MAP2K1 and cancer: The Ras/Raf/MEK/ERK pathway is one of the critical pathways involved in signal transduction, which results in the control of cell proliferation, survival, and differentiation [16,17] and plays a role in the development of multiple cancers including melanoma, non-small cell lung cancer (NSCLC), etc. MEK1 and MEK2 are closely related and participate in the Ras/Raf/MEK/ERK signal transduction cascade.