OBJECTIVETo investigate the effect of Oviductus Ranae (OR) on the expressions of CyclinD1, CDK6 and P15 in the liver of aged male rats.

METHODSEighteen male SD rats were randomly divided into 3 equal groups, namely the OR group, VE group and ageing model group. The rats received subcutaneous injection of D-galactose for 6 weeks to establish the aging models, and another 6 rats were injected daily with normal saline (NS) to serve as the normal control group. From the third week of the experiment, the rats were given oral OR or Vitamin E (VE) accordingly till the sixth week. After completion of the drug administration, all the rats were sacrificed for detecting the expressions of CyclinD1, CDK6 and P15 in the liver tissue by Western blotting.

RESULTSThe relative expression levels of CyclinD1, CDK6 and P15 in the liver of the rats in the OR group were 41.73-/+0.54, 23.29-/+0.30 and 1.49-/+0.30, respectively, significantly up-regulated as compared with those in the ageing model group (P<0.01). The expressions of the proteins were obviously down-regulated in the model group in comparison with those in the normal control group.

CONCLUSIONSOR treatment can lower the expressions of Cyclin D1 and CDK6 in the liver to enhance the liver cell proliferation in aged male rats. OR also promotes the expression of P15 through a feedback mechanism to prevent excessive proliferation of the cells. The effect of OR against ageing is mediated possibly by up-regulation of the proteins associated with the cell proliferation in the liver, a mechanism different from that of VE.

Aging ; metabolism ; Animals ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase 6 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p15 ; metabolism ; Liver ; metabolism ; Male ; Materia Medica ; pharmacology ; Rats

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

OBJECTIVETo explore the proliferation and invasive effects of inhibitors of kinase 4(INK4)(P15(ink4b) and P16(ink4a)/CDKN2) gene protein activation on RKO human colorectal cell in vivo and in vitro.

METHODSRKO human colorectal cell line was exposed to the specific DNA methyltransferase inhibitor 5-Aza-CdR and INK4(P15(ink4b) and P16(ink4a)/CDKN2) protein expression was detected by Western blotting. Soft agar cloning experiment and Transwell chamber assay were used to detect the proliferative and invasive ability in vitro. Tumorigenicity in nude mice was analyzed in vivo.

RESULTSINK4(P15(ink4b) and P16(ink4a)/CDKN2) protein expression of RKO human colorectal cells after exposure to 1×10(-7), 5×10(-7) and 1×10(-6) mol/L 5-Aza-CdR concentrations(A, B, C groups) were 1.13, 1.38, 1.92 folds and 1.11, 1.45, 2.14 folds compared to positive control group respectively. Soft agar cloning experiment showed the number of cell colony significantly decreased from 36.8±5.1(positive control group) to 32.4±7.2, 21.3±5.4 and 19.5±6.4 (3 experiment groups, all P<0.05) respectively. Transwell chamber assay showed that migrated cell number in positive control group(67.4±7.2) was significantly higher than those of 3 experimental groups(35.3±4.6, 29.5±7.3 and 25.3±6.2, respectively). The tumor volume of metastasis model in nude mice was inhibited in experimental groups, but not significantly lower compared to control group (P>0.05). There were significant differences of tumor weight and inhibition rate between control group and 3 experimental groups in nude mice respectively(all P<0.01).

CONCLUSIONINK4(P15(ink4b) and P16(ink4a)/CDKN2) protein activation can inhibit tumor proliferation, migration and suppress the tumor formation ability.

Animals ; Cell Line, Tumor ; Cell Proliferation ; Colorectal Neoplasms ; metabolism ; pathology ; Cyclin-Dependent Kinase Inhibitor p15 ; genetics ; metabolism ; Cyclin-Dependent Kinase Inhibitor p16 ; genetics ; metabolism ; Humans ; Mice ; Mice, Inbred BALB C ; Neoplasm Metastasis ; Neoplasm Transplantation ; Transcriptional Activation

OBJECTIVETo study the effects of arsenic trioxide (As(2)O(3)) on cell cycle and expression of cyclin dependent kinase inhibitors (CDKIs) in multiple myeloma (MM) cells, and explore its pharmacological mechanism.

METHODSThe DNA content of MM cells line HS-Sultan was analyzed by flow cytometry after exposure to As(2)O(3), the effects on expression of CDKI P15, P16 AND P21 were studied by reverse transcriptase PCR.

RESULTSDNA flow cytometric analysis showed that As(2)O(3) induced most of HS-Sultan cells, arrest at G(0)/G(1) phase and a small fraction at G(2)/M phase and apoptosis occurred mainly in S phase. There was no expression of P15 and P16 mRNA in untreated HS-Sultan cells and 1.0 micromol/L As(2)O(3) could make them expressed after exposed 24 or 48 hours respectively. Expression of P12 mRNA was obviously elevated by As(2)O(3) comparing with that of control.

CONCLUSIONOne of the pharmacological mechanisms of As(2)O(3) is to activate the expression of CDKI P15, P16 and P21, and consequently affect cell proliferation cycle.

