OBJECTIVETo investigate the effects of progesterone and progestin on the expressions of regulated on activation, normal T cell expressed and secreted (RANTES) in eutopic endometrium from patients with endometriosis.

METHODSWe collected the samples of endometrium from patients with endometriosis before operation or after insertion of levenorgestrel releasing intrauterine system (LNG-IUS), administration of oral medroxyprogesterone (MPA), or injection of gonadotrophic hormone releasing hormone agonist (GnRHa). Reverse transcription-polymerase chain raction was used to assay the expression of RANTES mRNA. On the other hand, progesterone (Po) and tumor necrosis factor-alpha (TNFalpha) of different concentrations and different manners were used to treat cultured cells in vitro. RANTES secretion was evaluated in the culture medium using ELISA. In order to evaluate the effect of Po on the secretion of RANTES under stimulation of TNFalpha, the cells were cultured in medium containing 100 U/ml TNFalpha and Po of different concentrations for 24 hours. After the pretreatment of Po for 48 hours at different concentrations, TNFalpha (100 U/ml, 16 h) was added to observe whether Po inhibits RANTES or not.

RESULTSThe expression of RANTES mRNA in eutopic endometrium of patients with endometriosis was significantly higher than in control group (28.0 +/- 9.0 vs. 22.0 +/- 5.6, P < 0.05). Following the exposures to LNG-IUS (24.0 +/- 4.2 vs. 25.9 +/- 4.2, P > 0.05) or GnRHa (23.0 +/- 12.9 vs. 26.9 +/- 5.2, P > 0.05), the expression of RANTES mRNA had no change. MPA significantly increased the expression of RANTES mRNA (42.6 +/- 3.1 vs. 24.3 +/- 5.7, P < 0.05). Po itself had no significant effect on the secretion of RANTES. Stimulated by Po and TNFalpha at the same time, the secretion of RANTES significantly increased. After pretreatment with Po for 48 hours, the reaction of RANTES to the stimulating effect of TNFalpha was down-regulated.

CONCLUSIONThe eutopic endometrium of patients with endometriosis has high chemotactic activity. It may be feasible to prevent and treat endometriosis with progestins.