THE ASSOCIATION BETWEEN MATRIX METALLOPROTEINASE-1 (MMP-1) GENE POLYMORPHISM -1607 1G/2G (rs1799750) AND BREAST CANCER METASTASIS

Abstrak

Breast cancer is the most common malignancy among Indonesian women, with high rates of late-stage diagnosis frequently resulting in metastasis. Matrix metalloproteinase-1 (MMP-1) plays a crucial role in extracellular matrix degradation and the invasion-metastasis cascade. The functional promoter polymorphism -1607 1G/2G (rs1799750) in the MMP-1 gene increases transcriptional activity due to an extra guanine insertion in the 2G allele, potentially elevating metastatic risk. However, this association has been understudied in Indonesian populations. This study aimed to examine the relationship between MMP-1 rs1799750 polymorphism and metastatic status in breast cancer patients at the Integrated Biomedical Laboratory, Faculty of Medicine, Udayana University. An observational analytic cross-sectional study was conducted using archived venous blood samples from 24 breast cancer patients. Genotyping was performed via genomic DNA isolation, PCR amplification, and Sanger sequencing. Metastasis status (metastatic vs. non-metastatic) was correlated with genotypes using Chi-Square and Fisher's Exact Tests, with Odds Ratios (OR) calculated under a dominant 2G allele model. Of the 24 patients, 6 (25%) exhibited metastasis while 18 (75%) were non-metastatic. Genotype distribution was 1G/1G 75%, 1G/2G 20.8%, and 2G/2G 4.2%. Initial Chi-Square analysis showed a significant association (p=0.017). Further analysis using the dominant 2G model (2G/2G + 1G/2G vs. 1G/1G) yielded p=0.006 (Pearson Chi-Square) and p=0.018 (Fisher's Exact Test), with OR=16.0 (95% CI: 1.694–151.110). A significant association exists between MMP-1 rs1799750 polymorphism (dominant 2G allele model) and increased risk of breast cancer metastasis in this population.