Experiments were performed in accordance with the Office of Laboratory Animal Welfare and approved by the Institutional Animal Care and Use Committee at the Massachusetts General Hospital. BET bromodomain inhibitor CPI203 (BETi) (10 mg/kg) or vehicle control were administered by intraperitoneal injection to 6–7 week old B6:129 mice (Jackson Laboratory, Bar Harbor, Maine) twice daily for 1, 5, 7, or 14 days. I-BET151 (30 mg/kg) was similarly administered once a day for 14 days. Gemcitabine (40 mg/kg) was administered to mice twice a week by intraperitoneal injection. Proliferating cells were labeled with bromodeoxyuridine (BrdU) (100 mg/kg) given by intraperitoneal injection 2 hours prior to euthanasia.
For in vivo intestinal permeability, mice were food fasted for 6 hours prior to gastric gavage administration of phosphate buffer saline (PBS, pH 7.2) containing fluorescein isothiocyanate (FITC)-dextran (4 kDa) (Sigma, Saint Lois, MO) at a dose of 300 mg/kg body weight. Three hours after gavage, blood was collected by cardiac puncture and the serum was used to assess the level of FITC-dextran as an indicator of intestinal permeability as previously described37 (link).
For in vivo intestinal permeability, mice were food fasted for 6 hours prior to gastric gavage administration of phosphate buffer saline (PBS, pH 7.2) containing fluorescein isothiocyanate (FITC)-dextran (4 kDa) (Sigma, Saint Lois, MO) at a dose of 300 mg/kg body weight. Three hours after gavage, blood was collected by cardiac puncture and the serum was used to assess the level of FITC-dextran as an indicator of intestinal permeability as previously described37 (link).