Abstract:

Objective

To investigate the efficacy of herpes simplex virus(HSV)vector,G47Δfor the treatment of the human breast cancer through the observation of its cytotoxicity on three human breast cancer cell lines,SK-BR-3,MDA-MB-453 and MDA-MB-231.

Methods

Human breast cancer SK-BR-3,MDAMB-453 and MDA-MB-231 cells were cultured and inoculated with G47Δof different multiplicities of infection(MOI).The cytotoxicity was observed every day.G47Δ contained the LacZ gene,whose expression in infected cells was detected with X-gal histochemistry.

Results

G47Δwas highly cytotoxic for SK-BR-3 and MDA-MB-453 cells in vitro at very low MOI(0.01),but no efficiency was observed in MDA-MB-231 cells.X-gal staining of infected tumor cells in vitro illustrated the replication and spread of the virus.In the MOI=0.01 group,on the fifth day after infection,more than 90%SK-BR-3 and MDA-MB-453 cells were killed,but after MDA-MB-231 was infected,in the MOI=0.01 and MOI=0.10 groups,the cell number was similar to the mock.

Conclusions

Recently constructed oncolytic HSV vector G47Δwas effective at killing human breast cancer SK-BR-3 and MDA-MB-453 cells in vitro,but did not influence the growth of MDA-MB-231.The efficiency and deficiency of this novel cancer therapy warrants further investigation and consideration of clinical application.

Key words: Cancer therapy, Herpes simplex virus, Oncolytic virus, Gene therapy, Breast neoplasms