Objective
To investigate the effect of exogenous Rb gene on the cell cycle of vitreous retinoblastoma (RB) transplantation tumor in nude mouse.
Methods
Based on establishing vitreous RB transplantation tumor in nude mouse,constructing retrovirus vector of Rb gene PBabe-Rb and transfecing it into the RB transplantation model by liposome Dosper,the change of cell cycle of the RB transplantation tumor by flow cytometry(FCM)was analysed．
Results
FCM showed that the cells of G1phase of the treated eyes were obviously more than the control eyes with the value of DNA index(DI)and S phase fraction(SPF) decreased by the Rb gene expression.
Conclusion
The exogenous PBabe-Rb gene can partially suppress the progress of the cell cycle of RB transplantation tumor in vivo.
(Chin J Ocul Fundus Dis，2000，16：1-70)
In order to investigate the effect of insulin-like growth factor-1 (IGF-1 on the cyclic change of tendon cell, the 6th generation of cultured tendon cell were selected, and 20 ng/ml IGF-1 was added to the medium. After 48 hours, the cells were determined by flow cytometer, as well as the control cells. The results showed that the time of G1 phase, DNA synthesis phase and G2M phase in IGF-1 group were 11.8 hours, 21.4 hours and 6.8 hours respectively, while those were 25.6 hours 22.6 hours and 21.8 hours respectively in the control group. It was showed that the time needed for G1 phase and G2M phase was shortened by IGF-1.
Objective To study the effects of L-arginine （L-Arg） on cell proliferation, inducible nitric oxide synthase (iNOS) expression and cell cycle in human colon carcinoma cell line LS174 through nitric oxide (NO) pathway. Methods LS174 cells were cultured in medium with L-Arg at different concentrations for different times. MTT method was employed to evaluate the level of the cell proliferation. The production of NO in culture supernatants of LS174 cell was detected with enzyme reduction of nitrate. The distribution of the cell cycle was detected with the flow cytometry (FCM). The expression level of iNOS in the cells was determined by Western blot and SP immunocytochemical staining method. Results The growth of LS174 was promoted by the L-Arg at low concentration (0.125 mmol/L) and inhibited at high concentrations (0.5， 2， 8 and 32 mmol/L). The level of NO was increased with the increasing concentration of L-Arg in culture medium. To compare with the control group, the ratio of cells at S phase was increased after 48 hours’ treatments with high concentrations (0.5, 2, 8 and 32 mmol/L) of L-Arg (P＜0.05, P＜0.01); while there was no obvious difference after treatments with low concentration (0.125 mmol/L) of L-Arg (Pgt;0.05). With the increase of the concentration of L-Arg, the expression of iNOS was increased as compared with control group. The higher the concentration of L-Arg was, the better the effect. Conclusion L-Arg can induce the expression of iNOS resulting in increase the production of nitric oxide (NO). Low concentration of L-Arg can promote the growth of LS174 cells, while high concentration ones can inhibit growth and proliferation. The high concentration of L-Arg could induce S phase arrestion in the cell cycle.
Objective To investigate cell cycle as a new tool to evaluate the biocompatibility of biomaterials.Methods The cell cycle and the expression of related genes were analyzed by the methods of immunocytochemistry, protein blotting, RT PCR and flow cytometry. Results The physical properteis, chemical properties and topological properities of biomaterials could not only influence cell cycle of the cells attached onto biomaterials but also affect the expression of related genes of target cells. Conclusion As an important extension of routine proliferation epxeriments, the study of cell cycle control will be great help for us to to study the cell group as an organic society. It revealed the balance between cell proliferation, cell differentiation and apotosis. It is suggested that the study of cell cycle control will play a key role in the research of tissue engineering.
Objective
To investigate the effect on proliferation and apoptosis of vascular endothelial cells exposed to high glucose.
