ORM1 and rheumatoid arthritis: As reported in results section, MRM findings indicate that two specific C-terminal HPT fragments (VGYVSGWGR and VTSIQDWVQK) and two specific A1AG1 fragments (YVGGQEHFAHLLILR and SDVVYTDWK) might be applied as novel biomarkers for the diagnosis and prognosis of RA.