Phase I Study of Multiple Epitope Peptide Vaccination in Patients With Recurrent or Persistent Cervical Cancer

Cancer immunotherapy has now been established as a leading standard therapeutic option in a subset of patients with cancer. In this study, we conducted a phase I dose-escalation trial using a mixture of 5 peptides to vaccinate cervical cancer patients with HLA-A*2402. The primary endpoints were safety and determination of a recommended vaccine dose, and the secondary endpoints were evaluations of immunologic responses and clinical efficacy. All patients had recurrent or persistent disease and had failed to respond to or were intolerant to prior standard chemotherapy. Peptides derived from forkhead box protein M1 (FOXM1), maternal embryonic leucine zipper kinase (MELK), Holliday junction-recognition protein, and vascular endothelial growth factor receptors 1 and 2 were administered to 9 patients in a 3 patient-cohort design, with doses of 0.5, 1, or 2 mg of each of the individual peptides in a mixture with incomplete Freund's adjuvant. The major adverse events were anemia and injection site reactions, which were seen in 77.8% (7/9) and 66.7% (6/9) of patients, respectively. Grade 3 anemia was observed in 1 patient. No dose-limiting toxicity of the vaccine was observed. Seven (78%) patients achieved stable disease, and the median progression-free survival was 3.3 months (102 d). Interferon-γ enzyme-linked immunospot assays for each of the 5 antigens showed that 8 (89%) and 7 (78%) patients had high T-cell responses to FOXM1 and MELK, respectively. In conclusion, we demonstrated that this 5-peptide vaccine was tolerable, and that FOXM1 and MELK could be promising targets for immunotherapy in patients with cervical cancer.

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Anti-IL-10–mediated Enhancement of Antitumor Efficacy of a Dendritic Cell–targeting MIP3α-gp100 Vaccine in the B16F10 Mouse Melanoma Model Is Dependent on Type I Interferons

The chemokine MIP3α (CCL20) binds to CCR6 on immature dendritic cells. Vaccines fusing MIP3α to gp100 have been shown to be effective in therapeutically reducing melanoma tumor burden and prolonging survival in a mouse model. Other studies have provided evidence that interleukin-10 (IL-10) neutralizing antibodies (αIL-10) enhance immunologic melanoma therapies by modulating the tolerogenic tumor microenvironment. In the current study, we have utilized the B16F10 syngeneic mouse melanoma model to demonstrate for the first time that a therapy neutralizing IL-10 enhances the antitumor efficacy of a MIP3α-gp100 DNA vaccine, leading to significantly smaller tumors, slower growing tumors, and overall increases in mouse survival. The additive effects of αIL-10 were not shown to be correlated to vaccine-specific tumor-infiltrating lymphocytes (TILs), total TILs, or regulatory T cells. However, we discovered an upregulation of IFNα-4 transcripts in tumors and a correlation of increased plasmacytoid dendritic cell numbers with reduced tumor burden in αIL-10–treated mice. Interferon α receptor knockout (IFNαR1−/−) mice received no benefit from αIL-10 treatment, demonstrating that the additional therapeutic value of αIL-10 is primarily mediated by type I IFNs. Efficient targeting of antigen to immature dendritic cells with a chemokine-fusion vaccine provides an effective anticancer therapeutic. Combining this approach with an IL-10 neutralizing antibody therapy enhances the antitumor efficacy of the therapy in a manner dependent upon the activity of type I IFNs. This combination of a vaccine and immunomodulatory agent provides direction for future optimization of a novel cancer vaccine therapy.

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Natural Compounds as Epigenetic Regulators of Human Dendritic Cell-mediated Immune Function

Dendritic cells (DCs) are the most potent professional antigen-presenting cells (APCs) and are poised to capture antigen, migrate to draining lymphoid organs, and postmaturation process. Recent evidences have suggested that tumor microenvironment has an effect on DCs by inactivating various components of the immune system responsible for tumor clearance, eventually leading to tumorigenesis. This inactivation is owed to the epigenetic modifications [ie, microRNA (miRNA)] at the posttranscriptional level, thus regulating the differentiation patterns and functional behavior of DCs. Thus, need of the hour is to develop protocols for ex vivo generation of DCs which may provide a foundation for designing and developing DC-based vaccination for treatment of solid tumors. To achieve this, it is crucial to modulate DCs by identifying miRNAs which may increase the efficacy of DC-based vaccines by reprogramming the immunosuppressive nature of tumor microenvironment. Furthermore, it would be an interesting aspect to check the immunomodulatory potential of natural compounds in reprogramming the immune responses through DCs. Thus, this review aims to improvise the understanding of DC immune biology and miRNAs at genetic level in cancer which can be pivotal for designing novel or improved therapeutic approaches that will allow proper functioning of DCs in patient care. Furthermore, we have highlighted the candidate target molecules and signaling mechanisms having a vital role in the immune-modulatory activities of natural compounds and its derived phytocompounds. This review also establishes a link between miRNA expressions and biological roles of natural compounds modulating the activity of DCs.

