PARP-1 expression against Epstein-Barr virus LMP-1 and BZLF-1 in undifferentiated nasopharyngeal carcinoma

Abstract

Objective: This study aims to determine the poly(ADP-ribose) polymerase (PARP)-1 expression levels against the Epstein-Barr virus (EBV) latent membrane protein (LMP-1) and BamHI-Z leftward reading frame (BZLF)-1 of nasopharynx tissues and serum of nasopharyngeal carcinoma (NPC) patients and characterize the histopathology of necrosis cells of NPC tissues. Methods: 32 tissues sections consisting 24 NPC and 12 polyp tissues, and also blood serum of patients were taken from Ulin General Hospital, Banjarmasin. Tissue samples were analyzed by using immunofluorescence staining in order to examine LMP-1 and PARP-1 expression. Analyses were done by using immunoblotting with anti-LMP-1, anti-BZLF-1, anti-PARP-1, and anticaspase-3 antibodies. Histopathological profiles of necrosis cells were analyzed by using hematoxylin-eosin staining and necrotic cells were counted by using the standard software of the microscope. Results: LMP-1, BZLF-1 and PARP-1 proteins have high levels of expression in patients with NPC. LMP-1 expression of NPC patients and control sera are equal. Interestingly we found that 35 kDa of BZLF-1 and 55 kDa PARP-1 only expressed in NPC patients, meanwhile caspase-3 expression was negative. Histopathologically, NPC tissues were more dominated by karyorrhexis than pyknosis and karyolysis. Conclusions: This study showed that the expression level of PARP-1 in NPC tissues was increased against LMP-1 and BZLF-1 EBV to protect DNA damage of the recipient cells. This mechanism probably stimulated cell metamorphosis and consequently provoked necrosis. © 2013 GESDAV