Benefits and Process of Providing Peer Support for Pediatric Burn Survivors and Caregivers during Inpatient and Outpatient Phases of Recovery.

The World Health Organization reveals that pediatric burns represent a large portion of burns globally (61). Increases in survival rates have guided clinical and research focus on physical, psychological, and social outcomes. Research on other childhood illnesses has shown the efficacy of social support throughout recovery. In the pediatric burn literature, studies have shown the efficacy of burn camps for promoting positive interactions among survivors, learning coping skills, and facilitating socialization and reintegration. However, few studies have focused on the benefits of peer support for pediatric burn survivors and their caregivers in the inpatient and outpatient phases of recovery. This descriptive paper identifies options for building resilience for pediatric burn survivors through peer support in the inpatient and outpatient phases of recovery. The authors discuss options for providing peer support during the coronavirus disease 2019 pandemic on the pediatric intensive care unit, general pediatric floor, and outpatient setting.

Sorafenib inhibits proliferation and invasion in desmoid-derived cells by targeting Ras/MEK/ERK and PI3K/Akt/mTOR pathways.

Desmoid tumors (DTs) are unusual neoplasms of mesenchymal origin that exhibit locally invasive behavior. Surgical resection is the initial treatment of choice for DTs. For patients with recurrent or unresectable disease, however, medical options are limited. Sorafenib is a multikinase inhibitor with known antitumor activity in various cancers via suppression of the PI3K/Akt/mTOR pathway. Here, we examined the effects of sorafenib on patient-derived DT cell lines, with the aim of characterizing the efficacy and molecular mechanism of action. Early passage DT-derived cells were treated with increasing doses of sorafenib (0-10 µM) and demonstrated up to 90% decrease in proliferation and invasion relative to controls. Signaling arrays identified multiple potential targets of sorafenib in the Ras/MEK/ERK and PI3K/Akt/mTOR signaling cascades. Immunoblot analysis revealed that sorafenib inhibited Akt, MEK and ERK phosphorylation, and this effect correlated with inhibition of total Akt and total MEK, while total ERK levels remained unchanged. Sorafenib also inhibited 4E-BP1 phosphorylation, and this effect correlated with decrease of p-eIF4E and total eIF4E. Finally, in combination with the mammalian target of rapamycin (mTOR) inhibitor everolimus, sorafenib decreased phosphorylation of the ribosomal protein and mTOR effector S6K in an additive manner. Taken together, our results suggest that sorafenib suppresses DT proliferation and invasion via inhibition of Ras/MEK/ERK and PI3K/Akt/mTOR signaling pathways with additional effects on translation. Sorafenib may be a promising therapeutic option in the treatment of DTs. Additional studies in DT patients are warranted to examine the efficacy of combination therapy using sorafenib.

Low Serum Vitamin D During Remission Increases Risk of Clinical Relapse in Patients With Ulcerative Colitis.

BACKGROUND & AIMS: Vitamin D levels have been associated with disease activity in patients with ulcerative colitis (UC), but it is unclear whether they affect the risk of disease relapse. We sought to determine the association between baseline vitamin D levels during a period of clinical remission and risk of subsequent UC relapse. METHODS: We performed a physician-blinded prospective study of 70 patients with UC in clinical remission followed up after a surveillance colonoscopy at a tertiary academic medical center. Serum samples were collected at the time of colonoscopy and baseline endoscopic and histologic activity were determined. Levels of 25-hydroxy-vitamin D were measured using an enzyme-linked immunosorbent assay. The primary outcome was rate of clinical relapse, determined over 12 months. RESULTS: The mean baseline vitamin D level was lower among patients with relapse (29.5 ng/mL) than without (50.3 ng/mL) (P = .001). Remission vitamin D level (≤35 ng/mL) was associated with a risk of clinical relapse (odds ratio, 1.25; 95% confidence interval [CI], 1.01-1.56; P = .044) over 12 months, independent of endoscopic or histologic grade at enrollment. A receiver operating characteristic curve of vitamin D levels for the outcome of relapse had an area under the curve of 0.72; and a serum level of 35 ng/mL or less had a sensitivity of 70% (95% CI, 46%-88%) and a specificity of 74% (95% CI 57%-83%) for predicting risk of clinical relapse. CONCLUSIONS: Serum levels of vitamin D of 35 ng/mL or less during periods of clinical remission increase the risk of UC relapse. Clinical trials to obtain vitamin D levels higher than this threshold should be considered.

