Article

Identification of CD15 as a Marker for Tumor-Propagating Cells in a Mouse Model of Medulloblastoma

Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA.
Cancer cell (Impact Factor: 23.89). 03/2009; 15(2):135-47. DOI: 10.1016/j.ccr.2008.12.016
Source: PubMed

ABSTRACT The growth of many cancers depends on self-renewing cells called cancer stem cells or tumor-propagating cells (TPCs). In human brain tumors, cells expressing the stem cell marker CD133 have been implicated as TPCs. Here we show that tumors from a model of medulloblastoma, the Patched mutant mouse, are propagated not by CD133(+) cells but by cells expressing the progenitor markers Math1 and CD15/SSEA-1. These cells have a distinct expression profile that suggests increased proliferative capacity and decreased tendency to undergo apoptosis and differentiation. CD15 is also found in a subset of human medulloblastomas, and tumors expressing genes similar to those found in murine CD15(+) cells have a poorer prognosis. Thus, CD15 may represent an important marker for TPCs in medulloblastoma.

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