Cannabinoid receptor 1 (CB1R) and cannabinoid receptor 2 (CB2R) are G protein-coupled receptors (GPCRs) that activate a variety of pathways upon activation by (partial) agonists including the G... Show moreCannabinoid receptor 1 (CB1R) and cannabinoid receptor 2 (CB2R) are G protein-coupled receptors (GPCRs) that activate a variety of pathways upon activation by (partial) agonists including the G protein pathway and the recruitment of β-arrestins. Differences in the activation level of these pathways lead to biased signaling. Here, we describe a detailed protocol to characterize the potency and efficacy of ligands to induce or inhibit β-arrestin recruitment to the human CB1R and CB2R using the PathHunter® assay. This is a cellular assay that uses a β-galactosidase complementation system which has a chemiluminescent read-out and can be performed in 384-well plates. We have successfully used this assay to characterize a set of reference ligands (both agonists, antagonists, and an inverse agonist) on human CB1R and CB2R, of which some examples will be presented here. Show less
Qiao, X.H.; Zanden, S.Y. van der; Wander, D.P.A.; Borras, D.M.; Song, J.Y.; Li, X.Y.; ... ; Neefjes, J. 2020
The anthracycline doxorubicin (Doxo) and its analogs daunorubicin (Daun), epirubicin (Epi), and idarubicin (Ida) have been cornerstones of anticancer therapy for nearly five decades. However, their... Show moreThe anthracycline doxorubicin (Doxo) and its analogs daunorubicin (Daun), epirubicin (Epi), and idarubicin (Ida) have been cornerstones of anticancer therapy for nearly five decades. However, their clinical application is limited by severe side effects, especially dose-dependent irreversible cardiotoxicity. Other detrimental side effects of anthracyclines include therapy-related malignancies and infertility. It is unclear whether these side effects are coupled to the chemotherapeutic efficacy. Doxo, Daun, Epi, and Ida execute two cellular activities: DNA damage, causing double-strand breaks (DSBs) following poisoning of topoisomerase II (Topo II), and chromatin damage, mediated through histone eviction at selected sites in the genome. Here we report that anthracycline-induced cardiotoxicity requires the combination of both cellular activities. Topo II poisons with either one of the activities fail to induce cardiotoxicity in mice and human cardiac microtissues, as observed for aclarubicin (Acla) and etoposide (Etop). Further, we show that Doxo can be detoxified by chemically separating these two activities. Anthracycline variants that induce chromatin damage without causing DSBs maintain similar anticancer potency in cell lines, mice, and human acute myeloid leukemia patients, implying that chromatin damage constitutes a major cytotoxic mechanismof anthracyclines. With these anthracyclines abstained from cardiotoxicity and therapy-related tumors, we thus uncoupled the side effects from anticancer efficacy. These results suggest that anthracycline variants acting primarily via chromatin damage may allow prolonged treatment of cancer patients and will improve the quality of life of cancer survivors. Show less
The anthracycline doxorubicin (Doxo) and its analogs daunorubicin (Daun), epirubicin (Epi), and idarubicin (Ida) have been cornerstones of anticancer therapy for nearly five decades. However, their... Show moreThe anthracycline doxorubicin (Doxo) and its analogs daunorubicin (Daun), epirubicin (Epi), and idarubicin (Ida) have been cornerstones of anticancer therapy for nearly five decades. However, their clinical application is limited by severe side effects, especially dose-dependent irreversible cardiotoxicity. Other detrimental side effects of anthracyclines include therapy-related malignancies and infertility. It is unclear whether these side effects are coupled to the chemotherapeutic efficacy. Doxo, Daun, Epi, and Ida execute two cellular activities: DNA damage, causing double-strand breaks (DSBs) following poisoning of topoisomerase II (Topo II), and chromatin damage, mediated through histone eviction at selected sites in the genome. Here we report that anthracycline-induced cardiotoxicity requires the combination of both cellular activities. Topo II poisons with either one of the activities fail to induce cardiotoxicity in mice and human cardiac microtissues, as observed for aclarubicin (Acla) and etoposide (Etop). Further, we show that Doxo can be detoxified by chemically separating these two activities. Anthracycline variants that induce chromatin damage without causing DSBs maintain similar anticancer potency in cell lines, mice, and human acute myeloid leukemia patients, implying that chromatin damage constitutes a major cytotoxic mechanism of anthracyclines. With these anthracyclines abstained from cardiotoxicity and therapy-related tumors, we thus uncoupled the side effects from anticancer efficacy. These results suggest that anthracycline variants acting primarily via chromatin damage may allow prolonged treatment of cancer patients and will improve the quality of life of cancer survivors. Show less
IMPORTANCE For patients with painful chronic pancreatitis, surgical treatment is postponed until medical and endoscopic treatment have failed. Observational studies have suggested that earlier... Show moreIMPORTANCE For patients with painful chronic pancreatitis, surgical treatment is postponed until medical and endoscopic treatment have failed. Observational studies have suggested that earlier surgery could mitigate disease progression, providing better pain control and preserving pancreatic function.OBJECTIVE To determine whether early surgery is more effective than the endoscopy-first approach in terms of clinical outcomes.DESIGN, SETTING, AND PARTICIPANTS The ESCAPE trial was an unblinded, multicenter, randomized clinical superiority trial involving 30 Dutch hospitals participating in the Dutch Pancreatitis Study Group. From April 2011 until September 2016, a total of 88 patients with chronic pancreatitis, a dilated main pancreatic duct, and who only recently started using prescribed opioids for severe pain (strong opioids for <= 2 months or weak opioids for <= 6 months) were included. The 18-month follow-up period ended in March 2018.INTERVENTIONS There were 44 patients randomized to the early surgery group who underwent pancreatic drainage surgery within 6 weeks after randomization and 44 patients randomized to the endoscopy-first approach group who underwent medical treatment, endoscopy including lithotripsy if needed, and surgery if needed.MAIN OUTCOMES AND MEASURES The primary outcome was pain, measured on the Izbicki pain score and integrated over 18 months (range, 0-100 [increasing score indicates more pain severity]). Secondary outcomes were pain relief at the end of follow-up; number of interventions, complications, hospital admissions; pancreatic function; quality of life (measured on the 36-Item Short Form Health Survey [SF-36]); and mortality.RESULTS Among 88 patients who were randomized (mean age, 52 years; 21 (24%) women), 85 (97%) completed the trial. During 18 months of follow-up, patients in the early surgery group had a lower Izbicki pain score than patients in the group randomized to receive the endoscopy-first approach group (37 vs 49; between-group difference, -12 points [95% CI, -22 to -2]; P = .02). Complete or partial pain relief at end of follow-up was achieved in 23 of 40 patients (58%) in the early surgery vs 16 of 41 (39%)in the endoscopy-first approach group (P = .10). The total number of interventions was lower in the early surgery group (median, 1 vs 3; P < .001). Treatment complications (27% vs 25%), mortality (0% vs 0%), hospital admissions, pancreatic function, and quality of life were not significantly different between early surgery and the endoscopy-first approach.CONCLUSIONS AND RELEVANCE Among patients with chronic pancreatitis, early surgery compared with an endoscopy-first approach resulted in lower pain scores when integrated over 18 months. However, further research is needed to assess persistence of differences over time and to replicate the study findings. Show less
Soethoudt, M.; Grether, U.; Fingerle, J.; Grim, T.W.; Fezza, F.; Petrocellis, L. de; ... ; Stelt, M. van der 2017