The anticancer drug Dp44mT inhibits T-cell activation and CD25 through a copper-dependent mechanism.

The di-2-pyridylketone thiosemicarbazone Dp44mT is a metal-chelating compound that has been demonstrated to have potent activity as an anticancer agent. Here we report that it also has a dramatic inhibitory effect on T-cell activation in vitro. We found that 10 nM Dp44mT (IC(50) 3.2 nM) prevented the up-regulation of surface CD25, and completely suppressed the activation and proliferation of splenic T cells isolated from Mus musculus that were stimulated with either T-cell receptor (TCR) cross-linking antibodies or phorbol ester plus ionomycin. In contrast, Dp44mT had no adverse effects on the survival of resting T cells. In addition, T cells stimulated in the presence of Dp44mT maintained the ability to up-regulate CD69 surface expression and secrete interleukin-2. Consistent with these observations, Dp44mT did not inhibit multiple canonical signals downstream of the TCR, including the nuclear factor of activated T cells. The effects of Dp44mT were easily mitigated by addition of nontoxic copper chelators or N-acetylcysteine, indicating a role for copper and reactive oxygen species in its actions. Together, these findings suggest that Dp44mT may serve as a potent immunosuppressive agent that could complicate its use as a cancer therapeutic agent, but might have utility in the treatment of autoimmunity.

Essential role for CAML in follicular B cell survival and homeostasis.

Calcium-modulating cyclophilin ligand (CAML) is a ubiquitously expressed protein that is important during thymopoiesis. However, whether it serves a function in mature lymphocytes is unknown. In this article, we show that CAML is essential for survival of peripheral follicular (Fo) B cells. Conditional deletion of CAML in CD19-Cre transgenic mice caused a significant reduction in Fo cell numbers and increased rates of homeostatic proliferation. CAML-deficient Fo cells showed increased cellular turnover and normal proliferative ability. Although CAML-deficient Fo cells responded to AgR stimulation and to B cell activating factor, they displayed decreased survival and increased apoptosis following stimulation with LPS and IL-4 in vitro. Failure to survive was not due to aberrant B cell development in the absence of CAML, because induced deletion of the gene in mature cells resulted in a similar phenotype. These data establish an essential and ongoing role for CAML in the long-term survival of mature B cells.

Effect of clinical decision support for severe hypercholesterolemia on low-density lipoprotein cholesterol levels.

Severe hypercholesterolemia/possible familial hypercholesterolemia (FH) is relatively common but underdiagnosed and undertreated. We investigated whether implementing clinical decision support (CDS) was associated with lower low-density lipoprotein cholesterol (LDL-C) in patients with severe hypercholesterolemia/possible FH (LDL-C ≥ 190 mg/dL). As part of a pre-post implementation study, a CDS alert was deployed in the electronic health record (EHR) in a large health system comprising 3 main sites, 16 hospitals and 53 clinics. Data were collected for 3 months before ('silent mode') and after ('active mode') its implementation. Clinicians were only able to view the alert in the EHR during active mode. We matched individuals 1:1 in both modes, based on age, sex, and baseline lipid lowering therapy (LLT). The primary outcome was difference in LDL-C between the two groups and the secondary outcome was initiation/intensification of LLT after alert trigger. We identified 800 matched patients in each mode (mean ± SD age 56.1 ± 11.8 y vs. 55.9 ± 11.8 y; 36.0% male in both groups; mean ± SD initial LDL-C 211.3 ± 27.4 mg/dL vs. 209.8 ± 23.9 mg/dL; 11.2% on LLT at baseline in each group). LDL-C levels were 6.6 mg/dL lower (95% CI, -10.7 to -2.5; P = 0.002) in active vs. silent mode. The odds of high-intensity statin use (OR, 1.78; 95% CI, 1.41-2.23; P < 0.001) and LLT initiation/intensification (OR, 1.30, 95% CI, 1.06-1.58, P = 0.01) were higher in active vs. silent mode. Implementation of a CDS was associated with lowering of LDL-C levels in patients with severe hypercholesterolemia/possible FH, likely due to higher rates of clinician led LLT initiation/intensification.

Clinician Perspectives on Clinical Decision Support for Familial Hypercholesterolemia.

