Altered expression of sex hormone receptors in keratoconus corneas

Introduction: Keratoconus is an ectasia that results in corneal thinning in central and paracentral areas of affected corneas. This disease occurs most frequently in young males, underlying a potential role of sex hormones in its pathogenesis. By examining the expression of sex hormone receptors, this study aimed to reveal potential roles of the sex hormone receptors in keratoconus pathogenesis. Methods: Keratoconus and non-keratoconus control corneas were collected from patients volunteered in the West China Hospital. 16 corneas from male patients diagnosed with keratoconus and 9 control corneas from non-keratoconus males were subjected to immunohistochemical staining. The expression of 4 sex hormone receptors, progesterone, androgen and estrogen receptor alpha and estrogen receptor beta was evaluated using their specific antibodies. Results: Compared with the healthy corneas, the progesterone receptor showed significantly lower expression (P=0.01), while androgen receptor expression was significantly higher in keratoconus corneas (p=0.017). No significant difference in estrogen receptor alpha (P=0.978) and estrogen receptor beta (P=0.276) was detected between keratoconus and control corneas. No significant difference in estrogen receptor alpha and estrogen receptor beta was detected between keratoconus and control corneas. Conclusions: The reduction of progesterone receptor expression and increment of androgen receptor expression in keratoconus corneas support that sex hormone receptors are involved in the development of keratoconus.