Antineoplastic Agents ; pharmacology ; Arsenicals ; pharmacology ; Cell Cycle ; drug effects ; physiology ; Cyclin-Dependent Kinase Inhibitor p15 ; biosynthesis ; genetics ; Cyclin-Dependent Kinase Inhibitor p16 ; biosynthesis ; genetics ; Cyclin-Dependent Kinase Inhibitor p21 ; biosynthesis ; genetics ; Humans ; Multiple Myeloma ; drug therapy ; metabolism ; pathology ; Oxides ; pharmacology ; RNA, Messenger ; genetics ; Tumor Cells, Cultured

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 effect of monoamine oxidase inhibitor phenelzine on proliferation, apoptosis and histone modulation in acute lymphoblastic leukemia cell line Molt-4 cells.

METHODSThe effect of Phenelzine on cell proliferation was detected by MTT. Apoptotic rate was measured by flow cytometry. The variation of apoptosis associated proteins Caspase-3, Bcl-2 and Bax, cyclin-dependent kinase inhibitor p21, tumor suppressor protein p15, and the expression level of histone methylation of H3K4, H3K9 and histone acetylation of H3, DNMT1 were detected by Western Blot.

RESULTS① Molt-4 cell proliferation rates were (87.68±3.54)%, (67.84±3.24)%, (51.48±3.37)%, (28.72±2.56)% respectively after exposured to phenelzine at 5, 10, 15, 20 μmol/L for 24 h, P<0.05. ② After 10 μmol/L of phenelzine exposure for 24, 48, 72 h, cell proliferation rates were (67.84±3.24)%, (50.24±2.01)%, (40.31±2.25)%, P<0.05. ③ The apoptotic rates were (13.64±2.58)%, (31.24±3.42)%, (56.37±4.26)% after phenelzine treatment at 5, 10, 20 μmol/L for 24 h, which was concentration dependent. ④ Phenelzine could upregulate the expression of Bax, caspase-3, p21, and downregulate Bcl-2 expression. Phenelzine upregulated the methylation level of histone H3K4me1, H3K4me2 and histone acetylated H3, while it didn't change the level of histone H3K4me3, H3K9me1, H3K9me2. ⑤ Phenelzine inhibited DNMT1 expression and promoted p15 expression.

CONCLUSIONSPhenelzine increased the methylation of histone H3K4me1, H3K4me2, acetylation of histone H3 and p21, and decreased the expression of DNMT1 and p15, and ultimately inhibited the proliferation and apoptosis of Molt-4 cells.

Acetylation ; Apoptosis ; drug effects ; Apoptosis Regulatory Proteins ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; Cyclin-Dependent Kinase Inhibitor p15 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p21 ; metabolism ; DNA (Cytosine-5-)-Methyltransferase 1 ; DNA (Cytosine-5-)-Methyltransferases ; metabolism ; Histones ; metabolism ; Humans ; Methylation ; Phenelzine ; pharmacology

OBJECTIVETo investigate the inhibitory effect of transforming growth factor (TGF)-β₁ on oral squamous cell carcinoma (OSCC) Tb cell line.

METHODSCell counting method was used to examine the inhibitory effect of TGF-β₁ on Tb cell and flow cytometry (FCM) assay performed to measure the changes of cell cycle. Superarray was used to screen the changing expression of genes in TGF-β₁/Smads signaling pathway.RT-PCR method was used to detect the results of Superarray.

RESULTSTGF-β₁ showed significant inhibiting effect on OSCC Tb cell line. TGF-β₁ blocked the cell cycle at G₁ phase. The expression level of activin receptor-like kinase-1 (ACVRL-1), anti-mullerian hirmine (AMH), cyclim-dependent kinase inhibitor-2B (CDKN-2B) and transforming growth factor-beta-indnced factor (TGIF) was higer in the cells treated with TGF-β₁ than in control, while TDGF-1 expression was down-regulated. ACVRL-1 and CDKN-2B gene expression was consistent with the results of Superarray.

CONCLUSIONSTGF-β₁ can inhibit the growth of OSCC Tb cell line. The mechanism may be related to the regulation of cell cycle and the expression of ACVRL-1 and CDKN-2B in TGF-β₁-Smads signaling pathway.

Activin Receptors, Type II ; metabolism ; Anti-Mullerian Hormone ; metabolism ; Carcinoma, Squamous Cell ; pathology ; Cell Cycle Checkpoints ; Cell Line, Tumor ; Cyclin-Dependent Kinase Inhibitor p15 ; metabolism ; Humans ; Neoplasm Metastasis ; Signal Transduction ; Transforming Growth Factor beta1 ; pharmacology

OBJECTIVETo detect the presence of p15 antisense RNA(p15AS) in acute myeloid leukemia(AML).

METHODSp15AS and p15 mRNA in two leukemia cell lines was detected with strand-specific primer RT-qPCR. To explore the connection between p15AS and AML, 43 patients with newly diagnosed AML and 21 patients with benign diseases (Iron deficiency anemia) as controls were enrolled. The expression level of p15AS in bone marrow cells derived from the patients and the controls were determined by strand-specific primer RT-qPCR, and its relationship with clinical features was analyzed.

