Prognostic significance of cytochrome C release and tissue lactate dehydrogenase in patients with breast cancer

Abstract

The aim of this study was to evaluate the prognostic significance of cytochrome c release and tissue lactate dehyrogenase (LDH) in patients with breast cancer. This study included 90 patients with breast cancer and 35 patients with benign breast lesions. In cytosolic fraction, release of cytochrome c from mitochondria to cytosol was detected by Western blot, while total LDH activity was measured spectrophotometrically. Tissue LDHA mRNA was assessed by RTPCR. We observed a significant increase in cytochrome c release, LDH activity and LDHA mRNA in patients with breast cancer compared to patients with benign breast lesions. Cytochrome c release was significantly declined in poorly differentiated tumors (grade 3)
compared to well-differentiated and moderately differentiated tumors (grades 1, 2); and in stages III and IV compared to stages I and II of
breast cancer. Levels of LDH activity and LDHA mRNA were remarkably elevated in breast cancer patients with grade 3 compared to those with grades 1, 2; and in stages III and IV compared to stages I and II of breast cancer. High levels of LDH activity and LDHA mRNA were detected in breast cancer patients with positive lymph node compared to those with negative lymph node. These data indicate that cytochrome c release, cytosolic LDH activity and tissue LDHA mRNA can be considered as useful prognostic markers in patients with breast cancer.

Keywords: Breast cancer, cytochrome c release, LDH, prognostic
markers