To clarify the clinical significance of alterations of Ha-ras, p53 and RB gene as well as infection with HPV16,18 in human bladder cancer, we examined the state of Ha-ras, p53 and RB genes, sequences of HPV16/18, and their association with clinicopathological parameters in 39 cases of bladder cancer and 7 cases of normal tissue, using nonisotopic PCR-SSCP and dot blot. The overall incidences of Ha-ras, p53 and RB gene mutation and HPV infection in tumor were 61.5% ,36% ,30.8% and 15.4% , respectively. The HPV positive rate was negatively correlated with clinical stage and pathological classification. Rather, the mutations of Ha-ras and p53 gene were positively correlated with the above clinical parameters. The incidence of Ha-ras gene mutation in recurring tumors was significantly higher than that in primary ones. A negative correlation between HPV infection and p53 mutation was also found. The results suggest that the above molecular events and their interaction play important roles in the development of bladder cancer, and that they wonld be of practical assistance in the prognosis and monitoring of bladder cancer.

Objective To explore the method for differentiation induction of leukemia cells into dendritic cells(DC) by A23187 in vitro. Methods Chronic myeloid leukemia K562 cells were cultured with A23187 or cytokine to induce differentiation and form DC. The morphologic features of cells were observed under inverted microscope, the changes of DC surface marks were determined by flow cytometry and RT-PCR, the ability to stimulate lymphocyte proliferation was tested by MTT colorimetry. Results Under the condition of the does (385 ng/ml) of A23187 for four days, some of K562 cells were found in typical dendritic appearance.The expression of DC markers CD1a,CD83 ,HLA-DR,CD86 and CD80 was 6.65 ±2.70,7.37 ±2.40,6.24 ±4.29, 21.60 ± 3.84, 18.52 ± 4.48 repectively, and increased obviously compared with the negative control group(2.80 ±0.52,1.85 ±0.56,2.25 ±0.47,6.69 ±0.83,9.96 ±3.53). The differences had statistical significance (P < 0.05). K562 cells derived from DC acquired the ability to stimulate lymphocyte proliferation.Conclusion A23187 can induce the leukemia cells differenntiation into activated DC-like cells rapidly.

AIM: To investigate whether protein kinase C (PKC) is involved in the proliferation and the telomerase expression in human hepatocellular carcinoma cells. METHODS: Human hepatocellular carcinoma cells (BEL-7402) were treated with exogenous phorbol-12-myristate-13-acetate (PMA, PKC activator) and staurosporine (SP, PKC inhibitor) for 48 hours. The techniques of cell culture and the telomeric repeat amplification protocol silver staining in combination with computer image scanning system in vitro were used to observe the variations of the growth and the telomerase expression. RESULTS: The proliferative potential of BEL-7402 cells was decreased by the action of PMA as well as SP, and the telomerase expression was also inhibited by PMA and SP. CONCLUSION: Our findings suggest that the proliferation of human hepatocellular carcinoma cells and the telomerase expression may be related to PKC. [

Objective To detect the proliferation inhibition and apoptosis of HL-60 cell induced by APS-1 and APS-2 isolated from Polyporus sp. M05 and to investigate its mechanism. Methods The proliferation inhibition was detected by living cells count method,and chosed proper concentration.Flow cytometry with propidium iodide staining was used to detect cell apoptosis. Semi-quantitative RT-PCR was used to detect the expression of apoptosis related gene. Results APS-1 and APS-2 could significantly inhibit the proliferation of HL-60 cells on a time and dose dependent manner. Apoptosis ratio increased to 47. 9% and 26. 8% after HL-60 cells were exposed to APS-1 and APS-2 respectively for 48 h,and the differences had statistical significance (P <0.01). After being induced by APS-1,mRNA of Bax,Fas,Caspase-3 was upregulated. And after being induced by APS-2,mRNA of Bax,Caspase-3 was upregulated,while Fas mRNA did not change. Conclusion APS-1 and APS-2 can inhibit the proliferation and induce apoptosis of HL-60 cells. Mechanism of HL-60 cell apoptosis induced by APS-1 is related to both mitochondrial pathway and Fas signaling pathway,while apoptosis induced by APS-2 is only related to mitochondrial pathway.

Objective To detect the synergetic effect and mechanism of arsenic trioxide(As2O3)and Trichostatin A(TSA)during inducing apoptosis of HL-60 cells.Methods MTT method was used to test the proliferation of HL-60 cells.Cell cycle and apoptosis were detected by FCM.Semi-quantitative RT-PCR was used to detect the mRNA expression of Bax and Bcl-2 in the cells treated by As2O3 and(or)TSA.Results As2O3 combined with TSA could inhibit proliferation and induce cell cycle arrest at G0 and G1.The percent of apoptosis induced by combination of As2O3 and TSA was obviously higher than that of either As2O3 or TSA.Bax gene expression was increased,while Bcl-2 gene expression was decreased,Bax/Bel-2 ratio was up-regulated.Conclusion Synergetic effect by As2O3 and TSA is remarkable in inducing apoptosis of HL-60 cells.Cell cycte arrest and Bax/Bcl-2 ratio play an important role in apoptosis of HL-60 cells induced by As2O3,TSA or their combination.

