Increased MTHFD2 expression is associated with poor prognosis in breast cancer.

The aim of this study was to investigate the expression levels of methylenetetrahydrofolate dehydrogenase (NADP + -dependent) 2 (MTHFD2) and the associated clinical implications in breast cancer. MTHFD2 expression was measured by Western blot and immunohistochemistry in 698 tissue sections taken from breast cancer patients. The relationship between MTHFD2 expression, clinicopathological parameters, and the prognosis of breast cancer was subsequently determined. In comparison with para-carcinoma tissue specimens, an enhanced expression of MTHFD2 was observed in breast cancer tissue specimens (P < 0.05). In total, 41.12 % (287/698) of breast cancer tissue specimens had high levels of MTHFD2. After universal and Spearman regression correlation analyses, MTHFD2 expression was found to correlate with tumor size, histological grade, lymph node metastasis, and distant metastases (P = 0.001, 0.002, 0.001, and 0.001, respectively). Furthermore, patients with MTHFD2-expressing tumors had a significantly poorer prognosis than those with no or low MTHFD2 expression. (P = 0.002). Using the Cox regression test, MTHFD2 was identified as an independent prognostic factor (P = 0.001). MTHFD2 was differentially expressed in breast cancer tissue. Therefore, this protein may be an independent prognostic factor and a potential therapeutic target for future breast cancer treatments.