Pro-inflammatory prostaglandin E2 (PGE2) is the most abundant prostaglandin found in human colorectal cancers and plays a predominant role in promoting tumor growth. In contrast to the role of PGE2 in carcinogenesis and inflammation, another of the arachidonate-based bioactive lipids, endocannabinoids, exert potential anti-tumor effects on a wide spectrum of human tumors in vitro and have proven antiinflammatory properties. Opposing effects of PGE2 and endocannabinoids on inflammation and cancer progression prompted us to hypothesize that PGE2 and endocannabinoids coordinately control tumor progression. Endocannabinoids primarily activate two G-protein-coupled cannabinoid receptors CBI and CB2 and are degraded by fatty acid amide hydrolase (FAAH). Based on our preliminary data, cross talk exists between PGE2 and endocannabinoid signaling. PGE2 can downregulate CBI expression via DNA methylation, whereas a selective COX-2 inhibitor restores CBI expression. However, little is known regarding the role of CB1, CB2 and FAAH in colorectal cancer progression. This proposal will examine the following: 1) The role of PGE2 in silencing tumor suppressors, DNA repair genes, and tumor inhibitory genes via DNA methylation during the colon tumor progression. 2) The role of endocannabinoid signaling in colorectal cancer progression by examining the biological functions of FAAH and by evaluating whether a combinational treatment of a CB1 agonist with a demethylating agent or a selective COX-2 inhibitor achieves optimal anti-tumor effects of CBI agonists in vivo. 3) The influence of endocannabinoid signaling on inflammation-associated colorectal tumorigenesis by defining the role of CB1, CB2 and FAAH in the mouse models of inflammation-associated colonic carcinogenesis and by evaluating the relative contributions of the endocannabinoid signaling in epithelial cells versus immune cells. In summary, we expect to generate novel mouse models and new approaches to study the role of PGE2-mediated inflammation, its influence on DNA methylation and suppression of the anti-inflammatory role of the endocannabinoid pathway in the progression of colorectal cancer.

Public Health Relevance

The most important aspect of both PGE2 and endocannabinoid signaling is that they have opposing effects on inflammation and carcinogenesis. PGE2 promotes inflammation and cancer progression, whereas the endocannabinoids inhibit inflammation and tumor growth. Understanding how two pathways orchestrate tumor progression will provide a significant advance in the cancer field.

National Institute of Health (NIH)
National Cancer Institute (NCI)
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University of Texas MD Anderson Cancer Center
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Hsu, Alice H; Lum, Michelle A; Shim, Kang-Sup et al. (2018) Crosstalk between PKC? and PI3K/AKT Signaling Is Tumor Suppressive in the Endometrium. Cell Rep 24:655-669
Liang, Xiaohuan; Daikoku, Takiko; Terakawa, Jumpei et al. (2018) The uterine epithelial loss of Pten is inefficient to induce endometrial cancer with intact stromal Pten. PLoS Genet 14:e1007630
Wang, Dingzhi; DuBois, Raymond N (2018) Role of prostanoids in gastrointestinal cancer. J Clin Invest 128:2732-2742
Yuan, Jia; Deng, Wenbo; Cha, Jeeyeon et al. (2018) Tridimensional visualization reveals direct communication between the embryo and glands critical for implantation. Nat Commun 9:603
Mendelson, Karen; Pandey, Suveg; Hisano, Yu et al. (2017) The ceramide synthase 2b gene mediates genomic sensing and regulation of sphingosine levels during zebrafish embryogenesis. Elife 6:
Yanagida, Keisuke; Hla, Timothy (2017) Vascular and Immunobiology of the Circulatory Sphingosine 1-Phosphate Gradient. Annu Rev Physiol 79:67-91
Cha, Jeeyeon; Dey, Sudhansu K (2017) Hunting for Fox(A2): Dual roles in female fertility. Proc Natl Acad Sci U S A 114:1226-1228
Wang, Dingzhi; Sun, Haiyan; Wei, Jie et al. (2017) CXCL1 Is Critical for Premetastatic Niche Formation and Metastasis in Colorectal Cancer. Cancer Res 77:3655-3665
Sones, Jenny L; Cha, Jeeyeon; Woods, Ashley K et al. (2016) Decidual Cox2 inhibition improves fetal and maternal outcomes in a preeclampsia-like mouse model. JCI Insight 1:
Yuan, Jia; Cha, Jeeyeon; Deng, Wenbo et al. (2016) Planar cell polarity signaling in the uterus directs appropriate positioning of the crypt for embryo implantation. Proc Natl Acad Sci U S A 113:E8079-E8088

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