Macrophage-Associated Mesenchymal Stem Cells Assume an Activated, Migratory, Pro-Inflammatory Phenotype with Increased IL-6 and CXCL10 Secretion

Mesenchymal stem cells (MSCs) exhibit tropism for sites of tissue injury and tumors. However, the influence of the microenvironment on MSC phenotype and localization remains incompletely characterized. In this study, we begin to define a macrophage-induced MSC phenotype. These MSCs secrete interleukin-6 (IL-6), CCL5, and interferon gamma-induced protein-10 (CXCL10) and exhibit increased mobility in response to multiple soluble factors produced by macrophages including IL-8, CCL2, and CCL5. The pro-migratory phenotype is dependent on activation of a c-Jun N-terminal kinase (JNK) pathway. This work begins to identify the influence of macrophages on MSC biology. These interactions are likely to play an important role in the tissue inflammatory response and may provide insight into the migratory potential of MSCs in inflammation and tissue injury

Association of Plasmodium falciparum with Human Endothelial Cells in vitro.

Endothelial abnormalities play a critical role in the pathogenesis of malaria caused by the human pathogen, Plasmodium falciparum. In serious infections and especially in cerebral malaria, red blood cells infected with the parasite are sequestered in small venules in various organs, resulting in endothelial activation and vascular occlusion, which are believed to be largely responsible for the morbidity and mortality caused by this infection, especially in children. We demonstrate that after incubation with infected red blood cells (iRBCs), cultured human umbilical vein endothelial cells (HUVECs) contain parasite protein, genomic DNA, and RNA, as well as intracellular vacuoles with apparent parasite-derived material, but not engulfed or adherent iRBCs. The association of this material with the HUVECs is observed over 96 hours after removal of iRBCs. This phenomenon may occur in endothelial cells in vivo by the process of trogocytosis, in which transfer of material between cells depends on direct cell contact. This process may contribute to the endothelial activation and disruption involved in the pathogenesis of cerebral malaria

Clinical actionability of comprehensive genomic profiling for management of rare or refractory cancers

Background. The frequency with which targeted tumor sequencing results will lead to implemented change in care is unclear. Prospective assessment of the feasibility and limitations of using genomic sequencing is critically important. Methods. A prospective clinical study was conducted on 100 patients with diverse-histology, rare, or poor-prognosis cancers to evaluate the clinical actionability of a Clinical Laboratory Improvement Amendments (CLIA)-certified, comprehensive genomic profiling assay (FoundationOne), using formalin-fixed, paraffin-embedded tumors. The primary objectives were to assess utility, feasibility, and limitations of genomic sequencing for genomically guided therapy or other clinical purpose in the setting of a multidisciplinary molecular tumor board. Results. Of the tumors from the 92 patients with sufficient tissue, 88 (96%) had at least one genomic alteration (average 3.6, range 0–10). Commonly altered pathways included p53 (46%), RAS/RAF/MAPK (rat sarcoma; rapidly accelerated fibrosarcoma; mitogen-activated protein kinase) (45%), receptor tyrosine kinases/ligand (44%), PI3K/AKT/mTOR (phosphatidylinositol-4,5-bisphosphate 3-kinase; protein kinase B; mammalian target of rapamycin) (35%), transcription factors/regulators (31%), and cell cycle regulators (30%). Many low frequency but potentially actionable alterations were identified in diverse histologies. Use of comprehensive profiling led to implementable clinical action in 35% of tumors with genomic alterations, including genomically guided therapy, diagnostic modification, and trigger for germline genetic testing. Conclusion. Use of targeted next-generation sequencing in the setting of an institutional molecular tumor board led to implementable clinical action in more than one third of patients with rare and poor-prognosis cancers. Major barriers to implementation of genomically guided therapy were clinical status of the patient and drug access. Early and serial sequencing in the clinical course and expanded access to genomically guided early-phase clinical trials and targeted agents may increase actionability. Implications for Practice: Identification of key factors that facilitate use of genomic tumor testing results and implementation of genomically guided therapy may lead to enhanced benefit for patients with rare or difficult to treat cancers. Clinical use of a targeted next-generation sequencing assay in the setting of an institutional molecular tumor board led to implementable clinical action in over one third of patients with rare and poor prognosis cancers. The major barriers to implementation of genomically guided therapy were clinical status of the patient and drug access both on trial and off label. Approaches to increase actionability include early and serial sequencing in the clinical course and expanded access to genomically guided early phase clinical trials and targeted agents

Outcomes of Children and Adolescents with Advanced Hereditary Medullary Thyroid Carcinoma Treated with Vandetanib.

