Carcinoma, Hepatocellular/genetics* ; Computational Biology ; Humans ; Liver Neoplasms/genetics* ; Prognosis ; Proliferating Cell Nuclear Antigen

OBJECTIVE: Analysis of the correlation between telomerase and expression of its related proteins may provide insight into the molecular mechanism of nasopharyngeal carcinogenesis. Here, we investigate the effect of short hairpin RNA (shRNA) specific for human telomerase reverse transcriptase (hTERT) mRNA on the expression of proliferating cell nuclear antigen (PCNA) and Caspase-3 in nasopharyngeal carcinoma (CNE) cells. METHOD: shRNA expression vectors targeting the mRNA of hTERT were constructed. Cells were treated with the constructed expression vectors and telomerase activity was measured by telomeric repeat amplification ELISA (TRAP-ELISA). Cell viability was examined using the MTT assay. Cell apoptosis was detected by TUNEL method. The expression of PCNA and Caspase-3 proteins, was determined by Western blotting. RESULT: shRNA specific for hTERT mRNA significantly inhibited telomerase activity, suppressed cell viability and induced apoptosis in CNE cells. In addition, the expression of PCNA was inhibited, while the expression of Caspase-3 was up-regulated. CONCLUSION Our results suggest that shRNA directed against hTERT inhibits cell viability by regulating telomerase activity and its related protein expression in NPC cells. Therefore, RNA-interfering technology may be a promising strategy for the treatment of nasopharyngeal cancer.
Caspase 3 ; metabolism ; Cell Line, Tumor ; Cell Survival ; Humans ; Nasopharyngeal Neoplasms ; genetics ; metabolism ; Proliferating Cell Nuclear Antigen ; metabolism ; RNA, Small Interfering ; Telomerase ; genetics ; Transfection

To explore the effects of the physiological range of hydrostatic pressure on human bladder smooth muscle cells (HBSMCs) cultured in vitro, we used a hydrostatic compression device designed in our laboratory into the experiments, which were grouped by varied hydrostatic pressure gradients. Cellular morphology was observed with HE staining; cytoskeleton F-actin, cell cycle, both proliferating cell nuclear antigen (PCNA) and matrix metalloproteinase 7 (MMP-7) were detected respectively with immunofluorescence, flow cytometry and RT-PCR. We found that the proliferation, cytoskeleton and cycle distribution of HBSMCs were not obviously different among the groups of different hydrostatic pressure; however, the mRNA expression of MMP-7 exhibited a trend of first increasing and then declining as the pressure gradually rises. Thus the physiological range of hydrostatic pressure may not have significant influence on proliferation, morphology, skeleton, and cell cycle of HBSMCs, but it may have great effect on the expression of MMP-7.
Cells, Cultured ; Humans ; Hydrostatic Pressure ; Matrix Metalloproteinase 7 ; genetics ; metabolism ; Myocytes, Smooth Muscle ; cytology ; physiology ; Proliferating Cell Nuclear Antigen ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Urinary Bladder ; cytology

OBJECTIVETo study the effects of Box-3 region of the leukemia inhibitory factor receptor (LIFR) alpha-chain cytoplasmic domain on the proliferation and differentiation of HL-60 cells.

METHODSExpression vector of gp190CT3 was constructed and expressed in HL-60 cells. The expression level of gp190CT3 was assayed by immunocytochemistry. The growth of wild type and gp190CT3 transfected HL-60 cells were examined under microscope. The PCNA levels were assayed by Western blot, and the levels of CD15 by flow cytometry.

RESULTSThe gp190CT3 transfected HL-60 cells were enlarged in size and their proliferation was slower than that of wild type. The expression level of PCNA was down-regulated while the level of CD15 up-regulated in transfected HL-60 cells as compared with that of the wild type cells.

CONCLUSIONThe Box-3 region of the leukemia inhibitory factor receptor alpha-chain cytoplasmic domain (gp190CT3) participates the LIFR signal transduction in inhibiting the growth and inducing the differentiation of HL-60 cells.

