Cycle-related Proteins Cyclin D1 Research Articles

Expression of cyclin D1 and cyclin E significantly associates with human papillomavirus subtypes in Bowenoid papulosis

Human papillomavirus (HPV) incorporates high-risk HPV (hrHPV) and low-risk HPV (lrHPV) subtypes according to its contribution to oncogenesis. Different HPV subtypes could regulate the cell cycle of infected cells at different levels. To date, the expression of cyclin D1 and cyclin E in Bowenoid papulosis (BP) tissues and its association with HPV infection still remains elusive. In the present study, genotyping was performed to identify the HPV subtypes in 44 BP specimens. In addition, immunohistochemistry was performed to detect the expression of cell cycle related proteins cyclin D1 and cyclin E in BP tissues as well as normal tissues. We found that there were 20 patients with hrHPV subtypes, 6 patients with lrHPV subtypes, and 18 patients with combined high and low (hr/lr) HPV subtypes. Cyclin D1 expression in patients with hrHPV subtypes (P=0.0408), in patients with lrHPV subtypes (P=0.0002) and in patients with hr/lr HPV subtypes (P=0.0047) was significantly higher than that in normal controls, respectively. Cyclin D1 expression in patients with hr/lr HPV subtypes (P<0.0001) and in patients with lrHPV subtypes (P=0.0244) was significantly higher than that in patients with hrHPV subtypes, respectively. Cyclin E expression in patients with hrHPV subtypes (P<0.0001), in patients with lrHPV subtypes (P=0.0005), and in patients with hr/lr HPV subtypes (P<0.0001) was significantly higher than that in normal controls, respectively. Cyclin E expression in patients with hrHPV subtypes was significantly higher than that in patients with lrHPV subtypes (P=0.0032). Our data suggest that HPV infection is strongly associated with the pathogenesis of BP, and further support the notion that HPV may be involved in the regulation of the expression of cell cycle related proteins, cyclin D1 and cyclin E, in the pathogenesis of BP.

The CDK4/6 Inhibitor PD0332991 Reverses Epithelial Dysplasia Associated with Abnormal Activation of the Cyclin-CDK-Rb Pathway

Loss of normal growth control is a hallmark of cancer progression. Therefore, understanding the early mechanisms of normal growth regulation and the changes that occur during preneoplasia may provide insights of both diagnostic and therapeutic importance. Models of dysplasia that help elucidate the mechanisms responsible for disease progression are useful in highlighting potential targets for prevention. An important strategy in cancer prevention treatment programs is to reduce hyperplasia and dysplasia. This study identified abnormal upregulation of cell cycle-related proteins cyclin D1, cyclin-dependent kinase (CDK)4, CDK6, and phosphorylated retinoblastoma protein (pRb) as mechanisms responsible for maintenance of hyperplasia and dysplasia following downregulation of the initiating viral oncoprotein Simian virus 40 (SV40) T antigen. Significantly, p53 was not required for successful reversal of hyperplasia and dysplasia. Ligand-induced activation of retinoid X receptor and PPARγ agonists attenuated cyclin D1 and CDK6 but not CDK4 or phosphorylated pRb upregulation with limited reversal of hyperplasia and dysplasia. PD0332991, an orally available CDK4/6 inhibitor, was able to prevent upregulation of cyclin D1 and CDK6 as well as CDK4 and phosphorylated pRb and this correlated with a more profound reversal of hyperplasia and dysplasia. In summary, the study distinguished CDK4 and phosphorylated pRb as targets for chemoprevention regimens targeting reversal of hyperplasia and dysplasia.

