Modulation of fatty acid metabolism and immune suppression are features of in vitro tumour sphere formation in ontogenetically distinct dog cancers.

Non-adherent, 3-dimensional sphere formation is used as an in vitro surrogate to evaluate cellular potential for tumour initiation and self-renewal. To determine if a shared molecular program underlies the capacity for sphere formation by cells originating from diverse tumour types, we characterized molecular and functional properties of 10 independent cell lines derived from 3 ontogenetically distinct dog cancers: hemangiosarcoma, osteosarcoma and glial brain tumours. Genome-wide gene expression profiling identified tumour-of-origin-dependent patterns of adjustment to sphere formation in a uniform culture condition. However, expression of the stem/progenitor markers CD34 and CD117, resistance to cytotoxic drugs and dye efflux (side population assays) showed no association with these gene expression profiles. Instead, primary sphere-forming capacity was inversely correlated with the ability to reform secondary spheres, regardless of tumour ontogeny. Primary sphere formation seemed to be proportional to the number of pre-existing cells with sphere-forming capacity in the cell lines. Cell lines where secondary sphere formation was more proficient than primary sphere formation showed enrichment of genes involved in fatty acid synthesis and immunosuppressive cytokines. In contrast, cell lines where secondary sphere formation was approximately equivalent to or less proficient than primary sphere formation showed upregulation of CD40 and enrichment of genes involved in fatty acid oxidation. Our data suggest that in vitro sphere formation is associated with upregulation of gene clusters involved in metabolic and immunosuppressive functions, which might be necessary for self-renewal and for tumour initiation and/or tumour propagation in vivo.

Fatty acid synthase as a potential therapeutic target in feline oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) is an aggressive and treatment-resistant malignancy in both feline and human patients. Recent work has demonstrated aberrant expression of fatty acid synthase (FASN) and an increased capacity for lipogenesis in human OSCC and other cancers. In human OSCC, inhibition of FASN decreased cell viability and growth in vitro, and diminished tumour growth and metastasis in murine preclinical models. This study aimed to characterize FASN as a therapeutic target in feline OSCC. Immunohistochemistry revealed high FASN expression in primary feline OSCC tumours, and FASN expression was detected in OSCC cell lines (3 feline and 3 human) by immunoblotting and quantitative real-time-polymerase chain reaction (qRT-PCR). Orlistat, a FASN inhibitor, substantially reduced cell viability in both feline and human OSCC lines, although feline cell lines consistently displayed higher sensitivity to the drug. FASN mRNA expression among cell lines mirrored sensitivity to orlistat, with feline cell lines expressing higher levels of FASN. Consistent with this observation, diminished sensitivity to orlistat treatment and decreased FASN mRNA expression were observed in feline OSCC cells following incubation under hypoxic conditions. Treatment with orlistat did not potentiate sensitivity to carboplatin in the cell lines investigated; instead, combinations of the 2 drugs resulted in additive to antagonistic effects. Our results suggest that FASN inhibition is a viable therapeutic target for feline OSCC. Furthermore, cats may serve as a spontaneous large animal model for human oral cancer, although differences in the regulation of lipogenesis between these 2 species require further investigation.

Yield of Image-Guided Needle Biopsy for Infectious Discitis: A Systematic Review and Meta-Analysis.

BACKGROUND: Image-guided biopsy is routinely conducted in patients with suspected discitis, though the sensitivity reported in the literature ranges widely. PURPOSE: We applied a systematic review and meta-analysis to estimate the yield of image-guided biopsy for infectious discitis. DATA SOURCES: We performed a literature search of 4 data bases: PubMed, Cochrane CENTRAL Register of Controlled Trials, Embase.com, and Scopus from data base inception to March 2016. STUDY SELECTION: A screen of 1814 articles identified 88 potentially relevant articles. Data were extracted for 33 articles, which were eligible if they were peer-reviewed publications of patients with clinical suspicion of discitis who underwent image-guided biopsy. DATA ANALYSIS: Patients with positive cultures out of total image-guided biopsy procedures were pooled to estimate yield with 95% confidence intervals. Hypothesis testing was performed with an inverse variance method after logit transformation. DATA SYNTHESIS: Image-guided biopsy has a yield of approximately 48% (793/1763), which is significantly lower than the open surgical biopsy yield of 76% (152/201; P < .01). Biopsy in patients with prior antibiotic exposure had a yield of 32% (106/346), which was not significantly different from the yield of 43% (336/813; P = .08) in patients without prior antibiotic exposure. LIMITATIONS: The conclusions of this meta-analysis are primarily limited by the heterogeneity of the included studies. CONCLUSIONS: Image-guided biopsy has a moderate yield for the diagnosis of infectious discitis, which is significantly lower than the yield of open surgical biopsy. This yield is not significantly affected by prior antibiotic use.

