In vivo cytokine responses to interleukin-2 immunotherapy after autologous stem cell transplantation in children with solid tumors

Association between functional polymorphisms in IL-33/ST2 pathway and risk of osteosarcoma

Interleukin (IL)-33/ST2 pathway plays crucial roles in tumour growth and metastasis. The aim of this study was to investigate the association of two functional polymorphisms (IL-33 rs7025417 and ST2 rs3821204) with osteosarcoma (OS) risk. The rs7025417 and rs3821204 were genotyped by Taqman assay. IL-33mRNA and protein levels were measured by real-time PCR or enzyme-linked immunosorbent assay. The luciferase activity was measured by a dual luciferase reporter gene assay. The allele-specific transcription factor binding for rs7025417 was examined by ChIP-seq. The IL-33 rs7025417 CC genotype was significantly associated with a decreased risk of OS (CC vs TT: OR = 0.59, 95% CI, 0.41-0.85; recessive model: OR = 0.68, 95% CI, 0.49-0.94; C vs T: OR = 0.76, 95% CI, 0.63-0.91). Combined analysis showed that the IL-33 rs7025417CT/CC-ST2 rs3821204CG/CC and the IL-33 rs7025417CT/CC-ST2 rs3821204GG genotypes also had a decreased risk of OS. IL-33mRNA and protein levels in OS patients were significantly higher than controls. Patients with the rs7025417 CC genotype exhibited lower levels of IL-33 (P = .03). The rs7025417 C allele presented a lower transcriptional activity by disrupting the binding site to c-Myb (P < .01). Moreover, the rs3821204 G/C influences the transcriptional activity and ST2mRNA expression by altering the binding site of miR-202-3p. These findings suggest that the rs7025417 and rs3821204 may have a combined effect to protect against the development of OS by decreasing the expression levels of IL-33 or ST2.

A fluorescent microbead-based microfluidic immunoassay chip for immune cell cytokine secretion quantification

Quantitative and dynamic analyses of immune cell secretory cytokines are essential for precise determination and characterization of the "immune phenotype" of patients for clinical diagnosis and treatment of immune-related diseases. Although multiple methods including the enzyme-linked immunosorbent assay (ELISA) have been applied for cytokine detection, such measurements remain very challenging in real-time, high-throughput, and high-sensitivity immune cell analysis. In this paper, we report a highly integrated microfluidic device that allows for on-chip isolation, culture, and stimulation, as well as sensitive and dynamic cytokine profiling of immune cells. Such a microfluidic sensing chip is integrated with cytometric fluorescent microbeads for real-time and multiplexed monitoring of immune cell cytokine secretion dynamics, consuming a relatively small extracted sample volume (160 nl) without interrupting the immune cell culture. Furthermore, it is integrated with a Taylor dispersion-based mixing unit in each detection chamber that shortens the immunoassay period down to less than 30 minutes. We demonstrate the profiling of multiple pro-inflammatory cytokine secretions (e.g. interleukin-6, interleukin-8, and tumor necrosis factors) of human peripheral blood mononuclear cells (PBMCs) with a sensitivity of 20 pg ml-1 and a sample volume of 160 nl per detection. Further applications of this automated, rapid, and high-throughput microfluidic immunophenotyping platform can help unleash the mechanisms of systemic immune responses, and enable efficient assessments of the pathologic immune status for clinical diagnosis and immune therapy.

Cellular immunotherapy strategies for Ewing sarcoma

Ewing sarcoma is a rare cancer of bone and soft tissues defined by a specific chromosomal rearrangement. Preclinical development of immunological treatment strategies includes expansion of T cells with native or grafted T-cell receptor specificities for Ewing sarcoma-associated intracellular antigens, and T-cell engineering with chimeric antigen receptors targeting surface antigens. In vitro preactivated NK cells may also have activity in this cancer. Major challenges are the heterogeneity of antigen expression in individual Ewing sarcomas, and the coexpression of most candidate targets on normal cells. Moreover, homing of therapeutic effector cells to both primary and metastatic tumor sites and adequate function within the immunosuppressive tumor microenvironment will have to be ensured to allow for effective immune targeting of this cancer.

