Preclinical evidence for employing MEK inhibition in NRAS mutated pediatric gastroenteropancreatic neuroendocrine-like tumors.

BACKGROUND: Pediatric gastroenteropancreatic neuroendocrine tumors are exceedingly rare, resulting in most pediatric treatment recommendations being based on data derived from adults. Trametinib is a kinase inhibitor that targets MEK1/2 and has been employed in the treatment of cancers harboring mutations in the Ras pathway. METHODS: We utilized an established human pediatric gastroenteropancreatic neuroendocrine-like tumor patient-derived xenograft (PDX) with a known NRAS mutation to study the effects of MEK inhibition. We evaluated the effects of trametinib on proliferation, motility, and tumor growth in vivo. We created an intraperitoneal metastatic model of this PDX, characterized both the phenotype and the genotype of the metastatic PDX and again, investigated the effects of MEK inhibition. RESULTS: We found target engagement with decreased ERK1/2 phosphorylation with trametinib treatment. Trametinib led to decreased in vitro cell growth and motility, and decreased tumor growth and increased animal survival in a murine flank tumor model. Finally, we demonstrated that trametinib was able to significantly decrease gastroenteropancreatic neuroendocrine intraperitoneal tumor metastasis. CONCLUSIONS: The results of these studies support the further investigation of MEK inhibition in pediatric NRAS mutated solid tumors.

Comparisons of Sleep, Demographics, and Health-Related Variables in Older Long and Average Duration Sleepers.

Introduction Long sleep duration is associated with many health risks, particularly in older adults, but little is known about other characteristics associated with long sleep duration. Methods Across 5 sites, adults aged 60-80 years who reported sleeping 8-9 h ("long sleepers", n = 95) or 6-7.25 h ("average sleepers", n = 103) were assessed for two weeks using actigraphy and sleep diary. Demographic and clinical characteristics, objective sleep apnea screening, self-reported sleep outcomes, and markers of inflammation and glucose regulation were measured. Results Compared to average sleepers, long sleepers had a greater likelihood of being White and unemployed and/or retired. Long sleepers also reported longer time in bed, total sleep time and wake after sleep onset by sleep diary and by actigraphy. Other measures including medical co-morbidity, apnea/hypopnea index, sleep related outcomes such as sleepiness, fatigue, depressed mood, or markers of inflammation and glucose metabolism did not differ between long and average sleepers. Conclusion Older adults with long sleep duration were more likely to be White, report unemployment and retirement suggesting the social factors or related sleep opportunity contributed to long sleep duration in the sample. Despite known health risks of long sleep duration, neither co-morbidity nor markers of inflammation or metabolism differed in older adults with long sleep duration compared with those with average sleep duration.

Using 3D-bioprinted models to study pediatric neural crest-derived tumors.

The use of three-dimensional (3D) bioprinting has remained at the forefront of tissue engineering and has recently been employed for generating bioprinted solid tumors to be used as cancer models to test therapeutics. In pediatrics, neural crest-derived tumors are the most common type of extracranial solid tumors. There are only a few tumor-specific therapies that directly target these tumors, and the lack of new therapies remains detrimental to improving the outcomes for these patients. The absence of more efficacious therapies for pediatric solid tumors, in general, may be due to the inability of the currently employed preclinical models to recapitulate the solid tumor phenotype. In this study, we utilized 3D bioprinting to generate neural crest-derived solid tumors. The bioprinted tumors consisted of cells from established cell lines and patient-derived xenograft tumors mixed with a 6% gelatin/1% sodium alginate bioink. The viability and morphology of the bioprints were analyzed via bioluminescence and immunohisto chemistry, respectively. We compared the bioprints to traditional twodimensional (2D) cell culture under conditions such as hypoxia and therapeutics. We successfully produced viable neural crest-derived tumors that retained the histology and immunostaining characteristics of the original parent tumors. The bioprinted tumors propagated in culture and grew in orthotopic murine models. Furthermore, compared to cells grown in traditional 2D culture, the bioprinted tumors were resistant to hypoxia and chemotherapeutics, suggesting that the bioprints exhibited a phenotype that is consistent with that seen clinically in solid tumors, thus potentially making this model superior to traditional 2D culture for preclinical investigations. Future applications of this technology entail the potential to rapidly print pediatric solid tumors for use in high-throughput drug studies, expediting the identification of novel, individualized therapies.

The Effects of Protein Phosphatase 2A Activation with Novel Tricyclic Sulfonamides on Hepatoblastoma.

