[New treatment options in system therapy for breast carcinoma and associated new side effects]

INTRODUCTION

Breast cancer today has a significantly better prognosis than two to three decades ago. Treatment options have improved significantly. However, new systemic therapy has also resulted in side effects that clinicians must first become familiar with in order to be able to treat them optimally. This article gives an overview of the most important innovations in the last 10 years in the field of systemic therapy in breast cancer and also shows the most important side effects and their management.

Circulating Tumor Cell Clustering Shapes DNA Methylation to Enable Metastasis Seeding

The ability of circulating tumor cells (CTCs) to form clusters has been linked to increased metastatic potential. Yet biological features and vulnerabilities of CTC clusters remain largely unknown. Here, we profile the DNA methylation landscape of single CTCs and CTC clusters from breast cancer patients and mouse models on a genome-wide scale. We find that binding sites for stemness- and proliferation-associated transcription factors are specifically hypomethylated in CTC clusters, including binding sites for OCT4, NANOG, SOX2, and SIN3A, paralleling embryonic stem cell biology. Among 2,486 FDA-approved compounds, we identify Na⁺/K⁺ ATPase inhibitors that enable the dissociation of CTC clusters into single cells, leading to DNA methylation remodeling at critical sites and metastasis suppression. Thus, our results link CTC clustering to specific changes in DNA methylation that promote stemness and metastasis and point to cluster-targeting compounds to suppress the spread of cancer.

Denosumab treatment is associated with the absence of circulating tumor cells in patients with breast cancer

Background

The presence of circulating tumor cells (CTCs) in patients with breast cancer correlates to a bad prognosis. Yet, CTCs are detectable in only a minority of patients with progressive breast cancer, and factors that influence the abundance of CTCs remain elusive.

Methods

We conducted CTC isolation and enumeration in a selected group of 73 consecutive patients characterized by progressive invasive breast cancer, high tumor load and treatment discontinuation at the time of CTC isolation. CTCs were quantified with the Parsortix microfluidic device. Clinicopathological variables, blood counts at the time of CTC isolation and detailed treatment history prior to blood sampling were evaluated for each patient.

Results

Among 73 patients, we detected at least one CTC per 7.5 ml of blood in 34 (46%). Of these, 22 (65%) had single CTCs only, whereas 12 (35%) featured both single CTCs and CTC clusters. Treatment with the monoclonal antibody denosumab correlated with the absence of CTCs, both when considering all patients and when considering only those with bone metastasis. We also found that low red blood cell count was associated with the presence of CTCs, whereas high CA 15-3 tumor marker, high mean corpuscular volume, high white blood cell count and high mean platelet volume associated specifically with CTC clusters.

Conclusions

In addition to blood count correlatives to single and clustered CTCs, we found that denosumab treatment associates with most patients lacking CTCs from their peripheral circulation. Prospective studies will be needed to validate the involvement of denosumab in the prevention of CTC generation.

Electronic supplementary material

The online version of this article (10.1186/s13058-018-1067-y) contains supplementary material, which is available to authorized users.

Timing of surgical antimicrobial prophylaxis: a phase 3 randomised controlled trial

BACKGROUND

Based on observational studies, administration of surgical antimicrobial prophylaxis (SAP) for the prevention of surgical site infection (SSI) is recommended within 60 min before incision. However, the precise optimum timing is unknown. This trial compared early versus late administration of SAP before surgery.

METHODS

In this phase 3 randomised controlled superiority trial, we included general surgery adult inpatients (age ≥18 years) at two Swiss hospitals in Basel and Aarau. Patients were randomised centrally and stratified by hospital according to a pre-existing computer-generated list in a 1:1 ratio to receive SAP early in the anaesthesia room or late in the operating room. Patients and the outcome assessment team were blinded to group assignment. SAP consisted of single-shot, intravenous infusion of 1·5 g of cefuroxime, a commonly used cephalosporin with a short half-life, over 2-5 min (combined with 500 mg metronidazole in colorectal surgery). The primary endpoint was the occurrence of SSI within 30 days of surgery. The main analyses were by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT01790529.

FINDINGS

Between Feb 21, 2013, and Aug 3, 2015, 5580 patients were randomly assigned to receive SAP early (2798 patients) or late (2782 patients). 5175 patients (2589 in the early group and 2586 in the late group) were analysed. Median administration time was 42 min before incision in the early group (IQR 30-55) and 16 min before incision in the late group (IQR 10-25). Inpatient follow-up rate was 100% (5175 of 5175 patients); outpatient 30-day follow-up rate was 88·8% (4596 of 5175), with an overall SSI rate of 5·1% (234 of 4596). Early administration of SAP did not significantly reduce the risk of SSI compared with late administration (odds ratio 0·93, 95% CI 0·72-1·21, p=0·601).

INTERPRETATION

Our findings do not support any narrowing of the 60-min window for the administration of a cephalosporin with a short half-life, thereby obviating the need for increasingly challenging SAP timing recommendations.

