To identify protein kinases with functional somatic mutations that contribute to the process of tumorigenesis, protein kinases newly implicated in cancer through the presence of putative driver mutations identified in recent cancer genome sequencing efforts will be characterized. Initially, the focus will be on four such kinases, DAPK3, SGK085 and MLK4, which score highly in the devised ranking system as being the most likely to play a role in cancer, and protein kinase C family members. In vitro and in vivo analysis of kinase activity will be carried out in order to determine whether individual mutations in DAPK3, SGK085 and MLK4 increase or decrease activity, attempt to identify substrates for the mutant and WT kinases and define in what signaling pathway(s) they act, and determine the effects of expressing mutant and WT kinases in normal and cancer cells, assaying for changes in proliferation, cell cycle progression, apoptosis and autophagy, morphological transformation, anchorage independent growth in soft agar, and tumorigenesis in nude mice. This will define whether each mutant kinase has gain- or loss-of-function mutations, whether it acts as an oncoprotein or opposes the effects of its normal tumor suppressor kinase counterpart, and whether the kinase might serve as a new drug target for cancer therapy. The protein kinase C (PKC) family of kinases has been extensively studied in cancer, through their role as receptors for tumor promoting chemicals, but few cancer mutations have been identified, and there is a debate regarding whether activation or inactivation of PKC family of kinases is important for cancer. The discovery of nonsynonymous point mutations in many PKCs, mainly in colorectal cancer (CRC) and glioblastoma multiforme (GBM), provides an opportunity to determine if PKCs are activated or inactivated in cancer and determine how these mutations contribute to tumorigenesis. Mutations observed in the PKC family of isozymes in cancer utilizing live-cell imaging techniques will be characterized. Additionally, all the PKC mutations we are studying in CRC occur in the context of activating K-Ras mutations. K-Ras is a substrate for PKC, and phosphorylation of K-Ras by PKC alters its subcellular targeting and causes K-Ras to promote apoptosis. The intention is to determine if loss of function mutations in PKC can promote the survival of colon cancer cells harboring K-Ras mutations, by suppressing this K-Ras-induced apoptotic feedback loop, thereby fine-tuning oncogenic K-Ras addiction. An investigation of the mutations in the atypical PKC, aPKC6, in GBM will be carried out to determine their effect on the activity of aPKC6 using similar approaches and their transforming potential will be tested in a new mouse model for GBM.

Public Health Relevance

The studies proposed in this application seek to elucidate how protein kinases that have been newly implicated in cancer through cancer genome sequencing act in the initiation and maintenance of cancer phenotypes, with the ultimate goal of identifying protein kinases and pathways that may offer the possibility of defining new cancer therapeutic targets.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA082683-13
Application #
8255344
Study Section
Intercellular Interactions (ICI)
Program Officer
Yassin, Rihab R,
Project Start
1999-07-01
Project End
2015-04-30
Budget Start
2012-05-01
Budget End
2013-04-30
Support Year
13
Fiscal Year
2012
Total Cost
$673,847
Indirect Cost
$320,122
Name
Salk Institute for Biological Studies
Department
Type
DUNS #
078731668
City
La Jolla
State
CA
Country
United States
Zip Code
92037
Zheng, Xinde; Boyer, Leah; Jin, Mingji et al. (2016) Alleviation of neuronal energy deficiency by mTOR inhibition as a treatment for mitochondria-related neurodegeneration. Elife 5:
Marusiak, Anna A; Stephenson, Natalie L; Baik, Hayeon et al. (2016) Recurrent MLK4 Loss-of-Function Mutations Suppress JNK Signaling to Promote Colon Tumorigenesis. Cancer Res 76:724-35
Zheng, Xinde; Boyer, Leah; Jin, Mingji et al. (2016) Metabolic reprogramming during neuronal differentiation from aerobic glycolysis to neuronal oxidative phosphorylation. Elife 5:
Li, Xinjian; Jiang, Yuhui; Meisenhelder, Jill et al. (2016) Mitochondria-Translocated PGK1 Functions as a Protein Kinase to Coordinate Glycolysis and the TCA Cycle in Tumorigenesis. Mol Cell 61:705-19
Puto, Lorena A; Brognard, John; Hunter, Tony (2015) Transcriptional Repressor DAXX Promotes Prostate Cancer Tumorigenicity via Suppression of Autophagy. J Biol Chem 290:15406-20
Tian, Ruijun; Wang, Haopeng; Gish, Gerald D et al. (2015) Combinatorial proteomic analysis of intercellular signaling applied to the CD28 T-cell costimulatory receptor. Proc Natl Acad Sci U S A 112:E1594-603
Wilkinson, Deepti S; Jariwala, Jinel S; Anderson, Ericka et al. (2015) Phosphorylation of LC3 by the Hippo kinases STK3/STK4 is essential for autophagy. Mol Cell 57:55-68
Heimbucher, Thomas; Liu, Zheng; Bossard, Carine et al. (2015) The Deubiquitylase MATH-33 Controls DAF-16 Stability and Function in Metabolism and Longevity. Cell Metab 22:151-63
Fuhs, Stephen Rush; Meisenhelder, Jill; Aslanian, Aaron et al. (2015) Monoclonal 1- and 3-Phosphohistidine Antibodies: New Tools to Study Histidine Phosphorylation. Cell 162:198-210
Antal, Corina E; Hudson, Andrew M; Kang, Emily et al. (2015) Cancer-associated protein kinase C mutations reveal kinase's role as tumor suppressor. Cell 160:489-502

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