LZTR1 and neoplasm: Accordingly, LZTR1 has a tumor suppressor phenotype following CRISPR-mediated knockout in KRAS-dependent, but not RAS-independent, MM lines (Fig. 3D), and LZTR1 knockdown amplified KRAS protein expression in KRAS-dependent MM lines (Fig. 3E) via decreased K48-linked ubiquitination of KRAS (Fig. S3D).