FUNDING

Swiss National Science Foundation, Hospital of Aarau, University of Basel, Gottfried und Julia Bangerter-Rhyner Foundation, Hippocrate Foundation, and Nora van Meeuwen-Häfliger Foundation.

Lymph Node Surgery - Stepwise Retirement for the Breast Surgeon?

Axillary lymph node dissection (ALND) has been standard of care for all patients with breast cancer until the 1990s. The stepwise retreat of breast surgeons from the axilla began after the introduction of the sentinel lymph node procedure. The evidence based clinical trend toward the omission of ALND has advanced to include patients with affected nodes, and several ongoing randomized controlled trials are evaluating the remaining indications for ALND. Conflicting with this trend toward less axillary surgery, indication and extent of regional nodal irradiation are currently broadened, equally supported by evidence from randomized trials. The present review summarizes this conflicting evidence, presents ongoing trials, and discusses the current and future optimal regional management of patients with affected nodes.

Structural circular birefringence and dichroism quantified by differential decomposition of spectroscopic transmission Mueller matrices from Cetonia aurata

Transmission Mueller-matrix spectroscopic ellipsometry is applied to the cuticle of the beetle Cetonia aurata in the spectral range 300-1000 nm. The cuticle is optically reciprocal and exhibits circular Bragg filter features for green light. By using differential decomposition of the Mueller matrix, the circular and linear birefringence as well as dichroism of the beetle cuticle are quantified. A maximum value of structural optical activity of 560°/mm is found.

Etiological Observations in Seven Patients with Pancreatic Neuroendocrine Tumors (PNETs)

BACKGROUND/AIM

Pancreatic neuroendocrine tumors (PNETs) are uncommon malignancies of largely unknown pathogenesis. Observations on patients and their families can provide clues on etiology.

PATIENTS AND METHODS

In a medical oncology practice cohort of 2,087 patients 5 females and 2 males with PNETs have been identified.

RESULTS

Observations of etiologic interest have been made in 2 patients with PNETs. One female patient belongs to a kidney cancer family with a balanced translocation t(3;11)(q13;q21). A second female patient with PNET had a de novo translocation (t3;5)(q27;q14), its braking point could contain a tumor suppressor gene.

CONCLUSION

Chromosome studies in patients with PNETs point to an etiologic role of balanced translocations.

A six-year study of insect emergence from temporary flooded wetlands in central Sweden, with and without Bti-based mosquito control

In temporary wetlands in the River Dalälven floodplains, recurrent but irregular floods induce massive hatching of the flood-water mosquito Aedes sticticus, which causes enormous nuisance. Flood-water mosquito control using the biological larvicide Bacillus thuringiensis var. israelensis (Bti) was commenced in parts of the floodplains during 2002, and here we report the first six years of full-season monitoring of general insect emergence from temporary wetlands with and without treatment. Emergence traps, which were emptied weekly, were used from May to September each year. A total of 137,153 insects of 13 taxonomic orders were collected. Diptera was highly dominating and especially the sub-order Nematocera with 18 families was a very prominent taxon. Bti-treatment effects were analysed by taxonomic order, by sub-order in Diptera and Hemiptera, and by family for Nematocera and Coleoptera for the whole study period. We found no significant negative effects of Bti treatments on the production of insects by taxonomic order, with the exception of Coleoptera in the long term. However, no significant negative effects were found for the Coleoptera families, neither in the short term nor in the long term. There was no significant negative treatment effect on Nematocera production, neither when analyzed for the whole sub-order nor when analyzed by family. However, abundance of Ceratopogonidae was significantly higher in experimental than in reference wetlands. We conclude that Bti-treatment effects on insect production may be minute in comparison to other environmental factors structuring the insect fauna of the temporary wetlands studied.

Production of wetland Chironomidae (Diptera) and the effects of using Bacillus thuringiensis israelensis for mosquito control

Massive mosquito nuisance problems, caused by the flood-water mosquito Aedes sticticus, occur after floods in the flood plains of the River Dalälven, central Sweden. Since 2002, the biological mosquito larvicide Bacillus thuringiensis var. israelensis (Bti) has been used to control these mosquitoes. Here, we report results from the first six years of monitoring Chironomidae, the most susceptible non-target organisms, in three wetlands with Bti-treatment against mosquitoes and in three wetlands without treatment. Emergence traps were used for continuous insect sampling from May to September each year, 2002-2007, and were emptied once a week. A total of 21,394 chironomids of 135 species were collected, and the subfamily Orthocladiinae dominated the fauna followed by Chironominae and Tanypodinae. The annual chironomid production in the wetlands was low, with an average of 1917 individuals per m(2), and 42 g ash-free dry weight per m(2). We found no reduced production of chironomids at neither family, nor subfamily level, in Bti-treated as compared to untreated wetlands. This is the first long-term follow-up study of the possible effects of Bti-based mosquito larval control on chironomid species production. In the short-term view, one species had higher production in treated areas. In the long-term view, four species had higher and one species had lower production in treated areas. We conclude that the Bti-based control of flood-water mosquitoes does not cause any major direct negative effects on chironomid production, and therefore does not seem to induce any risk for indirect negative effects on birds, bats or any other predators feeding on chironomids.

