Allelic deletions of 18q affect 90 percent of pancreatic cancers, but the target was unknown. The mapping of homozygous deletions, assembled as preliminary data for this grant application, uncovered a novel gene, DPC4. Initial studies showed that at least half of pancreatic cancers harbor inactivating genetic alterations of DPC4. DPC4 was homozygously deleted in 30 percent of pancreatic tumors. Point mutations that would cause gross disruption or malfunction of the gene product were seen in nearly a quarter of additional pancreatic tumors. Other tumor systems appear to have a lower rate of DPC4 mutation than that found in pancreatic cancer. DPC4 has no recognizable peptide motifs, but the function of DPC4 was suggested by strong sequence similarities to Drosophila and C. elegans genes involved in TGF-beta superfamily pathways. The studies outliend in this proposal will extend these results at the 18q homozygous deletion site. They will: 1) Determine the gene structure and genetic alterations of DPC4. This will include cloning of the non-coding regions, determination of regions of evolutionary conservation, and the comparison of mutations in pancreatic and other human tumor types. 2) Determine the expression patterns and biochemical interactions of DPC4 gene products. This will include the development of antibodies, the patterns of DPC4 expression in developing, adult, and neoplastic tissues, the exploration of various biochemical properties, and the identification of interacting proteins. 3) Analyze the biological function of DPC4 in normal, engineered, and cancer cells. This will include the manipulation of DPC4 expression in various cell types, observation of phenotypic effects, and the evaluation of responsiveness to TGF-beta superfamily members. A knockout mouse model will be developed, and murine and human cells having differing DPC4 genotypes will be compared.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
1R01CA068228-01A2
Application #
2008954
Study Section
Pathology B Study Section (PTHB)
Project Start
1997-01-15
Project End
2001-12-31
Budget Start
1997-01-15
Budget End
1997-12-31
Support Year
1
Fiscal Year
1997
Total Cost
Indirect Cost
Name
Johns Hopkins University
Department
Pathology
Type
Schools of Medicine
DUNS #
045911138
City
Baltimore
State
MD
Country
United States
Zip Code
21218
Gallmeier, Eike; Kern, Scott E (2005) Absence of specific cell killing of the BRCA2-deficient human cancer cell line CAPAN1 by poly(ADP-ribose) polymerase inhibition. Cancer Biol Ther 4:703-6
Gallmeier, Eike; Winter, Jordan M; Cunningham, Steven C et al. (2005) Novel genotoxicity assays identify norethindrone to activate p53 and phosphorylate H2AX. Carcinogenesis 26:1811-20
van der Heijden, Michiel S; Brody, Jonathan R; Dezentje, David A et al. (2005) In vivo therapeutic responses contingent on Fanconi anemia/BRCA2 status of the tumor. Clin Cancer Res 11:7508-15
Iacobuzio-Donahue, Christine A; Song, Jason; Parmiagiani, Giovanni et al. (2004) Missense mutations of MADH4: characterization of the mutational hot spot and functional consequences in human tumors. Clin Cancer Res 10:1597-604
Hempen, Paula M; Zhang, Lin; Bansal, Ravi K et al. (2003) Evidence of selection for clones having genetic inactivation of the activin A type II receptor (ACVR2) gene in gastrointestinal cancers. Cancer Res 63:994-9
Ryu, Byungwoo; Kern, Scott E (2003) The essential similarity of TGFbeta and activin receptor transcriptional responses in cancer cells. Cancer Biol Ther 2:164-70
Sohn, Taylor A; Bansal, Ravi; Su, Gloria H et al. (2002) High-throughput measurement of the Tp53 response to anticancer drugs and random compounds using a stably integrated Tp53-responsive luciferase reporter. Carcinogenesis 23:949-57
Su, G H; Bansal, R; Murphy, K M et al. (2001) ACVR1B (ALK4, activin receptor type 1B) gene mutations in pancreatic carcinoma. Proc Natl Acad Sci U S A 98:3254-7
Montgomery, E; Goggins, M; Zhou, S et al. (2001) Nuclear localization of Dpc4 (Madh4, Smad4) in colorectal carcinomas and relation to mismatch repair/transforming growth factor-beta receptor defects. Am J Pathol 158:537-42
Wilentz, R E; Su, G H; Dai, J L et al. (2000) Immunohistochemical labeling for dpc4 mirrors genetic status in pancreatic adenocarcinomas : a new marker of DPC4 inactivation. Am J Pathol 156:37-43

Showing the most recent 10 out of 17 publications