Purpose: Vandetanib is well-tolerated in patients with advanced medullary thyroid carcinoma (MTC). Long-term outcomes and mechanisms of MTC progression have not been reported previously.Experimental Design: We monitored toxicities and disease status in patients taking vandetanib for hereditary, advanced MTC. Tumor samples were analyzed for molecular mechanisms of disease progression.Results: Seventeen patients [8 male, age 13 (9-17)* years] enrolled; 16 had a RET p.Met918Thr germline mutation. The duration of vandetanib therapy was 6.1 (0.1-9.7+)* years with treatment ongoing in 9 patients. Best response was partial response in 10, stable disease in 6, and progressive disease in one patient. Duration of response was 7.4 (0.6-8.7+)* and 4.9 (0.6-7.8+)* years in patients with PR and SD, respectively. Six patients died 2.0 (0.4-5.7)* years after progression. Median progression-free survival (PFS) was 6.7 years [95% confidence interval (CI): 2.3 years-undefined] and 5-year overall survival (OS) was 88.2% (95% CI: 60.6%-96.9%). Of 16 patients with a RET p.Met918Thr mutation, progression-free survival was 6.7 years (95% CI: 3.1-undefined) and 5-year overall survival was 93.8% (95% CI: 63.2%-99.1%). No patients terminated treatment because of toxicity. DNA sequencing of tissue samples (n = 11) identified an increase in copy number alterations across the genome as a potential mechanism of drug resistance [*median (range)].Conclusions: This study demonstrates that vandetanib is safe and results in sustained responses in children and adolescents with hereditary MTC. Our preliminary molecular data suggest that an increase in copy number abnormalities may be associated with tumor progression in hereditary MTC patients treated with vandetanib. Clin Cancer Res; 24(4); 753-65. ©2017 AACR

Elevated visual dependency in young adults after chemotherapy in childhood

Chemotherapy in childhood can result in long-term neurophysiological side-effects, which could extend to visual processing, specifically the degree to which a person relies on vision to determine vertical and horizontal (visual dependency). We investigated whether adults treated with chemotherapy in childhood experience elevated visual dependency compared to controls and whether any difference is associated with the age at which subjects were treated. Visual dependency was measured in 23 subjects (mean age 25.3 years) treated in childhood with chemotherapy (CTS) for malignant, solid, non-CNS tumors. We also stratified CTS into two groups: those treated before 12 years of age and those treated from 12 years of age and older. Results were compared to 25 healthy, age-matched controls. The subjective visual horizontal (SVH) and vertical (SVV) orientations was recorded by having subjects position an illuminated rod to their perceived horizontal and vertical with and without a surrounding frame tilted clockwise and counter-clockwise 20° from vertical. There was no significant difference in rod accuracy between any CTS groups and controls without a frame. However, when assessing visual dependency using a frame, CTS in general (p = 0.006) and especially CTS treated before 12 years of age (p = 0.001) tilted the rod significantly further in the direction of the frame compared to controls. Our findings suggest that chemotherapy treatment before 12 years of age is associated with elevated visual dependency compared to controls, implying a visual bias during spatial activities. Clinicians should be aware of symptoms such as visual vertigo in adults treated with chemotherapy in childhood

Access to palliative care for patients with advanced cancer: A longitudinal population analysis

Background The UK National Health Service is striving to improve access to palliative care for patients with advanced cancer however limited information exists on the level of palliative care support currently provided in the UK. We aimed to establish the duration and intensity of palliative care received by patients with advanced cancer and identify which cancer patients are missing out. Methods Retrospective cancer registry, primary care and secondary care data were obtained and linked for 2474 patients who died of cancer between 2010 and 2012 within a large metropolitan UK city. Associations between the type, duration, and amount of palliative care by demographic characteristics, cancer type, and therapies received were assessed using Chi-squared, Mann-Whitney or Kruskal-Wallis tests. Multinomial multivariate logistic regression was used to assess the odds of receiving community and/or hospital palliative care compared to no palliative care by demographic characteristics, cancer type, and therapies received. Results Overall 64.6% of patients received palliative care. The average palliative care input was two contacts over six weeks. Community palliative care was associated with more palliative care events (p<0.001) for a longer duration (p<0.001). Patients were less likely to receive palliative care if they were: male (p = 0.002), aged 80 years or over (p<0.05), diagnosed with lung cancer (p<0.05), had not received an opioid prescription (p<0.001), or had not received chemotherapy (p<0.001). Patients given radiotherapy were more likely to receive community only palliative care compared to no palliative care (Odds Ratio = 1.49, 95% Confidence Interval = 1.16–1.90). Conclusion Timely supportive care for cancer patients is advocated but these results suggest that older patients and those who do not receive anti-cancer treatment or opioid analgesics miss out. These patients should be targeted for assessment to identify unmet needs which could benefit from palliative care input

