Cytokine production of lung cancer cell lines: Correlation between their production and the inflammatory/immunological responses both in vivo and in vitro

Immunotherapy for lung cancers

Lung cancer is the leading cause of cancer-related deaths worldwide. Although treatment methods in surgery, irradiation, and chemotherapy have improved, prognosis remains unsatisfactory and developing new therapeutic strategies is still an urgent demand. Immunotherapy is a novel therapeutic approach wherein activated immune cells can specifically kill tumor cells by recognition of tumor-associated antigens without damage to normal cells. Several lung cancer vaccines have demonstrated prolonged survival time in phase II and phase III trials, and several clinical trials are under investigation. However, many clinical trials involving cancer vaccination with defined tumor antigens work in only a small number of patients. Cancer immunotherapy is not completely effective in eradicating tumor cells because tumor cells escape from host immune scrutiny. Understanding of the mechanism of immune evasion regulated by tumor cells is required for the development of more effective immunotherapeutic approaches against lung cancer. This paper discusses the identification of tumor antigens in lung cancer, tumor immune escape mechanisms, and clinical vaccine trials in lung cancer.

Role of the equilibrium between colon cancer and mononuclear cells in cytokine production

Patients with ulcerative colitis and Crohn's disease are at increased risk for colorectal cancer, a phenomenon assumed to be at least in part consequence of chronic inflammation. The purpose of this study was to examine whether human colon cancer cells may promote immune cells to produce cytokines, particularly those involved in inflammatory reaction. HT-29 and RKO human colon cancer cell lines were used. Human peripheral blood mononuclear cells (PBMC) were incubated for 24 h without or with cancer cells, or with supernatants derived from these cells cultured at the same conditions. TNFα, IL-1β, IL-6, IFNγ, IL-1ra and IL-10 secreted by PBMC were detected using specific ELISA kits. Interaction between colon cancer cells and PBMC induced secretion of pro- and anti-inflammatory cytokines in a dose-dependent manner. Furthermore, supernatants from increasing number of colon cancer cells caused a dose-dependent cytokine secretion. However, the production of cytokines was more pronounced when PBMC were directly exposed to tumor cells as compared to their supernatants. The results of our experimental model demonstrating an altered balance between pro- and anti-inflammatory cytokines generated by interaction between colon cancer and immune cells support the role of the malignant cells in promoting inflammation as one of the mechanisms for progression of colon cancer.

COX-2 inhibition improves immunotherapy and is associated with decreased numbers of myeloid-derived suppressor cells in mesothelioma. Celecoxib influences MDSC function

Background

Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immature cells that accumulates in tumour-bearing hosts. These cells are induced by tumour-derived factors (e.g. prostaglandins) and have a critical role in immune suppression. MDSC suppress T and NK cell function via increased expression of arginase I and production of reactive oxygen species (ROS) and nitric oxide (NO). Immune suppression by MDSC was found to be one of the main factors for immunotherapy insufficiency. Here we investigate if the in vivo immunoregulatory function of MDSC can be reversed by inhibiting prostaglandin synthesis by specific COX-2 inhibition focussing on ROS production by MDSC subtypes. In addition, we determined if dietary celecoxib treatment leads to refinement of immunotherapeutic strategies.

Methods

MDSC numbers and function were analysed during tumour progression in a murine model for mesothelioma. Mice were inoculated with mesothelioma tumour cells and treated with cyclooxygenase-2 (COX-2) inhibitor celecoxib, either as single agent or in combination with dendritic cell-based immunotherapy.

Results

We found that large numbers of infiltrating MDSC co-localise with COX-2 expression in those areas where tumour growth takes place. Celecoxib reduced prostaglandin E2 levels in vitro and in vivo. Treatment of tumour-bearing mice with dietary celecoxib prevented the local and systemic expansion of all MDSC subtypes. The function of MDSC was impaired as was noticed by reduced levels of ROS and NO and reversal of T cell tolerance; resulting in refinement of immunotherapy.

Conclusions

We conclude that celecoxib is a powerful tool to improve dendritic cell-based immunotherapy and is associated with a reduction in the numbers and suppressive function of MDSC. These data suggest that immunotherapy approaches benefit from simultaneously blocking cyclooxygenase-2 activity.

