KRT1 and nasopharyngeal carcinoma: In addition, differentially expressed serum proteins such as keratin 1, serum amyloid A protein (SAA), and heat shock protein (HSP70), which are involved in chemoresistance (cis-Diamminedichloroplatinum) and radio-resistance in NPC, were reported as a potentially useful biomarker in NPC recurrence diagnosis [151,152,153,169,170].