First Author | Martin-Oliva D | Year | 2006 |
Journal | Cancer Res | Volume | 66 |
Issue | 11 | Pages | 5744-56 |
PubMed ID | 16740713 | Mgi Jnum | J:110110 |
Mgi Id | MGI:3639377 | Doi | 10.1158/0008-5472.CAN-05-3050 |
Citation | Martin-Oliva D, et al. (2006) Inhibition of poly(ADP-ribose) polymerase modulates tumor-related gene expression, including hypoxia-inducible factor-1 activation, during skin carcinogenesis. Cancer Res 66(11):5744-56 |
abstractText | Poly(ADP-ribose) polymerase (PARP)-1, an enzyme that catalyzes the attachment of ADP ribose to target proteins, acts as a component of enhancer/promoter regulatory complexes. In the present study, we show that pharmacologic inhibition of PARP-1 with 3,4-dihydro-5-[4-(1-piperidinyl)butoxyl]-1(2H)-isoquinolinone (DPQ) results in a strong delay in tumor formation and in a dramatic reduction in tumor size and multiplicity during 7,12-dimethylbenz(a)anthracene plus 12-O-tetradecanoylphorbol-13-acetate-induced skin carcinogenesis. This observation was parallel with a reduction in the skin inflammatory infiltrate in DPQ-treated mice and tumor vasculogenesis. Inhibition of PARP also affected activator protein-1 (AP-1) activation but not nuclear factor-kappaB (NF-kappaB). Using cDNA expression array analysis, a substantial difference in key tumor-related gene expression was found between chemically induced mice treated or not with PARP inhibitor and also between wild-type and parp-1 knockout mice. Most important differences were found in gene expression for Nfkbiz, S100a9, Hif-1alpha, and other genes involved in carcinogenesis and inflammation. These results were corroborated by real-time PCR. Moreover, the transcriptional activity of hypoxia-inducible factor-1alpha (HIF-1alpha) was compromised by PARP inhibition or in PARP-1-deficient cells, as measured by gene reporter assays and the expression of key target genes for HIF-1alpha. Tumor vasculature was also strongly inhibited in PARP-1-deficient mice and by DPQ. In summary, this study shows that inhibition of PARP on itself is able to control tumor growth, and PARP inhibition or genetic deletion of PARP-1 prevents from tumor promotion through their ability to cooperate with the activation AP-1, NF-kappaB, and HIF-1alpha. |