RESULTSThe two AML lines displayed high p15AS and low p15 expression. Samples derived from the AML patients showed relatively increased expression of p15AS and down-regulated p15 expression in their bone cells. In contrast, the 21 controls showed high expression of p15 but relatively low expression of the p15AS. Compared with the normal controls, the expression levels of p15 protein were significantly lower among the AML patients (P<0.01). No relationships were detected between the level of p15AS and the patient's age, gender, FAB subtype, total white blood cell count, platelet count, proliferative degree of bone marrow cell and karyotype classification (P>0.05 for all comparisons).

CONCLUSIONHigh expression of p15 antisense RNA was frequently found among AML patients, and may play an important role in epigenetic silencing of p15.

Adult ; Aged ; Bone Marrow Cells ; metabolism ; Cyclin-Dependent Kinase Inhibitor p15 ; genetics ; Epigenesis, Genetic ; Female ; Gene Expression Regulation, Neoplastic ; Humans ; Leukemia, Myeloid, Acute ; genetics ; metabolism ; Male ; Middle Aged ; RNA, Antisense ; genetics ; metabolism ; Up-Regulation ; Young Adult

BACKGROUND: Aberrant DNA hypermethylation plays a pivotal role in carcinogenesis and disease progression; therefore, accurate measurement of differential gene methylation patterns among many genes is likely to reveal biomarkers for improved risk assessment. We evaluated the gene hypermethylation profiles of primary breast tumors and their corresponding normal tissues and investigated the association between major clinicopathological features and gene hypermethylation. METHODS: A single reaction using methylation-specific multiplex ligation-dependent probe amplification was used to analyze the DNA methylation status of 24 tumor suppressor genes in 60 cancerous tissues and their corresponding normal tissues from patients with primary breast cancer. RESULTS: In cancerous breast tissues, 21 of 24 genes displayed promoter methylation in one or more samples. The most frequently methylated genes included RASSF1 (43.3%), APC (31.7%), CDKN2B (25.0%), CDH13 (23.3%), GSTP1 (16.7%), and BRCA1 (10%). APC was associated with lymph node metastasis, and BRCA1 was associated with negative estrogen receptor and negative progesterone receptor expression. In normal breast tissues, 8 of 24 tumor suppressor genes displayed promoter hypermethylation; CDKN2B (28.3%) and RASSF1 (8.3%) hypermethylation were most frequently observed. CONCLUSIONS: RASSF1 and CDKN2B hypermethylation in Korean breast cancer patients were the most frequent in cancerous tissue and corresponding normal tissue, respectively. Our data indicates that methylation of specific genes is a frequent event in morphologically normal breast tissues adjacent to breast tumors as well as the corresponding breast cancers. This study also suggests that gene methylation is linked to various pathological features of breast cancer; however, this requires confirmation in a larger study.
Adult ; Breast/metabolism ; Breast Neoplasms/*genetics/metabolism/pathology ; Cyclin-Dependent Kinase Inhibitor p15/genetics ; *DNA Methylation ; Female ; Humans ; Lymphatic Metastasis ; Middle Aged ; Promoter Regions, Genetic ; Republic of Korea ; Tumor Suppressor Proteins/genetics

This study was aimed to investigate the regulatory effect of phenylhexyl isothiocyanate (PHI) on methylation of histone H3K4, H3K9 and demethylation of p15 gene in acute leukemia cell line Molt-4, and to explore the possible mechanism inducing re-expression of silent gene. The methylation status of histone H3K4, H3K9 and the expression of P15 protein in the Molt-4 cells treated with PHI were detected by Western blot; the methylation status of p15 gene in the Molt-4 cells before and after treatment with PHI was determined by methylation specific polymerase chain reaction (MSP); the expression level of p15 gene mRNA in Molt-4 cells treated with PHI was assayed by semiquantitative reverse transcription-PCR. The results indicated that the PHI could increase methylation of histone H3K4 and decrease methylation of histone H3K9 in concentration-and time-dependent manners. After treatment of Molt-4 cells with PHI for 5 days, the methylation of p15 gene was reduced, the significant hypermethylation of p15 gene was reversed, the silenced p15 gene re-expressed; the expressions of p15 mRNA and P15 protein were enhanced in concentration-dependent manner. It is concluded that probably through specifically regulating the methylation level of histone H3K4 and H3K9, the PHI causes the changes of chromosome space structure and results in the demethylation of CPG island in p15 gene, thereby induces the re-expression of p15 gene which was silenced.
Cell Line, Tumor ; CpG Islands ; Cyclin-Dependent Kinase Inhibitor p15 ; genetics ; metabolism ; DNA Methylation ; drug effects ; Gene Expression Regulation, Leukemic ; drug effects ; Gene Silencing ; Histones ; genetics ; metabolism ; Humans ; Isothiocyanates ; pharmacology