MMP9 and non-small cell lung carcinoma: The genotype and allele of MMP9 -1562C/T SNPs and MMP13-77A/G were not significantly different between cases and controls (p > 0.05), and the results demonstrated an association between the C allele and an increased serum level of NSCLC in MMP9-1562C/T (OR = 1.19, 95% CI = 0.75–1.89) compared with the A allele.