The role of miRNA-21 and epithelial mesenchymal transition (EMT) process in colorectal cancer.

AIMS: The study was conducted to assess the expression levels of epithelial mesenchymal transition (EMT) proteins (E-cadherin, N-cadherin, snail-1 and vimentin) and miRNA-21. In addition, we correlated these data with clinicopathological features in Colorectal cancer. METHODS: H&E slides from a total of 59 formalin fixed paraffin embedded tissue blocks were examined by a pathologist to demarcate normal and tumour regions. Immunohistochemical analysis of mismatch repair proteins (MLH1, MSH2 and MSH6) and EMT markers (E-cadherin, N-cadherin, snail-1 and vimentin) was performed. The miRNA-21 expression levels were determined using qRT-PCR and the data was analysed using the relative quantification method. The Fisher's exact and Pearson's χ2 tests were used to correlate snail-1, E-cadherin, miRNA-21 and clinicopathological data. RESULTS: Our results showed a statistically significant correlation between high miRNA-21 expression levels and E-cadherin positive cases. There was also an association between high miRNA-21 expression levels and negative snail-1 expression. No significant correlation was seen between miRNA-21 expression levels and clinicopathological features. Moreover, high expression levels of miRNA-21 were significantly associated with the sporadic cases. CONCLUSIONS: Our data suggest that miRNA-21 in association with E-cadherin and snail-1 does not play a significant role in the development and progression of this disease.

A synthetic non-degradable polyethylene glycol hydrogel retards adverse post-infarct left ventricular remodeling.

BACKGROUND: Left ventricular remodeling after myocardial infarction is a key component of heart failure and it has long been postulated that it may result from increased wall stress. It has recently been suggested that an injectable, non-degradable polymer may limit pathological remodeling in a manner analogous to that of cardiac support devices. We have tested a non-degradable polyethylene glycol (PEG) gel in a rat infarction model. METHODS AND RESULTS: After permanent ligation of the left anterior descending artery in male Wistar rats, PEG gel reagents were injected into the infarcted region and polymerized in situ. At 4 weeks, fractional shortening and infarct volume were unchanged relative to a saline injected control, but the infarct-induced left ventricular end-diastolic diameter (LVEDD) increase was substantially reduced (43%, P < .05) and wall thinning was completely prevented. At 13 weeks, the LVEDD were similar for both saline- and PEG-injected hearts. The non-degradable PEG gels did elicit a macrophage-based inflammatory reaction. CONCLUSIONS: The injection of non-degradable synthetic gel was effective in ameliorating pathological remodeling in the immediate postinfarction healing phase, but was unable to prevent the dilation that occurred at later stages in the healed heart.