OBJECTIVETo verify the existence and significance of calcium/calmodulin dependent serine protein kinase/inhibitors of differentiation 1 (CASK/Id1) pathway in fibroblasts of human keloid.

METHODSImmunofluorescence laser was used to confirm CASK and Id1 protein expression and localization in fibroblasts of the keloid and normal skin. RT-PCR and Western-blot were adopted to analysis the CASK and Id1 expression and differences between keloid and normal skin fibroblasts. The natural combination of CASK and Id1 protein of keloid fibroblasts was tested by immunoprecipitation.

RESULTSCASK and Id1 protein expression were both found in fibroblast cells of keloid and normal skin under normal circumstances. Most of CASK and Id1 were distributed in the cytoplasm and nucleus of fibroblasts. The results of RT-PCR showed that the expression of CASK mRNA in the keloid group was 0.658 +/- 0.024, which was lower than that in the normal control group (1.076 +/- 0.008, t = 11.159, P < 0.05). The expression of Id1 mRNA was 0.497 +/- 0.014, which was higher than that in the normal control group (0.307 +/- 0.017, t = 15.148, P < 0.05). The results of Western-blot showed that the expression level for CASK protein in the keloid group was 0.057 +/- 0.006, which was lower than that in the normal control group (0.168 +/- 0.012, t = 13.524, P < 0.05); the expression of Id1 protein was 0.812 +/- 0.035, which was higher than that in the normal control group (0.368 +/- 0.031, t = 16.356, P < 0.05). The results of immunoprecipitation showed that Id1 could be detected in the CASK precipitate, while CASK also could be detected in the Id1 precipitate. There was a natural binding of CASK and Id1 in keloid fibroblasts.

CONCLUSIONCASK/Id1 signal pathway may be existed and involved in the proliferation of keloid fibroblasts, which is related with the occurrence of keloid.

Cell Proliferation ; genetics ; Cyclin-Dependent Kinase Inhibitor Proteins ; genetics ; metabolism ; Fibroblasts ; metabolism ; Humans ; Inhibitor of Differentiation Protein 1 ; genetics ; metabolism ; Keloid ; metabolism ; pathology ; RNA, Messenger ; metabolism ; Signal Transduction

OBJECTIVETo investigate the biological function of RIG-G gene by establishing a cell line stably expressing RIG-G protein.

METHODSEctopic RIG-G gene was transfected into U937 cells by using Tet-off expression system. Changes before and after RIG-G expression were detected for cell growth, cell morphology, cell surface antigen and cell cycle regulating proteins.

RESULTSRIG-G protein arrested the cells at G0/G1 phase and inhibited cell growth by increasing the cell cycle inhibitors P21 and P27. As compared to that in control group, the proportion of cells at G0/G1 phase in RIG-G-expressing cell group increased from (43.9 +/- 5.6)% to (63.9 +/- 2.3)% (P < 0.01). The rate of growth inhibition was (68.7 +/- 0.2)%. In addition, an increase in CD11C expression [(61.3 +/- 1.1)% vs. (18.0 +/- 0.4)% (P < 0.01)] and in cells with morphologic features of partial differentiation (smaller cell size, reduced nucleus-cytoplasm ratio, notched nucleus and coarse chromatin) was also observed in RIG-G-expressing cells.

CONCLUSIONSRIG-G has potential abilities to inhibit cell proliferation and promote cell differentiation.

Cell Cycle ; genetics ; Cell Differentiation ; Cell Proliferation ; Cyclin-Dependent Kinase Inhibitor p21 ; genetics ; metabolism ; Cyclin-Dependent Kinase Inhibitor p27 ; genetics ; metabolism ; Humans ; Intracellular Signaling Peptides and Proteins ; genetics ; physiology ; Plasmids ; genetics ; Transfection ; U937 Cells

OBJECTIVETo clarify the role of RhoC in the growth of hepatocellular carcinoma cells and its molecular mechanism, so as to explore the molecular target of tumor cell growth.

