BRD4 inhibition sensitizes diffuse large B-cell lymphoma cells to ferroptosis.

Diffuse large B-cell lymphoma (DLBCL), the most common form of non-Hodgkin lymphoma, is characterized by an aggressive clinical course. In approximately one-third of patients with DLBCL, first-line multiagent immunochemotherapy fails to produce a durable response. Molecular heterogeneity and apoptosis resistance pose major therapeutic challenges in DLBCL treatment. To circumvent apoptosis resistance, the induction of ferroptosis might represent a promising strategy for lymphoma therapy. In this study, a compound library, targeting epigenetic modulators, was screened to identify ferroptosis-sensitizing drugs. Strikingly, bromodomain and extra-terminal domain (BET) inhibitors sensitized cells of the germinal center B-cell-like (GCB) subtype of DLBCL to ferroptosis induction and the combination of BET inhibitors with ferroptosis inducers, such as dimethyl fumarate or RSL3, synergized in the killing of DLBCL cells in vitro and in vivo. On the molecular level, the BET protein BRD4 was found to be an essential regulator of ferroptosis suppressor protein 1 expression and thus to protect GCB-DLBCL cells from ferroptosis. Collectively, we identified and characterized BRD4 as an important player in ferroptosis suppression in GCB-DLBCL and provide a rationale for the combination of BET inhibitors with ferroptosis-inducing agents as a novel therapeutic approach for DLBCL treatment.

Patient-reported outcomes in advanced NSCLC before and during the COVID-19 pandemic: Real-world data from the German prospective CRISP Registry (AIO-TRK-0315).

Patients with lung cancer under treatment have been associated with a high risk of COVID-19 infection and potentially worse outcome, but real-world data on patient-reported outcomes (PROs) are rare. We assess patients' characteristics and PROs before and during the COVID-19 pandemic in an advanced non-small cell lung cancer (NSCLC) cohort in Germany. Patients with locally advanced or metastatic NSCLC from the prospective, multicentre, observational CRISP Registry (NCT02622581) were categorised as pre-pandemic (March 2019 to Feb 2020, n = 1621) and pandemic (March 2020 to Feb 2021, n = 1317). From baseline to month 15, patients' health-related quality of life (HRQoL) was assessed by FACT-L, anxiety and depression by PHQ-4. Association of pandemic status with time to deterioration (TTD) in QoL scales adjusted for potential covariates was estimated using Cox modelling. PROs were documented for 1166 patients (72%) in the pre-pandemic, 979 (74%) in the pandemic group. Almost 60% of patients were male, median age was 66 years, comorbidities occurred in 85%. Regarding HRQoL, mean-change-from-baseline plots hardly differed between both samples. Approximately 15%-21% of patients reported anxiety, about 19%-27% signs of depression. For the pandemic group, TTD was slightly, but statistically significantly, worse for the physical well-being-FACT-G subscale (HR 1.15 [95%CI 1.02-1.30]) and the anxiety-GAD-2 subscale (HR 1.14 [95%CI 1.01-1.29]). These prospectively collected real-world data provide valuable insights into PROs before and during the COVID-19 pandemic in advanced NSCLC. For the patients, the pandemic seemed to be less of a burden than the disease itself, as there was a considerable proportion of patients with anxiety and depression in both groups.

A novel method to efficiently differentiate human osteoclasts from blood-derived monocytes.