Design of a small molecule against an oncogenic noncoding RNA.

The design of precision, preclinical therapeutics from sequence is difficult, but advances in this area, particularly those focused on rational design, could quickly transform the sequence of disease-causing gene products into lead modalities. Herein, we describe the use of Inforna, a computational approach that enables the rational design of small molecules targeting RNA to quickly provide a potent modulator of oncogenic microRNA-96 (miR-96). We mined the secondary structure of primary microRNA-96 (pri-miR-96) hairpin precursor against a database of RNA motif-small molecule interactions, which identified modules that bound RNA motifs nearby and in the Drosha processing site. Precise linking of these modules together provided Targaprimir-96 (3), which selectively modulates miR-96 production in cancer cells and triggers apoptosis. Importantly, the compound is ineffective on healthy breast cells, and exogenous overexpression of pri-miR-96 reduced compound potency in breast cancer cells. Chemical Cross-Linking and Isolation by Pull-Down (Chem-CLIP), a small-molecule RNA target validation approach, shows that 3 directly engages pri-miR-96 in breast cancer cells. In vivo, 3 has a favorable pharmacokinetic profile and decreases tumor burden in a mouse model of triple-negative breast cancer. Thus, rational design can quickly produce precision, in vivo bioactive lead small molecules against hard-to-treat cancers by targeting oncogenic noncoding RNAs, advancing a disease-to-gene-to-drug paradigm.

Therapeutic targeting of casein kinase 1δ in breast cancer.

Identification of specific drivers of human cancer is required to instruct the development of targeted therapeutics. We demonstrate that CSNK1D is amplified and/or overexpressed in human breast tumors and that casein kinase 1δ (CK1δ) is a vulnerability of human breast cancer subtypes overexpressing this kinase. Specifically, selective knockdown of CK1δ, or treatment with a highly selective and potent CK1δ inhibitor, triggers apoptosis of CK1δ-expressing breast tumor cells ex vivo, tumor regression in orthotopic models of triple-negative breast cancer, including patient-derived xenografts, and tumor growth inhibition in human epidermal growth factor receptor 2-positive (HER2(+)) breast cancer models. We also show that Wnt/ß-catenin signaling is a hallmark of human tumors overexpressing CK1δ, that disabling CK1δ blocks nuclear accumulation of ß-catenin and T cell factor transcriptional activity, and that constitutively active ß-catenin overrides the effects of inhibition or silencing of CK1δ. Thus, CK1δ inhibition represents a promising strategy for targeted treatment in human breast cancer with Wnt/ß-catenin involvement.

Identification of an EGFRvIII-JNK2-HGF/c-Met-Signaling Axis Required for Intercellular Crosstalk and Glioblastoma Multiforme Cell Invasion.

Glioblastoma multiforme (GBM) is the most aggressive and common form of adult brain cancer. Current therapeutic strategies include surgical resection, followed by radiotherapy and chemotherapy. Despite such aggressive multimodal therapy, prognosis remains poor, with a median patient survival of 14 months. A proper understanding of the molecular drivers responsible for GBM progression are therefore necessary to instruct the development of novel targeted agents and enable the design of effective treatment strategies. Activation of the c-Jun N-terminal kinase isoform 2 (JNK2) is reported in primary brain cancers, where it associates with the histologic grade and amplification of the epidermal growth factor receptor (EGFR). In this manuscript, we demonstrate an important role for JNK2 in the tumor promoting an invasive capacity of EGFR variant III, a constitutively active mutant form of the receptor commonly found in GBM. Expression of EGFR variant III induces transactivation of JNK2 in GBM cells, which is required for a tumorigenic phenotype in vivo. Furthermore, JNK2 expression and activity is required to promote increased cellular invasion through stimulation of a hepatocyte growth factor-c-Met signaling circuit, whereby secretion of this extracellular ligand activates the receptor tyrosine kinase in both a cell autonomous and nonautonomous manner. Collectively, these findings demonstrate the cooperative and parallel activation of multiple RTKs in GBM and suggest that the development of selective JNK2 inhibitors could be therapeutically beneficial either as single agents or in combination with inhibitors of EGFR and/or c-Met.

