CYP2S1 and thyroid cancer: This was supported by a previous study that 12(R)-hydroxy-5(Z),8(Z),10(E),14(Z)-eicosatetraenoic acid [12(R)-HETE], as a metabolite of CYP2S1, could be converted to an endogenous AHR ligand to enhance its transcriptional activity.40 This positive feedback loop will further amplify the BRAFV600E/AHR/CYP2S1 oncogenic signal, strongly promoting malignant progression of BRAFV600E-mutated thyroid cancer cells.