Metabolic markers and HSP60 in chemonaive serous solid ovarian cancer versus ascites.

Objective: Metabolic pathway alterations in cancer are thought to be dependent upon tumor type-specific oncogenic activation and local nutrient and oxygen supply during disease progression. In serous ovarian cancer, the typical peritoneal spread of disease is caused by shedding of tumor cells into the abdominal cavity, often along with ascites formation. Not much is known about the metabolic features of these detached serous tumor cells. In this study, we investigate the messenger RNA (mRNA) expression of GAPDH (glycolytic glyceraldehyde 3-phosphate dehydrogenase) and PKM2 (pyruvate kinase isoform M2), ATP5B (mitochondrial β-F1-ATPase), and heat shock protein 60 in matched serous solid tumor and corresponding ascites.

Materials/methods: Fresh samples from solid tumor and corresponding ascites were prospectively collected from 40 patients undergoing primary surgery for suspected advanced ovarian cancer. Of these, 25 met the study eligibility criteria, that is, stage IIC to IV disease of the serous (24) or endometrioid (1) subtype with solid and ascites specimens containing 50% or more tumor cells and with good quality and quantity mRNA yield. All but 2 patients (92%) had type II disease. GAPDH, PKM2, ATP5B, and HSP60 mRNA expressions were assessed by real-time polymerase chain reaction. For each marker, the mRNA expression in solid tumor was pairwise compared with the corresponding expression in ascites using the Wilcoxon matched pairs signed rank sum test.

Results: In contrast to our hypothesis, the mRNA expression of analyzed metabolic markers and HSP60 did not significantly differ between matched solid tumor and malignant ascites.

Conclusions: Our results indicate that further expression changes in genes related to glycolysis or oxidative phosphorylation are not a prerequisite for serous cancer cell survival after detachment.