BACKGROUND: Osteoclasts are the tissue-specific macrophage population of the bone and unique in their bone-resorbing activity. Hence, they are fundamental for bone physiology in health and disease. However, efficient protocols for the isolation and study of primary human osteoclasts are scarce. In this study, we aimed to establish a protocol, which enables the efficient differentiation of functional human osteoclasts from monocytes. RESULTS: Human monocytes were isolated through a double-density gradient from donor blood. Compared to standard differentiation schemes in polystyrene cell culture dishes, the yield of multinuclear osteoclasts was significantly increased upon initial differentiation of monocytes to macrophages in fluorinated ethylene propylene (FEP) Teflon bags. This initial differentiation phase was then followed by the development of terminal osteoclasts by addition of Receptor Activator of NF-κB Ligand (RANKL). High concentrations of RANKL and Macrophage colony-stimulating factor (M-CSF) as well as an intermediate cell density further supported efficient cell differentiation. The generated cells were highly positive for CD45, CD14 as well as the osteoclast markers CD51/ITGAV and Cathepsin K/CTSK, thus identifying them as osteoclasts. The bone resorption of the osteoclasts was significantly increased when the cells were differentiated from macrophages derived from Teflon bags compared to macrophages derived from conventional cell culture plates. CONCLUSION: Our study has established a novel protocol for the isolation of primary human osteoclasts that improves osteoclastogenesis in comparison to the conventionally used cultivation approach.

Molecular differences of angiogenic versus vessel co-opting colorectal cancer liver metastases at single-cell resolution.

BACKGROUND: Colorectal cancer liver metastases (CRCLM) are associated with a poor prognosis, reflected by a five-year survival rate of 14%. Anti-angiogenic therapy through anti-VEGF antibody administration is one of the limited therapies available. However, only a subgroup of metastases uses sprouting angiogenesis to secure their nutrients and oxygen supply, while others rely on vessel co-option (VCO). The distinct mode of vascularization is reflected by specific histopathological growth patterns (HGPs), which have proven prognostic and predictive significance. Nevertheless, their molecular mechanisms are poorly understood. METHODS: We evaluated CRCLM from 225 patients regarding their HGP and clinical data. Moreover, we performed spatial (21,804 spots) and single-cell (22,419 cells) RNA sequencing analyses to explore molecular differences in detail, further validated in vitro through immunohistochemical analysis and patient-derived organoid cultures. RESULTS: We detected specific metabolic alterations and a signature of WNT signalling activation in metastatic cancer cells related to the VCO phenotype. Importantly, in the corresponding healthy liver of CRCLM displaying sprouting angiogenesis, we identified a predominantly expressed capillary subtype of endothelial cells, which could be further explored as a possible predictor for HGP relying on sprouting angiogenesis. CONCLUSION: These findings may prove to be novel therapeutic targets to the treatment of CRCLM, in special the ones relying on VCO.

Reduction of tumor volume during radiotherapy in patients with small-cell lung cancer and its prognostic significance.

BACKGROUND: Several studies have reported the potential prognostic significance of tumor volume reduction ratio (VRR) induced by radiotherapy (RT) in patients with non-small-cell lung cancer. However, there are no data yet on the prognostic significance of volumetric shrinkage in patients with small-cell lung cancer (SCLC). This study aimed to demonstrate the correlation between tumor volume reduction ratio and treatment outcomes. MATERIALS AND METHODS: The study included 61 patients with SCLC treated with fractionated RT of the primary tumor at our institution between 2013 and 2020. The relationship between volumetric changes in gross tumor volume (GTV) during radiotherapy and outcomes were analyzed and reported. RESULTS: The median radiation dose was 59.4 Gy (median fraction dose was 1.8 Gy). The median GTV before radiotherapy was 74 cm3, with a median GTV reduction of 48%. There was a higher VRR in patients receiving concurrent radiochemotherapy (p = 0.05). No volumetric parameters were identified as relevant predictors of outcome in the entire cohort. In multivariate analysis, only age had an impact on survival, while prophylactic whole-brain radiation influenced the progression-free survival significantly. CONCLUSION: Concurrent chemotherapy was associated with a higher VRR than sequential chemotherapy. No significant impact of VRR on patients' outcome or survival was detected.

Extracellular vesicle-associated tyrosine kinase-like orphan receptors ROR1 and ROR2 promote breast cancer progression.

