Changes in CoQ 10 /Lipids Ratio, Oxidative Stress, and Coenzyme Q 10 during First-Line Cisplatin-Based Chemotherapy in Patients with Metastatic Urothelial Carcinoma (mUC).

Oxidative stress plays an important role in cancer pathogenesis, and thiobarbituric acid-reactive substance level (TBARS)-a parameter of lipid peroxidation-has prognostic significance in chemotherapy-naive patients with metastatic urothelial carcinoma (mUC). However, the effect of cisplatin (CDDP)-based chemotherapy on oxidative stress, coenzyme Q 10 , and antioxidants remains unknown. The objective of this prospective study was to determine possible changes in the CoQ 10 (coenzyme Q 10 )/lipids ratio, antioxidants (α-tocopherol, γ-tocopherol, β-carotene, CoQ 10 ), total antioxidant status (TAS), and TBARS in plasma at baseline and during first-line chemotherapy based on CDDP in mUC subjects. In this prospective study, 63 consecutive patients were enrolled. The median age was 66 years (range 39-84), performance status according to the Eastern Cooperative Oncology Group (ECOG) was 2 in 7 subjects (11.1%), and visceral metastases were present in 31 (49.2%) patients. Plasma antioxidants were determined by HPLC and TAS and TBARS spectrophotometrically. After two courses of chemotherapy, we recorded significant enhancements compared to baseline for total cholesterol ( p < 0.0216), very low-density lipoprotein (VLDL) cholesterol ( p < 0.002), triacylglycerols ( p < 0.0083), α-tocopherol ( p < 0.0044), and coenzyme Q 10-TOTAL ( p < 0.0001). Ratios of CoQ 10 /total cholesterol, CoQ 10 /HDL-cholesterol, and CoQ 10 /LDL-cholesterol increased during chemotherapy vs. baseline ( p < 0.0048, p < 0.0101, p < 0.0032, respectively), while plasma TBARS declined ( p < 0.0004). The stimulation of antioxidants could be part of the defense mechanism during CDDP treatment. The increased index of CoQ 10-TOTAL /lipids could reflect the effect of CDDP protecting lipoproteins from peroxidation.