Hydrosalpinx fluid diminishes endometrial cell HOXA10 expression.

OBJECTIVE: To determine the effect of hydrosalpinx fluid on the expression of HOXA10, an essential regulator of endometrial receptivity.
DESIGN: In vitro study.
SETTING: Academic medical center. PATIENT(S): Patients with unilateral or bilateral hydrosalpinx. INTERVENTION(S): Hydrosalpinx fluid was aspirated from 10 patients at laparoscopy. The fluid was serially diluted in minimum essential medium. Ishikawa cells (an endometrial adenocarcinoma cell line, representative of endometrial epithelium) were incubated with this fluid at concentrations of 10% and 50% for 48 hours. Cells were also incubated in undiluted minimum essential medium (MEM) and in 10% serum as controls. After incubation, the cells were lysed in Trizol, and total RNA was extracted and analyzed by Northern blot using a 32P-labeled HOXA10 riboprobe. A 32P-labeled G3PDH probe was used as a control for loading. MAIN OUTCOME MEASURE(S): HOXA10 mRNA expression. RESULT(S): HOXA10 mRNA expression in endometrial cells decreased with increasing concentrations of hydrosalpinx fluid. Densitometric analysis of the northern blot revealed that HOXA10 mRNA expression was different from control at both concentrations (P<.007). CONCLUSION(S): HOXA10 is necessary for implantation in the murine model. HOXA10 expression is diminished by hydrosalpinx fluid. This effect on HOXA10 is a potential molecular mechanism by which implantation rates are diminished in women with hydrosalpinges.