BRAF is the most commonly mutated oncogene in melanoma, with the BRAF^V600 mutation occurring in approximately 50% of melanoma patients. The development of therapies, such as Vemurafenib, targeting the BRAF^V600 mutation represents a clear example of successful targeting of an oncogene for the treatment of cancer. However, despite initial profound responses, acquisition of resistance to BRAF inhibitors invariably occurs and represents a major challenge in the clinical management of BRAF^V600 melanoma. Importantly, work from our laboratory and others have now shown that BRAF^V600 regulates aerobic glycolysis in melanoma, and that treatment with Vemurafenib can suppress this glycolytic response. Because glucose metabolism is restored upon development of BRAF inhibitor resistance, these observations highlight the importance of aerobic glycolysis in BRAF-driven melanoma and the need for further investigation of glycolysis as a potential therapeutic target in the treatment of BRAF^V600 melanoma patients.

In order to further explore BRAF-mediated glycolysis we have now performed a whole genome siRNA screen to identify enhancers of BRAF inhibition within the context of viability and glycolysis in BRAF^V600 melanoma cells. For this enhancement screen, WM266.4 cells were transfected with the Dharmacon human genome siRNA library and subsequently treated with either DMSO or Vemurafenib in parallel for 48hrs. Both cell viability and glycolytic responses (as assessed by lactate production per cell) were measured using a multi-parameter imaging and colorimetric screening approach. By mapping this multi-dimensional phenotypic dataset to protein interaction networks we have uncovered novel complexes and pathways that may play a role in coupling aerobic glycolysis to cell survival pathways in the context of BRAF mutant melanoma. Significantly, depletion of components of this network specifically synergise with Vemurafenib to potently suppress glycolysis. These novel regulators of BRAF-driven glycolysis are under further investigation for their potential utility as therapeutic targets in the context of BRAF^V600 mutant melanoma.