Aged ; Anthracosis ; complications ; metabolism ; pathology ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Humans ; Lung ; metabolism ; pathology ; Lung Neoplasms ; complications ; metabolism ; pathology ; Male ; Middle Aged ; Retinoblastoma Protein ; metabolism

Hepatocellular carcinomas (HCCs) show genomic alterations, including DNA rearrangements associated with HBV DNA integration, loss of heterozygosity, and chromosomal amplification. The genes most frequently involved are those encoding tumor suppressors. The p16INK4A tumor suppressor gene frequently displays genetic alteration in HCC tissues. The present study was performed to examine the incidence of methylated p16INK4A in the sera of liver cirrhosis (LC) and HCC patients, and to evaluate its role as a tumor marker of HCC. The sera of 23 LC patients and 46 HCC patients were examined in this study. The methylation status of p16INK4A was evaluated by methylation-specific PCR of serum samples. Methylated p16INK4A was detected in 17.4% (4/23) of LC patients and in 47.8% (22/46) of HCC patients. No association was demonstrated between p16INK4A methylation and serum AFP level. As the status of p16INK4A methylation was not associated with serum AFP level, it may have a role as a tumor marker of HCC.
Aged ; Carcinoma, Hepatocellular/*genetics ; DNA/metabolism ; *DNA Methylation ; Female ; Fibrosis ; *Genes, p16 ; Human ; Liver/pathology ; Liver Cirrhosis/*genetics ; Liver Neoplasms/*genetics ; Male ; Middle Aged ; Polymerase Chain Reaction ; Predictive Value of Tests ; Protein p16/*blood ; Sensitivity and Specificity ; Time Factors ; Tumor Markers, Biological

BubR1 mitotic checkpoint kinase monitors attachment of microtubules to kinetochores and links regulation of the chromosome-spindle attachment to mitotic checkpoint signaling. Defects in BubR1-mediated signaling severely perturb checkpoint control and are linked to diseases such as cancer. Studies using BubR1 mouse models suggest that BubR1 activities prevent premature aging and infertility. In this study, we show that BubR1 depletion in human adipose-derived mesenchymal stem cells (ASCs) precedes loss of the differentiation potential and induction of replicative senescence. These effects occur independently of p16(INK4A) expression and may involve DNA methylation. Our results reveal a new and unsuspected feature of BubR1 expression in regulation of adult stem cell differentiation.
*Adipogenesis ; Adipose Tissue/*cytology ; Adult ; Cell Aging ; Cells, Cultured ; DNA Methylation ; Gene Expression Regulation ; Genes, p16 ; Humans ; Mesenchymal Stem Cells/*cytology/metabolism ; Protein-Serine-Threonine Kinases/genetics/*metabolism

Aging is an independent risk factor for chronic diseases in the elderly, and understanding aging mechanisms is one of the keys to achieve early prevention and effective intervention for the diseases. Aging process is dynamic and systemic, making it difficult for mechanistic study. With recent advances in aging biomarkers and development of live-imaging technologies, more and more reporter mouse models have been generated, which can live monitor the aging process, and help investigate aging mechanisms at systemic level and develop intervention strategies. This review summarizes recent advances in live-imaging aging reporter mouse models based on widely used aging biomarkers (p16^Ink4a, p21^Waf1/Cip1, p53 and Glb1), and discusses their applications in aging research.
Humans ; Animals ; Mice ; Aged ; Aging ; Cyclin-Dependent Kinase Inhibitor p16/metabolism* ; Cyclin-Dependent Kinase Inhibitor p21/metabolism* ; Biomarkers ; Tumor Suppressor Protein p53

OBJECTIVETo study the expression of retinoic acid receptor-beta (RAR-beta) mRNA and p16, p53, Ki67 proteins in squamous-cell carcinoma of the esophagus and its precursor lesions in a high risk population.

