Primary Mediastinal Large B-Cell Lymphoma Presenting as Acute Pancreatitis.

Pancreatitis is an inflammatory pancreatic disease; common etiologies include infection, anatomic abnormalities, biliary, inborn errors of metabolism, trauma, and rarely malignancy. Primary mediastinal large B-cell lymphoma commonly presents in younger women with principally mediastinal involvement. We report the first documented case of a pediatric patient presenting with acute pancreatitis secondary to metastatic primary mediastinal large B-cell lymphoma. Since diagnosis, the patient underwent a combination of chemotherapy and immunotherapy treatments, and the tumor burden had decreased significantly. Malignancy is a rare documented presentation of acute pancreatitis in the pediatric population, and it should be included in a broad differential diagnosis.

Between a Rock and a Hard Place: Anticoagulating an Adolescent with Post-Tonsillectomy Massive PE: A Case Report.

OBJECTIVES: To report a case of a morbidly obese 17-year-old boy who presented 4 days post-tonsillectomy with acute deep venous thromboses and a massive pulmonary embolism. To describe a protocol and decision-making tree for providing anticoagulation in the immediate post-tonsillectomy period. METHODS: A chart review and review of the literature. RESULTS: The patient ultimately did well and had no bleeding from the tonsil beds or further thromboembolic complications. A review of the literature revealed no available data regarding the safety of anticoagulation in the immediate post-tonsillectomy period. CONCLUSIONS: We propose that if anticoagulation is needed within 14 days of tonsillectomy, submaximal anticoagulation with a reversible and titratable anticoagulant may be optimal. A multidisciplinary team approach is needed for these complex cases. Future reporting and investigation of anticoagulation post-tonsillectomy is needed.

Effect of Poloxamer 188 vs Placebo on Painful Vaso-Occlusive Episodes in Children and Adults With Sickle Cell Disease: A Randomized Clinical Trial.

Importance: Although effective agents are available to prevent painful vaso-occlusive episodes of sickle cell disease (SCD), there are no disease-modifying therapies for ongoing painful vaso-occlusive episodes; treatment remains supportive. A previous phase 3 trial of poloxamer 188 reported shortened duration of painful vaso-occlusive episodes in SCD, particularly in children and participants treated with hydroxyurea. Objective: To reassess the efficacy of poloxamer 188 for vaso-occlusive episodes. Design, Setting, and Participants: Phase 3, randomized, double-blind, placebo-controlled, multicenter, international trial conducted from May 2013 to February 2016 that included 66 hospitals in 12 countries and 60 cities; 388 individuals with SCD (hemoglobin SS, SC, S-ß0 thalassemia, or S-ß+ thalassemia disease) aged 4 to 65 years with acute moderate to severe pain typical of painful vaso-occlusive episodes requiring hospitalization were included. Interventions: A 1-hour 100-mg/kg loading dose of poloxamer 188 intravenously followed by a 12-hour to 48-hour 30-mg/kg/h continuous infusion (n = 194) or placebo (n = 194). Main Outcomes and Measures: Time in hours from randomization to the last dose of parenteral opioids among all participants and among those younger than 16 years as a separate subgroup. Results: Of 437 participants assessed for eligibility, 388 were randomized (mean age, 15.2 years; 176 [45.4%] female), the primary outcome was available for 384 (99.0%), 15-day follow-up contacts were available for 357 (92.0%), and 30-day follow-up contacts were available for 368 (94.8%). There was no significant difference between the groups for the mean time to last dose of parenteral opioids (81.8 h for the poloxamer 188 group vs 77.8 h for the placebo group; difference, 4.0 h [95% CI, -7.8 to 15.7]; geometric mean ratio, 1.2 [95% CI, 1.0-1.5]; P = .09). Based on a significant interaction of age and treatment (P = .01), there was a treatment difference in time from randomization to last administration of parenteral opioids for participants younger than 16 years (88.7 h in the poloxamer 188 group vs 71.9 h in the placebo group; difference, 16.8 h [95% CI, 1.7-32.0]; geometric mean ratio, 1.4 [95% CI, 1.1-1.8]; P = .008). Adverse events that were more common in the poloxamer 188 group than the placebo group included hyperbilirubinemia (12.7% vs 5.2%); those more common in the placebo group included hypoxia (12.0% vs 5.3%). Conclusions and Relevance: Among children and adults with SCD, poloxamer 188 did not significantly shorten time to last dose of parenteral opioids during vaso-occlusive episodes. These findings do not support the use of poloxamer 188 for vaso-occlusive episodes. Trial Registration: ClinicalTrials.gov Identifier: NCT01737814.

CDKN1A and FANCD2 are potential oncotargets in Burkitt lymphoma and multiple myeloma.