Immunologic and therapeutic synergy of IL-27 and IL-2: enhancement of T cell sensitization, tumor-specific CTL reactivity and complete regression of disseminated neuroblastoma metastases in the liver and bone marrow

IL-27 exerts antitumor activity in murine orthotopic neuroblastoma, but only partial antitumor effect in disseminated disease. This study demonstrates that combined treatment with IL-2 and IL-27 induces potent antitumor activity in disseminated neuroblastoma metastasis. Complete durable tumor regression was achieved in 90% of mice bearing metastatic TBJ-IL-27 tumors treated with IL-2 compared with only 40% of mice bearing TBJ-IL-27 tumors alone and 0% of mice bearing TBJ-FLAG tumors with or without IL-2 treatment. Comparable antitumor effects were achieved by IL-27 protein produced upon hydrodynamic IL-27 plasmid DNA delivery when combined with IL-2. Although delivery of IL-27 alone, or in combination with IL-2, mediated pronounced regression of neuroblastoma metastases in the liver, combined delivery of IL-27 and IL-2 was far more effective than IL-27 alone against bone marrow metastases. Combined exposure to IL-27 produced by tumor and IL-2 synergistically enhances the generation of tumor-specific CTL reactivity. Potentiation of CTL reactivity by IL-27 occurs via mechanisms that appear to be engaged during both the initial sensitization and effector phase. Potent immunologic memory responses are generated in mice cured of their disseminated disease by combined delivery of IL-27 and IL-2, and depletion of CD8(+) ablates the antitumor efficacy of this combination. Moreover, IL-27 delivery can inhibit the expansion of CD4(+)CD25(+)Foxp3(+) regulatory and IL-17-expressing CD4(+) cells that are otherwise observed among tumor-infiltrating lymphocytes from mice treated with IL-2. These studies demonstrate that IL-27 and IL-2 synergistically induce complete tumor regression and long-term survival in mice bearing widely metastatic neuroblastoma tumors.

Feasibility of high-dose interleukin-2 in heavily pretreated pediatric cancer patients

BACKGROUND

The administration of high-dose interleukin-2 (IL-2) seems to be a therapeutic option for children with refractory and metastatic solid malignancies.

METHODS

We prospectively studied treatment-related toxicities, quality of life and laboratory parameters in 10 children with progressive or metastatic solid tumors (metastatic osteosarcoma, n=4; neuroblastoma stage IV, n=3; metastatic Ewing's sarcoma, n=2; metastatic Wilms' tumor, n=1) during IL-2 therapy. Patients were scheduled to receive five cycles of high-dose IL-2 by continuous infusion for 5 days every 3 weeks.

RESULTS

All patients developed fever >39 degrees C and influenza-like symptoms, with a significant decrease in Karnofsky score. In two patients treatment had to be stopped after three cycles because of severe side-effects. During IL-2 therapy a statistical significant increase in white blood cells (WBC), creatinine, gamma-glutamyltransferase, C-reactive protein, glucose and body weight was observed. In contrast, red blood cells, platelets, protein, albumin and cholinesterase significantly decreased. When results from day 1 of the first and of the fifth cycle were compared, an increase of WBC and a decrease of alkaline phosphatase was shown. No constant quantitative changes in total lymphocytes and subsets were observed during IL-2 therapy.

CONCLUSIONS

IL-2 treatment in children with refractory and relapsed solid malignancies is associated with severe, but reversible, side-effects. However, five of the 10 patients with diseases of worst prognosis could be rescued by this treatment.

Megatherapy and stem cell transplantation for Ewing's family of tumors: a critical review of current literature

Although a multimodal approach consisting of chemotherapy and local control with surgery and/or radiation has improved survival in children with Ewing's sarcoma family of tumors, the prognosis for patients with high-risk disease remains poor. More aggressive treatments with high-dose myeloablative chemotherapy followed by stem cell rescue have been utilized in an attempt to improve survival in these patients. Although many studies have been published, it is difficult to interpret the data since patient populations were heterogeneous with respect to disease stage, prior therapy, conditioning and stem cell source. Furthermore, there was no uniform definition of high risk, the sample sizes were small and most studies lacked appropriate control groups. Assessment of the utility of megatherapy will require prospective controlled studies.

