Cytokine secretion: clinical relevance of immunosuppression in non-small cell lung cancer

Cytokines screening identifies MIG (CXCL9) for postoperative recurrence prediction in operated non-small cell lung cancer patients

BACKGROUND

Exploration of reliable biomarkers most likely to identify non-small cell lung cancer (NSCLC) patients at high risk for recurrence after surgery is needed.

METHODS

Quantibody® Human Cytokine Antibody 6000 was used as screening tool to measure serum levels of 280 cytokines in ten healthy individuals and nine samples from three NSCLC patients before operation, after operation and postoperative recurrence. Selected cytokines were validated in two independent sets (89 patients before surgery, 69 patients after surgery and 40 patients with postoperative recurrence for each set) using ELISA method. The association of the selected cytokine with clinicopathologic features was also evaluated.

RESULTS

Thirty-six cytokines were declined after surgery and again elevated when recurrence. We selected MIG to be further assessed in 2 validation sets, the mean value of serum MIG levels in 396 NSCLC patients was 253.42 ± 274.48 pg/mL and was significantly higher than the level in 60 healthy controls (47.65 ± 33.23 pg/mL, P < 0.0001). The serum MIG levels were 366.36 ± 324.04 pg/mL pre-operation, 134.04 ± 127.52 pg/mL post-operation and 208.05 ± 239.39 pg/mL in recurrence in NSCLC patients. The serum MIG levels were significant differences among NSCLC patients of pre-operation, post-operation and recurrence and controls (P < 0.0001). Moreover, Serum MIG levels were decreased markedly after operation and notably increased when disease relapsed (P < 0.0005). Serum MIG levels trend to be higher in patients with male gender, older age, smoking habit, poor tumor differentiation, and non-adenocarcinoma histology.

CONCLUSIONS

These data indicated that MIG might be an indicator of postoperative recurrence and help to identify NSCLC patient who was easy to relapse after surgery.

Anti-α-enolase is a prognostic marker in postoperative lung cancer patients

Our previous studies suggest that antibodies against ENO1 (anti-ENO1 Ab) have a protective role in patients with non-small cell lung carcinoma. In this study, we evaluated the prognostic value of anti-ENO1 Ab levels in non-small cell lung carcinoma patients undergoing surgery. Circulating levels of anti-ENO1 Ab were assessed in 85 non-small cell lung carcinoma patients before and after surgery, and were correlated with clinical outcome. After surgery, patients with a higher increase of anti-ENO1 Ab had a lower hazard ratio and a better progression-free survival. Using animal models, we demonstrated that tumor cells reduce the circulating levels of anti-ENO1 Ab through physical absorption and neutralization of anti-ENO1 Ab with surface-expressed and secreted ENO1, respectively. Mice transplanted with ENO1-overexpressing tumors generated ENO1-specific regulatory T cells to suppress the production of anti-ENO1 Ab. Our results suggest that the increase of anti-ENO1 Ab may reflect anti-tumor immune responses and serve as a prognostic marker in postoperative lung cancer patients.

Targeting histone deacetylase 6 mediates a dual anti-melanoma effect: Enhanced antitumor immunity and impaired cell proliferation

The median survival for metastatic melanoma is in the realm of 8-16 months and there are few therapies that offer significant improvement in overall survival. One of the recent advances in cancer treatment focuses on epigenetic modifiers to alter the survivability and immunogenicity of cancer cells. Our group and others have previously demonstrated that pan-HDAC inhibitors induce apoptosis, cell cycle arrest and changes in the immunogenicity of melanoma cells. Here we interrogated specific HDACs which may be responsible for this effect. We found that both genetic abrogation and pharmacologic inhibition of HDAC6 decreases in vitro proliferation and induces G1 arrest of melanoma cell lines without inducing apoptosis. Moreover, targeting this molecule led to an important upregulation in the expression of tumor associated antigens and MHC class I, suggesting a potential improvement in the immunogenicity of these cells. Of note, this anti-melanoma activity was operative regardless of mutational status of the cells. These effects translated into a pronounced delay of in vivo melanoma tumor growth which was, at least in part, dependent on intact immunity as evidenced by the restoration of tumor growth after CD4+ and CD8+ depletion. Given our findings, we provide the initial rationale for the further development of selective HDAC6 inhibitors as potential therapeutic anti-melanoma agents.

