular signaling-regulated kinase (Erk)1/2, but not phosphorylation of Akt is significantly sustained when p66(Shc) expression is inhibited by shRNA. In addition, cleavage of caspase 7 and poly(ADP-ribose) polymerase, but not caspase 6 and 9 are retarded with this effect compared to the shRNA control cells. Together, these findings suggest the possibility that p66(Shc) plays a pivotal role in coordinately regulating autophagy process and apoptotic resistance in A549 cells under nutrient-limited conditions.
Ahn R, Sabourin V, Ha JR, et al.The ShcA PTB domain functions as a biological sensor of phosphotyrosine signaling during breast cancer progression.
Cancer Res. 2013; 73(14):4521-32 [PubMed
] Related Publications
ShcA (SHC1) is an adapter protein that possesses an SH2 and a PTB phosphotyrosine-binding motif. ShcA generally uses its PTB domain to engage activated receptor tyrosine kinases (RTK), but there has not been a definitive determination of the role of this domain in tumorigenesis. To address this question, we employed a ShcA mutant (R175Q) that no longer binds phosphotyrosine residues via its PTB domain. Here, we report that transgenic expression of this mutant delays onset of mammary tumors in the MMTV-PyMT mouse model of breast cancer. Paradoxically, we observed a robust increase in the growth and angiogenesis of mammary tumors expressing ShcR175Q, which displayed increased secretion of fibronectin and expression of integrin α5/β1, the principal fibronectin receptor. Sustained integrin engagement activated Src, which in turn phosphorylated proangiogenic RTKs, including platelet-derived growth factor receptor, fibroblast growth factor receptor, and Met, leading to increased VEGF secretion from ShcR175Q-expressing breast cancer cells. We defined a ShcR175Q-dependent gene signature that could stratify breast cancer patients with a high microvessel density. This study offers the first in vivo evidence of a critical role for intracellular signaling pathways downstream of the ShcA PTB domain, which both positively and negatively regulate tumorigenesis during various stages of breast cancer progression.
Du W, Jiang Y, Zheng Z, et al.Feedback loop between p66(Shc) and Nrf2 promotes lung cancer progression.
Cancer Lett. 2013; 337(1):58-65 [PubMed
] Related Publications
p66(Shc), one of the SHC1 gene encoding proteins, promotes cell death and reports cell anchorage status, mediating anoikis in vitro and functioning as a metastasis suppressor in vivo. However, very little is known about p66(Shc) gene regulation in cancer cells. Here, we show that methylation of a specific CpG site in the early post-transcriptional region correlates with p66(Shc) repression in clinical human lung cancer samples and cancer cell lines. We also find that the stress related transcription factor Nrf2 associates with p66(Shc) gene promoter in the methylated region, and promotes p66(Shc) transcription. However, p66(Shc) induction by Nrf2 requires demethylation of the Nrf2 binding site in p66(Shc) promoter. Knock-down of p66(Shc) leads to a positive feedback upregulation of Nrf2 expression and accordingly, Nrf2 is found to be highly expressed in tumors with low p66(Shc) expression. Further, Nrf2 expression level positively correlates with tumor grade of patients. Thus, we propose that epigenetic repression of p66(Shc) in cancer cells might be a key factor leading to Nrf2 upregulation, increased cell survival, and tumor progression.
Gillis LC, Berry DM, Minden MD, et al.Gads (Grb2-related adaptor downstream of Shc) is required for BCR-ABL-mediated lymphoid leukemia.
Leukemia. 2013; 27(8):1666-76 [PubMed
] Related Publications
Philadelphia chromosome-positive leukemias, including chronic myeloid leukemia and B-cell acute lymphoblastic leukemia (B-ALL), are driven by the oncogenic BCR-ABL fusion protein. Animal modeling experiments utilizing retroviral transduction and subsequent bone marrow transplantation have demonstrated that BCR-ABL generates both myeloid and lymphoid disease in mice receiving whole bone marrow transduced with BCR-ABL. Y177 of BCR-ABL is critical to the development of myeloid disease, and phosphorylation of Y177 has been shown to induce GRB2 binding to BCR-ABL, followed by activation of the Ras and phosphoinositide 3 kinase signaling pathways. We show that the GRB2-related adapter protein, GADS, also associates with BCR-ABL, specifically through Y177 and demonstrate that BCR-ABL-driven lymphoid disease requires Gads. BCR-ABL transduction of Gads(-/-) bone marrow results in short latency myeloid disease within 3-4 weeks of transplant, while wild-type mice succumb to both a longer latency lymphoid and myeloid diseases. We report that GADS mediates a unique BCR-ABL complex with SLP-76 in BCR-ABL-positive cell lines and B-ALL patient samples. These data suggest that GADS mediates lymphoid disease downstream of BCR-ABL through the recruitment of specific signaling intermediates.
