Human cancers frequently arise from increased expression of proto-oncogenes, such as MYC and HER2. Understanding the cellular pathways regulating the transcription and expression of proto-oncogenes is important for targeted therapies for cancer treatment. Adenoviral (Ad) E1A 243R (243 aa residues) is a viral oncoprotein that interacts with key regulators of gene transcription and cell prolifera...

Adenovirus E1a protein presents an interesting paradox. When expressed in primary rodent cells, E1a facilitates oncogenic transformation by activated ras or an activator of c-src signaling, polyoma middle T protein (1). However, adenovirus E1a is nononcogenic in human cells: adenovirus sequences have not been found in human tumors, despite widespread infection of the human population, and inten...

The largest isoform of adenovirus early region 1A (E1A) contains a unique region termed conserved region 3 (CR3). This region activates viral gene expression by recruiting cellular transcription machinery to the early viral promoters. Recent studies have suggested that there is an optimal level of E1A-dependent transactivation required by human adenovirus (hAd) during infection and that this ma...

The presence of the adenoviral early region 1A (E1A) protein in human lungs has been associated with an increased risk of chronic obstructive pulmonary disease (COPD), possibly by a mechanism involving amplification of proinflammatory responses. We hypothesize that enhanced inflammation results from increased transcription factor activation in E1A-carrying cells, which may afford susceptibility...

Gene therapy with adenoviral early region gene (E1A) may enhance the susceptibility of neoplastic cells to chemotherapy-induced cell death. Our previous study developed a urothelium-specific oncolytic serotype 5 adenovirus (Ad5) with the uroplakin II (UPII) promoter controlling E1A expression. The present study investigated whether this urothelium-specific recombinant adenovirus (Ad5-UPII-E1A) ...

The human adenovirus type 5 (HAdV-5) E1A 13S oncoprotein is a potent regulator of gene expression and is used extensively as a model for transcriptional activation. It possesses two independent transcriptional activation domains located in the N-terminus/conserved region (CR) 1 and CR3. The protein acetyltransferase p300 was previously identified by its association with the N-terminus/CR1 porti...

The adenoviral protein E1A associates with multiple anticancer activities, including stabilization of p53 tumor suppressor, and has been tested through gene therapy approaches in clinical trials. To identify potential E1A-binding proteins involved in E1A's anticancer activities, we screened a yeast two-hybrid library and identified Mdm4, an Mdm2-related p53-binding protein, as a novel E1A-bindi...

The adenoviral oncoprotein E1A influences cellular regulation by interacting with a number of cellular proteins. In collaboration with complementary oncogenes, E1A fully transforms primary cells. As part of this action, E1A inhibits transcription of c-Jun:Fos target genes while promoting that of c-Jun:ATF2-dependent genes including jun. Both c-Jun and ATF2 are hyperphosphorylated in response to...

BACKGROUND We have previously developed an oncolytic serotype 5 adenovirus (Ad5) with chromogranin-A (CgA) promoter-controlled E1A expression, Ad[CgA-E1A], with the intention to treat neuroendocrine tumors, including carcinoids. Since carcinoids tend to metastasize to the liver it is important to fully repress viral replication in hepatocytes to avoid adenovirus-related liver toxicity. Herein, ...