Objective To know the abnormal expression of the cell cycle-regulated proteins in pancreatic adenocarcinoma and their effect on tumor cell growth. Methods The expression of p16, p21, Rb and p53 protein in 47 cases were investigated by immunohistochemistry with wet autoclave pretreatment for antigen retriaval. Furthermore, tumor growth index were assessed by a novel anti-ki-67 antibody (ki-s5). Results All the expression of p53, p16, p21 and Rb protein were the nuclear stainning. The positive rates of p53, p16, p21 and Rb protein were 55%, 53%, 74% and 98% respectively. There was negative correlation between of p16, p21 or Rb protein expression and ki-67 growth index. No relation of p53 protein stainning and the expression of p21 protein was found. Conclusion In pancreatic adenocarcinoma, the negative expression of p16 protein and p21 protein may play an important role in tumor cell growth, but tumor proliferation caused by abnormality of Rb protein is rare. The expression of p21 protein was not associated with the expression of p53 protein.
ObjectiveTo explore the influence of different radiation doses of 125Ⅰseed on human poorly differentiated gastric cancer cells (BGC823). MethodsSixty four male nude mice of BLAB nu/nu inoculated with human poorly differentiated gastric cancer cells (BGC823) were took as animal models. When tumors of nude mice grew to 0.7-1.2 cm, the nude mice were randomly divided into blank control group, low dose group, middle dose group, and high dose group (n=16). The tumors of nude mice in blank control group were implanted with blank seed, but tumors of nude mice in low dose group, middle dose group, and high dose group were implanted with 125Ⅰseed (the radiation doses of 3 groups were 1.48×10-7 Bq, 2.22×10-7 Bq, and 2.96×10-7 Bq respectively). Four nude mice of 4 groups were randomly collected to measure the tumor volume and weight before implantation, and on 7, 14, 21, and 28 days after implantation, but apoptosis rates and expression levels of cyclinE mRNA were measured on 14 days and 28 days after implantation, by using flow cytometer and semi quantitative RT-PCR method respectively. Results①Except for the blank control group, the tumor volume and weight decreased over time in low dose group, middle dose group, and high dose group. The tumor volume and weight in blank control group were higher than those of other 3 groups on 7, 14, 21, and 28 days after implantation (P < 0.05);in addition, on 28 days after implantation, tumor volume and weight in low dose group were lower than those of middle dose group and high dose group (P < 0.05).②On 14 days and 28 days after implantation, the apoptosis rates of blank control group were lower than those of other 3 groups (P < 0.05), but expression levels of cyclinE mRNA were all higher than those of other 3 groups (P < 0.05). In addition, on 28 days after implantation, apoptosis rate of low dose group was higher than both of middle dose group and high dose group (P < 0.05), but expression level of cyclinE mRNA was lower (P < 0.05). Compared with 14 days in the same group, except for the blank control group (P > 0.05), the apoptosis rates in other 3 groups on 28 days were higher (P < 0.05), with the lower expression levels of cyclinE mRNA (P < 0.05). Conclusions125Ⅰseed in organizational implantation can effectively inhibit the expression of cyclinE mRNA and the growth of human poorly differentiated gastric cancer tissue. Compared with doses of 2.22×10-7 Bq and 2.96×10-7 Bq of 125Ⅰ, low dose (1.48×10-7 Bq) contributes to the apoptosis of human poorly differentiated gastric cancer cells (BGC823).
For research the relationship between the expression of vascular endothelial growth factor (VEGF) and the cell proliferation. The expression of VEGF was evaluated while the cell cycle of hepatoma cell line Hep G2, which was synchronized at G0 phase with serum deprivation, and reinitiated with TPA and blocked with antisense oligonucleotides of c-jun. Results: Hep G2 cell did not express VEGF at G0 phase. TPA could induce the expression of VEGF as well as initiation of cell cycle. The antisense oligonucleotides of c-jun could prohibit the expression of VEGF and arrest the cell cycle at G0 phase. Conclusion: The fact that the expression of VEGF accompanies the initiation of cell cycle suggests that they be regulated by the same singnal pathway, the expression of VEGF may be a marker indicating the proliferation of hepatoma cells.
ObjectiveTo observe effect of echinococcus cyst fluid on proliferation and cell cycle progression of rat hepatic stellate cells (HSC-T6), and to preliminarily reveal a new mechanisms of pro-fibrogenic effect of alveolar echinococcosis. MethodsHSC-T6 cells were treated with different concentrations (0.00-0.90 mg/mL) of echinococcus cyst fluid. Then, the morphological changes were observed under the inverted microscope, the impacts on proliferation and cell cycle were tested by the CCK-8 assay and flow cytometry respectively. ResultsAfter treated by echinococcus cyst fluids with different concentrations (0.00-0.90 mg/mL) for 24 h, the most cells shrinked fusiform shape with more slender synapses, and the proliferation activities were increased with the concentration of echinococcus cyst fluid increasing when it was higher than 0.05 mg/mL (P<0.05), the proportion of G0/G1 was decreased (P<0.05) and those of S and G2/M were increased (P<0.05) with the concentration of echinococcus cyst fluid increasing. ConclusionsEchinococcus cyst fluid could promote proliferation of HSC-T6 cells in a dose-dependent manner, which might due to its impact on cell cycle progression. Therefore, alveolar echinococcosis might promote hepatic fibrosis through regulating hepatic stellate cells, but further research on detail needs to be done in future.
