Numerous human tumor lines do not express the HLA class II antigen presenting molecules in response to IFN-gamma (interferon-gamma), a defect that may be related to tumor cell escape of anti-tumor immunity. In some cases, this defect has been attributed to loss of the retinoblastoma protein. In many other cases, lack of HLA class II induction is attributable to lack of induction of class II transactivator (CIITA), which is required for HLA class II activation by IFN-gamma. In some cases, CIITA noninducible pancreatic tumor lines are defective in the function of interferon regulatory factor-2 (IRF-2). Preliminary studies for this proposal strongly indicate that IRF-2 is important for the production of CIITA, and in particular that IRF-2 function involves cooperation with yet another factor, IRF-1, previously implicated in the production of CIITA. This proposal is designed to understand the molecular basis for why IRF-1 and IRF-2 cooperate to effect the IFN-gamma response of the CIITA promoter. The proposal will also investigate the basis for lack of IRF-2 DNA binding function in human pancreatic tumor lines, as well as other IRF-2/CIITA related anomalies seen in several other tumors lines. Results from this work will provide a better understanding of how multiple factors interact to effect gene activation. In particular, this work will help resolve the bases for functional differences between the closely related transactivators, IRF-1 and IRF-2, and their response elements. In the case of the response elements, this work will likely establish that minor differences generally considered to be irrelevant variations of a """"""""uni-functional"""""""" consensus sequence actually have important functional consequences. This proposal also will likely lead to a better understanding of gene regulation relevant to autoimmunity and tumorigenesis. It is also likely that this work will identify mutations in IRF-2 that could serve as pancreatic tumor markers. If so, this would be the first demonstration of a role for IRF-2 mutations in human tumor. Methods: EMSA, in vivo footprinting, DNA transfection, DNA sequencing, DNA cloning.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA081497-04
Application #
6513575
Study Section
Pathology B Study Section (PTHB)
Program Officer
Mccarthy, Susan A
Project Start
1999-05-01
Project End
2004-02-29
Budget Start
2002-03-21
Budget End
2004-02-29
Support Year
4
Fiscal Year
2002
Total Cost
$211,016
Indirect Cost
Name
University of South Florida
Department
Biochemistry
Type
Schools of Medicine
DUNS #
City
Tampa
State
FL
Country
United States
Zip Code
33612
Mohapatra, S; Park, S J; Boyapalle, S et al. (2009) Human respiratory syncytial virus reduces the number of cells in S-phase and increases GADD153 expression in HEp-2 cells. Acta Virol 53:207-11
Palubin, Kimberly M; Goodwin, Bonnie L; Niesen, Melissa I et al. (2006) A direct mechanistic link between growth control and a tumor cell immune function: increased interleukin-8 secretion accounts for elimination of Oct-1 antisense transformants from scid mice. Anticancer Res 26:1733-8
Osborne, Aaron R; Zhang, Hongquan; Blanck, George (2006) Oct-1 DNA binding activity unresponsive to retinoblastoma protein expression prevents MHC class II induction in a non-small cell lung carcinoma cell line. Mol Immunol 43:710-6
Niesen, Melissa I; Osborne, Aaron R; Yang, Hua et al. (2005) Activation of a methylated promoter mediated by a sequence-specific DNA-binding protein, RFX. J Biol Chem 280:38914-22
Le, Elizabeth; Zhang, Hongquan; Blanck, George (2005) CIITA transformation rescues the apoptotic function of MHC class II in melanoma cells. Anticancer Res 25:3889-92
Osborne, Aaron R; Zhang, Hongquan; Fejer, Gyorgy et al. (2004) Oct-1 maintains an intermediate, stable state of HLA-DRA promoter repression in Rb-defective cells: an Oct-1-containing repressosome that prevents NF-Y binding to the HLA-DRA promoter. J Biol Chem 279:28911-9
Eason, Donna D; LeBron, Cynthia; Coppola, Domenico et al. (2003) Development of CD30+ lymphoproliferative disease in mice lacking interferon regulatory factor-1. Oncogene 22:6166-76
Xi, Hongkang; Blanck, George (2003) The IRF-2 DNA binding domain facilitates the activation of the class II transactivator (CIITA) type IV promoter by IRF-1. Mol Immunol 39:677-84
Goodwin, B L; Xi, H; Tejiram, R et al. (2001) Varying functions of specific major histocompatibility class II transactivator promoter III and IV elements in melanoma cell lines. Cell Growth Differ 12:327-35
Osborne, A; Zhang, H; Yang, W M et al. (2001) Histone deacetylase activity represses gamma interferon-inducible HLA-DR gene expression following the establishment of a DNase I-hypersensitive chromatin conformation. Mol Cell Biol 21:6495-506

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