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Introduction: Nasopharyngeal carcinoma (NPC) is a major public health problem in several countries, especially those in Southeast Asia and North Africa. In its typical poorly differentiated form, the Epstein-Barr virus (EBV) genome is present in the nuclei of all malignant cells with restricted expression of a few viral genes. The malignant phenotype of NPC cells results from the influence of these viral products in combination with cellular genetic, epigenetic and functional alterations. With regard to host/tumor interactions, NPC is a remarkable example of immune escape in the context of a hot tumor.Areas covered: This article has an emphasis on emerging therapeutic targets that are considered upstream or at an early stage of clinical application. It examines targets related to cellular oncogenic alterations, latent EBV infection and tumor interactions with the immune system.Expert opinion: There is a remarkable emergence of new agents that target EBV products. The clinical application of these agents would benefit from a systematic and comprehensive molecular classification of NPCs and from easy access to pre-clinical models in public repositories. There is a strong rationale for more investigations on the potential of immune modulators, especially those related to NK cells.

Cancer immunology immunotherapy : CII (2020). doi:10.1007/s00262-020-02681-x, Published by Springer, Heidelberg

International audience; The combination of neoadjuvant chemotherapy, radiochemotherapy, and maintenance therapy with interferon beta (IFNβ) has led to superior results in the treatment of children and adolescents with nasopharyngeal carcinoma (NPC). However, nothing is known about the mechanism of the antitumor activity of IFNβ in NPC. Here, we investigate the role of IFNβ on apoptosis in NPC cells. Six NPC cell lines, one patient-derived NPC xenograft (PDX) and one SV40-transformed nasoepithelial cell line were used. Induction of apoptosis by IFNβ was measured by flow cytometric analysis of subG1-DNA-content, Hoechst 33258 staining and activation of caspase-3. Dissection of death ligand signaling pathways included measuring surface expression of its components by flow cytometry, activation by death ligands and neutralization with specific antibodies and siRNA. IFNβ induced apoptosis at concentrations achievable in humans in five of six NPC cell lines and in PDX cells but not in nasoepithelial cells. Inhibition of caspases-3 and-8 abrogated this effect suggesting IFNβ promoted apoptosis through the extrinsic pathway. IFNβ induced surface expression of TRAIL and TRAIL-R2 and the addition of an anti-TRAIL-antibody or transfection with TRAIL-siRNA blocked IFNβ-induced apoptosis. No induction of TRAIL-expression was noted in the IFNβ-resistant cell line. In conclusion, IFNβ leads to apoptosis in NPC cells in an autocrine way via the induction of TRAIL expression and subsequent activation of the TRAIL-signaling pathway. The mechanism described could at least partly explain the clinical benefit of IFNβ in the treatment of NPC. Further studies in a mouse-xenograft model are warranted to substantiate this effect in vivo.

Cells : open access journal 10(9), 2458 (2021). doi:10.3390/cells10092458 special issue: "Special issue "Regulation of natural killer cell development and functions" / special issue editors: Subramaniam Malarkannan, guest editor; Anahid Jewett, guest editor", Published by MDPI, Basel

Nasopharyngeal carcinoma (NPC) is an EBV-associated neoplasm occurring endemically in Southeast Asia and sporadically all over the world. In children and adolescents, high cure rates have been obtained using chemotherapy, radiochemotherapy and maintenance therapy with interferon beta (IFNβ). The mechanism by which IFNβ contributes to a low systemic relapse rate has not yet been fully revealed. NK cells and serum samples from two patients with NPC were analyzed before and at different time points during IFNβ therapy, for assessment of TRAIL expression and NK cell cytotoxicity. Cytotoxicity was measured using the calcein release assay and the contribution of different death effector pathways was analyzed using specific inhibitors. Treatment with IFNβ induced TRAIL expression on patients’ NK cells and increased their cytotoxicity against NPC targets in vitro. NK cell-mediated cytotoxicity was predominately mediated via TRAIL. IFNβ also induced the production of soluble TRAIL (sTRAIL) by NK cells and its release upon contact with NPC cells. IFNβ treatment increased serum levels of sTRAIL in patients. Moreover, sTRAIL concentrated from patients’ serum samples induced apoptosis ex vivo in NPC cells from a patient-derived xenograft. Increased cytotoxicity of NK cells against NPC cells and increased serum levels of biologically active TRAIL in patients treated with IFNβ could be a means to eliminate micrometastatic disease and explain the low systemic relapse rate in this patient group.

