Does hormone therapy, tibolone or raloxifene modify VEGF expression in cervical epithelial cells?

Vascular endothelial growth factor (VEGF) seems to be a critical molecule in cervical carcinogenesis. We aimed to investigate the possible associations between hormonal factors and VEGF expression in cervical epithelial cells from postmenopausal women.

A total of 105 healthy postmenopausal women (aged 45-68 years old) attending a university menopause clinic were enrolled in this cross-sectional study. Pap smears were derived from current users of 17β-estradiol 1 mg + norethisterone acetate 0.5 mg (n = 28), tibolone 2.5 mg (n = 23), raloxifene HCl 60 mg (n = 21) and women not receiving treatment (n = 33). VEGF immunostaining was evaluated in squamous, glandular and metaplastic cells, using a semiquantitative method (rating scale: 0-3).

Concerning endogenous hormones, higher Δ4-androstenedione levels were associated with more intense VEGF immunostaining in glandular (p = 0.041) and metaplastic cells (p = 0.004). Hormone therapy and raloxifene did not induce any changes in VEGF immunoreactivity in the examined cells. In contrast, tibolone administration was accompanied by diminished VEGF presence in metaplastic cells (p = 0.016 vs. controls).

Our findings may in part reflect the molecular processes contributing to the safe profile of hormone therapy, tibolone and raloxifene in cervical carcinogenesis.