Methods
The cultured human umbilical vein endothelial cells (HUVEC) were treated with high glucose at concentrations of 10,20,30,40,50 mmol/L for 2,4,6,8,10,12,14 days,cpm value was studied by using tritium-labelled thymidine deoxyribose(3H-TdR)incorporation assay.Flow cytometry was used to detect apoptosis index,proliferation index and cell cycle.
Results
Treated with high glucose,the proliferation index and cpm were significantly reduced in a dose and time dependent manner than the control groups(Plt;0.05).The apoptosis index of HUVEC were higher compared with the control groups(Plt;0.05).The percent of the cultured cells in G1 phase in all high glucose groups were increased,the percent in S phase were largely decreased(Plt;0.05).
Conclusion
Exposed to high glucose,the apoptosis of HUVEC was accelerated and the suppressive effect of high glucose on the proliferation of HUVEC was observed.Endothelial cells were possibly arrested in G1/S checkpoint.
(Chin J Ocul Fundus Dis,2000,16:177-180)
Objective
To observe apoptotic and proliferative characteristics of the retinal vascular end othelial cells (RVECs) of the 1～16 weeks diabetic rats and p53 and bcl-2 expressions of the rats,in order to probe the pathogenic mechanism of diabetic retinopathy(DR).
Methods
Models of diabetic Wistar rats were made by alloxan venous injection.The retinal blood vessels were filled by ink,the wholemounts and paraffin-embedded sections of the retinas were made,TUNEL staining and Immunohistochemical ABC staining were used,and light microscopy was taken,in succession.
Results
Apoptosis of the RVECs was not found.Compared with control group,the morphologic features of the RVECs and the structure of the retinal blood vessels remained unchanged.In the period from the 10th to the 16th week,the immunohistochemical stain of PCNA,BrdU,p53,and bcl-2 for RVECs revealed positive results,but there was no any sign of the RVECs stacking and proliferating or new blood vessels forming in the retinas.In control group,the reaction of immunological stain of the aforementioned parameters was negative.
Conclusions
No accelerated apoptosis and proliferation of the RVECs in the 1～16 week diabetic rats happen after alloxan injection.Almost all of the RVECs were stimulated to enter the cell cycle in the 10th week.Expression of p53 and bcl-2 might play an important role in stabilizing the RVECs in early stage of diabetes.
(Chin J Ocul Fundus Dis, 1999, 15: 157-159)
Objective
To evaluate the role of the cell cycle related genes cyclinD1 and Bcl-2 protein expression in the pathogenesis and infilt ration of the uveal melanoma．
Methods
Using immunohis tochemistry to detect the cyclinD1 and bcl-2 protein expression in 96 cases of uveal melanoma．
Results
The expression content of bcl-2 was high in uveal melanoma, and there wasn't any relationship between bcl-2 cell positivity and tumor cell type and extrascleral extension． In contrast, cyclinD1 expression was higher in epithelial cell uveal melanoma than mix cell and spindle cell varieties． There was a positive correlation between cyclinD1 cell positivity and extrascleral
extension．
Conclusion
The expression of bcl-2 protein is important for the survival of the uveal melanoma． CyclinD1 may serve as a sensitive index of its malignancy．
(Chin J Ocul Fundus Dis, 2001,17:44-46)
ObjectiveTo investigate the effects of dipyridamole (DP), one of the human equilibrative nucleoside transporters (hENTs) blockers, on 5-fluorouracil (5-FU) induced cell apoptosis and cell cycle changes of the pancreatic cancer Panc-1 cell line. MethodsPancreatic cancer cell line Panc-1 was divided into hENTs blocked group and hENTs unblocked group. The hENTs blocked group was further divided into two subgroups according to the DP concentration, 5 μmol/L DP group and 10 μmol/L DP group. Each group was incubated in culture medium with or without 1.5×106 ng/L 5-FU for 24 h. Cell apoptosis and cell cycle were detected by flow cytometry. Results①The apoptosis results of each group： Incubated