Binding Sites ; genetics ; Blotting, Western ; Cell Differentiation ; genetics ; physiology ; Cell Proliferation ; Genetic Vectors ; genetics ; HL-60 Cells ; Humans ; Immunohistochemistry ; Lewis X Antigen ; metabolism ; Proliferating Cell Nuclear Antigen ; metabolism ; Receptors, OSM-LIF ; genetics ; metabolism ; Transfection

To investigate the role of progesterone receptor (PR) expression in malignant melanoma (MM), PR and proliferative cell nuclear antigen (PCNA) expression were immunohistochemistrically evaluated in a series of 35 specimens of MM, and the correlation between the immunohistochemistrical findings and clinicopathological data was also analyzed. PR expression was detected in 25.7% (9/35) of the patients with MM. No PR expression was observed in nevi. PR expression was inversely correlated with PCNA expression (r=-0.353, P=0.026). PR expression was slightly increased in females, subjects aged under 55 y, those with ulceration, non-acral subtype and diagnosis delay longer than 1 y, but the difference was not statistically significant. Selective expression of progesterone receptor in malignant melanoma might be correlated with inhibited tumor growth.
Gene Expression Regulation, Neoplastic ; Immunohistochemistry ; Melanoma/*metabolism ; Models, Biological ; Prognosis ; Proliferating Cell Nuclear Antigen/*metabolism ; Receptors, Progesterone/*biosynthesis ; Receptors, Progesterone/genetics ; Skin/metabolism ; Skin Neoplasms/metabolism

A common DNA polymerase can replicate DNA which functions normally. However, if DNA suffers damage, the genome can not be replicated by a common DNA polymerase because DNA lesions will block the replication apparatus. Another kind of DNA polymerases in organism, Y-family DNA polymerases which is also called translesion synthesis (TLS) polymerases, can deal with this problem. Their main functions are bypassing the lesions in DNA, replicating the genome and saving the dying cells. This thesis presents a historical review of the literature pertinent to the structure, functions and roles of Y-family DNA polymerases.
DNA Damage ; DNA Repair ; DNA Replication ; DNA-Directed DNA Polymerase ; classification ; metabolism ; physiology ; Humans ; Mutagenesis ; Mutagens ; Proliferating Cell Nuclear Antigen ; genetics

OBJECTIVETo study relation of the expression of hTERT mRNA and cyclin A, p53 protein, proliferation cell nuclear antigen (PCNA) in ameloblastoma (AB) and to investigate clinical biological characteristics of AB.

METHODSThe hTERT mRNA was detected by in situ hybridization, cyclin A, p53 protein and PCNA by SP method. Normal oral mucosa and odontogenic keratocyst (OKC) are comparition.

RESULTSThe positive ratio of hTERT mRNA was 1/7 cases in normal oral mucosa. The expression of cyclin A, p53 and PCNA in normal oral mucosa were similar, and the positive cells distributed in stratum basale. In OKC, the positive cells distributed in stratum basale and super-strrtum basale. And the positive ratio of hTERT, cyclin A, p53, PCNA in OKC was 14/16 cases, 4/32 cases, 11/25 cases, 5/9 cases, respectively. In AB, the positive ratio of hTERT mRNA, cyclin A, p53 protein and PCNA was 94.4% (51/54), 66.7% (40/60), 85.7% (42/49) and 78.1% (25/32), respectively. A strong correlation was found between hTERT mRNA with cyclin A, p53 protein and PCNA (r(s) = 0.914, 0.848, 0.804, P < 0.05).

CONCLUSIONSThe expression of hTETR mRNA, cyclin A, p53 and PCNA is different in different tissues and lesions, and correlates with cell differentiation and clinical biology behaviour. Telomerase activity is related to cumulation of p53 protein, related to cell proliferation and differentiation, regulated by cyclin A, and higher in S phase.

Ameloblastoma ; metabolism ; pathology ; Cyclin A ; biosynthesis ; Humans ; Jaw Neoplasms ; metabolism ; pathology ; Proliferating Cell Nuclear Antigen ; biosynthesis ; RNA, Messenger ; biosynthesis ; Telomerase ; biosynthesis ; genetics ; Tumor Suppressor Protein p53 ; biosynthesis

Aneuploidy ; Biomarkers, Tumor ; metabolism ; DNA, Neoplasm ; genetics ; Humans ; Laryngeal Neoplasms ; metabolism ; pathology ; Lymphatic Metastasis ; Nucleolus Organizer Region ; metabolism ; Proliferating Cell Nuclear Antigen ; metabolism ; S Phase

To better understand the relationship between specific chromosome changes found in human lung tumors and their phenotypic consequences a the tissue level, an in situ hybridization (ISH) procedure of chromosome 17 and immunohistochemistry of proliferating cell nuclear antigen (PCNA) were done. The deparaffinized sections were stained with pericentromeric probes for chromosome 17 and an immunohistochemical study of a monoclonal antibody against PCNA were performed. The numbers of chromosome signals were than compared with the positivity of PCNA expression. The mean numbers of chromosome were 1.62 in normal lymphocytes and 2.48 in lung cancer cells. Tumors showed a high mean positivity of PCNA of 43.4%. Mean PCNA expression was higher in squamous carcinomas than in adenocarcinomas (p<0.05). A linear correlation between numbers of ISH signals and PCNA expression was not demonstrated, but there was a tendency of increasing PCNA positivity according to increasing numbers of ISH signals in adenocarcinomas of the lung and the tumor tissues which were over 50% positive PCNA expression. There was no linear correlation between numbers of ISH signals, PCNA positivity and tumor stages, and keratinization of squamous cell lung cancer. These results suggest that ISH will prove to bo an important tool for determining the underlying genetic basis for tissue phenotypic heterogeneity by allowing genetic determinations to be made on paraffin-embedded tissue sections where histologic architecture is preserved, and immunohistochemical nuclear staining with anti-PCNA on routinely processed tissue is a simple technique for the assessment of proliferation in non-small cell lung carcinoma.
Antigens, Neoplasm/analysis ; Cell Differentiation/physiology ; Cell Division/physiology ; Chromosome Aberrations/*physiology ; *Chromosomes, Human, Pair 17 ; Humans ; Immunohistochemistry ; In Situ Hybridization ; Lung Neoplasms/*genetics/pathology ; Neoplasm Staging ; Nuclear Proteins/analysis ; Phenotype ; Proliferating Cell Nuclear Antigen

OBJECTIVETo construct a plasmid vector expressing the short hairpin RNA (shRNA) targeting proliferation cell nuclear antigen (PCNA), and to investigate its effect in vitro on the expression of PCNA, proliferation and apoptosis of human osteosarcoma cells.

METHODSA plasmid vector expressing the short hairpin RNA targeting at PCNA was constructed and transfected into human osteosarcoma cell line MG-63 by dosper liposomal method. PCNA mRNA and protein expressions were examined using RT-PCR and immunohistochemical staining, respectively. Inhibition of the cell proliferation was studied by MTT method and colony forming assay. DNA synthesis was analyzed by (3)H-TdR incorporation and the cell cycle was determined by flow cytometry. The apoptotic cells were stained with acridine orange.

RESULTSExpression of PCNA mRNA after the transfection was markedly inhibited by 80.51% with a PI value of 25.68% of that of the control group. PCNA shRNA inhibited MG-63 cell growth detected by using MTT method, with an inhibition rate of 61.78% at 48 h. DNA synthesis rate also decreased in the (3)H-TdR incorporation test. Flow cytometry analysis showed an increase of the percentage of G(0)/G(1) phase cells, along with a decrease of cell population in the S phase. The apoptosis rate of cells transfected with the plasmid vector was 16.54%.

CONCLUSIONSPCNA shRNA significantly suppresses the expression of PCNA at both mRNA and protein levels, corresponding to an inhibition of the proliferation of MG-63 cell and an increase of the cellular apoptosis.

Apoptosis ; Bone Neoplasms ; metabolism ; pathology ; Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; Genetic Vectors ; Humans ; Osteosarcoma ; metabolism ; pathology ; Plasmids ; Proliferating Cell Nuclear Antigen ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; RNA, Small Interfering ; biosynthesis ; genetics ; Transfection