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Exposure to elevated glucocorticoids early in development has been shown to reduce learning ability in vertebrates. We tested the effects of elevated yolk corticosterone (B) and elevated endogenous embryonic B on Japanese quail chick performance in a simple maze. By injecting eggs with a physiologically relevant amount of B prior to incubation we mimicked the elevated yolk B found in eggs of female quail with high plasma B. We also cooled eggs just prior to hatch to induce elevations of the embryos own circulating B. Chicks exposed to high B (B-injected, B-injected and cooled and control-injected and cooled) tended not to fail on first trial as often as control chicks, and chicks from eggs injected with a low dose of B finished the maze significantly faster than controls during their first trial. However, control chicks were significantly faster at maze completion in the second trial than they had been in their first and chicks from other treatment groups were not. This suggests that exposure to high B (either maternal or embryonic) prior to hatch impairs leaning in an avian system. We propose that the seemingly detrimental effects of high B on learning are countered by better ability to solve a novel task, and may be part of a modified behavioral strategy by which an individual can maximize fitness under suboptimal conditions.

Indications for heart-only (HT) versus combined heart-liver transplantation (cHLT) in Fontan patients are still evolving. Current methods to assess liver disease have limitations. At time of transplant, an intra-operative liver inspection done early in the case can allow for a decision to proceed with HT rather than cHLT. We describe the outcomes of Fontan patients listed for cHLT who underwent HT based on direct inspection of the liver at time of transplant. Data are presented as medians (range). Five Fontan patients, ages 15 (11-24) years, were listed for cHLT, including 3 who had worsening liver disease after 11-52 months waiting for HT only. After 112 (2-296) days waiting for cHLT, gross liver inspection via a limited laparotomy at time of transplant did not demonstrate cirrhosis. All patients proceeded with HT only. All donor livers were procured and delivered to back-up recipients. Table 1 shows details of the 5 patients compared to previously published descriptions of HT and cHLT Fontan patients from our center. Post-transplant length of stay was 48 (19-117) days, compared to 26 days for HT and 29 days for cHLT Fontan patients. Prior to discharge, 3 patients were treated for Grade 2R/3A cellular rejection and 1 patient was treated for clinical rejection due to graft dysfunction and arrhythmia without biopsy data. All 5 patients are alive with 19 (9-39) months of post-HT follow-up. Post-transplant liver imaging (by CT in 2 and ultrasound in 3) showed persistent liver disease in 3 patients (heterogeneity ± nodules ± splenomegaly) and worsened findings in 2 patients (increased heterogeneity and splenomegaly, development of new nodules); none have yet demonstrated imaging improvement. Intra-operative gross liver inspection at the time of transplant can result in successful HT in Fontan patients with liver disease. However, continued post-transplant liver evaluation is still needed to determine long-term outcomes. [ABSTRACT FROM AUTHOR]

Patient-tailored silicone plug for HeartMate 3™ left ventricular assist device explantation in two successive males proceeded successfully. Given medical therapeutic advancements, FDA-approved plug systems designed by LVAD manufacturers themselves will be necessary for the near future to provide a safe and simple device explantation alternative that fulfills all regulatory standards., (© 2023. The Author(s).)

