The expression or activation of RSK1/2 appears to be increased in many cancers including lung cancer [63,64], head and neck squamous cell carcinoma (HNSCC) [65], breast cancer [40,66], prostate cancer [67], leukemia [68], melanoma [39,69], multiple myeloma [28], and glioblastoma [58,70]. Here, RPS6KA1 is linked to plasma cell myeloma.