Proteomic approaches in understanding a detected relationship between chemotherapy-induced nephrotoxicity and cell respiration in HK-2 cells.

Background/aims: Nephrotoxicity is a prominent component of the profile of chemotherapeutic agents and to date proteomics has represented the main technique to identify protein profiles in response to xenobiotic exposure.

Methods: We made use of two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight analysis to evaluate chemotoxicity effects of cisplatin (CPT) and carboplatin (CB) on proteins from human renal proximal tubule epithelial cells (HK-2).

Results: Tandem mass spectrometry analysis showed that ATP synthase subunit α and serine hydroxymethyltransferase were only expressed in HK-2 cells exposed to CPT. Since CPT causes damage in cellular respiration, we suggest that this might be a protective adaptation to CPT-induced nephrotoxicity. Thioredoxin-dependent peroxide reductase disappeared in the CPT group and was upregulated in the CB group, suggesting that CB exposure stimulates preventive apoptotic mechanisms. We suggest a relationship between chemotherapeutic agent-induced nephrotoxicity and cell respiration. The identification of proteins differentially expressed in HK-2 cells, when exposed to CPT and CB, not only supplies important information to understand the molecular action mechanisms, which are triggered by metal-based drugs in cell nephrotoxicity, but also can lead to the design of more effective anticancer drugs.

Conclusion: These results provide important insights into the investigation of possible biomarker(s) of toxicity that could eventually reduce the side effects of chemotherapeutic agents.