In the United States, lung cancer is the second most common cancer in men and women. In 2017, 222,500 new cases and 155,870 deaths from lung cancer are estimated to have occurred. A tyrosine kinase receptor, epidermal growth factor receptor (EGFR), is over expressed or mutated in non-small cell lung cancer (NSCLC) resulting in increased cell proliferation and survival. Tyrosine kinase inhibitors (TKIs) are currently being used as therapy for NSCLC patients, however, they have limited efficacy in NSCLC patients due to acquisition of resistance. This study investigates the role of epithelial-mesenchymal transition (EMT) in the development of resistance against TKIs in NSCLC. Currently, the role of p120-catenin, Kaiso factor and PRMT-1 in reversal of EMT in T790M mutated and TKI-resistant NSCLC cells is a new line of study. In this investigation we found upregulation of cytoplasmic p120-catenin, which was co-localized with Kaiso factor. In the nucleus, binding of p120-catenin to Kaiso factor initiates transcription by activating EMT-transcription factors such as Snail, Slug, Twist, and ZEB1. PRMT-1 was also found to be upregulated, which induces methylation of Twist and repression of E-cadherin activity, thus promoting EMT. We confirmed that TKI-resistant cells have mesenchymal cell type characteristics based on their cell morphology and gene or protein expression of EMT related proteins. EMT proteins, Vimentin and N-cadherin, displayed increased expression, whereas E-cadherin expression was downregulated. Finally, we found that the knockdown of p120-catenin and PRMT-1 by siRNA or use of a PRMT-1 inhibitor Furamidine increased Erlotinib sensitivity and could reverse EMT to overcome TKI resistance.
The vast majority of EVAR were successfully performed under RA, involved mild blood loss, involved infrequent need for conversion to GA, and resulted in brief in-hospital length of stay and low mortality rate.
Background: EGFR/c-Met activation/amplification and co-expression, mTOR upregulation/activation, and Akt/Wnt signaling upregulation have been individually associated with more aggressive disease and characterized as potential prognostic markers for lung cancer patients. Methods: Tumors obtained from 109 participants with stage I–IV non-small cell lung cancer (NSCLC) were studied for EGFR/c-Met co-localization as well as for total and active forms of EGFR, c-Met, mTOR, S6K, beta-catenin, and Axin2. Slides were graded by two independent blinded pathologists using a validated scoring system. Protein expression profile correlations were assessed using Pearson correlation and Spearman’s rho. Prognosis was assessed using Kaplan–Meier analysis. Results: Protein expression profile analysis revealed significant correlations between EGFR/p-EGFR ( p = 0.0412) and p-mTOR/S6K ( p = 0.0044). Co-localization of p-EGFR/p-c-Met was associated with increased p-mTOR ( p = 0.0006), S6K ( p = 0.0018), and p-S6K ( p < 0.0001) expression. In contrast, active beta-catenin was not positively correlated with EGFR/c-Met nor any activated proteins. Axin2, a negative regulator of the Wnt pathway, was correlated with EGFR, p-EGFR, p-mTOR, p-S6K, EGFR/c-Met co-localization, and p-EGFR/p-c-Met co-localization (all p-values <0.03). Kaplan–Meier analysis revealed shorter median survival in participants with high expression of Axin2, total beta-catenin, total/p-S6K, total/p-mTOR, EGFR, and EGFR/c-Met co-localization compared with low expression. After controlling for stage of disease at diagnosis, subjects with late-stage disease demonstrated shorter median survival when exhibiting high co-expression of EGFR/c-Met (8.1 month versus 22.3 month, p = 0.050), mTOR (6.7 month versus 22.3 month, p = 0.002), and p-mTOR (8.1 month versus 25.4 month, p = 0.004) compared with low levels. Conclusions: These findings suggest that increased EGFR/c-Met signaling is correlated with upregulated mTOR/S6K signaling, which may in turn be associated with shorter median survival in late-stage NSCLC.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.