UPP1 and nicotine dependence: The results showed that UPP1 was significantly correlated with fatty acid biosynthesis, fructose and mannose metabolism, galactose metabolism, glycine, serine and threonine metabolism, Kaposi sarcoma-associated herpesvirus infection, nicotine addiction, pantothenate and CoA biosynthesis, porphyrin metabolism, starch and sucrose metabolism, tyrosine metabolism.