[en] Two epithelia tumor cell lines were established from biopsy specimens of nasopharyngeal carcinomas (NPC). The specimens were taken from poorly differentiated squamous cell carcinomas of the nasopharynx. The tissues were prepared for cell culture and eventually two continuous epithelia cell lines were obtained and designated HONE-1 and HNE-1. Light and electron microscopic examination of these two cell lines demonstrated cells with an epithelial morphology including the presence of desmosomes. It was found that early-passage uncloned HNE-1 cells (passage 23) could be superinfected with B95-8 and NPC-EBV isolates as demonstrated by the induction of Epstein-Barr virus (EBV)-specific early antigen(s) in a small percentage of the cells; HONE-1 cells could also be superinfected with EBV. Southern blot analysis detected EBV DNA in samples from uncloned HNE-1 cells at passages 12, 17, 21, 27, and 35. However, by passage 45, EBV DNA could no longer be detected in HNE-1 cells by Southern blot analysis. The EBV genome was detected in parental HONE-1 cells at subculture 9 and in clone 40 cells up to passage 40 thus far. The data suggest that EBV genome-positive HNE-1 and HONE-1 cells were lost as the cells were cultivated in vitro and that cloning the cells at an early passage level may be critical in maintaining EBV genome-positive epithelial NPC cells. These EBV genome-positive epithelia NPC cell lines will be useful for studying the association of EBV and NPC