PLoS one 11(11), e0166766 (2016). doi:10.1371/journal.pone.0166766, Published by PLoS, Lawrence, Kan.

Guillain-Barré syndrome (GBS) is a monophasic inflammatory disease considered to be due to autoimmunity. In order to test the hypothesis that the disease is associated with a perturbation of the circulating lymphoid cell population, we tested the mononuclear cells from the venous blood of 21 patients with Guillain-Barré syndrome (GBS) and 20 healthy controls by flow cytometry. The proportions and numbers of B and T lymphocytes, and CD4, CD8, double negative and gammadelta T cell subsets and numbers of monocytes were not significantly different in the patients compared with the controls. However, the number and proportion of CD4+CD25+ cells were reduced in acute GBS (mean number 61.7 cells/microl, 95% CI 42.9-80.4 and mean percentage 4.6%, 95% CI 3.8-5.4) compared with controls (mean number 99.8 cells/microl, 95% CI 74.7-124.9, p=0.02, and mean percentage 6.0%, 95% CI 4.9-7.1%, p=0.037). In addition, in GBS patients, the number and proportion of CD4+ T cells expressing CD25+ and HLA-DP, DQ, DR (mean number 11.9 cells/microl, 95% CI 7.6-16.1 and mean percentage 0.8%, 95% CI 0.5-1.1%) was lower than in healthy controls (23.5 cells/microl, 95% CI 16.4-30.6, p=0.01, and mean percentage 1.4%, 95% CI 1.1-1.8%, p=0.005. Since CD4+CD25+ cells include cells with special immunoregulatory functions, further investigation of this phenomenon and its relation to possible loss of regulatory T cell function in GBS is warranted.

BMC cancer 15(1), 552 (2015). doi:10.1186/s12885-015-1564-7, Published by BioMed Central, London

Introduction: Upregulation of phosphodiesterase 4 (PDE4) activity causes cAMP-dependent vascular smooth muscle cell (VSMC) activation at sites of vascular inflammation and tissue remodeling. Hypothesis: PDE4 inhibition reduces VSMC activation and neointima formation following vascular injury. Methods: C57BL/6 mice (n=16) treated with roflumilast underwent guide wire-induced endothelial denudation injury of the femoral artery. Neointima formation was quantified after 4 weeks. In vitro, we analyzed the effects of roflumilast on VSMC proliferation and inflammation. Results: Roflumilast treatment attenuated neointima formation by 40% (17252 ± 2315 vs. 10119 ± 738 μm 2 , p=0,02) and femoral artery intima-media ratio by more than 50% (2,76 ± 0,32 vs. 1,35 ± 0,25 ,p=0,005). In vitro, roflumilast did not affect VSMC proliferation, but diminished TNF-α induced expression of the inflammatory marker vascular cell adhesion molecule 1 (VCAM-1) by 60% (p Conclusions: PDE4 inhibtion reduces neointimal hyperplasia after vascular injury and regulates VCAM-1 through a novel Epac-dependent mechanism, which modulates specific histone methylation patterns. PDE4 inhibition might represent a novel approach for the treatment of vascular diseases, including atherosclerosis and in-stent restenosis.

NKT cells are associated with immunological control of autoimmune disease and cancer and can recognize cell surface mCD1d without addition of exogenous antigens. Cellular antigens presented by mCD1d have not been identified, although NKT cells can recognize a synthetic glycolipid, alpha-GalCer. Here we show that after addition of a lipid extract from a tumor cell line, plate-bound mCD1d molecules stimulated an NKT cell hybridoma. This hybridoma also responded strongly to three purified phospholipids, but failed to recognize alpha-GalCer. Seven of sixteen other mCD1d restricted hybridomas also showed a response to certain purified phospholipids. These findings suggest NKT cells can recognize cellular antigens distinct from alpha-GalCer and identify phospholipids as potential self-antigens presented by mCD1d.