Background: The social determinants of health contribute to adverse post-liver transplant outcomes. Identifying unmet social risks may enable transplant teams to improve long-term outcomes for at-risk children. However, providers may feel uncomfortable asking about household-level social risks in the posttransplant period because they might make their patients/families uncomfortable., Methods: We conducted a mixed-methods analysis of caregiver participants (ie, parents/guardians of pediatric liver transplant recipients) in the Social and Contextual Impact on Children Undergoing Liver Transplantation study to assess their perceptions of provider-based social risk screening. Participants (N = 109) completed a 20-min social determinants of health questionnaire that included questions on the acceptability of being asked intimate social risk questions. A subset of participants (N = 37) engaged in an in-depth qualitative interview to share their perceptions of social risk screening., Results: Of 109 participants across 9 US transplant centers, 60% reported financial strain and 30% reported at least 1 material economic hardship (eg, food insecurity, housing instability). Overall, 65% of respondents reported it very or somewhat appropriate and 25% reported being neutral to being screened for social risks in a liver transplant setting. In qualitative analyses, participants reported trust in the providers and a clear understanding of the intention of the screening as prerequisites for liver transplant teams to perform social risk screening., Conclusions: Only a small minority of caregivers found social risk screening unacceptable. Pediatric liver transplant programs should implement routine social risk screening and prioritize the patient and family voices when establishing a screening program to ensure successful implementation., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Activating mutations in GNAQ/GNA11 occur in over 90% of uveal melanomas (UMs), the most lethal melanoma subtype; however, targeting these oncogenes has proven challenging and inhibiting their downstream effectors show limited clinical efficacy. Here, we performed genome-scale CRISPR screens along with computational analyses of cancer dependency and gene expression datasets to identify the inositol-metabolizing phosphatase INPP5A as a selective dependency in GNAQ/11-mutant UM cells in vitro and in vivo. Mutant cells intrinsically produce high levels of the second messenger inositol 1,4,5 trisphosphate (IP3) that accumulate upon suppression of INPP5A, resulting in hyperactivation of IP3-receptor signaling, increased cytosolic calcium and p53-dependent apoptosis. Finally, we show that GNAQ/11-mutant UM cells and patients' tumors exhibit elevated levels of IP4, a biomarker of enhanced IP3 production; these high levels are abolished by GNAQ/11 inhibition and correlate with sensitivity to INPP5A depletion. Our findings uncover INPP5A as a synthetic lethal vulnerability and a potential therapeutic target for GNAQ/11-mutant-driven cancers., (© 2024. The Author(s).)

Background and Aims: Adolescents constitute a unique waitlist cohort that is distinct from younger children. Model for End-stage Liver Disease (MELD) 3.0, which was developed in an adult population of liver transplant candidates, is planned to replace MELD-Sodium in the current liver allocation system for both adults and adolescents aged 12-17. We evaluated the predictive performance of MELD-Sodium, MELD 3.0, and Pediatric End-stage Liver Disease for 90-day waitlist mortality risk among adolescent liver transplant registrants., Approach and Results: New waitlist registrations for primary liver transplants among individuals aged 12-17 and 18-25 for comparison were identified using Organ Procurement and Transplantation Network (OPTN) data from November 17, 2004, to December 31, 2021. The predictive performance of the current and proposed MELD and Pediatric End-stage Liver Disease scores was assessed using Harrell's concordance ( c ) statistic. There were 1238 eligible listings for adolescents aged 12-17 and 1740 young adults aged 18-25. In the adolescent group, 90-day survival was 97.8%, compared with 95.9% in those aged 18-25 (log-rank p = 0.005), with no significant differences when stratified by sex or indication. Among adolescents, increasing MELD 3.0 was associated with an increased hazard of mortality (HR=1.27, 95% CI: 1.18-1.37), and the c -statistic for 90-day waitlist survival using MELD 3.0 was 0.893 compared with 0.871 using MELD-Sodium and 0.852 using Pediatric End-stage Liver Disease., Conclusions: The discriminative ability of MELD 3.0 to rank adolescents according to the risk of death within 90 days was robust. Although MELD 3.0 was initially developed and validated in adults, MELD 3.0 may also improve the prediction of waitlist mortality in adolescents and better represent their urgency for liver transplants., (Copyright © 2023 American Association for the Study of Liver Diseases.)

