When non-cancer hTERT-RPE1 cells were treated for 48 h with metformin, phenformin and VLX600, no toxic effects where observed at the concentrations used for cancer cells, suggesting that these metabolic drugs show higher efficacy in malignant cells and are even more effective in cells with high expression of Kv10.1 (Figure S2a). Here, KCNH1 is linked to cancer.