[Expression of HOXA10 gene in human endometrium and its relationship with unexplained infertility].

Objective: To study the expression of HOXA10 gene in the endometrium of normal fertile women and patients with unexplained infertility during different phases of menstrual cycle.

Methods: Endometrium samples were obtained by curettage in 52 normal fertile women and 38 patients with unexplained infertility during different phases of menstrual cycle, HOXA10 mRNA expression were detected by in situ hybridization and reverse polymerase chain reaction (RT-PCR).

Results: (1) HOXA10 mRNA were detected in the glandular and stromal cells of endometrium of fertile women during the menstrual cycle. By in situ hybridization (positive unite, PU), HOXA10 mRNA levels were significantly higher in the mid-secretory phase [glandular cells (G) 5.69 +/- 0.57, stromal cells (S) 7.48 +/- 0.67] and late-secretory phase(G 5.99 +/- 0.40, S 7.98 +/- 1.08) than those in late proliferative phase (G 3.35 +/- 0.20, S 3.20 +/- 0.37) and early secretory phase (G 3.07 +/- 0.26, S 3.18 +/- 0.27)(P < 0.01). HOXA10 mRNA levels of endometrial stromal cells of mid and late secretory were higher than those of glandular cells (P < 0.01). By RT-PCR, HOXA10 mRNA levels were significantly higher in the mid secretory phase (57.0 +/- 3.4)% and late secretory phase (56.2 +/- 2.9)% than those in early proliferative phase (31.8 +/- 2.6)%, late proliferative phase (32.2 +/- 2.3)% and early secretory phase (32.5 +/- 1.6)% (P < 0.01). (2) Patients with unexplained infertility did not have an increase of endometrial HOXA10 mRNA level in mid and late secretory phase, as compared with the controls (P < 0.01).

Conclusions: (1) High expression of HOXA10 gene during mid and late secretory phase indicated that HOXA10 gene may involve in implantation. (2) Aberrant HOXA10 expression of patients with unexplained infertility suggests that altered development of endometrium at the molecular level may contribute to the aetiology of infertility. (3) HOXA10 gene may play a role in decidua lization of endometrium during early pregnancy.