Targeting KRAS Mutant CMS3 Subtype by Metabolic Inhibitors

Cancer cells rewire their metabolism in order to boost growth, survival, proliferation, and chemoresistance. The common event of this aberrant metabolism is the increased glucose uptake and fermentation of glucose to lactate. This phenomenon is observed even in the presence of O2 and completely functioning mitochondria. This is known as the “Warburg Effect” and it is a hallmark in cancer. Up to 40% of all CRC’s are known to have a mutated (abnormal) KRAS gene, found at differing frequencies in all consensus molecular subtypes (CMS). CMS3 colon cancer molecular subtype contains the so-called ‘metabolic tumours’ which represents 13% of total CR cases. These tumours display remarkable metabolic deregulation, often showing KRAS mutations (68%). Unfortunately, patients harbouring mutated KRAS are unlikely to benefit from anti-EGFR therapies. Moreover, it remains unclear that patients with KRAS wild-type CRC will definitely respond to such therapies. Although some clinically designed-strategies to modulate KRAS aberrant activation have been designed, all attempts to target KRAS have failed in the clinical assays and KRAS has been assumed to be invulnerable to chemotherapeutic attack. Quest for metabolic inhibitors with anti-tumour activity may constitute a novel and hopeful approach in order to handle KRAS dependent chemoresistance in colon cancer.