摘要
Background and aims:The spectral properties of enhanced greenfluorescent protein(EGFP)used in current visualizable animal models for nasopharyngeal carcinoma(NPC)result in a limited imaging depth.Far-redfluorescent proteins have optimal spectral wavelengths that allow deep tissue penetration,thus are well-suited for the imaging of tumor growth and metastases in live animals.This study aims to establish an imageable animal model of NPC using far-redfluorescent proteins.Methods:Eukaryotic expression vectors of far-redfluorescent proteins,mLumin and Katushka S158A,were separately transfected into 5-8F NPC cells,and cell lines stably expressing the far-redfluorescent proteins were obtained.These cells were intraperitoneally or intravenously injected into mice,and their tumorigenic and metastatic potential were examined throughfluorescence imaging.Finally,factors affecting their tumorigenic ability were further assessed through testing side population(SP)cells proportion byflow cytometry.Results:NPC cell line with high tumorigenicity and metastasis(5-8F-mL2)was screened out,which stably expressed far-redfluorescent protein.Intraperitoneal and intravenous injection of 5-8F-mL2 cells resulted in an abdomen metastasis model and a lung metastasis model.In addition,NPC cell line without tumorigenicity(5-8F-Katushka S158A)was screened out.The percentage of SP cells between 5-8F-mL2 and 5-8F-Katushka S158A was found different,suggesting that the SP cell proportion may play a key role in the determination of cell tumorigenic ability.Conclusion:We successfully established animal models for NPC with high tumorigenicity and metastasis using a super-bright far-redfluorescent protein.Owing to the super-brightness and excellent wavelength parameters,these models may be applied as useful tools for intuitive and efficient monitoring of tumor growth and metastasis,as well as assessing the efficacy of nasopharyngeal cancer drugs.
基金
The authors thank Prof.Yi-Xin Zeng and Prof.Mu-Sheng Zeng(Sun Yat-sen University Cancer Center,Guangzhou,China)for providing the 5-8F cell line.This work was supported by National Natural Science Foundation of China(Grant No.81172153)
National Science and Technology Support Program of China(Grant No.2012BAI23B02).