BACKGROUND: Extracellular vesicles (EVs) harbor a plethora of different biomolecules, which they can transport across cells. In cancer, tumor-derived EVs thereby support the creation of a favorable tumor microenvironment. So far, EV uptake and cargo delivery into target cells have been regarded as the main mechanisms for the pro-tumoral function of EVs. To test this hypothesis, we investigated the fate of the oncogenic transmembrane Wnt tyrosine kinase-like orphan receptor 1 and 2 (ROR1, ROR2) delivered via distinct EV subpopulations to breast cancer cells and aimed to unravel their impact on tumor progression. METHODS: EVs were isolated by differential ultracentrifugation from cell culture supernatant as well as plasma samples from healthy individuals (n = 27) and breast cancer patients (n = 41). EVs were thoroughly characterized by electron microscopy, nanoparticle tracking analysis, immunoblot, and flow cytometry. ROR transfer to target cells was observed using microscopy-based assays and biodistribution experiments were conducted in syngeneic mice. EV impact on cancer cell migration and invasion was tested in functional assays. RESULTS: We observed that the supernatant of ROR-overexpressing cells was sufficient for transferring the receptors to ROR-negative cells. Analyzing the secretome of the ROR-overexpressing cells, we detected a high enrichment of ROR1/2 on large and small EVs, but not on large oncosomes. Interestingly, the majority of ROR-positive EVs remained attached to the target cell surface after 24 h of stimulation and was quickly removed by treatment with trypsin. Nonetheless, ROR-positive EVs increased migration and invasion of breast cancer cells, even after chemically inhibiting EV uptake, in dependence of RhoA downstream signaling. In vivo, ROR-depleted EVs tended to distribute less into organs prone for the formation of breast cancer metastases. ROR-positive EVs were also significantly elevated in the plasma of breast cancer patients and allowed to separate them from healthy controls. CONCLUSIONS: The oncogenic Wnt receptors ROR1/2 are transferred via EVs to the surface of ROR-negative cancer cells, in which they induce an aggressive phenotype supporting tumor progression. Video Abstract.

Surgery for brain metastases: radiooncology scores predict survival-score index for radiosurgery, graded prognostic assessment, recursive partitioning analysis.

BACKGROUND: Radiooncological scores are used to stratify patients for radiation therapy. We assessed their ability to predict overall survival (OS) in patients undergoing surgery for metastatic brain disease. METHODS: We performed a post-hoc single-center analysis of 175 patients, prospectively enrolled in the MetastaSys study data. Score index of radiosurgery (SIR), graded prognostic assessment (GPA), and recursive partitioning analysis (RPA) were assessed. All scores consider age, systemic disease, and performance status prior to surgery. Furthermore, GPA and SIR include the number of intracranial lesions while SIR additionally requires metastatic lesion volume. Predictive values for case fatality at 1 year after surgery were compared among scoring systems. RESULTS: All scores produced accurate reflections on OS after surgery (p ≤ 0.003). Median survival was 21-24 weeks in patients scored in the unfavorable cohorts, respectively. In cohorts with favorable scores, median survival ranged from 42 to 60 weeks. Favorable SIR was associated with a hazard ratio (HR) of 0.44 [0.29, 0.66] for death within 1 year. For GPA, the HR amounted to 0.44 [0.25, 0.75], while RPA had a HR of 0.30 [0.14, 0.63]. Overall test performance was highest for the SIR. CONCLUSIONS: All scores proved useful in predicting OS. Considering our data, we recommend using the SIR for preoperative prognostic evaluation and counseling.

Complete Metabolic Response to Combined Immune Checkpoint Inhibition after Progression of Metastatic Colorectal Cancer on Pembrolizumab: A Case Report.