Objective To study effect and mechanism of fungus polysaccharide PSM-a of Polyporus sp.M05 on S180 bearing mice. Methods MTT method was used to detect the inhibiting role of PSM-a on S180 cells proliferation in vitro. S180 mice model was established,and was administered by gavage. Tumor volume was detected, and the ratio of tumor to mile weight and inhibiting tumor rate. The activity of NK and LAK cells on the target cells was analyzed by MTT colorimetric assay ;HE stain was used to detect the necrosis of tumor cells. Results PSM-a could inhibit S180 cells grouth in vitro. PSM-a could decrease the tumor weight and increase the ratio of tumor volume and mice weight; Tumor inhibiting rate reached 80% and above when treated with 250 μg/nml PSM-a. PSM-a could increase the activity of NK and LAK cells, and necrosis happened. Conclusion PSM-a could significantly inhibit the growth of S180 cells, and the mechanism bnay be related with the increased killing activity of immunne cells to tumor cells.

Objective To investigate the effect of TGF-β1/SMAD signaling pathway on K562 cells growth inhibition caused by HMBA. Methods After establishing the in vitro differentiation model with HMBA on K562 cells, the MTT assay was used to detect the proliferation of K562 cells, the cell cycle profile was detected by flow cytometry, and the mRNA expression of TGF-β1, SMAD3, SMAD4 and EVI1 was measured by RT-PCR assay. Results HMBA could inhibit the proliferation and promote the differentiation of K562 cells obviously, which was time and concentration-dependent, and the 72 h corresponding IC50, was about 2 mmol/L. Within 72 h, flow cytometry assay indicated that the ration of G0-G1 phase cells was up-regulated, and the results of RT-PCR showed that relative mRNA expression of TGF-β1, SMAD3 and SMAD4 at mRNA level was increased gradually while that of EVI1 was decreased gradually. Conclusion HMBA can inhibit K562 cells proliferation through TGF-β1/SMAD signaling pathway.

Objective To study the molecular regulation mechanism of VEGF in the model of ATRA induced differentiation in HL-60 cells,and to provide new targets for leukemia anti-angiogenic therapy.Methods The morphology was observed by Wright-Gimesa staining; HL-60 cells differentiation was detected by NBT reduction experiment.VEGF,STAT3,c-myc mRNAs were measured by reverse transcription-PCR;VEGF,STAT3 and c-myc proteins were determined by Western blot.Results The proliferation of HL-60 cells was inhibited obviously by ATRA(1 μmol/L) with the induction of differentiation,NBT positive rate was 82.59％ (t =-24.157,P ＜ 0.01) ; VEGF mRNA (t =7.339,P ＜ 0.05),STAT3 mRNA (t =3.667,P ＜0.05) and c-myc mRNA (t =6.858,P ＜ 0.05) were all down-regulated.VEGF protein (t =3.386,P ＜0.05),STAT3 protein(t =4.074,P ＜ 0.05) and c-myc protein (t =3.333,P ＜ 0.05) were all down-regulated.Conclusion VEGF expression level is reduced with the procession of differentiation of HL-60 cells,which may be largely correlated with the down regulation of STAT3 and c-myc.

Objective:To study the effects of ICA on HepG2.2.15 cell proliferation, their sensitivity to the lysis by CD3AK effector cell, to investigate the reversal action of ICA on hepatocarcinoma cells from immune escape through Fas/FasL pathway.To provide the theoretical and experimental bases for ICA development.Methods:MTT assay was used to detect cell proliferation and CD3AK cells cytotoxicity activity;flow cytometry assay was used to examine expression of surface molecules and apoptosis rate of HepG2.2.15 cells.Results:When HepG2.2.15 cells line was treated with 50 ?g/ml ICA,a significant reduction of the rate of cell proliferation was observed. Inhibition rate at 48h was 22.04%,and 29.68% at 72h.Kinetic study showed that inhibition of cell proliferation was time dependent (P0.05).ICA could inhibit apoptosis of Jurkat cells induced by HepG2.2.15 cells. In the co-culture system of HepG2.2.15 cell and Jurkat T cell, apoptosis ratio of Jurkat cell was reduced from 46.66% to 18.20% by ICA (P

0.05).Compared with control group,the GK activity of liver cell,the expression of PEPCK and the expression of GLUT4 in model group decreased signifi cantly(P