RPS6KA3 and hepatocellular carcinoma: Recurrent inactivating mutations in ribosomal protein S6 kinase A3 (RPS6KA3; 9.6%), a gene involved in the rat sarcoma virus (Ras)/rapidly accelerated fibrosarcoma (Raf)/mitogen-activated protein kinase (MAPK) pathway (also called Ras/Raf/MEK/ERK pathway), have also been identified, especially in noncirrhotic HCC.