Cytokines and growth factors stimulate hyaluronan production: role of hyaluronan in epithelial to mesenchymal-like transition in non-small cell lung cancer

In this study, we investigated the role of hyaluronan (HA) in non-small cell lung cancer (NSCLC) since close association between HA level and malignancy has been reported. HA is an abundant extracellular matrix component and its synthesis is regulated by growth factors and cytokines that include epidermal growth factor (EGF) and interleukin-1β (IL-1β). We showed that treatment with recombinant EGF and IL-1β, alone or in combination with TGF-β, was able to stimulate HA production in lung adenocarcinoma cell line A549. TGF-β/IL-1β treatment induced epithelial to mesenchymal-like phenotype transition (EMT), changing cell morphology and expression of vimentin and E-cadherin. We also overexpressed hyaluronan synthase-3 (HAS3) in epithelial lung adenocarcinoma cell line H358, resulting in induced HA expression, EMT phenotype, enhanced MMP9 and MMP2 activities and increased invasion. Furthermore, adding exogenous HA to A549 cells and inducing HA H358 cells resulted in increased resistance to epidermal growth factor receptor (EGFR) inhibitor, Iressa. Together, these results suggest that elevated HA production is able to induce EMT and increase resistance to Iressa in NSCLC. Therefore, regulation of HA level in NSCLC may be a new target for therapeutic intervention.

Knockout of the tumor suppressor gene Gprc5a in mice leads to NF-kappaB activation in airway epithelium and promotes lung inflammation and tumorigenesis

Mouse models can be useful for increasing the understanding of lung tumorigenesis and assessing the potential of chemopreventive agents. We explored the role of inflammation in lung tumor development in mice with knockout of the tumor suppressor Gprc5a. Examination of normal lung tissue and tumors from 51 Gprc5a(+/+) (adenoma incidence, 9.8%; adenocarcinoma, 0%) and 38 Gprc5a(-/-) mice (adenoma, 63%; adenocarcinoma, 21%) revealed macrophage infiltration into lungs of 45% of the Gprc5a(-/-) mice and 8% of Gprc5a(+/+) mice and the direct association of macrophages with 42% of adenomas and 88% of adenocarcinomas in the knockout mice. Gprc5a(-/-) mouse lungs contained higher constitutive levels of proinflammatory cytokines and chemokines and were more sensitive than lungs of Gprc5a(+/+) mice to stimulation of NF-kappaB activation by lipopolysaccharide in vivo. Studies with epithelial cells cultured from tracheas of Gprc5a(-/-) and Gprc5a(+/+) mice revealed that Gprc5a loss is associated with increased cell proliferation, resistance to cell death in suspension, and increased basal, tumor necrosis factor alpha-induced, and lipopolysaccharide-induced NF-kappaB activation, which were reversed partially in Gprc5a(-/-) adenocarcinoma cells by reexpression of Gprc5a. Compared with Gprc5a(+/+) cells, the Gprc5a(-/-) cells produced higher levels of chemokines and cytokines and their conditioned medium induced more extensive macrophage migration. Silencing Gprc5a and the p65 subunit of NF-kappaB in Gprc5a(+/+) and Gprc5a(-/-) cells, respectively, reversed these effects. Thus, Gprc5a loss enhances NF-kappaB activation in lung epithelial cells, leading to increased autocrine and paracrine interactions, cell autonomy, and enhanced inflammation, which may synergize in the creation of a tumor-promoting microenvironment.

Clotting, immune system, and venous thrombosis in lung adenocarcinoma patients: a prospective study

Thrombosis is highly prevalent in cancer patients, being accepted as a bad prognosis marker. The importance of various mechanisms involved in the thrombophilic state of lung cancer patients is not well understood. In this prospective study, involving 109 unselected patients with lung adenocarcinoma, thrombosis was present in 24% of patients and affected survival in a bivariable model. However, in a multivariable evaluation, considering all the factors under study, only LAC and IgM anti-beta(2) GP I modified thrombosis risk, whereas in a Kaplan-Meyer regression model, thrombosis, IL-6, LAC, factor VIII, and IgM anti-beta(2) GP I interfered with patient's survival.

