Dataset Information

The stem cell-associated antigen CD133 (Prominin-1) is a molecular therapeutic target for metastatic melanoma.

ABSTRACT: CD133 (Prominin-1) is considered the most important cancer stem cell (CSC)-associated marker identified so far, with increased expression in the CSC fraction of a large variety of human malignancies, including melanoma. Here we investigated the effects of CD133 downregulation in vitro and in vivo in human metastatic melanoma. The average number of CD133 molecules on the cell surface of FEMX-I melanoma cells was decreased by 8.7-fold and 1.8-fold using two different short hairpin RNAs. Downregulation of CD133, confirmed by immunocytochemistry, Western blotting, microarray analysis, and reverse transcription-polymerase chain reaction, resulted in slower cell growth, reduced cell motility, and decreased capacity to form spheroids under stem cell-like growth conditions. Clonal analysis revealed that the reduction in growth rate was proportional to the extent of CD133 downregulation. Monoclonal antibodies directed against two different epitopes of the CD133 protein induced a specific, dose-dependent cytotoxic effect in FEMX-I cells. The downregulation of CD133 severely reduced the capacity of the cells to metastasize, particularly to the spinal cord. In the CD133 downregulated cells, microarray analysis revealed expression changes for only 143 annotated genes (76 up- and 67 downregulated). Ten of the 76 upregulated genes coded for Wnt inhibitors, suggesting an interaction between CD133 and the canonical Wnt pathway. We conclude that CD133, in addition to its role as a CSC marker, is an important therapeutic target for metastatic melanoma and, potentially, for other CD133-expressing cancer types.

SUBMITTER: Rappa G

PROVIDER: S-EPMC2713505 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The stem cell-associated antigen CD133 (Prominin-1) is a molecular therapeutic target for metastatic melanoma.

Rappa Germana G Fodstad Oystein O Lorico Aurelio A

Stem cells (Dayton, Ohio) 20080918 12

CD133 (Prominin-1) is considered the most important cancer stem cell (CSC)-associated marker identified so far, with increased expression in the CSC fraction of a large variety of human malignancies, including melanoma. Here we investigated the effects of CD133 downregulation in vitro and in vivo in human metastatic melanoma. The average number of CD133 molecules on the cell surface of FEMX-I melanoma cells was decreased by 8.7-fold and 1.8-fold using two different short hairpin RNAs. Downregula ...[more]

PMID: 18802032

Similar Datasets

Project description:Exosomes can be viewed as complex "messages" packaged to survive trips to other cells in the local microenvironment and, through body fluids, to distant sites. A large body of evidence indicates a pro-metastatic role for certain types of cancer exosomes. We previously reported that prominin-1 had a pro-metastatic role in melanoma cells and that microvesicles released from metastatic melanoma cells expressed high levels of prominin-1. With the goal to explore the mechanisms that govern proteo-lipidic-microRNA sorting in cancer exosomes and their potential contribution(s) to the metastatic phenotype, we here employed prominin-1-based immunomagnetic separation in combination with filtration and ultracentrifugation to purify prominin-1-expressing exosomes (prom1-exo) from melanoma and colon carcinoma cells. Prom1-exo contained 154 proteins, including all of the 14 proteins most frequently expressed in exosomes, and multiple pro-metastatic proteins, including CD44, MAPK4K, GTP-binding proteins, ADAM10 and Annexin A2. Their lipid composition resembled that of raft microdomains, with a great enrichment in lyso-phosphatidylcholine, lyso-phosphatidyl-ethanolamine and sphingomyelin. The abundance of tetraspanins and of tetraspanin-associated proteins, together with the high levels of sphingomyelin, suggests that proteolipidic assemblies, probably tetraspanin webs, might be the essential structural determinant in the release process of prominin-1 of stem and cancer stem cells. Micro-RNA profiling revealed 49 species of micro-RNA present at higher concentrations in prom1-exo than in parental cells, including 20 with cancer-related function. Extensive accumulation of prom1-exo was observed 3 h after their addition to cultures of melanoma and bone marrow-derived stromal cells (MSC). Short-term co-culture of melanoma cells and MSC resulted in heterologous prominin-1 transfer. Exposure of MSC to prom1-exo increased their invasiveness. Our study supports the concept that specific populations of cancer exosomes contain multiple determinants of the metastatic potential of the cells from which they are derived.

Dataset Information

The stem cell-associated antigen CD133 (Prominin-1) is a molecular therapeutic target for metastatic melanoma.

Publications

The stem cell-associated antigen CD133 (Prominin-1) is a molecular therapeutic target for metastatic melanoma.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets