The proposal will elucidate critical regulators of the TRAIL signaling pathway that determine the exquisite sensitivity of 4/7 pediatric rhabdomyosarcomas (RMS) to TRAIL-induced cytotoxicity and apoptosis at concentrations < 1 ng/ml. All cultured cell lines express high levels of receptor DR5, but not DR4 or the decoy receptors DcR1 or DcR2, and express FADD and procaspase-8, with the exception of Rh36. Expression of c-FLIP is high in TRAIL-sensitive and -resistant lines, thereby not correlating directly with TRAIL sensitivity. Expression of procaspases-8 and -10 is highest in TRAIL-sensitive RD, Rh1 and Rh30. TRAIL-sensitive Rh18 expresses procaspase-8 in the absence of procaspase-10 and c-FLIP, and procaspase-10 is not expressed in TRAIL-resistant Rh41. Based upon these cellular characteristics the following hypotheses will be tested: 1) Following ligation of TRAIL to DR5, a DISC is formed among DR5, FADD, procaspase-8 and c-FLIP in RMS cell lines resulting in type I (direct) or type II (mitochondria- and procaspase-10- dependent) cell death, and 2) TRAIL resistance in Rh41 is due to deficiency in caspase-10. The second focus is to elucidate agents that can sensitize TRAIL- resistant RMS to TRAIL, or that can elicit synergistic interactions with TRAIL. Combination of TRAIL with actinomycin-D or doxorubicin has demonstrated > additive effects in TRAIL-sensitive RMS lines, and with recombinant human interferon-gamma (IFN-gamma) has induced cytotoxic response in TRAIL-resistant HT29 human .colon carcinoma cells. We will therefore test the following hypotheses: 1) TRAIL- resistant Rh28 and Rh41 can be sensitized to TRAIL by cycloheximide, actinomycin-D or IFN-gamma, and 2) specific chemotherapeutic agents can be identified that elicit synergistic interactions with TRAIL in TRAIL-sensitive RMS cell lines. Thirdly, we will test the hypothesis that TRAIL induces antitumor responses in human RMS xenografts when administered alone, or in combination with chemotherapeutic agents based upon data derived in tissue culture. The long-term objectives of the proposal are to develop highly effective therapy for metastatic disease in pediatric RMS from: 1) understanding specific signaling pathways involved in the regulation of cell death and apoptosis, 2) the identification of new molecular targets, and 3) developing new therapeutic strategies based upon specific molecular characteristics.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA087952-04
Application #
6719538
Study Section
Experimental Therapeutics Subcommittee 1 (ET)
Program Officer
Forry, Suzanne L
Project Start
2001-03-09
Project End
2006-02-28
Budget Start
2004-03-01
Budget End
2005-02-28
Support Year
4
Fiscal Year
2004
Total Cost
$249,000
Indirect Cost
Name
St. Jude Children's Research Hospital
Department
Type
DUNS #
067717892
City
Memphis
State
TN
Country
United States
Zip Code
38105
Mazumdar, Tapati; Sandhu, Ranjodh; Qadan, Maha et al. (2013) Hedgehog signaling regulates telomerase reverse transcriptase in human cancer cells. PLoS One 8:e75253
Phillips, Darren C; Martin, Sophie; Doyle, Belinda T et al. (2007) Sphingosine-induced apoptosis in rhabdomyosarcoma cell lines is dependent on pre-mitochondrial Bax activation and post-mitochondrial caspases. Cancer Res 67:756-64
Phillips, D C; Hunt, J T; Moneypenny, C G et al. (2007) Ceramide-induced G2 arrest in rhabdomyosarcoma (RMS) cells requires p21Cip1/Waf1 induction and is prevented by MDM2 overexpression. Cell Death Differ 14:1780-91
Nagy, Katalin; Szekely-Szuts, Kinga; Izeradjene, Kamel et al. (2006) Proteasome inhibitors sensitize colon carcinoma cells to TRAIL-induced apoptosis via enhanced release of Smac/DIABLO from the mitochondria. Pathol Oncol Res 12:133-42
Bois, Philippe R J; Izeradjene, Kamel; Houghton, Peter J et al. (2005) FOXO1a acts as a selective tumor suppressor in alveolar rhabdomyosarcoma. J Cell Biol 170:903-12
Nagy, Katalin; Petak, Istvan; Imre, Gergely et al. (2005) Proteasome inhibitors abolish cell death downstream of caspase activation during anti-microtubule drug-induced apoptosis in leukemia cells. Anticancer Res 25:3321-6
Izeradjene, Kamel; Douglas, Leslie; Delaney, Addison B et al. (2004) Casein kinase I attenuates tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis by regulating the recruitment of fas-associated death domain and procaspase-8 to the death-inducing signaling complex. Cancer Res 64:8036-44
Izeradjene, Kamel; Douglas, Leslie; Delaney, Addison et al. (2004) Influence of casein kinase II in tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis in human rhabdomyosarcoma cells. Clin Cancer Res 10:6650-60
Petak, I; Vernes, R; Szucs, K S et al. (2003) A caspase-8-independent component in TRAIL/Apo-2L-induced cell death in human rhabdomyosarcoma cells. Cell Death Differ 10:729-39