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@#AIM: To study the effect of high glucose environment on human corneal epithelial cell injury and repair, and to explain the significance of Cyclin D1 protein expression in corneal epithelial cell wound healing in high glucose culture. <p>METHODS: The high-glucose micro-environment of diabetic corneal lesions was simulated. After human corneal epithelial cells were resuscitated, cultured and passaged, a normal control group of DMEM complete medium of equal volume of distilled water and a high-glucose treated group of DMEM complete medium containing 25mmol/L glucose were set respectively. After the cells were overgrown, the cells were stimulated with scratches. The growth conditions and changes of the cells in each group were observed and compared under an inverted phase contrast microscope. Western glucose was used to analyze high glucose at different time points(0, 12, 24, 48, and 72h)Cyclin D1 Protein expression in cultured corneal epithelial cells. The qRT-PCR was used to analyze high glucose at different time points and each group Cyclin D1 mRNA expression.<p>RESULTS: Under the conditions of high glucose treatment <i>in vitro</i>, the repair rate of human corneal epithelial cells was slowed down after injury, floating cells increased, cells reattached less, and cell spacing increased. With the increase of high glucose treatment time, the cell state became worse and the growth rate slow; normal group repaired cell damage faster, increased cell density, regular morphology, and smooth cell membrane. Cyclin D1 expression was up-regulated by Western blot, but the up-regulation effect gradually weakened with time. The highest expression of Cyclin D1 in both groups appeared at 12h. The expression of Cyclin D1 in the high glucose treatment group was lower than that in the normal control group. The qRT-PCR results showed that after high glucose treatment, the expression of Cyclin D1 mRNA was up-regulated, but with the increase of high glucose treatment time, the up-regulation effect weakened, and the mRNA level recovered to the same level as the control group at 48h. <p>CONCLUSION: In the process of corneal epithelial cell wound healing, high glucose negatively regulates and inhibits the expression of Cyclin D1 protein, and is related to the decline of corneal epithelial cell proliferation and apoptosis.
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Objective:To investigate the effects of ursolic acid on proliferation and apoptosis of hepatic carcinoma cell line HepG2 and its partial mechanism.Methods:The human HepG2 cells were cultured by different concentrations of ursolic acid.The inhibitions of ursolic acid on cell proliferation were determined by using MTT.The effects of ursolic acid on on cell apoptosis and cell cycle were detected by using flow cytometry.The expressions of pERK1/2 and Cyclin D1 proteins after culturing by different concentrations of ursolic acid were tested by using Western blotting.Results:The human hepatoma HepG2 cell proliferations were inhibited by different concentrations of ursolic acid,and the effects showed dose and time-dependent manner(P＜0.05).The cell apoptosis rate for human hepatoma cell line HepG2 was achieved to the maximum under 60 μ mol/L ursolic acid for 72 h,which was (78.723 ± 3.623)％.Ursolic acid could significantly increase the Go/G1 phase cells proportion,and induce HepG2 apoptosis.Ursolic acid could inhibit the expressions of pERK1/2 and Cyclin D1 proteins,and inhibitory effects showed more apparent along with the concentration and time gradually increasing.Conclusion:Ursolic acid could inhibit the proliferation of human hepatic carcinoma HepG2 cell line,block of cells in G0/G1 phase,and promote the cell apoptosis.This might be related with down-regulation of the expressions of pERK1/2 and Cyclin D1 proteins.
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Objective To investigate the expression of p57kip2 and cyclin D1 in human brain glioma and its clinical significance.Methods The expression of p57kip2 and cyclin D1 was detected by SP immunohistochemical technique in brain glioma(n=55) and normal brain tissues(n=10).Results Positive rate of p57kip2 protein in the 55 cases of brain glioma was 38.2%(21/55),significantly lower than that in normal brain tissues(80%,P
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Cyclin D1, a G1 cyclin, has been implicated in the oncogenesis of various types of malignancies via deregulation of cell cycles. Amplification of cyclin D1 as a part of 11q13 amplicon has been reported in lung cancer as well as a subset of carcinomas arising from various organs including breast, head and neck, and esophagus. In addition to its role as an oncogene, several recent studies have suggested that amplification is indicative of poor prognosis. In this study we examined the cyclin D1 protein expression in 102 consecutive cases of lung cancers using the microwave enhanced immunohistochemical staining method and correlated the data with the histologic subtype and grade, Ki-67 (MIB-1) labeling index, and survival. Nuclear positive staining was observed in 18 cases (18 %) of lung cancers. Although squamous cell carcinoma demonstrated a higher rate of expression (12 /58, 21%), three of 33 adenocarcinomas (9%) revealed overexpression and both adenocarcinoma and squamous cell carcinoma components within the adenosquamous carcinoma showed nuclear staining. There was no correlation between cyclin D1 overexpression and histologic grade, Ki-67 (MIB-1) labeling index, and survival. These observations indicate that cyclin D1 protein overexpression might be implicated in the oncogenesis of the various histologic types of non-small cell lung carcinomas but it has no usefulness as a prognostic marker.