SET and MYND domain-containing protein 3 decreases sensitivity to dexamethasone and stimulates cell adhesion and migration in NIH3T3 cells.

SET and MYND domain-containing protein 3 (SMYD3) is a novel histone methyltransferase that plays an important role in transcriptional regulation in human carcinogenesis. It activates the transcription of a set of downstream genes. Of these downstream genes, there are several oncogenes and genes associated with cell adhesion (including those of N-Myc, CrkL, Wnt10b, L-selectin, CD31 and galectin-4), which have been shown to have effects on cell viability, adhesion, migration and metastasis by many studies. To determine whether SMYD3 has such functions, in this study, we examined these types of biological activities in mouse fibroblast NIH3T3 cells by stably transfecting the human SMYD3 gene. The SMYD3-gene-transfected cells showed an increased proliferation rate and became more resistant to cell death induced by dexamethasone. Furthermore, the SMYD3-transfected cells also exhibited increased rates of cell adhesion to both type IV collagen and endothelial cells, and enhanced cell migration ability in both two-dimensional and three-dimensional assays. This study is the first to show that the overexpression of the SMYD3 gene affects cell viability, adhesion and migration, indicating that SMYD3 may be a promising new target of therapeutic intervention for the treatment of cancers or other pathological processes associated with cell adhesion and migration.