ABCG2 and Miyoshi myopathy: A comparison of the expression of ABC transporters in SP cells with that in the main population cells of human MM cell lines showed that ABCG2 expression was significantly higher in SP cells, except in doxorubicin-resistant RPMI-Dox40 SP cells and SP cells of the KMS-11 cell line, which expressed very high levels of ABCB1 (151).