Background: Potential target autoantigens in the demyelinating form of Guillain–Barre syndrome (GBS) include the myelin proteins PMP22, P0 and P2. Methods: We investigated immunoreactivity to P0, P2 and PMP22 proteins in 37 patients with GBS and 32 healthy controls. Results: Antibodies to PMP22 or P0 peptides were detected at presentation in only 5 out of 37 patients. In ELISPOT assays, blood mononuclear cells from 15 out of 24 patients with GBS, but none of the control subjects, produced interleukin-10 (IL-10) in response to peptides from proteins P0, P2 or PMP22 (p = 0.0003). The cells from only two patients produced interferon-γ (IFNγ). The cells from 11 patients with GBS had increased IL-10 responses to peptides representing sequences from the extracellular domains of PMP22 before intravenous immunoglobulin (IVIg) treatment (p = 0.006). The cells from 11 patients with GBS, including 7 who responded to the extracellular domains of PMP22, had increased IL-10 responses to the intracellular domain of P0 before (p = 0.005) and those from 9 patients after they had been treated with IVIg (p = 0.01). Conclusions: Antibodies to P0 and PMP22 protein peptides do occur in GBS but are uncommon. Circulating mononuclear cell IFNγ responses to P0, P2 and PMP22 myelin protein peptides are rare, but IL-10 responses occur significantly more often than in normal subjects. They might be part of a harmful pathogenetic process or represent a regulatory response.

The acute lesions of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) consist of endoneurial foci of chemokine and chemokine receptor expression and T cell and macrophage activation. The myelin protein antigens, P2, P0, and PMP22, each induce experimental autoimmune neuritis in rodent models and might be autoantigens in CIDP. The strongest evidence incriminates P0, to which antibodies have been found in 20% of cases. Failure of regulatory T-cell mechanism is thought to underlie persistent or recurrent disease, differentiating CIDP from the acute inflammatory demyelinating polyradiculoneuropathy form of Guillain-Barre syndrome. Corticosteroids, intravenous immunoglobulin and plasma exchange each provide short term benefit but the possible long-term benefits of immunosuppressive drugs have yet to be confirmed in randomised, controlled trials.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an acquired disorder of the peripheral nervous system with a probable auto-immune pathogenesis. The nature of the responsible autoantigens is unclear in most patients. We used the Western immunoblot technique to seek antibodies to peripheral nerve protein antigens. Sera from eight of 32 (25%) CIDP patients, 12 of 37 (32%) Guillain-Barre syndrome (GBS) patients, zero of 30 (0%) chronic idiopathic axonal polyneuropathy patients and two of 39 (5%) healthy control subjects contained anti-peripheral nerve protein antibodies. The frequency of such antibodies was significantly greater in both CIDP (p = 0.04) and GBS (p = 0.003) patients than in normal control subjects. For CIDP patients, there were non-significant trends for antibodies to be more common in females and in those who responded to treatment with either intravenous immunoglobulin or plasma exchange. The commonest antibodies were directed against a band at 28 kDa, resembling that labelled by a monoclonal antibody against myelin protein zero (P0). Six CIDP and seven GBS patients' sera reacted with this band. These results support the view that antibodies to myelin proteins, and especially P0, are present in the serum of some patients with CIDP and GBS.

Nociceptive input from neck muscles probably plays a role in the pathophysiology of tension-type headache. In order to elaborate an animal model, the impact of noxious input from neck muscles on orofacial sensorimotor processing was investigated by electrophysiological means in anesthetized mice. Group IV muscle afferents of the semispinal neck muscle were excited by local injection of nerve growth factor (NGF, 0.8 microM, 20 microl). Orofacial sensorimotor processing was monitored by the jaw-opening reflex (JOR) elicited by electric tongue stimulation. After unilateral NGF injection into the right neck muscle (n = 10), JOR integral (+89%) and duration (+9%) increased and latency decreased (-5%) for at least 1 h. Bilateral injection of NGF (n = 10) into neck muscles induced an increase of JOR integral (+111%) and duration (+20%) and a reduction of latency (-9%). This facilitation of the JOR lasted for at least 90 min without any downward drift (n = 5). Electric JOR threshold diminished after NGF injection. After intramuscular injection of isotonic saline into the right semispinal neck muscle (20 microl), the JOR remained unchanged (n = 10). Local NGF injection into neck muscles evoked noxious input to the brainstem that induced a sustained central facilitation of the JOR for more than 1 h. This long-term facilitation of orofacial sensorimotor processing by a singular NGF injection possibly reflects plastic changes of nociceptive synaptic processing that may be involved in the pathophysiology of headache.

PLoS one 9(3), e92115 (2014). doi:10.1371/journal.pone.0092115, Published by PLoS [u.a.], Lawrence, Kan.