Journal: Cell Death & Disease

Article Title: Pleiotropic actions of miR-21 highlight the critical role of deregulated stromal microRNAs during colorectal cancer progression

doi: 10.1038/cddis.2013.213

Figure Lengend Snippet: Ectopic miR-21 expression in MRC5 fibroblasts leads to upregulated MMP2 activity – SW480 CRC cell invasion is MMP2 dependent. ( a ) Representative experiment showing zymographic activity in CM 21 or CM SCC , with and without MMP2 inhibitor (MMP2inh). ( b ) Assessment of MMP2 activity by determination of zymographical band intensity. Results are expressed as a ratio of MMP2 activity in CM 21 compared with CM SCC in three independent experiments. ( c ) Transwell invasion assay using CM 21 or CM SCC as chemoattractant, with and without MMP2 inhibitor. Results represent the mean number of invading cells from four repeat experiments (* P <0.05)

Article Snippet: Specific MMP2 inhibitor I (Merck, Hoddesdon, UK), prepared at a stock concentration of 10 mM in DMSO was also added to the chemoattractant at a final concentration of 25 μ M, which achieved maximal inhibition of invasion with no cytotoxic effects (data not shown).

Techniques: Expressing, Activity Assay, Transwell Invasion Assay

Journal: Cell Death & Disease

Article Title: Pleiotropic actions of miR-21 highlight the critical role of deregulated stromal microRNAs during colorectal cancer progression

doi: 10.1038/cddis.2013.213

Figure Lengend Snippet: Proposed impact of deregulated miR-21 expression in CRC-associated stroma. Reciprocal signalling between stromal and epithelial cells (thin black arrows; left panel) is essential for normal colonic tissue homoeostasis. Early in cancer, this process is corrupted and secreted factors from transformed epithelial cells (dotted black arrow; central panel) initiate profound changes in adjacent stromal cells. Upregulated miR-21 expression in stromal fibroblasts supports TGF- β -dependent fibroblast-to-myofibroblast transdifferentiation (thick black arrow) and causes downregulated RECK expression. Myofibroblast-derived factors are important mediators of tumour progression (dotted red arrow; right panel), and although in the absence of TGF- β , miR-21 is not sufficient to initiate myofibroblast transdifferentiation, upregulated miR-21 does promote tumour proliferation and chemoresistance and enhanced tumour invasion through upregulated MMP2 activity

Article Snippet: Specific MMP2 inhibitor I (Merck, Hoddesdon, UK), prepared at a stock concentration of 10 mM in DMSO was also added to the chemoattractant at a final concentration of 25 μ M, which achieved maximal inhibition of invasion with no cytotoxic effects (data not shown).

Techniques: Expressing, Transformation Assay, Derivative Assay, Activity Assay