title: Preclinical Justification of pbi-shRNA EWS/FLI1 Lipoplex (LPX) Treatment for Ewing's Sarcoma.
abstract: The EWS/FLI1 fusion gene is well characterized as a driver of Ewing's sarcoma. Bi-shRNA EWS/FLI1 is a functional plasmid DNA construct that transcribes both siRNA and miRNA-like effectors each of which targets the identical type 1 translocation junction region of the EWS/FLI1 transcribed mRNA sequence. Previous preclinical and clinical studies confirm the safety of this RNA interference platform technology and consistently demonstrate designated mRNA and protein target knockdown at greater than 90% efficiency. We initiated development of pbi-shRNA EWS/FLI1 lipoplex (LPX) for the treatment of type 1 Ewing's sarcoma. Clinical-grade plasmid was manufactured and both sequence and activity verified. Target protein and RNA knockdown of 85-92% was demonstrated in vitro in type 1 human Ewing's sarcoma tumor cell lines with the optimal bi-shRNA EWS/FLI1 plasmid. This functional plasmid was placed in a clinically tested, liposomal (LP) delivery vehicle followed by in vivo verification of activity. Type 1 Ewing's sarcoma xenograft modeling confirmed dose related safety and tumor response to pbi-shRNA EWS/FLI1 LPX. Toxicology studies in mini-pigs with doses comparable to the demonstrated in vivo efficacy dose resulted in transient fever, occasional limited hypertension at low- and high-dose assessment and transient liver enzyme elevation at high dose. These results provide the justification to initiate clinical testing.
authors.affiliation: Strike Bio, Carrollton, Texas, USA.
authors.forename: Donald D
authors.initials: DD
authors.lastname: Rao
authors.affiliation: Strike Bio, Carrollton, Texas, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Jay
authors.affiliation: Strike Bio, Carrollton, Texas, USA.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Strike Bio, Carrollton, Texas, USA.
authors.forename: Xiuquan
authors.initials: X
authors.lastname: Luo
authors.affiliation: Gradalis, Inc., Dallas, Texas, USA.
authors.forename: Padmasini
authors.initials: P
authors.lastname: Kumar
authors.affiliation: Strike Bio, Carrollton, Texas, USA.
authors.forename: Hilary
authors.initials: H
authors.lastname: Eysenbach
authors.affiliation: Mary Crowley Cancer Research Centers, Dallas, Texas, USA.|Texas Oncology, P.A., Dallas, Texas, USA.|Medical City Dallas Hospital, Dallas, Texas, USA.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Ghisoli
authors.affiliation: Gradalis, Inc., Dallas, Texas, USA.|Mary Crowley Cancer Research Centers, Dallas, Texas, USA.
authors.forename: Neil
authors.initials: N
authors.lastname: Senzer
authors.affiliation: Gradalis, Inc., Dallas, Texas, USA.|Mary Crowley Cancer Research Centers, Dallas, Texas, USA.|Texas Oncology, P.A., Dallas, Texas, USA.|Medical City Dallas Hospital, Dallas, Texas, USA.
authors.forename: John
authors.initials: J
authors.lastname: Nemunaitis
mesh_terms: D000818:Animals; D001665:Binding Sites; D045744:Cell Line, Tumor; D016207:Cytokines / Q000378:metabolism; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D005260:Female; D055785:Gene Knockdown Techniques; D023061:Gene Order; D015316:Genetic Therapy; D006801:Humans; D018836:Inflammation Mediators; D008081:Liposomes; D008297:Male; D015514:Oncogene Proteins, Fusion / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics*; D010957:Plasmids / Q000008:administration & dosage / Q000235:genetics; D051789:Proto-Oncogene Protein c-fli-1 / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics*; D034802:RNA-Binding Protein EWS / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics*; D012512:Sarcoma, Ewing / Q000235:genetics* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D052416:Targeted Gene Repair; D014162:Transfection; D047368:Tumor Burden; D023041:Xenograft Model Antitumor Assays
chemical_list: D016207:Cytokines; C106031:EWS-FLI fusion protein; D018836:Inflammation Mediators; D008081:Liposomes; D015514:Oncogene Proteins, Fusion; D051789:Proto-Oncogene Protein c-fli-1; D034741:RNA, Small Interfering; D034802:RNA-Binding Protein EWS