DNA mismatch repair deficient (dMMR) and microsatellite instable (MSI) metastatic colorectal cancer (mCRC) can be successfully treated with FDA- and EMA-approved immune checkpoint inhibitors (ICI) pembrolizumab and nivolumab (as single agents targeting the anti-programmed cell death protein-1 (PD-1)) or combinations of a PD-1 inhibitor with ipilimumab, a cytotoxic T-lymphocyte-associated protein 4 (CTLA-4)-targeting antibody. The best treatment strategy beyond progression on single-agent ICI therapy remains unclear. Here, we present the case of a 63-year-old male with Lynch-syndrome-associated, microsatellite instability-high (MSI-H) mCRC who achieved a rapid normalization of his tumor markers and a complete metabolic remission (CMR), currently lasting for ten months, on sequential ICI treatment with the combination of nivolumab and ipilimumab followed by nivolumab maintenance therapy after progression on single-agent anti-PD-1 ICI therapy. The therapy was well-tolerated, and no immune-related adverse events occurred. To the best of our knowledge, this is the first case of a sustained metabolic complete remission in an MSI-H mCRC patient initially progressing on single-agent anti-PD-1 therapy. Thus, dMMR mCRC patients might benefit from sequential immune checkpoint regimens even with long-term responses. However, further sophistication of clinical algorithms for treatment beyond progression on single-agent ICI therapy in MSI-mCRC is urgently needed.

"SpezPat"- common advance directives versus disease-centred advance directives: a randomised controlled pilot study on the impact on physicians' understanding of non-small cell lung cancer patients' end-of-life decisions.

BACKGROUND: The advance directive represents patients' health care choices and fosters patients' autonomy. Nevertheless, understanding patients' wishes based on the information provided in advance directives remains a challenge for health care providers. Based on the ethical premises of positive obligation to autonomy, an advanced directive that is disease-centred and details potential problems and complications of the disease should help health care providers correctly understand patients' wishes. To test this hypothesis, a pilot-study was conducted to investigate whether physicians could make the correct end-of-life decision for their patients when patients used a disease-centred advance directive compared to a common advance directive.  MATERIAL AND METHODS: A randomised, controlled, prospective pilot study was designed that included patients with non-small cell lung cancer (NSCLC) stage VI from the Department of Haematology and Medical Oncology, University Medical Centre, Goettingen. Patients were randomised into intervention and control groups. The control group received a common advance directive, and the intervention group received a disease-centred advance directive. Both groups filled out their advance directives and returned them. Subsequently, patients were asked to complete nine medical scenarios with different treatment decisions. For each scenario the patients had to decide whether they wanted to receive treatment on a 5-point Likert scale. Four physicians were given the same scenarios and asked to decide on the treatment according to the patients' wishes as stated in their advance directives. The answers by patients and physicians were then compared to establish whether physicians had made the correct assumptions. RESULTS: Recruitment was stopped prior to reaching anticipated sample target. 15 patients with stage IV NSCLC completed the study, 9 patients were randomised into the control group and 6 patients in the intervention group. A total of 135 decisions were evaluated. The concordance between physicians' and patients' answers, was 0.83 (95%-CI 0.71-0.91) in the intervention group, compared to 0.60 (95%-CI 0.48-0.70) in the control group, and the difference between the two groups was statistically significant (p = 0.005). CONCLUSION: This pilot study shows that disease-centred advance directives help physicians understand their NSCLC patients' wishes more precisely and make treatment choices according to these wishes. TRIAL REGISTRATION: The study is registered at the German Clinical Trial Register (no. DRKS00017580, registration date 27/08/2019).

Impact of myocardial fibrosis on left ventricular remodelling, recovery, and outcome after transcatheter aortic valve implantation in different haemodynamic subtypes of severe aortic stenosis.

