Abstract 293: Characterization of renal tumor-initiating cells in human renal carcinoma cell lines

Abstract

Abstract High aldehyde dehydrogenase activity (ALDH) has been used as a putative marker for the tumor- initiating subpopulation in many cancer types. We previously showed that tumor-initiating cells in human osteosarcoma OS99-1 cell line can be identified using ALDH. In the current study we sought to determine whether ALDH can be also used as a marker to isolate tumor-initiating populations from human renal carcinoma cell lines. By using a xenograft model in which cells from human renal carcinoma cell line ACHN and Caki-2 were grown in NOD/SCID mice, we identified a subset of renal cells that were highly tumorigenic based on the high aldehyde dehydrogenase activity. Isolated cancer cells with relatively high aldehyde dehydrogenase activity (ALDHbr cells) revealed a greater colony-forming efficiency, higher proliferative output, the ability to grow in non-adhesive spheroids, the capability to undergo adipogenic and osteogenic differentiation, and increased expression of stem cell marker genes Oct3/4A, Nanog and Pax-2. In vivo experiments showed that ALDHbr cells were enriched with greater tumorigenicity compared to their counterparts with low ALDH activity (ALDHlo cells), generating new tumors with as few as 25 cells. The isolation of renal tumor-initiating cells by their high ALDH activity may lead to a new insight into the study of how renal cell carcinoma may take place, and may lead to effective prognostic and therapeutic strategies for the treatment of patients with kidney 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 293. doi:10.1158/1538-7445.AM2011-293