(a) Mean standardized uptake value (SUV)

in stage 4 gastric cancer patients was not significantly higher than in stage 2 and stage 3 patients. (b) Mean SUV in intestinal tumors was not significantly greater than in AZD5363 manufacturer non-intestinal tumors. (c) Spearman’s correlation analysis revealed a significant correlation between tumor size and mean SUV (rs = 0.33, P < 0.05). Values are expressed as mean ± SEM. Int; Intestinal Type, Non-Int; Non-intestinal Type, MI-503 supplier SUV; Standardized Uptake Value. These results indicate that SUV was not dependent on the number of lymph node metastases or cancer stage. Maximum tumor diameter was the only parameter with a significant difference. To more precisely determine its correlation with SUV, we carried out quantitative analysis (Figure 1c). Spearman’s correlation analysis indicated a possible relationship between the factors (rs = 0.33, P < 0.05). Expression of glucose transporter and glucose metabolizing enzymes in gastric Nutlin3 cancer GLUT1 staining was seen in the cell walls, while HK2 staining was observed in the cytoplasm, of tubular (Figure 2a1, 2b1) and poorly differentiated (Figure 2a2, 2b2) adenocarcinomas. Based on these results, specimens were evaluated by qRT-PCR to determine the expression of glucose metabolism-related genes (HK1, HK2, GLUT1, and glucose-6-phosphatase

(G6Pase)). MTMR9 HK2 and GLUT1 levels were three-fold higher in cancerous tissue than in normal mucosa (P < 0.001) (Figure 2c). G6Pase is a gluconeogenic enzyme in the liver that reverses the reaction metabolized by HK (glucose to glucose-6-phosphate) [22]. Its expression appeared to decrease in cancerous tissue, but not to a significant degree. In spite of the high levels, no significant correlation was observed between SUV and HK2 (Figure 2d) or GLUT1 (Figure 2e)

expression. The glucose metabolic pathway in cancerous tissues may be too complicated to regulate with the alteration of a single molecule. Figure 2 Expression of glucose transporter and glucose metabolizing enzymes in gastric cancer. (a) Glucose transporter 1 (GLUT1) staining was strong in the cell walls of tubular (a1) and poorly differentiated adenocarcinomas (a2). (b) Staining for hexokinase 2 (HK2) was seen in the cytoplasm of tubular (b1) and poorly differentiated adenocarcinomas (b2). (c) Increased mRNA expression of glucose metabolism-related proteins was observed with HK2 and GLUT1, but not HK1 and Glucose-6-phosphatase (G6Pase). (d-e) Spearman’s correlation analysis found no association between standardized uptake value (SUV) and HK2 (d) or GLUT1 (e) mRNA expression. Values are expressed as mean ± SEM. *P < 0.05. GLUT1; Glucose transporter 1, G6Pase; Glucose-6-phosphatase, HK1; Hexokinase 1, HK2; Hexokinase 2, SUV; Standardized Uptake Value.