Aberrant activation of the JAK/STAT pathway is thought to be the critical event in the pathogenesis of the chronic myeloproliferative neoplasms, polycythemia vera, essential thrombocythemia and primary myelofibrosis. The most frequent genetic alteration in these pathologies is the activating JAK2V617F mutation, and expression of the mutant gene in mouse models was shown to cause a phenotype resembling the human diseases. Given the body of genetic evidence, it has come as a sobering finding that JAK inhibitor therapy only modestly suppresses the JAK2V617F allele burden, despite showing clear benefits in terms of reducing splenomegaly and constitutional symptoms in patients. To gain a better understanding if JAK2V617F is required for maintenance of myeloproliferative disease once it has evolved, we generated a conditional inducible transgenic JAK2V617F mouse model using the SCL-tTA-2S tet-off system. Our model corroborates that expression of JAK2V617F in hematopoietic stem and progenitor cells recapitulates key hallmarks of human myeloproliferative neoplasms, and exhibits gender differences in disease manifestation. The disease was found to be transplantable, and importantly, reversible when transgenic JAK2V617F expression was switched off. Our results indicate that mutant JAK2V617F-specific inhibitors should result in profound disease modification by disabling the myeloproliferative clone bearing mutant JAK2., Competing Interests: Some of the authors are full-time employees of Novartis Pharma AG (Emilie A. Chapeau, Emeline Mandon, Vincent Romanet, Nicolas Ebel, Rita Andraos-Rey, Zhiyan Qian, Miltos Kininis, Sabine Zumstein-Mecker, Ralph Tiedt, Francesco Hofmann, Matthias Mueller, Fabienne Baffert), or have been full-time employees of Novartis Pharma AG (Violetta Powajbo, Moriko Ito, Bernd Kinzel, Masato Murakami, Thomas Radimerski). Novartis Pharma AG had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Ruxolitinib is a marketed product of Incyte, for which Novartis Pharma AG received exclusive development and commercialization rights outside of the United States. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Dendritic cell (DC)-based vaccines pulsed with high hydrostatic pressure (HHP)-inactivated tumor cells have been demonstrated to be a promising immunotherapy for solid tumors. We focused on sole injection of tumor cells that were inactivated by HHP and their combination with local radiotherapy (RTx) for in vivo induction of anti-tumor immune responses. HHP-treatment of tumor cells resulted in pre-dominantly necrotic cells with degraded DNA. We confirmed that treatments at 200 MPa or higher completely inhibited the formation of tumor cell colonies in vitro . No tumor growth was seen in vivo after injection of HHP-treated tumor cells. Single vaccination with HHP-killed tumor cells combined with local RTx significantly retarded tumor growth and improved the survival as shown in B16-F10 and CT26 tumor models. In B16-F10 tumors that were irradiated with 2 × 5Gy and vaccinated once with HHP-killed tumor cells, the amount of natural killer (NK) cells, monocytes/macrophages, CD4+ T cells and NKT cells was significantly increased, while the amount of B cells was significantly decreased. In both models, a trend of increased CD8+ T cell infiltration was observed. Generally, in irradiated tumors high amounts of CD4+ and CD8+ T cells expressing PD-1 were found. We conclude that HHP generates inactivated tumor cells that can be used as a tumor vaccine. Moreover, we show for the first time that tumor cell-based vaccine acts synergistically with RTx to significantly retard tumor growth by generating a favorable anti-tumor immune microenvironment.

Like classical chemotherapy regimens used to treat cancer, targeted therapies will also rely upon polypharmacology, but tools are still lacking to predict which combinations of molecularly targeted drugs may be most efficacious. In this study, we used image-based proliferation and apoptosis assays in colorectal cancer cell lines to systematically investigate the efficacy of combinations of two to six drugs that target critical oncogenic pathways. Drug pairs targeting key signaling pathways resulted in synergies across a broad spectrum of genetic backgrounds but often yielded only cytostatic responses. Enhanced cytotoxicity was observed when additional processes including apoptosis and cell cycle were targeted as part of the combination. In some cases, where cell lines were resistant to paired and tripled drugs, increased expression of antiapoptotic proteins was observed, requiring a fourth-order combination to induce cytotoxicity. Our results illustrate how high-order drug combinations are needed to kill drug-resistant cancer cells, and they also show how systematic drug combination screening together with a molecular understanding of drug responses may help define optimal cocktails to overcome aggressive cancers. Cancer Res; 76(23); 6950-63. ©2016 AACR., (©2016 American Association for Cancer Research.)

Profiling candidate therapeutics with limited cancer models during preclinical development hinders predictions of clinical efficacy and identifying factors that underlie heterogeneous patient responses for patient-selection strategies. We established ∼1,000 patient-derived tumor xenograft models (PDXs) with a diverse set of driver mutations. With these PDXs, we performed in vivo compound screens using a 1 × 1 × 1 experimental design (PDX clinical trial or PCT) to assess the population responses to 62 treatments across six indications. We demonstrate both the reproducibility and the clinical translatability of this approach by identifying associations between a genotype and drug response, and established mechanisms of resistance. In addition, our results suggest that PCTs may represent a more accurate approach than cell line models for assessing the clinical potential of some therapeutic modalities. We therefore propose that this experimental paradigm could potentially improve preclinical evaluation of treatment modalities and enhance our ability to predict clinical trial responses.

