Effect of HPV-18 E7 Protein on Proliferation, Apoptosis and Autophagy of Cervical Cancer Cells through SIRT1

This study aimed to investigate the role of HPV-18 E7 protein in proliferation, apoptosis and autophagy of cervical cancer cells infected with HPV through SIRT1. SiRNA targeting HPV-18E7 (E7-siRNA) was used to inhibit the expression of HPV-18 E7. Cell proliferation was detected by CCK-8 assay; cell apoptosis was detected by flow cytometry; the expression of Beclin1 and LC3 were detected by Western blot; the mRNA and protein expression of SIRT1 were detected by qRT-PCR and Western blot. HPV-18 E7 protein was expressed in HaCaT cells with the expression vector, and the expression level of SIRT1 was detected by qRT-PCR and Western blot respectively. Finally, the cells were pretreated with SIRT1 agonist (SRT1720); the cell apoptosis was detected by flow cytometry, and the expression of autophagy-related proteins Beclin1 and LC3 were detected by Western blot. The results showed that after inhibition of HPV-18 E7 expression by E7-siRNA, the cell proliferation and autophagy levels were significantly decreased; the apoptosis level was increased, and the mRNA and protein expression levels of SIRT1 were significantly decreased. HPV-18 E7 was expressed in HaCaT cells, it was found that HPV-18 E7 promoted the expression of SIRT1. SIRT1 agonist treatment can increase the low-level cell proliferation caused by HPV-18 E7 gene silencing, alleviating the apoptosis caused by HPV-18 E7 gene silencing, and increase the expression level of autophagy-related protein Beclin1 and the ratio of LC3-Ⅱ/LC3-Ⅰ. In conclusion, HPV-18 E7 can promote the expression of SIRT1, and then promote the cell proliferation and autophagy, inhibit apoptosis through SIRT1.

CSTR: 32200.14.cjcb.2022.11.0005