Immortalized mouse embryo fibroblasts are resistant to miR-290-induced senescence regardless of p53 status

Abstract

The prosenescence role of miR-290 and nocodazole has been documented in primary mouse embryo fibroblasts (MEF), while it is not clear whether immortal murine fibroblasts are still responsive to these senescence inducing stimuli. To establish this point, immortal murine fibroblasts with functional (NIH3T3) or nonfunctional p53 (I-MEF) and low levels of miR-290 were tested for their capability to undergo senescence after exposure to either nocodazole or miR-290. Our results clearly indicate that nocodazole induces senescence only in NIH3T3 cells with a functional p53 but not in I-MEF lacking a functional p53. miR-290 overexpression is unable to address any of the tested immortalized clones toward senescence, regardless of the p53 status, suggesting that the prosenescence role of miR-290 is specific for primary but not for immortal murine fibroblasts. Moreover our findings suggest that the mere downregulation of a potential tumor suppressor miRNA in a given cell type does not necessarily imply that it behaves as a tumor suppressor.

Effect of heat treatment on cytotoxicity of self-adhesive resin cements: Cell viability analysis

“…Cell adhesion, proliferation, and metabolism in 3T3, L929, and W138 fibroblast and osteoblast cell lines are among the parameters that have been investigated. [ 31 33 34 ] In the present study, we assessed the behavior of mouse fibroblasts according to modified parameters of Stanford. Although these cells are more sensitive to cytotoxicity than human cells, they are indicated for this type of study by the American National Standard ISO 10993-5 due to their reproducible growth rates, easy handling, and easy availability when compared with primary cells and in addition being an immortal cell line.…”

miR290-5p/292-5p Activate the Immunoglobulin kappa Locus in B Cell Development

“…Interestingly, the AAGUCC miRNAs, including miR* counterparts miR290-3p and miR292-3p, are not detected in our system (Figure S1). There are few validated targets for miR290-5p or miR292-5p, but this group may include p16 [38] (12578) and Lats1 (16798), two genes implicated in cell cycling.…”