A variety of cancers depend on JAK2 signaling, including the high-risk subset of B cell acute lymphoblastic leukemias (B-ALLs) with CRLF2 rearrangements. Type I JAK2 inhibitors induce paradoxical JAK2 hyperphosphorylation in these leukemias and have limited activity. To improve the efficacy of JAK2 inhibition in B-ALL, we developed the type II inhibitor CHZ868, which stabilizes JAK2 in an inactive conformation. CHZ868 potently suppressed the growth of CRLF2-rearranged human B-ALL cells, abrogated JAK2 signaling, and improved survival in mice with human or murine B-ALL. CHZ868 and dexamethasone synergistically induced apoptosis in JAK2-dependent B-ALLs and further improved in vivo survival compared to CHZ868 alone. These data support the testing of type II JAK2 inhibition in patients with JAK2-dependent leukemias and other disorders., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Although clinically tested JAK inhibitors reduce splenomegaly and systemic symptoms, molecular responses are not observed in most myeloproliferative neoplasm (MPN) patients. We previously demonstrated that MPN cells become persistent to type I JAK inhibitors that bind the active conformation of JAK2. We investigated whether CHZ868, a type II JAK inhibitor, would demonstrate activity in JAK inhibitor persistent cells, murine MPN models, and MPN patient samples. JAK2 and MPL mutant cell lines were sensitive to CHZ868, including type I JAK inhibitor persistent cells. CHZ868 showed significant activity in murine MPN models and induced reductions in mutant allele burden not observed with type I JAK inhibitors. These data demonstrate that type II JAK inhibition is a viable therapeutic approach for MPN patients., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Purpose: The myeloproliferative neoplasm myelofibrosis is characterized by frequent deregulation of Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling, and JAK inhibitors were shown to reduce splenomegaly and ameliorate disease-related symptoms. However, the mutant clone and bone marrow fibrosis persist in the majority of patients. Using preclinical models, we explored whether JAK and pan-deacetylase inhibitor combination yielded additional benefits., Experimental Design: The combination of the JAK1/2 inhibitor ruxolitinib and panobinostat was investigated using two different mouse models of JAK2(V617F)-driven disease. A Ba/F3 JAK2(V617F) cell-driven leukemic disease model was used to identify tolerated and efficacious doses. The drugs were then evaluated alone and in combination in a mouse model of myeloproliferative neoplasm-like disease based on transplantation of bone marrow transduced with a retrovirus expressing JAK2(V617F). Exposures were determined in blood and tissues, and phosphorylated STAT5 and acetylated histone H3 pharmacodynamic readouts were assessed in spleen and bone marrow. Histologic analysis was conducted on spleen and bone marrow, including staining of reticulin fibers in the latter organ., Results: The combination of ruxolitinib and panobinostat was found to have a more profound effect on splenomegaly, as well as on bone marrow and spleen histology, compared with either agent alone, and the analysis of pharmacodynamic readouts showed that ruxolitinib and panobinostat have nonoverlapping and complementary effects., Conclusion: Combining JAK1/2 and pan-deacetylase inhibitors was fairly well tolerated and resulted in improved efficacy in mouse models of JAK2(V617F)-driven disease compared with the single agents. Thus, the combination of ruxolitinib and panobinostat may represent a promising novel therapeutic modality for myeloproliferative neoplasms., (©2013 AACR.)