Lung cancer vaccines: current status and future prospects

Designing a cancer treatment that very specifically targets and kills tumor cells with little to no side effects is the "holy grail" of oncology. Cancer vaccines have this potential. Vaccines utilize the immune system to specifically target and eliminate tumor cells. Historically, vaccination approaches against lung cancer have been disappointing. However, over the past decade, a greater understanding of the immune system and of the antigens expressed by tumors, coupled with advances in immunoadjuvants and improved delivery systems, has led to advances in the use of immunotherapy including vaccines to target lung cancer. Proof of principle phase I/II clinical trials targeting the MAGE-A3 and MUC1 tumor antigens, as well as cell-based vaccines such as belagenpumatucel-L have suggested improved survival, leading to larger scale phase III clinical trials. This review will discuss cancer vaccines in relation to lung cancer and present clinical data supporting their use.

Changes in circulating immunosuppressive cytokine levels of cancer patients after high intensity focused ultrasound treatment

Immunosuppression in a patient with malignant tumor is a major obstacle in cancer treatment. In this study, we investigated changes in the circulating level of all measured immunosuppressive cytokines in patients with malignancy before and after high intensity focused ultrasound (HIFU) treatment. Fifteen patients with solid malignancy were enrolled in this study and an enzyme-linked immunoabsorbent assay (ELISA) method was used to measure serum level of vascular endothelial growth factor (VEGF), transforming growth factor-beta1 (TGF-beta1), transforming growth factor-beta2 (TGF-beta2), interleukin 6 (IL-6) and interleukin 10 (IL-10), respectively before and 1 wk after HIFU treatment. Among them, seven patients had distant metastasis and the remaining eight had no metastasis. All patients received one-session HIFU treatment for primary cancer, including complete ablation in eight patients without metastasis, and partial ablation in seven patients with metastases. The results showed that serum immunosuppressive cytokine levels decreased after HIFU treatment, and there were significant decreases of VEGF, TGF-beta1, and TGF-beta2 before and after HIFU treatment. Compared with the values in the metastatic patients, serum levels of immunosuppressive cytokines were significantly lower in the nonmetastatic patients after HIFU treatment. It is concluded that HIFU can decrease tumor-secreted immunosuppressive cytokine production in addition to its direct tumor destruction. This change may lessen tumor-induced immunosuppression and renew antitumor immunity after HIFU in cancer patients.

Inflammation and lung carcinogenesis: applying findings in prevention and treatment

Lung carcinogenesis is a complex process requiring the acquisition of genetic mutations that confer the malignant phenotype as well as epigenetic alterations that may be manipulated in the course of therapy. Inflammatory signals in the lung cancer microenvironment can promote apoptosis resistance, proliferation, invasion, metastasis, and secretion of proangiogenic and immunosuppressive factors. Here, we discuss several prototypical inflammatory mediators controlling the malignant phenotype in lung cancer. Investigation into the detailed molecular mechanisms underlying the tumor-promoting effects of inflammation in lung cancer has revealed novel potential drug targets. Cytokines, growth factors and small-molecule inflammatory mediators released in the developing tumor microenvironment pave the way for epithelial-mesenchymal transition, the shift from a polarized, epithelial phenotype to a highly motile mesenchymal phenotype that becomes dysregulated during tumor invasion. Inflammatory mediators within the tumor microenvironment are derived from neoplastic cells as well as stromal and inflammatory cells; thus, lung cancer develops in a host environment in which the deregulated inflammatory response promotes tumor progression. Inflammation-related metabolic and catabolic enzymes (prostaglandin E(2) synthase, prostaglandin I(2) synthase and 15-hydroxyprostaglandin dehydrogenase), cell-surface receptors (E-type prostaglandin receptors) and transcription factors (ZEB1, SNAIL, PPARs, STATs and NF-kappaB) are differentially expressed in lung cancer cells compared with normal lung epithelial cells and, thus, may contribute to tumor initiation and progression. These newly discovered molecular mechanisms in the pathogenesis of lung cancer provide novel opportunities for targeted therapy and prevention in lung cancer.

