Non-small Cell Lung Cancer In Peripheral Blood Lymphocytes Of Ercc1 Mrna Level Of The Platinum Drug Treatment Response Correlation

Background: Combination chemotherapy based on platinum has been the primary therapy in advanced non-small-cell lung cancer(NSCLC). The response rate of the platinum-based chemotherapy reported by ECOG1594 TRIAL is only 17-21% and the median survival is 7.4-8.1 months. A plenty of studies indicate that an important mechanism of platinum resistance involves DNA repair capacity(DRC). The main pathway to repair platinum-DNA adducts is nucleotide excision repair pathway(NER). Excision repair cross-complementing 1(ERCC1) gene ,which codes for the crucial rate-limiting endonuclease in NER pathway, is involved in resistance to platinum. It has been shown that the patients with low ERCC1 expression are sensitive to platinum and their survivals after chemotherapy are longer than that of the patients with high ERCC1 expression.Purpose: to investigate whether ERCC1 mRNA expression levels in peripheral blood lymphocytes(PBLs) are associated with responses after treatment with a platinum-containing two drug regimen for patients with NSCLC .Materials and methods: Response was correlated with the level of ERCC1 mRNA in PBLs from 40 patients with NSCLC treated with platinum-containing combination chemotherapy. The relative expression levels of ERCC1/β-actin was measured using a semi-quantitative reverse transcription-PCR system.Results : ERCC1 expression was detectable in all patients. The overall response rate was 17.5%. There were no significant associations between ERCC1 expression and response. Although there was a trend toward decreased ERCC1 expression levels with good outcomes of the treatment, this difference failed to reach statistical significance(P=0.57). There were no significant differences in ERCC1 levels by gender, age, performance status, weight loss, histopathology, or tumor stage. The median ERCC1 expression levels were higher in adenocarcinomas compared with squamous cell carcinomas(0.84 vs 0.42),but with no significance(P=0.06).Conclusion: There are no significant associations between ERCC1 expression in PBLs of the NSCLC patients and response.