TNF alpha expression in hyperplastic endometrium

PROBLEM: Tumor necrosis factor-alpha (TNF alpha) is produced by the endomet rium, and it has been shown that this cytokine has cyclic variations throug h the menstrual cycle. METHOD OF STUDY: In this study we assessed TNF alpha, estradiol and progest erone levels in the endometrium and serum of 21 patients with recent abnorm al uterine bleeding (AUB). Eleven women showed histological diagnosis of en dometrial hyperplasia, and ten women showed normal endometrium. RESULTS: The TNF alpha value in the serum of patients with hyperplasia and in normal endometrium did not show significant differences (64.8 +/- 21.4 v s 77.6 +/- 14.8 pg). The amounts of TNF alpha released by hyperplastic endo metrial tissue were significantly higher than in control patients (258.8 +/ - 78.0 vs 140.6 +/- 79.8 pg/g; P < 0.001). Immunohistochemistry of hyperpla stic endometria showed a stronger staining than normal ones. Serum E-2 leve ls in patients with hyperplastic endometrium were 49.5 +/- 31.6 ng/mL, and in controls were 107.3 +/- 66.0 ng/mL. The levels of estradiol released by hyperplastic endometria were significantly lower than in normal endometria (152.7 +/- 60.0 vs 279.9 +/- 178.7 ng/g; P < 0.003). CONCLUSIONS: Hyperplastic endometria produce higher amounts of TNF alpha wi th respect to controls. These findings may explain the frequent bleeding ob served in the patients with endometrial hyperplasia, since TNF alpha promot es apoptosis and endometrial shedding.