Effect of celecoxib and novel agent LC-1 in a hamster model of lung cancer

BACKGROUND

Lung cancer is the leading cause of cancer deaths in the United States. Inflammatory molecules, cyclooxygenase-2 (COX-2) and nuclear factor kappa B (NF-kappaB) have been implicated in lung carcinogenesis. The therapeutic potential of celecoxib, a COX-2 selective inhibitor, and LC-1, a pro-apoptotic drug with accompanying inhibition of NF-kappaB, were investigated.

MATERIALS AND METHODS

Syrian golden hamsters (n = 140) underwent N-nitroso-bis(2-oxopropyl)amine (BOP) injection weekly for 6 wk. Hamsters were randomized into seven groups: placebo and low/high doses of LC-1, celecoxib, and LC-1/celecoxib. Treatments were given via orogastric lavage for 32 wk. Immunohistochemistry was used to determine COX-2 expression and NF-kappaB activity. Ki-67 labeling was used as an index of proliferation. COX activity was measured by prostaglandin E(2) enzyme-linked immunosorbent assay.

RESULTS

BOP successfully induced lung adenocarcinoma in 63% of placebo animals. Lung tumors strongly expressed COX-2 and NF-kappaB. Prostaglandin E(2) levels were decreased in celecoxib compared with placebo groups (P < 0.05) reflecting suppression of COX activity, but no decrease in NF-kappaB was seen as measured by immunohistochemistry in the tumors. There was no significant difference in tumor size, tumor incidence, or tumor proliferation index between placebo and treatment groups.

CONCLUSIONS

Carcinogen exposure results in increased COX-2 and NF-kappaB expression and suggests a role in carcinogenesis. Celecoxib and LC-1 did not have any effect in preventing lung cancer development when co-administered with and continued after the carcinogen BOP. Higher doses that can result in suppression of NF-kappaB activity will need to be explored to determine the viability of this approach to prevent lung cancer development.

A review of vaccine clinical trials for non-small cell lung cancer

Recent evidence suggests that vaccines which enhance tumour antigen recognition may provide clinical benefit to subsets of non-small cell lung cancer patients. In this review, a variety of peptide-, gene- and cell-based clinical vaccine approaches targeting non-small cell lung cancer patients are reviewed. Results consistently demonstrate lack of toxicity. Examples of prolonged stable disease, tumour shrinkage response and survival benefit in comparison with historical and low-dose control groups have been demonstrated. Specific vaccines fulfilling justification for Phase III evaluation based on these results include LBLP25, TGF-beta2 antisense gene vaccine and GVAX.

Interleukin-2 for the treatment of solid tumors other than melanoma and renal cell carcinoma

Interleukin-2 (IL-2) is a lymphokine produced by T cells whose main function is to stimulate the growth and cytotoxic response of activated T lymphocytes. It has been used to stimulate the immune system for the treatment of multiples tumors. This article is intended to review the reports published from 1990 to 2004 on the IL-2 treatment of tumors other than melanoma and renal carcinoma. A literature search was made in various databases (MEDLINE, EMBASE and BioAssay), focused on IL-2 clinical efficacy in such tumors. A selection was made over 150 publications reporting on administration of IL-2 in multiple tumors: lung carcinoma (small cell and non-small cell), colorectal, gastric, pancreatic, ovarian and breast cancer, sarcomas, hepatocarcinoma, mesothelioma, and brain, urological, and head and neck tumors. IL-2 was mainly used in metastatic disease, associated with other immunotherapy or chemotherapy schedules. We conclude that adjuvant IL-2 may be of value in early stages combined with standard treatment for colon and pancreas cancers. In other neoplasms, the indication for adjuvant IL-2 has been sporadic and does not allow conclusions to be drawn. Assessment of the efficacy of IL-2 combined with chemotherapy as treatment for advanced stages is complex, due to the lack of a control, and the variety of dosages and schemes. The activity of IL-2 in monotherapy or in association with immunotherapy is clinically relevant in hepatocarcinoma, mesothelioma and in malignant overflows as palliative treatment. Randomized trials would be required in order to be able to draw conclusions about its indication in other tumors.

