In vivo marking of spontaneous or vaccine-induced fibrosarcomas in the domestic house cat, using an adenoviral vector containing a bifunctional fusion protein, GAL-TEK.
We evaluated the ability of a replication-deficient, recombinant adenoviral vector to transfer the bifunctional gene GAL-TEK, which expresses a marking/therapeutic gene product, to naturally occurring cat fibrosarcomas in situ. GAL-TEK contains an in-frame fusion of the bacterial LacZ gene for histochemical marking of tumors with beta-galactosidase (beta-Gal) and the HSV tk gene for enzyme-prodrug activation of the prodrug ganciclovir (GCV) to induce selective tumor cell killing. GAL-TEK bifunctional marking and cell killing activities were tested in vitro after adenoviral vector infection of HT1080 human fibrosarcoma cells. The tk activity of GAL-TEK is shown to be almost as potent as HSV tk to catalyze conversion of GCV to GCV nucleotides and promote selective cell killing. Using 8 cats with recurring 2.5-cm2 fibrosarcomas that either arose spontaneously or were induced by vaccine, we determined experimentally the administration routes and times required for optimum GAL-TEK gene transfer by beta-Gal histological staining and reverse transcriptase polymerase chain reaction to the multiple compartments of the growing fibrosarcomas consonant with minimizing collateral infection of neighboring tissues and other unwanted side effects.
Marini
F C
FC
Department of Experimental Pathology, University of Texas M.D. Anderson Cancer Center, Houston 77054, USA.
Cannon
J P
JP
Belmont
J W
JW
Shillitoe
E J
EJ
Lapeyre
J N
JN
D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D002415:Cats; D002460:Cell Line; D004351:Drug Resistance; D005354:Fibrosarcoma / Q000473:pathology / Q000628:therapy* / Q000821:virology; D015774:Ganciclovir / Q000494:pharmacology; D018014:Gene Transfer Techniques; D005819:Genetic Markers; D005822:Genetic Vectors / Q000737:chemistry* / Q000235:genetics / Q000494:pharmacology; D006801:Humans; D016133:Polymerase Chain Reaction; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics*; D018139:Simplexvirus / Q000201:enzymology / Q000235:genetics; D013937:Thymidine Kinase / Q000096:biosynthesis / Q000235:genetics; D014612:Vaccines; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000235:genetics*
D005819:Genetic Markers; D011993:Recombinant Fusion Proteins; D014612:Vaccines; D013937:Thymidine Kinase; D001616:beta-Galactosidase; D015774:Ganciclovir