Found programs: National Natural Science Foundation of China (No. 82404970); Natural Science Research Project of Anhui Educational Committee (No. 2023AH053170); Clinical Medical Research Translational Project of Anhui Province (No. 202304295107020019).
Authors：Zheng Lin1, Zhong Jianxin2, Niu Ke1, Xu Qing1, Ling Huijuan1, Zhu Yayu1, Chen Bing1,3, Chen Liwen1,4
Keywords：non-small cell lung cancer; cell apoptosis; co-signalling molecules; B7-H3; SIRT1; p53
DOI：专辑：医药卫生科技
〔Abstract〕 To explore the role of the histone deacetylase Sirtuin-1 (SIRT1)/p53 signaling pathway in promoting apoptosis of non-small cell lung cancer cells (NSCLC) induced by the co- stimulatory molecule B7-H3. Methods The GEPIA 2 platform was used for survival analysis of NSCLC patients based on B7-H3 gene expression levels. The Gene Enrichment Analysis (GSEA) method was used to analyze the enrichment characteristics of B7-H3 molecules in the gene set of cell apoptosis. In the non-small cell lung cancer A549 cell line, B7-H3 was knocked down, and the protein expression levels of SIRT1 and p53 were detected by Western blot. B7-H3 was overexpressed in A549 cells and the apoptosis rate was analyzed by flow cytometry after Annexin V/PI double staining. Overexpression of B7-H3 and knockdown ofSIRT1 were performed inA549 cell line. The expression levels of p53 and apoptosis-related proteins B-cell lymphoma/leukemia-2 (Bcl-2) and Bcl-2-associated X protein (Bax) were detected respectively by Western blot. Cell apoptosis rate was analyzed by flow cytometry after Annexin V/PI double staining. Results The overall survival of the B7-H3 high-expression group was significantly lower than that of the low- expression group (P<0.01). B7-H3 was significantly enriched in the cell apoptosis signaling pathway and the p53 signaling pathway (P<0.05). Compared with the control group, the expression of SIRT1 was significantly downregulated, and p53 was significantly upregulated in the B7-H3 knockdown group (both P<0.001). Overexpression of B7-H3 significantly up-regulated SIRT1 protein expression (P<0.05), down-regulated p53 expression (P<0.01), and markedly increased the Bcl-2/Bax ratio of apoptosis-related proteins (P<0.001). The results of Annexin V/PI double staining showed that the apoptosis rate of A549 cells with overexpressed B7-H3 decreased (the apoptosis rate of the control group was 26.72%±4.13%, while that of the B7-H3 overexpression group was 13.87%±0.82%; P<0.01). In B7-H3-overexpressing cell lines, SIRT1 knockdown significantly reversed apoptosis (P<0.05), up-regulated p53 protein expression (P<0.001), and markedly reduced the Bcl-2/Bax ratio (P<0.001). Conclusion B7-H3 molecule inhibits the apoptosis of non-small cell lung cancer cells via the SIRT1/p53 signaling pathway.