METHODSsiRNA-RhoC plasmid was constructed and RhoC gene silencing the cell-line of hepatocellular carcinoma was setup. Cell growth was assessed by MTT assay. AgNORs staining was applied to determine cell proliferation. Plate cell clone test was conducted to examine the capacity of cell clone formation. FACS was adopted to measure the course of cell cycle and semi-quantitative RT-PCR was used to determine the expression of cell cycle proteins. In order to further determine the effect of RhoC expression on cell growth, a RhoC over-expression human hepatocellular cell line was setup by PcDNA3-RhoC plasmid transfection.

RESULTSThe inhibition rate of RhoC was 82.3%. From the fourth day of cell culture, the growth of cells in RNAi group was significantly slower than that in parental Bel7402 and negative control groups (0.41 ± 0.10 vs. 0.73 ± 0.11 and 0.71 ± 0.07 respectively, P < 0.05). AgNORs staining showed that average cell stained particles in RNAi group was significantly lower than that in parental Bel7402 and negative control(1.23 ± 0.35 vs. 3.47 ± 0.93 and 3.17 ± 0.78, P < 0.01). Plate clone formation test showed that clone formation efficiency in the RNAi group was notably lower than that in the control group [(20.33 ± 5.42)% vs. (70.58 ± 10.10)% and (69.83 ± 14.77)%, respectively, P < 0.01]. Cell cycle analysis by FACS showed that G(0)/G(1) cell percentage in the RNAi group was significantly higher than that in the control group [(73.14 ± 5.93)% vs. (57.05 ± 5.97)% and (52.99 ± 4.80)%, P < 0.05]. Compared with Bel7402 and negative control groups, the expression of following growth associated genes was significantly decreased: cyclin D1(0.45 ± 0.21 vs. 1.25 ± 0.24 and 1.12 ± 0.15, respectively, P < 0.05)and CDK4 (0.55 ± 0.08 vs. 1.18 ± 0.32 and 1.10 ± 0.29, respectively, P < 0.05); the following genes were notably increased: p16(1.07 ± 0.23 vs. 0.36 ± 0.12 and 0.35 ± 0.13, respectively, P < 0.01)and p21(0.42 ± 0.12 vs. 0.17 ± 0.06 and 0.19 ± 0.08, respectively, P < 0.05). RhoC was highly expressed in PcDNA3-RhoC transfected hepatocellular cell line. From the third day on of the cell culture, cell growth in PcDNA3-RhoC group was remarkably higher than that in the HL7702 and PcDNA3 groups (0.83 ± 0.10 vs. 0.54 ± 0.11 and 0.58 ± 0.55, respectively, P < 0.05).

CONCLUSIONSRhoC is the key molecule in promoting hepatocellular cell growth, and is a promising target for tumor cell growth controlling.

Carcinoma, Hepatocellular ; genetics ; metabolism ; pathology ; Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase 4 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p21 ; metabolism ; Humans ; Liver Neoplasms ; genetics ; metabolism ; pathology ; Plasmids ; RNA Interference ; RNA, Small Interfering ; genetics ; Transfection ; rho GTP-Binding Proteins ; genetics ; metabolism ; rhoC GTP-Binding Protein

In situ hybridization was applied to locate and detect the expression of p57KIP2 in hydatidiform mole (5 cases of partial hydatidiform mole and 18 cases of complete hydatidiform mole) and normal villi (23 cases). The positive signals of p57KIP2 expression were analyzed by HPIAS-1000 Image-Analysis System. p57KIP2 was highly expressed in normal villi but showed distinct low expression in hydatidiform mole (P < 0.01). Furthermore, the locus of low expression of p57KIP2 accorded with the place where lesion of trophoblast occurred. Detection of p57KIP2 made it possible to study the genetics of hydatidiform mole at the transcriptional level. Low expression of p57KIP2 could be a molecular marker in hydatidiform mole and a target for therapy.
Cyclin-Dependent Kinase Inhibitor p57 ; Cyclin-Dependent Kinases ; antagonists & inhibitors ; Enzyme Inhibitors ; metabolism ; Female ; Genomic Imprinting ; genetics ; Humans ; Hydatidiform Mole ; genetics ; metabolism ; Nuclear Proteins ; biosynthesis ; genetics ; Placenta ; metabolism ; Pregnancy ; RNA, Messenger ; biosynthesis ; genetics ; Uterine Neoplasms ; genetics ; metabolism

