Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P21554 (cannabinoid receptor)
 3,582 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have earlier reported overexpression of the central and peripheral cannabinoid receptors CB1 and CB2 in mantle cell lymphoma (MCL), a B cell non-Hodgkin lymphoma. In this study, treatment with cannabinoid receptor ligands caused a decrease in viability of MCL cells, while control cells lacking CB1 were not affected. Interestingly, equipotent doses of the CB1 antagonist SR141716A and the CB1/CB2 agonist anandamide inflicted additive negative effects on viability. Moreover, treatment with the CB1/CB2 agonist Win-55,212-2 caused a decrease in long-term growth of MCL cells in culture. Induction of apoptosis, as measured by FACS/Annexin V-FITC, contributed to the growth suppressive effect of Win-55,212-2. Our data suggest that cannabinoid receptors may be considered as potential therapeutic targets in MCL.
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PMID:Cannabinoid receptor ligands mediate growth inhibition and cell death in mantle cell lymphoma. 1633 99

We have recently shown that cannabinoids induce growth inhibition and apoptosis in mantle cell lymphoma (MCL), a malignant B-cell lymphoma that expresses high levels of cannabinoid receptor types 1 and 2 (CB(1) and CB(2)). In the current study, the role of each receptor and the signal transduction triggered by receptor ligation were investigated. Induction of apoptosis after treatment with the synthetic agonists R(+)-methanandamide [R(+)-MA] and Win55,212-2 (Win55; (R)-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinylmethyl) pyrrolo-[1,2,3-d,e]-1,4-benzoxazin-6-yl]-1-naphthalenyl-methanone) was dependent on both cannabinoid receptors, because pretreatment with N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboximide hydrochloride (SR141716A) and N-((1S)-endo-1,3,3-trimethyl bicyclo heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide) (SR144528), specific antagonists to CB(1) and CB(2), respectively, abrogated caspase-3 activity. Preincubation with the inhibitors 4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)1H-imidazole (SB203580) and 4-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)-1H-imidazole (SB202190) showed that phosphorylation of MAPK p38 was implicated in the signal transduction leading to apoptosis. Treatment with R(+)-MA and Win55 was associated with accumulation of ceramide, and pharmacological inhibition of ceramide synthesis de novo prevented both p38 activation and mitochondria depolarization assessed by binding of 3,3'-dihexyloxacarbocyanine iodide (DiOC(6)). In contrast, the pancaspase inhibitor z-Val-Ala-Asp(Ome)-CH(2)F (z-VAD-FMK) did not protect the mitochondrial integrity. Taken together, these results suggest that concurrent ligation of CB(1) and CB(2) with either R(+)-MA or Win55 induces apoptosis via a sequence of events in MCL cells: accumulation of ceramide, phosphorylation of p38, depolarization of the mitochondrial membrane, and caspase activation. Although induction of apoptosis was observed in both MCL cell lines and primary MCL, normal B cells remained unaffected. The present data suggest that targeting CB(1)/CB(2) may have therapeutic potential for the treatment of mantle cell lymphoma.
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PMID:Cannabinoid receptor-mediated apoptosis induced by R(+)-methanandamide and Win55,212-2 is associated with ceramide accumulation and p38 activation in mantle cell lymphoma. 1693 28

Endogenous and synthetic cannabinoids exert antiproliferative and proapoptotic effects in various types of cancer and in mantle cell lymphoma (MCL). In this study, we evaluated the expression of cannabinoid receptors type 1 and type 2 (CB1 and CB2) in non-Hodgkin lymphomas of B cell type (n = 62). A majority of the lymphomas expressed higher mRNA levels of CB1 and/or CB2 as compared to reactive lymphoid tissue. With the exception of MCL, which uniformly overexpresses both CB1 and CB2, the levels of cannabinoid receptors within other lymphoma entities were highly variable, ranging from 0.1 to 224 times the expression in reactive lymph nodes. Low levels of the splice variant CB1a, previously shown to have a different affinity for cannabinoids than CB1, were detected in 44% of the lymphomas, while CB1b expression was not detected. In functional studies using MCL, Burkitt lymphoma (BL), chronic lymphatic leukemia (CLL) and plasma cell leukemia cell lines, the stable anandamide analog R(+)-methanandamide (R(+)-MA) induced cell death only in MCL and CLL cells, which overexpressed both cannabinoid receptors, but not in BL. In vivo treatment with R(+)-MA caused a significant reduction of tumor size and mitotic index in mice xenografted with human MCL. Together, our results suggest that therapies using cannabinoid receptor ligands will have efficiency in reducing tumor burden in malignant lymphoma overexpressing CB1 and CB2.
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PMID:Expression of cannabinoid receptors type 1 and type 2 in non-Hodgkin lymphoma: growth inhibition by receptor activation. 1854 71

The initiating oncogenic event in mantle cell lymphoma (MCL) is the translocation of cyclin D1, t(11;14)(q13;q32). However, other genetic aberrations are necessary for an overt lymphoma to arise. Like other B cell lymphomas, MCL at some points during the oncogenesis is dependent on interactions with other cells and factors in the microenvironment. The G protein coupled receptors cannabinoid receptors 1 and 2 (CB1 and CB2) are expressed at low levels on non-malignant lymphocytes and at higher levels in MCL and other lymphoma subtypes. In this review we give an overview of what is known on the role of the cannabinoid receptors and their ligands in lymphoma as compared to non-malignant T and B lymphocytes. In MCL cannabinoids mainly reduce cell proliferation and induce cell death. Importantly, our recent findings demonstrate that cannabinoids may induce either apoptosis or another type of programmed cell death, cytoplasmic vacuolation/paraptosis in MCL. The signalling to death has been partly characterized. Even though cannabinoid receptors seem to be expressed in many other types of B cell lymphoma, the functional role of cannabinoid receptor targeting is yet largely unknown. In non-malignant B and T lymphocytes, cannabinoid receptors are up-regulated in response to antigen receptor signalling or CD40. For T lymphocytes IL-4 has also a crucial role in transcriptional regulation of CB1. In lymphocytes, cannabinoid act in several ways - by affecting cell migration, cytokine response, at high doses inhibit cell proliferation and inducing cell death. The possible role for the endocannabinoid system in the immune microenvironment of lymphoma is discussed.
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PMID:The role of cannabinoid receptors and the endocannabinoid system in mantle cell lymphoma and other non-Hodgkin lymphomas. 2202 69