Protein tyrosine phosphatase (PTP)-proline-, glutamate-, serine-, and threonine-rich sequence (PEST) is ubiquitously expressed and is a critical regulator of cell adhesion and migration. PTP-PEST activity can be regulated transcriptionally via gene deletion or mutation in several types of human cancers or via post-translational modifications, including phosphorylation, oxidation, and caspase-dependent cleavage. PTP-PEST interacts with and dephosphorylates cytoskeletal and focal adhesion-associated proteins. Dephosphorylation of PTP-PEST substrates regulates their enzymatic activities and/or their interaction with other proteins and plays an essential role in the tumor cell migration process.
Overexpression of Shc adaptor proteins is associated with mitogenesis, carcinogenesis and metastasis. Multiple copies in T-cell malignancy 1 (MCT-1) oncoprotein promotes cell proliferation, survival and tumorigenic effects. Our current data show that MCT-1 is a novel regulator of Shc-Ras-MEK-ERK signaling and MCT-1 is significantly co-activated with Shc gene in human carcinomas. The knockdown of MCT-1 enhances apoptotic cell death accompanied with the activation of caspases and cleavage of caspase substrates under environmental stress. The cancer cell proliferation, chemo-resistance and tumorigenic capacity are proved to be effectively suppressed by targeting MCT-1. Accordingly, an important linkage between MCT-1 oncogenicity and Shc pathway in tumor development has now been established. Promoting MCT-1 expression by gene hyperactivation may be recognized as a tumor marker and MCT-1 may serve as a molecular target of cancer therapy.
SnoN/SkiL (TGFβ regulator) is dysregulated in ovarian cancer, a disease associated with acquired drug-resistance. Arsenic trioxide (As₂O₃, used in treating APL) induces SnoN to oppose the apoptotic response in ovarian cancer cells. We now report that As₂O₃ increases phosphorylation of EGFR/p66ShcA and EGFR degradation. As₂O₃ activates Src(Y416) whose activity (inhibited by PP2) modulates EGFR activation, its interaction with Shc/Grb2, and p-AKT. Inhibition of PI3K reduces SnoN and cell survival. Although EGFR or MAPK1 siRNA did not alter SnoN expression, As₂O₃-induced cleaved PARP was reduced together with increased XIAP. Collectively, As₂O₃ mediates an initial rise in pY-Src(416) to regulate the PI3K/AKT pathway which increases SnoN and cell survival; these early events may counter the cell death response associated with increased pY-EGFR/MAPK activation.
Capitani N, Patrussi L, Trentin L, et al.S1P1 expression is controlled by the pro-oxidant activity of p66Shc and is impaired in B-CLL patients with unfavorable prognosis.
Blood. 2012; 120(22):4391-9 [PubMed
] Related Publications
Although intrinsic apoptosis defects are causal to the extended survival of chronic lymphocytic leukemia (CLL) B cells, several lines of evidence support a contribution of the peripheral lymphoid organs and BM microenvironment to the extended lifespan of leukemic B cells. Lymphocyte trafficking is controlled by homing signals provided by stromal cell-derived chemokines and egress signals provided by sphingosine-1-phosphate (S1P). In the present study, we show that expression of S1P1, the S1P receptor responsible for lymphocyte egress, is selectively reduced in CLL B cells with unmutated IGHV. Expression of S1P2, which controls B-cell homeostasis, is also impaired in CLL B cells but independently of the IGHV mutational status. We provide evidence herein that p66Shc, a Shc adaptor family member the deficiency of which is implicated in the apoptosis defects of CLL B cells, controls S1P1 expression through its pro-oxidant activity. p66Shc also controls the expression of the homing receptor CCR7, which opposes S1P1 by promoting lymphocyte retention in peripheral lymphoid organs. The results of the present study provide insights into the regulation of S1P1 expression in B cells and suggest that defective egress caused by impaired S1P1 expression contributes to the extended survival of CLL B cells by prolonging their residency in the prosurvival niche of peripheral lymphoid organs.
