Combination OX40 agonism/CTLA-4 blockade with HER2 vaccination reverses T-cell anergy and promotes survival in tumor-bearing mice.

Immunotherapy is gathering momentum as a primary therapy for cancer patients. However, monotherapies have limited efficacy in improving outcomes and benefit only a subset of patients. Combination therapies targeting multiple pathways can augment an immune response to improve survival further. Here, we demonstrate that dual aOX40 (anti-CD134)/aCTLA-4 (anti-cytotoxic T-lymphocyte-associated protein 4) immunotherapy generated a potent antigen-specific CD8 T-cell response, enhancing expansion, effector function, and memory T-cell persistence. Importantly, OX40 and CTLA-4 expression on CD8 T cells was critical for promoting their maximal expansion following combination therapy. Animals treated with combination therapy and vaccination using anti-DEC-205 (dendritic and epithelial cells, 205 kDa)-HER2 (human epidermal growth factor receptor 2) had significantly improved survival in a mammary carcinoma model. Vaccination with combination therapy uniquely restricted Th2-cytokine production by CD4 cells, relative to combination therapy alone, and enhanced IFNγ production by CD8 and CD4 cells. We observed an increase in MIP-1α (macrophage inflammatory protein-1α)/CCL3 [chemokine (C-C motif) ligand 3], MIP-1ß/CCL4, RANTES (regulated on activation, normal T-cell expressed and excreted)/CCL5, and GM-CSF production by CD8 and CD4 T cells following treatment. Furthermore, this therapy was associated with extensive tumor destruction and T-cell infiltration into the tumor. Notably, in a spontaneous model of prostate adenocarcinoma, vaccination with combination therapy reversed anergy and enhanced the expansion and function of CD8 T cells recognizing a tumor-associated antigen. Collectively, these data demonstrate that the addition of a vaccine with combined aOX40/aCTLA-4 immunotherapy augmented antitumor CD8 T-cell function while limiting Th2 polarization in CD4 cells and improved overall survival.

ALT-803, an IL-15 superagonist, in combination with nivolumab in patients with metastatic non-small cell lung cancer: a non-randomised, open-label, phase 1b trial.

BACKGROUND: Immunotherapy with PD-1 or PD-L1 blockade fails to induce a response in about 80% of patients with unselected non-small cell lung cancer (NSCLC), and many of those who do initially respond then develop resistance to treatment. Agonists that target the shared interleukin-2 (IL-2) and IL-15Rßγ pathway have induced complete and durable responses in some cancers, but no studies have been done to assess the safety or efficacy of these agonists in combination with anti-PD-1 immunotherapy. We aimed to define the safety, tolerability, and activity of this drug combination in patients with NSCLC. METHODS: In this non-randomised, open-label, phase 1b trial, we enrolled patients (aged ≥18 years) with previously treated histologically or cytologically confirmed stage IIIB or IV NSCLC from three academic hospitals in the USA. Key eligibility criteria included measurable disease, eligibility to receive anti-PD-1 immunotherapy, and an Eastern Cooperative Oncology Group performance status of 0 or 1. Patients received the anti-PD-1 monoclonal antibody nivolumab intravenously at 3 mg/kg (then 240 mg when US Food and Drug Administration [FDA]-approved dosing changed) every 14 days (either as new treatment or continued treatment at the time of disease progression) and the IL-15 superagonist ALT-803 subcutaneously once per week on weeks 1-5 of four 6-week cycles for 6 months. ALT-803 was administered at one of four escalating dose concentrations: 6, 10, 15, or 20 µg/kg. The primary endpoint was to define safety and tolerability and to establish a recommended phase 2 dose of ALT-803 in combination with nivolumab. Analyses were per-protocol and included any patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov, number NCT02523469; phase 2 enrolment of patients is ongoing. FINDINGS: Between Jan 18, 2016, and June 28, 2017, 23 patients were enrolled and 21 were treated at four dose levels of ALT-803 in combination with nivolumab. Two patients did not receive treatment because of the development of inter-current illness during enrolment, one patient due to leucopenia and one patient due to pulmonary dysfunction. No dose-limiting toxicities were recorded and the maximum tolerated dose was not reached. The most common adverse events were injection-site reactions (in 19 [90%] of 21 patients) and flu-like symptoms (15 [71%]). The most common grade 3 adverse events, occurring in two patients each, were lymphocytopenia and fatigue. A grade 3 myocardial infarction occurred in one patient. No grade 4 or 5 adverse events were recorded. The recommended phase 2 dose of ALT-803 is 20 µg/kg given once per week subcutaneously in combination with 240 mg intravenous nivolumab every 2 weeks. INTERPRETATION: ALT-803 in combination with nivolumab can be safely administered in an outpatient setting. The promising clinical activity observed with the addition of ALT-803 to the regimen of patients with PD-1 monoclonal antibody relapsed and refractory disease shows evidence of anti-tumour activity for a new class of agents in NSCLC. FUNDING: Altor BioScience (a NantWorks company), National Institutes of Health, and Medical University of South Carolina Hollings Cancer Center.

Multispectral Imaging of T and B Cells in Murine Spleen and Tumor.

Recent advances in multiplex immunohistochemistry techniques allow for quantitative, spatial identification of multiple immune parameters for enhanced diagnostic and prognostic insight. However, applying such techniques to murine fixed tissues, particularly sensitive epitopes, such as CD4, CD8α, and CD19, has been difficult. We compared different fixation protocols and Ag-retrieval techniques and validated the use of multiplex immunohistochemistry for detection of CD3(+)CD4(+) and CD3(+)CD8(+) T cell subsets in murine spleen and tumor. This allows for enumeration of these T cell subsets within immune environments, as well as the study of their spatial distribution.