Familial Hypercholesterolemia (FH) is underdiagnosed in the United States. Clinical decision support (CDS) could increase FH detection once implemented in clinical workflows. We deployed CDS for FH at an academic medical center and sought clinician insights using an implementation survey. In November 2020, the FH CDS was deployed in the electronic health record at all Mayo Clinic sites in two formats: a best practice advisory (BPA) and an in-basket alert. Over three months, 104 clinicians participated in the survey (response rate 11.1%). Most clinicians (81%) agreed that CDS implementation was a good option for identifying FH patients; 78% recognized the importance of implementing the tool in practice, and 72% agreed it would improve early diagnosis of FH. In comparing the two alert formats, clinicians found the in-basket alert more acceptable (p = 0.036) and more feasible (p = 0.042) than the BPA. Overall, clinicians favored implementing the FH CDS in clinical practice and provided feedback that led to iterative refinement of the tool. Such a tool can potentially increase FH detection and optimize patient management.

Evaluation of the portability of computable phenotypes with natural language processing in the eMERGE network.

The electronic Medical Records and Genomics (eMERGE) Network assessed the feasibility of deploying portable phenotype rule-based algorithms with natural language processing (NLP) components added to improve performance of existing algorithms using electronic health records (EHRs). Based on scientific merit and predicted difficulty, eMERGE selected six existing phenotypes to enhance with NLP. We assessed performance, portability, and ease of use. We summarized lessons learned by: (1) challenges; (2) best practices to address challenges based on existing evidence and/or eMERGE experience; and (3) opportunities for future research. Adding NLP resulted in improved, or the same, precision and/or recall for all but one algorithm. Portability, phenotyping workflow/process, and technology were major themes. With NLP, development and validation took longer. Besides portability of NLP technology and algorithm replicability, factors to ensure success include privacy protection, technical infrastructure setup, intellectual property agreement, and efficient communication. Workflow improvements can improve communication and reduce implementation time. NLP performance varied mainly due to clinical document heterogeneity; therefore, we suggest using semi-structured notes, comprehensive documentation, and customization options. NLP portability is possible with improved phenotype algorithm performance, but careful planning and architecture of the algorithms is essential to support local customizations.

Web-Based Tool (FH Family Share) to Increase Uptake of Cascade Testing for Familial Hypercholesterolemia: Development and Evaluation.

BACKGROUND: Familial hypercholesterolemia, a prevalent genetic disorder, remains significantly underdiagnosed in the United States. Cascade testing, wherein individuals diagnosed with familial hypercholesterolemia- probands-contact their family members to inform them of their risk for familial hypercholesterolemia, has low uptake in the United States. Digital tools are needed to facilitate communication between familial hypercholesterolemia probands and their family members and to promote sharing of familial hypercholesterolemia-related risk information. OBJECTIVE: We aimed to create and evaluate a web-based tool designed to enhance familial communication and promote cascade testing for familial hypercholesterolemia. METHODS: A hybrid type 1 implementation science framework and a user-centered design process were used to develop an interactive web-based tool-FH Family Share-that enables familial hypercholesterolemia probands to communicate information about their familial hypercholesterolemia diagnosis with at-risk relatives. Probands can also use the tool to draw a family pedigree and learn more about familial hypercholesterolemia through education modules and curated knowledge resources. Usability guidelines and standards were taken into account during the design and development of the tool. The initial prototype underwent a cognitive walkthrough, which was followed by usability testing with key stakeholders including genetic counselors and patients with familial hypercholesterolemia. Participants navigated the prototype using the think-aloud technique, and their feedback was used to refine features of the tool. RESULTS: Key themes that emerged from the cognitive walkthrough were design, format, navigation, terminology, instructions, and learnability. Expert feedback from the cognitive walkthrough resulted in a rebuild of the web-based tool to align it with institutional standards. Usability testing with genetic counselors and patients with familial hypercholesterolemia provided insights on user experience, satisfaction and interface design and highlighted specific modifications that were made to refine the features of FH Family Share. Genetic counselors and patients with familial hypercholesterolemia suggested inclusion of the following features in the web-based tool: (1) a letter-to-family-member email template, (2) education modules, and (3) knowledge resources. Surveys revealed that 6 of 9 (67%) genetic counselors found information within FH Family Share very easy to find, and 5 of 9 (56%) genetic counselors found information very easy to understand; 5 of 9 (56%) patients found information very easy to find within the website, and 7 of 9 (78%) patients found information very easy to understand. All genetic counselors and patients indicated that FH Family Share was a resource worth returning to. CONCLUSIONS: FH Family Share facilitates communication between probands and their relatives. Once informed, at-risk family members have the option to seek testing and treatment for familial hypercholesterolemia.

