An eGFP expressing immunodeficent mouse model with dsRED transfected mammary tumours, and the effect of hyperbaric oxygen treatment

Previous studies have shown significant anti-tumour effects of hyperbaric oxygen (HBO) treatment on chemically induced mammary tumours. Thus, to answer whether HBO has a general anti-tumour effect on mammary tumours, the study had three aims: 1. Establish two new mammary tumour models using eGFP (Green Fluorescent Protein) expressing immunodeficient mice and dsRed transfected tumour cells (4T1 and MCF7). 2. Elucidate possible effects of HBO treatment on tumour growth and angiogenesis. 3. Analyze the effect of HBO on the tumour interstitium. Methods: DsRed transfected cells were injected s.c. into the immunodeficient eGFP mice in the groin-area. All mice received oestrogen treatment prior to injection. After tumour development (~3mm) the mice were divided into three groups. One group was exposed to repeated HBO treatments (3 exposures), one to a single HBO treatment (both to 2.5 bar, 100% O2, à 90min) and controls to normal atmosphere (1 bar, 21% O2). Light microscopy, as well as multiphoton confocal microscopy, enabled investigation of the tumour-host interaction in situ. Treatment effects were determined by assessment of tumour growth (with calliper) and angiogenesis (CD31 staining). Moreover, tumour stromal factors such as Pif (with the wick-in-needle technique), collagen content (by hydroxyproline quantification) together with drug uptake ([3H]-5FU, using microdialysis) were measured. Results: Three million 4T1 dsRed cells injected in the eGFP mice induced tumours. The tumour cells invaded the stromal cells and a number of vascular elements were found in situ. Five million MCF7 cells injected in conjunction with matrigel did also induce tumours, although this model has to be further elucidated. In the 4T1 mammary model, tumour growth and angiogenesis were significantly reduced after repeated HBO treatment compared to control. However, no change in collagen density was found. A significant reduction in Pif was found in both HBO treated groups. Nevertheless, this did not affect the drug uptake. Conclusion: We have successfully established a dsRed transfected 4T1 mammary tumour in eGFP expressing mice. We also developed MCF7 human mammary tumours, although this model needs further refinement. The reduction in 4T1 tumour growth found after HBO treatment can, to some extent, be explained by the reduction in angiogenesis. The collagen density was unchanged after HBO treatment, possibly due to the short treatment period. A reduction in Pif was found after HBO treatment, thus without inducing enhanced drug uptake. The mechanisms behind these effects need to be further elucidated

Implementation of enhanced cognitive behaviour therapy (CBT-E) for adults with anorexia nervosa in an outpatient eating-disorder unit at a public hospital

Background Anorexia nervosa (AN) in adults is difficult to treat, and no current treatment is supported by robust evidence. A few studies, most of which were performed by highly specialized research units, have indicated that enhanced cognitive behaviour therapy (CBT-E) for eating disorders can be effective. However, the dropout rate is high and the evidence from non-research clinical units is sparse. Methods This quality assessment project implemented CBT-E in an outpatient setting at a public hospital. Forty-four patients with AN started therapy. Each patient received at least 40 sessions of CBT-E over a 12-month period. Their body mass index (BMI) was recorded at baseline and after 3, 6 and 12 months. Reasons for not starting therapy or for leaving therapy prematurely were recorded. Results Half (n = 22) of the 44 patients who started outpatient CBT-E did not complete the treatment. In the remaining sample there was a large (and statistically significant) weight gain after 12 months. The percentage of patients achieving the target BMI of > 18.5 kg/m2 was 36.4, 50.0 and 77.3% after 3, 6 and 12 months, respectively. Conclusions This quality assessment project shows that it is possible to establish effective CBT-E in an outpatient eating-disorder unit at a public hospital. Although half of the patients did not complete CBT-E, the remaining patients achieved a significant increase in BMI at 1 year after the start of therapy

Gene expression in tumor cells and stroma in dsRed 4T1 tumors in eGFP-expressing mice with and without enhanced oxygenation

