Treatment of normal and tumor cells with DNA-damaging agents induces not only cell death but also rapid and irreversible proliferation arrest accompanied by phenotypic markers of cell senescence. This accelerated senescence response is positively regulated by p53 and p21 but can also occur in p53- or p21-deficient cells. p21-overexpressing tumor cells and normal senescent fibroblasts show increased expression of proteins with paracrine tumor-promoting activities. HCT1 16 colon carcinoma cells that became senescent after doxorubicin treatment were separated from proliferating cells and analyzed by differential cDNA microarray hybridization. Accelerated senescence was associated with downregulation of multiple genes that act in mitosis, DNA replication, or RNA processing. Senescent cells also showed increased expression of many intracellular and secreted growth inhibitors, as well as secreted mitogenic and angiogenic factors, proteases, extracellular matrix components and receptors, and different transcription factors. In the proposed study, p53-I- and p21-/- derivatives of HCT1 16 cells will be used to determine which of the genes that show altered expression in senescent cells are regulated through p53 or p21. Genes that show similar changes in the senescent cells of different tumor types will be identified as potential markers of accelerated senescence. HCT1 16 lines will be selected for improved recovery from drug-induced growth arrest and analyzed for changes in gene expression. Growth-inhibiting and transcription factor genes that show altered expression in senescent cells will be tested for their effects on cell growth, drug response and expression of other senescence-associated genes. Promoter sequences of genes that are up- or downregulated in accelerated senescence will be analyzed, and transcription factor binding sites shared by co-regulated genes will be identified. The role of candidate regulatory sites will be tested by promoter mutagenesis and transient transfection assays. Stably transfected cell lines with a reporter gene transcribed from the promoters of different senescence-associated genes will be developed as the basis for high-throughput screening of compounds that affect gene expression in accelerated senescence. The ability to modulate growth arrest and paracrine effects in accelerated senescence of tumor cells may help to improve the efficacy and decrease the side effects of cancer treatment.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA089636-06
Application #
6895131
Study Section
Experimental Therapeutics Subcommittee 1 (ET)
Program Officer
Forry, Suzanne L
Project Start
2001-06-01
Project End
2008-05-31
Budget Start
2005-06-01
Budget End
2008-05-31
Support Year
6
Fiscal Year
2005
Total Cost
$273,900
Indirect Cost
Name
Ordway Research Institute, Inc.
Department
Type
DUNS #
124361945
City
Albany
State
NY
Country
United States
Zip Code
12208
Maliyekkel, Anil; Davis, Brian M; Roninson, Igor B (2006) Cell cycle arrest drastically extends the duration of gene silencing after transient expression of short hairpin RNA. Cell Cycle 5:2390-5
Vigneron, Arnaud; Roninson, Igor B; Gamelin, Erick et al. (2005) Src inhibits adriamycin-induced senescence and G2 checkpoint arrest by blocking the induction of p21waf1. Cancer Res 65:8927-35
Nickoloff, Brian J; Lingen, Mark W; Chang, Bey-Dih et al. (2004) Tumor suppressor maspin is up-regulated during keratinocyte senescence, exerting a paracrine antiangiogenic activity. Cancer Res 64:2956-61
Poole, Jason C; Thain, Alison; Perkins, Neil D et al. (2004) Induction of transcription by p21Waf1/Cip1/Sdi1: role of NFkappaB and effect of non-steroidal anti-inflammatory drugs. Cell Cycle 3:931-40
Shay, Jerry W; Roninson, Igor B (2004) Hallmarks of senescence in carcinogenesis and cancer therapy. Oncogene 23:2919-33
Roninson, Igor B (2003) Tumor cell senescence in cancer treatment. Cancer Res 63:2705-15
Roninson, Igor B; Dokmanovic, Milos (2003) Induction of senescence-associated growth inhibitors in the tumor-suppressive function of retinoids. J Cell Biochem 88:83-94
Zhu, Hongming; Chang, Bey-Dih; Uchiumi, Takeshi et al. (2002) Identification of promoter elements responsible for transcriptional inhibition of polo-like kinase 1 and topoisomerase IIalpha genes by p21(WAF1/CIP1/SDI1). Cell Cycle 1:59-66
Gregory, David J; Garcia-Wilson, Elisa; Poole, Jason C et al. (2002) Induction of transcription through the p300 CRD1 motif by p21WAF1/CIP1 is core promoter specific and cyclin dependent kinase independent. Cell Cycle 1:343-50
Roninson, Igor B (2002) Oncogenic functions of tumour suppressor p21(Waf1/Cip1/Sdi1): association with cell senescence and tumour-promoting activities of stromal fibroblasts. Cancer Lett 179:1-14

Showing the most recent 10 out of 14 publications