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In Vitro Killing of Colorectal Carcinoma Cells by Autologous Activated NK Cells is Boosted by Anti-Epidermal Growth Factor Receptor-induced ADCC Regardless of RAS Mutation Status

Treatment of advanced metastatic colorectal cancer (mCRC) patients is associated with a poor prognosis and significant morbidity. Moreover, targeted therapies such as anti-epidermal growth factor receptor (EGFR) have no effect in metastatic patients with tumors harboring a mutation in the RAS gene. The failure of conventional treatment to improve outcomes in mCRC patients has prompted the development of adoptive immunotherapy approaches including natural killer (NK)-based therapies. In this study, after confirmation that patients' NK cells were not impaired in their cytotoxic activity, evaluated against long-term tumor cell lines, we evaluated their interactions with autologous mCRC cells. Molecular and phenotypical evaluation of mCRC cells, expanded in vitro from liver metastasis, showed that they expressed high levels of polio virus receptor and Nectin-2, whereas UL16-binding proteins were less expressed in all tumor samples evaluated. Two different patterns of MICA/B and HLA class I expression on the membrane of mCRC were documented; approximately half of mCRC patients expressed high levels of these molecules on the membrane surface, whereas, in the remaining, very low levels were documented. Resting NK cells were unable to display sizeable levels of cytotoxic activity against mCRC cells, whereas their cytotoxic activity was enhanced after overnight or 5-day incubation with IL-2 or IL-15. The susceptibility of NK-mediated mCRC lysis was further significantly enhanced after coating with cetuximab, irrespective of their RAS mutation and HLA class I expression. These data open perspectives for combined NK-based immunotherapy with anti-epidermal growth factor receptor antibodies in a cohort of mCRC patients with a poor prognosis refractory to conventional therapies.

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PD-1 Inhibitor-associated Myopathies: Emerging Immune-mediated Myopathies

Programmed death-1 (PD-1) inhibitors are increasingly used in cancer immunotherapy. Various immune-related adverse events are reported, including infrequent individual case reports of myositis or rhabdomyolysis. The frequency and diagnostic spectrum of immune-related adverse events affecting skeletal muscle in PD-1 inhibitor-treated patients are unknown. We searched the Mayo Clinic Pharmacy database (2014–2016) to identify patients who developed myopathies during or after PD-1 inhibitor therapy. Among 654 cancer patients received PD-1 inhibitors (pembrolizumab=389; nivolumab=264; both=1), we identified 5 patients (pembrolizumab=5) with biopsy-proven myopathies (2 necrotizing myopathy, 1 early dermatomyositis, and 2 nonspecific myopathy). Four patients developed concomitant autoimmune disorders. Weakness occurred after a median of 2 treatments (range, 1–4). All patients had proximal or axial weakness. Four patients had either bulbar or extraocular weakness, but only 1 patient had acetylcholine receptor antibodies. Creatine kinase levels were elevated in 3 patients (necrotizing myopathy=2; nonspecific myopathy=1). Brain magnetic resonance imaging revealed abnormal T2 signal and enhancement of extraocular muscles in 1 patient with ophthalmoparesis. Pembrolizumab was discontinued in all patients. All patients received immunosuppressive therapy, with fatal outcome in 2 necrotizing myopathy patients and favorable outcome in others. We conclude that myopathy is a rare, but unique complication of PD-1 inhibitors with frequent involvement of extraocular or bulbar muscles, mimicking myasthenia gravis. Muscle biopsy is an important test for PD-1 inhibitor-treated patients who develop oculobulbar weakness and hyperCKemia, to distinguish patients with necrotizing myopathy from myasthenia gravis. Necrotizing myopathy patients may require more aggressive immunotherapy due to their grave prognosis.

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In Response

No abstract available

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Differential Effects of Anesthetics and Opioid Receptor Activation on Cardioprotection Elicited by Reactive Oxygen Species–Mediated Postconditioning in Sprague-Dawley Rat Hearts

BACKGROUND: Despite an array of cardioprotective interventions identified in preclinical models of ischemia–reperfusion (IR) injury, successful clinical translation has not been achieved. This study investigated whether drugs routinely used in clinical anesthesia influence cardioprotective effectiveness by reducing effects of reactive oxygen species (ROS), upstream triggers of cardioprotective signaling. Effects of propofol, sevoflurane, or remifentanil were compared on postischemic functional recovery induced by ROS-mediated postconditioning with Intralipid. METHODS: Recovery of left ventricular (LV) work, an index of IR injury, was measured in isolated Sprague-Dawley rat hearts subjected to global ischemia (20 minutes) and reperfusion (30 minutes). Hearts were either untreated or were treated with postconditioning with Intralipid (1%, throughout reperfusion). Propofol (10 μM), sevoflurane (2 vol%), remifentanil (3 nM), or combinations thereof were administered peri-ischemically (before and during IR). The effects of anesthetics on ROS production were measured in LV cardiac fibers by Amplex Red assay under phosphorylating and nonphosphorylating conditions. RESULTS: Recovery of LV work (expressed as percentage of the preischemic value ± standard deviation) in untreated hearts was poor (20% ± 7%) and was improved by Intralipid postconditioning (58% ± 8%, P = .001). In the absence of Intralipid postconditioning, recovery of LV work was enhanced by propofol (28% ± 9%, P = .049), sevoflurane (49% ± 5%, P

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