In this application, we propose studies that will enable us to retrieve cancer cells that are hypoxic and/or cycling from tumor xenografts using our newly developed pair of fluorescent protein reporter system that we engineered and termed HypoxCR (Hypoxia - cell Cycle Reporters). With HypoxCR, we will study a panel of human cancer cell lines in vitro and in vivo to characterize their genomic and metabolic reprogramming upon exposure to hypoxia in vitro or in tumor xenografts. The delineation of the genomic and metabolic programs of the subpopulations of cancer cells in a tumor will instruct us about the commensal relations amongst cancer cells in a tumor tissue and lead us to novel therapeutic targets in addition to candidates that we identified from Myc and/or HIF targets, such as lactate dehydrogenase A (LDHA) and glutatminase (GLS). Our long term goal is to identify molecular targets from the reprogramming of cancer cells in the tumor tissue and find potential drug-like inhibitors of these targets as experimental molecular probes and potential therapeutic agents. To reach our goals, we set the following Aims:
Aim 1. To characterize cancer cells in the tumor microenvironment with a novel dual fluorescent protein reporter system for hypoxia and cell cycling (HypoxCR). Using this double reporter system, we propose to retrieve cancer cells from different subpopulations of the tumor xenograft to characterize their genomic changes and phenotypes and compare these changes with those arising in vitro under hypoxia.
Aim 2. To delineate the genomic reprogramming of cancer cells by MYC and HIF-1 in vitro and in vivo. Using in vitro models of tumor hypoxia and cells retrieved from xenografts marked by HypoxCR, we will use high throughput microarray-based methods to delineate the genomic reprogramming of cells by MYC and HIF-1 in the tumor microenvironment.
Aim3. To determine the role of key nodal points in metabolic reprogramming of cancer cells in hypoxia and in the tumor microenvironment. We propose to study miR-23a/b (which is suppressed by Myc and regulates glutaminase protein levels) and MCT1 (monocarboxylate/lactate transporter) in the reprogramming of cancer cells in the tumor microenvironment.
Aim 4. To determine the effects of inhibitors of key metabolic nodes in cancer cells in vitro and in vivo. We propose to use fluorescent HypoxCR reporters to determine the sensitivity of subpopulations of tumor cells to therapy in vivo and establish complementation between drug-like molecules (eg., LDHA and GLS inhibitors) that target different tumor cell subpopulations.
Tumors are a mixture of cancer cells with variable characteristics that resist therapies. We will use a new way of retrieving subpopulations of cancer cells from tumors and determine their sensitivities to specific therapies, informing strategic combination therapy targeting metabolism.
|Doherty, Joanne R; Yang, Chunying; Scott, Kristen E N et al. (2014) Blocking lactate export by inhibiting the Myc target MCT1 Disables glycolysis and glutathione synthesis. Cancer Res 74:908-20|
|Le, Anne; Stine, Zachary E; Nguyen, Christopher et al. (2014) Tumorigenicity of hypoxic respiring cancer cells revealed by a hypoxia-cell cycle dual reporter. Proc Natl Acad Sci U S A 111:12486-91|
|Stine, Zachary E; Dang, Chi V (2013) Stress eating and tuning out: cancer cells re-wire metabolism to counter stress. Crit Rev Biochem Mol Biol 48:609-19|
|Le, Anne; Lane, Andrew N; Hamaker, Max et al. (2012) Glucose-independent glutamine metabolism via TCA cycling for proliferation and survival in B cells. Cell Metab 15:110-21|
|Ji, Hongkai; Wu, George; Zhan, Xiangcan et al. (2011) Cell-type independent MYC target genes reveal a primordial signature involved in biomass accumulation. PLoS One 6:e26057|
|Dang, Chi V (2010) Rethinking the Warburg effect with Myc micromanaging glutamine metabolism. Cancer Res 70:859-62|
|Seltzer, Meghan J; Bennett, Bryson D; Joshi, Avadhut D et al. (2010) Inhibition of glutaminase preferentially slows growth of glioma cells with mutant IDH1. Cancer Res 70:8981-7|
|Yustein, Jason T; Liu, Yen-Chun; Gao, Ping et al. (2010) Induction of ectopic Myc target gene JAG2 augments hypoxic growth and tumorigenesis in a human B-cell model. Proc Natl Acad Sci U S A 107:3534-9|
|Fan, Jinshui; Zeller, Karen; Chen, Yu-Chi et al. (2010) Time-dependent c-Myc transactomes mapped by Array-based nuclear run-on reveal transcriptional modules in human B cells. PLoS One 5:e9691|
|Dang, Chi V (2010) Enigmatic MYC Conducts an Unfolding Systems Biology Symphony. Genes Cancer 1:526-531|
Showing the most recent 10 out of 61 publications