MicroRNA Expression Profiling of Peripheral Blood Samples Predicts Resistance to First-line Sunitinib in Advanced Renal Cell Carcinoma Patients

Anti-angiogenic therapy benefits many patients with advanced renal cell carcinoma (RCC), but there is still a need for predictive markers that help in selecting the best therapy for individual patients. MicroRNAs (miRNAs) regulate cancer cell behavior and may be attractive biomarkers for prognosis and prediction of response. Forty-four patients with RCC were recruited into this observational prospective study conducted in nine Spanish institutions. Peripheral blood samples were taken before initiation of therapy and 14 days later in patients receiving first-line therapy with sunitinib for advanced RCC. miRNA expression in peripheral blood was assessed using microarrays and L2 boosting was applied to filtered miRNA expression data. Several models predicting poor and prolonged response to sunitinib were constructed and evaluated by binary logistic regression. Blood samples from 38 patients and 287 miRNAs were evaluated. Twenty-eight miRNAs of the 287 were related to poor response and 23 of the 287 were related to prolonged response to sunitinib treatment. Predictive models identified populations with differences in the established end points. In the poor response group, median time to progression was 3.5 months and the overall survival was 8.5, whereas in the prolonged response group these values were 24 and 29.5 months, respectively. Ontology analyses pointed out to cancer-related pathways, such angiogenesis and apoptosis. miRNA expression signatures, measured in peripheral blood, may stratify patients with advanced RCC according to their response to first-line therapy with sunitinib, improving diagnostic accuracy. After proper validation, these signatures could be used to tailor therapy in this setting.     

Hyperbaric oxygen therapy for nonischemic diabetic ulcers: A systematic review

Diabetic foot ulcers are a common complication of diabetes, which affects 25% of patients and may ultimately lead to amputation of affected limbs. Research suggests hyperbaric oxygen therapy improves healing of these ulcers. However, this has not been reflected in previous reviews, possibly because they did not differentiate between patients with and without peripheral arterial occlusive disease. Therefore, we performed a systematic review of published literature in the MEDLINE, Embase, and Cochrane CENTRAL databases on nonischemic diabetic foot ulcers with outcome measures including complete ulcer healing, amputation rate (major and minor), and mortality. Seven studies were included, of which two were randomized clinical trials. Two studies found no difference in major amputation rate, whereas one large retrospective study found 2% more major amputations in the hyperbaric oxygen group. However, this study did not correct for baseline differences. Two studies showed no significant difference in minor amputation rate. Five studies reporting on complete wound healing showed no significant differences. In conclusion, the current evidence suggests that hyperbaric oxygen therapy does not accelerate wound healing and does not prevent major or minor amputations in patients with a diabetic foot ulcer without peripheral arterial occlusive disease. Based on the available evidence, routine clinical use of this therapy cannot be recommended. However, the available research for this specific subgroup of patients is scarce, and physicians should counsel patients on expected risks and benefits. Additional research, focusing especially on patient selection criteria, is needed to better identify patients that might profit from this therapy modality.     

11C]flumazenil metabolite measurement in plasma is not necessary for accurate brain benzodiazepine receptor quantification

In this work, a mathematical correction for metabolites has been validated which estimates the relative amount of [11C]flumazenil ([11C]FMZ) in the total plasma curve from the tissue kinetic data without the need for direct metabolite measurement in blood plasma samples. Kinetic data were obtained using a 90-min three-injection protocol on five normal volunteers. First, the relative amount of [11C]FMZ in plasma was modelled by a two-parameter exponential function. The parameters were estimated either directly by fitting this model to the blood plasma metabolite measurements, or indirectly from the simultaneous fitting of tissue time activity curves from several brain regions with a non-linear FMZ kinetic model. Second, the direct and indirect metabolite corrections were fixed and the FMZ compartmental parameters were determined on a regional basis in the brain. The validation was performed by comparing the regional values of benzodiazepine receptor density Bmax and equilibrium dissociation constant Kd obtained with the direct metabolite correction with those values obtained with the indirect correction. For Bmax, the correlation coefficient r2 was above 0.97 for all subjects and the slope values of the linear regression were within the interval [0.97, 1.2]. For Kd, r2 was above 0.96, and the slope values of the linear regression were within the interval [0.99, 1.1]. Simulation studies were performed in order to evaluate whether this metabolite correction method could be used in a clinical protocol where only a single [11C]FMZ injection and a linear compartmental model are used. The resulting [11C]FMZ distribution volume estimates were found to be linearly correlated with the true values, with r2=1.0 and a slope value of 1.1. The mathematical metabolite correction proved to be a feasible and reliable method to estimate the relative amount of [11C]FMZ in plasma and the compartmental model parameters for three-injection protocols. Although validation with real data is necessary, simulation results suggest that our analysis method may also be applied to single-injection protocols.     

