MAPK7 and chronic myelogenous leukemia, BCR-ABL1 positive: To name just a few examples, it has been shown that ERK5 positively affects the proliferation of prostate cancer cells in vitro and in vivo [32, 33], regulates the growth of chronic myeloid leukemia (CML)-patient-derived cells [34], and supports the proliferation and survival of multiple myeloma (MM) cells [35].