First-Line Gemcitabine Plus Cisplatin in Nonsmall Cell Lung Cancer Patients

Aim. To evaluate the predictive value of RRM1, ERCC1, and BRCA1 expression in Chinese NSCLC patients treated with gemcitabine and cisplatin. Methods. Real-time fluorescent quantitative PCR was used to determine the RRM1, ERCC1, and BRCA1 mRNA expression levels of peripheral blood in late-stage NSCLC patients. The relationship between peripheral blood and mRNA expression in tumor tissues was analyzed further. Results. In terms of the tumor susceptibility to chemotherapy, the response rate in the low-RRM1-expression group was significantly greater than in the high-expression group (52.9% versus 5.9%, chi(2) test, P = 0.007). Subjects with low peripheral blood RRM1 expression survived longer than those with high RRM1 expression (15.5 versus 12.0 months, logrank 3.980, P = 0.046). Linear correlations were observed between peripheral blood and tumor tissue expression levels for RRM1 (R-2 = 0.045, P = 0.048) and BRCA1 (R-2 = 0.021, P = 0.001). Conclusion. Our study demonstrates increased survival and superior efficacy of gemcitabine and cisplatin combination chemotherapy in the treatment of NSCLC patients with low peripheral blood RRM1 expression. The linear correlations of the relative expression of mRNA were observed between peripheral blood and tumor tissue expression levels for RRM1 and BRCA1. RRM1 gene expression may contribute to chemotherapy sensitivity and may be an indicator of survival. It was significant to individual chemotherapy of patients with advanced NSCLC who do not have sufficient tumor tissue.