A study of matrix metalloproteinases in cancer and atherosclerosis

Abstract

Background: Matrix metalloproteinases (MMPs) have been shown to be involved in cancers and atherosclerosis, the leading causes of present day mortality. The objectives of the cancer element of this project were to investigate single nucleotide polymorphisms (SNPs) in MMP1 and MMP8 regarding breast cancer and malignant melanoma, and a functional characterisation of the genetic variants, including the MMP1 polymorphism rs19799750, previously associated with multiple cancers. The objective of the second part of this project was to investigate whether MMP8 played a role in the development of atherosclerotic lesions and if so, the underlying mechanisms. Methods/Results: Genetic investigations found the MMP8 SNP rs11225395 to be associated with the occurrence of both breast cancer and malignant melanoma; furthermore it was also associated with reduced lymph node metastasis, reduced cancer relapse and greater survival. Functional luciferase assays showed that the minor allele of the polymorphism has higher promoter activity in breast cancer and melanoma cell lines. They also showed haplotypic effects on MMP1 promoter activity in several cancer cell lines by the 2G allele of polymorphism rs1799750 and one or more MMP1 promoter SNPS. The second part of the study found an association between a MMP8 SNP and the extent of coronary atherosclerosis; additionally a relationship among MMP8 gene variation, plasma VCAM-1 level, and atherosclerosis progression was observed in a prospective study. Murine studies showed reduced atherosclerosis in MMP8/ApoE knockout mice compared with ApoE knockout littermate controls. Biochemical studies confirmed that MMP8 can convert angiotensin I to angiotensin II. 3 Conclusions: The data of the first part of this project support the notion that genetic polymorphisms in the MMP1 and MMP8 influence the expression of these genes and the development and progression of cancer. The results of the second part of this project indicate an important role of MMP8 in the pathogenesis of atherosclerosis.