The majority of solid cancers are of epithelial origin. A hallmark of epithelial cells are tight and adherens junctions. Tight and adherens junctions seal intercellular spaces and significantly limit the perfusion of anti- tumor agents such as drugs, antibodies, and immune cells within the tumor, thus severely diminishing the efficacy of such therapeutic modalities. The epithelial phenotype of cancer cells also represents a barrier to infection with commonly used adenoviruses (Ads) that target CD46 or the coxsackie-adenovirus receptor (CAR), due to trapping of these receptors in tight and adherens junctions which explains, in part, why these serotypes are inefficient in cancer gene therapy. We found however, that specific human species B adenoviruses, namely Ad3, Ad7, Ad11, and Ad14 (AdB-group 2) that use a yet unknown receptor (receptor X), which is different from CAR and CD46, efficiently infect epithelial cancer cells. This makes these serotypes potential tools for virotherapy of cancer as well as for gene transfer into normal epithelial tissue. In addition, these serotypes are important pathogens, exemplified by recent outbreaks of a highly pathogenic new Ad14 stain (Ad14a) that also uses receptor X. Furthermore, we have shown that recombinant Ad3 dodecahedra (PtDd) formed through interaction of 12 penton bases with protruding fibers can enter epithelial cancer cells and faciliate uptake of Ads (and potentially other tumor agents) for which tight and adherens junctions represent a barrier. Based on the importance of Ad3, 7, 11, and 14 as pathogens and potential vectors for gene therapy, the central goals of this proposal are to identify receptor X, to delineate the mechanism of AdB- group 2 and PtDd uptake in normal and malignant epithelial cells, and to develop AdB-group 2 vectors and PtDd-derivatives as vehicles for gene or drug delivery into epithelial cancers.

Public Health Relevance

In cancers of epithelial origin, tight and adherens junctions seal intercellular spaces and severely diminish the efficacy of anti-tumor agents. The central goals of this proposal are to understand how adenovirus serotypes Ad3, Ad7, Ad11, and Ad14 infect normal and malignant epithelial cells and to develop derivatives of these adenoviruses as vehicles for gene or drug delivery into epithelial cancers.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA144057-10
Application #
8586306
Study Section
Gene and Drug Delivery Systems Study Section (GDD)
Program Officer
Forry, Suzanne L
Project Start
2005-03-01
Project End
2014-11-30
Budget Start
2013-12-01
Budget End
2014-11-30
Support Year
10
Fiscal Year
2014
Total Cost
$296,035
Indirect Cost
$114,887
Name
University of Washington
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195