Cell line studies on the role of MEK kinase in tumour response to cisplatin-based chemotherapy are controversial: in some studies MEK1 inhibited (Hong et al, 1999), in others activated TP53-dependent apoptosis after cisplatin administration; in the latter case the apoptosis was completely blocked by MEK1 inhibitors (Ryan et al, 2000; Wang et al, 2000). The gene discussed is MAP2K1; the disease is neoplasm.