Phase I trial of sargramostim/pelareorep therapy in pediatric patients with recurrent or refractory high-grade brain tumors.

Background: Brain tumors are the leading cause of cancer death for pediatric patients. Pelareorep, an immunomodulatory oncolytic reovirus, has intravenous efficacy in preclinical glioma models when preconditioned with GM-CSF (sargramostim). We report a phase I trial with the primary goal of evaluating the safety of sargramostim/pelareorep in pediatric patients with recurrent or refractory high-grade brain tumors and a secondary goal of characterizing immunologic responses. Methods: The trial was open to pediatric patients with recurrent or refractory high-grade brain tumors (3 + 3 cohort design). Each cycle included 3 days of subcutaneous sargramostim followed by 2 days of intravenous pelareorep. Laboratory studies and imaging were acquired upon recruitment and periodically thereafter. Results: Six patients participated, including three glioblastoma, two diffuse intrinsic pontine glioma, and one medulloblastoma. Two pelareorep dose levels of 3 × 108 and 5 × 108 tissue culture infectious dose 50 (TCID50) were assessed. One patient experienced a dose limiting toxicity of persistent hyponatremia. Common low-grade (1 or 2) adverse events included transient fatigue, hypocalcemia, fever, flu-like symptoms, thrombocytopenia, and leukopenia. High-grade (3 or 4) adverse events included neutropenia, lymphopenia, leukopenia, hypophosphatemia, depressed level of consciousness, and confusion. All patients progressed on therapy after a median of 32.5 days and died a median of 108 days after recruitment. Imaging at progression did not show evidence of pseudoprogression or inflammation. Correlative assays revealed transient but consistent changes in immune cells across patients. Conclusions: Sargramostim/pelareorep was administered to pediatric patients with recurrent or refractory high-grade brain tumors. Hyponatremia was the only dose limiting toxicity (DLT), though maximum tolerated dose (MTD) was not determined.

Deploying Clinical Decision Support for Familial Hypercholesterolemia.

Objective: Familial hypercholesterolemia (FH), a prevalent genomic disorder that increases risk of coronary heart disease, remains significantly underdiagnosed. Clinical decision support (CDS) tools have the potential to increase FH detection. We describe our experience in the development and implementation of a genomic CDS for FH at a large academic medical center. Methods: CDS development and implementation were conducted in four phases: (1) development and validation of an algorithm to identify "possible FH"; (2) obtaining approvals from institutional committees to develop the CDS; (3) development of the initial prototype; and (4) use of an implementation science framework to evaluate the CDS. Results: The timeline for this work was approximately 4 years; algorithm development and validation occurred from August 2018 to February 2020. During this 4-year period, we engaged with 15 stakeholder groups to build and integrate the CDS, including health care providers who gave feedback at each stage of development. During CDS implementation six main challenges were identified: (1) need for multiple institutional committee approvals; (2) need to align the CDS with institutional knowledge resources; (3) need to adapt the CDS to differing workflows; (4) lack of institutional guidelines for CDS implementation; (5) transition to a new institutional electronic health record (EHR) system; and (6) limitations of the EHR related to genomic medicine. Conclusion: We identified multiple challenges in different domains while developing CDS for FH and integrating it with the EHR. The lessons learned herein may be helpful in streamlining the development and deployment of CDS to facilitate genomic medicine implementation.

An Implementation Science Framework to Develop a Clinical Decision Support Tool for Familial Hypercholesterolemia.

