Inhibiting the expression of STARD3 induced apoptosis via the inactivation of PI3K/AKT/mTOR pathway on ER+ breast cancer

Objective: To explore the mechanism of steroidogenic acute regulatory (StAR)-related lipid transfer domain containing 3 (STARD3) in breast cancer (BC). Methods: We analysed the differential mRNA expressions of BC using ER+ and ER-BC expression profiles from the cancer genome atlas (TCGA). Expression and correlation between salient genes was visualized using microarray volcano plots and a protein-protein interaction (PPI) network map. Survival analyses were performed to identify the potential for STARD3 to serve as a prognostic biomarker. The expression of STARD3 was examined by immunohistochemistry (IHC). The effects of STARD3 on apoptosis and proliferation of BC (MCF-7) cell line were deduced by flow cytometry, CCK8, and western blot (WB). Results: STARD3 was the most differentially expressed gene (DEG). Patients in the STARD3 high expression group had significantly lower survival than those in the low expression group. The expression of STARD3 was significantly higher in BC tissues than controls. Inhibiting STARD3 expression significantly increased apoptosis, decreased proliferation, activated PI3K/AKT/mTOR pathway Conclusion: Inhibiting the expression of STARD3 induced apoptosis via the inactivation of PI3K/AKT/mTOR pathway on BC inhibits tumour growth, which can be an effective therapeutic strategy.