【Abstract】Objective To investigate the expression of PCNA in gastric cancer and its relationship with telomerase activity of peritoneal washings and peritoneal dissemination, and to compare the efficacy of telomerase activity and cytology of peritoneal washings for prediction of peritoneal metastasis of gastric cancer. MethodsTelomeric repeated amplification protocol (TRAP)enzymelinked immunosorbent assay (ELISA) was performed to measure the telomerase activity of peritoneal washings collected from 60 patients with gastric cancer. Exfoliate cytologic analysis of the corresponding samples was used for comparison.Expression of PCNA was measured with immunohistochemical staining.Their relationship with clinicopathologic features were evaluated. ResultsThe positive rate of telomerase activity in peritoneal washing collected from patients with gastric cancer was 41.7%,which well related to serosal invasion, histology types, depth of infiltration and peritoneal metastasis of gastric cancer. The positive rate of telomerase activity increased with the increased depth of infiltration and serosal involvement areas (P＜0.05).The positive rate of exfoliative cytology was 25.0%, which was obviously high in the group with macroscopic peritoneal metastasis (the group of P1-3). The positive rate of exfoliative cytology also increased with the increased depth of infiltration and serosal involvement areas (P＜0.05). Although the positive rate of telomerase activity in peritoneal washing collected from patients with gastric cancer was not significantly higher than that of exfoliative cytology in general, it was significantly higher than that of exfoliative cytology in the group of pT4, P1-3 and undifferentiated type.The PCNA proliferation index (PI) of positive telomerase activity group was significantly higher than that of negative. The PCNA PI was significantly higher in the group of P1-3 and serosal invasion thanthat of P0 and without serosal invasion. ConclusionTo detect telomerase activity in peritoneal washings and to detect tumor cells by cytologic method are useful to predict subclinical metastasis to the peritoneum in patients with gastric cancer,but telomerase activity is more sensitive than the other one.Telomerase activity is well related to proliferating activity of gastric cancer,which was the very important reason of peritoneal metastasis and serosal invasion.
Objective To investigate proliferating cell nuclear antigen (PCNA) gene expression in retinal pigment epithelium (RPE) cells and inhibition of antisense oligonucleotides(AS-OND) encoding PCNA mRNA to gene expression and proliferation of RPE cells, so as to search for new genetic therapy way for pro1iferative vitreoretinopathy (PVR). Methods (1) Rabbit RPE cells cultured in vitro were detected for PCNA expression by streptoavidin-biotin-enzyme complex (SABC) immunohistochemistry at several times. (2) The liposome-mediated synthetic antisense oligodeoxynucleotides (AS-ODN) and sense oligodeoxynucleotides (S-ODN) encoding PCNA were delivered to the RPE cells at different concentrations, then PCNA expresstion were detected by immunohistochemistry. (3) Exposed to different concentrations of AS-ODN and S-ODN, growth activity and suppressive rate of RPE cells were measured by methyl thiazolyl tetrazolium (MTT) methods. Results (1) PCNA were expressed in RPE cells, culmination in 48 hours of culture. (2) PCNA expression were markedly suppressed in the RPE cells treated with 0.28 and 1.12 μmol/L PCNA AS-ODN. (3) 0.28 μmol/L and 1.12 μmol/L PCNA AS-ODN significantly inhibited proliferative activity of RPE cells in a dose-dependent manner, the arrest rates of cellular growth reached 53% and 81% respectively. Conclusion AS-ODN complementary to PCNA mRNA at some concentration can sequence-specifically suppress PCNA expression in RPE cells and cellular proliferative activity, and show potential application to further experimental study for PVR genetic medication. (Chin J Ocul Fundus Dis, 2002, 18: 231-233)