AIMS: Myocardial fibrosis (MF) might represent a key player in pathophysiology of heart failure in aortic stenosis (AS). We aimed to assess its impact on left ventricular (LV) remodelling, recovery, and mortality after transcatheter aortic valve implantation (TAVI) in different AS subtypes. METHODS AND RESULTS: One hundred patients with severe AS were prospectively characterized clinically and echocardiographically at baseline (BL), 6 months, 1 year, and 2 years following TAVI. Left ventricular biopsies were harvested after valve deployment. Myocardial fibrosis was assessed after Masson's trichrome staining, and fibrotic area was calculated as percentage of total tissue area. Patients were stratified according to MF above (MF+) or below (MF-) median percentage MF (≥11% or <11%). Myocardial fibrosis burden differed significantly between AS subtypes, with highest levels in low ejection fraction (EF), low-gradient AS and lowest levels in normal EF, high-gradient AS (29.5 ± 26.4% vs. 13.5 ± 16.1%, P = 0.003). In the entire cohort, MF+ was significantly associated with poorer LV function, higher extent of pathological LV remodelling, and more pronounced clinical heart failure at BL. After TAVI, MF+ was associated with a delay in normalization of LV geometry and function but not per se with absence of reverse remodelling and clinical improvement. However, 22 patients died during follow-up (mean, 11 months), and 14 deaths were classified as cardiovascular (CV) (n = 9 arrhythmia-associated). Importantly, 13 of 14 CV deaths occurred in MF+ patients (CV mortality 26.5% in MF+ vs. 2% in MF- patients, P = 0.0003). Multivariate analysis identified MF+ as independent predictor of CV mortality [hazard ratio (HR) 27.4 (2.0-369), P = 0.01]. CONCLUSION: Histological MF is associated with AS-related pathological LV remodelling and independently predicts CV mortality after TAVI.

Metabolomic Profiling of Blood-Derived Microvesicles in Breast Cancer Patients.

Malignant cells differ from benign ones in their metabolome and it is largely unknown whether this difference is reflected in the metabolic profile of their microvesicles (MV), which are secreted into the blood of cancer patients. Here, they are present together with MV from the various blood and endothelial cells. Harvesting MV from 78 breast cancer patients (BC) and 30 controls, we characterized the whole blood MV metabolome using targeted and untargeted mass spectrometry. Especially (lyso)-phosphatidylcholines and sphingomyelins were detected in a relevant abundance. Eight metabolites showed a significant discriminatory power between BC and controls. High concentrations of lysoPCaC26:0 and PCaaC38:5 were associated with shorter overall survival. Comparing BC subtype-specific metabolome profiles, 24 metabolites were differentially expressed between luminal A and luminal B. Pathway analysis revealed alterations in the glycerophospholipid metabolism for the whole cancer cohort and in the ether lipid metabolism for the molecular subtype luminal B. Although this mixture of blood-derived MV contains only a minor number of tumor MV, a combination of metabolites was identified that distinguished between BC and controls as well as between molecular subtypes, and was predictive for overall survival. This suggests that these metabolites represent promising biomarkers and, moreover, that they may be functionally relevant for tumor progression.

Response of eosinophilic fasciitis associated with Waldenström macroglobulinemia to rituximab.

Eosinophilic fasciitis (EF) and generalized morphea (GM) are rare and difficult-to-treat sclerosing skin diseases which may occur in association with hematologic disorders. We present a 66-year-old man with EF and associated Waldenström macroglobulinemia who received combination therapy with rituximab (375mg/m2 every other week, gradually extended to every eight weeks), prednisolone (1.25-30mg/d), and methotrexate (7.5-15mg/w). Three months after rituximab initiation, his skin condition improved steadily accompanied by a significant improvement in joint mobility with only mild and transitory flares (observation period: 59 months under treatment with rituximab). To date, there are five case reports on rituximab treatment of EF/GM with an association to hypergammaglobulinemia in three of those cases. Therapy effected significant improvement in four patients. Our case adds to the hitherto limited evidence that rituximab may be a promising therapeutic strategy for EF/GM in association with hypergammaglobulinemia.

LEF1 supports metastatic brain colonization by regulating glutathione metabolism and increasing ROS resistance in breast cancer.