OBJECTIVETo investigate the expression of cyclin E mRNA, p21(WAF1) mRNA and p27(KIP1) protein in human ameloblastoma (AB), and to explore the clinical and biological characteristics of AB.

METHODSThe expression of cyclin E mRNA, p21(WAF1) mRNA and p27(KIP1) protein in 54 cases of human AB were detected by in situ hybridization or immunohistochemistry (SP method).

RESULTSThe positive expression rate of cyclin E mRNA in the cytoplasm or cell nucleus of AB was 66.7% (36/54). The expression of cyclin E mRNA increased with AB recurrence and malignant transformation, and the difference of expression among primary AB, recurrent AB, and malignant AB, was statistically significant. The positive expression ratio of cyclin E mRNA in OKC was 50.0% (8/16). The p21(WAF1) mRNA expression in the cytoplasm or cell nucleus of AB decreased, and the positive ratio was 22.6% (12/54) in AB, 37.5% (6/16) in OKC, respectively. The p27(KIP1) protein expression in the cell nucleus of AB was positive in a small number of cases, and the positive rate was 16.7% (9/54) in AB, 6.3% (1/16) in OKC, respectively.

CONCLUSIONSThe genesis and invasion of AB is associated with the cell proliferation and differentiation, and regulated by the higher expression of cyclin E and the lower expression of p21(WAF1) and p27(KIP1).

Adolescent ; Adult ; Aged ; Ameloblastoma ; metabolism ; pathology ; Child ; Cyclin E ; genetics ; metabolism ; Cyclin-Dependent Kinase Inhibitor p21 ; genetics ; metabolism ; Cyclin-Dependent Kinase Inhibitor p27 ; Female ; Humans ; Intracellular Signaling Peptides and Proteins ; genetics ; metabolism ; Jaw Neoplasms ; metabolism ; pathology ; Middle Aged ; Oncogene Proteins ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Young Adult

OBJECTIVETo detect the expression of survivin protein, survivin mRNA, p27 protein, p27 mRNA and PTEN protein in hepatocellular carcinomas (HCC) and their clinical significances.

METHODSTissue microarrays were constructed. The expression of survivin protein, p27 protein and PTEN protein were evaluated by immunohistochemical methods and in expression of survivin mRNA and p27 mRNA were evaluated by in stiu hybridization respectively in tumor tissues from 141 HCC patients, 128 samples of para-carcinoma liver tissues, 97 liver tissues far from the carcinomas and normal liver tissues from non HCC patients. The relationship of survivin, p27 and PTEN were investigated and a prediction model of HCC was constructed.

RESULTSThe expressions of survivin protein (Ridit 95% CI = 0.689+/-0.048, P < 0.01), survivin mRNA (Ridit 95% CI = 0.690+/-0.049, P < 0.01) and p27 protein (Ridit 95% CI = 0.556+/-0.053, P < 0.05) in HCC tissues were significantly increased, while the expression of PTEN protein (Ridit 95% CI = 0.282+/-0.048) in HCC tissues was significantly reduced (P < 0.01).

CONCLUSIONOverexpressions of survivin mRNA and p27 protein and reduced expression of PTEN protein might be a valuable marker to predict the presence of HCC.

