No abstract

Lgr5, an orphan G-protein coupled receptor and Wnt target gene, has been identified as a murine intestinal stem cell marker. To elucidate the role of Lgr5 during each stage of human colorectal tumorigenesis, we immunohistochemically analyzed 17 low-grade, 13 high-grade intraepithelial neoplasias and 30 adenocarcinomas. While there was only sporadic expression of Lgr5 at the crypt base in normal epithelia, the increased numbers of Lgr5-positive cells were found in most tumors, with clustering of the cells to form patches. An apparent difference in their distribution was observed among the different tumorigenesis stages. Lgr5 expression in luminal surface showed a negative association with the progressive grade of the tumors (p = 0.0004), while that in the lower crypt exhibited a positive association with grade (p = 0.0001). In adenocarcinomas, Lgr5 expression in the luminal surface was negatively associated with the pStage (p = 0.02), while it was almost invariably high in the lower crypt during advanced pStage disease. These results suggest that increases in putative stem cells with the Lgr5 expression occur early during colorectal tumorigenesis and that the shifts in their distribution towards the crypt base and/or invasive tumor front play a role in the development and progression of colorectal cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 5201. doi:10.1158/1538-7445.AM2011-5201

Isothermal vapor-liquid equilibria were measured for the ternary system methanol + ethanol + water and its constituent binary systems of methanol + water and ethanol + water at 323.15, 328.15, and 333.15 K. The apparatus that was used made it possible to control the measured temperature and total pressure by computer. The experimental binary data were correlated by the NRTL equation. The ternary system was predicted using the binary NRTL parameters with good accuracy.