WEE1 and neoplasm: Regorafenib, a multi-kinase inhibitor, inhibits several numbers of protein kinases implicated in tumour growth (KIT, RET, RAF-1, and BRAF p38 MAP kinase), metastasis (PDGFR- and FGFR1), and tumour angiogenesis (VEGFR-1, -2, and -3) [30].