Gene transfer to ovarian cancer versus normal tissues with fiber-modified adenoviruses.

Adenovirus serotype 5 (Ad5) displays unparalleled gene transfer efficacy to cells with high coxsackie-adenovirus receptor (CAR) expression. Unfortunately, cells isolated from clinical human cancers, both ovarian and other types, express highly variable and often low levels of CAR. Fortunately, native Ad5 tropism can be modified to circumvent CAR deficiency and to enhance infectivity. Ad5/3luc1 incorporates the serotype 3 fiber knob and binds to a receptor distinct from CAR, while the fiber of Ad5lucRGD is modified with an RGD-4C motif, allowing CAR-independent binding to integrins. We studied the liver tropism and blood clearance of these viruses after intravenous (i.v.) injection, and biodistribution after intraperitoneal (i.p.) injection to tumor-bearing mice. To estimate efficacy, we assessed gene transfer to purified human primary ovarian cancer cells, and in a mouse model of ovarian cancer. Ad5/3luc1 achieved improved gene transfer over Ad5lucRGD, and both infectivity-enhanced viruses were superior to the isogenic control with an unmodified Ad5 capsid. In the presence of malignant ascites, gene transfer was improved with both Ad5/3luc1 and Ad5lucRGD. Thus, retargeting to the Ad3 receptor enhances gene transfer to clinically relevant ovarian cancer substrates, while the mouse toxicity and biodistribution profile of both fiber-modified Ad vectors is comparable to Ad5.

Kanerva A ，Wang M ，Bauerschmitz GJ ，Lam JT ，Desmond RA ，Bhoola SM ，Barnes MN ，Alvarez RD ，Siegal GP ，Curiel DT ，Hemminki A ... -  《MOLECULAR THERAPY》

A human adenoviral vector with a chimeric fiber from canine adenovirus type 1 results in novel expanded tropism for cancer gene therapy.

Stoff-Khalili MA ，Rivera AA ，Glasgow JN ，Le LP ，Stoff A ，Everts M ，Tsuruta Y ，Kawakami Y ，Bauerschmitz GJ ，Mathis JM ，Pereboeva L ，Seigal GP ，Dall P ，Curiel DT ... -  《GENE THERAPY》

Targeting adenovirus to the serotype 3 receptor increases gene transfer efficiency to ovarian cancer cells.

Kanerva A ，Mikheeva GV ，Krasnykh V ，Coolidge CJ ，Lam JT ，Mahasreshti PJ ，Barker SD ，Straughn M ，Barnes MN ，Alvarez RD ，Hemminki A ，Curiel DT ... -  《CLINICAL CANCER RESEARCH》

Genetic replacement of the adenovirus shaft fiber reduces liver tropism in ovarian cancer gene therapy.

Breidenbach M ，Rein DT ，Wang M ，Nettelbeck DM ，Hemminki A ，Ulasov I ，Rivera AR ，Everts M ，Alvarez RD ，Douglas JT ，Curiel DT ... -  《HUMAN GENE THERAPY》

Fiber-knob modifications enhance adenoviral tropism and gene transfer in malignant glioma.

Malignant gliomas remain refractory to Ad5-mediated gene therapy due to deficiency of the coxsackie adenovirus receptor on tumor cells. The purpose of this study was to evaluate whether changes in adenoviral tropism can enhance gene transfer in the context of malignant glioma. We have identified several receptors that are over-expressed on tumor cells and created a series of pseudotyped Ad5 vectors that recognize these receptors: Ad5-RGD which binds alpha(v)beta3/alpha(v)beta5 integrins; Ad5/3 which contains adenovirus serotype 3 knob and binds to CD46; Ad5-Sigma which incorporates the reovirus sigma knob and binds to junctional adhesion molecule-1; and Ad5-pk7 which contains the polylysine motif and binds heparan sulfate proteoglycans. We also investigated the Ad5-CAV1 vector, which contains the knob of canine adenovirus type 1, a virus previously shown to infect glioma via an unknown mechanism. In this study, we compared these modified vectors for their ability to promote the expression of luciferase transgene both in vitro and in vivo. Our results indicate that all five modified vectors attained higher mean luciferase activity vs. control. Among them, Ad5-CAV1 and Ad5-pk7 attained the highest transduction efficiency independent of different tumor lines or infection time. Ad5-Sigma and Ad5-pk7 also demonstrated the least nonspecific infection in normal human astrocytes. Most importantly, Ad5-pk7 achieved 1000-fold increased transgene expression in human glioma xenografts in vivo. These results indicate that modifications of adenoviral tropism can enhance gene transfer in tumors that are poorly susceptible to adenoviral vectors and warrant further development of Ad5-pk7 for glioma gene therapy.

Zheng S ，Ulasov IV ，Han Y ，Tyler MA ，Zhu ZB ，Lesniak MS ... -  《JOURNAL OF GENE MEDICINE》