IKZF1 and plasma cell myeloma: When thalidomide binds to CRBN, CRBN can target multiple neosubstrates, such as casein kinase 1 alpha (CK1α, a CK1 protein that regulates cell cycle signaling/apoptosis) or Ikaros (lymphoid transcription factor essential of myeloma cell survival), which allows for inhibition of angiogenesis and suppression of cellular proliferation [58].