Background The tumor microenvironment is pivotal in tumor progression. Thus, we aimed to develop a mammary tumor model to elucidate molecular characteristics in the stroma versus the tumor cell compartment by global gene expression. Secondly, since tumor hypoxia influences several aspects of tumor pathophysiology, we hypothesized that hyperoxia might have an inhibitory effect on tumor growth per se. Finally, we aimed to identify differences in gene expression and key molecular mechanisms, both in the native state and following treatment. Methods 4T1 dsRed breast cancer cells were injected into eGFP expressing NOD/SCID mice. Group 1 was exposed to 3 intermittent HBO treatments (Day 1, 4 and 7), Group 2 to 7 daily HBO treatments (both 2.5bar, 100% O2, à 90 min), whereas the controls were exposed to a normal atmosphere. Tumor growth, histology, vascularisation, cell proliferation, cell death and metastasis were assessed. Fluorescence-activated cell sorting was used to separate tumor cells from stromal cells prior to gene expression analysis. Results The purity of sorted cells was verified by fluorescence microscopy. Gene expression profiling demonstrated that highly expressed genes in the untreated tumor stroma included constituents of the extracellular matrix and matrix metalloproteinases. Tumor growth was significantly inhibited by HBO, and the MAPK pathway was found to be significantly reduced. Immunohistochemistry indicated a significantly reduced microvessel density after intermittent HBO, whereas daily HBO did not show a similar effect. The anti-angiogenic response was reflected in the expression trends of angiogenic factors. Conclusions The present in vivo mammary tumor model enabled us to separate tumor and stromal cells, and demonstrated that the two compartments are characterized by distinct gene expressions, both in the native state and following HBO treatments. Furthermore, hyperoxia induced a significant tumor growth-inhibitory effect, with significant down-regulation of the MAPK pathway. An anti-angiogenic effect after intermittent HBO was observed, and reflected in the gene expression profile

Gene expression in tumor cells and stroma in dsRed 4T1 tumors in eGFP-expressing mice with and without enhanced oxygenation

Abstract Background The tumor microenvironment is pivotal in tumor progression. Thus, we aimed to develop a mammary tumor model to elucidate molecular characteristics in the stroma versus the tumor cell compartment by global gene expression. Secondly, since tumor hypoxia influences several aspects of tumor pathophysiology, we hypothesized that hyperoxia might have an inhibitory effect on tumor growth per se. Finally, we aimed to identify differences in gene expression and key molecular mechanisms, both in the native state and following treatment. Methods 4T1 dsRed breast cancer cells were injected into eGFP expressing NOD/SCID mice. Group 1 was exposed to 3 intermittent HBO treatments (Day 1, 4 and 7), Group 2 to 7 daily HBO treatments (both 2.5bar, 100% O2, à 90 min), whereas the controls were exposed to a normal atmosphere. Tumor growth, histology, vascularisation, cell proliferation, cell death and metastasis were assessed. Fluorescence-activated cell sorting was used to separate tumor cells from stromal cells prior to gene expression analysis. Results The purity of sorted cells was verified by fluorescence microscopy. Gene expression profiling demonstrated that highly expressed genes in the untreated tumor stroma included constituents of the extracellular matrix and matrix metalloproteinases. Tumor growth was significantly inhibited by HBO, and the MAPK pathway was found to be significantly reduced. Immunohistochemistry indicated a significantly reduced microvessel density after intermittent HBO, whereas daily HBO did not show a similar effect. The anti-angiogenic response was reflected in the expression trends of angiogenic factors. Conclusions The present in vivo mammary tumor model enabled us to separate tumor and stromal cells, and demonstrated that the two compartments are characterized by distinct gene expressions, both in the native state and following HBO treatments. Furthermore, hyperoxia induced a significant tumor growth-inhibitory effect, with significant down-regulation of the MAPK pathway. An anti-angiogenic effect after intermittent HBO was observed, and reflected in the gene expression profile.</p