An In Vitro Study On Anti-Hepatocellular Carcinoma Effect Of Minicircle DNA Expressing Anti-IGF1R/CD3

Determination of effective targets is a prerequisite in cancer immune therapy.Insulin-like growth factor(IGF1R),a tumor marker over-expressed on the HCC cells surface,has become as a promising target for anticancer immunotherapies.During the past decade,several monoclonal antibodies(m Abs)against IGFR have been developed and some of which are undergoing clinical trails.However,the anticancer effect of m Abs,which kill cancer cells via antibody-dependent cell-mediated cytotoxicity(ADCC),is very limited.Recently,bispecific antibod ies(Bs Abs),which redirect T cells to kill cancer cells,emerge as a promising anticancer immunotherapy.Numerous preclinical and clinical studies de monstrated that Bs Abs are up to 10-thousand folds more effective than their m Ab counterparts.Nevertheless,because of their short half-life,Bs Abs need repeated injection to be effective.We proposed to overcome this problem by using minicircle,an enhanced nonviral DNA evctor,to stably express Bs Ab in vivo.In this thesis,the following experiments have been finished: 1)construction of a MC.IGF1R/CD3 minicircle vector to produce anti-IGF1R/CD3 Bs Ab in cells,and 2)development of a novel gene de livery system(st PEI-Ca P/MC.DNA)to deliver the MC.IGF1R/CD3 vector into cultured cells efficiently.We demonstrated that the st PEI-Ca P/MC.DNA gene delivery system resulted in effective gene transfection with little cytotoxicity in HEK293 t cell transfection,and that the HCC cells are susceptible to the anti-IGF1R/CD3 Bs Ab redirected T-cells lysis in vitro.In summary,this proof-of-concept study demonstrates the feasibility of MC.IGF1R/CD3 as a potential anti-HCC gene drug worthy of futher investigation.