The combination of aldehyde dehydrogenase 1 (ALDH1) and CD44 is associated with poor outcomes in endometrial cancer

Aldehyde dehydrogenase 1 (ALDH1) and CD44 have been established as biomarkers for predicting the survival of many types of cancer patients. This study evaluated the expression and clinical significance of these putative cancer-cell markers in a series of tumor samples from endometrial cancer (EC) patients using tissue microarray. We examined 245 endometrial samples, including 132 (53.87%) pre-malignancy lesions and 113 (46.12%) malignant endometrial lesions from biopsies or hysterectomies. We examined the expression of CD44 and ALDH1 in these samples using immunohistochemistry staining. Correlations in the relative expression of these markers with clinicopathological parameters were also assessed. A high level of expression of ALDH1 was found in 44.25% (50/113) of the endometrial cancer samples, which was significantly correlated with a poor overall survival rate (p = 0.035). High-level CD44 expression was found in 35.4% (40/113) of the cases and was also correlated with a poor overall survival rate (p = 0.035). A simultaneous high expression of both markers was correlated with an extremely poor overall survival (p = 0.013). Our results show that tumors with higher expressions of both ALDH1 and CD44 were related to a poorer overall survival rate among EC patients. The combination of ALDH1 and CD44 could be a promising marker for developing additional targeted therapy for severe endometrial cancers.