Identification of drug-resistant subpopulations in canine hemangiosarcoma.

Canine hemangiosarcoma is a rapidly progressive disease that is poorly responsive to conventional chemotherapy. Despite numerous attempts to advance treatment options and improve outcomes, drug resistance remains a hurdle to successful therapy. To address this problem, we used recently characterized progenitor cell populations derived from canine hemangiosarcoma cell lines and grown as non-adherent spheres to identify potential drug resistance mechanisms as well as drug-resistant cell populations. Cells from sphere-forming cultures displayed enhanced resistance to chemotherapy drugs, expansion of dye-excluding side populations and altered ATP-binding cassette (ABC) transporter expression. Invasion studies demonstrated variability between cell lines as well as between sphere and monolayer cell populations. Collectively, our results suggest that sphere cell populations contain distinct subpopulations of drug-resistant cells that utilize multiple mechanisms to evade cytotoxic drugs. Our approach represents a new tool for the study of drug resistance in hemangiosarcoma, which could alter approaches for treating this disease.

Endocrine disruptor & nutritional effects of heavy metals in ovarian hyperstimulation.

PURPOSE: There is increasing concern that environmental chemicals have a direct effect on fertility. Heavy metals such as mercury have been shown to affect various organ systems in humans including nervous system and skin, however they could also act as endocrine disrupting chemicals adversely affecting fertility. Metals such as zinc and selenium are essential micronutrients with diverse functions that may be important for reproductive outcomes. We measured mercury, zinc and selenium levels in the hair, a reliable reflection of long term environmental exposure and dietary status, to correlate with the outcome of ovarian hyperstimulation for in vitro fertilisation (IVF) treatment. METHODS: We analysed the hair of 30 subfertile women for mercury, zinc and selenium using inductively coupled mass spectrometry. Each woman underwent one cycle of IVF treatment. Correlation between the levels of these trace metals and treatment outcomes was investigated. RESULTS: Thirty women were recruited with mean (±SD) age of 32.7(4.4) years and BMI of 25.4(5.0)kg/m(2). Hair mercury concentration showed a negative correlation with oocyte yield (p < 0.05,ßcoefficient 0.38) and follicle number (p = 0.03,ß coefficient0.19) after ovarian stimulation. Zinc and selenium levels in hair correlated positively with oocyte yield after ovarian stimulation (p < 0.05,ß coefficient0.15) and (p = 0.03,ß coefficient0.21) respectively. Selenium levels in hair correlated significantly with follicle number following stimulation (p = 0.04, ßcoefficient0.22). There was no correlation between mercury, zinc and selenium in hair and their corresponding serum levels. CONCLUSION: These data suggest that mercury had a deleterious effect whilst there was a positive effect for zinc and selenium in the ovarian response to gonadotrophin therapy for IVF. Hair analysis offers a novel method of investigating the impact of long-term exposure to endocrine disruptors and nutritional status on reproductive outcomes.

Insulin resistance and free androgen index correlate with the outcome of controlled ovarian hyperstimulation in non-PCOS women undergoing IVF.

BACKGROUND: The dual effects of insulin and androgen on the ovary act to promote early folliculogenesis. In the context of polycystic ovarian syndrome (PCOS), the presence of hyperinsulinaemia, resulting from increased insulin resistance (IR), and hyperandrogenaemia lead to the appearance of multiple antral follicles and frequently a multi-follicular response to gonadotrophin stimulation for assisted reproductive treatments (ARTs). The effect of IR and androgen status in women without PCOS on the follicular outcome of controlled ovarian hyperstimulation (COH) is not known. METHODS: We assessed the IR [using the homeostasis model assessment (HOMA)] and androgen status of 49 women without PCOS undergoing an ART cycle. This was then related to the treatment cycle outcome. RESULTS: We found a significant positive correlation between HOMA and BMI, and free androgen index (FAI) and testosterone. The FAI significantly positively correlated with total follicle count after COH. The total follicle count was significantly higher in those with a HOMA >2.5, and HOMA positively correlated with total follicle count in this group of IR women (HOMA > 2.5). CONCLUSIONS: Our results suggest a positive correlation of HOMA-IR levels above a threshold level of 2.5 and a continuous positive correlation of free androgen (FAI) to total ovarian follicle count following COH in the non-PCOS patient.

Fluvastatin reduces oxidative damage in human vascular endothelial cells by upregulating Bcl-2.

