Immunohistochemical expression of heat shock protein 27, in normal hyperplastic and neoplastic endometrium: correlation with estrogen and progesterone receptor status, p53, pRb and proliferation associated indices (PCNA, MIB1).

Heat shock protein 27 (HSP27) is a relatively small protein produced in response to pathophysiological stress. In the current prospective study the presence and localization of HSP27 was associated with other potential prognostic factors such as: estrogen and progesterone receptors, p53 and proliferative associated indices (MIB1, PCNA). One hundred and twenty-two samples of endometrial tissues (65 endometrial carcinomas, 28 adenomatous hyperplasias, 31 normal endometrium) were studied. Patient records were examined for FIGO stage, grade, and depth of myometrial invasion, histology and lympho-vascular space invasion. HSPp27 expression was lower in the group of carcinomas when compared with the cases of adenomatous hyperplasias (p < 0.0001), normal proliferative (p < 0.0001) and secretory endometrium (p = 0.02). HSP27 expression was higher in carcinomas from premenopausal women in comparison with women in menopausal status and postmenopausal status. Multivariate tests showed no statistical significance of HSP27 expression according to tumor grade and stage. A positive relationship between the expression of HSP27 expression and estrogen receptors (p = 0.0018) as well as with progesterone receptor (p = 0.0012) was found with linear regression analysis of variance. Our data showed that the lower HSP27 expression in endometrial carcinomas in comparison with hyperplastic and normal endometrium may indicate a decreased endogenous protection mechanism against the various stressful stimuli. This expression could be under hormonal control and does not seem to be correlated with other conventional or possible prognostic parameters.