title: Adenovirus-mediated expression of p53 or p21 in a papillary serous endometrial carcinoma cell line (SPEC-2) results in both growth inhibition and apoptotic cell death: potential application of gene therapy to endometrial cancer.
abstract: Papillary serous endometrial carcinoma is an aggressive tumor characterized by late-stage presentation, i.p. spread, and poor prognosis. It is histologically similar to serous papillary carcinoma of the ovary. Preclinical studies have shown that adenovirus-mediated expression of p53 in ovarian cancer cell lines causes growth inhibition and apoptosis in vitro and in vivo. Such studies provide the rationale for Phase I Adp53 gene therapy clinical trials in ovarian cancer. In the present study, we compared the efficacy of adenoviral vectors containing p53 (Adp53) or p21 (Adp21) in a papillary serous endometrial tumor cell line (SPEC-2) that contains mutated p53. Growth assays revealed that both Adp53 and Adp21 were efficacious in decreasing cell proliferation as assessed by anchorage-dependent and anchorage-independent growth assays. However, as compared with Adp53, the effects of Adp21 tended to be more transient and less marked. Strikingly, Adp21, but not Adp53, induced a G1 arrest in SPEC-2 endometrial adenocarcinoma cells. In contrast, as assessed by induction of hypodiploid peaks, free DNA ends detected by a terminal deoxynucleotidyl transferase-based assay, and annexin V positivity, p53 was more effective than p21 in inducing cell death by apoptosis. Compatible with the more efficient induction of apoptosis, Adp53, but not Adp21, induced a marked increase in expression of the preapoptotic molecule BAX without a concomitant change in expression of the antiapoptotic mediator Bcl-2. The differential effects of Adp53 and Adp21 on cell cycle progression and apoptosis may be related to the reversibility of p21-induced cell cycle arrest and the irreversibility of p53-induced apoptosis. Thus, at least in the papillary serous endometrial carcinoma cell line SPEC-2, Adp53 may be more effective than Adp21 as a gene therapeutic. Nevertheless, these preclinical studies suggest that papillary serous endometrial carcinoma is a potential target for p53- or p21-mediated gene therapy.
authors.affiliation: Department of Gynecologic Oncology, The University of Texas, M.D. Anderson Cancer Center, Houston 77030, USA.
authors.forename: L
authors.initials: L
authors.lastname: Ramondetta
authors.forename: G B
authors.initials: GB
authors.lastname: Mills
authors.forename: T W
authors.initials: TW
authors.lastname: Burke
authors.forename: J K
authors.initials: JK
authors.lastname: Wolf
mesh_terms: D000256:Adenoviridae; D017304:Annexin A5 / Q000032:analysis; D017209:Apoptosis; D002448:Cell Adhesion; D002453:Cell Cycle; D002455:Cell Division; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins / Q000235:genetics / Q000378:metabolism*; D018283:Cystadenocarcinoma, Papillary / Q000628:therapy; D016889:Endometrial Neoplasms / Q000628:therapy; D004791:Enzyme Inhibitors / Q000378:metabolism; D005260:Female; D016158:Genes, p53; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006801:Humans; D020287:In Situ Nick-End Labeling; D011518:Proto-Oncogene Proteins / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2; D014162:Transfection / Q000379:methods; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*; D051028:bcl-2-Associated X Protein
chemical_list: D017304:Annexin A5; C494826:BAX protein, human; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004791:Enzyme Inhibitors; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein