PIK3C2G copy number is associated with clinical outcomes of colorectal cancer patients treated with oxaliplatin

Purpose: To investigate whether the copy number of PIK3C2G is associated with clinical outcomes for stage III colorectal cancer (CRC) patients treated with oxaliplatin-based chemotherapy.

Methods: A total of 142 CRC patients who received first-line oxaliplatin-based chemotherapy after curative surgery in Ruijin Hospital and The Tenth People's Hospital were recruited in this study. Patients were enrolled between June 2006 and December 2011, with follow-up to January 2014. Quantitative real-time PCR method was used to detect the copy number of PIK3C2G. Cox proportional hazards model and Kaplan-Meier curves were used to analyze the association between PIK3C2G copy number and clinical outcome.

Results: In patients with stage III disease, low copy number of PIK3C2G was associated with increased risk of both recurrence (HR, 2.44, 95% CI, 1.33-4.47, P=0.004) and death (HR, 2.89, 95% CI, 1.49-5.60, P=0.002). Multivariate analysis also indicated that low PIK3C2G copy number was a significant and independent predictor of OS and RFS of stage III CRC.

Conclusions: PIK3C2G is capable of predicting the recurrence and overall survival of stage III CRC patients receiving oxaliplatin-based therapy.