BACKGROUND: 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) have been widely used in clinical practise and their efficacy in reducing cardiovascular risk has been well described. OBJECTIVES: To investigate the effect of low doses of fluvastatin (nanomolar) on H(2)O(2)-induced cell damage and the underlying mechanism. METHODS AND RESULTS: Primary cultures of human umbilical vein endothelial cells were used, and the effects of fluvastatin on H(2)O(2)-induced apoptosis, necrosis, and proliferation were observed. H(2)O(2) at a concentration of 100 mum significantly induced apoptotic cell death after 24-h cell culture. Fluvastatin at low concentrations (10-100 nm) prevented H(2)O(2)-induced apoptosis, as determined by a DNA fragmentation assay and by cell counting with trypan blue and Hoechst 33342 nuclei staining. The protective effect of fluvastatin was mediated by the upregulation of Bcl-2 expression as probed by real-time polymerase chain reaction and Western blotting. Using siRNA to knock down the expression of Bcl-2, the protective effect of fluvastatin was abolished. Fluvastatin had no direct effect on the H(2)O(2)-sensitive TRPM2 calcium channel. CONCLUSIONS: These results suggest that fluvastatin has a potent protective effect against H(2)O(2)-induced apoptosis via upregulation of Bcl-2 expression. The findings provide a new insight into the mechanism by which fluvastatin is able to modulate the influence of oxidative stress on vascular endothelial cells.

Mutations of phosphatase and tensin homolog deleted from chromosome 10 in canine hemangiosarcoma.

We examined the presence of phosphatase and tensin homolog deleted from chromosome 10 (PTEN) abnormalities that could contribute to the origin or progression of naturally occurring canine endothelial tumors (hemangiosarcoma). Our results document somatic point mutations or deletions encompassing the PTEN C-terminal domain in canine hemangiosarcoma that might provide cells a survival advantage within their microenvironment. This represents the first characterization of a naturally occurring, highly metastatic tumor with biologically significant mutations of PTEN in the C-terminal domain.

Thalidomide: dual benefits in palliative medicine and oncology.

Thalidomide is an immunomodulator, anti-angiogenic agent, anti-cytokine, and anti-integrin. Alone or in combination with other drugs, thalidomide has also demonstrated anti-cachexin and anti-neoplastic properties. Anorexia and cachexia are common symptoms of advanced cancer. Since certain cytokines also promote tumor growth, we may have a class of agents with palliative and anti-tumor benefits in combination with anti-neoplastics and anti-cytokines, such as thalidomide.

Strategies for the treatment of cancer pain in the new millennium.

As was the case in the era before us, in the new millennium we will continue to see an abundance of patients experiencing cancer-related pain for different reasons. Although much needless pain and suffering still affects many of those with cancer, we are presented with a medical dichotomy. With the analgesic drugs available today, and the relatively simple and effective guidelines to treat cancer pain published and disseminated by the World Health Organization, why do people with cancer continue to experience pain? As we search for the answer, the horizon may hold promising new drugs, 'old drugs' with new interest and applications, and new strategies for the field of pain therapy. Possibilities include the isolation and development of analgesics or analgesic combinations that may minimise the adverse effects which are often associated with the current therapeutic class of opioid analgesics. In addition, current research points to promising results identifying the N-methyl D-aspartate non-opioid receptor as a likely component of neuropathic pain. Drugs such as gabapentin, the mechanism of action of which is not well known, have found favour within the clinical community for their analgesic properties and good tolerability. Methadone, in a phase of resurgence, has garnered the attention of the clinical community because of its unique receptor activity and pharmacoeconomic benefits. A number of clinical studies have demonstrated that methadone has a valuable role in treating cancer pain. Perhaps, an unbalanced focus on the risks of inappropriate use, rather than the benefits, should not compromise or distract from the use of methadone as an alternative to morphine. Studies are on going to assess the potential role of methadone in treating neuropathic pain. Drugs such as cannabinoids, although currently applicable for patients with anorexia, nausea and/or vomiting, may offer benefits to patients experiencing pain. Other opportunities exist with such compounds as alpha2-adrenergic agonists, nicotine, lidocaine and ketamine. New strategies such as the switching opioids and/or their route of administration may offer improved analgesia with fewer adverse effects, thus providing therapeutic alternatives for the clinical community. In addition, there is interest in the co-administration of opioids that act on different receptors. For instance, oxycodone appears to be a kappa opioid receptor agonist and may offer enhanced analgesia when combined with morphine.

Mirtazepine: heir apparent to amitriptyline?

"What's new in therapeutics?" will examine and evaluate drugs that may have a place in hospice, palliative, and long-term care. Mirtazepine will be examined and evaluated. Mirtazepine is a potential alternative anti-depressant with multiple additional benefits. It is an atypical anti-depressant, which has both noradrenergic and specific serotonergic receptor antagonism (NaSSa), and a unique pharmacological profile. Mirtazepine appears to be a "designer drug" for palliative medicine with a number of benefits, but cost may be a drawback.