Transcription activity of MMP-2 and MMP-9 metalloproteinase genes and their tissue inhibitor (TIMP-2) in acute coronary syndrome patients

Abstract

Acute coronary syndromes (ACS) are a consequence of coronary vessel atherosclerosis and they are a leading cause of death in industrialized countries. One of the ACS causative factors is the deranged ratio equilibrium of the matrix metalloproteinase/tissue inhibitor of metalloproteinases (MMPs/TIMPs). Assessment of transcriptional activity of metalloproteinase genes using Human Genome-U133A oligonucleotide microarrays and selection of candidate genes differentiating ACS patients from healthy subjects and finally, QRT-PCR (quantitative real time polymerase chain reaction) confirmation of the results. The study involved 67 ACS patients, admitted on a consecutive basis, to the Cardiology Clinic as well as 24 healthy subjects (control). Ribonucleic acid isolated from peripheral blood mononuclear cells was analyzed by QRT-PCR. Transcriptional activity of the analyzed gene was assessed with TaqMan gene expression assays. U Mann-Whitney test was used to compare the results. Homogeneity of the investigated group was assessed through hierarchical clusterization whereas the nine genes differentiating ACS patients from healthy persons were selected using the Bland-Altman technique. Among these genes three (platelet derived growth factor D, NUAK family SNF1-like kinase 1 and peroxisomal biogenesis factor 1) showed decreased transcriptional activity whereas the remaining six genes (MMP-2 and MMP-9, CDK5RAP3, transmembrane BAX inhibitor motif containing 1, adenylate cyclase-associated protein 1 and TIMP-2) were increased. MMP-2, MMP-9 and TIMP-2 were further characterized by QRT-PCR. The obtained results permit to conclude that the increased expression of MMP-2 and MMP-9 metalloproteinases and their tissue inhibitor (TIMP-2) is responsible for disturbed equilibrium of the metalloproteinase/tissue inhibitors system and as a consequence, for destabilization of atherosclerotic plaque and occurrence of the acute coronary syndrome in the investigated group of patients.