SOX4 and Miyoshi myopathy: Besides increased overall level of stemness reported recently for Ist-Mes-2 spheres [27], mesospheres derived from all MM cell lines tested showed higher level of various stem cell markers, among which CD24, ABCG2, ABCB5 and OCT4 and also transcription factors SOX4, KLF4 and c-Myc are common to all of them.