MAP2K5 and cancer: To this end, we selected cell lines available from ATCC that express MEK5 and ERK5 mRNA, according to the Cancer Cell Line Encyclopedia: GCT (UPS/MFH), SJCRH30 (rhabdomyosarcoma), sNF96.2 (malignant peripheral nerve sheath tumor) and SKLMS1 and SKUT1 (leiomyosarcoma).