Combination of TRAP1 and ERCC1 Expression Predicts Clinical Outcomes in Metastatic Colorectal Cancer Treated with Oxaliplatin/5-Fluorouracil.

The novel heat shock protein tumor necrosis factor receptor-associated protein 1 (TRAP1) is associated with multidrug resistance in colorectal cancer (CRC) cells in vitro. Excision repair cross-complementation group 1 (ERCC1) expression levels in tumor tissues also predict clinical outcomes in metastatic CRC patients receiving combination oxaliplatin and 5-fluorouracil treatment. We investigated whether TRAP1 and ERCC1 protein expression by immunohistochemistry predict clinical outcomes in CRC patients. The study population consisted of 56 patients with metastatic CRC who received first-line oxaliplatin/5-fluorouracil therapy. Clinical response and overall survival (OS) by levels of the markers TRAP1 and ERCC1 were evaluated. The rates of TRAP1 and ERCC1 expression were 21% and 52%, respectively. Patients negative for ERCC1 expression showed a tendency to respond to chemotherapy (p=0.066). Median OS was significantly longer in patients negative for TRAP1 than those positive for TRAP1 (p=0.023). Patients negative for ERCC1 expression also had a better OS than those positive for ERCC1 (p=0.021). The median OS was 30.9 months for patients negative for TRAP1 and ERCC1 compared to 13.2 months for those positive for TRAP1 and/or positive for ERCC1 expression (p=0.006). The combination of TRAP1 and ERCC1 expression was significantly associated with the response to chemotherapy (p=0.046) and independently predicted median OS in multivariate analysis (hazard ratio, 2.98; 95% confidence interval, 1.18 to 7.49). The present study demonstrates that the combination of TRAP1 and ERCC1 expression predicts the survival of metastatic CRC patients who were treated with oxaliplatin/5-fluorouracil.