BACKGROUND: The tumor suppressor, protein phosphatase 2A (PP2A), is downregulated in hepatoblastoma. We aimed to examine the effects of two novel compounds of the tricyclic sulfonamide class, ATUX-3364 (3364) and ATUX-8385 (8385), designed to activate PP2A without causing immunosuppression, on human hepatoblastoma. METHODS: An established human hepatoblastoma cell line, HuH6, and a human hepatoblastoma patient-derived xenograft, COA67, were treated with increasing doses of 3364 or 8385, and viability, proliferation, cell cycle and motility were investigated. Cancer cell stemness was evaluated by real-time PCR and tumorsphere forming ability. Effects on tumor growth were examined using a murine model. RESULTS: Treatment with 3364 or 8385 significantly decreased viability, proliferation, cell cycle progression and motility in HuH6 and COA67 cells. Both compounds significantly decreased stemness as demonstrated by decreased abundance of OCT4, NANOG, and SOX2 mRNA. The ability of COA67 to form tumorspheres, another sign of cancer cell stemness, was significantly diminished by 3364 and 8385. Treatment with 3364 resulted in decreased tumor growth in vivo. CONCLUSION: Novel PP2A activators, 3364 and 8385, decreased hepatoblastoma proliferation, viability, and cancer cell stemness in vitro. Animals treated with 3364 had decreased tumor growth. These data provide evidence for further investigation of PP2A activating compounds as hepatoblastoma therapeutics.

PIM Kinase Inhibition Attenuates the Malignant Progression of Metastatic Hepatoblastoma.

Hepatoblastoma is the most common primary pediatric liver tumor. Children with pulmonary metastases at diagnosis experience survival rates as low as 25%. We have shown PIM kinases play a role in hepatoblastoma tumorigenesis. In this study, we assessed the role of PIM kinases in metastatic hepatoblastoma. We employed the metastatic hepatoblastoma cell line, HLM_2. PIM kinase inhibition was attained using PIM3 siRNA and the pan-PIM inhibitor, AZD1208. Effects of PIM inhibition on proliferation were evaluated via growth curve. Flow cytometry determined changes in cell cycle. AlamarBlue assay assessed effects of PIM kinase inhibition and cisplatin treatment on viability. The lethal dose 50% (LD50) of each drug and combination indices (CI) were calculated and isobolograms constructed to determine synergy. PIM kinase inhibition resulted in decreased HLM_2 proliferation, likely through cell cycle arrest mediated by p21. Combination therapy with AZD1208 and cisplatin resulted in synergy, potentially through downregulation of the ataxia-telangiectasia mutated (ATM) kinase DNA damage response pathway. When assessing the combined effects of pharmacologic PIM kinase inhibition with cisplatin on HLM_2 cells, we found the agents to be synergistic, potentially through inhibition of the ATM pathway. These findings support further exploration of PIM kinase inhibition as a therapeutic strategy for metastatic hepatoblastoma.

Pre-Clinical Study Evaluating Novel Protein Phosphatase 2A Activators as Therapeutics for Neuroblastoma.

BACKGROUND: Protein phosphatase 2A (PP2A) functions as an inhibitor of cancer cell proliferation, and its tumor suppressor function is attenuated in many cancers. Previous studies utilized FTY720, an immunomodulating compound known to activate PP2A, and demonstrated a decrease in the malignant phenotype in neuroblastoma. We wished to investigate the effects of two novel PP2A activators, ATUX-792 (792) and DBK-1154 (1154). METHODS: Long-term passage neuroblastoma cell lines and human neuroblastoma patient-derived xenograft (PDX) cells were used. Cells were treated with 792 or 1154, and viability, proliferation, and motility were examined. The effect on tumor growth was investigated using a murine flank tumor model. RESULTS: Treatment with 792 or 1154 resulted in PP2A activation, decreased cell survival, proliferation, and motility in neuroblastoma cells. Immunoblotting revealed a decrease in MYCN protein expression with increasing concentrations of 792 and 1154. Treatment with 792 led to tumor necrosis and decreased tumor growth in vivo. CONCLUSIONS: PP2A activation with 792 or 1154 decreased survival, proliferation, and motility of neuroblastoma in vitro and tumor growth in vivo. Both compounds resulted in decreased expression of the oncogenic protein MYCN. These findings indicate a potential therapeutic role for these novel PP2A activators in neuroblastoma.

Targeting High-Risk Neuroblastoma Patient-Derived Xenografts with Oncolytic Virotherapy.

