Rewiring of cortical glucose metabolism fuels human brain cancer growth.

The brain avidly consumes glucose to fuel neurophysiology. Cancers of the brain, such as glioblastoma (GBM), lose aspects of normal biology and gain the ability to proliferate and invade healthy tissue. How brain cancers rewire glucose utilization to fuel these processes is poorly understood. Here we perform infusions of 13 C-labeled glucose into patients and mice with brain cancer to define the metabolic fates of glucose-derived carbon in tumor and cortex. By combining these measurements with quantitative metabolic flux analysis, we find that human cortex funnels glucose-derived carbons towards physiologic processes including TCA cycle oxidation and neurotransmitter synthesis. In contrast, brain cancers downregulate these physiologic processes, scavenge alternative carbon sources from the environment, and instead use glucose-derived carbons to produce molecules needed for proliferation and invasion. Targeting this metabolic rewiring in mice through dietary modulation selectively alters GBM metabolism and slows tumor growth. Significance: This study is the first to directly measure biosynthetic flux in both glioma and cortical tissue in human brain cancer patients. Brain tumors rewire glucose carbon utilization away from oxidation and neurotransmitter production towards biosynthesis to fuel growth. Blocking these metabolic adaptations with dietary interventions slows brain cancer growth with minimal effects on cortical metabolism.

Surface contamination of counting tools after mock dispensing of cyclophosphamide in a simulated outpatient pharmacy.

PURPOSE: The primary aim was to determine if dispensing of cyclophosphamide tablets resulted in accumulated residue on pharmacy counting tools during a simulated outpatient dispensing process. Secondary objectives included determining if cyclophosphamide contamination exceeded a defined threshold level of 1 ng/cm2 and if a larger number of prescriptions dispensed resulted in increased contamination. METHODS: Mock prescriptions of 40 cyclophosphamide 50 mg tablets were counted on clean trays in three scenarios using a simulated outpatient pharmacy after assaying five cleaned trays as controls. The three scenarios consisted of five simulated dispensings of one, three, or six prescriptions dispensed per scenario. Wipe samples of trays and spatulas were collected and assayed for all trays, including the five clean trays used as controls. Contamination was defined as an assayed cyclophosphamide level at or above 0.001 ng/cm2 and levels above 1 ng/cm2 were considered sufficient to cause risk of human uptake. Mean contamination for each scenario was calculated and compared using one-way analysis of variance. P-values of < 0.05 implied significance. RESULTS: Mean cyclophosphamide contamination on trays used to count one, three, and six cyclophosphamide prescriptions was 0.51 ± 0.10 (p=0.0003), 1.02 ± 0.10 (p < 0.0001), and 1.82 ± 0.10 ng/cm2 (p < 0.0001), respectively. Control trays did not show detectable cyclophosphamide contamination. Increasing the number of prescriptions dispensed from 1 to 3, 1 to 6, and 3 to 6 counts increased contamination by 0.51 ± 0.15 (p = 0.0140), 1.31 + 0.15 (p < 0.0001), and 0.80 ± 0.15 ng/cm2 (p = 0.0004), respectively. CONCLUSION: Dispensing one or more prescriptions of 40 cyclophosphamide 50 mg tablets contaminates pharmacy counting tools, and an increased number of prescriptions dispensed correlates with increased level of contamination. Counting out three or more prescriptions leads to trays having contamination that surpasses the threshold at which worker exposure may be increased. Pharmacies should consider devoting a separate tray to cyclophosphamide tablets, as cross-contamination could occur with other drugs and the efficacy of decontamination methods is unclear. Employee exposure could be minimized with the use of personal protective equipment, environmental controls, and cleaning trays between uses. Future investigation should assess the extent of drug powder dispersion, the effects of various cleaning methods, and the potential extent of contamination with different oral cytotoxic drugs.

Surface contamination of hazardous drug pharmacy storage bins and pharmacy distributor shipping containers.

Purpose This study was conducted to determine whether there is contamination on exterior drug packaging using shipping totes from the distributor and carousel storage bins as surrogate markers of external packaging contamination. Methods A two-part study was conducted to measure the presence of 5-fluorouracil, ifosfamide, cyclophosphamide, docetaxel and paclitaxel using surrogate markers for external drug packaging. In Part I, 10 drug distributor shipping totes designated for transport of hazardous drugs provided a snapshot view of contamination from regular use and transit in and out of the pharmacy. An additional two totes designated for transport of non-hazardous drugs served as controls. In Part II, old carousel storage bins (i.e. those in use pre-study) were wiped for snapshot view of hazardous drug contamination on storage bins. New carousel storage bins were then put into use for storage of the five tested drugs and used for routine storage and inventory maintenance activities. Carousel bins were wiped at time intervals 0, 8, 16 and 52 weeks to measure surface contamination. Results Two of the 10 hazardous shipping totes were contaminated. Three of the five-old carousel bins were contaminated with cyclophosphamide. One of the old carousel bins was also contaminated with ifosfamide. There were no detectable levels of hazardous drugs on any of the new storage bins at time 0, 8 or 16 weeks. However, at the Week 52, there was a detectable level of 5-FU present in the 5-FU carousel bin. Conclusions Contamination of the surrogate markers suggests that external packaging for hazardous drugs is contaminated, either during the manufacturing process or during routine chain of custody activities. These results demonstrate that occupational exposure may occur due to contamination from shipping totes and storage bins, and that handling practices including use of personal protective equipment is warranted.

Clinical developments in the treatment of relapsed or relapsed and refractory multiple myeloma: impact of panobinostat, the first-in-class histone deacetylase inhibitor.

BACKGROUND: Panobinostat is a new agent for the treatment of relapsed and refractory multiple myeloma (rrMM) as part of a combination regimen. This article presents an overview of the mechanism of action, pharmacokinetics, safety, efficacy, patient care strategies, and role of the agent in treating rrMM patients. RESULTS: Panobinostat belongs to the class of drugs known as histone deacetylase inhibitors, and has high activity against Class I, II, and IV nonhistone deacetylases and histone deacetylases. It represents the first of its class to receive approval for use in MM, and received priority review and orphan drug status in both US and Europe, when used in combination with bortezomib and dexamethasone in the treatment of rrMM. Approval of panobinostat was based on subgroup analysis of Phase III data obtained in the PANORAMA trial program for evaluation of the combination of panobinostat, bortezomib, and dexamethasone. Additional clinical trials have continued to explore optimal dosing regimens and novel combination regimens to further clarify the optimal role of panobinostat in the arsenal of drugs for rrMM. Panobinostat has shown a manageable safety profile characterized primarily by hematologic toxicities (thrombocytopenia, neutropenia, lymphopenia, and anemia), gastrointestinal toxicities, notably diarrhea and nausea, as well as fatigue/asthenia, electrolyte abnormalities, and less commonly cardiac toxicities. CONCLUSION: Panobinostat represents an important addition to the treatment armamentarium for patients with rrMM, and studies are underway evaluating its optimal dosing strategy and role in combination with other drugs used to treat this patient population.