Phase II study of belagenpumatucel-L, a transforming growth factor beta-2 antisense gene-modified allogeneic tumor cell vaccine in non-small-cell lung cancer

PURPOSE

Belagenpumatucel-L is a nonviral gene-based allogeneic tumor cell vaccine that demonstrates enhancement of tumor antigen recognition as a result of transforming growth factor beta-2 inhibition.

PATIENTS AND METHODS

We performed a randomized, dose-variable, phase II trial involving stages II, IIIA, IIIB, and IV non-small-cell lung cancer patients. Each patient received one of three doses (1.25, 2.5, or 5.0 x 10(7) cells/injection) of belagenpumatucel-L on a monthly or every other month schedule to a maximum of 16 injections. Immune function, safety, and anticancer activity were monitored.

RESULTS

Seventy-five patients (two stage II, 12 stage IIIA, 15 stage IIIB, and 46 stage IV patients) received a total of 550 vaccinations. No significant adverse events were observed. A dose-related survival difference was demonstrated in patients who received > or = 2.5 x 10(7) cells/injection (P = .0069). Focusing on the 61 late-stage (IIIB and IV) assessable patients, a 15% partial response rate was achieved. The estimated probabilities of surviving 1 and 2 years were 68% and 52%, respectively for the higher dose groups combined and 39% and 20%, respectively, for the low-dose group. Immune function was explored in the 61 advanced-stage (IIIB and IV) patients. Increased cytokine production (at week 12 compared with patients with progressive disease) was observed among clinical responders (interferon gamma, P = .006; interleukin [IL] -6, P = .004; IL-4, P = .007), who also displayed an elevated antibody-mediated response to vaccine HLAs (P = .014). Furthermore, positive enzyme-linked immunospot reactions to belagenpumatucel-L showed a correlation trend (P = .086) with clinical responsiveness in patients achieving stable disease or better.

CONCLUSION

Belagenpumatucel-L is well tolerated, and the survival advantage justifies further phase III evaluation.

Early variations of circulating interleukin-6 and interleukin-10 levels during thoracic radiotherapy are predictive for radiation pneumonitis

PURPOSE

To investigate variations of circulating serum levels of interleukin-6 (IL-6), tumor necrosis factor alpha (TNFalpha), and interleukin-10 (IL-10) during three-dimensional conformal radiation therapy (3D-CRT) in patients with non-small-cell lung cancer and correlate these variations with the occurrence of radiation pneumonitis.

PATIENTS AND METHODS

Ninety-six patients receiving 3D-CRT for stage I to III disease were evaluated prospectively. Circulating cytokine levels were determined before, every 2 weeks during, and at the end of treatment. Radiation pneumonitis was evaluated prospectively between 6 and 8 weeks after 3D-CRT. The predictive value of clinical, dosimetric, and biologic (cytokine levels) factors was evaluated both in univariate and multivariate analyses.

RESULTS

Forty patients (44%) experienced score 1 or more radiation pneumonitis. No association was found between baseline cytokine levels and the risk of radiation pneumonitis. In the whole population, mean levels of TNFalpha, IL-6, and IL-10 remained stable during radiotherapy. IL-6 levels were significantly higher (P = .047) during 3D-CRT in patients with radiation pneumonitis. In the multivariate analysis, covariations of IL-6 and IL-10 levels during the first 2 weeks of 3D-CRT were evidenced as independently predictive of radiation pneumonitis in this series (P = .011).

