An agonist that binds to a GPR55 receptor is a compound or drug that binds to the receptor and produces an expected effect (see below).
GPR55 Agonism Associated Effects
GPR55/LPI and Cancer
GPR55/LPI axis is considered a novel target for cancer therapeutics (R. Ross, 2011).1
GPR55 overexpression has been associated with cancer metastasis in specific tumors such as acute myeloid leukemia, uveal melanoma, low-grade glioma, and renal cancer. Furthermore, the LPI/GPR55 axis has been reported to participate in several pro-oncogenic processes, such as cellular proliferation, differentiation, migration, invasion, and metastasis (A. Calvillo-Robledo et al., 2022).2
GPR55/LPI may play an essential role in the metastasis of breast cancer cells (L. Ford et al., 2010).3
Cancer cells may be able to hijack the motility-related activity of GPR55 and increase LPI production, both associated with metastasis (A. Wnorowski et al., 2021).4
Expression of GPR55 is increased in endometrial carcinoma (T. Ayakannu et al., 2021).5
The reader is reminded that THC is an agonist at GPR55 while CBD is an antagonist at the same receptor with potential practical relevance in the clinical oncology setting.
GPR55/LPI and Other Conditions
GPR55/LPI axis also potentially influences obesity (J. Moreno-Navarrete et al., 2012).6
More specifically, activation of the LPI/GPR55 axis may contribute to the underlying pathology of obesity-induced inflammation (M. Kurano et al., 2021).7 Also, GPR55 plays a role in descending pain modulation associated with inflammatory pains (H. Blanton et al., 2022).8
GPR55 affects osteoclast and osteoblast differentiation associated with the development of bone mass (L. Whyte et al., 2009)9 with potential relevance to antagonists in treating osteoporosis.
In 2009 another UK team found that lysophosphatidylinositol (LPI) was a potent and efficacious ligand at GPR55 (C. Henstridge et al., 2009).10
Strong GPR55 agonists (E. Ryberg et al., 2007)11
- 2-AG EC50 ~2nM
- Anandamide EC50 ~18nM
- CP55940 ~5nM
- Noladin ether ~10nM
- Palmitoylethanolamide (PEA) ~4nM
- THC EC50 ~8nM
- Virodhamine EC50 ~12nM