Macrophage-Induced Blood Vessels Guide Schwann Cell-Mediated Regeneration of Peripheral Nerves.

The peripheral nervous system has remarkable regenerative capacities in that it can repair a fully cut nerve. This requires Schwann cells to migrate collectively to guide regrowing axons across a 'bridge' of new tissue, which forms to reconnect a severed nerve. Here we show that blood vessels direct the migrating cords of Schwann cells. This multicellular process is initiated by hypoxia, selectively sensed by macrophages within the bridge, which via VEGF-A secretion induce a polarized vasculature that relieves the hypoxia. Schwann cells then use the blood vessels as "tracks" to cross the bridge taking regrowing axons with them. Importantly, disrupting the organization of the newly formed blood vessels in vivo, either by inhibiting the angiogenic signal or by re-orienting them, compromises Schwann cell directionality resulting in defective nerve repair. This study provides important insights into how the choreography of multiple cell-types is required for the regeneration of an adult tissue.

Development of an HTS-Compatible Assay for the Discovery of Ulk1 Inhibitors.

A rapidly accumulating body of work suggests the autophagy pathway is an attractive therapeutic target for neurodegenerative diseases and cancer. To validate autophagy as an anticancer strategy and to assess if systemic inhibition of the pathway will have deleterious effects on normal tissues and physiology, highly selective autophagy inhibitors are needed. While several inducers and inhibitors of autophagy are known, all are nonspecific and none target the enzymes that execute the pathway. A central upstream regulator of the autophagy pathway is the serine/threonine kinase Ulk1 (UNC-51-like kinase-1). Selective molecular probes that function as Ulk1-specific inhibitors are needed to improve our understanding of the autophagy pathway. To identify inhibitors of Ulk1 kinase activity, we developed an HTS-compatible, homogeneous biochemical assay using AlphaScreen technology. This novel assay design uses purified stress-activated Ulk1 and monitors phosphorylation of its full-length native substrate, Atg13. This assay was optimized and validated in a 384-well format by screening the Sigma LOPAC library. Here we report that the Ulk1 AlphaScreen assay is robust and reproducible, with a Z' factor value of 0.83 ± 0.02 and a signal to background ratio of 20 ± 1.2. Thus, this assay can be used to screen large chemical libraries to discover novel inhibitors of Ulk1.

Antitumor effects of hyaluronan inhibition in desmoid tumors.

Desmoid tumors (DTs) are rare, mesenchymal tumors that exhibit features of an abundant wound healing process. Previously, we showed that mesenchymal stem cells (MSCs) are constituents of DTs and may contribute to desmoid tumorigenesis via activities associated with wound healing. Hyaluronan (HA) is a long-charged chain of repeating glucuronate and N-acetylglucosamine disaccharides that is synthesized by HA synthases (HAS) and degraded by hyaluronidases (HYAL). HA is secreted into the extracellular matrix by injured stroma and is important for normal tissue repair and neoplastic progression. Here, we investigated the presence of HA in DTs and the antitumor effects of the HA inhibitor, 4-methylumbelliferone (4-MU), on DT-derived mesenchymal cells. By immunohistochemistry and enzyme-linked immunosorbent assay, we found abundant expression of HA in 29/30 DTs as well as >5-fold increased HA levels in DT-derived cell lines relative to controls. Immunohistochemistry also demonstrated high expression of HAS2 in DTs, and quantitative PCR analysis showed increased HAS2 upregulation in frozen DTs and DT-derived cells. 4-MU treatment of DT-derived cells significantly decreased proliferation as well as HA and HAS2 levels. Fluorescent immunohistochemistry showed that MSCs in DTs coexpressed HA, HAS2, HYAL2, as well as the major HA receptor CD44 and HA coreceptor TLR4. Taken together, our results suggest that paracrine regulation of HA signaling in DTs may contribute to MSC recruitment and tumor proliferation. Future studies investigating the role of HA in tumor-stroma crosstalk and inhibition of HA-MSC interactions as a novel therapeutic target in DTs and other solid tumors are warranted.