More than half of all brain metastases show infiltrating rather than displacing growth at the macro-metastasis/organ parenchyma interface (MMPI), a finding associated with shorter survival. The lymphoid enhancer-binding factor-1 (LEF1) is an epithelial-mesenchymal transition (EMT) transcription factor that is commonly overexpressed in brain-colonizing cancer cells. Here, we overexpressed LEF1 in an in vivo breast cancer brain colonization model. It shortened survival, albeit without engaging EMT at the MMPI. By differential proteome analysis, we identified a novel function of LEF1 as a regulator of the glutathione (GSH) system, the principal cellular redox buffer. LEF1 overexpression also conferred resistance against therapeutic GSH depletion during brain colonization and improved management of intracellular ROS. We conclude that besides EMT, LEF1 facilitates metastasis by improving the antioxidative capacity of epithelial breast cancer cells, in particular during colonization of the brain parenchyma.

Impact of pre-OP independence in patients with limited brain metastases on long-term survival.

BACKGROUND: Brain metastasis represents a major complication with a significantly shorter overall survival of many oncological diseases, in particular of lung cancer, breast cancer and malignant melanoma patients. However, despite the poor prognosis, sometimes clinical decision-making, between on the one hand not to harm the patient and on the other hand not withholding a potential therapeutic option, is very challenging. Thus the aim of this retrospective study was to compare various scores, including scores for activities of daily living (ADL) before resection of brain metastases and to analyse their impact on survival. METHODS: Our single institution retrospective patient cohort (N = 100) with a median age of 63.6 years, which had all undergone resection of one or more brain metastases, was categorized using the original patient files. The cohort includes 52 patients with lung cancer, 27 patients with breast cancer, 8 patients with colorectal carcinoma and 13 patients with kidney cancer. To categorize, we used different score systems which were capable to evaluate the patient in relation to self-sufficiency, activity and self-determination as part of ADL. The retrospective analysis includes the ECOG-Status, Karnofsky-Index, Barthel-Index, ASA-Classification and Katz-Index. Pre-processing and the analysis of the data was implemented using KNIME, where we used the R-plugin nodes to perform the final statistical tests with R. RESULTS: Our analysis reveals that most of the ADL scores we tested are able to give a reliable prediction on overall survival after brain metastasis surgery. The survival rates decrease significantly with a lower score in all tested score systems, with the exception of the ASA-Risk score. In particular, the Katz Index < 6 was identified to have a significant correlation with a lower cancer specific survival (CSS) (HR 3.33, 95%-CI [2.17-5.00]; p-Value = 9.6*10- 9), which is easy to use and has reproducible measurements. CONCLUSIONS: Pre-operative independence assessment by indices of ADL represents a predictor for overall survival after resection of brain metastases. Especially the easily, objectively and rapidly applicable Katz-Score is a very helpful tool to assess the pre-operative status, which could be additionally included in clinical decision making in daily practice.

Microvesicles in Cancer: Small Size, Large Potential.

Extracellular vesicles (EV) are secreted by all cell types in a tumor and its microenvironment (TME), playing an essential role in intercellular communication and the establishment of a TME favorable for tumor invasion and metastasis. They encompass a variety of vesicle populations, among them the well-known endosomal-derived small exosomes (Exo), but also larger vesicles (diameter > 100 nm) that are shed directly from the plasma membrane, the so-called microvesicles (MV). Increasing evidence suggests that MV, although biologically different, share the tumor-promoting features of Exo in the TME. Due to their larger size, they can be readily harvested from patients' blood and characterized by routine methods such as conventional flow cytometry, exploiting the plethora of molecules expressed on their surface. In this review, we summarize the current knowledge about the biology and the composition of MV, as well as their role within the TME. We highlight not only the challenges and potential of MV as novel biomarkers for cancer, but also discuss their possible use for therapeutic intervention.

Ror2 signaling is required for local upregulation of GDF6 and activation of BMP signaling at the neural plate border.