Amplification of lipopolysaccharide-induced cytokine synthesis in non-small cell lung cancer/neutrophil cocultures

Proinflammatory cytokines are centrally involved in tumor progression and survival in non-small cell lung cancer, and both the presence of infiltrating neutrophils and bacterial infection in the lung may indicate a poor prognosis. Against this background, we investigated the effect of the bacterial cell wall component lipopolysaccharide (LPS) on interleukin (IL)-6 and IL-8 synthesis in the non-small cell lung cancer line A549 and in A549-neutrophil cocultures. The LPS induced a dose-dependent and time-dependent release of IL-8 from A549 cells, whereas IL-6 could not be detected. Interestingly, in A549-neutrophil cocultures, IL-8 synthesis was massively amplified and IL-6 was also released, compared with the respective monocultures. The A549 cells were identified as the primary cellular source of these cytokines, as enhanced cytokine mRNA transcription was detected in this cell type, although not in neutrophils in the coculture system. Experiments done in transwells indicated that direct cell-cell contact was a prerequisite for the increased cytokine generation. Inhibition of tumor necrosis factor-alpha bioactivity by neutralizing antibodies and blocking cyclooxygenase-2 activity blunted the enhanced cytokine generation in the coculture system. Amplification of LPS-induced cytokine secretion could be reproduced when the small cell lung cancer cell line H69 was cocultured with neutrophils. When the Gram-positive cell wall component lipoteichoic acid was used instead of LPS, cytokine synthesis was also amplified in A549-neutrophil cocultures, to a similar extent to that observed with LPS. These data indicate that interaction between bacterial pathogens, neutrophils, and tumor cells might amplify the release of proinflammatory cytokines which may promote tumor growth in vivo.

Serum concentrations of cytokines and lung cancer survival in African Americans and Caucasians

Accumulating evidence suggests a role for inflammation in the development and progression of cancer. Our group recently identified a cytokine gene signature in lung tissue associated with lung cancer prognosis. Therefore, we hypothesized that concentrations of circulating cytokines in serum may be associated with lung cancer survival. Ten serum cytokines, namely, interleukin (IL)-1beta, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, granulocyte macrophage colony-stimulating factor, interferon (IFN)-gamma, and tumor necrosis factor-alpha, were assessed in 353 non-small cell lung cancer cases from a case-control study of lung cancer in the greater Baltimore, Maryland area. Cytokines were measured using an ultrasensitive electrochemiluminescence immunoassay. IL-6 serum concentrations (>or=4.0 pg/mL) were associated with significantly poorer survival in both African Americans [hazard ratio (HR), 2.71; 95% confidence interval (CI), 1.26-5.80] and Caucasians (HR, 1.71; 95% CI, 1.22-2.40). IL-10 (HR, 2.62; 95% CI, 1.33-5.15) and IL-12 (HR, 1.98; 95% CI, 1.14-3.44) were associated with lung cancer survival only in African Americans. Some evidence for an association of tumor necrosis factor-alpha levels with survival in Caucasians was observed, although these results were not significant. These hypothesis-generating findings indicate that selected serum cytokine concentrations are associated with lung cancer survival, and indicate that further research is warranted to better understand the mechanistic underpinnings of these associations.

Regulated expression of a tumor-associated antigen reveals multiple levels of T-cell tolerance in a mouse model of lung cancer

Maximizing the potential of cancer immunotherapy requires model systems that closely recapitulate human disease to study T-cell responses to tumor antigens and to test immunotherapeutic strategies. We have created a new system that is compatible with Cre-LoxP-regulatable mouse cancer models in which the SIY antigen is specifically overexpressed in tumors, mimicking clinically relevant TAAs. To show the utility of this system, we have characterized SIY-reactive T cells in the context of lung adenocarcinoma, revealing multiple levels of antigen-specific T-cell tolerance that serve to limit an effective antitumor response. Thymic deletion reduced the number of SIY-reactive T cells present in the animals. When potentially self-reactive T cells in the periphery were activated, they were efficiently eliminated. Inhibition of apoptosis resulted in more persistent self-reactive T cells, but these cells became anergic to antigen stimulation. Finally, in the presence of tumors overexpressing SIY, SIY-specific T cells required a higher level of costimulation to achieve functional activation. This system represents a valuable tool in which to explore sources contributing to T-cell tolerance of cancer and to test therapies aimed at overcoming this tolerance.