CONCLUSION

Early variations of circulating IL-6 and IL-10 levels during 3D-CRT are significantly associated with the risk of radiation pneumonitis. Variations of circulating IL-6 and IL-10 levels during 3D-CRT may serve as independent predictive factors for this complication.

Alveolar macrophage function is altered in patients with lung cancer

The alveolar macrophage (AM) is believed to be of central importance in the immune response against infection and tumour. We examined patients with lung cancer in order to evaluate the immuno-stimulatory potential of AM in lung cancer. Bronchoalveolar lavage fluid samples were obtained from patients with adenocarcinoma, squamous cell carcinoma, large cell undifferentiated lung carcinoma, small cell carcinoma and control subjects. AM were isolated and phagocytic function, flow cytometry and cytokine analysis were assessed. AM from patients with small and squamous cell carcinoma had impaired uptake in vitro of 40 nm fluorescent polystyrene beads. AM from patients with small, squamous and large cell undifferentiated carcinoma showed impaired uptake of 1000 nm fluorescent polystyrene beads. Secreted levels of TNF-alpha and IL-1 from AM of patients with small, squamous, and large cell undifferentiated carcinoma were decreased compared to controls. Secreted AM IL-6 levels were decreased in small and large cell undifferentiated carcinoma. AM from adenocarcinoma patients showed similar levels of IL-10, IL-6, IL-1 and TNF-alpha compared to controls. Phenotypic analysis demonstrated that patients with small cell carcinoma were the only group that showed a decrease in MHC class II surface expression. Surface expression of ICAM-1 and CD83 was decreased on AM from patients with large, squamous and small cell carcinoma compared to controls but not adenocarcinoma. Mannose receptor levels were only decreased on AM from patients with squamous and small cell carcinoma but not adenocarcinoma and large cell undifferentiated carcinoma. We conclude that there are type-specific alterations in uptake ability, cytokine secretion and phenotype of AM from lung cancer patients, which may result in an inability to stimulate anti-tumour immunity. The observed differences between lung cancer subgroups may explain previously reported inconsistencies in descriptions of AM characteristics in lung cancer.

The changes of CD4+CD25+/CD4+ proportion in spleen of tumor-bearing BALB/c mice

CD4+CD25+ regulatory T lymphocytes (TR) constitute 5-10% of peripheral CD4+ T cells in naive mice and humans, and play an important role in controlling immune responses. Accumulating evidences show that TR cells are involved in some physiological processes and pathologic conditions such as autoimmune diseases, transplantation tolerance and cancer, and might be a promising therapeutic target for these diseases.To evaluate the change of CD4+CD25+ TR cells in mouse tumor models, CD4+CD25+ subset in peripheral blood and spleen lymphocytes from normal or C26 colon-carcinoma-bearing BABL/c mice were analyzed by flow cytometry using double staining with CD4 and CD25 antibodies.The proportion of CD4+CD25+/CD4+ in spleen lymphocytes was found to be higher than that in peripheral blood lymphocytes in normal mice. No difference was observed in the proportion in peripheral blood lymphocytes between tumor bearing mice and normal mice, while there was a significant increase in the proportion in spleen lymphocytes in tumor bearing mice as compared with normal mice. Moreover, the proportion increased in accordance with the increase in the tumor sizes. The increase in the proportion was due to the decrease in CD4+ in lymphocytes, which is resulted from decreased CD4+CD25- subset in lymphocytes. Our observation suggests the CD4+CD25+/CD4+ proportion in spleen lymphocytes might be a sensitive index to evaluate the TR in tumor mouse models, and our results provide some information on strategies of antitumor immunotherapy targeting CD4+CD25+ regulatory T lymphocytes.