Treatment of Clinically Positive Cervical Lymph Nodes by Limited Local Node Excision and Adjuvant Radiotherapy in Melanoma Patients with Major Comorbidities

Introduction

When cervical lymph nodes are clinically positive for metastatic melanoma, surgeons may be hesitant to recommend a therapeutic complete lymph node dissection if the patient is elderly or has major comorbidities. A limited local node excision of the clinically positive nodes only, followed by adjuvant radiotherapy to the entire node field, may be an effective alternative in such patients.

Methods

All patients who had presented with a primary head and neck melanoma or an unknown primary site and had subsequently undergone limited local node excision and adjuvant radiotherapy for macroscopically involved cervical nodes between 1993 and 2010 at a tertiary referral center were selected for study.

Results

Twenty-eight patients were identified, with a median age of 78 years and a median of 2 major comorbidities. The 5-year regional control, disease-free survival, and overall survival rates were 69%, 44%, and 50%, respectively. At the time of data analysis, seven patients were alive without evidence of disease. Twenty-one patients had died: 11 of melanoma (4 with neck recurrence) and 10 of other causes (2 with neck recurrence).

Conclusions

Excision of clinically positive metastatic cervical lymph nodes followed by radiotherapy provides satisfactory regional disease control without risking serious morbidity or mortality in melanoma patients whose general condition is considered a contraindication for therapeutic complete lymph node dissection.

     

Susceptibility to six antibiotics of group B streptococci isolated from cerebrospinal fluid

64 clinical isolates of group B streptococci from cerebrospinal fluids of neonates were tested for susceptibility to 6 antibiotics. The strains were obtained in The Netherlands during 7 years. The usefulness of the generally recommended initial therapy, a combination of ampicillin and gentamicin, is supported.     

Nematode transmission of tobacco rattle virus serves as a bottleneck to clear the virus population from defective interfering RNAs.

DI7 is a defective interfering RNA derived from RNA 2 of tobacco rattle tobravirus (TRV) isolate PpK20. Tobacco was transformed with DI7 cDNA fused to the CaMV 35S promoter. Upon infection of the transgenic plants with TRV isolate PpK20 or the serologically unrelated isolate PaY4, the transgenic DI7 RNA started to accumulate at high levels and strongly interfered with accumulation of wild-type (wt) RNA 2. When DI7 transgenic plants infected with isolate PpK20 were used as source plants in nematode-transmission experiments, the vector Paratrichodorus pachydermus efficiently transmitted virus to healthy bait plants. However, the nematodes transmitted only the wt virus present in the transgenic source plants, whereas virus particles containing the abundant, accumulated DI7 RNA were excluded from transmission. Evidence is presented that wt RNA 2 and DI7 RNA are encapsidated in cis by their encoded CPs, which are known to be functional and nonfunctional in transmission, respectively. This mechanism would result in defective interfering RNAs, which rapidly arise after mechanical transmission of the virus in the laboratory, being eliminated from tobraviruses under natural field conditions. Also this mechanism which acts with nematode transmitted virus isolates contrasts with that of vector-transmission of defective potyviruses and luteoviruses by wt helper viruses.     

Distinct immunomodulation by autoimmunogenic xenobiotics in susceptible and resistant mice.

