Abstract 1678: Visualization of thymidine kinase 1 on the surface of cancer cell lines: A potential diagnostic marker and therapeutic target

Abstract

Abstract Thymidine Kinase 1(TK1) is a salvage pathway enzyme that has been shown to be elevated in many different cancer types, including breast, prostate, and colon. Previous research in our lab using plasma membrane separation has shown an increase in TK1 levels associated with the plasma membrane of cancer cells when compared to normal lymphocytes. After membrane separation the plasma membrane of normal lymphocytes showed a TK1 activity of 1,012 CPM/mg protein/hr(N=20) whereas those of cancer cells showed: Jurkat 34,096(N=28), Raji 70,195(N=20), HL60 46,217(N=34), and MDA-MB-435 50,359(N=24). In this study we sought to further investigate this association by visualizing the surface staining of fluorescently tagged antibodies to TK1. Using a primary rabbit anti-TK1 antibody and a secondary goat anti-rabbit antibody conjugated with a FITC fluorochrome we were able to stain the cells and identify TK1 bound to the cell surface. Using a fluorescent microscope we were able to visualize the fluorescent staining of TK1 in various cancer cell lines, including: Raji, Jurkat, HL60, MDA-MB-435, H358, and MCF-7. We compared these results to our control of stained normal lymphocytes, which showed significantly greater levels of staining in cancer cells. Our results further confirm the presence of membrane associated TK1, and provide further evidence of TK1's usefulness as a diagnostic marker and potential therapeutic target. 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 1678. doi:10.1158/1538-7445.AM2011-1678