Painful cutaneous ulcers are a clinical challenge as the pain can be difficult to control, frequently requiring a combination of pharmacological and non-pharmacological measures. There is evidence suggesting topical opioid application might be efficacious in the management of painful cutaneous ulcers, however this is largely based on case reports. Methods A series of clinical and laboratory studies were undertaken to determine the utility of opioids applied topically to painful cutaneous ulcers, these included surveys of hospice admissions to determine the prevalence of painful ulcers and the effective dose of topical opioid; a randomised, double-blind, placebo-controlled crossover trial design to assess the utility of morphine/IntraSite gel mixture, HPLC analysis to determine the mixture’s bioavailability and physical stability, and microbiological studies to determine its microbiological stability. Results A survey of 323 hospice admissions over a two-year period identified 125 patients with 221 ulcers, mostly caused by either pressure (183 ulcers) or trauma (25); 147 (67%) of all ulcers were painful. Compared to placebo, morphine/IntraSite mixture was more efficacious; it was safe and well tolerated in this population. Morphine applied topically appears to have an analgesic effect even at low doses of morphine irrespective of background analgesic medication. HPLC analyses suggested morphine and its metabolites might be detectable in the plasma of patients with large ulcers, but only at low concentrations. In addition morphine/IntraSite gel mixture was physically and, under certain storage conditions, microbiologically stable for 28 days allowing the mixture to be prepared and stored before use. Conclusions The studies confirmed that painful cutaneous ulcers are a significant clinical problem in hospice patients and that morphine/IntraSite mixture can be used safely and effectively in this patient group. Bioavailability studies support the possibility that the opioid analgesic effect is local rather than systemic, and stability studies show the morphine/IntraSite combination, once mixed, can be stored for up to 28 days, allowing the mixture to be prepared and stored before use. Given that ulcers can vary in aetiology, size, severity and temporal characteristics of pain, an individualised titration protocol is recommended. Further research is required to confirm and extend these findings to other ulcers and clinical settings.

Yes / Non-invasive methods to monitor tumour growth are an important goal in cancer drug development. Thermographic imaging systems offer potential in this area, since a change in temperature is known to be induced due to changes within the tumour microenvironment. This study demonstrates that this imaging modality can be applied to a broad range of tumour xenografts and also, for the first time, the methodology’s suitability to assess anti-cancer agent efficacy. Mice bearing subcutaneously implanted H460 lung cancer xenografts were treated with a novel vascular disrupting agent, ICT-2552, and the cytotoxin doxorubicin. The effects on tumour temperature were assessed using thermographic imaging over the first 6 hours post-administration and subsequently a further 7 days. For ICT-2552 a significant initial temperature drop was observed, whilst for both agents a significant temperature drop was seen compared to controls over the longer time period. Thus thermographic imaging can detect functional differences (manifesting as temperature reductions) in the tumour response to these anti-cancer agents compared to controls. Importantly, these effects can be detected in the first few hours following treatment and therefore the tumour is observable non-invasively. As discussed, this technique will have considerable 3Rs benefits in terms of reduction and refinement of animal use. / University of Bradford

Inadequate metabolic conditions in solid tumors lead to the formation of quiescent cancer cells that are suspended in a transient cell cycle arrest. When conditions change, quiescent cancer cells can re-enter the cell cycle and cause recurrence. Drug screening efforts have revealed mitochondrial oxidative phosphorylation as a unique metabolic dependency in quiescent cancer cells. The anthelmintic drug nitazoxanide is an inhibitor of oxidative phosphorylation and preferentially active against quiescent cancer cells in multicellular tumor spheroids.  In this thesis, we employed current and developed new models of quiescent cancer cells and applied live cell imaging for improved preclinical evaluation of cancer drugs in hepatocellular and colorectal carcinoma cell lines. As part of this work, a new assay to measure mitochondrial membrane potential in three-dimensional cell models was developed, an application of the JC-1 assay, and we demonstrated that the preferential activity against quiescent cancer cells of nitazoxanide is shared by two kinase inhibitors: sorafenib and regorafenib. The sensitivity of quiescent cancer cells to nitazoxanide, sorafenib, and regorafenib correlated with the disruption of the mitochondrial membrane potential. Nitazoxanide and sorafenib, in combination, caused an additive decrease in viability, mitochondrial membrane potential, and colony regrowth capacity.  Furthermore, we developed a quiescent hollow fiber assay and implemented an improved analysis using live cell imaging and adenosine triphosphate analysis. Hypoxia and cancer cell quiescence were enriched in hollow fiber macrocapsules over time, and the culture conditions affected nitazoxanide sensitivity. Additionally, we used basement membrane extract gel to support cell growth in hollow fiber macrocapsules and implanted macrocapsules in mice. We observed that the in vivo environment was favorable to cell growth. Through this characterization of the quiescent hollow fiber assay, we were able to outline important paths for future research.