Development of highly selective casein kinase 1δ/1ε (CK1δ/ε) inhibitors with potent antiproliferative properties.

The development of a series of potent and highly selective casein kinase 1δ/ε (CK1δ/ε) inhibitors is described. Starting from a purine scaffold inhibitor (SR-653234) identified by high throughput screening, we developed a series of potent and highly kinase selective inhibitors, including SR-2890 and SR-3029, which have IC50 ≤ 50 nM versus CK1δ. The two lead compounds have ≤100 nM EC50 values in MTT assays against the human A375 melanoma cell line and have physical, in vitro and in vivo PK properties suitable for use in proof of principle animal xenograft studies against human cancer cell lines.

Histologic markers of inflammation in patients with ulcerative colitis in clinical remission.

BACKGROUND & AIMS: Mucosal healing, based on histologic analysis, is an end point of maintenance therapy for patients with ulcerative colitis (UC). There are few data on how histologic signs of inflammation correlate with endoscopic and peripheral blood measures of inflammation in these patients. We investigated patterns of histologic features of inflammation in patients with UC in clinical remission, and correlated these with endoscopic and biochemical measures of inflammation. METHODS: We performed a prospective observational study of 103 patients with UC in clinical remission undergoing surveillance colonoscopy while receiving maintenance therapy with mesalamine or thiopurines; 2674 biopsy specimens were collected from 708 colonic segments. Each colonic segment was evaluated based on the Mayo endoscopic subscore and the Geboes histology score (range, 0-5.4). Biomarkers were measured in peripheral blood samples. RESULTS: Histologic features of inflammation were found in 54% of patients receiving maintenance therapy; 37% had at least moderate inflammation based on histology scores. Of the 52 patients with endoscopic evidence only of left-sided colitis, 34% had histologic features of inflammation in their proximal colon. Histology scores correlated with endoscopic scores for per-segment inflammation (Spearman ρ = 0.65; P < .001). Patients with histology scores greater than 3.1 had a significantly higher mean level of C-reactive protein than those with scores less than 3.1. There were no differences among treatment groups in percentages of patients with histologic scores greater than 3.1. CONCLUSIONS: Patients in clinical remission from UC still frequently have histologic features of inflammation, which correlate with endoscopic appearance. Patients with at least moderate levels of inflammation, based on histologic grading (score >3.1), have higher serum levels of C-reactive protein, which could be used as a surrogate marker of histologic inflammation.

Predictors of endoscopic inflammation in patients with ulcerative colitis in clinical remission.

BACKGROUND: Patients with ulcerative colitis (UC) who are in clinical remission may still have underlying endoscopic inflammation, which is associated with inferior clinical outcomes. The goal of this study was to determine the prevalence of active endoscopic disease, and factors associated with it, in patients with UC who are in clinical remission. METHODS: Prospective observational study in a single center. Patients with UC in clinical remission (by Simple Clinical Colitis Activity Index) were enrolled prospectively at the time of surveillance colonoscopy. Disease phenotype, endoscopic activity (Mayo subscore), and histologic score (Geboes) were recorded, and blood was drawn for peripheral blood biomarkers. RESULTS: Overall, 149 patients in clinical remission were prospectively enrolled in this cohort; 81% had been in clinical remission for >6 months, and 86% were currently prescribed maintenance medications. At endoscopy, 45% of patients in clinical remission had any endoscopic inflammation (Mayo endoscopy subscore >0), and 13% had scores >1. In a multivariate model, variables independently associated with a Mayo endoscopic score >1 were remission for <6 months (P = 0.001), white blood count (P = 0.01), and C-reactive protein level (P = 0.009). A model combining these 3 variables had a sensitivity of 94% and a specificity of 73% for predicting moderate-to-severe endoscopic activity in patients in clinical remission (area under the curve, 0.86). In an unselected subgroup of patients who had peripheral blood mononuclear cell messenger RNA profiling, GATA3 messenger RNA levels were significantly higher in patients with endoscopic activity. CONCLUSIONS: Duration of clinical remission, white blood count, and C-reactive protein level can predict the probability of ongoing endoscopic activity, despite clinical remission in patients with UC. These parameters could be used to identify patients who require intensification of treatment to achieve mucosal healing.