Effect of human papillomavirus on cell cycle-related proteins p16INK4A, p21waf1/cip1, p53 and cyclin D1 in sinonasal inverted papilloma and laryngeal carcinoma. An &lt;i&gt;in situ&lt;/i&gt; hybridization study

Human papillomavirus (HPV) infection is implicated as an important risk factor in the development of head and neck cancers. Many studies focusing on the relationships between HPV infection and cell cycle proteins immunoexpression in laryngeal lesions have provided contradictory results. The aim of this study was to evaluate the relationships between HPV DNA presence and p16INK4a, p21waf1/cip1, p53 and cyclin D1 immunoexpression in heterogenous HPV-positive and HPV-negative groups of laryngeal cancers and inverted papillomas. The HPV DNA expression was detected using an in situ hybridization method and immunoexpression of p16INK4a, p21waf1/cip1, p53 and cyclin D1 using immunohistochemistry. The immunoexpression of p21waf1/ /cip1 and p53 proteins was lower in the HPV-positive group compared to the HPV-negative group, although only the difference of p53 staining was statistically significant. The immunoexpression of p16INK4a and cyclin D1 was significantly increased in the HPV-positive group compared to the HPV-negative group. The increased immunoexpression of p16INK4a and cyclin D1, and the lower immunoexpression of p21waf1/cip1 and p53 in the HPV-positive group compared to the HPV-negative group, supports the hypothesis that HPV may play an important role in cell cycle dysregulation.

751 CORPORAL SMOOTH MUSCLE RELAXATION IS AFFECTED BY ABNORMAL LIPIDS METABOLISM RELATED DOWN-REGULATING OF ATP SYNTHASE

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research1 Apr 2011751 CORPORAL SMOOTH MUSCLE RELAXATION IS AFFECTED BY ABNORMAL LIPIDS METABOLISM RELATED DOWN-REGULATING OF ATP SYNTHASE Tao Xu and Jing li Tao XuTao Xu Beijing, China, People's Republic of More articles by this author and Jing liJing li Beijing, China, People's Republic of More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.1776AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Primary risk factors of ED include: hypertension, hyperlipidemia, diabetes, coronary and peripheral vascular disease, pelvic organ damage or spinal cord injury or surgery. Our preliminary study found that as society changes in lifestyle and the popularity of metabolism disorders, in addition to the traditional view on ED that the nerve damage and vascular factors caused erectile dysfunction, the metabolic factors play more and more important roles in ED. The purpose of this article is to figure out the dysfunction of corporal smooth muscle itself with aging and metabolic disorders. Whether diastolic dysfunction and fibrosis of corporal smooth muscle cells also caused the erectile dysfunction and the possible target for intervention. METHODS leptin receptor knockout mice (db/dblepr−/−) and high-fat diet for 16 weeks mice model and it°−s control were using in our expetiments, we tested the erectile corpus cavernosum smooth muscle impulse conduction, and the key factor on energy generation were detected on the molecular biological level. RESULTS In vivo the ICP of HFD induced hyperglycemia mouse model are lower. The energy related protein ATP F1 subunit has a significant decrease compared with its control, cell cycle related protein cyclinD1 and akt has also decreased while the fatty acid synthase (FAS) upregulated. In the primary cultured human Corporal smooth muscle cell study, a 24h FFA treated significantly induced fatty acid accumulation in the cell as the oil red O staining showed, the energy and cell survival related protein decrease and the fatty acid oxidation decreased while inflammatory marker protein NFκB increased. CONCLUSIONS Diabetic mice models has erectile dysfunction, the corporal smooth muscle itself, as the impact of hyperglycimia and hyperinsulindimia appeared to decline in ATP synthase protein levels and promote corporal smooth muscle to be in inflammatory state may affect the cavernous smooth muscle structure and downregulate the energy generation which might cause erectile dysfunction. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e302 Peer Review Report Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Tao Xu Beijing, China, People's Republic of More articles by this author Jing li Beijing, China, People's Republic of More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Expression of cell cycle related proteins cyclin D1, p53 and p21&lt;SUP&gt;WAF1/Cip1&lt;/SUP&gt; in esophageal squamous cell carcinoma

