Decrease in Survival Rate of Colorectal Cancer Patients Due to Insertion of a Single Guanine Base in Promoter Sequences of Matrix Metalloproteinase-1 Gene (in Tehran Population)

Insertion or deletion of a guanine in -1607 at promoter region of matrix metalloproteinase-1 enzyme creates two allelic types for this gene in the population: 2G and 1G, respectively. 2G allele contains an extra binding site for ETS transcription factors that this may increase the level of gene expression. Therefore, aim of this study was investigation of the single Guanine insertion in the promoter gene and its association with colorectal cancer patient survival rate and tumor progression. Blood samples from 150 colorectal patients and 100 cases were extracted. The mean follow-up was 25 months (12-36 months). Cases and patients were genotyped using genomic DNA extraction and PCR-RFLP. Colorectal cancer patients were divided in two groups with activity of metastasis (M+) and without activity of metastasis (M-). 2G allele in metastasis group (55%) showed more frequency rather than controls (23%). Survival analyses showed that 3 years survival patients rate in the patients without metastasis activity carrying 1G allele (homo and heterozygote) was 81% and for 2G homozygote is 66% (p=0.04). The survival rate dependent to cancer was 90% and 71%, respectively (P=0.01). According to the results, it seems that patients carrying 1G allele show a better survival rate dependent on cancer as compared to patients who do not carry this allele.