Electronic health record (EHR)-based clinical decision support (CDS) can address the low awareness and undertreatment of familial hypercholesterolemia (FH), a disorder associated with a markedly increased risk of coronary heart disease. We aimed to incorporate provider perspectives into the development and implementation of a CDS tool for FH. An implementation science framework and a user-centered design process were used to create a CDS tool for FH. Primary care physicians and specialist physicians participated in qualitative interviews, usability testing and an implementation survey. The CDS was configured in two formats-a best practice alert (BPA) and an in-basket message and subsequently deployed in the EHR in silent mode. The key themes that emerged from the analysis of interview transcripts included understanding and awareness of FH, clinical workflow, physician preferences and value of CDS tools, perspectives on patient needs and values and dissemination and implementation. Recommendations related to usability included preferred CDS format and placement, content, timing and frequency, and level of alert urgency/prioritization. In response to the survey, 84.6% of physicians agreed that the CDS would improve early FH diagnosis and 92.3% agreed that it would help them identify and manage FH patients. Physician feedback led to iterative CDS refinement. In summary, we developed a CDS tool for FH using an implementation science framework and physician feedback. Initial deployment revealed a significant burden of FH and the potential for the CDS tool to have a large impact.

Cyclophilins A and B oppositely regulate renal tubular epithelial cell phenotype.

Restoration of kidney tubular epithelium following sublethal injury sequentially involves partial epithelial-mesenchymal transition (pEMT), proliferation, and further redifferentiation into specialized tubule epithelial cells (TECs). Because the immunosuppressant cyclosporine-A produces pEMT in TECs and inhibits the peptidyl-prolyl isomerase (PPIase) activity of cyclophilin (Cyp) proteins, we hypothesized that cyclophilins could regulate TEC phenotype. Here we demonstrate that in cultured TECs, CypA silencing triggers loss of epithelial features and enhances transforming growth factor ß (TGFß)-induced EMT in association with upregulation of epithelial repressors Slug and Snail. This pro-epithelial action of CypA relies on its PPIase activity. By contrast, CypB emerges as an epithelial repressor, because CypB silencing promotes epithelial differentiation, prevents TGFß-induced EMT, and induces tubular structures in 3D cultures. In addition, in the kidneys of CypB knockout mice subjected to unilateral ureteral obstruction, inflammatory and pro-fibrotic events were attenuated. CypB silencing/knockout leads to Slug, but not Snail, downregulation. CypB support of Slug expression depends on its endoplasmic reticulum location, where it interacts with calreticulin, a calcium-buffering chaperone related to Slug expression. As CypB silencing reduces ionomycin-induced calcium release and Slug upregulation, we suggest that Slug expression may rely on CypB modulation of calreticulin-dependent calcium signaling. In conclusion, this work uncovers new roles for CypA and CypB in modulating TEC plasticity and identifies CypB as a druggable target potentially relevant in promoting kidney repair.

Protein synthesis inhibition enhances paraptotic death induced by inhibition of cyclophilins in glioblastoma cells.

Treatment of cancer is frequently unsuccessful related to the loss of apoptotic signaling in malignant cells. This is a particular problem for high-grade gliomas, such as Glioblastoma Multiforme (GBM), which are almost universally fatal within a year or so of diagnosis. Novel therapies that capitalize on non-apoptotic cell death pathways may yield more effective outcomes, if their underlying mechanisms can be more completely deciphered. In a recent publication (ref 10), the mechanisms by which cellular cyclophilins support GBM cell survival have been identified. Inhibition of cyclophilins activated paraptosis, which relied on a combination of endoplasmic reticulum (ER) stress and transient activation of autophagy. An important aspect of this effect was the relative rates of cap-dependent versus cap-independent protein synthesis, which were differentially modulated by protein synthesis inhibitors or mTOR inhibition. Although cycloheximide has previously been characterized as an inhibitor of paraptosis, in the case of cyclophilin inhibition, it appears to significantly enhance stress-related paraptosis and cell death. This work reveals an important role for cap-independent protein translation and autophagy in the ability of GBM cells to resist non-apoptotic death, and adds to our understanding of the events that underlie paraptosis.

Cycloheximide promotes paraptosis induced by inhibition of cyclophilins in glioblastoma multiforme.