Dysregulation of cell cycle control, especially G1/S phase transition, is implicated in the pathogenesis of most human cancers, including esophageal squamous cell carcinoma (ESCC). However, the clinicopathological significance of aberrant expression of G1/S phase-related proteins in ESCC remains unclear. In the present study, cyclin D1, p21WAF1/Cip1 and p53 protein expression were examined in 148 ESCC cases using immunohistochemistry combined with tissue microarray. We then analyzed the correlations between their expression and clinicopathological parameters and found that overexpression of p53 was associated with lymph node metastasis (P=0.001). p21WAF1/Cip1 down-regulation was an independent prognostic factor by multivariate analysis (RR=0.418, P<0.001). Further more, array-CGH results revealed that cyclin D1 gene was amplified in 45.4% of ESCC patients. This study confirms that dysregulation of G1/S related genes is common in ESCC and reduced expression of p21WAF1/Cip1 protein can predict shorter overall survival time of patients with ESCC.

Diazoxide-Mediated Growth Inhibition in Human Lung Cancer Cells via Downregulation of β-Catenin-Mediated Cyclin D1 Transcription

Treatment of various types of cells with the mitochondrial ATP-sensitive K(+) channel opener, diazoxide, preconditions cells to subsequent injuries and inhibits apoptosis. However, the role and mechanism(s) of diazoxide in solid tumor cell growth are largely unknown. Here we demonstrate that diazoxide inhibited the proliferation of lung cancer cells as well as the transcription of cell cycle-related protein Cyclin D1. Cyclin D1 overexpression inhibited the negative role of diazoxide in cell cycle progression. We further explored the mechanisms by which diazoxide affected Cyclin D1 transcription and found that the beta-catenin transcription factor was downregulated by diazoxide, with a corresponding decrease in Cyclin D1 promoter activity. Taken together, these results suggest that diazoxide inhibits lung cancer cell proliferation via downregulation of Cyclin D1 transcription, which may have important therapeutic implications in lung cancer patients.

Arsenic trioxide-mediated growth inhibition in gallbladder carcinoma cells via down-regulation of Cyclin D1 transcription mediated by Sp1 transcription factor

Gallbladder carcinoma (GBC), an aggressive and mostly lethal malignancy, is known to be resistant to a number of drug stimuli. Here, we demonstrated that arsenic trioxide inhibited the proliferation of gallbladder carcinoma in vivo and in vitro as well as the transcription of cell cycle-related protein Cyclin D1. And, Cyclin D1 overexpression inhibited the negative role of arsenic trioxide in cell cycle progression. We further explored the mechanisms by which arsenic trioxide affected Cyclin D1 transcription and found that the Sp1 transcription factor was down-regulated by arsenic trioxide, with a corresponding decrease in Cyclin D1 promoter activity. Taken together, these results suggested that arsenic trioxide inhibited gallbladder carcinoma cell proliferation via down-regulation of Cyclin D1 transcription in a Sp1-dependent manner, which provided a new mechanism of arsenic trioxide-involved cell proliferation and may have important therapeutic implications in gallbladder carcinoma patients.

Mechanism of apoptotic effects induced selectively by ursodeoxycholic acid on human hepatoma cell lines

To investigate the effects of ursodeoxycholic acid (UDCA) on apoptosis and proliferation of hepatoma cell lines. Human hepatoma cell lines HepG2 and BEL 7402 were cultured in medium supplemented with different concentrations of UDCA, normal human hepatic line L-02 was used as control. Cell proliferation, apoptosis and gene expression were detected using methyl thiazolyl tetrazolium (MTT) assay, flow cytometry, Western blot, DNA ladder assay, electron microscopy, and immunocytochemistry. Ursodeoxycholic acid inhibited the proliferation of HepG2 and BEL7402 cell lines in a dose-dependent manner. Ursodeoxycholic acid can change cell cycle distribution of HepG2 and BEL7402, the proportion of cells in G0-G1 phase increased whereas the proportion of S phase cells and G2-M phase cells decreased. Ursodeoxycholic acid arrested the cell cycle in G0-G1 phase by down-regulating the cell cycle related proteins cyclin D1, D3 and retinoblastoma protein (p(Rb)). The apoptotic rates of HepG2 and BEL7402 treated with UDCA (1.0 mmol/L) were significantly higher than those of control. In the HepG2 and BEL7402 treated with UDCA, expression of bcl-2 decreased whereas expression of Bax increased, the nuclear fragmentation and chromosomal condensed, cells shrank and lost attachment, apoptotic bodies and DNA ladders appeared. UDCA had no effect in inducing apoptosis on L-02 cell lines. UDCA can selectively inhibit proliferation and induce apoptosis of HepG2 and BEL7402 cell lines by blocking cell cycle and regulating the expression of Bax/bcl-2 genes.

