title: Conditionally replication-competent adenoviral vectors with enhanced infectivity for use in gene therapy of melanoma.
abstract: To generate vector Ad.Tyr-E1A, which is cytolytic for tyrosinase-positive melanoma cells, we replaced the adenoviral E1A promoter with a human tyrosinase enhancer/promoter. To overcome the low transduction efficiency in populations of melanoma cells that exhibit a low level of the coxsackievirus-adenovirus receptor (CAR), we inserted an RGD-4C peptide into the HI loop of the fiber knob domain of the Ad.Tyr-E1A vector. The resulting vector was named Ad.Tyr-E1A(RGD). As a result of these changes, the transduction efficiency of the RGD-modified vector was increased both in vitro and in vivo. Western blot analysis proved that infection of cells with the Ad.Tyr-E1A(RGD) vector led to expression of the E1A gene selectively in tyrosinase-positive melanoma cell lines, but not in tyrosinase-negative cell lines. The Ad.Tyr-E1A(RGD) vector was as potent in its cytotoxic effect as a tumor nonselective vector (Ad.CMV-E1A) in tyrosinase-positive melanoma cell lines. The Ad.Tyr-E1A(RGD) vector produced a higher vector particle yield in tumor cells than did the Ad.Tyr-E1A vector. Intratumoral injection of the Ad.Tyr-E1A(RGD) vector into xenotransplanted human melanoma tumors led to tumor regression in vivo. The combination of tumor-specific replication and enhanced infectivity generates a more potent CRAD vector for gene therapy of melanoma.
authors.affiliation: Sidney Kimmel Cancer Center, San Diego, CA 92121, USA.
authors.forename: Yanzheng
authors.initials: Y
authors.lastname: Liu
authors.forename: Tao
authors.initials: T
authors.lastname: Ye
authors.forename: Dejun
authors.initials: D
authors.lastname: Sun
authors.forename: Jonathan
authors.initials: J
authors.lastname: Maynard
authors.forename: Albert
authors.initials: A
authors.lastname: Deisseroth
mesh_terms: D000256:Adenoviridae / Q000235:genetics*; D017500:Adenovirus E1A Proteins / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D036022:Capsid Proteins / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D004742:Enhancer Elements, Genetic / Q000235:genetics; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics* / Q000627:therapeutic use; D006801:Humans; D008545:Melanoma / Q000378:metabolism / Q000628:therapy*; D051379:Mice; D016513:Mice, SCID; D014442:Monophenol Monooxygenase / Q000235:genetics / Q000378:metabolism; D009842:Oligopeptides / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D011991:Receptors, Virus / Q000378:metabolism; D014779:Virus Replication / Q000235:genetics; D023041:Xenograft Model Antitumor Assays
chemical_list: D017500:Adenovirus E1A Proteins; D036022:Capsid Proteins; D009842:Oligopeptides; D011991:Receptors, Virus; C085301:adenovirus receptor; C018315:hexon capsid protein, Adenovirus; C047981:arginyl-glycyl-aspartic acid; D014442:Monophenol Monooxygenase