OBJECTIVES p21 Can both promote and inhibit tumorigenic processes. We explored the role of p21 in myelodysplastic syndrome (MDS). METHODS In this study, we analyzed p21 expression and p73 methylation in 88 patients with de novo MDS. RESULTS We found decreased expression of the p21 gene in higher-risk MDS compared with lower-risk groups or healthy controls (P < .05). Patients with p73 methyl...

Werner syndrome (WS) is a rare autosomal recessive progeria disease with genetic instability/cancer predisposition, thus a good model in understanding aging related carcinogenesis. Telomere dysfunction induced cellular senescence is essential in the manifestation of the WS phenotype. Our previous data has shown that p21 (encoded by Cdkn1a gene) could induce cellular senescence and suppress cell...

Aims—To clarify p21 expression in sinonasal lesions. Methods—Archived surgical specimens from 38 patients were investigated by means of immunohistochemistry. p21 staining was evaluated in the diVerent layers of the epithelium. In addition, human papillomavirus (HPV) infection and p53 protein overexpression were assessed and correlated with p21 expression. Results—p21 staining was negative in no...

LincRNA-p21 is a downstream long non-coding RNA (lncRNA) transcript of p53. LincRNA-p21 serves as a repressor in p53-dependent transcriptional responses and participates in diverse biological processes, including apoptosis, cell cycle, metabolism and pluripotency. However, the role of lincRNA-p21 in human hepatocellular carcinoma remains to be defined. Here in this work, we demonstrated that li...

Treatment with the stress agent prostaglandin A2 (PGA2) induces expression of the cyclin-dependent kinase inhibitor p21. Here, we present evidence that p21 expression increases through PGA2-triggered stabilization of the p21 mRNA and further show that these events require the mitogen-activated protein (MAP) kinase ERK. Binding experiments using either endogenous p21 mRNA or in vitro-labeled p21...

Rheumatoid arthritis (RA) is characterized by synovial hyperplasia and destruction of cartilage and bone. The fibroblast-like synoviocyte (FLS) population is central to the development of pannus by migrating into cartilage and bone. We demonstrated previously that expression of the cell cycle inhibitor p21 is significantly reduced in RA synovial lining, particularly in the FLS. The aim of this ...

The molecular events leading to progression toward androgen-independent prostate cancer (AIPC) are not fully understood. The p21 (p21) gene has been identified as a key factor for the regulation of cell growth. The expression of p21 was examined by immunohistochemical studies in 105 prostate cancer samples: (a) 7 of 30 (23%) androgen-dependent tumors; and (b) 36 of 75 (48%) androgen-independent...

During periods of genotoxic stress, the cyclin-dependent kinase inhibitor p21waf1cip1 (hereafter referred to as p21) is transcriptionally up-regulated by the p53 tumor suppressor and subsequently plays a key role in cellular growth arrest. Investigations have also indicated that p21 may regulate nucleotide excision repair, a critical pathway that removes carcinogenic DNA damage induced by UV li...

p21(WAF1) inhibits cyclin-cyclin-dependent kinase (Cdk) complexes, causing cell cycle arrest. p21(WAF1) contains p53-binding sites in its promoter and expression of p21(WAF1) is induced by functional p53. In the present work, we have studied the role of protein kinase C (PKC) in the induction of p21(WAF1) and show that induction of p21(WAF1) expression can occur by activation of PKC in cells ha...

p53-mediated increase in cyclin-dependent kinase inhibitor p21(WAF1) protein is thought to be the major mediator of cell cycle arrest after DNA damage. Previously p21 protein levels have been reported to increase or to decrease after UV irradiation. We show that p21 protein is degraded after irradiation of a variety of cell types with low but not high doses of UV. Cell cycle arrest occurs despi...