Vo DT, Subramaniam D, Remke M, et al.The RNA-binding protein Musashi1 affects medulloblastoma growth via a network of cancer-related genes and is an indicator of poor prognosis.
Am J Pathol. 2012; 181(5):1762-72 [PubMed
] Free Access to Full Article Related Publications
Musashi1 (Msi1) is a highly conserved RNA-binding protein that is required during the development of the nervous system. Msi1 has been characterized as a stem cell marker, controlling the balance between self-renewal and differentiation, and has also been implicated in tumorigenesis, being highly expressed in multiple tumor types. We analyzed Msi1 expression in a large cohort of medulloblastoma samples and found that Msi1 is highly expressed in tumor tissue compared with normal cerebellum. Notably, high Msi1 expression levels proved to be a sign of poor prognosis. Msi1 expression was determined to be particularly high in molecular subgroups 3 and 4 of medulloblastoma. We determined that Msi1 is required for tumorigenesis because inhibition of Msi1 expression by small-interfering RNAs reduced the growth of Daoy medulloblastoma cells in xenografts. To characterize the participation of Msi1 in medulloblastoma, we conducted different high-throughput analyses. Ribonucleoprotein immunoprecipitation followed by microarray analysis (RIP-chip) was used to identify mRNA species preferentially associated with Msi1 protein in Daoy cells. We also used cluster analysis to identify genes with similar or opposite expression patterns to Msi1 in our medulloblastoma cohort. A network study identified RAC1, CTGF, SDCBP, SRC, PRL, and SHC1 as major nodes of an Msi1-associated network. Our results suggest that Msi1 functions as a regulator of multiple processes in medulloblastoma formation and could become an important therapeutic target.
In Caenorhabditis elegans (C. elegans), the promotion of longevity by the transcription factor DAF-16 requires reduced insulin/IGF receptor (IIR) signaling or the ablation of the germline, although the reason for the negative impact of germ cells is unknown. FOXO/DAF-16 activity inhibits germline proliferation in both daf-2 mutants and gld-1 tumors. In contrast to its function as a germline tumor suppressor, we now provide evidence that somatic DAF-16 in the presence of IIR signaling can also result in tumorigenic activity, which counteracts robust lifespan extension. In contrast to the cell-autonomous IIR signaling, which is required for larval germline proliferation, activation of DAF-16 in the hypodermis results in hyperplasia of the germline and disruption of the surrounding basement membrane. SHC-1 adaptor protein and AKT-1 kinase antagonize, whereas AKT-2 and SGK-1 kinases promote, this cell-nonautonomous DAF-16 function. Our data suggest that a functional balance of DAF-16 activities in different tissues determines longevity and reveals a novel, cell-nonautonomous role of FOXO/DAF-16 to affect stem cells.
BACKGROUND: High BCAR4 and ERBB2 mRNA levels in primary breast cancer associate with tamoxifen resistance and poor patient outcome. We determined whether BCAR4 expression sensitises breast cancer cells to lapatinib, and identifies a subgroup of patients who possibly may benefit from ERBB2-targeted therapies despite having tumours with low ERBB2 expression.
METHODS: Proliferation assays were applied to determine the effect of BCAR4 expression on lapatinib treatment. Changes in cell signalling were quantified with reverse-phase protein microarrays. Quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) of ERBB2 and BCAR4 was performed in 1418 primary breast cancers. Combined BCAR4 and ERBB2 mRNA levels were evaluated for association with progression-free survival (PFS) in 293 oestrogen receptor-α (ER)-positive patients receiving tamoxifen as first-line monotherapy for recurrent disease.
RESULTS: BCAR4 expression strongly sensitised ZR-75-1 and MCF7 breast cancer cells to the combination of lapatinib and antioestrogens. Lapatinib interfered with phosphorylation of ERBB2 and its downstream mediators AKT, FAK, SHC, STAT5, and STAT6. Reverse transcriptase-PCR analysis showed that 27.6% of the breast cancers were positive for BCAR4 and 22% expressed also low levels of ERBB2. The clinical significance of combining BCAR4 and ERBB2 mRNA status was underscored by the finding that the group of patients having BCAR4-positive/ERBB2-low-expressing cancers had a shorter PFS on tamoxifen treatment than the BCAR4-negative group.
CONCLUSION: This study shows that BCAR4 expression identifies a subgroup of ER-positive breast cancer patients without overexpression of ERBB2 who have a poor outcome and might benefit from combined ERBB2-targeted and antioestrogen therapy.