Multifaceted roles of cyclooxygenase-2 in lung cancer

Lung cancer is the leading cause of cancer death in the United States. Although the low 5-year survival rate (under 15%) has changed minimally in the last 25 years, new agents and combinations of agents that target tumor proliferation, invasion, and survival may lead to improvement in patient outcomes. There is evidence that cyclooxygenase-2 (COX-2) is overexpressed in lung cancer and promotes tumor proliferation, invasion, angiogenesis, and resistance to apoptosis. COX-2 inhibitors have been found to inhibit tumor growth in animal models and have demonstrated responses when combined with conventional therapy in phase II clinical trials. Further understanding of the mechanisms involved in COX-2-mediated tumorigenesis and its interaction with other molecules in lung cancer may lead to improved therapeutic strategies for this disease. In addition, delineation of how COX-2-dependent genes modulate the malignant phenotype will provide novel insights in lung cancer pathogenesis.

Evaluation of the potential immunotoxicity of 3-monochloro-1,2-propanediol in Balb/c mice

3-Monochloro-1,2-propanediol (MCPD) is a well-known by-product of acid-hydrolyzed soy sauce during its manufacturing process. MCPD has been reported genotoxic in vitro, and reproductive toxicity and carcinogenicity in rats. However, no previous studies have investigated MCPD-induced alterations in the immune system. In the present study, MCPD was administered by gavage for 14 days at 0, 25, 50, and 100 mg/kg per day to female Balb/c mice. The antibody-mediated immune response to sheep red blood cells (SRBC) was assessed using the antibody-forming cell (AFC) assay, and splenic cell phenotypes were quantified by flow cytometry. Hematological and histopathological changes were assessed. Mitogen-stimulated spleen lymphocyte proliferation and natural killer (NK) cell activity were evaluated. The T-lymphocyte blastogenesis by concanavalin A (Con A) or anti-CD3 and B-lymphocyte blastogenesis by lipopolysaccharide (LPS) were not significantly changed. There were no significant changes in the hematological and histopathological findings of MCPD-treated mice. However, the significant decrease in thymus weight was observed in 100 mg dose group, even though that did not change body weight gain. The cellularities of spleen and thymus were significantly reduced in high-dose group. Exposure to high dose of MCPD decreased the AFC response to SRBC in mice. There was a significant decrease in NK cell activity of mice treated with high dose of MCPD. These results indicate that MCPD could modulate the immune function in Balb/c mice.

Allogeneic vaccination with a B7.1 HLA-A gene-modified adenocarcinoma cell line in patients with advanced non-small-cell lung cancer

PURPOSE

To determine the safety, immunogenicity, and clinical response to an allogeneic tumor vaccine for non-small-cell lung cancer, we conducted a phase I trial in patients with advanced metastatic disease.

PATIENTS AND METHODS

We treated 19 patients with a vaccine based on an adenocarcinoma line (AD100) transfected with B7.1 (CD80) and HLA A1 or A2. Patients were vaccinated intradermally with 5 x 10(7) cells once every 2 weeks. Three vaccinations represented one course of treatment. If patients had complete response, partial response, or stable disease, they continued with the vaccinations for up to three courses (nine vaccinations). Immune response was assessed by a change between pre-study and postvaccination enzyme-linked immunospot frequency of purified CD8 T-cells secreting interferon-gamma in response to in vitro challenge with AD100.

RESULTS

Four patients experienced serious adverse events that were unrelated to vaccine. Another four patients experienced only minimal skin erythema. All but one patient had a measurable CD8 response after three immunizations. The immune response of six surviving, clinically responding patients shows that CD8 titers continue to be elevated up to 150 weeks, even after cessation of vaccination. Overall, one patient had a partial response, and five had stable disease. Median survival for all patients is 18 months (90% CI, 7 to 23 months), with corresponding estimates of 1-year, 2-year, and 3-year survival of 52%, 30%, and 30%, respectively. HLA matching of vaccine, age, sex, race, and pathology did not bear a significant relation to response.

CONCLUSION

Minimal toxicity and good survival in this small population suggest clinical benefit from vaccination.

