The Relationship Between rs3212986C>A Polymorphism and Tumor Stage in Lung Cancer Patients

Abstract

Background The nucleotide excision repair (NER) system is one of the most important deoxyribonucleic acid (DNA) repair mechanisms and is critical for chemotherapy resistance. We conducted the present study to investigate the association between two polymorphisms of excision of repair cross-complementing group 1 (ERCC1), the key component of the NER pathway, and the clinicopathological features of patients with non-small cell lung cancer (NSCLC). Methods A total of 38 patients with confirmed NSCLC were included in our study. DNA was extracted from peripheral blood. ERCC1 rs3212986 (8092) and rs11615 (118) were genotyped using molecular assays including polymerase chain reaction (PCR) with restriction fragment length polymorphism (by MboII and HpyCH4 enzymes) and sequencing. Results The PCR results indicated the correct performance of the genomics extraction and molecular protocols. The distribution of C/C, C/A and A/A genotypes at position 8092 was 42.10%, 47.36%, and 10.52% respectively (P=0.03). Multivariate regression analysis showed that there was a significant correlation between C8092A (rs3212986) polymorphism and metastasis, grade of the tumor, and response to treatment. Individuals carrying the rs3212986 CA genotype and A allele had a significantly worse response to the treatment. Also, the correlation between alteration at this genomics location and patients with NSCLC who used to smoke cigarettes was positive. However, no significant association was detected between rs11615 C118>T polymorphism and demographic characteristics of patients with NSCLC. Conclusion We concluded that in lung cancer patients there is a relationship between tumor stage and rs3212986C>A polymorphism.

Keywords: clinicopathological features; ercc1; nsclc; sequencing.

Figure 1. A. Extracted DNA from clinical samples.B. Amplicons associated with codon 118 of the ERCC1 gene. 1C. Amplicons associated with position 8092 of the ERCC1 gene. 1D. Products from the enzymatic digestive reaction. Digestion with MboII created 158bp (C/C), 41-117-158bp (C/A), and 41-117 bp (AA) at 8092 of ERCC1

Figure 2. A, B. A screenshot of the CHROMAS and MEGA4 software associated with the sequences of codon 118 of the ERCC1 gene.C,D. A screenshot of the CHROMAS and MEGA4 software related to the 8092 position of the ERCC1 gene

Figure 3. Direct relationship between grade of tumor and metastasis

TNM (Tumor, lymph-Node, Metastasis) frequency of C8092A polymorphism of ERCC1 gene of clinical samples (P<0.05, repeated measures of one-way analysis of variance data