Establishment of a nasopharyngeal carcinoma cell line capable of undergoing lytic Epstein–Barr virus reactivation

Abstract

Epstein-Barr virus (EBV) infects more than 90% of the adult human population. Undifferentiated nasopharyngeal carcinoma (NPC) is common in Southeast Asia, with a particularly high incidence among southern Chinese. The EBV genome can be detected in practically all cancer cells in undifferentiated NPC. The role of EBV in pathogenesis of undifferentiated NPC remains elusive. NPC cell lines are known to be difficult to establish in culture. The EBV+ve NPC cell lines, even if established in culture, rapidly lost their EBV episomes upon prolonged propagation. At present, the C666-1 NPC cell line, which is defective in lytic EBV reactivation, is the only EBV+ve NPC cell line available for NPC and EBV research. The need to establish new and representative NPC cell lines is eminent for NPC and EBV research. In this study, we report the use of the Rho-associated kinase inhibitor (Y-27632) has facilitated the establishment of a new EBV+ve NPC cell line from an earlier established NPC xenograft, C17. The C17 cell line was tumorigenic in immune-deficient mice (NOD/SCID). It retained the EBV episomes and could be induced to undergo productive lytic reactivation of EBV to generate infectious virus particles. The C17 cell line represents a new investigative tool for NPC and EBV studies. The ability of C17 to undergo lytic reactivation is unique and opens up the opportunity to examine regulation of latent and lytic infection of EBV and their contributions to NPC pathogenesis.

Establishment and characterization of new tumor xenografts and cancer cell lines from EBV-positive nasopharyngeal carcinoma

“…Most if not all the reported NPC cell lines except C666-1 4 and C17 16 eventually lost their EBV episomes during in vitro culture 5 , 6 . We next examined whether NPC43 could retain EBV episomes during its propagation.…”

“…The successful establishment of the EBV+ve NPC43 cell line from patient specimen by including ROCK inhibitor (Y-27632) in culture supports the hypothesis that suppression of lytic reactivation of EBV in NPC cells is crucial for EBV+ve cell line establishment, at least in culture condition. Recently, we have also established another EBV+ve cell line from C17 NPC xenograft using a similar approach 16 . C666-1 established from NPC xenograft (X666) has been used extensively in investigations 4 .…”

“…EBV–ve Akata and Namalwa cell lines were kindly provided by Professor Kenzo Takada (Hokkaido University, Japan). The HONE1-EBV, C17 and NP69 cells were established in our laboratory 16 , 37 , 38 . C666-1 and HK1 cell lines were kindly provided by Professor Dolly Huang (Chinese University of Hong Kong) 4 , 39 .…”

Therapeutic evaluation of palbociclib and its compatibility with other chemotherapies for primary and recurrent nasopharyngeal carcinoma

“…Furthermore, the detection of HeLa cell's and HPV18's genomic materials in these cell lines has cast doubt on the cellular origins (7) and has limited the applications of these lines in evaluations of novel therapeutic agents against NPC. To address this limitation, we have established new NPC xenografts and cell lines for in vivo and in vitro investigations, including Xeno32 and Xeno76 (xenografts derived from primary NPC; (8)), Xeno23 and NPC43 (a xenograft and cell line respectively derived from recurrent NPC; (8)) and C17 (NPC cell line derived from a xenograft of metastatic NPC; (9)). Together with the conventional NPC cell line C666-1, these newly established NPC xenografts and cell lines represent a comprehensive panel of preclinical NPC models available to assess chemotherapeutic drug e cacy.…”

mSphere of Influence: 3-D Culture Models Influence Studies on Epstein-Barr Virus Molecular Pathogenesis in the Epithelium

“…This function of LMP1 in lytic reactivation also occurs in oral keratinocytes (17), giving us the confidence that we could rely on conclusions drawn from different ALI systems. In the past year, two additional EBV-infected NPC-derived cell lines (C17 and NPC43) have been established (13,18), and it might be possible to extrapolate ALI-induced reactivation studies to these additional cell lines, as well as nasopharynx-derived organotypic rafts.…”