Variability in school closure decisions in response to 2009 H1N1: a qualitative systems improvement analysis

<p>Abstract</p> <p>Background</p> <p>School closure was employed as a non-pharmaceutical intervention against pandemic 2009 H1N1, particularly during the first wave. More than 700 schools in the United States were closed. However, closure decisions reflected significant variation in rationales, decision triggers, and authority for closure. This variability presents the opportunity for improved efficiency and decision-making.</p> <p>Methods</p> <p>We identified media reports relating to school closure as a response to 2009 H1N1 by monitoring high-profile sources and searching Lexis-Nexis and Google news alerts, and reviewed reports for key themes. News stories were supplemented by observing conference calls and meetings with health department and school officials, and by discussions with decision-makers and community members.</p> <p>Results</p> <p>There was significant variation in the stated goal of closure decision, including limiting community spread of the virus, protecting particularly vulnerable students, and responding to staff shortages or student absenteeism. Because the goal of closure is relevant to its timing, nature, and duration, unclear rationales for closure can challenge its effectiveness. There was also significant variation in the decision-making authority to close schools in different jurisdictions, which, in some instances, was reflected in open disagreement between school and public health officials. Finally, decision-makers did not appear to expect the level of scientific uncertainty encountered early in the pandemic, and they often expressed significant frustration over changing CDC guidance.</p> <p>Conclusions</p> <p>The use of school closure as a public health response to epidemic disease can be improved by ensuring that officials clarify the goals of closure and tailor closure decisions to those goals. Additionally, authority to close schools should be clarified in advance, and decision-makers should expect to encounter uncertainty disease emergencies unfold and plan accordingly.</p

Inflammatory cytokine gene expression by MSCs is affected by macrophage-secreted soluble factors.

<p>MSCs exposed to macrophage CM for 24 hours express an altered inflammatory cytokine gene expression profile. Analysis of 84 key genes mediating the inflammatory response was conducted using RT-PCR generating a heat map expressing log-fold changes. Gray boxes represent genes that were undetected in either the control MSCs or the macrophage CM-stimulated MSCs (A). When stimulated by macrophage CM, MSCs increase the expression of inflammatory factors such as, CCL7, IL-8, CCL20, CXCL6, CCL2, CCL5, CXCL1, and CXCL3. The changes ranged from 2.1 to 12.9-fold (B). These data can also be visualized in a scatter plot, showing gene up-regulation as points scattered into the upper left quadrant (C).</p

Stimulation of mesenchymal stem cells by CCL5, CCL2, and IL-8 secretion induces migration.

<p>To determine the role of macrophage-secreted CCL5, CCL2 (MCP-1), and IL-8 in MSC migration, the level of migration in response to recombinant proteins was analyzed. CCL5 (A), CCL2 (B), and IL-8 (C) significantly increased the number of migratory MSCs in a standard Boyden chamber chemotaxis assay. To further characterize the role of CCL5, CCL2, and IL-8 in macrophage-induced MSC migration, neutralizing antibodies targeting these factors were added to macrophage CM prior to migration. While each individual factor induced MSC migration, only CCL5 inhibition reduced MSC migration in response to macrophage CM (D, E, F).</p

Macrophages induce activation of the c-Jun NH2-terminal kinase pathway in MSCs.

<p>To validate the macrophage-induced activation of the c-Jun NH2-terminal kinase (JNK) signaling pathway in MSCs, protein levels of phosphorylated downstream components were assessed by immunoblotting. Exposure to CM from dU937 macrophages induced activation of JNK1, 2, 3 after 15 minutes (A). An increase in the expression of phospho-c-Jun and decrease in the expression of ATF-2 was observed after a 30-minute treatment with dU937 CM (B). These results suggest that in addition to its control of cellular differentiation, proliferation, and apoptosis, the AP-1 transcription factors may also play a role in cellular chemotaxis (C).</p