Discovery of a Novel Dual-Target Inhibitor of ERK1 and ERK5 That Induces Regulated Cell Death to Overcome Compensatory Mechanism in Specific Tumor Types

ERK1 and ERK5 are proposed to have pivotal roles in several types of cancer. Under some circumstance, ERK5 may provide a common bypass route, which rescues proliferation upon abrogation of ERK1 signaling. Thus, we accurately classified the tumor types from The Cancer Genome Atlas (TCGA) based on the expression levels of ERK1 and ERK5. We proposed a novel therapeutic strategy to overcome the above-mentioned compensatory mechanism in specific tumor types by co-targeting both ERK1 and ERK5. On the basis of the idea of overcoming ERK5 compensation mechanism, 22ac (ADTL-EI1712) as the first selective dual-target inhibitor of ERK1 and ERK5 was discovered to have potent antitumor effects in vitro and in vivo. Interestingly, this compound was found to induce regulated cell death accompanied by autophagy in MKN-74 cells. Taken together, our results warrant the potential of this dual-target inhibitor as a new candidate drug that conquers compensatory mechanism in certain tumor types.