ABCB1 and neoplasm: To further understand whether resistance to chemotherapeutics has been independently associated with increased CD44v6 variant expression that may be associated with a β-catenin/MDR1 pathway, we evaluated stemness in sensitive and FOLFOX resistant (FR) cells of SW480, WIDR and LOVO, by determining their clonogenicity, tumor sphere formation, and their in vivo tumor development by implanting FR and sensitive (S) cells in immunocompromised mice.