Our long term goals are to understand the molecular mechanisms underlying glioblastoma multiforme, the most common and deadly among human brain tumors. The EGF receptor has been strongly implicated and much research on its downstream signaling has focused on the ERK signaling module. Unexpectedly, our work has instead led us to study a pathway not commonly considered downstream of the EGF receptor or in tumorigenesis, the JNK pathway. We have found that 86 percent of primary glioblastoma tumors show activation of a 54 kDa JNK isoform. EGF induces strong JNK activation in 69 percent of cell lines derived from glioblastoma tumors but only weak activation was observed in 6 normal cell lines. Further work in two tumor cell lines has indicated that JNK is important for anchorage independent growth and the prevention of apoptosis. We hypothesize that an important difference between glioblastoma tumors and normal tissues is that EGF receptor signals are also directed towards the JNK pathway. The goals of this application are to further study the mechanisms by which JNK becomes activated and how it contributes to multiple phenotypes.
In Specific Aim #1, we will examine the mechanisms underlying the enhanced EGF induced activation of JNK seen in glioblastoma cell lines. Several points at which signals can be directed towards the JNK signaling module will be examined: 1) the small GTPases, Rac and Cdc42; 2) PI 3-kinase; and 3) Gab1. These molecules will be tested for increased activity/binding following EGF addition in glioblastoma cell lines as compared to normal astrocyte cell lines. Dominant negative versions of these molecules will be used to confirm their roles in JNK activation.
In Specific Aim #2, we will determine which JNK isoform the 54 kDa form corresponds to using RNase protection. Next, we will identify the mechanisms by which it became preferentially phosphorylated. Most importantly, we will determine what properties this isoform has that might contribute to tumorigenesis. The localization of the 54 kDa isoform will be studied in tumor sections and the transcription factors that bind to this isoform in tumors will also be studied.
In Specific Aim #3, we will evaluate the relative contribution of JNK and ERK to glial tumorigenesis. The notion that JNK contributes to tumorigenesis is relatively new and not well studied, especially in animal models, but there is a much more extensive literature on the contribution of ERK to tumorigenesis. Thus, we will attempt to clarify the relative contribution of these two signaling modules to these critical phenotypes in vivo: 1) tumor formation in athymic mice, 2) angiogenesis, 3) cell proliferation, and 4) prevention of apoptosis. This work will further enhance our knowledge of this novel signaling pathway in this human cancer and provide new avenues for diagnostics and therapeutics.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
1R01CA096539-01
Application #
6503341
Study Section
Special Emphasis Panel (ZRG1-CPA (03))
Program Officer
Jhappan, Chamelli
Project Start
2002-04-01
Project End
2007-03-31
Budget Start
2002-04-01
Budget End
2003-03-31
Support Year
1
Fiscal Year
2002
Total Cost
$314,393
Indirect Cost
Name
Thomas Jefferson University
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
061197161
City
Philadelphia
State
PA
Country
United States
Zip Code
19107
Piccione, E C; Lieu, T J; Gentile, C F et al. (2012) A novel epidermal growth factor receptor variant lacking multiple domains directly activates transcription and is overexpressed in tumors. Oncogene 31:2953-67
Nitta, R T; Del Vecchio, C A; Chu, A H et al. (2011) The role of the c-Jun N-terminal kinase 2-?-isoform in non-small cell lung carcinoma tumorigenesis. Oncogene 30:234-44
Li, Gordon; Mitra, Siddhartha; Wong, Albert J (2010) The epidermal growth factor variant III peptide vaccine for treatment of malignant gliomas. Neurosurg Clin N Am 21:87-93
Li, Gordon; Mitra, Siddhartha; Karamchandani, Jason et al. (2010) Pineal parenchymal tumor of intermediate differentiation: clinicopathological report and analysis of epidermal growth factor receptor variant III expression. Neurosurgery 66:963-8; discussion 968
Nitta, Ryan T; Badal, Shawn S; Wong, Albert J (2010) Measuring the constitutive activation of c-Jun N-terminal kinase isoforms. Methods Enzymol 484:531-48
Cui, Jian; Han, Shuang-Yin; Wang, Congli et al. (2006) c-Jun NH(2)-terminal kinase 2alpha2 promotes the tumorigenicity of human glioblastoma cells. Cancer Res 66:10024-31
Cui, Jian; Holgado-Madruga, Marina; Su, Wanwen et al. (2005) Identification of a specific domain responsible for JNK2alpha2 autophosphorylation. J Biol Chem 280:9913-20
Holgado-Madruga, Marina; Wong, Albert J (2004) Role of the Grb2-associated binder 1/SHP-2 interaction in cell growth and transformation. Cancer Res 64:2007-15
Tsuiki, Hiromasa; Tnani, Mehdi; Okamoto, Isamu et al. (2003) Constitutively active forms of c-Jun NH2-terminal kinase are expressed in primary glial tumors. Cancer Res 63:250-5
Holgado-Madruga, Marina; Wong, Albert J (2003) Gab1 is an integrator of cell death versus cell survival signals in oxidative stress. Mol Cell Biol 23:4471-84