Objective To observe the inhibitory effects of local co-transfection of tissuetype plasminogen activator(tPA) gene and proliferating cell nuclear antigen antisense oligodeoxynucleotides(PCNA-ASODN) on the intima proliferation and restenosis of autograft artery in rabbits. Methods One hundred and twenty male Zelanian rabbits were randomly divided into four groups(n=30, in each group): control group, PCNA-ASODN group, tPA group and tPA+PCNAASODN group. The left and right external iliac arteries (length 1.0 cm) were transplanted reciprocally. The transplanted arteries were respectively soaked in lipofection, PCNAASODN, pBudCE4.1/tPA and pBudCE4.1/tPA+PCNA-ASODN solution about 15 minutes. The transplanted arteries were sutured with 9-0 sutures soaked in PCNA-ASODN and pBudCE4.1/tPA solution. Each group were divided into five subgroups(n=6, in each subgroup) according to the sacrifice time (3 d, 7 d, 14 d, 28 d and 56 d after operation). On every sacrifice time point, the vascular specimens were harvested. The thrombocyte assembling and thrombus forming lining vessel wall were observed by scanning electron microscope. The pathological morphology of transplanted arteries were observed under microscope(HE). The intimal areas and stenosis ratio(%) of transplanted arteries were calculate and analyzed statistically among groups by computer system. The mRNA expression of tPA gene in transplanted ressel wall was detected with vevere transcriptionPCR(RT-PCR). The number of PCNA positive cells in transplanted vessel wall was counted by SP immunochemisty.Results The mRNA expression of tPA gene in the transplanted vessel wall in tPA and tPA+PCNA-ASODN groups was higher than that of the other two groups(P＜0.01).The number of PCNA positive cells in the transplanted arteries in PCNAASODN, tPA and tPA+PCNAASODN groups were significantly lower than that of control group(P＜0.05，P＜0.01). The intimal areas and degrees of luminal stenosis of PCNAASODN, tPA and tPA+PCNAASODN groups were lower than those of control group(P＜0.05，P＜0.01), and those of tPA＋ PCNA-ASODN group were lower than those of PCNA-ASODN and tPA groups(P＜0.05). Scanning electron microscopy showed that there were a few thrombocytes lining the vessel wall of tPA group and tPA+PCNAASODN group and no thrombus, whereas there were abundant thrombocytes and thrombi lining the vessel wall of the control group. Conclusion Co-transfection of tPA gene and PCNA-ASODN can effectively inhibit the proliferation of VSMC, hyperplasia of intima and restenosis of transplanted artery.
Purpose To observe the expression of proliferating cell nuclear antigen（PCNA）and bcl-2 of cultured human retinal pigment epithelial cells（RPE）． Methods SABC techniques were applied for immunocytochemical staining of cultured RPE with mouse anti-human PCNA monoclonal antibody and rabbit antihuman bcl-2 antibodies． Results 31.2% and 50.6% cultured cells were positive to anti-human PCNA at 24h and 48h after seeding，respectively．The positive staining was mottled in the nucleus．positive staining for bcl was seen in 76%to 90% cells as fine granules scattered within the cytoplasm. Conclusion One half of cultured RPE expressed PCNA，indicating that the cells were in phase S of the cell cycle．Positive staining for bcl-2 appeared in much more RPE cells．These biological markers may be associated with the growth activity of cultured RPE． (Chin J Ocul Fundus Dis,1998,14:26-28)
ObjectiveTo investigate the succession model for hyperthyroidism and thyroid carcinoma secondary to nodular goiter in iodine deficiency area. MethodsA total of 216 specimens of goiter patients from iodine deficiency area were collected in the former 3rd hospital of Norman Bethune Medical College from January 1980 to December 1994. Twentyfour heteroploid samples were selected by the method of Hedley with Flow cytometry (FCM) analysis. Paraffin-embedded tissues from the same position were used to perform immunohistochemical staining for proliferating cell nuclear antigen (PCNA), laminin (LN), factor Ⅷ related antigen (FⅧ-RAg), and p53. The proliferative activity, stroma change, and angiogenesis were observed. ResultsPCNA label index (PCNA-LI) and proliferation index (PI) consistent in 24 heteroploid samples with PCNA staining were significantly higher value. PCNA positive cells were mainly distributed over nonfollicular parenchymatous structures, small follicles, and multilayered structures with large bubbly follicles. Destroyed basement membrane and necrosis were found by LN staining in PCNA positive position with vigorous reproductive capacity. Combining FⅧ-RAg staining with LN staining, interstitial proliferation and angiogenesis were obvious in follicular epithelial cells with vigorous reproductive capacity, providing nutrition and superior environment for them. ConclusionsThe reproduction of thyroid follicular epithelial cells, interstitial proliferation, and angiogenesis are all involved in tuberosis and hyperthyroidism, forming precancerous lesion, which suggest the succession model of goiter in iodine deficiency area.
