Incorporation of Peptides Targeting EGFR and FGFR1 into the Adenoviral Fiber Knob Domain and Their Evaluation as Targeted Cancer Therapies.
Oncolytic virotherapies based on adenovirus 5 (Ad5) hold promise as adjunctive cancer therapies; however, their efficacy when delivered systemically is hampered by poor target cell specificity and preexisting anti-Ad5 immunity. Ovarian cancer represents a promising target for virotherapy, since the virus can be delivered locally into the peritoneal cavity. Both epidermal growth factor receptor (EGFR) and fibroblast growth factor receptor 1 (FGFR1) are overexpressed in the majority of human tumors, including ovarian cancer. To generate adenoviral vectors with improved tumor specificity, we generated a panel of Ad5 vectors with altered tropism for EGFR and FGFR, rather than the natural Ad5 receptor, hCAR. We have included mutations within AB loop of the viral fiber knob (KO1 mutation) to preclude interaction with hCAR, combined with insertions in the HI loop to incorporate peptides that bind either EGFR (peptide YHWYGYTPQNVI, GE11) or FGFR1 (peptides MQLPLAT, M*, and LSPPRYP, LS). Viruses were produced to high titers, and the integrity of the fiber protein was validated by Western blotting. The KO1 mutation efficiently ablated hCAR interactions, and significantly increased transduction was observed in hCAR(low)/EGFR(high) cell lines using Ad5.GE11, while transduction levels using Ad5.M* or Ad5.LS were not increased. In the presence of physiological concentrations of human blood clotting factor X (hFX), significantly increased levels of transduction via the hFX-mediated pathway were observed in cell lines, but not in primary tumor cells derived from epithelial ovarian cancer (EOC) ascites samples. Ad5-mediated transduction of EOC cells was completely abolished by the presence of 2.5% serum from patients, while, surprisingly, incorporation of the GE11 peptide resulted in significant evasion of neutralization in the same samples. We thus speculate that incorporation of the YHWYGYTPQNVI dodecapeptide within the fiber knob domain may provide a novel means of circumventing preexisting Ad5 immunity that warrants further investigation.
1Institutes of Cancer and Genetics, Cardiff University, Cardiff CF14 4XN, United Kingdom.
Hanni
H
Uusi-Kerttula
1Institutes of Cancer and Genetics, Cardiff University, Cardiff CF14 4XN, United Kingdom.|2Institutes of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom.
Mateusz
M
Legut
1Institutes of Cancer and Genetics, Cardiff University, Cardiff CF14 4XN, United Kingdom.
James
J
Davies
3Velindre Cancer Centre, Cardiff CF14 2TL, United Kingdom.
Rachel
R
Jones
3Velindre Cancer Centre, Cardiff CF14 2TL, United Kingdom.
Emma
E
Hudson
3Velindre Cancer Centre, Cardiff CF14 2TL, United Kingdom.
Louise
L
Hanna
2Institutes of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom.
Richard J
RJ
Stanton
1Institutes of Cancer and Genetics, Cardiff University, Cardiff CF14 4XN, United Kingdom.|3Velindre Cancer Centre, Cardiff CF14 2TL, United Kingdom.
John D
JD
Chester
1Institutes of Cancer and Genetics, Cardiff University, Cardiff CF14 4XN, United Kingdom.
Alan L
AL
Parker
D000256:Adenoviridae / Q000235:genetics* / Q000276:immunology; D000818:Animals; D057134:Antibodies, Neutralizing / Q000276:immunology; D036022:Capsid Proteins / Q000737:chemistry / Q000235:genetics*; D002460:Cell Line; D066246:ErbB Receptors / Q000737:chemistry / Q000235:genetics*; D005260:Female; D015870:Gene Expression; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000235:genetics* / Q000276:immunology; D006801:Humans; D009369:Neoplasms / Q000235:genetics / Q000628:therapy; D009500:Neutralization Tests; D010051:Ovarian Neoplasms / Q000235:genetics / Q000276:immunology / Q000628:therapy; D010455:Peptides / Q000737:chemistry / Q000235:genetics*; D051496:Receptor, Fibroblast Growth Factor, Type 1 / Q000737:chemistry / Q000235:genetics*; D011991:Receptors, Virus / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins; D014161:Transduction, Genetic; D019076:Transgenes
D057134:Antibodies, Neutralizing; D036022:Capsid Proteins; D010455:Peptides; D011991:Receptors, Virus; D011993:Recombinant Fusion Proteins; C085301:adenovirus receptor; C018315:hexon capsid protein, Adenovirus; D066246:ErbB Receptors; D051496:Receptor, Fibroblast Growth Factor, Type 1