MYC in Cancer: from Undruggable Target to Clinical Trials

MYC is among the most infamous oncogenes in cancer. A notable feature that distinguishes it from other common oncogenes is that its deregulation is not usually due to direct mutation, but instead to its relentless activation by other oncogenic lesions. These signalling pathways funnel through MYC to execute the transcriptional programmes that eventually lead to the uncontrolled proliferation of cancer cells. Indeed, deregulated MYC activity may be linked to most - if not all - human cancers. Despite this unquestionable role of MYC in tumour development and maintenance, no MYC inhibitor has yet been approved for clinical use. The main reason is that MYC has long fallen into the category of 'undruggable' or 'difficult-to-drug' targets, mainly because of its intrinsically disordered structure, which is not amenable to traditional drug development strategies. However, in recent years, attempts to develop MYC inhibitors have multiplied, and the first clinical trials have been testing their efficacy in patients. We are finally reaching the point at which its inhibition seems clinically viable. This Review provides an overview of the various strategies to inhibit MYC, focusing on the most recently described inhibitors and those that have reached clinical trials.