Cancer is the second leading cause of death worldwide. Current treatment strategies based on multi-agent chemotherapy and/or radiation regimens have improved overall survival in some cases. However, resistance to apoptosis often develops in cancer cells, and its occurrence is thought to contribute to treatment failure. Non-apoptotic cell death mechanisms have become of great interest, therefore, in hopes that they would bypass tumor cell resistance. Glioblastoma multiforme (GBM), a grade IV astrocytic tumor is the most frequent brain tumor in adults, and has a high rate of mortality. We report that NIM811, a small molecule cyclophilin-binding inhibitor, induces catastrophic vacuolization and cell death in GBM cells. These unique features are distinct from many known cell death pathways, and are associated with an incompletely defined cell death mechanism known as paraptosis. We found that NIM811-induced paraptosis is due to unresolved ER stress. The abnormal upregulation of protein translation was responsible for the build-up of misfolded or unfolded proteins in ER, whereas pro-survival autophagy and UPR signals were shutdown during prolonged treatment with NIM811. Although cycloheximide has been claimed to suppress paraptosis, instead we find that it only temporarily delayed vacuole formation, but actually enhanced paraptotic cell death in the long term. On the other hand, mTOR inhibitors rescued cells from NIM811-induced paraptosis by sustaining autophagy and the UPR, while specifically restraining cap-dependent translation. These findings not only provide new insights into the mechanisms underlying paraptosis, but also shed light on a potential approach to enhance GBM treatment.

ATOH1 Promotes Leptomeningeal Dissemination and Metastasis of Sonic Hedgehog Subgroup Medulloblastomas.

Medulloblastoma arising from the cerebellum is the most common pediatric brain malignancy, with leptomeningeal metastases often present at diagnosis and recurrence associated with poor clinical outcome. In this study, we used mouse medulloblastoma models to explore the relationship of tumor pathophysiology and dysregulated expression of the NOTCH pathway transcription factor ATOH1, which is present in aggressive medulloblastoma subtypes driven by aberrant Sonic Hedgehog/Patched (SHH/PTCH) signaling. In experiments with conditional ATOH1 mouse mutants crossed to Ptch1+/- mice, which develop SHH-driven medulloblastoma, animals with Atoh1 transgene expression developed highly penetrant medulloblastoma at a young age with extensive leptomeningeal disease and metastasis to the spinal cord and brain, resembling xenografts of human SHH medulloblastoma. Metastatic tumors retained abnormal SHH signaling like tumor xenografts. Conversely, ATOH1 expression was detected consistently in recurrent and metastatic SHH medulloblastoma. Chromatin immunoprecipitation sequencing and gene expression profiling identified candidate ATOH1 targets in tumor cells involved in development and tumorigenesis. Among these targets specific to metastatic tumors, there was an enrichment in those implicated in extracellular matrix remodeling activity, cytoskeletal network and interaction with microenvironment, indicating a shift in transcriptomic and epigenomic landscapes during metastasis. Treatment with bone morphogenetic protein or SHH pathway inhibitors decreased tumor cell proliferation and suppressed metastatic tumor growth, respectively. Our work reveals a dynamic ATOH1-driven molecular cascade underlying medulloblastoma metastasis that offers possible therapeutic opportunities. Cancer Res; 77(14); 3766-77. ©2017 AACR.

Inhibition of RAS-mediated transformation and tumorigenesis by targeting the downstream E3 ubiquitin ligase seven in absentia homologue.

Constitutively active RAS small GTPases promote the genesis of human cancers. An important goal in cancer biology is to identify means of countervailing activated RAS signaling to reverse malignant transformation. Oncogenic K-RAS mutations are found in virtually all pancreatic adenocarcinomas, making the RAS pathway an ideal target for therapeutic intervention. How to best contravene hyperactivated RAS signaling has remained elusive in human pancreatic cancers. Guided by the Drosophila studies, we reasoned that a downstream mediator of RAS signals might be a suitable anti-RAS target. The E3 ubiquitin ligase seven in absentia (SINA) is an essential downstream component of the Drosophila RAS signal transduction pathway. Thus, we determined the roles of the conserved human homologues of SINA, SIAHs, in mammalian RAS signaling and RAS-mediated tumorigenesis. We report that similar to its Drosophila counterpart, human SIAH is also required for oncogenic RAS signaling in pancreatic cancer. Inhibiting SIAH-dependent proteolysis blocked RAS-mediated focus formation in fibroblasts and abolished the tumor growth of human pancreatic cancer cells in soft agar as well as in athymic nude mice. Given the high level of conservation of RAS and SIAH function, our study provides useful insights into altered proteolysis in the RAS pathway in tumor initiation, progression, and oncogenesis. By targeting SIAH, we have found a novel means to contravene oncogenic RAS signaling and block RAS-mediated transformation/tumorigenesis. Thus, SIAH may offer a novel therapeutic target to halt tumor growth and ameliorate RAS-mediated pancreatic cancer.