Cancer is the leading cause of death by disease in children, and over 15% of pediatric cancer-related mortalities are due to neuroblastoma. Current treatment options for neuroblastoma remain suboptimal as they often have significant toxicities, are associated with long-term side effects, and result in disease relapse in over half of children with high-risk disease. There is a dire need for new therapies, and oncolytic viruses may represent an effective solution. Oncolytic viruses attack tumor cells in two ways: direct infection of tumor cells leading to cytolysis, and production of a debris field that stimulates an anti-tumor immune response. Our group has previously shown that M002, an oncolytic herpes simplex virus (oHSV), genetically engineered to express murine interleukin-12 (mIL-12), was effective at targeting and killing long term passage tumor cell lines. In the current study, we investigated M002 in three neuroblastoma patient-derived xenografts (PDXs). PDXs better recapitulate the human condition, and these studies were designed to gather robust data for translation to a clinical trial. We found that all three PDXs expressed viral entry receptors, and that the virus actively replicated in the cells. M002 caused significant tumor cell death in 2D culture and 3D bioprinted tumor models. Finally, the PDXs displayed variable susceptibility to M002, with a more profound effect on high-risk neuroblastoma PDXs compared to low-risk PDX. These findings validate the importance of incorporating PDXs for preclinical testing of oncolytic viral therapeutics and showcase a novel technique, 3D bioprinting, to test therapies in PDXs. Collectively, our data indicate that oHSVs effectively target high-risk neuroblastoma, and support the advancement of this therapy to the clinical setting.

Regional differences in BMI, obesity, and exercise frequency in a large veteran service organization: A secondary analysis of new veteran member surveys from Team Red, White & Blue.

The purpose of the present study was to examine regional differences in average self-reported BMI, obesity prevalence, and frequent exercise (FE) among members of Team Red, White, and Blue (Team RWB) - a military veteran service organization founded to increase physical activity in veterans. A total of 10,015 military veterans participated in a needs assessment conducted by Team RWB between December 2014 and August 2016. Multivariate regression analysis with bootstrapped coefficients revealed that: BMI was highest in the Midwest region (M = 28.282) of the United States, F(20, 9882) = 105.560, p < 0.001; obesity prevalence was highest in the Southcentral (32.300%) and Southeast (32.200%) regions, x2(9731) = 10,850, p < 0.001; and FE was most prevalent in the Mid-Atlantic region (67.3%), x2(9882) = 11,291, p < 0.001.The results of this study closely mirror results found in studies of the general population. A better understanding of the geographic distribution of these outcomes could guide the targeting of sub-populations for public health programs. In particular, Team Red, White & Blue community growth and other fitness based public health programs could be expanded to reach more veterans.

Team Red, White & Blue: a community-based model for harnessing positive social networks to enhance enrichment outcomes in military veterans reintegrating to civilian life.

Military service assimilates individuals into a socially cohesive force to address dangerous and traumatic situations that have no counterpart in civilian life. Upon leaving active duty, many veterans experience a "reverse culture shock" when trying to reintegrate into civilian institutions and cultivate supportive social networks. Poor social reintegration is associated with greater morbidity and premature mortality in part due to adoption of risky health behaviors, social isolation, and inadequate engagement in health care services. Although institutions like the Veterans Health Administration (VA) do much to address the complex psychosocial and health care needs of veterans and their families with evidence-based care, only 61% of Operations Enduring and Iraqi Freedom (OEF/OIF) Veterans are enrolled in VA care and there are numerous perceived barriers to care for enrollees. To address this gap, a community-based nonprofit organization, Team Red, White & Blue (RWB), was created to help veterans establish health-enriching social connections with communities through the consistent provision of inclusive and locally tailored physical, social, and service activities. This article provides an overview of the development and refinement of a theory-based framework for veteran health called the Enrichment Equation, comprised of three core constructs: health, people, and purpose. By operationalizing programming activities and roles, we describe how theoretical components were translated into a social networking implementation package that enabled rapid national spread of Team RWB. We conclude with future opportunities to partner with researchers and other organizations to understand program impact, and to identify effective intervention components that could be adapted for similar vulnerable groups.

Fathering after military deployment: parenting challenges and goals of fathers of young children.

Although often eagerly anticipated, reunification after deployment poses challenges for families, including adjusting to the parent-soldier's return, re-establishing roles and routines, and the potentially necessary accommodation to combat-related injuries or psychological effects. Fourteen male service members, previously deployed to a combat zone, parent to at least one child under seven years of age, were interviewed about their relationships with their young children. Principles of grounded theory guided data analysis to identify key themes related to parenting young children after deployment. Participants reported significant levels of parenting stress and identified specific challenges, including difficulty reconnecting with children, adapting expectations from military to family life, and coparenting. Fathers acknowledged regret about missing an important period in their child's development and indicated a strong desire to improve their parenting skills. They described a need for support in expressing emotions, nurturing, and managing their tempers. Results affirm the need for support to military families during reintegration and demonstrate that military fathers are receptive to opportunities to engage in parenting interventions. Helping fathers understand their children's behavior in the context of age-typical responses to separation and reunion may help them to renew parent-child relationships and reengage in optimal parenting of their young children.

Strong, safe, and secure: negotiating early fathering and military service across the deployment cycle.