METHODSA total of 397 tissue specimens were collected from individuals with normal mucosa (NM, n = 25), mild dysplasia (MiD, n = 69), moderate dysplasia (MoD, n = 106), severe dysplasia (SD, n = 51), carcinoma in situ (CIS, n = 78), and squamous-cell carcinoma (SC, n = 68). Expression of RAR-beta mRNA was detected by in situ hybridization, and that of p16, p53 and Ki67 proteins by immunohistochemistry.

RESULTSThe frequencies of RAR-beta mRNA expression in NM, MiD, MoD, SD, CIS and SC were 96.0%, 89.9%, 67.9%, 68.6%, 62.8%, and 63.2%, respectively. The frequencies of p16 expression were 88.0%, 71.0%, 64.2%, 51.0%, 53.8% and 52.9%; those of p53 expression were 4.0%, 39.1%, 57.5%, 52.9%, 67.9% and 69.1%; those of Ki67 expression were 0, 40.6%, 61.3%, 58.8%, 59.0% and 75.0%, respectively.

CONCLUSIONThere are no significant differences in four biomarkers expression between carcinoma of the esophagus and its precursor lesions.

Biomarkers, Tumor ; metabolism ; Carcinoma, Squamous Cell ; metabolism ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Esophageal Neoplasms ; metabolism ; Esophagus ; metabolism ; Humans ; Ki-67 Antigen ; metabolism ; Precancerous Conditions ; metabolism ; RNA, Messenger ; biosynthesis ; genetics ; Receptors, Retinoic Acid ; biosynthesis ; genetics ; Tumor Suppressor Protein p53 ; metabolism

Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Cystadenocarcinoma, Serous ; metabolism ; pathology ; Diagnosis, Differential ; Endometrial Neoplasms ; metabolism ; pathology ; Female ; Humans ; Precancerous Conditions ; metabolism ; pathology ; RNA-Binding Proteins ; metabolism ; Tumor Suppressor Protein p53 ; metabolism

Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Female ; Genes, p16 ; Genes, p53 ; Humans ; Hysterectomy ; methods ; Ki-67 Antigen ; metabolism ; Leiomyoma ; genetics ; metabolism ; pathology ; surgery ; Leiomyosarcoma ; genetics ; metabolism ; pathology ; surgery ; Prognosis ; Smooth Muscle Tumor ; genetics ; metabolism ; pathology ; surgery ; Tumor Suppressor Protein p53 ; metabolism ; Uterine Neoplasms ; genetics ; metabolism ; pathology ; surgery

OBJECTIVE(1) To investigate the promoter methylation status of gene p16(INK4a) and gene RB in breast carcinoma and the adjacent non-neoplastic hyperplastic epithelial tissue. (2) To study the correlation of p16(INK4a) gene expression at protein level with the abnormal gene methylation, the clinical manifestation and the pathological parameters.

METHODSMethylation status of promoters of p16(INK4a) gene and RB gene was detected by using methylation specific PCR in 46 cases of breast cancer, 22 cases of the adjacent non-neoplastic hyperplastic epithelium tissue and 7 cases of normal breast tissue. In addition, the p16(INK4a) gene protein expression level was also detected using immunohistochemical technique(SP method) in 46 cases of breast cancer and 22 cases of the adjacent hyperplastic epithelial tissue.

RESULTSThe methylation rate of p16(INK4a) gene was 23.9% (11/46) in breast cancer, 18.2% (4/22) in the adjacent non-neoplastic hyperplastic epithelial tissue and 1/7 in normal breast tissue, respectively. The methylation rate of RB gene was relatively low, which was 10.8% (5/46), 9.1% (2/22) and 0(0/7) in the above 3 groups, respectively. Methylation rate of p16(INK4a) gene and RB gene was not significantly different among the breast cancer, the adjacent non-neoplastic hyperplastic tissue and the normal tissues (P > 0.05). However, the methylation status of p16(INK4a) gene was closely correlated with its protein expression level and the negative ER expression result of the breast cancer (P < 0.05), but not correlated with the size of the cancer, differentiation status, lymph node metastasis, and age. The methylation status of RB gene was correlated with lymph node metastasis, but not with the size, the differentiation status, ER expression of the breast cancer and the age of the patients.

