title: Inflammation, apoptosis, and necrosis induced by neoadjuvant fas ligand gene therapy improves survival of dogs with spontaneous bone cancer.
abstract: Fas ligand (FasL) gene therapy for cancer has shown promise in rodents; however, its efficacy in higher mammals remains unknown. Here, we used intratumoral FasL gene therapy delivered in an adenovirus vector (Ad-FasL) as neoadjuvant to standard of care in 56 dogs with osteosarcoma. Tumors from treated dogs had greater inflammation, necrosis, apoptosis, and fibrosis at day 10 (amputation) compared to pretreatment biopsies or to tumors from dogs that did not receive Ad-FasL. Survival improvement was apparent in dogs with inflammation or lymphocyte-infiltration scores >1 (in a 3-point scale), as well as in dogs that had apoptosis scores in the top 50th percentile (determined by cleaved caspase-3). Survival was no different than that expected from standard of care alone in dogs with inflammation scores ≤1 or apoptosis scores in the bottom 50th percentile. Reduced Fas expression by tumor cells was associated with prognostically advantageous inflammation, and this was seen only in dogs that received Ad-FasL. Together, the data suggest that Ad-FasL gene therapy improves survival in a subset of large animals with naturally occurring tumors, and that at least in some tumor types like osteosarcoma, it is most effective when tumor cells fail to express Fas.
authors: ApopLogic Pharmaceuticals, Aurora, CO, USA. modiano@umn.edu
authors: Jaime F
authors: JF
authors: Modiano
authors: Donald
authors: D
authors: Bellgrau
authors: Gary R
authors: GR
authors: Cutter
authors: Susan E
authors: SE
authors: Lana
authors: Nicole P
authors: NP
authors: Ehrhart
authors: Ej
authors: E
authors: Ehrhart
authors: Vicki L
authors: VL
authors: Wilke
authors: J Brad
authors: JB
authors: Charles
authors: Sibyl
authors: S
authors: Munson
authors: Milcah C
authors: MC
authors: Scott
authors: John
authors: J
authors: Pozniak
authors: Cathy S
authors: CS
authors: Carlson
authors: Jerome
authors: J
authors: Schaack
authors: Richard C
authors: RC
authors: Duke
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics / Q000502:physiology; D001859:Bone Neoplasms / Q000235:genetics / Q000378:metabolism / Q000628:therapy*; D004285:Dogs; D053222:Fas Ligand Protein / Q000235:genetics*; D015316:Genetic Therapy / Q000379:methods*; D009336:Necrosis; D012516:Osteosarcoma / Q000235:genetics / Q000378:metabolism / Q000628:therapy
chemical_list: D053222:Fas Ligand Protein