IL-2-based immunotherapy after autologous transplantation for lymphoma and breast cancer induces immune activation and cytokine release: a phase I/II trial

We determined the safety, immune activating effects, and potential efficacy of i.v. infusion of ex vivo interleukin-2 (IL-2) activated natural killer (NK) cells (part I) or IL-2 boluses (part II) during daily s.c. IL-2 administration following hematopoietic recovery from autologous transplantation. In all, 57 patients with relapsed lymphoma (n=29) or metastatic breast cancer (n=28) were enrolled. In part I of the study, 34 patients were enrolled at three dose levels of ex vivo IL-2-activated NK cells. Lymphaphereses were performed on days 28 and 42 of s.c. IL-2 administration. Following overnight ex vivo IL-2 activation of the pheresis product, the cells were reinfused the following day. In part II, 23 patients were enrolled at three dose levels of supplemental i.v. IL-2 bolus infusions, given on days 28 and 35 during s.c. IL-2 administration. Toxicities were generally mild, and no patient required hospitalization. Lytic function was markedly enhanced for fresh peripheral blood mononuclear cells (PBMNCs) obtained 1 day postinfusion of either IL-2-activated cells or IL-2 boluses. IL-2 boluses transiently increased the levels of IL-6, IFN-gamma, TNF-alpha and IL1-beta, with increases in IL-6 and IFN-gamma being dose dependent. A total of 37 patients (19 patients with lymphoma, 18 with breast cancer) treated with an optimum dose of post-transplant immunotherapy (defined as having received 1.75 x 10(6) IU/m(2)/day of s.c. IL-2 plus at least one of the planned ex vivo IL-2-activated cell infusions/IL-2 boluses) could be matched with controls from the Autologous Blood and Marrow Transplant Registry database. The matched-pairs analysis demonstrated no improvement in disease outcomes of survival and relapse. We conclude that IL-2-activated cells/IL-2 boluses can be safely administered, generate PBMNCs with enhanced cytotoxicity against NK-resistant targets, and increase cytokine levels. With this dose and schedule of administration of IL-2, no improvement in patient disease outcomes was noted. Alternative strategies will be needed to exploit the immunotherapeutic potential of IL-2-activated NK cells.

Co-operation of IL-1 and IL-2 on T-cell activation in mononuclear cell cultures

In search of an optimized anti-cancer immunotherapy, the combination of IL-2 and IL-1 has been tried. In an in-vitro LAK model, this cytokine cocktail seemed to be quite promising. In our in-vitro model of IL-2 induced T-cell activation we have therefore investigated the co-operation of these two potent immunostimulators. Mononuclear cells were stimulated with CD3 activating antibody in the presence of different cytokines and blocking or neutralizing antibodies. Cytokine concentrations were detected in the supernatants with ELISA. Intracellular IFN-gamma and IL-4 in the different T-cell subsets was measured by flow cytometry. IL-1 and IL-1 receptor antagonist (IL-1Ra) were up-regulated by IL-2, this was achieved independently of IL-12 or CD40/CD40L interaction. As a negative feedback mechanism, IL-1beta induced its natural antagonist, IL-1Ra. Both endogenous and exogenous IL-10 suppressed IL-1beta and induced IL-1Ra, thus markedly decreased the amount of functional IL-1. The combination of IL-2 and IL-1beta lead to a mildly increased Interferon-gamma (IFN-gamma) secretion (+20%, p < 0.05), however, this appeared to be the result of an increased IFN-gamma production per secreting cell, rather than of an increased recruitment of non-secreting cells. Similarly, IL-6 was also induced in an additive fashion (+30%, p < 0.05). For both cytokines, this effect could be significantly augmented by neutralizing IL-1Ra. Concentrations of IL-2 induced IL-10 and soluble Fas ligand (sFasL) were not affected by IL-1beta. We were thus able to demonstrate that IL-1 relays its activity through different pathways than IL-2. Furthermore, we could show that the potentially synergistic action of IL-2 and IL-1 was hindered by the simultaneous induction of signficant amounts of IL-1Ra. From the latter findings we conclude that the combination of IL-2 and IL-1 for cytokine-induced anti-tumor activity may not, but a combination of IL-2 and anti-IL-1Ra might prove beneficial.