CONCLUSIONSThe abnormal methylation of p16(INK4a) gene may not play a significant role in the early stage of breast cancinogenesis, but may play a role of in the progression of the cancer. RB gene methylation may also be a indicator in choice to identify the progression and prognosis of breast cancer.

Adult ; Aged ; Breast Neoplasms ; genetics ; metabolism ; pathology ; Carcinoma, Ductal, Breast ; genetics ; metabolism ; pathology ; Carcinoma, Intraductal, Noninfiltrating ; genetics ; metabolism ; pathology ; Cyclin-Dependent Kinase Inhibitor p16 ; genetics ; metabolism ; DNA Methylation ; Female ; Gene Expression Regulation, Neoplastic ; Genes, p16 ; Humans ; Lymphatic Metastasis ; Middle Aged ; Receptors, Estrogen ; metabolism ; Retinoblastoma Protein ; genetics ; metabolism

It is known that human papillomavirus (HPV) infection can cause squamous cell neoplasms at several sites, such as cervix uteri carcinoma and oral squamous carcinoma. There is little information on the expression of HPV and its predictive markers in tumours of the major and minor salivary glands of the head and neck. We therefore assessed oral salivary gland neoplasms to identify associations between HPV and infection-related epidermal growth factor receptor (EGFR), cyclin-dependent kinase inhibitor 2A (CDKN2A/p16) and tumour protein p53 (TP53). Formalin-fixed, paraffin-embedded tissue samples from oral salivary gland carcinomas (n=51) and benign tumours (n=26) were analysed by polymerase chain reaction (PCR) analysis for several HPV species, including high-risk types 16 and 18. Evaluation of EGFR, CDKN2A, TP53 and cytomegalovirus (CMV) was performed by immunohistochemistry. Epstein-Barr virus (EBV) was evaluated by EBV-encoded RNA in situ hybridisation. We demonstrated that salivary gland tumours are not associated with HPV infection. The expression of EGFR, CDKN2A and TP53 may be associated with tumour pathology but is not induced by HPV. CMV and EBV were not detectable. In contrast to oral squamous cell carcinomas, HPV, CMV and EBV infections are not associated with malignant or benign neoplastic lesions of the salivary glands.
Alphapapillomavirus ; isolation & purification ; Cohort Studies ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Female ; Humans ; Male ; Middle Aged ; Polymerase Chain Reaction ; Receptor, Epidermal Growth Factor ; metabolism ; Salivary Gland Neoplasms ; metabolism ; virology ; Tumor Suppressor Protein p53 ; metabolism ; Tumor Virus Infections ; metabolism ; virology

OBJECTIVETo explore the molecular events and mechanism in the carcinogenesis of esophageal epithelium in the high incidence area of esophageal carcinoma.

METHODSEpithelial cells collected from the high incidence area of esophageal carcinoma were used to detect DNA content and ploidy by propidium iodide(PI) stain. The expressions of p53, p16 and cyclin D1 were stained by indirect immunofluorescence of fluorescein isothiocyanate(FTTC), which were detected by flow cytometry (FCM).

RESULTSDuring the process of carcinogenesis, DNA content increased significantly. The diploid cells decreased while heteroploid cells increased sharply, with a heteroploidy rate of 84.2%. At the same time, the p53 protein accumulated and p16 was deleted. The positive rates of p53 and oncogene cyclin D1 were both 100%(5/5, 6/6) in the cancer group.

CONCLUSIONIn the early carcinogenesis of esophageal epithelium, DNA content and heteroploidy rates increase with tumor suppressor gene p16 deletion and p53 protein accumulation while oncogene cyclin D1 is overexpressed. Multiple molecular events have already occurred when esophageal carcinoma develops.

Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; DNA, Neoplasm ; metabolism ; Esophageal Neoplasms ; genetics ; metabolism ; pathology ; Flow Cytometry ; Gene Expression ; Humans ; Precancerous Conditions ; genetics ; Tumor Suppressor Protein p53 ; metabolism