Angiogenesis is an early event in the development of chemically induced skin tumors

In this study we have analyzed the vascular response induced in the two- stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not been explored in this model, which is the paradigm of multistage carcinogenesis and a model for neoplastic lesions derived from exophytic premalignant lesions (e.g. colon carcinoma, bladder papilloma). We investigated if angiogenesis is involved in the formation of papillomas and in the progression from papilloma to carcinoma. To this end we analyzed the vasculature of normal and hyperplastic skin, focal epidermal hyperplasias that are precursors of papillomas, papillomas at different stages and squamous cell carcinomas. We also analyzed the vascularization of papillomas induced in two strains of mice that differ in their susceptibility to malignant progression. We show here that angiogenesis is turned on in the earliest stages of papilloma formation. In late stages, regardless of state of progression, the predominant response is an increase in the size of blood vessels. Thus, in the SENCAR mouse model, representative of exophytic tumors, the angiogenesis switch is a very early event, probably mechanistically related to the development of the primarily exophytic lesions. Therefore, the density of blood vessels cannot be used as a predictor of malignant progression in this model.      

A novel system for simultaneous monitoring of locomotor and sound activities in animals

This paper describes a PC-based system for simultaneous monitoring of locomotor and sound activities on small rodents. The displacement and location signals of the animal were first determined across consecutive video-frames, followed by marked data reduction to cater for long-term studies. At the same time, sounds generated by the animal were detected and the sound level was recorded as root-mean-square values at 1 s intervals. Preliminary data showed that such a multi-parametric monitor system could provide comprehensive information on the animal's activity.     

Individualized prophylaxis for optimizing hemophilia care: can we apply this to both developed and developing nations?

Prophylaxis is considered optimal care for hemophilia patients to prevent bleeding and to preserve joint function thereby improving quality of life (QoL). The evidence for prophylaxis is irrefutable and is the standard of care in developed nations. Prophylaxis can be further individualized to improve outcomes and cost effectiveness. Individualization is best accomplished taking into account the bleeding phenotype, physical activity/lifestyle, joint status, and pharmacokinetic handling of specific clotting factor concentrates, all of which vary among individuals. Patient acceptance should also be considered. Assessment tools (e.g. joint status imaging and function studies/scores, QoL) for determining and monitoring risk factors and outcome, as well as population PK profiling have been developed to assist the individualization process. The determinants of optimal prophylaxis include (1) factor dose/dosing frequency, hence, cost/affordability (2) bleeding triggers (physical activity/lifestyle, chronic arthropathy and synovitis) and (3) bleeding rates. Altering one determinant results in adjustment of the other two. Thus, the trough level to protect from spontaneous bleeding can be increased in patients who have greater bleeding risks; and prophylaxis to achieve zero joint bleeds is achievable through optimal individualization. Prophylaxis in economically constrained nations is limited by the ill-affordability of clotting factor concentrates. However, at least 5 studies on children and adults from Thailand, China and India have shown superiority of low dose (~5–10 IU kg^?1 2-3× per week) prophylaxis over episodic treatment in terms of bleed reduction, and quality of life, with improved physical activity, independent functioning, school attendance and community participation. In these nations, the prophylaxis goals should be for improved QoL rather than “zero bleeds” and perfect joints. Prophylaxis can still be individualized to affordability. Higher protective trough level can be achieved by using smaller doses given more frequently without an increase in consumption/cost. The bleeding trigger can also be down-regulated by avoiding unnecessary injury, and by engaging in judicious strengthening exercises appropriate to the joint status to improve balance and joint stabilization. Central to the success of prophylaxis are clinics with comprehensive care that provide the necessary professional expertise, support, and counseling, to educate patients, families, and other healthcare professionals, and to support research for improved hemophilia care.     

Global gene expression in pseudomyxoma peritonei,with parallel development of two immortalized cell lines

Pseudomyxoma peritonei (PMP) is a rare tumor of appendiceal origin. Treatment is major cytoreductive surgery but morbidity is high. PMP is considered chemo-resistant; its molecular biology is understudied; and presently, there is no platform for pre-clinical drug testing. Here, we performed exon array analysis from laser micro-dissected PMP tissue and normal colonic epithelia. The array analysis identified 27 up-regulated and 34 down-regulated genes: candidate up-regulated genes included SLC16A4, DSC3, Aldolase B, EPHX4, and ARHGAP24; candidate down-regulated genes were MS4A12, TMIGD1 and Caspase-5. We confirmed differential expression of the candidate genes and their protein products using in-situ hybridization and immuno-histochemistry. In parallel, we established two primary PMP cell lines, N14A and N15A, and immortalized with an SV40 T-antigen lentiviral vector. We cross-checked for expression of the candidate genes (from the array analyses) using qPCR in the cell lines and demonstrated that the gene profiles were distinct from those of colorectal tumor libraries and commonly used colon cell lines. N14A and N15A were responsiveness to mitomycin and oxaliplatin. This study characterizes global gene expression in PMP, and the parallel development of the first immortalized PMP cell lines; fit for pre-clinical testing and PMP oncogene discovery.     

Guidelines and considerations for conducting experiments using tissue microarrays

Tissue microarrays (TMAs) represent a powerful method for undertaking large‐scale tissue‐based biomarker studies. While TMAs offer several advantages, there are a number of issues specific to their use which need to be considered when employing this method. Given the investment in TMA‐based research, guidance on design and execution of experiments will be of benefit and should help researchers new to TMA‐based studies to avoid known pitfalls. Furthermore, a consensus on quality standards for TMA‐based experiments should improve the robustness and reproducibility of studies, thereby increasing the likelihood of identifying clinically useful biomarkers. In order to address these issues, the National Cancer Research Institute Biomarker and Imaging Clinical Studies Group organized a 1‐day TMA workshop held in Nottingham in May 2012. The document herein summarizes the conclusions from the workshop. It includes guidance and considerations on all aspects of TMA‐based research, including the pre‐analytical stages of experimental design, the analytical stages of data acquisition, and the postanalytical stages of data analysis. A checklist is presented which can be used both for planning a TMA experiment and interpreting the results of such an experiment. For studies of cancer biomarkers, this checklist could be used as a supplement to the REMARK guidelines.