YAP1 and cancer: Activation of the YAP1 transcriptional coactivator has been shown to induce the transcription of multiple cancer-promoting genes in MM cells (Figure 1), including cell cycle promoting genes such as cyclin D1 (CCND1) and forkhead box M1 (FOXM1) [69], connective tissue growth factor (CTGF) [70], and phospholipase-C beta 4 (PLCB4) [71].