PLGA nanoparticles (NPs) are largely developed for biological applications but little is known about their uptake. Therefore, we focused our study on the modalities of insulin-loaded PLGA NPs transport across Caco-2 monolayers, and their hypoglycaemic effect on diabetic rats. Insulin-loaded PLGA NPs were formulated by a double emulsion solvent evaporation process. NPs mean diameter was between 130 and 180 nm. NPs were smooth and spherical with an entrapment efficiency above 80%. Fluorescently labeled NPs were incubated with Caco-2 cells to study the process of uptake and the intracellular fate by flow cytometry and confocal laser scanning microscopy. The kinetic of absorption was time-dependent and occurred by clathrin-mediated endocytosis. The intracellular traffic led to a basolateral exocytosis of NPs. In vitro studies and in vivo intraduodenal administration to diabetic rats showed that NPs were resistant in intestinal conditions long enough to allow both the intestinal absorption of NPs and the delivery of functional insulin in bloodstream. The resulting in vivo hypoglycaemic effect was similar to a long-acting insulin one. As no effect on glycaemia occurred after oral administration, further studies need to be conducted to protect NPs from the degradation occurring at the enteric level., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Multimodal approaches are nowadays successfully applied in cancer therapy. Primary locally acting therapies such as radiotherapy (RT) and surgery are combined with systemic administration of chemotherapeutics. Nevertheless, the therapy of cancer is still a big challenge in medicine. The treatments often fail to induce long-lasting anti-tumor responses. Tumor recurrences and metastases result. Immunotherapies are therefore ideal adjuncts to standard tumor therapies since they aim to activate the patient's immune system against malignant cells even outside the primary treatment areas (abscopal effects). Especially cancer vaccines may have the potential both to train the immune system against cancer cells and to generate an immunological memory, resulting in long-lasting anti-tumor effects. However, despite promising results in phase I and II studies, most of the concepts finally failed. There are some critical aspects in development and application of cancer vaccines that may decide on their efficiency. The time point and frequency of medication, usage of an adequate immune adjuvant, the vaccine's immunogenic potential, and the tumor burden of the patient are crucial. Whole tumor cell vaccines have advantages compared to peptide-based ones since a variety of tumor antigens (TAs) are present. The master requirements of cell-based, therapeutic tumor vaccines are the complete inactivation of the tumor cells and the increase of their immunogenicity. Since the latter is highly connected with the cell death modality, the inactivation procedure of the tumor cell material may significantly influence the vaccine's efficiency. We therefore also introduce high hydrostatic pressure (HHP) as an innovative inactivation technology for tumor cell-based vaccines and outline that HHP efficiently inactivates tumor cells by enhancing their immunogenicity. Finally studies are presented proving that anti-tumor immune responses can be triggered by combining RT with selected immune therapies.

Enzymatic inhibitors of Janus kinase 2 (JAK2) are in clinical development for the treatment of myeloproliferative neoplasms (MPNs), B cell acute lymphoblastic leukemia (B-ALL) with rearrangements of the cytokine receptor subunit cytokine receptor-like factor 2 (CRLF2), and other tumors with constitutive JAK2 signaling. In this study, we identify G935R, Y931C, and E864K mutations within the JAK2 kinase domain that confer resistance across a panel of JAK inhibitors, whether present in cis with JAK2 V617F (observed in MPNs) or JAK2 R683G (observed in B-ALL). G935R, Y931C, and E864K do not reduce the sensitivity of JAK2-dependent cells to inhibitors of heat shock protein 90 (HSP90), which promote the degradation of both wild-type and mutant JAK2. HSP90 inhibitors were 100-1,000-fold more potent against CRLF2-rearranged B-ALL cells, which correlated with JAK2 degradation and more extensive blockade of JAK2/STAT5, MAP kinase, and AKT signaling. In addition, the HSP90 inhibitor AUY922 prolonged survival of mice xenografted with primary human CRLF2-rearranged B-ALL further than an enzymatic JAK2 inhibitor. Thus, HSP90 is a promising therapeutic target in JAK2-driven cancers, including those with genetic resistance to JAK enzymatic inhibitors.

The research on high hydrostatic pressure in medicine and life sciences is multifaceted. According to the used pressure head the research has to be divided into two different parts. To study physiological aspects of pressure on eukaryotic cells physiological pressure (pHHP; < 100 MPa) is used. pHHP induces morphological alterations in the cellular organelles and evokes a reversible stress response similar to the well known heat shock response. pHHP induces highly reversible alterations and normally does not affect cellular viability. The treatment of eukaryotic cells with non-physiological pressure (HHP; > or = 100 MPa) reveals different outcomes. Treatment with HHP < 150 MPa does not markedly affect viability of human cells, but induces apoptosis in murine cells. In human cells apoptosis is observed after treatment with > or = 200 MPa. Moreover, HHP treatment with > 300 MPa leads to necrosis. Therefore, HHP plays a role for the sterilisation of human transplants, of food stuff, and pharmaceuticals. Human tumour cells subjected to HHP > 300 MPa display a necrotic phenotype along with a gelificated cytoplasm, preserve their shape, and retain their immunogenicity. These observations favour the use of HHP to produce whole cell based tumour vaccines. Further experiments revealed that the increment of pressure as well as the pressure holding time influences the cell death of tumour cells. We conclude that high hydrostatic pressure offers both, an economic, easy to apply, clean, and fast technique for the generation of vaccines, and a promising tool to study physiological aspects.