1.Rat model of blood-ocular barrier breakdown induced by anterior segment intraocular analogic surgery
Maosong XIE ; Yongzheng ZHENG ; Guoxing XU
Chinese Journal of Ocular Fundus Diseases 2012;28(1):68-72
Objective To establish a rat model of blood ocular barrier breakdown induced by anterior segment intraocular analogic surgery. Methods One hundred and fifty healthy adult male rats were randomly divided into control group and model group,75 rats in each group.The rats were anesthetized with 1 ml/kg ketamine hydrochloride/xylazine hydrochloride solution.Three way pipes were attached to a phosphate buffer infusion bag and two intravenous catheters. One catheter was inserted 30° obliquelythrough the transparent cornea anterior to the limbus into the rat's anterior chamber.Then the needle was withdrawn and the sheath was indwelling.Another catheter was connected with a manometer.Intraocular pressure was varied from 0 to 12 mm Hg (1 mm Hg=0.133 kPa) 60 times,30 times per min.The catheter was removed.The eyes were treated with ofloxacin ophthalmic solution after surgery.The 1st,2nd,3rd,5th and 7th day after surgery,the integrity of the blood ocular barrier was assessed by immunohistochemical staining for albumin and quantitative measurement using Evan's blue as a tracer. Results Albumin immunohistochemical staining of the control group was confined to the iris and retinal blood vessels.The choroid was stained at each time point after surgery.Albumin immunohistochemical staining of the model group was abundant around the iris and the retinal vasculature on the 1st day after surgery.The albumin diffused throughout the iris and the retina on the 2nd and the 3rd day after surgery.The albumin reached the retinal vessels on the 5th and 7th day after surgery.The aqueous humor Evans blue leakages of the model group were higher than those of the control group on the 1st,2nd,3rd and 5th day after surgery.The differences were statistically significant (t=25.781,37.433,25.150,19.171; P<0.01).The Evans blue leakage of the model group was close to that of the control group on the 7th day after surgery. The difference was no statistical significant(t=1.303,P=0.209).The retinal Evans blue leakages of the model group were higher than those of the control group on the 1st,the 2nd and the 3rd day after surgery.The differences were statistically significant (t=11.997,14.622,23.014; P<0.01).The Evans blue leakage of the model group was close to those of the control group on the 5th and 7th day after surgery. The differences were not statistically significant(t=2.027,0.756 ; P=0.058,0.459).Conclusion This study establishes a rat model of blood ocular barrier breakdown induced by imitating the injury to the anterior segment during intraocular surgery.
2.Tissue inhibitor of metalloproteinases 3 promoter methylation and mRNA expression in cardia carcinoma and its relationship with prognosis
Xuefeng XU ; Jiecheng LIN ; Maosong ZHENG ; Chaoqing HUANG ; Yaowu CAI ; Hanxing HUANG
Cancer Research and Clinic 2016;28(12):802-805
Objective To explore the relationship of the methylation levels of tissue inhibitor of metalloproteinases 3 (TIMP-3) gene promoter CpG islands with the invasiveness and prognosis in cardia carcinoma. Methods The tumors tissues were collected from 65 patients with cardia carcinoma. The methylation levels of the promoter of TIMP-3 gene were detected by methylation-specific PCR (MSP), the mRNA expression levels of TIMP-3 gene were detected by RT-PCR. The relationship of TIMP-3 gene ectopic methylation with invasiveness and prognosis of the cardia carcinoma patients was analyzed. Results The positive expression rates of TIMP-3 mRNA in gastric cancer and normal gastric tissues were 53.8 % (35/65) and 96.9 % (63/65), respectively. The difference was not statistically significant(Fisher exact test, P=0.912). The positive rate of TIMP-3 mRNA was negatively correlated with the depth of tumor invasion and lymph node metastasis [mucosa and muscular vs. serosa and mucosa outside of the serosa and muscula: 83.3 % (10/12) vs. 45.3 % (24/53); with lymph node metastasis vs. without lymph node metastasis: 73.9 % (17/23) vs. 40.5 %(17/42)] (both P<0.05). There was a negative correlation between TIMP-3 gene promoter methylation and TIMP-3 mRNA expression (r=-0.276, P=0.026). The size of tumor and TIMP-3 gene promoter methylation were both the independent influencial factors of prognosis in cardia carcinoma (both P<0.05). Conclusion The methylation of promoter region in CpG islands plays an important role in the invasion and metastasis of cardia carcinoma, and it can be used as an independent predictor of biological behavior and prognosis.
3.The promoter methylation of tissue inhibitor of metalloproteinase 3 in cardia carcinoma and its clinical significance
Xuefeng XU ; Jiecheng LIN ; Maosong ZHENG ; Chaoqing HUANG ; Yaowu CAI ; Hanxing HUANG
Cancer Research and Clinic 2016;28(1):36-39
Objective To explore the relations among the promoter methylation of tissue inhibitor of metalloproteinase-3 (TIMP-3) gene and its protein expression, and the clinicopathological features in the gastric cardia carcinoma. Methods The tumor tissues and the adjacent normal mucosal tissues were collected from 65 patients with cardia carcinoma. The promoter methylation levels and the protein expression of TIMP-3 gene were detected by methylation-specific PCR (MSP) and immunohistochemistry respectively. Results The TIMP-3 methylation rates was 78.5 % (51/65) in the tumor tissues and 13.8 % (9/65) in the incisal edge of normal tissues, the methylation rates of TIMP-3 had positive correlation with the size of tumor, invasion depth, lymphatic metastasis and the stage of tumor. The protein expression of TIMP-3 was 26.2 %(17/65) in the tumor tissues and 95.4 % (62/65) in the incisal edge of normal tissues (P = 0.016), the protein expression of TIMP-3 was negatively correlated with the size of tumor, invasion depth, lymphatic metastasis and the stage of tumor. Conclusion The methylation of promoter region in CpG islands is a main mechanism of reduced and loss expression of TIMP-3 gene, which may play an important role in the invasion and metastasis of cardia carcinoma.
4.EZH2-mediated regulation of NF-κB target gene expression in gastric cancer
Xuelei WU ; Yaowu CAI ; Zhizhong ZHUANG ; Yuanjing CHEN ; Renjie GUO ; Maosong ZHENG
Chinese Journal of Pathophysiology 2015;(12):2169-2175
AIM:To explore the mechanism by which over-expression of enhancer of zeste homolog 2 (EZH2) in a panel of gastric cancer cell lines is involved in tumorigenesis of gastric cancer .METHODS: Real-time PCR and Western blot were employed to examine the mRNA and protein levels of EZH 2, respectively.MTS assay, cell migration and soft agar assay were performed to investigate the role of EZH 2 in the regulation of stomach cancer behaviors .The effect of EZH2 on NF-κB target gene expression was determined by Luciferase reporter and real-time PCR.Co-immunoprecipitati-on was used to analyze the interaction of EZH 2 and p65 in HEK293T cells.RESULTS: The expression levels of EZH2 were significantly increased in the gastric cancer cells compared with normal gastric epithelial cells .Pharmacological inhibi-tion by DZNep or knockdown of EZH2 significantly compromised AGS and SNU-16 cell activity , cell migration and anchor-age-independent cell growth.Moreover, siRNA knockdown of EZH2 impaired NF-κB downstream targets, such as IL-8, CXCL5 and CCL20.In addition, the interaction of EZH2 and p65 was detected.CONCLUSION: EZH2 mediates the growth of gastric cancer cells through the regulation of NF-κB downstream gene expression .