More than 90% of patients with NPC or cervical cancer are positive for EBV or HPV, respectively.5,43 To further confirm the relevance of viral oncoproteins to PERK activity, we subjected clinical tissue samples to immunohistochemistry from 86 patients with primary NPC and 121 patients with cervical carcinoma. The gene discussed is EIF2AK3; the disease is nasopharyngeal carcinoma.