HCRTR2 and liver cancer: Since several years, our group demonstrated that orexin receptor type 1 (OX1R) but not orexin receptor type 2 (OX2R) was expressed in digestive cancer cells including pancreatic, colon, and liver cancers (14) where its activation by orexins induced a mitochondrial apoptosis leading to anti-tumoral impact of orexin/OX1R system (15).