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 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 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

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

OBJECTIVE: To investigate the effect of gene silencing of Bmi-1 on proliferation regulation of CD44+ nasopharyngeal carcinoma cancer stem-like cells (CSC-LCs). METHOD: The sequence-specific short hairpin RNA lentivirus targeting at human Bmi-1 gene (LV-Bmi-1shRNA) was constructed and was used to infect CD44+ nasopharyngeal carcinoma cells which were sorted by flow cytometry. A lentiviral which included a random sequence was also designed to serve as a negative control. We employed fluorescence microscope and flow cytometry to detect infection efficiency; real-time PCR was used to detect Bmi-1 and its downstream gene while each protein expression level was confirmed by western blotting protocol; CCK-8 proliferation assay was applied to measure proliferation capacity; tumor spheroid assay was used to evaluate the self-renewal capacity. Colony formation assay was used to measure cell colony formation capability; flow cytometry analyzed cell cycle distribution. RESULT: The constructed LV-Bmi-1shRNA successfully infected into the CD44+ nasopharyngeal carcinoma cells. The infection efficiency could reach above 95%; LV-Bmi-lshRNA effectively inhibited Bmi-1 mRNA and protein expression, while the downstream gene p16INK4a and p14ARF mRNA as well as protein expression level were upregulated (P < 0.05). Notablely, the proliferation, colony formation, self-renewal capabilities of the experimental group decreased significantly (P < 0.05). In addition, the cell cycle arrested at the G0-G1 phase. CONCLUSION Gene silencing of Bmi-1 inhibited the proliferation, colony formation and self-renewal capabilities of the CD44+ nasopharyngeal carcinoma CSC-LCs, inhibited the cell cycle processes, which may mediate through Bmi1-p16INK4a/p14ARF-p53 pathway. Our experimental results indicated that Bmi-1 gene may play an important role in the maintenance of the stem cell-like characteristics of CD44+ nasopharyngeal carcinoma cells. Bmi-1 gene may be a potential new target for the treatment of nasopharyng al carcinoma in the future.
Carcinoma ; Cell Cycle ; Cell Division ; Cell Line, Tumor ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Gene Silencing ; Humans ; Hyaluronan Receptors ; metabolism ; Lentivirus ; Nasopharyngeal Carcinoma ; Nasopharyngeal Neoplasms ; genetics ; pathology ; Neoplastic Stem Cells ; cytology ; Polycomb Repressive Complex 1 ; genetics ; RNA, Messenger ; RNA, Small Interfering ; Tumor Suppressor Protein p14ARF ; metabolism ; Tumor Suppressor Protein p53 ; metabolism

The latest findings of our laboratory showed that Angelica sinensis polysaccharide (ASP) showed a definite effect in regulating the aging of hematopoietic stem cells. Leukemia is a type of malignant hematopoietic tumor in hematopoietic stem cells. There have been no relevant reports about ASP's effect in regulating the aging of leukemia cells. In this study, human acute myeloid leukemia (AML) KG1alpha cell lines in logarithmic growth phase were taken as the study object, and were divided into the ASP group, the cytarabine (Ara-C) group, the ASP + Ara-C group and the control group. The groups were respectively treated with different concentration of ASP, Ara-C and ASP + Ara-C for different periods, with the aim to study the effect of ASP combined with Ara-C in regulating the aging of human acute myeloid leukemia KG1alpha cell lines and its relevant mechanism. The results showed that ASP, Ara-C and ASP + Ara-C could obviously inhibit KG1alpha cell proliferation in vitro, block the cells in G0/G1 phase. The cells showed the aging morphological feature. The percentage of positive stained aging cells was dramatically increased, and could significantly up-regulate the expression of aging-related proteins P16 and RB, which were more obvious in the ASP + Ara-C group. In conclusion, the aging mechanism of KG1alpha cell induced by ASP and Ara-C may be related to the regulation of the expression of aging-related proteins, suggesting that the combined administration of ASP and anticancer drugs plays a better role in the treatment of leukemia .
Aging ; drug effects ; genetics ; metabolism ; Angelica sinensis ; chemistry ; Cell Cycle ; drug effects ; Cell Proliferation ; drug effects ; Cyclin-Dependent Kinase Inhibitor p16 ; genetics ; metabolism ; Humans ; Leukemia ; drug therapy ; genetics ; metabolism ; physiopathology ; Polysaccharides ; pharmacology ; Retinoblastoma Protein ; genetics ; metabolism ; Tumor Cells, Cultured

OBJECTIVETo observe the effect of extracts from Radix Ginseng, Radix Notoginseng and Rhizoma Chuanxiong (EXT) on delaying vascular smooth muscle cells (VSMCs) aging in aged rats.