【Abstract】Objective To investigate the inhibitory effects of flavonoids quercetin on the occurrence and proliferation of experimental mammary carcinoma. Methods DMBA induced mammary carcinoma was produced in rats. Seventy-nine female Sprague-Dawly rats were divided randomly into four groups: DMBA, DMBA with TAM, DMBA with quercetin and control. Chemicals had been administered to group A, group B, group C and group D respectively for 28 weeks. Samples of breasts were collected for light microscope observation and electromicroscope observation. Their expressions of proliferating cell nuclear antigen (PCNA) and the protein product of H-ras were examined by immunohistochemical staining. Results ①Mammary carcinoma incidence of group A(76.2%) was significantly higher than that of group B(40.9%), group C(45.5%) and group D(0%),P＜0.05, and there was no significant difference between group B and group C (P＞0.05), which indicated that quercetin could inhibit the occurrence of mammary carcinoma. ②Mean mammary tumor diameter of group A (2.37cm) was significantly larger than that of group B(1.82cm) and group C(1.71cm), P＜0.05, and there was no significant difference between group B and group C (P＞0.05), which indicated that quercetin could inhibit the growth of experimental mammary carcinoma. ③Immunohistochemical staining of PCNA showed significant difference between group A and group B, group A and group C (P＜0.05), with no significant difference between group B and group C (P＞0.05), which indicated that quercetin could inhibit the proliferation rate of tumor cells. ④Significant difference between group A and group B, group A and group C (P＜0.05), and no significant difference between group B and group C (P＞0.05), were noticed with immunohistochemical staining of H-ras protein product, which indicated that quercetin could inhibit the activity of Hras protein. Conclusion Quercetin could reduce the mammary carcinoma incidence and its degree of growth, and it may be related with its inhibitory effect on the activity of Hras and the proliferation of tumor cell.
Objective To investigate the effect of methylprednisolone on the expression of glial fibrillary acidic protein (GFAP) and proliferating cell nuclear antigen (PCNA) in Müller cells of rats’ retinae injured by laser. Methods Forty SD rats were randomly divided into two groups and inflicted with laser photocoagulation.The rats in treatment group were given methylprednisolone by intraperitoneal injection with a dose of 30 mg/kg for 3 days.At the 3rd,7th,14th,and 28th day after photocoagulation respectively, the eyes were enucleated,fixed and cut into sections.Immunohistochemical examination was used to detect the expression of PCNA and GFAP. Results After photocoagulation the Müller cells expressed PCNA both in the treatment and control group,and the expression of PCNA decreased sharply after 3 days. The expression of PCNA in treatment group was less than that in control group. After photocoagulation the Müller cells also expressed GFAP and the expression of GFAP lasted for at least 28 days ,and the expression of GFAP expression in the treatment group was less than that in the control group. Conclusion Methylprednisolone can reduce the expression of GFAP and PCNA in Müller cells of rats’ retinae injured by laser. (Chin J Ocul Fundus Dis, 2002, 18: 299-301)
Objective To investigate the effect of alltrans retinoic acid (atRA) on proliferative artery disease after heart transplantation. Methods Heterotopic heart transplantation model was established by Ono model with 16 inbred healthy male Wistar rats as donors and 16 SD rats as recipients. The rats were divided into chronic rejection group and atRAtreated group by complete random design, and there were 8 rats in each group. Rats in chronic rejection group were given Cyclosporine A 10 mg/(kg·d) by subcutaneous injection after operation, and those in atRAtreated group were given Cyclosporine A 10 mg/(kg·d) in the same way and atRA 10mg/(kg·d) by gavage. The transplanted hearts of rats were taken out 60 days after the transplantation. HE stain, masson stain and Van Gieson were done to