Skin reactivity to histamine and expression of histamine receptors mRNA in lymphocytes of healthy subjects and non-small-cell lung cancer patients before and after surgery

Histamine modulates an immunological response through stimulation of appropriate receptor--H1R proinflammatory or H2R suppressive. The participation of histamine in regulation of an immunological response in the course of neoplastic disease is determined by the expression of particular receptor. The aim of our work was the investigation of the expression of mRNA of two types of histamine receptors in peripheral blood lymphocytes and the evaluation of skin-prick test with histamine in lung cancer patients before and after surgery. The investigation was performed on 15 patients qualified to surgery before and 7-10 days after treatment and on 12 healthy subjects. Reverse transcriptase polymerase chain reaction (RT-PCR) with primers labeled with fluorescent dyes was performed. Intensity of fluorescence was expressed as relative fluorescence units (RFU). The data were analysed using ABI Prism 310 GeneScan collection software Version 3.1. Skin-prick test with histamine was evaluated after 10 min by measuring the diameter of the weal. The expression of H1R and H2R mRNA in healthy subjects was not significantly different in contrast to the lung cancer patients in which a significant prevalence of H2R mRNA expression was observed before surgery and only slightly decreased after (P < 0.001). Skin-prick test--negative in one patient before surgery, after treatment was positive in all patients and the diameter of histamine weal was significantly increased (P < 0.001). One may assume that the prevalence of the expression of H2R mRNA in patients reflects the status of immunosuppression caused by cancer. Since histamine exerts its suppressive activity trough H2R it seems reasonably to include the antagonists of this receptor to the cancer therapy which may restore a relative balance between accessibility of both types of histamine receptors.

Analysis of the immunological microenvironment at the tumor site in patients with non-small cell lung cancer

BACKGROUND AND AIMS

Inactivation of tumor-infiltrating lymphocytes by immunomodulating cytokines shed by tumor cells into the tumor local microenvironment might be a potential escape strategy of various tumors from immune-immediate killing. Here, we provide an analysis of the cytokine profile at the tumor site in patients with non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

Using in situ hybridization (ISH), we determined the mRNA expression in lymphocytes and tumor cells for IL-2, INF-gamma, IL-12 (p40), IL-18, IL-4, IL-10, TGF-beta1, IL-1, IL-3, IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF), TNF-alpha, and TGF-alpha in five fresh pleural effusion samples and 18 tumor tissue samples of patients with NSCLC.

RESULTS

In pleural effusion as well as in tumor tissue of NSCLC patients, the mRNA expression of IL-4, IL-10, TGF-alpha, and TGF-beta1 was significantly higher than that of IL-2, IL-12, IL-18 and INF-gamma. In contrast, the analysis of tuberculosis pleural effusion samples revealed lower mRNA levels for all cytokines and did not show any significant difference among them.

CONCLUSION

The predominant mRNA expression of type II and immunosuppressive cytokines in pleural effusion and tumor tissue of NSCLC patients mirrors an immunosuppressive state in the immunological microenvironment. The present study may, therefore, help to elucidate mechanisms of tumor escape and contribute to the development of an effective immunomodulatory treatment of NSCLC.

Epidermal growth factor receptors and cyclooxygenase-2 in the pathogenesis of non-small cell lung cancer: potential targets for chemoprevention and systemic therapy

The epidermal growth factor receptor (EGFR) is part of a family of plasma membrane receptor tyrosine kinases that control many important cellular functions, from growth and proliferation to cell death. Cyclooxygenase (COX)-2 is an enzyme which catalyses the conversion of arachidonic acid to prostagladins and thromboxane. It is induced by various inflammatory stimuli, including the pro-inflammatory cytokines, Interleukin (IL)-1beta, Tumour Necrosis Factor (TNF)-alpha and IL-2. Both EGFR and COX-2 are over-expressed in non-small cell lung cancer (NSCLC) and have been implicated in the early stages of tumourigenesis. This paper considers their roles in the development and progression of lung cancer, their potential interactions, and reviews the recent progress in cancer therapies that are directed toward these targets. An increasing body of evidence suggests that selective inhibitors of both EGFR and COX-2 are potential therapeutic agents for the treatment of NSCLC, in the adjuvant, metastatic and chemopreventative settings.