Effects of cigarette smoke extract on angiogenesis and aromatase activity in KGN cells

Cigarette smoking is associated with negative reproductive outcomes and an increased likelihood of failed in vitro fertilization. We investigated the impact of cigarette smoke on angiogenesis and aromatase activity in human granulosa cells. The human ovarian granulosa-like tumor cell line (KGN) was exposed to different cigarette smoke extract (CSE) concentrations and/or 10-μM forskolin. mRNA and protein levels and their secretion were measured using real-time polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay techniques, respectively. Additionally, KGN cells were transfected with small interfering RNA (siRNA) targeting hypoxia-inducible factor-1α (HIF-1α) for 24 h, followed by treatment with or without (control) CSE for 48 h. Data were statistically analyzed. Compared with the control group, the CSE group showed significantly increased vascular endothelial growth factor (VEGF), N-myc downstream-regulated gene 1 (NDRG1), and HIF-1α expression. Overexpression of VEGF and NDRG1 induced by CSE was inhibited by HIF-1α siRNA transfection. Furthermore, CSE exposure decreased progesterone and estradiol levels and increased testosterone levels. It also affected the expression of genes associated with steroid hormone synthesis, decreased anti-Müllerian hormone and anti-Müllerian hormone receptor II levels, and caused SMAD signaling pathway desensitization. Thus, CSE adversely affects the maturation of human granulosa cells, affecting both angiogenesis and aromatase activity.