Adult ; Aged ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Cyclin-Dependent Kinase Inhibitor p27 ; Female ; Humans ; Inhibitor of Apoptosis Proteins ; Intracellular Signaling Peptides and Proteins ; metabolism ; Liver Neoplasms ; metabolism ; pathology ; Male ; Microtubule-Associated Proteins ; metabolism ; Middle Aged ; PTEN Phosphohydrolase ; metabolism ; RNA, Messenger ; genetics

OBJECTIVETo study the expression of p16 and nm23 genes in salivary gland tumors and the relation of P16 and nm23 proteins with fumorigenesis of salivary gland tumors.

METHODSExpression of P16 and nm23 proteins was examined by SABC immunohistochemical method in 39 cases of paraffin blocks of normal salivary gland tissues and salivary gland tumors.

RESULTSP16 and nm23 protein positive staining were mainly found in the cytoplasm and cytoblast of all salivary gland tissues. Positive rate of P16 protein expression was 76.9% (10/13) and 40.9% (9/22) in benign and malignant salivary gland tumors, respectively. There was significant difference between P16 protein expression of benign and malignant tumors by chi 2 test (P < 0.05). mm23 protein positive staining was found in 84.6% (11/13) and 45.5% (10/22) of benign and malignant tumors respectively. The expression of nm23 protein in benign and malignant tumors was significantly different (P < 0.05). There was no correlation of the expression of P16 and nm23 in salivary gland tumors was found (P > 0.05).

CONCLUSIONp16 and nm23 genes may play an important role in different sides in salivary gland tumorigenesis and the reduce of the expression of p16 and nm23 genes may contribute to the generation of malignant salivary gland tumors.

Adenoma, Pleomorphic ; genetics ; metabolism ; Carcinoma, Mucoepidermoid ; genetics ; metabolism ; Cyclin-Dependent Kinase Inhibitor p16 ; biosynthesis ; genetics ; Humans ; Immunohistochemistry ; NM23 Nucleoside Diphosphate Kinases ; Nucleoside-Diphosphate Kinase ; Protein Biosynthesis ; Proteins ; genetics ; Salivary Gland Neoplasms ; genetics ; metabolism ; Salivary Glands ; metabolism

OBJECTIVESThis study is to investigate the effects of tea polyphenols and tea pigments on cell cycle regulators in rat liver precancerous lesions.

METHODSThe modified Solt-Farber precancerous liver rat model was used. Rats were given water, tea polypheol solution (0.1%) or tea pigment solution (0.1%) throughout the whole experiment (56 days). Cyclin D1, P21(WAF1/CIP1), GADD45 and PCNA protein expression were detected by Western blotting and the RT-PCR method was applied to study the expression of Cdk4.

RESULTSCyclin D1, Cdk4 and PCNA expressions were significantly inhibited, and the expression of P21(WAF1/CIP1) and GADD45 were significantly induced by tea polyphenols and tea pigments treatments.

CONCLUSIONTea polyphenols and tea pigments induced cell cycle arrest and inhibited cell proliferation by regulating cell cycle regulators.

Animals ; Blotting, Western ; Cell Cycle Proteins ; drug effects ; genetics ; metabolism ; Cyclin D1 ; drug effects ; metabolism ; Cyclin-Dependent Kinase 4 ; Cyclin-Dependent Kinase Inhibitor p21 ; Cyclin-Dependent Kinases ; genetics ; Cyclins ; drug effects ; metabolism ; Flavonoids ; Intracellular Signaling Peptides and Proteins ; Liver Neoplasms ; genetics ; metabolism ; pathology ; Male ; Phenols ; pharmacology ; Pigments, Biological ; pharmacology ; Polymers ; pharmacology ; Polyphenols ; Precancerous Conditions ; genetics ; metabolism ; pathology ; Proliferating Cell Nuclear Antigen ; drug effects ; metabolism ; Proteins ; Proto-Oncogene Proteins ; RNA, Messenger ; drug effects ; genetics ; metabolism ; Rats ; Rats, Wistar ; Reverse Transcriptase Polymerase Chain Reaction ; Tea ; chemistry

OBJECTIVECytotoxin-associated protein (CagA) of H. pylori has been confirmed to be closely associated with gastric inflammation and tumorigenesis, but the mechanism behind it is little understood. In this study, we try to determine roles of CagA(+) strain in activating PI3K/Akt1 signaling pathway, and affecting expression of p21(WAF1/CIP1) and p27(KIP1), and also in releasing IL-8 in host cells.