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)
Objective To review recent studies in molecular biology of gastric cancer. Methods Relevant references were reviewed. Results The development and progression of gastric cancer were correlated with oncogenes, growth factors, cyclins, tumor suppressor genes, cell adhesion molecules and unstability of genes.Conclusion Gastric cancer is related to much mutation of genes.
Objective To investigate the effects of chitosan on the cell cycle of the human fibroblasts and on the Ki-67 antigen expression in vitro and to investigate the mechanism of chitosan preventing the postoperative tissue adhesion. Methods The cultured fibroblasts were treated for 48 hours with 0，0.01，0.1，1.0，10.0 mg/ml of chitosan, respectively;then, the cell cycle of the fibroblasts was measured by the flow cytometry. The cultured fibroblasts were treated for 24 hours with the chitiosan at the above concentrations; then, the Ki-67 antigen in the cell nucleus was detected with the immunohistochemical staining toobserve its expression. Results The growth of the fibroblastswas obviously suppressed by chitosan, especially in the cell morphology. When the concentrations of chitosan were 1.0 mg/ml and 10.0 mg/ml, the percentages of the fibroblasts in the proliferation stage were 32.3%±5.2% and 14.7%±2.9%, respectively,which were significantly smaller than the percentage of the fibroblasts when the concentration of chitosan was 0 mg/ml (the control group) (41.9%±5.8%， P＜0.05). When the concentrations were 0.01 mg/ml and 0.1 mg/ml, the percentages of the fibroblasts in the proliferation stage were 39.0%±6.0% and 35.5%±3.4%, respectively, which were smaller than that of the control, but not significantly different from that of the control (P＞0.05). When the concentrations of chitosan were 0.1 mg/ml,1.0 mg/ml and 10.0 mg/ml, the percentages of the fibroblasts that had the positiveKi-67 antigen were 37.3%±3.4%, 30.5%±6.2% and 17.8%±3.0%，respectively, which were significantly smaller than that of the control (57.6%±8.9%， P＜0.05). When the concentration was 0.01 mg/ml, the percentage of the fibroblasts that had the positive Ki-67 antigen was 54.1%±8.0%, which was smaller than that of the control, but not significantly different from that of the control (P＞0.05). ConclusionChitosan can inhibit the proliferation of the fibroblasts and increase the percentage of the fibroblasts in the quiescent stage, which can be considered as one of the mechanisms that chitosan can prevent the postoperative tissueadhesion.
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 investigate the effect of cholecystectomy on the induction of large intestine cancer and its mechanism. Methods After cholecystectomy, the large intestine neoplasm in mice was induced with dimethylhydrazine(DMH).The histogenesis and growth pattern of large intestine cancer were observed.The Sphase fraction (SPF) of epithelium cells in large intestine mucosa was determined using flow cytometry. Before and after operation, the feces of mice were collected to determine the cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid (DCA) and lithocholic acid (LCA) concentration by highperformance liquid chromatography. Results The average number of large intestine neoplasms per mouse,percentage of large intestine adenomas in examined mice and SPF of experimental group were significantly higher than those of control group (P＜0.05). The fecal LCA concentration in postcholecystectomy was significantly higher than that in precholecystectomy and in sham operation group (P=0.00). Conclusion The large intestine neoplasm of mice induced by DMH is increased and the proliferation of epithelium cell in large intestine mucosa is increased after cholecystectomy. This suggests that cholecystectomy has promoting effect on induction of large intestine neoplasm in mice. The gut may deal with the increased secondary bile acid(LCA) concentration postcholecystectomy.
ObjectiveTo construct DPC4 gene recombinant expression vector and to study the inhibitory effect of DPC4 on the growth of human pancreatic adenocarcinoma cell line (PC3) cells.MethodsDPC4 cDNA was amplified from K562 cell line using RTPCR, and was cloned into the pcDNA3.1 vector to construct a recombinant expression vector plasmid pcDNA3.1DPC4. The recombinant expression plasmid was transferred into PC3 cells by liposome method. After G418 selection, cell cycle and apoptosis were assessed by flow cytometry, then the cell growth rate was estimated by cell count. The cells being not transferred plasmid and transferred pcDNA3.1 plasmid were used as controls.ResultsThe DPC4 gene recombinant expression vector was constructed. Wildtype DPC4 gene attributed to the increase of G1 phase cells and the decrease of S phase cells in PC3 cells,and could inhibit the growth of PC3 cells, the cell growth rates was reduced to 34.3%-41.1% of that of the controls, but cell apoptosis was not observed on all groups. ConclusionWildtype DPC4 gene could inhibit the proliferation of human pancreatic adenocarcinoma cells and could become one of the target genes of pancreas adenocarcinoma gene therapy