BACKGROUND: Comparative genetic and biological studies on malignant tumor counterparts in human beings and laboratory mice may be powerful gene discovery tools for blood cancers, including neoplasms of mature B-lymphocytes and plasma cells such as Burkitt lymphoma (BL) and multiple myeloma (MM). METHODS: We used EMSA to detect constitutive NF-κB/STAT3 activity in BL- and MM-like neoplasms that spontaneously developed in single-transgenic IL6 (interleukin-6) or MYC (c-Myc) mice, or in double-transgenic IL6MYC mice. qPCR measurements and analysis of clinical BL and MM datasets were employed to validate candidate NF-κB/STAT3 target genes. RESULTS: qPCR demonstrated that IL6- and/or MYC-dependent neoplasms in mice invariably contain elevated mRNA levels of the NF-κB target genes, Cdkn1a and Fancd2. Clinical studies on human CDKN1A, which encodes the cell cycle inhibitor and tumor suppressor p21, revealed that high p21 message predicts poor therapy response and survival in BL patients. Similarly, up-regulation of FANCD2, which encodes a key member of the Fanconi anemia and breast cancer pathway of DNA repair, was associated with poor outcome of patients with MM, particularly those with high-risk disease. CONCLUSIONS: Our findings suggest that CDKN1A and FANCD2 are potential oncotargets in BL and MM, respectively. Additionally, the IL-6- and/or MYC-driven mouse models of human BL and MM used in this study may lend themselves to the biological validation of CDKN1A and FANCD2 as molecular targets for new approaches to cancer therapy and prevention.

Piperlongumine inhibits the proliferation and survival of B-cell acute lymphoblastic leukemia cell lines irrespective of glucocorticoid resistance.

Piperlongumine (PL), a pepper plant alkaloid from Piper longum, has anti-inflammatory and anti-cancer properties. PL selectively kills both solid and hematologic cancer cells, but not normal counterparts. Here we evaluated the effect of PL on the proliferation and survival of B-cell acute lymphoblastic leukemia (B-ALL), including glucocorticoid (GC)-resistant B-ALL. Regardless of GC-resistance, PL inhibited the proliferation of all B-ALL cell lines, but not normal B cells, in a dose- and time-dependent manner and induced apoptosis via elevation of ROS. Interestingly, PL did not sensitize most of B-ALL cell lines to dexamethasone (DEX). Only UoC-B1 exhibited a weak synergistic effect between PL and DEX. All B-ALL cell lines tested exhibited constitutive activation of multiple transcription factors (TFs), including AP-1, MYC, NF-κB, SP1, STAT1, STAT3, STAT6 and YY1. Treatment of the B-ALL cells with PL significantly downregulated these TFs and modulated their target genes. While activation of AURKB, BIRC5, E2F1, and MYB mRNA levels were significantly downregulated by PL, but SOX4 and XBP levels were increased by PL. Intriguingly, PL also increased the expression of p21 in B-ALL cells through a p53-independent mechanism. Given that these TFs and their target genes play critical roles in a variety of hematological malignancies, our findings provide a strong preclinical rationale for considering PL as a new therapeutic agent for the treatment of B-cell malignancies, including B-ALL and GC-resistant B-ALL.

Choroidal schwannoma in a 6-month-old girl.

Choroidal schwannomas are exceedingly rare in children, with only 6 cases reported in children younger than 18 years of age and none in those younger than 9 years. We report a 6-month-old infant presenting with a large noncalcified amelanotic mass with secondary glaucoma that mimicked an atypical retinoblastoma, leading to emergent enucleation for therapeutic and diagnostic purposes. Pathology revealed a total retinal detachment, glaucomatous damage, and a large mass arising from the peripapillary posterior choroid with areas of Antoni A pattern and S-100 staining consistent with the diagnosis of an intraocular schwannoma. This is the first intraocular schwannoma described in an infant.

A new model of LMP1-MYC interaction in B cell lymphoma.

Epstein-Barr virus (EBV) is associated with aggressive B cell lymphomas (BCLs). Latent membrane protein 1 (LMP1) of EBV is an oncogenic protein required for EBV B cell transformation. However, LMP1 is a weak oncogene in mice. Mice expressing Myc inserted 5' of the Eµ enhancer (iMyc(Eµ)), mimicking the t(8;14) translocation of endemic Burkitt lymphoma, develop delayed onset BCLs. To investigate potential cooperation between LMP1 and oncogenic MYC, we produced mice expressing the LMP1 signaling domain via a hybrid CD40-LMP1 transgene (mCD40-LMP1), and the dysregulated MYC protein of aggressive EBV+ BCLs. mCD40-LMP1/iMyc(Eµ) mice trended toward earlier BCL onset. BCLs from mCD40-LMP1/iMyc(Eµ) mice expressed LMP1 and were transplantable into immunocompetent recipients. iMyc(Eµ) and mCD40-LMP1/iMyc(Eµ) mice developed BCLs with similar immunophenotypes. LMP1 signaling was intact in BCLs as shown by inducible interleukin-6. Additionally, LMP1 signaling to tumor cells induced the two isoforms of Pim1, a constitutively active prosurvival kinase implicated in lymphomagenesis.

