RPS6KA3 and plasma cell myeloma: Moreover, combination of BI-D1870 with mTOR inhibitor (everolimus) or histone deacetylase inhibitor (MS-275) or BH3-mimic inhibitor for BCL2/BCLXL (ABT-263), resulted in synergistic or additive anti-proliferative effects in myeloma cells suggesting that RSK2 (ser227) is a potential target in treating patients with multiple myeloma [95].