Syros scientists conducted a series of preclinical studies of SY-5609 in colorectal cancer cell lines, as well as in 30 independent patient-derived xenograft (PDX) models of colorectal cancer, including BRAF-mutant, KRAS-mutant and wild-type models….Potently inhibited proliferation and induced G2/M cell cycle arrest in KRAS- and BRAF-mutant colorectal cancer cell lines in vitro...Deeper responses, defined as ≥ 90 percent tumor growth inhibition, were observed more frequently in models with BRAF mutations (50 percent, 5/10) relative to KRAS-mutant...