Immunohistochemical studies on the expression pattern of molecular chaperones HSC70 and HSP25 and cell cycle-related proteins cyclin D1 and PCNA in rat liver after thioacetamide intoxication

Intoxication of rats with thioacetamide (TAA) is a model system to investigate mechanisms involved in liver cell death and tissue reconstitution. Our study was undertaken to determine by immunohistochemistry the expression pattern of the cytoprotective chaperone proteins HSC70 and HSP25 and proliferation markers cyclin D1 and PCNA in livers of Wistar rats intraperitoneally injected with TAA at a single dose of 50 mg/kg. For each protein studied we observed distinct dynamic changes in appearance and localization in liver lobules. During 24-36 h after TAA injection the HSC70 cytoplasmic immunoreaction gradually disappeared from hepatocytes localized around central veins and a shift of immunostaining to cell nuclei took place. Then, 36-48 h after TAA injection the HSC70 cytoplasmic immunoreaction reappeared with the highest intensity in hepatocytes surrounding the areas of inflammatory cells. HSP25, undetectable in control hepatocytes began to appear at approximately 36 h after TAA injection and HSP25-immunopositive cells formed a characteristic ring around areas of inflammation. Of the proteins studied, the most rapid reaction to TAA was observed for cyclin D1. As early as 15 min after TAA administration cyclin D1-positive hepatocytes appeared in intermediate and periportal areas of liver lobules and a subsequent shift of staining to centrilobular hepatocytes took place at 36 and 48 h. There was no correlation of cyclin D1 localization either with PCNA-positive cells or mitotic cells. Our observations suggest that in TAA-treated livers HSP25 and HSC70 proteins can play an anti-inflammatory role, and the early and distinct cyclin D1 expression is not related to proliferation of hepatocytes.

Flavopiridol inhibits smooth muscle cell proliferation in vitro and neointimal formation In vivo after carotid injury in the rat.

Smooth muscle cell (SMC) proliferation is a critical component of neointimal formation in many models of vascular injury and in human lesions as well. Cell-cycle inhibition by gene transfer techniques can block SMC proliferation and lesion formation in animal models, although these methods are not yet applicable to the treatment of human disease. Flavopiridol is a recently identified, potent, orally available cyclin-dependent kinase inhibitor. Using human aortic SMCs, we found that flavopiridol in concentrations as low as 75 nmol/L resulted in nearly complete inhibition of basic fibroblast growth factor-induced and thrombin-induced proliferation. At this dose, flavopiridol inhibited cyclin-dependent kinase activity, as measured by histone H1 phosphorylation, but had no effect on mitogen-activated protein kinase activation. Induction of the cell cycle-related proteins cyclin D1, proliferating cell nuclear antigen, and phosphorylated retinoblastoma protein was also blocked by flavopiridol. Flavopiridol had no effect on cellular viability. To test whether flavopiridol had a similar activity in vivo when administered orally, we examined neointimal formation in rat carotid arteries after balloon injury. Flavopiridol 5 mg/kg reduced neointimal area by 35% and 39% at 7 and 14 days, respectively, after injury. Flavopiridol inhibits SMC growth in vitro and in vivo. Its oral availability and selectivity for cyclin-dependent kinases make it a potential therapeutic tool in the treatment of SMC-rich vascular lesions.