Matrix Metalloproteinases (MMP)-1, -2, and -9 Gene Polymorphism in Papillary Thyroid Cancers (PTC):

Matrix metalloproteinases and genetic mouse models in cancer research: a mini-review

Carcinogenesis is a multistep and also a multifactorial process that involves agents like genetic and environmental factors. Matrix metalloproteinases (MMPs) are major proteolytic enzymes which are involved in cancer cell migration, invasion, and metastasis. Genetic variations in genes encoding the MMPs were shown in human studies to influence cancer risk and phenotypic features of a tumor. The complex role of MMPs seems to be important in the mechanism of carcinogenesis, but it is not well recognized. Rodent studies concentrated particularly on the better understanding of the biological functions of the MMPs and their impact on the pathological process, also through the modification of Mmp genes. This review presents current knowledge and the existing evidence on the importance of selected MMPs in genetic mouse models of cancer and human genetic association studies. Further, this work can be useful for scientists studying the role of the genetic impact of MMPs in carcinogenesis.

Meta-analysis of association between matrix metalloproteinases 2, 7 and 9 promoter polymorphisms and cancer risk

Matrix metalloproteinase (MMP) 2, MMP7 and MMP9 are important members of the MMP family. Four polymorphisms in the promoter region of these MMPs, which are MMP2 -1306 C>T, MMP2 -735 C>T, MMP7 -181 A>G and MMP9 -1562 C>T, have been reported to be functional and may contribute to genetic susceptibility to cancers. However, the associations between these polymorphisms and cancer risk remain inconclusive due to conflicting results from different case-control studies. To better evaluate the role of these polymorphisms in cancer development, we conducted a meta-analysis that included 51 studies, with more than 40,000 subjects. The results showed that under dominant genetic model, MMP2 -1306 T was associated with lower susceptibility to lung cancer [odds ratio (OR) = 0.50, 95% confidence interval (CI) 0.43-0.59, P(heterogeneity) = 0.147, I(2) = 44.1%], head and neck cancer (OR = 0.53, 95% CI 0.41-0.69, P(heterogeneity) = 0.974, I(2) = 0.0%) and oesophageal cancer (OR = 0.67, 95% CI 0.55-0.80, P(heterogeneity) = 0.593, I(2) = 0.0%); MMP2-735T was associated with lower risk in lung cancer (OR = 0.65, 95%CI 0.53-0.79, P(heterogeneity) = 0.42, I(2) = 0.0%) and oesophageal cancer (OR = 0.84, 95% CI 0.70-0.99, P(heterogeneity) = 0.206, I(2) = 37.4%); MMP7 -181 AG and GG genotype carriers had an increased gastric cancer risk (OR = 1.90, 95% CI 1.43-2.51, P(heterogeneity) = 0.992, I(2) = 0.0%) and MMP9 -1562 C>T was not associated with cancer risk in the whole group analysis (OR = 0.99, 95% CI 0.91-1.08, P(heterogeneity) = 0.419, I(2) = 3.0%) and subgroup analyses. In all, our meta-analysis suggests that MMP2 -1306 C>T, MMP2 -735 C>T and MMP7 -181 A>G may play allele-specific roles in cancer development, while MMP9 -1562 C>T may not be a major risk factor for most cancer types. Large case-control studies should be performed to clarify the possible roles of these four polymorphisms in different kinds of cancer in more detail.

Polymorphisms in the promoter regions of matrix metalloproteinases 1 and 3 and cancer risk: a meta-analysis of 50 case-control studies

Matrix metalloproteinase (MMP) 1 and MMP3 are enzymes that degrade the extracellular matrix and have been implicated to play an important role in cancer development. Many studies have been carried out on the association between polymorphisms of MMP1 -1607 1G>2G and MMP3 -1171 5A>6A and cancer risk. However, results from these studies remain inconclusive. Here, we performed a meta-analysis of >38 000 subjects to better assess the purported associations. For MMP1, -1607 2G/2G genotype carriers were found to have an increased risk of colorectal cancer [2G/2G versus 2G/1G + 1G/1G, odds ratio (OR) = 1.48, 95% confidence interval (CI) (1.26-1.74), P(heterogeneity) = 0.066, I(2) = 49.3%], head and neck cancer [2G/2G versus 2G/1G + 1G/1G, OR = 1.61, 95% CI (1.26-2.07), P(heterogeneity) = 0.002, I(2) = 64.7%] and renal cancer [2G/2G versus 2G/1G + 1G/1G, OR = 1.82, 95% CI (1.38-2.39), P(heterogeneity) = 0.589, I(2) = 0.0%] risk. For MMP3, no association was found between -1171 5A>6A polymorphism and cancer risk in the overall group [6A versus 5A, OR = 1.00, 95% CI (0.95-1.05), P(heterogeneity) = 0.124, I(2) = 24.9%] and individual cancer subgroups, but stratified analysis by smoking status showed that this polymorphism had different effects on smokers and non-smokers under recessive genetic model. In summary, our study suggests that MMP1 -1607 2G may be associated with an increased cancer risk for certain types of cancers, MMP3 -1171 5A>6A may not be a major risk factor for cancer, but it may be modified by certain environmental factors. Future studies with larger sample sizes are warranted to further evaluate these associations in more detail.