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

OBJECTIVE: To analyze the relationship between and gene methylation with aging in the general population. METHODS: We collected peripheral blood samples from 284 male and 246 female healthy subjects for detection of methylation levels of and genes using quantitative methylation-specific PCR (qMSP). The relationship between the methylation levels of and genes and aging was analyzed using Spearman or Pearson correlation test. RESULTS: We found a significant positive correlation between the methylation levels of the two genes in these subjects ( < 0.05). In the overall population as well in the female subjects, methylation was found to be inversely correlated with age ( < 0.05). The methylation levels of and genes were inversely correlated with TG, ApoE, Lp(a) and AST in the overall population ( < 0.05). In both the female and male subjects, the methylation levels of the two genes were inversely correlated with Lp(a) ( < 0.05). In the male subjects, methylation was inversely correlated with AST ( < 0.05), while methylation was inversely correlated with HDL and ApoE ( < 0.05). In the female subjects, methylation was positively correlated with LDL and inversely correlated with ApoE and AST ( < 0.05). CONCLUSIONS The methylation levels of and are closely related to age and the levels of multiple proteins in healthy subjects.
Aging ; Cyclin-Dependent Kinase Inhibitor p15 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; DNA Methylation ; Female ; Humans ; Male ; Real-Time Polymerase Chain Reaction

Shenkang injection (SKI) is a classic prescription composed of Radix Astragali, rhubarb, Astragalus, Safflower, and Salvia. This treatment was approved by the State Food and Drug Administration of China in 1999 for treatment of chronic kidney diseases based on good efficacy and safety. This study aimed to investigate the protective effect of SKI against high glucose (HG)-induced renal tubular cell senescence and its underlying mechanism. Primary renal proximal tubule epithelial cells were cultured in (1) control medium (control group), medium containing 5 mmol/L glucose; (2) mannitol medium (mannitol group), medium containing 5 mmol/L glucose, and 25 mmol/L mannitol; (3) HG medium (HG group) containing 30 mmol/L glucose; (4) SKI treatment at high (200 mg/L), medium (100 mg/L), or low (50 mg/L) concentration in HG medium (HG + SKI group); or (5) 200 mg/L SKI treatment in control medium (control + SKI group) for 72 h. HG-induced senescent cells showed the emergence of senescence associated heterochromatin foci, up-regulation of P16 and cyclin D1, increased senescence-associated β-galactosidase activity, and elevated expression of membrane decoy receptor 2. SKI treatment potently prevented these changes in a dose-independent manner. SKI treatment prevented HG-induced up-regulation of pro-senescence molecule mammalian target of rapamycin and p66Shc and down-regulation of anti-senescence molecules klotho, sirt1, and peroxisome proliferator-activated receptor-g in renal tubular epithelial cells. SKI may be a novel strategy for protecting against HG-induced renal tubular cell senescence in treatment of diabetic nephropathy.
Animals ; Cells, Cultured ; Cellular Senescence ; drug effects ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Diabetic Nephropathies ; drug therapy ; Drugs, Chinese Herbal ; pharmacology ; Epithelial Cells ; drug effects ; metabolism ; Glucose ; Kidney Tubules, Proximal ; physiopathology ; Male ; Mice ; Mice, Inbred C57BL

OBJECTIVE: To investigate paraffin section thickness in immunohistochemical detection of p16 expression in cervical tissue samples. METHODS: p16 immunohistochemical staining was performed in 150 cases of chronic cervicitis, 126 cases of low-grade squamous intraepithelial lesions(LSIL), 96 cases of high-grade squamous intraepithelial lesions (HSIL) and 78 cases of cervical cancer from January 2014 to March 2018 in Zhongshan Boai Hospital. The results of p16 protein expression in paraffin sections with thickness of 2, 3, 4, 5 and 6 μm were compared using Logistic regression analysis. RESULTS: With the increase of slice thickness, the staining of p16 protein in nucleus gradually increased. The thickness of cervical slices in chronic cervicitis and cervical cancer samples had no significant effect on the positive rate of p16 protein(=7.817 and 1.332, both >0.05), while the thickness of slices in LSIL and HSIL samples had significant effect on the positive rate of p16 protein (=17.688 and 10.182, <0.05 or <0.01). The stable and reliable results were obtained when the slices were between 3 and 5 μm thick. CONCLUSIONS Paraffin sections with thickness of 3.0-5.0 μm are recommended for immnohistochemical staining of p16 protein in cervical tissue samples.
Biomarkers, Tumor ; genetics ; metabolism ; Cervical Intraepithelial Neoplasia ; Cyclin-Dependent Kinase Inhibitor p16 ; genetics ; metabolism ; Female ; Histocytological Preparation Techniques ; standards ; Humans ; Immunohistochemistry ; Paraffin ; Squamous Intraepithelial Lesions of the Cervix ; Uterine Cervical Neoplasms ; physiopathology

OBJECTIVETo study the effects of LIF combined with bFGF on the proliferation, stemness and senescence of hUC-MSC.

