ABSTRACT
Objective To study the growth difference and possible mechanism between nasopharyngeal carcinoma (NPC) cell line CNE-2 and its subclone S-18.Methods CNE-2 and S-18 cells were cultured in vitro.6 x 105 cells/mouse were xenografted subcutaneously in the back of nude mice.The volumes of rumors were measured on the 3 rd,7 th,10 th,14 th day after grafting.Mice were sacrificed on the 14 th day and tumors were isolated and weighed.RNA from tumor tissues were extracted and transcriptional levels of HSP27 and NF-K B were detected.Results (1) S-18,instead of CNE-2,grew to form tumor mass 7 days after xenografting subcutaneously;both cell lines formed tumor mass 10 days after xenografting,however,the volumes of S-18 tumors [(223.13 ± 21.32) mm3,10 th day;(420.25 ± 24.52) mm3,14 th day] were significant bigger than CNE-2tumors [(113.70±11.70) mm3,10thday;(279.86±25.78) mm3,14thday];The weights of S-18 umors were significantly higher than CNE-2 tumors on the 14 th day after xenografting;(2) The transcriptional levels of HSP27 and NF-KB in S-18 tumor were significantly higher than in CNE-2 tumor.Conclusion Xenografted S-18 NPC grows faster than Xenografted CNE-2 NPC.HSP27 and NF-κ B are probably involved in the regulation of growth in NPC.