analyze the rejection of transplanted hearts, the degree of vascular stenosis and myocardial fibrosis respectively.Immunohistochemistry was used to test proliferating cell nuclear antigen (PCNA). Results The area of myocardial fibrosis in chronic rejection group was obviously larger than that in atRAtreated group（63.99%±11.91% vs.34.68%±6.34%）, and there was significant difference between two groups（t=8.377，P=0.000）. The index of vascular stenosis in chronic rejection group was higher than that in atRAtreated group（62.86±17.18 vs. 40.10±8.20）. Vascular stenosis in atRAtreated group alleviated significantly, and there was significant difference between two groups（t=3.913, P=0.006）. The PCNA positive cells in chronic rejection group were obviously more than that in atRAtreated group（60.17±17.74 vs. 33.96±8.65）, and there was significant difference between two groups（t=5.387, P≤0.001）. There was a positive correlation between the PCNA positive cell ratio and the index of vascular stenosis（r=0.854, P=0.007）. Conclusion Alltrans retinoic acid can inhibit vascular disease after heart transplantation by cell proliferative pathway.
Objective To examine the expression of proliferating cell nuclear antigen (PCNA) of retinal pigment epithelial (RPE) cells, thus assessing the role of mechanism of contact inhibition playing in the process of experimental retinal detachment and reattachemnt.Methods Retinal detachment was produced in 72 cats by subretinal injection of 0.25% solution of healon through a micropipette three weeks after extracapsular lens extraction and vitrectomy. Some of the detached retinae were reattached 24 hours later. At different time, the cats were killed and eye globes were fixed and embeded in paraffin. Histologic sections were processed for immunohistochemistry examination using an antibody to detect PCNA protein. Labeled RPE cells were identified, and the proliferation was quantified in detached and un-detached retinae of detachment group, and also in reattached retinae of reattachment group. The comparsion of PCNA-labeled RPE cells in different groups were analyzed by ANOVA. Results In detached regions of detachment group, PCNA-expression of RPE cells occured within 24 hours, and reached a maximum after 5-6 days, then gradually declined to barely detectable levels after 20 days. Similar tendency was found in reattached retinae, but the number of PCNA-labeled RPE cells was obviously small. Fewer PCNA-labeled RPE cells were found in regions of un-detached retinae in detachment group. The difference of these three groups was significant.Conclusion Proliferation of RPE cells is induced when they lose contact with neural retina, but inhibited after neural retina reattached to RPE cells. It suggests that the mechanism of contact inhibition plays a role in the proliferative process after retinal detachment and reattachment. (Chin J Ocul Fundus Dis，2003，19：20-23)
ObjectiveTo investigate the expression of vascular endothelial growth factor （VEGF） and proliferating cell nuclear antigen (PCNA) in colorectal cancer and its relationship with metastasis and recurrence. MethodsParaffinembedded specimens from 59 patients with colorectal cancer, 16 patients with adenomas and 12 normal colonic tissues were examined and compared by SP immunohistochemical method. ResultsThe positive rate of VEGF in colorectal cancer were significantly higher than that in adenomas (P＜0.05). The positive rate of VEGF in Dukes A and B stage of colorectal cancer were significantly higher than those in Dukes C and D (P＜0.05). Expression of VEGF in postoperative recurrence group was markedly higher than that in the group with no recurrence (P＜0.05). Proliferative activity expression suggested that the poorer the differentiation, the more PCNA increased in case of lymphnode or hepatic metastasis. The PCNA showed marked difference between postoperative and nonpostoperative recurrences (P＜0.05). Conclusion The expression of VEGF and PCNA is closely related to the invasion and metastasis of tumor during the operation. The increased VEGF and high PCNA implies that there may be some potential metastasis present.