Targeting the MAGE A3 antigen in pancreatic cancer.

Pancreatic cancer is the fourth-leading cause of death in the United States and one of the most aggressive known malignancies. New and innovative advances in treatment are desperately needed. One promising area of investigational treatment for pancreatic cancer involves the use of immunotherapy. The development of immunotherapy for pancreatic cancer has been hampered by difficulty in generating tumor-reactive lymphocytes from resected specimens and by a lack of appropriate target antigens expressed on tumor cells. Innovative strategies have been developed with the use of peripheral blood lymphocytes that are genetically engineered to express T-cell receptors targeting common tumor antigens, including cancer-testis antigens, such as the MAGE-A3 antigen. Cancer-testis antigens pose excellent targets for immunotherapy because they are expressed in cancer and in the testis, an immune-privileged site, but have limited expression in normal tissue. An additional advantage in targeting cancer-testis antigens for immunotherapy is that their expression can be selectively up-regulated in tumor cells via epigenetic regulation with chromatin remodeling agents. Current interest in targeting cancer-testis antigens in pancreatic cancer is well-founded because cancer-testis antigens have been shown to be expressed in pancreatic cancer as potential targets for therapy. In our studies, we validated the expression pattern of cancer-testis antigens in resected specimens of pancreatic cancer and tested the hypothesis that treatment of pancreatic cancer cells with chromatin remodeling agents would render them more sensitive to antigen-specific T lymphocytes. We focused predominately on the MAGE-A3 antigen because it is highly expressed in pancreatic cancer, and several immunotherapeutic strategies are in clinical trials targeting this specific antigen. The results of these studies have important translational implications and provide the rationale for combined treatment with chromatin remodeling agents and immunotherapeutic approaches for pancreatic cancer.

A central role for the ERK-signaling pathway in controlling Schwann cell plasticity and peripheral nerve regeneration in vivo.

Following damage to peripheral nerves, a remarkable process of clearance and regeneration takes place. Axons downstream of the injury degenerate, while the nerve is remodeled to direct axonal regrowth. Schwann cells are important for this regenerative process. "Sensing" damaged axons, they dedifferentiate to a progenitor-like state, in which they aid nerve regeneration. Here, we demonstrate that activation of an inducible Raf-kinase transgene in myelinated Schwann cells is sufficient to control this plasticity by inducing severe demyelination in the absence of axonal damage, with the period of demyelination/ataxia determined by the duration of Raf activation. Remarkably, activation of Raf-kinase also induces much of the inflammatory response important for nerve repair, including breakdown of the blood-nerve barrier and the influx of inflammatory cells. This reversible in vivo model identifies a central role for ERK signaling in Schwann cells in orchestrating nerve repair and is a powerful system for studying peripheral neuropathies and cancer.

NF1 loss disrupts Schwann cell-axonal interactions: a novel role for semaphorin 4F.

