Immunohistochemical expression of cancer stem cell related markers CD44 and CD133 in endometrial cancer.

The goal of this study was to detect the presence of cancer stem cell markers CD44 and CD133 in immunohistochemically stained samples of endometrial cancer and correlate their expression with clinicopathological variables to identify the impact of CD44 or CD133 expression on tumor behavior and endometrial carcinogenesis. Marker expression was analyzed in 62 endometrial cancer samples (57 endometrioid carcinoma and 5 carcinosarcoma) and 15 proliferative endometrium samples. We detected CD133 and CD44 expression in 87.09% and 79.03% respectively of the studied endometrial cancers, and the expression was significantly different from the normal group. CD44 expression decreased with myometrial invasive depth and lymph-vascular space invasion (LVSI), and these inverse relationships were significant (p=0.034, p=0.019, respectively). CD133 was more expressed by early stage tumor (FIGO I-II) compared with those having FIGO III to IV stage disease (p=0.021). The most notable conclusion of the present study is that CD44 and CD133 might participate in early-stage endometrial cancer carcinogenesis, and their overexpression may facilitate the early diagnosis of endometrial cancers. Analysis of our results supports the hypothesis that CD44 expression tends to decrease as the disease becomes invasive and progressive. So, we concluded that CD44 down-regulation might warn of a more aggressive course and may have a link with poorly prognosis carcinosarcomas. Further examination of the expression and function of CD44 and CD133 with a greater number of carcinosarcomas is warranted.