BRAF and melanoma: Prompted by the previous findings demonstrating the role of the enzymes regulating sphingosine-1-phosphate (S1P) and ceramide metabolism as mediators of chemoresistance in colon cancer [10,11,12] and based on an earlier observation from the study in BRAFV600E mutated melanoma which revealed altered ceramide/S1P ratio in vemurafenib-resistant cells [13], we sought to investigate the possible involvement of the key regulators of S1P and ceramide turnover and signalling in acquired resistance to vemurafenib in BRAF mutated colon cancer cells.