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Evidence suggests that ETV6/RUNX1 translocation in pediatric acute lymphocytic leukemia shows geographical variation. Therefore, the present study aimed at unveiling the incidence of ETV6/RUNX1 fusion in pediatric acute lymphocytic leukemia cases of this region using fluorescent in-situ hybridization. Besides, we aimed to determine the incidence of MLL gene rearrangement and the pattern of chromosomal abnormalities in this study group.Samples from 57 acute lymphocytic leukemia cases of pediatric age group were subjected to fluorescent in-situ hybridization and conventional cytogenetic analysis using standard methods.Conventional cytogenetic analysis revealed chromosomal abnormalities in 19.3% cases. The other major chromosomal abnormalities reported were monosomies in 10.5%, hypodiploidy in 7%, marker chromosomes in 3.5% and deletions in 3.5% cases. We found a 44,XX,-7,-18, r(5), i(17q) complex karyotype in one of the cases. Fluorescent in-situ hybridization analysis revealed ETV6/RUNX1 translocation to be present in 28.07% cases and MLL gene rearrangement in 3.5% cases. 12.5% of ETV6/RUNX1 fusion positive cases were found to have a loss of ETV6 allele. Besides, 8.8% cases were found to exhibit a signal pattern suggestive of RUNX1 amplification. ETV6 gene deletion and MLL gene amplification was detected in 3.5% cases each, of our study.Frequency of ETV6/RUNX1 fusion oncogene was found to be higher in pediatric ALL cases of Kashmir region as compared to that reported from other parts of India. Besides, a case was found to have a karyotype viz 44,XX,-7,-18, r(5), i(17q) that has not been reported elsewhere in the childhood ALL.

We have previously shown the involvement of p66shc in mediating apoptosis. Here, we demonstrate the novel mechanism of β-Amyloid-induced toxicity in the mammalian cells. β-Amyloid leads to the phosphorylation of p66shc at the serine 36 residue and activates MKK6, by mediating the phosphorylation at serine 207 residue. Treatment of cells with antioxidants blocks β-Amyloid-induced serine phosphorylation of MKK6, reactive oxygen species (ROS) generation, and hence protected cells against β-Amyloid-induced cell death. Our results indicate that serine phosphorylation of p66shc is carried out by active MKK6. MKK6 knock-down resulted in decreased serine 36 phosphorylation of p66shc. Co-immunoprecipitation results demonstrate a direct physical association between p66shc and WT MKK6, but not with its mutants. Increase in β-Amyloid-induced ROS production was observed in the presence of MKK6 and p66shc, when compared to triple mutant of MKK6 (inactive) and S36 mutant of p66shc. ROS scavengers and knock-down against p66shc, and MKK6 significantly decreased the endogenous level of active p66shc, ROS production, and cell death. Finally, we show that the MKK6-p66shc complex mediates β-Amyloid-evoked apoptotic cell death.

The expression of E3B1/ABI-1 protein and its role in cancer progression and prognosis are largely unknown in the majority of solid tumors. In this study, we examined the expression pattern of E3B1/ABI-1 protein in histologically confirmed cases of esophageal (squamous cell carcinoma and adenocarcinoma), gastro-esophageal junction, colorectal cancers and corresponding normal tissues freshly resected from a cohort of 135 patients, by Western Blotting and Immunofluorescence Staining. The protein is present in its phosphorylated form in cells and tissues. Depending on the extent of phosphorylation it is either present in hyper-phosphorylated (M. Wt. 72 kDa) form or in hypo-phosphorylated form (M. Wt. 68 kDa and 65 kDa). A thorough analysis revealed that expression of E3B1/ABI-1 protein is significantly decreased in esophageal, gastro-esophageal junction and colorectal carcinomas irrespective of age, gender, dietary and smoking habits of the patients. The decrease in expression of E3B1/ABI-1 was consistently observed for all the three isoforms. However, the decrease in the expression of isoforms varied with different forms of cancers. Down-regulation of E3B1/ABI-1 expression in human carcinomas may play a critical role in tumor progression and in determining disease prognosis.

We studied the expression of α1-syntrophin (SNTA1) protein in histologically confirmed esophageal, stomach, lung, colon, rectal and breast cancerous tissue samples. Our results suggest a significant decrease in the expression level of SNTA1 protein in both esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) compared with their respective controls while a significant increase in expression of SNTA1 protein compared with the normal tissue was observed in breast carcinoma samples. No significant difference in expression of SNTA1 protein was observed in stomach, lung, colon and rectal cancers. Our results suggest that SNTA1 has a role in carcinogenesis and could possibly be used as a novel diagnostic or prognostic marker in esophageal and breast cancers.

Expression analysis of MKK6 protein in solid tumors has never been investigated. Here, we report systematic analysis of MKK6 protein in different types of human tumor samples using western blotting and immunofluorescence techniques. We observed significant increase in the expression of MKK6 in Esophageal, Stomach, and Colon cancers as compared to controls. Results were alternately confirmed by Immunofluorescence studies. Upregulation of MKK6 protein is indicative of its role in human cancers and could possibly be used as a novel diagnostic or prognostic marker in these cancers.

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.

Members of Shc (src homology and collagen homology) family, p46shc, p52shc, p66shc have known to be related to cell proliferation and carcinogenesis. Whereas p46shc and p52shc drive the reaction forward, the role of p66shc in cancers remains to be understood clearly. Hence, their expression in cancers needs to be evaluated carefully so that Shc analysis may provide prognostic information in the development of carcinogenesis. In the present study, the expression of p66shc and its associate targets namely Eps8 (epidermal pathway substrate 8), Rac1 (ras-related C3 botulinum toxin substrate1) and Grb2 (growth factor receptor bound protein 2) were examined in fresh tissue specimens from patients with esophageal squamous cell carcinoma and esophageal adenocarcinoma using western blot analysis. A thorough analysis of both esophageal squamous cell carcinoma and adenocarcinoma showed p66shc expression to be significantly higher in both types of carcinomas as compared to the controls. The controls of adenocarcinoma show a higher basal expression level of p66shc as compared to the controls of squamous cell carcinoma. The expression level of downstream targets of p66shc i.e., eps8 and rac1 was also found to be consistently higher in human esophageal carcinomas, and hence correlated positively with p66shc expression. However the expression of grb2 was found to be equal in both esophageal squamous cell carcinoma and adenocarcinoma. The above results suggest that the pathway operated by p66shc in cancers does not involve the participation of Ras and Grb2 as downstream targets instead it operates the pathway involving Eps8 and Rac1 proteins. From the results it is also suggestive that p66shc may have a role in the regulation of esophageal carcinomas and represents a possible mechanism of signaling for the development of squamous cell carcinoma and adenocarcinoma of esophagus.