EXPRESSION OF MATRIX METALLOPROTEINASE-7 AND FAS LIGAND: THEIR APOPTOSIS-INDUCING EFFECT ON GASTRIC CANCER CELLS

Objective: To investigate the expression of matrix metalloproteinase-7 (MMP-7) and Fas ligand (FasL) in gastric cancer and explore their role in progression of gastric cancer. Methods: Formalin-fixed paraffin and embedded tissues of primary gastric cancer and adjacent non-tumor mucosa from 113 cases were evaluated for MMP-7, FasL and Capase-3 expression by streptavidin-peroxidase (S-P) immunohistochemistry. The expression of the first two proteins in cancer cells of primary foci was compared with clinicopathological parameters of tumors. We also observed the correlation of MMP-7 and FasL expression with Caspase-3 expression in cancer cells of primary foci. Results: MMP-7 positive immunostaining was less frequently detected in adjacent epithelial cells than in cancer cells of primary foci of gastric cancer (P<0.05, 29.2% vs 69.0%), and so was FasL (P<0.05, 34.5% vs 54.0%). MMP-7 expression was associated with tumor size, Borrmann抯 classification, invasive depth, metastasis and TNM staging (P<0.05), but not with growth pattern, Lauren抯 classification, or histological classification (P>0.05). FasL expression was correlated with tumor size, invasive depth, metastasis, Lauren抯 classification, histological classification (P<0.05), while not with Borrmann抯 classification, TNM staging or growth pattern (P>0.05). Cancer cells of primary foci expressed less Caspase-3 than their adjacent epithelial cells (P<0.05, 32.7% vs 50.4%). There was an obvious correlation between FasL, MMP-7 and Caspase-3 expression in cancer cells of primary foci (P<0.05). Co-expression of MMP-7 and FasL paralleled with Caspase-3 expression in cancer cells of primary foci (P<0.05). Conclusion: MMP-7 and FasL expression was up-regulated in gastric carcinogenesis and was principally involved in progression of gastric cancer. FasL expression could reflect the differentiation of gastric cancer cells and underlie the molecular mechanisms of different pathways of gastric tumorigenesis. Co-expression of MMP-7 and FasL could have apoptosis-inducing effect on gastric cancer cells.

Expression of Matrix Metalloproteinase-7 in Serous Ovarian Tumors

Objective:To explore the expression of matrix metalloproteinase-7 in serous ovarian tumors. Methods: Expression of MMP- 1 in 6 normal ovaries, 12 serous cystadenomas of ovary, 6 borderline cystadenomas of ovary, and 22 serous cystadenocarcinomas of ovary were studied by immunohistoc/temical SP staining. Results: No expression of MMP- 1 was detected in normal ovaries. In most serous ovarian tumors, expression of MMP-7 was detected in both the cytoplasm of tumor cells and stroma, although it was reported in other tumors that MMP- 7 was mainly expressed in the cytoplasm of tumor cells. The expression level of MMP-7 in the cytoplasm of tumor cells was statistically insignificant between serous cystadenomas of ovary, borderline cystadenomas of ovary, and serous cystadenocarcinomas of ovary. But in the stroma, the expression level of MMP-7 in borderline cystadenomas of ovary and serous cystadenocarcinomas of ovary was significantly higher than that in serous cystadenomas of ovary (P<0. 05). In borderline cystadenomas and serous cystadenocarcinomas of ovary, expression of MMP-7 could also be detected in the nuclei of some tumor cells. Conclusion: MMP-7 may play an important role in the progression of serous ovarian tumors.

Prospective study of MMP7 serum levels in the diagnosis of cholangiocarcinoma

AIM: To determine whether the serum level of matrix metalloproteinase-7 (MMP7) has the potential to diagnosis cholangiocarcinoma from benign biliary tract diseases. METHODS: This study was performed according to the PRoBE (a prospective-specimen-collection, retrospectiveblinded-evaluation) design. A total of 187 patients with obstructive jaundice were consecutively enrolled. After the diagnostic status of these patients was ascertained, their levels of serum MMP7 were assayed and compared with serum carbohydrate antigen 19-9 (CA19-9). This was conducted in a blinded case (cholangiocarcinoma)control (benign biliary tract disease) setup. RESULTS: MMP7 and CA19-9 serum levels were significantly elevated in cholangiocarcinoma patients (P < 0.001). The area under the curve (AUC) from a receiver operating characteristic (ROC) curve analysis for thediagnosis of cholangiocarcinoma, using MMP7 was more accurate than CA19-9 (AUC = 0.84, 95% CI: 0.778-0.903 for MMP7 and AUC = 0.79, 95% CI: 0.708-0.868 for CA19-9). The sensitivity and specificity of serum MMP7 (cut-off value of 5.5 ng/mL) was 75% and 78%, respectively, while the sensitivity and specificity of serum CA19-9 (cut-off value of 100 U/mL) was 68% and 87%, respectively. CONCLUSION: Serum values of MMP7 and CA19-9 appear to be useful biomarkers for differentiating cholangiocarcinoma from benign biliary tract obstructive diseases.

