Expression and Clinical Significance of Heparanasein Osteosarcoma / 대한정형외과학회잡지

PURPOSE: This study examined the expression of heparanase in osteosarcomas and evaluated its prognostic value. MATERIALS AND METHODS: The immunohistochemical expression of heparanase from 51 osteosarcoma tissues was examined, and the correlations between the heparanase expression level and the clinicopathological factors were evaluated. RESULTS: Heparanase over-expression was observed in 37 tissue samples. There was a correlation between the heparanase expression level and a poor chemotherapeutic response, metastasis and poor survival rate. Multivariate analyses revealed that heparanase over-expression was a significant independent risk factor for a distant metastasis of an osteosarcoma. Among the 46 patients who underwent an adequate wide resection, there was a correlation between the heparanase expression level and recurrence. The 5-year survival rate was 83.8% for patients with heparanase negative tumors, and 46.9% for those with heparanase over-expression. Multivariate analysis using the Cox regression model revealed the heparanase expression level to be an independent prognostic indicator. CONCLUSION: These results indicate that heparanase expression might play an important role in local recurrence and metastasis, and might be a biological marker of the prognostic significance in osteosarcoma patients.

Effects of High Amylose Starch on Gut Functions in Rats

This study investigated the effects of high amylose starch (HAS) consumption on gut functions in male Sprague-Dawley rats. Experimental animals were fed an diet containing HAS for 4 weeks (0, 125, 250, 500 g/kg diet). Stool weights, transit time, the pH of cecum, Bifidobacterium growth, short chain fatty acid production, and prostaglandin E2 production in colon mucus were measured. HAS intake did not affect body weight gain or food efficiency ratio during experimental period. There were no significant differences in kidney weight, epididymal fat pad weights or spleen weights, but the weights of the liver and thymus were significantly lower in the HAS100 group. The length of the large intestine, the weights of the cecum wall and cecum contents, and stool weights significantly increased through HAS intake. But transit time was not affected by the experimental diet. Although Bifidobacterium growth in the cecum increased through the HAS intake dose dependently, there were significant differences in the HAS50 and HAS100 groups. HAS intake increased the production of short chain fatty acid in the cecum contents. In particular, acetate and butyrate concentrations grew significantly. And the production of prostaglandin E2 in the colon mucus significantly decreased through HAS intake. These results demonstrate that high amylose starch intake significantly improves gut function.

Effects of Conjugated Linoleic Acid (CLA) on Matrix Metalloproteinase (MMP) Activity and Cell Motility in Human Colon Cancer Cell Lines

Conjugated linoleic acid (CLA) consists of several geometric isomers of linoleic acid. CLA is found in foods derived from ruminants and exhibits strong anticarcinogenic effects in a variety of animal models. Matrix metalloproteinases (MMPs) play a key role in cancer progression. Specifically, MMP-2 and -9, which hydrolyze the basal membrane type IV collagen, are involved in the initial breakdown of collagen and basement membrane components during tumor growth and invasion. However, the effects of CLA on cancer cell motility and MMP expression and activity are not currently well known. Therefore, the present study examined whether CLA reduces the activity of MMP and cell motility in SW480 and SW620 cells, the human colon cancer cell lines. Gelatin zymography and Western blot analysis revealed that phorbol 12-myristate 13-acetate (PMA) induced the activity and protein expression of Mr 92,000 MMP-9 in both cell lines. To examine whether CLA inhibits the MMP activity, cells were incubated with 100 ngfmL PMA in the presence of various concentrations of CLA. PMA-induced MMP-9 activity was decreased by 20 micrometer CLA in SW480 cells, and by 10 micrometer and 20 micrometer CLA in SW620 cells. Results from the Hoyden chamber assay showed that cell motility was increased by PMA and that PMA-induced cell motility was significantly decreased by 20 micrometer CLA in SW480 cells. These results indicate that CLA may reduce the motility and MMP activity in human colon cancer cells.