[Production of cytokines by peripheral blood mononuclear cells--correlation with clinicomorphological features in laryngeal carcinoma]

INTRODUCTION

In studied analyzed role of the cytokines in pathology of neoplasms of various origin the importance of these proteins in regulation of immunocompetent cells function has been described. The aim of this study was to estimate of cho sen cytokines concentration produced by peripheral blood mononuclear cells and in whole blood in patients with laryngeal carcinoma and to analyze the connection of cytokines profile with clinicopathological features. MATERIALA AND METHODS: 55 patients with squamous cell carcinoma of the larynx treated at ENT Department Medical University of Lodz between 2003-2007 were analyzed. For estimation of cytokine secretion the cultures of isolated peripheral blood mononuclear cells (T lymphocytes) and the whole blood were established. Production of cytokines in supernatants was detected by Elisa. Connections with clinicomorphological features (pT, pN, Anneroth, Batsakis i Lunas' classification) were analyzed.

RESULTS

Authors reported statistical correlation between chosen cytokines concentration and clinicomorphological parameters: pT and IL-2, IL-6, IL-8, TNFalpha produced by isolated cells and IL-2, IL-6, TNFa and IFNgamma in whole blood, pN and IL-8, IL-10, IFNgamma; ABL score and IL-6, TNFalpha, IFNgamma produced by isolated cells and IL-2, IL-6, IL-10, TNFalpha, IFNgamma in whole blood.

CONCLUSION

Our studied indicated the important influence of proinflammatory and regulatory cytokines produced by immunocompetent cells for course of neoplasm disease, aggressiveness and advance in laryngeal carcinoma.

[Production of proinflammatory cytokines IL-6 and IL-8 by peripheral blood lymphocytes T under influence in vitro of squamous cell carcinoma of the larynx]

AIM

The most important mechanism of host humoral immunity in antitumor response is cytokines activity produced by T lymphocytes. The aim of this preliminary study was estimation of IL-6 and IL-8 serum concentration in patients with squamous cell laryngeal carcinoma and analysis of indirect influence of neoplasm cells to the function of T lymphocytes and modification of proinflammatory cytokines profile.

MATERIALS AND METHODS

7 patients with squamous cell carcinoma of the larynx treated at ENT Department Medical University of Lodź between 2003-2005 were analyzed. For estimation of proinflammatory cytokine secretion the cocultures of isolated peripheral blood lymphocytes, centrum and margin neoplasm cells and noncancerous cells were established. Production of cytokines in supernatants was detected by Elisa.

RESULTS

Authors reported that in vitro epithelial cells of the larynx is able to secrete of IL-8, but not IL-6. The presence of normal epithelial cells and carcinoma cells in lymphocyte culture may increase concentration of IL-6 and IL-8 especially with normal laryngeal epithelium cells.

CONCLUSION

Laryngeal squamous carcinoma cells could modified T lymphocytes activity and production of proinflammatory cytokines IL-6 and IL-8.

Lack and restoration of sensitivity of lung cancer cells to cellular attack with special reference to expression of human leukocyte antigen class I and/or major histocompatibility complex class I chain related molecules A/B

Both cytotoxic T lymphocytes (CTL) and natural killer (NK) cells may play major roles in the host defense against cancer. However, their relationship against the same tumor remains to be elucidated. Among 26 human lung cancer cell lines established in our laboratory, 10 (38%) exhibited human leukocyte antigen (HLA)-class I haplotype loss and three (12%) lost HLA-class I expression totally by flow cytometry analysis. The two cell lines (E522L and C831L) that lost their expression of HLA-class I in vitro and in vivo were applied for further evaluations. Genetic abnormalities of beta2-microglobulin gene were observed in both E522L (loss of mRNA) and C831L (point mutation). Transduction of the wild-type beta2-microglobulin gene rendered them positive for HLA-class I expression. The CTL were induced from autologous peripheral blood mononuclear cells or regional lymph node lymphocytes by stimulation with wild-type beta2-microglobulin transduced-E522L or -C831L, and they showed tumor-specific cytotoxicity against wild-type beta2-microglobulin-transductant, but not parental cells. In NK cell cytotoxicity, E522L showed high sensitivity to NK cells; however, C831L showed resistance despite loss of HLA-class I expression. E522L expressed MHC class I chain related molecules A/B, but C831L did not. The transduction of the MHC class I chain related molecule A gene from E522L rendered C831L positive for expression and sensitive to NK cell cytotoxicity. Reconstruction of HLA-class I and MHC class I chain related molecules A expression could abrogate evasion from cellular attack by CTL and NK cells, and it may lead to a breakthrough in the development of cancer immunotherapy.