Pygopus 2 promotes kidney cancer OS-RC-2 cells proliferation and invasion in vitro and in vivo

Objective:Human Pygopus 2(Pygo2)was recently discovered to be a component of the Wnt signaling pathway required for b-catenin/Tcf-mediated transcription.But the role of Pygo2 in malignant cell proliferation and invasion has not yet been determined.Methods:Lentivirus-mediated small interfering RNA(siRNA)and vector-based overexpression were used to study the function of Pygo2 in OS-RC-2 cells.The resulted cells were subject to Western blotting assay,MTT assay,colony formation and cell invasion assays.Furthermore,renal cell carcinoma(RCC)models were established in BALB/c nude mice inoculated with OS-RC-2 cells.Immunohistochemistry(IHC)staining of matrix metalloproteinase-7(MMP-7),matrix metalloproteinase-9(MMP-9)and vascular endothelial growth factor(VEGF)was performed in tumor tissue.Results:Pygo2 gene was successful knocked down and overexpressed in RCC OS-RC-2 cells by using an shRNA and overexpressing vector,respectively.Overexpression of Pygo2 effectively promoted cell proliferation,colony formation and invasion in vitro.Knockdown of Pygo2 obviously inhibited xenograft tumor growth in nude mice.In addition,overexpression of Pygo2 increased the levels of MMP-7,MMP-9 and VEGF in the xenograft tumors.Conclusion:Pygo2 has a role in promoting cell proliferation,invasion and metastasis,and may regulate angiogenesis via the Wnt/b-catenin signaling pathway.

Effects of Weipixiao(胃痞消)on Wnt Pathway-Associated Proteins in Gastric Mucosal Epithelial Cells from Rats with Gastric Precancerous Lesions*

Objective： To study the effects of Weipixiao （胃痞消, WPX） on Wnt pathway-associated proteins in gastric mucosal epithelial cells from rats with gastric precancerous lesions （GPL）. Methods： Sprague Dawley rats were randomly divided into control, model, vitacoenzyme （0.2 g·kg-l·day-1）, WPX high-dose （H-WPX, 15 g·kg-l·day-1）, WPX medium-dose （M-WPX, 7.5 g·kg-1·day-1） and WPX low-dose （L-WPX, 3.75 g·kg-l·day-1） groups. After successfully establishing the GPL model, the rats were consecutively administered WPX or vitacoenzyme by gastrogavage for 10 weeks. Differential expression of Leucine-rich repeat-containing G-protein- coupled receptor 5 （Lgr5）, matrix metalloproteinase-7 （MMP-7）, Wntl, Wnt3a, and 13 -catenin in gastric mucosal epithelial cells in all groups were immunohistochemically detected, and the images were taken and analyzed semiquantitatively by image pro plus 6.0 software. Results： Gastric epithelium in the model group showed significantly higher expression levels of Lgr5, MMP-7, Wntl, Wnt3a and 13 -catenin than those of the control group （P〈0.01）. Interestingly, we also observed Lgr5＋ cells, which generally located at the base of the gastric glandular unit, migrated to the luminal side of gastric epithelium with GPL. The expression levels of Lgr5, MMP-7, Wntl, and 13-catenin were all down-regulated in the L-WPX group as compared with those of both model and vitacoenzyme groups （P〈0.05）. A similar, but nonsignificant down-regulation in expression level of Wnt3a was noted in all WPX groups （P〉0.05）. Conclusion： Our findings suggested that the therapeutic mechanisms of WPX in treating GPL might be related with its inhibitory effects on the expressions of Lgr5, MMP-7, Wntl, β -catenin and the aberrant activation of Wnt/β -catenin pathway.