Breakthrough varicella in a cancer patient with persistent varicella antibody after one varicella vaccination.

A boy with Hodgkin disease contracted breakthrough varicella from his father, who had chickenpox. The boy had received a single varicella vaccination and was seropositive by enzyme-linked immunosorbent assay before being diagnosed with breakthrough varicella. Seropositivity after a single varicella vaccination does not guarantee complete protection in an immunocompromised child.

Piperlongumine inhibits LMP1/MYC-dependent mouse B-lymphoma cells.

Piperlongumine (PL), isolated from the fruit of Long pepper, Piper longum, is a cancer-inhibiting compound that selectively kills tumor cells while sparing their normal counterparts. Here we evaluated the efficacy with which PL suppresses malignant B cells derived from a newly developed, double-transgenic mouse model of human endemic Burkitt lymphoma (BL), designated mCD40-LMP1/iMyc(Eµ). PL inhibited tumor cell proliferation in a concentration-dependent manner and induced apoptosis of neoplastic but not normal B cells. Treatment with PL resulted in downregulation of EBV-encoded LMP1, cellular Myc, constitutive NF-κB activity, and a host of LMP1-Myc-NF-κB-regulated target genes including Aurka, Bcat1, Bub1b, Ccnb1, Chek1, Fancd2, Tfrc and Xrcc6. Of note, p21(Cip1)-encoding Cdkn1a was suppressed independent of changes in Trp53 mRNA levels and p53 DNA-binding activity. Considering the central role of the LMP1-NF-κB-Myc axis in B-lineage neoplasia, these findings further our understanding of the mechanisms by which PL inhibits B-lymphoma and provide a preclinical rationale for the inclusion of PL in new interventions in blood cancers.

Piperlongumine inhibits proliferation and survival of Burkitt lymphoma in vitro.

Piperlongumine (PL), a pepper plant alkaloid from Piper longum, kills solid tumor cells in a highly selective, potent fashion. To evaluate whether PL may have similar effects on malignant blood cells, we determined the efficacy with which PL inhibits the B-lymphocyte derived neoplasm, Burkitt lymphoma (BL). Low micromolar concentrations of PL (IC(50) = 2.8 µM × 8.5 µM) curbed growth and survival of two EBV(+) BL cell lines (Daudi, Raji) and two EBV BL cell lines (Ramos, DG-75), but left normal peripheral blood B-lymphocytes unharmed. PL-dependent cytotoxicity was effected in part by reduced NF-κB and MYC activity, with the former being caused by inhibition of IκBα degradation, nuclear translocation of p65, and binding of NF-κB dimers to cognate DNA sequences in gene promoters. In 4 of 4 BL cell lines, the NF-κB/MYC-regulated cellular target genes, E2F1 and MYB, were down regulated, while the stress sensor gene, GADD45B, was up regulated. The EBV-encoded oncogene, LMP-1, was suppressed in Daudi and Raji cells. Considering that NF-κB, MYC and LMP-1 play a crucial role in the biology of many blood cancers including BL, our results provide a strong preclinical rationale for considering PL in new intervention approaches for patients with hematologic malignancies.

Itk functions to control actin polymerization at the immune synapse through localized activation of Cdc42 and WASP.

Actin polymerization at the immune synapse is required for T cell activation and effector function; however, the relevant regulatory pathways remain poorly understood. We showed previously that binding to antigen presenting cells (APCs) induces localized activation of Cdc42 and Wiskott-Aldrich Syndrome protein (WASP) at the immune synapse. Several lines of evidence suggest that Tec kinases could interact with WASP-dependent actin regulatory processes. Since T cells from Rlk-/-, Itk-/-, and Rlk-/- x Itk-/- mice have defects in signaling and development, we asked whether Itk or Rlk function in actin polymerization at the immune synapse. We find that Itk-/- and Rlk-/- x Itk-/- T cells are defective in actin polymerization and conjugate formation in response to antigen-pulsed APCs. Itk functions downstream of the TCR, since similar defects were observed upon TCR engagement alone. Using conformation-specific probes, we show that although the recruitment of WASP and Arp2/3 complex to the immune synapse proceeds normally, the localized activation of Cdc42 and WASP is defective. Finally, we find that the defect in Cdc42 activation likely stems from a requirement for Itk in the recruitment of Vav to the immune synapse. Our results identify Itk as a key element of the pathway leading to localized actin polymerization at the immune synapse.