APOBEC3G inhibits apoptosis and autophagy in cervical intraepithelial neoplasia W12 cells

Cervical intraepithelial neoplasia (CIN) is a collective term for specific precancerous lesions associated with cervical cancer (CC). Given the current poor prognosis, it is imperative to diagnose CIN at an early stage and identify the markers linked to its pathogenesis and prognosis, despite the disease’s documented slow course and numerous levels of cellular alterations. We explored the expression level of the new marker apolipoprotein B mRNA-editing enzyme-catalytic polypeptide-like 3G (APOBEC3G, A3G) and its regulatory effect on CIN. Cell proliferation were assessed using Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2′-deoxyuridine (EdU) staining. Apoptosis rate was detected by flow cytometry. We used immunofluorescence to determine light chain 3B (LC3B) expression. Western blotting was used to detect Bcl2-Associated X (Bax), B-cell lymphoma 2 (Bcl-2), Cleaved caspase-3, p62, LC3-II/LC3-I, transforming growth factor-beta (TGF-β) and decapentaplegic homolog 2 (Smad2) expressions. A3G knockdown significantly inhibited cervical intraepithelial neoplasia cell proliferation, significantly increasing the apoptosis rate and the Bax/Bcl-2 ratio. Also, Cleaved-caspase-3 and LC-II expressions were significantly increased, and p62 expression was decreased. The TGF-β/Smad2 signaling pathway was significantly inhibited. In cervical intraepithelial neoplasia, APOBEC3G inhibits apoptosis and autophagy of W12 cells through TGFβ/Smad2 signaling pathway. In conclusion, we determined that APOBEC3G has a regulatory effect on CIN, which opens a new way to explore its pathogenesis and improve the accuracy of prognosis.

Cervical intraepithelial neoplasia; APOBEC3G; Autophagy; Apoptosis; TGF-β/Smad2

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