Age-dependent differences in tumor cell polarity in endometrial carcinomas

Cell polarization is dependent on the structural asymmetry of apical and basolateral domains. Although clinical and biological heterogeneity of endometrial carcinomas in aged individuals has been proposed, little is known about the age-dependent differences in tumor morphology in terms of cell polarity. To clarify a possible significance of tumor cell polarity, a total of 92 cases of grade (G) 1 and G2 endometrial carcinomas (endometrioid type) were investigated.

Cell polarity for tumor glandular components was evaluated by examining the degree of three morphological parameters: nuclear ordering, basal positioning of nuclei within cells, and papillary snouting/glandular convolution. The results were also compared with findings for cell proliferation, expression of p21(Cip1)(p21), p27(Kip1)(p27), estrogen and progesterone receptors, p53 accumulation, and several clinicopathological factors.

Average values for each polarity parameter showed a stepwise decrease from tumors of pre-, through peri-, to post-menopausal patients, the difference being significant. Significantly high values for all polarity scores were also evident in tumors adjacent to secretory non-neoplastic endometrium as compared to those in non-secretory tissue. Positive correlations with low cell proliferation determined with respect to Ki-67 labeling indices, early clinical stage, and upper myometrial invasion were also noted, while there were no associations with expression of p21, p27, p53, and two hormone receptors.

These findings indicate that in endometrial carcinomas, the age-dependent differences in tumor cell polarity may be related to status of endogenous ovarian hormones, closely linked with cell proliferation and some prognostic factors.