Use of alternative therapies in patients with dementia and mild cognitive impairment: a prospective, controlled study

OBJECTIVES

To study the frequency and type of alternative therapies used in patients with dementia and Mild Cognitive Impairment.

METHODS

In a prospective study, 77 outpatients and 62 healthy volunteers were interviewed using a questionnaire concerning frequency, type and motivation of the use of alternative therapies.

RESULTS

47% of patients and 18% of control subjects used alternative therapies to treat or prevent disturbances of memory (p < 0.001). No correlation could be found between use of alternative medicine and professional education, severity of disease, religion or health insurance status (p > 0.05). The most commonly used substances were vitamins. Side effects remained unreported. 52% of patients were treated with conventional medications. Only 44% of the patients informed their physician about the use of alternative medicine.

CONCLUSIONS

The use of alternative therapies, particularly vitamins, and herbal preparations of unknown efficacy is common among patients with dementia and MCI. Hence, the treating physician should actively inquire about their use as some preparations have pharmacological activity or could interact with other prescribed medications.

Biological diversity versus risk for mosquito nuisance and disease transmission in constructed wetlands in southern Sweden

In southern Sweden, many wetlands have been constructed, and maintaining or increasing biological diversity is often included in the aims. Some wetlands are constructed near human settlements, thus raising the problem of wetlands being associated with mosquitoes (Diptera: Culicidae). Increased biodiversity (including mosquito diversity) is considered desirable, whereas mosquito nuisance from a human point of view is not. Adult mosquito abundance, diversity and species assemblages of constructed wetlands were compared to natural wetlands. The potential of constructed wetlands for mosquito nuisance and transmission of mosquito-borne viruses was evaluated. The study areas included five constructed and four natural wetlands. Mosquito abundance and species richness were higher in the natural than in the constructed wetlands, and showed a positive correlation with wetland size. Mosquito species assemblages formed three clusters, which were not explained by origin, size and water permanence of wetlands. In a redundancy analysis, however, mosquito faunas showed significant relationships with these variables, and size and origin of wetlands were most important. Major nuisance species (multivoltine species feeding on mammals and laying eggs on soil) were found in all wetlands, although in relatively low numbers. Risk assessment for Sindbis virus transmission showed moderate risk for two constructed wetlands near human settlements. It is concluded that small size of constructed wetlands has the advantage of low mosquito numbers from a human point of view. The use of functional groups is recommended as a tool for presenting mosquito data to the public, and for helping communication between scientists and administrative decision makers.

Diving beetles (Dytiscidae) as predators of mosquito larvae (Culicidae) in field experiments and in laboratory tests of prey preference

Field experiments were performed in artificial ponds to evaluate how the density of predatory diving beetles (Dytiscidae) would affect the population levels of mosquito larvae (Culicidae). Mosquitoes colonizing the ponds were predominantly species of the genus Culex. In 2000, most of the dytiscids colonizing the ponds were small (Hydroporus spp.), and these predators had no impact on the size of larval mosquito populations, not even in ponds with added dytiscids. In 2001, larger beetles (Ilybius, Rhantus, and Agabus spp.) were more common, and there were significantly fewer mosquito larvae in ponds with the highest numbers of dytiscids. There was a negative correlation between numbers of diving beetles in the ponds and the mean body length of mosquito larvae. In neither year could dytiscid densities be maintained above a certain level owing to emigration. In laboratory tests, there were marked differences between three common dytiscid species in regard to preferences for Daphnia and Culex species as prey: Colymbetes paykulli Erichson chose mosquito larvae more often, whereas both Ilybius ater (De Geer) and I. fuliginosus (Fabricius) preferred Daphnia spp. All of the tested dytiscids consumed large numbers of prey. Since some dytiscid species can efficiently decrease populations of mosquito larvae, they are probably important in the natural control of these dipterans.

The cytoplasmic helix of cannabinoid receptor CB2, a conformational study by circular dichroism and (1)H NMR spectroscopy in aqueous and membrane-like environments

The cytoplasmic helix domain (fourth cytoplasmic loop, helix 8) of numerous G protein-coupled receptors (GPCRs) such as rhodopsin and the beta-adrenergic receptor exhibit unique structural and functional characteristics. Computer models also predict this structure for the cannabinoid CB2 receptor, another member of the GPCR superfamily. In our study, a peptide corresponding to helix 8 of the CB2 receptor was synthesized chemically and its secondary structure determined by circular dichroism (CD) and (1)H NMR spectroscopy. NMR and CD revealed an alpha-helical structure in this region in both dodecylphosphocholine micelles and dimethylsulfoxide, in contrast to a random coil configuration found in aqueous solvent. This finding is in good agreement with other previous GPCR structural studies including X-ray crystallography. By combining our finding with other studies, we further hypothesize that the amphipathic nature of helix 8 can play a significant role in the function and regulation of CB receptors as well as other GPCRs in general.