METHODSVSMCs were obtained by the modified tissue explants technique and were shown to be positive for smooth muscle α-actin (SM-α-actin) by immunohistochemistry staining. VSMCs obtained from the young rats were served as the young control group; VSMCs obtained from the old rats were treated with no drug (the old group), with low dose extracts (20 mg/L, the EXT low-concentration group) and high dose extracts (40 mg/L, the EXT high concentration group), and with Probucal (10(-6) mol/L, the Probucal group) as a positive control. All groups were cultured for 24 h in the medium with 10% serum for 24 h followed by another 24 h in the serum-free medium. At the end of the 48-h culture, the following analyses were performed including determination of senescence-associated β-galactosidase (SAβ-Gal) activity, flow cytometry analysis of cell cycle, real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) analyses of p16, Cyclin D1, cyclin-dependent kinase 4 (CDK4) and retinoblastoma (Rb) mRNA expression, and Western blotting analyses of p16, cyclin D1, CDK4 and phosphoretinoblastoma (pRb) protein expressions.

RESULTS(1) In comparison to the younger rats, VSMCs from aged rats had significantly more SAβ-Gal positive cells (P<0.01) and more cells in S phase (P<0.05). VSMCs from the all treated groups showed a significant decrease in both SAβ-Gal positive cells (P<0.05) and S phase (P<0.05) compared to the old rats. (2) Compared with the young group, VSMCs in the old group had a significant decrease in p16 and Rb mRNA expression and a significant increase in Cyclin D1 and CDK4 mRNA expression. Compared with the old group, VSMCs in the treated groups had a significant increase in p16 and Rb mRNA expression and a significant decrease in Cyclin D1 and CDK4 mRNA expression (P<0.05). (3) Compared with the young group, VSMCs in the old group had a significant decrease in p16 protein expression and a significant increase in Cyclin D1, CDK4 and pRb protein expressions (P<0.05). Compared with the old group, VSMCs in the treated groups had a significant increase in p16 protein expression and a significant decrease in cyclinD1, CDK4 and pRb protein expressions (P<0.05).

CONCLUSIONSVSMCs obtained from old rats showed typical signs of cellular senescence and vascular aging. EXT had an effect on delaying senescence of VSMCs in vitro by altering the p16-cyclinD/CDK-Rb pathway.

Aging ; drug effects ; Animals ; Aorta ; cytology ; Cell Cycle ; drug effects ; Cellular Senescence ; drug effects ; Cyclin D1 ; genetics ; metabolism ; Cyclin-Dependent Kinase 4 ; genetics ; metabolism ; Cyclin-Dependent Kinase Inhibitor p16 ; genetics ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Flow Cytometry ; Gene Expression Regulation ; drug effects ; Male ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; cytology ; drug effects ; metabolism ; Panax ; Plant Extracts ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Wistar ; Retinoblastoma Protein ; genetics ; metabolism ; beta-Galactosidase ; 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

OBJECTIVETo investigate the clinical, pathological and immunohistochemical features of vulvar intraepithelial neoplasia (VIN).

METHODSAccording to the 2004 modified terminology of International Society for the Study of Vulvovaginal Diseases (ISSVD), the cases were diagnosed as VIN from patients who had performed vulvar biopsy in Beijing Wuzhou Women's Hospital from February 2009 to December 2011, which were reclassified as usual VIN and differentiated VIN. The clinical and pathological studies were conducted respectively. MaxVision immunohistochemical staining was used to detect the expression of Ki-67, p16 and p53 proteins.

RESULTSThere were 20 cases of VIN in 237 patients, and the incidence of VIN was 8.4% in all of contemporary vulvar biopsy. In 17 cases of usual VIN, mean age was 29.6 years, the lesion typically presented with atypical cells involving almost all layers of the epithelium, which was equivalent to the high-grade squamous intraepithelial neoplasia of cervix. Immunohistochemistry for Ki-67 and p16 was strongly positive in usual VIN. High risk human papillomavirus (HPV) detection was also positive. The incidence of differentiated VIN was less than usual VIN, and there were only 3 cases in this study. In differentiated VIN, patients aged over 50 years, with mean of 53.7 years, and the lesion most commonly presented with lichen sclerosis background. There were epithelial thickening and extending, and parakeratosis, and atypia was strictly confined to the basal and parabasal layers of the epithelium where the cells enlarged with abundant eosinophilic cytoplasm, presented with prominent nucleoli, increased cellularity and abnormal keratinization. In differentiated VIN, p53 was strongly positive, Ki-67 and p16 immunohistochemical expression was confined to the basal layer only.

CONCLUSIONSVIN is a precursor of invasive squamous cell carcinoma of the vulva. The modified terminology of ISSVD classifies VIN as high-grade lesions. Definitive pathological diagnosis of VIN plays an important role in its timely treatment and the prevention of vulvar carcinoma.

Adult ; Carcinoma in Situ ; metabolism ; pathology ; virology ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Female ; Humans ; Immunohistochemistry ; Ki-67 Antigen ; metabolism ; Middle Aged ; Papillomavirus Infections ; pathology ; Tumor Suppressor Protein p53 ; metabolism ; Vulvar Neoplasms ; metabolism ; pathology ; virology ; Young Adult