Thus AKT may be a switch to determine cell fate as death or survival
Thus AKT may be a switch to determine cell fate as death or survival. NA says for the absence of evidence regarding particular criteria. (PDF 338 kb) 13046_2018_1004_MOESM1_ESM.pdf (338K) GUID:?AB4C670E-B4B6-49CE-B1E0-63EADABBB163 Data Availability StatementNot relevant. Abstract Background Some membrane proteins can translocate into the nucleus, defined as nuclear localized membrane proteins (NLMPs), including receptor tyrosine kinases (RTKs). We previously showed that nuclear MET (nMET), a member of RTKs, mediates malignancy stem-like cells self-renewal to promote cancer recurrence. However, it is unknown that nMET or mMET, which is the ancestor in the development of malignancy cell survival and clearance. Here, we aim to study the NLMP functions in cell death, differentiation and survival. Method We applied the systematic reanalysis of functional NLMP and clinical investigations of nMET from databases. In addition, we used soft agar assay, immunoblotting, circulation cytometry, and immunofluorescence confocal microscopy for examinations of nMET functions including stem-like cell formation, cell signaling, cell cycle regulation, and co-localization with regulators of cell signaling. ShRNA, antibody of realizing surface membrane MET based treatment were used to downregulate endogenous nMET to uncover its function. Results We predicted and exhibited that nMET and nEGFR are most likely not ancestors. nMET overexpression induces both cell death and survival with drug resistance and stem cell-like character types. Moreover, the paradoxical function of nMET in both cell death and cell survival is explained by the fact that nMET induces stem cell-like cell growth, DNA damage repair, to evade the drug sensitization for survival of single cells while non-stem cell-like nMET expressing single cells may undergo clearance by cell death through cell cycle arrest induced by p21. Conclusion Taken together, our data suggest a link between nuclear RTK and malignancy cell evolutionary clearance via cell death, and drug resistance for survival through stemness selection. Targeting developed nuclear RTKs in malignancy stem cells would be a novel avenue for precision malignancy therapy. Electronic supplementary material The online version of this article (10.1186/s13046-018-1004-z) contains supplementary material, which is available to authorized users. gene and cell cycles were analyzed by DNA content. d Nuclear MET overexpression induces cell death and survival proteins in HeLa and HEK293 cells by western blot Next, to further test our hypothesis, we investigated levels of cell death and survival proteins in nMET overexpressed cells. As shown in Fig. ?Fig.5d,5d, nMET overexpressed cells showed higher or lower levels of cleaved Caspase 3, increased DNA A-381393 damage marker H2AX but also increased survival protein Bcl-2, dysregulated p53 and dysregulated cleavage of PARP. The paradoxical dysregulation of cell death and survival may suggest that nMET expressing cells may undergo clearance and survival for cell dynamic transformation. Thus our data suggest that nMET induces both cell death and cell survival signaling. Moreover, cell cycle arrest associated with nMET overexpression may be essential to the dysregulation of the cell death and survival for cells repopulation and development. Nuclear MET drives drug resistance and stemness for cell survival in subsets of cells To understand how nMET might mediate drug resistance, we first tested the effect of Dox on cell survival (Fig. ?(Fig.6a-b).6a-b). We first treated PC3 prostate malignancy cells with the drug for 24 h. As shown in Fig. ?Fig.6a,6a, MET was localized in the nucleus upon drug treatment. Surprisingly, MCF7 breast malignancy cells survived upon treatment with Dox, but Dox became effective when cells were treated with the antibody against MET (Fig. ?(Fig.6b).6b). Thus our A-381393 data suggest that drug resistance may allow clearance of nMET positive cells while survived cells might be nMET overexpressing cells which may have been undergone development. Open in a separate window Fig. 6 Nuclear A-381393 MET mediates stemness and drug resistance. a Nuclear MET expression in PC3 cells upon drug response to doxorubicin (DOX). b Breast SPP1 malignancy MCF7 cells cytotoxicity assay upon treatment with DMSO (control), 60?nM doxorubicin (DOX) alone, antibody (Ab) against MET.