Effective elimination of adult B-lineage acute lymphoblastic leukemia by disulfiram/copper complex in vitro and in vivo in patient-derived xenograft models

Disulfiram (DS), a clinically used drug to control alcoholism, has displayed promising anti-cancer activity against a wide range of tumors. Here, we demonstrated that DS/copper (Cu) complex effectively eliminated adult B-ALL cells in vitro and in vivo in patient-derived xenograft (PDX) humanized mouse models, reflected by inhibition of cell proliferation, induction of apoptosis, suppression of colony formation, and reduction of PDX tumor growth, while sparing normal peripheral blood mononuclear cells. Mechanistically, these events were associated with disruption of mitochondrial membrane potential and down-regulation of the anti-apoptotic proteins Bcl-2 and Bcl-xL. Further analysis on B-ALL patients’ clinical characteristics revealed that the ex vivo efficacy of DS/Cu in primary samples was significantly correlated to p16 gene deletion and peripheral blood WBC counts at diagnosis, while age, LDH level, extramedullary infiltration, status post intensive induction therapy, immune phenotype, risk category, and Ph chromosome had no effect. Together, these findings indicate that disulfiram, particularly when administrated in combination with copper, might represent a potential repurposing agent for treatment of adult B-ALL patients, including those clinically characterized by one or more adverse prognostic factors

Probabilistic exposure assessment model to estimate aseptic-UHT product failure rate

Aseptic-Ultra-High-Temperature (UHT) products are manufactured to be free of microorganisms capable of growing in the food at normal non-refrigerated conditions at which the food is likely to be held during manufacture, distribution and storage. Two important phases within the process are widely recognised as critical in controlling microbial contamination: the sterilisation steps and the following aseptic steps. Of the microbial hazards, the pathogen spore formers Clostridium botulinum and Bacillus cereus are deemed the most pertinent to be controlled. In addition, due to a relatively high thermal resistance, Geobacillus stearothermophilus spores are considered a concern for spoilage of low acid aseptic-UHT products. A probabilistic exposure assessment model has been developed in order to assess the aseptic-UHT product failure rate associated with these three bacteria. It was a Modular Process Risk Model, based on nine modules. They described: i) the microbial contamination introduced by the raw materials, either from the product (i.e. milk, cocoa and dextrose powders and water) or the packaging (i.e. bottle and sealing component), ii) the sterilisation processes, of either the product or the packaging material, iii) the possible recontamination during subsequent processing of both product and packaging. The Sterility Failure Rate (SFR) was defined as the sum of bottles contaminated for each batch, divided by the total number of bottles produced per process line run (10(6) batches simulated per process line). The SFR associated with the three bacteria was estimated at the last step of the process (i.e. after Module 9) but also after each module, allowing for the identification of modules, and responsible contamination pathways, with higher or lower intermediate SFR. The model contained 42 controlled settings associated with factory environment, process line or product formulation, and more than 55 probabilistic inputs corresponding to inputs with variability conditional to a mean uncertainty. It was developed in @Risk and run through Monte Carlo simulations. Overall, the highest SFR was associated with G. stearothermophilus (380000 bottles contaminated in 10(11) bottles produced) and the lowest to C. botulinum (3 bottles contaminated in 10(11) bottles produced). Unsurprisingly, SFR due to G. stearothermophilus was due to its ability to survive the UHT treatment. More interestingly, it was identified that SFR due to B. cereus (17000 bottles contaminated in 10(11) bottles produced) was due to an airborne recontamination of the aseptic tank (49%) and a post-sterilisation packaging contamination (33%). A deeper analysis (sensitivity and scenario analyses) was done to investigate how the SFR due to B. cereus could be reduced by changing the process settings related to potential air recontamination source