Wong J, Garner B, Halliday GM, Kwok JBSrp20 regulates TrkB pre-mRNA splicing to generate TrkB-Shc transcripts with implications for Alzheimer's disease.
J Neurochem. 2012; 123(1):159-71 [PubMed
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Previously, we reported elevated levels of the neuron-specific tropomyosin receptor kinase B (TrkB) transcript, TrkB- sarc homology containing (Shc) in the hippocampus of Alzheimer's disease (AD) brains. In this study, we determined how TrkB-Shc transcripts are increased in AD. Utilizing a TrkB minigene transiently transfected into SHSY5Y cells, we found increased exon 19 inclusion in TrkB minigene transcripts (to generate TrkB-Shc) following cellular exposure to amyloid beta 1-42 (Αβ(42)). As this suggested altered TrkB pre-mRNA splicing in AD, we conducted an in silico screening for putative splice regulatory protein-binding sites in the intron/exon splice regulatory regions of exons 18 and 19 of the TrkB gene and then assessed their gene expression profiles using a microarray database of control/AD post-mortem human hippocampal brain tissue. We found significant changes in serine/arginine protein 20 (Srp20) gene expression in AD cases and confirmed this using a second cohort of control/AD. In vitro, we found increased Srp20 mRNA levels in SHSY5Y cells treated with Αβ(42) fibrils. Moreover, Srp20 over-expression was found to increase exon 19 inclusion in TrkB minigene transcripts and ratio of endogenous TrkB-Shc:TrkB-TK+ mRNA expression. Conversely, Srp20 expression knockdown produced the opposite effects. Our findings suggest that dysregulation of factors regulating TrkB pre-mRNA splicing may contribute to gene expression changes that occur in AD.
Pan Y, Han C, Wang C, et al.ADAM10 promotes pituitary adenoma cell migration by regulating cleavage of CD44 and L1.
J Mol Endocrinol. 2012; 49(1):21-33 [PubMed
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ADAM10 is a metalloproteinase that regulates invasiveness in many tumors. Here, we found that ADAM10 expression correlates with the invasiveness of pituitary adenomas and contributes to invasion by cleaving L1 and CD44. In high-grade pituitary adenoma patients, ADAM10 expression levels were found to be elevated compared with low-grade pituitary adenomas. In a phorbol 12-myristate 13-acetate (PMA)-stimulated pituitary adenoma cell line, AtT-20 cells, we found that the cleavage of L1 was correspondingly enhanced with the increased interaction between Src and Shc. Increases in PMA-induced L1 cleavage and the phosphorylation of residue 418 of Src (418Src) were promoted by overexpression of ADAM10. Inversely, knockdown of Adam10 suppressed PMA-induced L1 cleavage and the phosphorylation of Src, which was blocked by the Src inhibitor PP2 and the MEK inhibitor PD98059. On the other hand, calcium flux activation in AtT-20 cells resulted in increased CD44 cleavage, with reduction of the interaction between calmodulin and ADAM10. The induction of enhanced CD44 cleavage by calcium flux activation was inhibited by knockdown of Adam10. In addition, Adam10 knockdown repressed AtT-20 cell migration, which was reversed by CD44EXT (CD44 ectodomain cleavage). Collectively, these data indicated that ADAM10 facilitated cell migration through modulation of CD44 and L1 cleavage.
Wang Y, Zhu Y, Zhang L, et al.Insulin promotes proliferation, survival, and invasion in endometrial carcinoma by activating the MEK/ERK pathway.
Cancer Lett. 2012; 322(2):223-31 [PubMed
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The involvement of insulin in endometrial carcinoma (EC) was investigated using radioimmunoassay, Western blot, immunoprecipitation, MTT, and Annexin V-FITC/PI assays in tissue samples and cultured cells. Serum levels of insulin, p-p52Shc, p-p46Shc, Shc·Grb2 complexes, p-MEK, p-ERK, and cyclin D1 were elevated in patients with EC. Expression of key proteins in the MEK/ERK pathway, including p-p52Shc, Shc·Grb2 complexes, p-MEK, p-ERK, and cyclin D1, was significantly higher in patients with advanced FIGO stage, high grade, and lymph-node metastasis and correlated positively with serum insulin concentration. Insulin promotes Ishikawa 3-H-12 cell proliferation, survival, and invasion, and these effects induced by insulin were significantly blocked by MEK inhibitor PD98059. Insulin thus promotes EC cell proliferation, survival, and invasion via the MEK/ERK pathway.