METHODSAkt1 phosphorylation and IL-8 levels of CagA(+) and CagA⁻ strain infected AGS cells were detected by ELISAs. Two quantitative RT-PCRs were established to measure p21(WAF1/CIP1) and p27(KIP1) mRNA levels in the CagA(+) and CagA⁻ strain infected cells. LY294002, an inhibitor of PI3K/Akt pathway, was used to define effect of the pathway in IL-8 release.

RESULTSCagA(+) strain could induce an obvious elevation of Akt1 phosphorylation in the infected AGS cells while CagA? strain failed to do so. The CagA(+) H. pylori strain infected AGS cells showed significant drops both in p21(WAF1/CIP1) and p27(KIP1) mRNA levels, whereas the CagA⁻ H. pylori strain caused a remarkable increase in p21(WAF1/CIP1) mRNA without affecting p27(KIP1) gene transcription in the AGS cells. Both the CagA(+) and CagA⁻ H. pylori strains enabled AGS cells to produce close elevated levels of IL-8, and the LY294002 block resulted in unexpected elevations of IL-8 levels.

CONCLUSIONSCagA can activate PI3K/Akt1 pathway that plays an inhibitory role in IL-8 release in H. pylori infected AGS cells. Activation of PI3K/Akt1 pathway and subsequent negative regulation of p21(WAF1/CIP1) and p27(KIP1) expression might be involved in CagA-associated carcinogenesis.

Antigens, Bacterial ; genetics ; physiology ; Bacterial Proteins ; genetics ; physiology ; Cell Line ; Cyclin-Dependent Kinase Inhibitor p21 ; biosynthesis ; Cyclin-Dependent Kinase Inhibitor p27 ; Gastric Mucosa ; cytology ; enzymology ; microbiology ; Helicobacter pylori ; metabolism ; pathogenicity ; physiology ; Humans ; Interleukin-8 ; secretion ; Intracellular Signaling Peptides and Proteins ; metabolism ; Phosphatidylinositol 3-Kinases ; metabolism ; Phosphorylation ; Proto-Oncogene Proteins c-akt ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Signal Transduction ; Transcription, Genetic ; Virulence

The aim of this study was to investigate the gene expression profiles of acute promyelocytic leukemia (APL) cell line NB4 treated with arsenic trioxide (As2O3) by using cDNA microarray. cDNA probes were prepared through reverse transcription from mRNA of NB4 cells treated with or without arsenic trioxide. The probes were labeled with Cy3 and Cy5 fluorescence dyes individually, hybridized with cDNA microarray representing 201 different human genes, and their fluorescent intensities were scanned. The genes were screened through the analysis of the difference in the gene expression profile. The results showed that after the treatment of arsenic trioxide (2 micromol/L), 6 genes were up-regulated, and 12 genes related to apoptosis and signal transduction were down-regulated. The p21, survivin, cdc2 and Wee1Hu genes may be related to the differentiation and/or apoptosis of NB4 cells induced by As2O3. It is concluded that p21, survivin, cdc2 and Wee1Hu may play an important role in the mechanism underling arsenic trioxide-mediated NB4 cell apoptosis.
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; genetics ; Arsenicals ; pharmacology ; CDC2 Protein Kinase ; Cell Line, Tumor ; Cyclin B ; metabolism ; Cyclin-Dependent Kinase Inhibitor p21 ; metabolism ; Cyclin-Dependent Kinases ; Gene Expression Regulation, Neoplastic ; Humans ; Inhibitor of Apoptosis Proteins ; Leukemia, Promyelocytic, Acute ; pathology ; Microtubule-Associated Proteins ; metabolism ; Oxides ; pharmacology