Upregulation of interleukin-1 by Epstein-Barr virus latent membrane protein 1 and its possible role in nasopharyngeal carcinoma cell growth.
BACKGROUND
Nasopharyngeal carcinoma (NPC) is associated with Epstein-Barr virus (EBV) infection. We previously found that interleukin (IL)-1alpha and IL-1beta significantly increased in NPC tissues. This study investigated what EBV-encoded proteins were involved in such IL-1 production.


RESULTS
IL-1alpha and IL-1beta messenger ribonucleic acids (mRNAs) were detected in the EBV latent membrane protein 1 (LMP1) transfectant (LMP135) only by reverse transcriptase-polymerase chain reaction (RT-PCR). LMP1-mediated IL-1alpha and IL-1beta production could be enhanced by tumor necrosis factor alpha (TNF-alpha), determined by enzyme-linked immunosorbent assay (ELISA). Moreover, IL-1alpha and IL-1beta mRNAs and proteins were increased in a dose-dependent manner in epithelial cells transiently transfected by an LMP1 plasmid. Besides, immortalized human epidermal keratinocyte (RHEK-1) epithelial cells could be enhanced to proliferate by IL-1alpha and IL-1beta determined by water-soluble tetrazolium salt (WST-1) assay.


CONCLUSIONS
EBV LMP1 is capable of upregulating IL-1alpha and IL-1beta secretions from epithelial cells and positively modulated by TNF-alpha. This may consequently contribute to tumor growth in patients with NPC.
Huang
Yu-Tzu
YT
School of Medicine, Fu Jen Catholic University, Hsin-Chuang, Taipei Hsien, Taiwan, Republic of China.
Liu
Mei-Ying
MY
Tsai
Ching-Hwa
CH
Yeh
Te-Huei
TH
D002277:Carcinoma / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D018929:Cell Culture Techniques; D002460:Cell Line; D049109:Cell Proliferation; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology* / Q000821:virology; D004854:Herpesvirus 4, Human / Q000502:physiology*; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism*; D009303:Nasopharyngeal Neoplasms / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014763:Viral Matrix Proteins / Q000235:genetics / Q000378:metabolism*
C037662:EBV-associated membrane antigen, Epstein-Barr virus; D007375:Interleukin-1; D012333:RNA, Messenger; D014763:Viral Matrix Proteins