The role of Galectin-3 in modulating tumor growth and immunosuppression within the tumor microenvironment.

The efficacy of cancer immunotherapy is limited, in part, by the multitude of immunosuppressive mechanisms present within the tumor microenvironment (TME). Galectin-3 (Gal-3) is a lectin that contributes to TME immunosuppression and regulates diverse functions including cellular homeostasis and cancer biology. Increased Gal-3 expression during cancer progression augments tumor growth, invasiveness, metastatic potential, and immune suppression, which highlights the potential use of Gal-3 as a therapeutic target capable of modulating anti-tumor immunity. Here, we discuss the mechanisms by which Gal-3 regulates lymphocytes, the role of Gal-3 in lung and prostate tumors, and the contribution of Gal-3 to TME immunosuppression.

Early evidence of anti-PD-1 activity in enzalutamide-resistant prostate cancer.

While programmed cell death 1 (PD-1) inhibitors have shown clear anti-tumor efficacy in several solid tumors, prior results in men with metastatic castration resistant prostate cancer (mCRPC) showed no evidence of activity. Here we report unexpected antitumor activity seen in mCRPC patients treated with the anti-PD-1 antibody pembrolizumab. Patients with evidence of progression on enzalutamide were treated with pembrolizumab 200 mg IV every 3 weeks for 4 doses; pembrolizumab was added to standard dose enzalutamide. Three of the first ten patients enrolled in this ongoing phase II trial experienced rapid prostate specific antigen (PSA) reductions to ≤ 0.2 ng/ml. Two of these three patients had measurable disease upon study entry; both achieved a partial response. There were three patients with significant immune-related adverse events. One had grade 2 myositis, one had grade 3 hypothyroidism, and one had grade 2 hypothyroidism. None of these patients had a response. Two of the three responders had a baseline tumor biopsy. Immunohistochemistry from those biopsies showed the presence of CD3+, CD8+, and CD163+ leukocyte infiltrates and PD-L1 expression. Genetic analysis of the two responders revealed markers of microsatellite instability in one. The surprising and robust responses seen in this study should lead to re-examination of PD-1 inhibition in prostate cancer.

Endotracheal intubation without muscle relaxants in children using remifentanil and propofol: Comparative study.

INTRODUCTION: Endotracheal intubation is essential during general anesthesia and muscle relaxant drugs provide ideal conditions for this purpose. The objective of this study was to evaluate the intubating condition of remifentanil combined with propofol without muscle relaxant. MATERIALS AND METHODS: In this prospective randomized study, 60 children aged 3-12 years, American Society of Anesthesiologists physical status I and II were included. All the children were premedicated with 0.05 mg/kg midazolam and 1.5 mg/kg lidocaine 5 min before the induction of anesthesia with 3 mg/kg propofol. Then, they were allocated randomly to receive either 2 µg/kg remifentanil (group R) or 1.5 mg/kg succinylcholine (group S). Tracheal intubation was attempted 90 s after the administration of propofol. The quality of intubation was assessed by using Copenhagen score based on jaw relaxation, ease of laryngoscopy, position of vocal cord, coughing and limb movement. Heart rate and blood pressure were recorded before and after induction, and 1, 3, 5 min after intubation. RESULTS: There was no significant difference in intubating condition between the two groups (P = 0.11). Intubation condition was excellent in 26 of 30 (86.7%) patients in the group R compared with 30 (100%) patients in the group S. We observed significant difference in heart rate and systolic blood pressure over time between two groups (P = 0.02, P = 0.03 respectively). After intubation, we had higher heart rate and systolic blood pressure with a significant difference in group S compared with group R (P = 0.006, P = 0.018). None of the children had a chest rigidity, laryngospasm, and hypoxia. CONCLUSIONS: In premedicated children, propofol-remifentanil combination provides adequate conditions for tracheal intubation that is comparable with succinylcholine. Hemodynamic response to laryngoscopy and tracheal intubation was controlled better in group R.

Studies on the synthesis and activity of three tripalladium complexes containing planaramine ligands.

The present study deals with the synthesis, characterization and activity against human cancer cell lines: A2780, A2780(cisR) and A2780(ZD0473R) of three tripalladium complexes, MH3, MH4 and MH5, that each have two planaramine ligands bound to the central metal ion. Cellular uptake levels, extent of DNA binding, and nature of interaction with salmon sperm and pBR322 plasmid DNA were determined for each complex. Palladium compounds are much more reactive than their corresponding platinum derivatives, which makes them therapeutically inactive but toxic. However, the results of the present study suggest that significant antitumour activity can be introduced in palladium complexes by lessening their reactivity by the introduction of sterically hindered ligands such as 2-hydroxypyridine, 3-hydroxypyridine and 4-hydroxypyridine. When bound to the central palladium ion, 4-hydroxypyridine appears to be more activating than 2-hydroxypyridine and 3-hydroxypyridine, suggesting that noncovalent interactions, such as hydrogen bonding, may also be key determinants of antitumour activity in addition to the steric effect. While cisplatin binds with DNA to form intrastrand GG adducts that causes local bending of a DNA strand, these planaramine-derived palladium complexes are expected to bind with DNA and form a number of long-range interstrand GG adducts that would cause a global change in DNA conformation, provided the tripalladium cations in MH3, MH4 and MH5 persist under physiological conditions.