The receptor tyrosine kinase Ror2 is a major Wnt receptor that activates ß-catenin-independent signaling and plays a conserved role in the regulation of convergent extension movements and planar cell polarity in vertebrates. Mutations in the ROR2 gene cause recessive Robinow syndrome in humans, a short-limbed dwarfism associated with craniofacial malformations. Here, we show that Ror2 is required for local upregulation of gdf6 at the neural plate border in Xenopus embryos. Ror2 morphant embryos fail to upregulate neural plate border genes and show defects in the induction of neural crest cell fate. These embryos lack the spatially restricted activation of BMP signaling at the neural plate border at early neurula stages, which is required for neural crest induction. Ror2-dependent planar cell polarity signaling is required in the dorsolateral marginal zone during gastrulation indirectly to upregulate the BMP ligand Gdf6 at the neural plate border and Gdf6 is sufficient to rescue neural plate border specification in Ror2 morphant embryos. Thereby, Ror2 links Wnt/planar cell polarity signaling to BMP signaling in neural plate border specification and neural crest induction.

Interhospital transport of ARDS patients on extracorporeal membrane oxygenation.

Veno-venous extracorporeal membrane oxygenation (ECMO) can be a lifesaving therapy for patients with severe acute respiratory distress syndrome (ARDS). ECMO is a technically complex and challenging procedure and should therefore only be performed in specialized centers. Transporting ARDS patients to ECMO centers for treatment can be dangerous because of the risk of hypoxemia during transport. This raises the question if ECMO should not be already initiated in the transferring hospital before transport. Over a 5-year period, we studied ARDS patients who had been transported to our department by our mobile ECMO team for further treatment after ECMO had already been initiated at the referring hospital. Data for analysis were obtained from our patient data management system (PDMS), the referral documents, and from the referring hospitals. Seventy-five patients meeting the selection criteria were studied. All had been successfully cannulated in the transferring hospitals. They were transported to our ECMO center by helicopter (n = 34) or mobile intensive care units (n = 41). No patient died during transport. Forty four of the patients were transported at night. Twenty-six patients (35%) died in our intensive care unit due to a therapy refractory course, comorbidities or limitation of therapy. Patients on ECMO therapy can be safely transferred to a specialist center. Setting up ECMO in an unfamiliar location and the subsequent patient transport can be very challenging and should only be performed by a highly trained, experienced team.

Cerebral metastases: do size, peritumoral edema, or multiplicity predict infiltration into brain parenchyma?

BACKGROUND: Brain metastases (BMs) are the most frequent malignancy of the central nervous system. Previous research suggested that some metastases show infiltrative behavior rather than sharp demarcation. We hypothesized that three magnetic resonance (MR) imaging parameters-(a) tumor size, (b) extent of peritumoral edema, and (c) presence of multiple BMs-are predictors of cellular invasion beyond the surgically identifiable tumor margins. METHODS: We performed a post hoc analysis on prospectively collected data of patients with BMs. Biopsies beyond the resection margin and immunohistochemistry were performed to assess infiltration status. The three MR imaging parameters were dichotomized into diameters ≤ 30 mm ("small") and > 30 mm ("large"), amount of peritumoral edema "extended" and "limited," and "multiple BMs" and "single BMs," respectively. The association between infiltration status and imaging parameters was calculated using chi-square test. RESULTS: Biopsy beyond the resection margin was performed in 77 patients; 49 (63.6%) had supramarginal infiltration and 28 patients (36.4%) showed no infiltration. Histological evidence of tumor infiltration was found in 25/41 patients with smaller lesions (61%) and in 24/36 with larger lesions (66.7%, p = 0.64), in 28/44 patients with limited (63.6%) and in 21/33 patients with extended edema (63.6%, p = 1.0), in 28/45 patients (62.2%) with single BM and in 21/32 patients (65.6%) with multiple BMs (p = 0.81). CONCLUSIONS: Based on the post hoc analysis of our prospective trial data, we could not confirm the hypothesis that infiltration of brain parenchyma beyond the glial pseudocapsule is associated with the MR imaging parameters tumor size, extent of edema, or multiplicity of metastases.