in culture medium with 1.5×106 ng/L 5-FU for 24 h, the apoptosis rates of 5 μmol/L DP group and 10 μmol/L DP group were higer than those of hENTs unblocked group （Plt;0.05）, and which of 10 μmol/L DP group was higer than that of 5 μmol/L DP group (Plt;0.05). Incubated in culture medium without 5-FU for 24 h, there were no significant differences of the apoptosis rates among three groups (Pgt;0.05). ②The cell cycle results of each group: Incubated in culture medium with 1.5×106 ng/L 5-FU for 24 h, the percentages of S phase cells in the 5 μmol/L DP group and 10 μmol/L DP group were less than those of hENTs unblocked group (Plt;0.05). The percentage of S phase cell of 5 μmol/L DP group reduced to 87.09% and that of 10 μmol/L DP group reduced to 74.06% as compared with hENTs unblocked group. 5-FU had little influence on G2 phase (Pgt;0.05) except for the percentage of G2 phase cells in the 5 μmol/L DP group increased significantly (Plt;0.05) as compared with the hENTs unblocked group. Incubated in culture medium without 5-FU for 24 h, there were no significant differences of the cell cycles among three groups (Pgt;0.05). ConclusionsIn pancreatic cancer Panc-1 cell, DP could enhance the cytotoxicity of 5-FU by blocking hENTs. The enhanced cytotoxicity is related to elevation of 5-FU concentration in cells, and unrelated to DP itself.
ObjectiveTo investigate the effect and mechanism of caveolion-1 on the growth and proliferation of human pancreatic carcinoma cell Panc1, in vitro. MethodsThe plasmid pCI-neo-cav-1 and its corresponding empty vector (pCI-neo) were transfected into Panc1 cell line (study group and control group, respectively). Expressions of caveolin-1, Akt, and Aktphosphate (p-Akt) were determined in transfectants by Western blot analysis. The cell growth curve was drawn and the double time was calculated in each group, and the cell cycle was analyzed by flow cytometry. The colony formation ability of tumor cells was detected by anchorageindependent growth assay. ResultsCaveolin-1 expression was up-regulated (Plt;0.01) and the growth of Panc1 cell was inhibited significantly (Plt;0.01) in the study group comparing with the control group. Caveolin-1 overexpression inhibited proliferation of Panc1 cell by arresting the cell cycle in the G0/G1 phase (Plt;0.05), the rate of S phase in the study group was lower than that of the control group (Plt;0.01). Proliferation index of the study group was also lower than that of the control group (Plt;0.01). Caveolin-1 overexpression reduced the capacity of the cells to form colonies in soft agar (Plt;0.01). p-Akt protein was reduced in the study group as compared with the control group (Plt;0.05). ConclusionCaveolin-1 can function as a cancer suppressor through inhibiting the activation of PI3K/Akt signaling pathway in Panc1 cell.
ObjectiveTo study the effects of recombinant human growth hormone (rhGH) on proliferation of human rectal cancer cell in vitro. MethodsThe experiment was divided into control group,rhGH group,Oxaliplatin (LOHP) group and rhGH+LOHP group. The double proliferation time of cells,cell inhibition rate,cell cycle, proliferation index (PI) and DNA inhibition rate of human rectal cancer line,HR8348,were studied by cell culture, MTT assay and flow cytometry on different concentration of rhGH. ResultsIn vitro the markedly accelerated effects of rhGH on multiplication of HR8348 cell line were not found: there was no statistical significance as compared rhGH group with control group or compared rhGH+LOHP group and LOHP group （Pgt;0.05）. The double proliferation time of cells was markedly lengthened, cell inhibition rate and the cells arrested in G0-G1 phase were obviously increased, meanwhile, the cells in S phase （P＜0.05） and G2-M phase and PI were markedly decreased and DNA inhibition rate was obviously risen as compared rhGH+LOHP group with control group or rhGH+LOHP group and rhGH group （P＜0.01）.ConclusionIn vitro rhGH does not accelerate the multiplication of human rectal cancer cells.
