Successful treatment of immune checkpoint inhibitor-related periaortitis.

We report a 64-year-old patient with melanoma receiving ipilimumab and nivolumab therapy who presented with a periaortic soft tissue mass around the abdominal aorta on restaging fluorodeoxyglucose positron emission tomography/computed tomography imaging. Clinical, laboratory, and radiologic findings resulted in a diagnosis of immune checkpoint inhibitor-related periaortitis. Periaortitis is a rare disease presenting with fibro-inflammatory tissue around the aorta and may lead to serious complications. Immune checkpoint inhibitors were discontinued, and the patient was treated with glucocorticoids, leading to a complete resolution of the periaortitis. To our knowledge, this is only the third reported case of immune checkpoint inhibitor-related periaortitis.

Splenic red pulp macrophages provide a niche for CML stem cells and induce therapy resistance.

Disease progression and relapse of chronic myeloid leukemia (CML) are caused by therapy resistant leukemia stem cells (LSCs), and cure relies on their eradication. The microenvironment in the bone marrow (BM) is known to contribute to LSC maintenance and resistance. Although leukemic infiltration of the spleen is a hallmark of CML, it is unknown whether spleen cells form a niche that maintains LSCs. Here, we demonstrate that LSCs preferentially accumulate in the spleen and contribute to disease progression. Spleen LSCs were located in the red pulp close to red pulp macrophages (RPM) in CML patients and in a murine CML model. Pharmacologic and genetic depletion of RPM reduced LSCs and decreased their cell cycling activity in the spleen. Gene expression analysis revealed enriched stemness and decreased myeloid lineage differentiation in spleen leukemic stem and progenitor cells (LSPCs). These results demonstrate that splenic RPM form a niche that maintains CML LSCs in a quiescent state, resulting in disease progression and resistance to therapy.

TNIK signaling imprints CD8+ T cell memory formation early after priming.

Co-stimulatory signals, cytokines and transcription factors regulate the balance between effector and memory cell differentiation during T cell activation. Here, we analyse the role of the TRAF2-/NCK-interacting kinase (TNIK), a signaling molecule downstream of the tumor necrosis factor superfamily receptors such as CD27, in the regulation of CD8+ T cell fate during acute infection with lymphocytic choriomeningitis virus. Priming of CD8+ T cells induces a TNIK-dependent nuclear translocation of ß-catenin with consecutive Wnt pathway activation. TNIK-deficiency during T cell activation results in enhanced differentiation towards effector cells, glycolysis and apoptosis. TNIK signaling enriches for memory precursors by favouring symmetric over asymmetric cell division. This enlarges the pool of memory CD8+ T cells and increases their capacity to expand after re-infection in serial re-transplantation experiments. These findings reveal that TNIK is an important regulator of effector and memory T cell differentiation and induces a population of stem cell-like memory T cells.

mTOR mediates a mechanism of resistance to chemotherapy and defines a rational combination strategy to treat KRAS-mutant lung cancer.

Oncogenic KRAS mutations comprise the largest subset of lung cancer defined by genetic alterations, but in the clinic no targeted therapies are available that effectively control mutational KRAS activation. Consequently, patients with KRAS-driven tumors are routinely treated with cytotoxic chemotherapy, which is often transiently effective owing to development of drug resistance. In this study, we show that hyperactivated mammalian target of rapamycin (mTOR) pathway is a characteristic hallmark of KRAS-mutant lung adenocarcinoma after chemotherapy treatment, and that KRAS-mutant lung cancer cells rely on persistent mTOR signaling to resist chemotherapeutic drugs. Coherently, mTOR inhibition circumvents the refractory phenotype and restores sensitivity of resistant KRAS-mutant lung cancer cells to chemotherapy. Importantly, drug combinations of clinically approved mTOR inhibitors and chemotherapy drugs synergize in inhibiting cell proliferation of KRAS-mutant cancer cells in vitro and in vivo, and the efficacy of this combination treatment correlates with the magnitude of mTOR activity induced by chemotherapy alone. These results pinpoint mTOR as a mechanism of resistance to chemotherapy in KRAS-mutant lung cancer and validate a rational and readily translatable strategy that combines mTOR inhibitors with standard chemotherapy to treat KRAS-mutant adenocarcinoma, the most common and deadliest lung cancer subset.

T-cell-Secreted TNFα Induces Emergency Myelopoiesis and Myeloid-Derived Suppressor Cell Differentiation in Cancer.

Hematopoiesis in patients with cancer is characterized by reduced production of red blood cells and an increase in myelopoiesis, which contributes to the immunosuppressive environment in cancer. Some tumors produce growth factors that directly stimulate myelopoiesis such as G-CSF or GM-CSF. However, for a majority of tumors that do not directly secrete hematopoietic growth factors, the mechanisms involved in the activation of myelopoiesis are poorly characterized. In this study, we document in different murine tumor models activated hematopoiesis with increased proliferation of long-term and short-term hematopoietic stem cells and myeloid progenitor cells. As a consequence, the frequency of myeloid-derived suppressor cells and its ratio to CD8+ T cells increased in tumor-bearing mice. Activation of hematopoiesis and myeloid differentiation in tumor-bearing mice was induced by TNFα, which was mainly secreted by activated CD4+ T cells. Therefore, the activated adaptive immune system in cancer induces emergency myelopoiesis and immunosuppression. SIGNIFICANCE: These findings characterize a regulatory circuit linking activated T cells to suppression of tumor-specific immune responses, providing a conceptual advance in the understanding of emergency-hematopoiesis in cancer and opening new targets for therapeutic approaches. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/79/2/346/F1.large.jpg.

CD70/CD27 signaling promotes blast stemness and is a viable therapeutic target in acute myeloid leukemia.

Aberrant proliferation, symmetric self-renewal, increased survival, and defective differentiation of malignant blasts are key oncogenic drivers in acute myeloid leukemia (AML). Stem cell gene signatures predict poor prognosis in AML patients; however, with few exceptions, these deregulated molecular pathways cannot be targeted therapeutically. In this study, we demonstrate that the TNF superfamily ligand-receptor pair CD70/CD27 is expressed on AML blasts and AML stem/progenitor cells. CD70/CD27 signaling in AML cells activates stem cell gene expression programs, including the Wnt pathway, and promotes symmetric cell divisions and proliferation. Soluble CD27, reflecting the extent of CD70/CD27 interactions in vivo, was significantly elevated in the sera of newly diagnosed AML patients and is a strong independent negative prognostic biomarker for overall survival. Blocking the CD70/CD27 interaction by mAb induced asymmetric cell divisions and differentiation in AML blasts and AML stem/progenitor cells, inhibited cell growth and colony formation, and significantly prolonged survival in murine AML xenografts. Importantly, hematopoietic stem/progenitor cells from healthy BM donors express neither CD70 nor CD27 and were unaffected by blocking mAb treatment. Therefore, targeting CD70/CD27 signaling represents a promising therapeutic strategy for AML.

Implementing barcode medication administration: nurses' attitudes.

To reduce administration-related medication errors hospitals are implementing Barcode Medication Administration (BCMA). This 3-phase study examines nurses' expectations, experiences and attitudes related to BCMA before, during and after implementation. Physical artifacts (carts, scanners, batteries) associated with BCMA can be sources of negative attitudes toward the system.