PI3K: A master regulator of brain metastasis-promoting macrophages/microglia.

Mutations and activation of the PI3K signaling pathway in breast cancer cells have been linked to brain metastases. However, here we describe that in some breast cancer brain metastases samples the protein expression of PI3K signaling components is restricted to the metastatic microenvironment. In contrast to the therapeutic effects of PI3K inhibition on the breast cancer cells, the reaction of the brain microenvironment is less understood. Therefore we aimed to quantify the PI3K pathway activity in breast cancer brain metastasis and investigate the effects of PI3K inhibition on the central nervous system (CNS) microenvironment. First, to systematically quantify the PI3K pathway activity in breast cancer brain metastases, we performed a prospective biomarker study using a reverse phase protein array (RPPA). The majority, namely 30 out of 48 (62.5%) brain metastatic tissues examined, revealed high PI3K signaling activity that was associated with a median overall survival (OS) of 9.41 months, while that of patients, whose brain metastases showed only moderate or low PI3K activity, amounted to only 1.93 and 6.71 months, respectively. Second, we identified PI3K as a master regulator of metastasis-promoting macrophages/microglia during CNS colonization; and treatment with buparlisib (BKM120), a pan-PI3K Class I inhibitor with a good blood-brain-barrier penetrance, reduced their metastasis-promoting features. In conclusion, PI3K signaling is active in the majority of breast cancer brain metastases. Since PI3K inhibition does not only affect the metastatic cells but also re-educates the metastasis-promoting macrophages/microglia, PI3K inhibition may hold considerable promise in the treatment of brain metastasis and the respective microenvironment.

High-frequency oscillatory ventilation guided by transpulmonary pressure in acute respiratory syndrome: an experimental study in pigs.

BACKGROUND: Recent clinical studies have not shown an overall benefit of high-frequency oscillatory ventilation (HFOV), possibly due to injurious or non-individualized HFOV settings. We compared conventional HFOV (HFOVcon) settings with HFOV settings based on mean transpulmonary pressures (PLmean) in an animal model of experimental acute respiratory distress syndrome (ARDS). METHODS: ARDS was induced in eight pigs by intrabronchial installation of hydrochloric acid (0.1 N, pH 1.1; 2.5 ml/kg body weight). The animals were initially ventilated in volume-controlled mode with low tidal volumes (6 ml kg- 1) at three positive end-expiratory pressure (PEEP) levels (5, 10, 20 cmH2O) followed by HFOVcon and then HFOV PLmean each at PEEP 10 and 20. The continuous distending pressure (CDP) during HFOVcon was set at mean airway pressure plus 5 cmH2O. For HFOV PLmean it was set at mean PL plus 5 cmH2O. Baseline measurements were obtained before and after induction of ARDS under volume controlled ventilation with PEEP 5. The same measurements and computer tomography of the thorax were then performed under all ventilatory regimens at PEEP 10 and 20. RESULTS: Cardiac output, stroke volume, mean arterial pressure and intrathoracic blood volume index were significantly higher during HFOV PLmean than during HFOVcon at PEEP 20. Lung density, total lung volume, and normally and poorly aerated lung areas were significantly greater during HFOVcon, while there was less over-aerated lung tissue in HFOV PLmean. The groups did not differ in oxygenation or extravascular lung water index. CONCLUSION: HFOV PLmean is associated with less hemodynamic compromise and less pulmonary overdistension than HFOVcon. Despite the increase in non-ventilated lung areas, oxygenation improved with both regimens. An individualized approach with HFOV settings based on transpulmonary pressure could be a useful ventilatory strategy in patients with ARDS. Providing alveolar stabilization with HFOV while avoiding harmful distending pressures and pulmonary overdistension might be a key in the context of ventilator-induced lung injury.