HgCl(2) and diphenylhydantoin (DPH) are prototype chemicals associated with diverse (auto)immune effects in genetically susceptible individuals. Both chemicals activate T cells, and the balance of Th1 versus Th2 activation may influence the clinical outcome of exposure. It is unknown which chemically created neoantigens are responsible for Th activation. We therefore investigated the effect of DPH and HgCl(2) on specific responses to TNP-ovalbumin, in mouse strains with varying sensitivity for the adverse effects. HgCl(2) was found to enhance Th2-driven antibody responses in susceptible B10.s, but protective type 1 responses in resistant B10.d2 mice. This was chemical-specific, as DPH enhanced type 2 responses in both strains. DBA/2 mice were relatively unresponsive to HgCl(2), whereas DPH stimulated type 1 responses in these mice. Interestingly, prior exposure to HgCl(2), but not DPH, facilitated IC deposition in B10.s mice only. Thus, we demonstrate that, depending on MHC-II and background genes, HgCl(2) and DPH preferentially adjuvate type 1 or type 2 responses. In case of HgCl(2), the type of response corresponds with susceptibility to antibody-mediated autoimmunity induced by this chemical. In addition, we demonstrate that, within one strain, different autoimmunogenic chemicals can enhance distinct responses to the same antigen.     

Structural abnormalities of chromosome 2 in benign thyroid tumors. Three new cases and review of the literature.

Here we report our cytogenetic findings on three cases of nodular goiter, all showing structural clonal abnormalities of chromosome 2. In the first case, we found a t(2;3)(q21;q27 or q28) in two nodules of the same patient. The second case revealed a t(2;20;3)(p21;q11.2;p25), and the third case showed a t(1;2)(p22;p13). When the data from the literature and the present cases are summarized, the results suggest the existence of at least three breakpoint clusters of chromosome 2 in benign thyroid tumors or hyperplasias.     

Using Cognitive and Affective Illustrations to Enhance Older Adults’ Website Satisfaction and Recall of Online Cancer-Related Information

This study examined the effect of adding cognitive and affective illustrations to online health information (vs. text only) on older adults’ website satisfaction and recall of cancer-related information. Results of an online experiment among younger and older adults showed that illustrations increased satisfaction with attractiveness of the website. Younger adults were significantly more satisfied with the comprehensibility of the website than older adults, whereas older adults were more satisfied with perceived emotional support from the website than younger adults. Being more emotionally satisfied with the website led to greater recall of information for older adults, but not for younger adults. Illustrations can be used to enhance older adults’ website satisfaction and consequently recall of online cancer-related information.     

Influence of methanandamide and CGRP on potassium currents in smooth muscle cells of small mesenteric arteries

Cannabinoids have potent vasodilatory actions in a variety of vascular preparations. Their mechanism of action, however, is complex. Apart from acting on vascular smooth muscle or endothelial cannabinoid receptors, several studies point to the activation of type 1 vanilloid (TRPV1) receptors on primary afferent perivascular nerves, stimulating the release of calcitonin gene-related peptide (CGRP). In the present study, the direct influence of the cannabinoid methanandamide and the neuropeptide CGRP on the membrane potassium ion (K⁺) currents of rat mesenteric myocytes was explored. Methanandamide (10 μM) decreased outward K⁺ currents, an effect similar to that observed in smooth muscle cells from the rat aorta. Conversely, CGRP (10 nM) significantly increased whole-cell K⁺ currents and this effect was abolished by preexposure to tetraethylammonium chloride (1 mM) or iberiotoxin (100 nM), inhibitors of large-conductance calcium-dependent K (BK_Ca) channels but not by glibenclamide (10 μM), an inhibitor of ATP-dependent K channels. In the presence of the CGRP receptor antagonist CGRP_8-37 (100 nM), the adenylyl cyclase inhibitor SQ22536 (100 μM), or the protein kinase A inhibitor Rp-cAMPS (10 μM), CGRP had no effect. These findings show that methanandamide does not increase membrane K⁺ currents in smooth muscle cells of small mesenteric arteries, supporting an indirect mechanism for the reported hyperpolarizing influence in this vessel. Moreover, CGRP acts directly on these smooth muscle cells by increasing BK_Ca channel activity in a CGRP receptor and cyclic adenosine monophosphate-dependent way. Collectively, these data indicate that methanandamide relaxes and hyperpolarizes intact mesenteric vessels by releasing CGRP from perivascular nerves.