Establishment Of Patient Derived Xenograft Models Of Lung Cancer And Application In The Preclinical Study Of Nanoparticles

BackgroundLung cancer is the leading cause of cancer-related death all over the world.Various of therapies have developed in recent decades,the overall 5-year survival rate is still poor.Majority of patients need to accept several antitumor drugs.Unfortunately,due to the fact that models used for drug development cannot faithfully recapitulate the initial characteristics of the tumor,a large number of clinical trials of antitumor drug have failed.In recent years,patient derived tumor xenograft(PDX)models have been considered a promising solution.Objective1.To explore the establishment procedure,characteristics and impact-factors for engraftment of patient derived xenograft model of human lung cancer.2.To evaluate the efficacy,safety and mechanism of a novel nanoparticle for treatment of non-small cell lung cancer(NSCLC)by using PDX models.Methods.1.Three approaches of engraftment were used to establish PDX models of human lung cancer,and the impact factors related to take rates were analysed.2.HE staining,immunohistochemistry(IHC)and whole exome sequencing were used for identification of the consistency between the models and the original tumor.3.The inhibition effect and the in vivo safety of Gd-metallofullerenol for two subtype of non small cell lung cancer were observed by using PDX models.4.The diverse antitumor mechanism of Gd-metallofullerenol between the two models was compared by real-time PCR,western-blot,and immunohistochemistry.Results1.Thirty-two cases of lung cancer samples were collected.Three strains of immunodeficiency mice were adopted to establishe four subtype of lung cancer PDX models by three approaches.The overall successful rate was 46.9%.2.The growth rate of PDX models accelerated with generations and the characteristics of the original tumor maintained within the first three generations,in the aspect of morphology,immunohistochemical markers and molecular levels.3.The engraftment rate in cases with microinvasive(70.6%)was significantly higher than those with non-microinvasive(20%).Significant different modeling rate was seen by different strains of mice.The gender of patient,the history of smoking,the approaches of modeling,the classification,differentiation and TNM stages of primary tumor made no significant impact on model engraft rate in our series.4.In PDX105,the average tumor volume was obviously lower in Gd-metallofullerenol group than that of PBS group with significant difference(p<0.01).The inhibitory rate of Gd-metallofullerenol(80.34%)was significantly higher than that of cisplatin(33.86%)and fullerol(35.22%).In PDX122,the average volume of tumor in three treatment group was significantly lower than that of PBS group(p<0.05).The inhibitory rate of Gd-metallofullerenol(53.26%)was slightly higher than that of cisplatin(48.37%)and fullerol(30.96%).5.Quantitative real-time PCR suggested that four genes related to tumor invasion and metastasis expressed differently within the two PDX models.In PDX105,the alpha-catenin was up-regulated and MMP9 was down-regulated in the cisplatin group.While up-regulated of alpha-catenin,e-cadherin,and MMP2,but down-regulated of MMP9 was seen in Gd-metallofullerenol and fullerol group.In PDX122,all the four genes expression up-regulated in cisplatin group,while down-regulated of the four genes was detected in the Gd-metallofullerenol and fullerol group.Western-blotting test indicated that MMP9 and MMP2 were down-regulated in PDX105,while in PDX 122 only MMP9 was down-regulated by Gd-metallofullerenol.7.Body weight analysis showed that,in PDX105,compared to the normal group,significant weight loss was seen in cisplatin and fullerol group(p<0.05),while no significant difference was seen in PBS group and Gd-metallofullerenol group(p>0.05).In PDX122,the weight loss of PBS group,cisplatin group,fullerol group and Gd-metallofullerenol group was all serious,but Gd-metallofullerenol group was the closest to the normal group.8.The biochemistry test of blood and HE examination of mice organs indicated that the Gd-metallofullerenol had no obvious side effect on mice,but slight kidney toxicity for mice from cisplatin was observed.Conclusions1.PDX models can maintain original characteristics of the different subtypes of lung cancer,provide a good platform for preclinical cancer research and individualized therapy.2.Microinvasion of the primary tumor and the immunodeficiency degree of the mice has significant effects on establishment rate of the PDX models.3.Gd-metallofullerenol nanoparticles inhibit the growth of non-small cell lung cancer,especially squamous cell lung cancer,with favourable biosafety.New opportunities may be expected for the treatment of squamous cell lung carcinoma.