Skip to main content
An official website of the United States government
Government Funding Lapse
Because of a lapse in government funding, the information on this website may not be up to date, transactions submitted via the website may not be processed, and the agency may not be able to respond to inquiries until appropriations are enacted.

The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit cc.nih.gov.

Updates regarding government operating status and resumption of normal operations can be found at opm.gov.

Ad5.SSTR/TK.RGD

An RGD-4C-modified, infectivity-enhanced, bicistronic type 5 adenovirus expressing herpes simplex virus thymidine kinase (HSV-tk) gene, a therapeutic suicide gene, and the somatostatin receptor type 2 (SSTR2) gene with potential antineoplastic activity. Modification with the double cyclic peptide RGD-4C allows the virus to bind to cellular integrins, frequently expressed on the surfaces of ovarian cancer cells, instead of the coxsackie and adenovirus (CAR) receptor, which is often nonfunctional in ovarian cancer cells. Upon intratumoral administration, Ad5.SSTR/TK.RGD transfects tumor cells and expresses the HSV-tk gene. After subsequent administration of a synthetic acyclic guanosine analogue prodrug like ganciclovir (GCV), expressed HSV-tk phosphorylates and activates the prodrug, which may result in inhibition of DNA synthesis and apoptosis in HSV-tk-expressing cancer cells. Additionally, as a bystander effect, adjacent non-transfected cells may be killed by the activated antiviral drug. SSTR2 expression allows imaging of gene transfer into tumor cells using a radiolabeled somatostatin analogue.
Synonym:RGD-modified adenoviral vector encoding SSTR/TK
Search NCI's Drug Dictionary