The Prognostic Significance of ALDH-1 and SOX9 Expression in Early Breast Cancer

Aldehyde dehydrogenase 1 (ALDH1) is an enzyme accountable for the detoxification of aldehydes. Sex-determining region Y-box 9 (SOX-9) plays a role in many biological and pathological processes. In this study, we aimed to evaluate the prognostic significance of ALDH1 and SOX9 expression in early breast cancer.
The expression of ALDH1 and SOX-9 was evaluated through immunohistochemistry derived from 50 eligible patients with early breast cancer included in the current prospective cohort study.
Positive expression of ALDH1 and SOX-9 were detected in 29 (58%) and 34 (68%) patients, respectively. The positive expressions of both markers were statistically significant associated with increasing the stage, lymph nodes metastasis, high Ki67 labeling index, and molecular subtypes (P < 0.001), along with with the biological markers; estrogen receptors, progesterone receptors, and human epidermal growth factor receptor 2 over-expressions, and large tumor size (P = 0.039, P = 0.022, P = 0.024 and P = 0.003 for ALDH1 expression and P = 0.012, P = 0.007, P = 0.004 , and P = 0.002 for SOX-9 expression, respectively). There is a significant positive association between the expression of ALDH1 and SOX-9, r (correlation coefficient) = +0.806 (P < 0.001). Local recurrence was associated with the positive expression of ALDH1 only (P = 0.045) and the disease progression was statistically significant and associated with the positive expression of both ALDH1 and SOX-9 (P = 0.038, P = 0.023, respectively). There was significant association of positive expression of SOX-9 with reduced 3-y disease-free survival (P = 0.039).
Positive expression of ALDH-1 and SOX9 were associated with aggressive histopathological features and poor outcome in early breast cancer and can be considered potential prognostic markers in this group of patients.