METHODSExperiments were divided into 4 groups: control group, in which the cells were treated with complete medium (α-MEM containing 10% FBS); group LIF, in which the cells were treated with complete medium containing 10 ng/ml LIF; group bFGF, in which the cells were treated with complete medium containing 10 ng/ml bFGF; combination group, in which the cells were treated with complete medium containing 10 ng/ml LIF and 10 ng/ml bFGF. The growth curves of hUC-MSC at passage 4 in different groups were assayed by cell counting kit 8. Cellular morphologic changes were observed under inverted phase contrast microscope; hUC-MSC senescence in different groups was detected by β-galactosidase staining. The expression of PCNA, P16, P21, P53, OCT4 and NANOG genes was detected by RT-PCR.

RESULTSThe cell growth curves of each group were similar to the S-shape; the cell proliferation rate from high to low as follows: that in the combination group > group bFGF > group LIF > control group. Senescence and declining of proliferation were observed at hUC-MSC very early in control group; the cells in group LIF maintained good cellular morphology at early stage, but cell proliferation was slow and late senescence was observed; a few cells in group bFGF presented signs of senescence, but with quick proliferation; the cells in combination group grew quickly and maintained cellular morphology of hUC-MSC for long time. The LIF and bFGF up-regulated the expression of PCNA, OCT4 and NANOG, while they down-regulated the expression of P16, P21, P53, and their combinative effects were more significant.

CONCLUSIONLIF combined with bFGF not only can promote the proliferation and maintenance of stemness of hUC-MSC, but also can delay the senescence of hUC-MSC.

Cell Cycle ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p21 ; metabolism ; Fibroblast Growth Factor 2 ; pharmacology ; Genes, Homeobox ; Humans ; Leukemia Inhibitory Factor ; pharmacology ; Mesenchymal Stromal Cells ; cytology ; drug effects ; Octamer Transcription Factor-3 ; metabolism ; Organic Chemicals ; Proliferating Cell Nuclear Antigen ; metabolism ; Tumor Suppressor Protein p53 ; metabolism ; Umbilical Cord ; cytology

OBJECTIVETo investigate the role of Tal1 gene, which is aberrantly expressed in 40%-60% of patients with T lymphocytic leukemia (T-ALL), in the proliferation of T-ALL cells.

METHODSWe established stable Jurkat-siTal1 and Jurkat-T1 cell lines by trasnfecting T-ALL Jurkat cells with lentiviral vectors to knock-down or overexpress Tal1. Jurkat cells transfected with negative control siRNAs for Tal1 knock-down (Jurkat-mock1) and over-expression(Jurkat-mock2) served as the control cells. The proliferation of the cells lines was assessed using CCK-8 assay, and the cell cycle distribution was determined by flow cytometry. The mRNA and protein expressions of cyclin-dependent kinase inhibitor 2 (CDKN2A) and cyclin-dependent kinase inhibitor 1 (CDKN2B) were measured by real-time RT-PCR and Western blotting, respectively.

RESULTSJurkat-T1 cells showed more active proliferation in vitro than Jurkat-mock2 cells, while Jurkat-siTal1 cells showed slower growth than Jurkat-mock1 cells. In Jurkat-T1 cells, G0/G1 phase cells were decreased and S phase cells increased compared with Jurkat-mock2 cells, and Jurkat-siTal1 cells showed increased G0/G1 phase cells and decreased S phase cells compared with Jurkat-mock1 cells. Real-time RT-PCR and Western blotting showed that Tal1 inhibited the cellular expression of CDKN2A and CDKN2B at both mRNA and protein levels.

CONCLUSIONTal1 promotes the growth and the transition from G0/G1 phase to S phase in T-ALL cells Jurkat by inhibiting the expressions of G0/G1 and S phase negative regulatory proteins CDKN2A and CDKN2B.

Apoptosis ; Basic Helix-Loop-Helix Transcription Factors ; metabolism ; Cell Cycle ; Cell Proliferation ; Cyclin-Dependent Kinase Inhibitor p15 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Humans ; Jurkat Cells ; Lentivirus ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; metabolism ; pathology ; Proto-Oncogene Proteins ; metabolism ; RNA, Small Interfering ; T-Cell Acute Lymphocytic Leukemia Protein 1

OBJECTIVETo investigate the expression of p16INK4a protein in breast cancer and analyze its clinical significance.

METHODSA total of 132 surgical specimens of primary breast cancer obtained between 2014 and 2015 were examined for expressions of ER, PR, CK5/6, Her-2 and p16INK4a proteins using immunohistochemistry.

RESULTSThe breast cancer samples were classified into 5 molecular subtypes, namely Luminal A (58 cases), Luminal B (32 cases), Her-2-positive (21 cases), basal-like (12 cases) and normal-like (9 cases) types. p16INK4a expression was negative in 7/132 (5.30%) cases, weakly positive in 15/132 (11.36%) cases, positive in 40/132 (30.30%) cases, and strongly positive in 70/132 (53.03%) cases. When categorizing negative and weakly positive cases into negative group and the positive and strongly positive cases into positive group, the total negative and positive expression rates of p16INK4a were 16.67% (22/132) and 83.33% (110/132) in the carcinoma tissues. Statistical analysis showed the expression intensity of p16INK4a differed significantly between the age groups (P<0.05) but was not significantly correlated with ER, PR, Her-2, molecular subtypes or metastasis of the tumors.

