inhibits growth and increases radiosensitivity of tumors in nude mice implanted with nasopharygeal carcinoma cells / 中国肿瘤生物治疗杂志

ABSTRACT

Objective:To study the inhibitory effect of E1A gene on the growth of tumors in nude mice implanted with nasopharygeal carcinoma CNE2 cells and its promotion effect on the radiosensitivity of CNE2-implanted tumors,and to investigate the related mechanism.Methods: E1A gene was transfected into CNE2 cells using adenovirus system,and stable E1A positive clones were established.The inhibitory effect of E1A on tumor formation-ability of CNE2 cells was observed in nude mice.The efficacy of E1A gene therapy with or without radiotherapy against CNE2 cell-implanted tumors was evaluated.The effect of E1A gene therapy on the expression of P53 was detected by RT-PCR.Results: CNE2 cells stably transfected with E1A gene(CNE2-Ad-E1A)were successfully established.The tumor formation time was later and tumor size was smaller in CNE2-Ad-E1A cell-implanted mice compared with those in CNE2 cell-and CNE2-Ad-?-gal cell-implanted mice(CNE2 cells stably transfected with Ad-?-gal).Radiotherapy,E1A gene therapy and E1A gene+radiotherapy all suppressed the growth of implanted tumors,with the tumor suppression rates being(60.32?5.34)%,(70.53?6.12)%,and(97.15?4.87)%,respectively.E1A gene therapy significantly increased the expression of P53 gene in tumor tissues.Conclusion: E1A can inhibit the growth of tumors in mice implanted with nasopharygeal carcinoma cells,and enhance its sensitivity to radiotherapy,which may be related to the increased expression of P53 gene in tumor tissues.