Primary study on the signal transduction concerned human papillomavirus 18 E6 oncoprotein / 中华微生物学和免疫学杂志

ABSTRACT

Objective To explore the relationship of signal transduction among human papillomavirus 18 E6 oncoprotein (HPV18E6), signal transducers and activators of transcription 1 (STAT1), protein kinase R( PKR )/α subunit of eukaryotic initiation factor 2 ( eIF2α ), nuclear factor-kappa Bp65 ( NF-κBp65 ), mitogen-activated protein kinase( MAPK)/c-Jun N-terminal kinase(JNK) ,and possible molecular mechanism. Methods Construct two lentiviral vectors which contain shRNA interfering sequence aiming at the targets of HPV18E6 oncogene and NC sequence( HPV18E6-RNAi-LV, NC-GFP-LV), based on the transduction with HPV18E6-RNAi-LV and NC-GFP-LV into HeLa cell to interfere the expression of HPV18E6 oncogene and NC sequence,the expressions of mRNA and protein( including phosphating patem)of HPV18E6, STATI, PKR, eIF2α, NF-κBp65, MAPK, JNK are measured with RT-PCR and Western blot, the difference of proliferation and sensitivity to carboplatin of HeLa cell are determined with Transwell cell methods and MTT among every groups. Results The expression of HPV18E6 oncogene can affect the expression level of mRNA and protein of NF-κBp65 and PKR genes, also affect phosphating levels of phosphating protein p-STAT1, p-PKR and p-eIF2α;the restraining rates of proliferation and sensitivity to carboplatin of HeLa cell are higher in HPV18E6-RNAi-LV group than the other groups( P＜0. 05 or P＜0.01 ). Conclusion HPV18E6 oncoprotein not only reduces the expression of PKR but dephosphorylates p-STAT1, pPKR and p-eIF2α to restrain activation of PKR/eIF2α signal transduction passage, maintain the proliferation and invading ability of HeLa cell and restrain apoptosis. The signal transduction among HPV18E6, MAPK/JNK are not clear.