CONCLUSIONThe compensatory high expression of p16INK4a is the main mechanism of cell cycle deregulation in invasive breast cancer and can be an important specific molecular marker for invasive breast cancer.

Biomarkers, Tumor ; metabolism ; Breast Neoplasms ; classification ; diagnosis ; metabolism ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Female ; Humans ; Keratin-5 ; metabolism ; Keratin-6 ; metabolism ; Receptor, ErbB-2 ; metabolism ; Receptors, Estrogen ; metabolism ; Receptors, Progesterone ; 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 investigate the expression level of COX-2, p16(INK4A) and p53 in patients with classic Hodgkin's lymphoma (cHL), and to evaluate their correlation with prognosis.

METHODSThe clinical data and samples of 52 cHL cases were collected. Immunohistochemical staining was performed to analyze the proteins level mentioned above and in situ hybridization of EBV encoded RNA (EBER) to clarify the tumor EBV infection state. Correlation between the protein expression and prognosis of patients was analyzed.

RESULTSOf 52 cases, the male and female ratio was 1.6∶1, the age was from 22 to 68 years old. All lesions located primarily in lymph nodes. All samples from 52 cases were stained with COX-2, p16(INK4A) and p53, and the positive expression of COX-2 was found in 28 cases (53.8%）, that of p16(INK4A) in 25 cases (48.1%)and p53 in 42 cases (80.8%）. All patients were divided into two groups according to differences in age (<40 years/ ≥ 40 years), gender (male/female), EBV infection (yes/no), B symptoms (yes/no), and the Ann Arbor staging (Ⅰ-Ⅱ/Ⅲ-Ⅳ), the correlation with COX-2, p16(INK4A) and p53 expression were analyzed, and only p53 expression was correlated with Ann Arbor staging (P=0.027). The statistical analysis of correlations between COX- 2, p16(INK4A) and p53 showed that the expression of COX-2 was strongly correlated with p53 (P=0.008), and p16 (INK4A) was not related to either COX-2 or p53 (P=0.246 and 0.958). Kaplan- Meier univariate OS analysis using SPSS17.0 software showed that only COX-2 expression was an adverse prognostic factor for patients'event free survival (EFS) (P=0.003). Meanwhile COX-2 expression was a unique independent prognostic factor analyzed by COX proportional hazards regression model (HR=0.091, 95% CI 0.017-0.505, P=0.006).

CONCLUSIONThe expression rate of COX-2, p16 (INK4A) and p53 in the cHL were relatively high; and they were not statistically correlated with tumor EBV infection status; the COX-2 positive group had poor prognosis, but only event free survival time becomes statistically significant shorter. COX proportional hazard regression model was used to analyze the COX-2 expression as a independent adverse prognostic factors for EFS.

Adult ; Aged ; Cyclin-Dependent Kinase Inhibitor p16 ; genetics ; metabolism ; Cyclooxygenase 2 ; genetics ; metabolism ; Disease-Free Survival ; Epstein-Barr Virus Infections ; Female ; Hodgkin Disease ; diagnosis ; genetics ; metabolism ; Humans ; Immunohistochemistry ; Kaplan-Meier Estimate ; Male ; Middle Aged ; Prognosis ; Proportional Hazards Models ; Tumor Suppressor Protein p53 ; genetics ; metabolism ; Young Adult

OBJECTIVETo study the role of p16 gene mutation status as detected by fluorescence in-situ hybridization (FISH) and p16 protein expression as detected by immunohistochemistry in differential diagnosis of malignant mesothelioma and benign mesothelial hyperplasia.

METHODSp16 gene mutation status and protein expression were detected by FISH and immunohistochemistry respectively in 55 cases of pleural malignant mesothelioma and 30 cases of benign mesothelial hyperplasia.

RESULTSFISH study showed that the rate of p16 deletion in malignant mesothelioma (81.8%,45/55) was higher than that in benign mesothelial hyperplasia (3.3%,1/30). The difference was statistically significant (P<0.05). Immunohistochemical study showed that the rate of p16 protein expression in malignant mesothelioma (23.6%) was lower than that in benign mesothelial hyperplasia (76.7%). The difference was also statistically significant. The sensitivity and specificity of FISH in distinguishing between mesothelioma and reactive mesothelial hyperplasia were higher than those of immunohistochemistry.

CONCLUSIONSIn contrast to reactive mesothelial hyperplasia, p16 gene is deleted and p16 protein is not expressed in malignant mesothelioma. The sensitivity and specificity of FISH are higher than those of immunohistochemistry in the distinction.

Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Diagnosis, Differential ; Epithelium ; pathology ; Genes, p16 ; Humans ; Hyperplasia ; diagnosis ; genetics ; Immunohistochemistry ; In Situ Hybridization, Fluorescence ; Mesothelioma ; diagnosis ; genetics ; metabolism ; Mutation ; Pleura ; pathology ; Pleural Neoplasms ; diagnosis ; genetics ; metabolism ; Sensitivity and Specificity