Elucidation of MMP-9 expression and association of MMP-9 rs3918242-1562 C/T promoter polymorphism in the progression of cervical cancer.

This study explores the expression of the MMP-9 gene through transcriptomic analysis and quantitative real-time PCR (qRT-PCR), along with the investigation of the promoter polymorphism rs3918242 (C-1562T) using RFLP, confirmed by Sanger sequencing. A total of 200 samples were analyzed, including 100 cervical squamous cell carcinoma tissues and 100 normal control samples. Results revealed a significant upregulation of MMP-9 mRNA expression in cancerous tissues compared to normal counterparts. Furthermore, analysis of the rs3918242 polymorphism showed a higher prevalence of the C allele among controls, while the T allele was more frequently observed in patients. Notably, individuals with the T/T genotype, under a recessive genetic model, exhibited a significantly increased risk of cervical cancer (p < 0.02; OR = 2.98; 95 % CI: 1.12-7.98). Although no strong association was found between the polymorphism and overall cervical cancer risk, elevated MMP-9 expression was closely linked to disease progression. Transcription factor binding analysis using TRANSFAC revealed that the C-to-T substitution disrupts an SP1 binding site, potentially contributing to increased gene expression. Additionally, assessments of mRNA and pre-mRNA secondary structures indicated that the rs3918242 polymorphism alters RNA conformation, with the C allele displaying higher structural stability than the T allele. These findings suggest that while the polymorphism may not directly confer susceptibility, it could influence gene regulation mechanisms relevant to the development of cervical cancer.