Expression of p21 and p53 in rat gingival and human oral epithelial cells after cyclosporine A treatment

Abstract

In the present study, higher p21 mRNA and protein expressions were observed after cyclosporine A treatment. Thus, an up-regulation of p21 expression, via a p53-independent pathway, by cyclosporine A in gingival and oral epithelial cells was suggested.

Cyclosporine A enhances apoptosis in gingival keratinocytes of rats and in OECM1 cells via the mitochondrial pathway

“…Recently, we reported that cyclosporine A up-regulated the expression of p21 in gingival epithelial cells and increased the stasis of cells in the G1/ G0 phase (7). Strong evidence suggests that p21 is one of the most important downstream target genes of p53, a tumor suppressor gene (8); however, studies have also shown that p21 may be induced by p53-independent pathways (32).…”

“…epithelial cells. In our recent study, higher expressions of p21 mRNA and protein, via a p53-independent pathway, were observed after treatment with cyclosporine A (7). Protein p21 is the founding member of the family of cyclin-dependent kinase inhibitors, which also includes p27 and p57 (8).…”

“…Studies have found that cyclosporine A up‐regulates epithelial growth factor and keratinocyte growth factor (5,6), both of which are produced by epithelial cells. In our recent study, higher expressions of p21 mRNA and protein, via a p53‐independent pathway, were observed after treatment with cyclosporine A (7). Protein p21 is the founding member of the family of cyclin‐dependent kinase inhibitors, which also includes p27 and p57 (8).…”

Cyclosporine A up‐regulates Sonic hedgehog in gingiva: role of the up‐regulation on gingival cell proliferation

“…SHH-expressing cells fail to exit S and G2/M phases and persist in the cycle (29); this induction of cell proliferation is accomplished by up-regulation of cyclin D1 and cyclin E, which promote pRB and G1 to S transition (9). In our previous studies (7,8,25), gingival expression of cyclin D1 and pRB, which are SHH-related genes/mediators, showed a significant increase after treatment with cyclosporine A. We thus speculated that cyclosporine A might up-regulate the expression of Shh and further modulate the proliferation of gingival cells.…”

An Immunohistochemical Expressions of BAD , MDM2 and P21 in Oral Squamous Cell Carcinoma

“…Over expression of MDM2 protein may reflect a persistent response to DNA damaging agents present in OSCC patients and it can be oncogenic independently of P53 via stimulation the Sphase inducing transcription factor E2F1/DP1 or via inhibiting tumor suppressor protein pRBmediated cell cycle arrest (11) . P21protein mediates cell cycle arrest to secure against DNA replication in cells with anchorage damaged molecules (12) .…”