Military fathers of young children often endure repeated separations from their children, and these may disrupt the early parent-child relationship. Postdeployment reunification also poses challenges; disruptions that have occurred must often be repaired in the context of heightened emotions on the part of each family member at a time when fathers are themselves readjusting to the routines and responsibilities of family life. The current study employed qualitative research with the central aim of informing a richer understanding of these experiences. Interviews were conducted with 14 military fathers of young children who had experienced separation from their families during deployment. Narratives were coded using principles of grounded theory, and common parenting themes were extracted. Fathers shared their hopes that their young children would develop qualities of strength, confidence, and self-sufficiency. They also discussed difficulty in supporting the development of these qualities in their young children due to problems dealing with the negative emotions and difficult behaviors that their children exhibited. Reliance on their parenting partner was commonly cited as an effective strategy as fathers transitioned back to family life. Implications for intervention programs include the provision of parenting and self-care skills and inclusion of the father's parenting partner in the intervention.

Antibiotic dosing during sustained low-efficiency dialysis: special considerations in adult critically ill patients.

OBJECTIVE: To address issues of antibiotic dosing during sustained low-efficiency dialysis by using available pharmacokinetic data, intermittent and continuous renal replacement therapy dialysis guidelines, and our experience with sustained low-efficiency dialysis. DATA RESOURCES: Published clinical trials, case reports, and reviews of antibiotic dosing in humans during sustained low-efficiency dialysis. DATA EXTRACTION: A search of electronic databases (MEDLINE, PubMed, and Ovid) was conducted by using key words of extended daily dialysis, sustained low-efficiency dialysis, antibiotics, antimicrobial agents, and pharmacokinetics. MEDLINE identified 32 sustained low-efficiency dialysis articles, and PubMed identified 33 articles. All papers describing antibiotic clearance prospectively in patients were considered for this article. DATA SYNTHESIS: We identified nine original research articles and case reports that determined the impact of sustained low-efficiency dialysis on antibiotic clearance in patients. The blood and dialysate flow rates, duration of dialysis, type of filter, and the pharmacokinetic parameters were extracted from each article. If multiple articles on the same drug were published, they were compared for consistency with the aforementioned dialysis parameters and then compared with forms of continuous renal replacement therapy. Antibiotic clearance by sustained low-efficiency dialysis was determined to be similar or higher than continuous renal replacement therapy therapies. The estimated creatinine clearance during sustained low-efficiency dialysis was approximately 60 mL/min to 100 mL/min depending on the blood and dialysate flow rates and the type of filter used. CONCLUSIONS: The potential for significant drug removal during an 8-hr-or-longer sustained low-efficiency dialysis session is evident by the limited number of studies available. Because significant amounts of drug may be removed by sustained low-efficiency dialysis combined with altered pharmacokinetic variables in critically ill patients, the risk for suboptimal drug concentrations and pharmacodynamics must be considered. Appropriate dose and calculation of dosing intervals is essential to provide adequate antibiotic therapy in these patients. It is recommended that institutions who utilize sustained low-efficiency dialysis establish dosing guidelines for all pharmacists and physicians to follow to provide consistent delivery of antibiotics at adequate concentrations.

Racial differences in the prevalence of cardiac sources of embolism in subjects with unexplained stroke or transient ischemic attack evaluated by transesophageal echocardiography.

Little is known about the distribution of cardiac sources of embolism among African-Americans with cryptogenic cerebrovascular events. We compared the prevalence of potential cardiac sources of embolism between black and white patients referred to our laboratory for transesophageal echocardiographic (TEE) evaluation of unexplained stroke or transient ischemic attack. Records were reviewed to exclude subjects with high-risk cardiac or vascular disorders likely to explain the index event. Of 297 patients satisfying the inclusion criteria, 196 were white and 87 black. Potential cardioembolic sources were significantly less common in blacks than in whites (adjusted odds ratio [OR], 0.44; 95% confidence interval [CI] 0.26 to 0.75), and related largely to the difference in prevalence of interatrial communication (OR 0.40; 95% CI 0.21 to 0.74). In contrast, African-Americans had a higher prevalence of left ventricular (LV) hypertrophy (OR 3.50; 95% CI 1.97 to 6.22), and particularly, moderate or severe hypertrophy (OR 4.03; 95% CI 1.88 to 9.65) compared with whites. In conclusion, in African-Americans with unexplained cerebrovascular events, the yield of TEE for potential cardioembolic sources, and especially interatrial communication, is lower than in their white counterparts. African-Americans exhibit a substantially higher prevalence of LV hypertrophy, which may be a marker for a higher burden of subclinical cerebrovascular disease involved in the pathogenesis of cryptogenic cerebral ischemia in this population.