Neurofibromatosis type 1 (NF1) patients develop neurofibromas, tumors of Schwann cell origin, as a result of loss of the Ras-GAP neurofibromin. In normal nerves, Schwann cells are found tightly associated with axons, while loss of axonal contact is a frequent and important early event in neurofibroma development. However, the molecular basis of this physical interaction or how it is disrupted in cancer remains unclear. Here we show that loss of neurofibromin in Schwann cells is sufficient to disrupt Schwann cell/axonal interactions via up-regulation of the Ras/Raf/ERK signaling pathway. Importantly, we identify down-regulation of semaphorin 4F (Sema4F) as the molecular mechanism responsible for the Ras-mediated loss of interactions. In heterotypic cocultures, Sema4F knockdown induced Schwann cell proliferation by relieving axonal contact-inhibitory signals, providing a mechanism through which loss of axonal contact contributes to tumorigenesis. Importantly, Sema4F levels were strongly reduced in a panel of human neurofibromas, confirming the relevance of these findings to the human disease. This work identifies a novel role for the guidance-molecules semaphorins in the mediation of Schwann cell/axonal interactions, and provides a molecular mechanism by which heterotypic cell-cell contacts control cell proliferation and suppress tumorigenesis. Finally, it provides a new approach for the development of therapies for NF1.

Initiation of a critical pathway for pancreaticoduodenectomy at an academic institution--the first step in multidisciplinary team building.

BACKGROUND: Pancreaticoduodenectomy (PD) is a complex general surgical procedure originally associated with significant perioperative morbidity and mortality. Multiple studies have now shown that this operation can be performed quite safely at high-volume institutions that develop a particular expertise. Critical pathways are among the key tools used to achieve consistently excellent outcomes at these institutions. It remains to be determined if implementation of a critical pathway at an academic institution with earlier moderate experience with PD will result in performance gains and improved outcomes. This study was designed to track performance improvements brought about by the implementation of a critical pathway for complex alimentary tract surgery. STUDY DESIGN: Between January 1, 2004, and October 15, 2006, 135 patients underwent PD: 44 before implementation of a critical pathway on October 15, 2005, and 91 after. Perioperative and postoperative parameters were analyzed retrospectively to identify those that could be used to track performance improvement and outcomes. RESULTS: Compared with the prepathway group, the postpathway group had a significantly shorter postoperative length of stay (13 versus 7 days, p < or = 0.0001) and operative time. Mean total hospital charges were significantly reduced, from $240,242 +/- $32,490 to $126,566 +/- $4,883 (p < or = 0.0001). CONCLUSIONS: Implementation of a critical pathway for a complex procedure can be demonstrated to improve short-term outcomes at an academic institution. This improvement can be quantified and tracked and has implications for better use of resources (greater operating room and hospital bed availability) and overall cost containment.

Activation of Akt and eIF4E survival pathways by rapamycin-mediated mammalian target of rapamycin inhibition.

The mammalian target of rapamycin (mTOR) has emerged as an important cancer therapeutic target. Rapamycin and its derivatives that specifically inhibit mTOR are now being actively evaluated in clinical trials. Recently, the inhibition of mTOR has been shown to reverse Akt-dependent prostate intraepithelial neoplasia. However, many cancer cells are resistant to rapamycin and its derivatives. The mechanism of this resistance remains a subject of major therapeutic significance. Here we report that the inhibition of mTOR by rapamycin triggers the activation of two survival signaling pathways that may contribute to drug resistance. Treatment of human lung cancer cells with rapamycin suppressed the phosphorylation of p70S6 kinase and 4E-BP1, indicating an inhibition of mTOR signaling. Paradoxically, rapamycin also concurrently increased the phosphorylation of both Akt and eIF4E. The rapamycin-induced phosphorylation of Akt and eIF4E was suppressed by the phosphatidylinositol-3 kinase (PI3K) inhibitor LY294002, suggesting the requirement of PI3K in this process. The activated Akt and eIF4E seem to attenuate rapamycin's growth-inhibitory effects, serving as a negative feedback mechanism. In support of this model, rapamycin combined with LY294002 exhibited enhanced inhibitory effects on the growth and colony formation of cancer cells. Thus, our study provides a mechanistic basis for enhancing mTOR-targeted cancer therapy by combining an mTOR inhibitor with a PI3K or Akt inhibitor.