Expression of IL-17 mRNA in ovarian cancer

The expression levels of transcription factors T-bet, GATA-3, RORγt and FOXP3 in peripheral blood lymphocyte (PBL) of patients with liver cancer and their significance

OBJECTIVES

To investigate the expression of transcriptional factors (TFs) T-bet, GATA-3, RORγt and FOXP in peripheral blood mononuclear cells (PBMC) of patients with hepatocellular carcinoma (HCC) and to evaluate the correlation between the imbalances of Th1/Th2, Th17/Treg at the expression levels and liver cancer Methods: The peripheral venous blood was drawn from 20 HCC-patients (HCC-group) and 20 health participants (C-group). The expression levels of Th1, Th2 and Th17 and the major Treg-specific TFs T-bet, GATA-3, RORγt and FOXP3 in the PBMC were measured with quantitative real-time PCR(RT-qPCR).

RESULTS

The mRNA level of Th1-specific TF T-bet in HCC-group was significantly lower than that of C-group (52.34±34.07 VS 104.01±56.00, P<0.01); the mRNA level of Th2-specifc TF, GATA-3, in HCC group was significantly higher than that in C-group (1.38±1.15 VS 0.58±0.65, P<0.05) and T-bet mRNA/GATA-3 mRNA ratio was significantly lower in HCC-group than in C-group (86.01±116.71 VS 461.88±708.81, P<0.05). The mRNA level of Th17-specific TF RORγt in HCC-group was significantly higher than that of C-group (72.32±32.82 VS 33.07±22.86, P<0.01). Treg-specific TF FOXP3 mRNA level was significant higher in HCC-group than in C-group (3.17±1.59 VS 1.39±1.13, P<0.01) CONCLUSION: T-bet mRNA level was reduced whereas GATA-3 mRNA level was increased and T-bet/GATA-3 ratio was significantly reduced in PBMC, indicating that Th1/Th2 ratio was of imbalance at TF levels in PBMC of HCC, displaying Th2 thrift phenomena. The mRNA levels of RORγt and FOXP3 in PBMC of HCC were significantly increased, indicating the existence of a predominant phenomenon of Th17- and Treg-expressing PBMC in HCC.

The role of interleukin 17 in tumour proliferation, angiogenesis, and metastasis

With 7.6 million deaths globally, cancer according to the World Health Organisation is still one of the leading causes of death worldwide. Interleukin 17 (IL-17) is a cytokine produced by Th17 cells, a T helper cell subset developed from an activated CD4+ T-cell. Whilst the importance of IL-17 in human autoimmune disease, inflammation, and pathogen defence reactions has already been established, its potential role in cancer progression still needs to be updated. Interestingly studies have demonstrated that IL-17 plays an intricate role in the pathophysiology of cancer, from tumorigenesis, proliferation, angiogenesis, and metastasis, to adapting the tumour in its ability to confer upon itself both immune, and chemotherapy resistance. This review will look into IL-17 and summarise the current information and data on its role in the pathophysiology of cancer as well as its potential application in the overall management of the disease.

Interleukin 17A rs3819024 A>G polymorphism is associated with an increased risk of gastric cardia adenocarcinoma in a Chinese population

Gastric cardia adenocarcinoma (GCA) is one of the most common malignant tumors. In addition to environmental risk factors, genetic factors might play an important role in GCA carcinogenesis. To evaluate the association between polymorphisms in the interleukin 17A (IL17A) gene on the development of GCA, we conducted a hospital-based case-control study. A total of 243 GCA cases and 476 controls were recruited and their genotypes were determined using a custom-by-design 48-Plex SNPscan™ Kit. IL17A rs3819024 A > G polymorphism was found to be associated with the increased risk of GCA. When the IL17A rs3819024 AA homozygote genotype was used as the reference group, the AG genotype was associated with a significantly increased risk of GCA (AG versus AA: adjusted OR = 1.53, 95% CI = 1.05-2.23, p = 0.026). However, there was no significant association between five other SNPs and GCA. Stratified analyses indicated that a significantly increased risk of GCA associated with the IL17A rs3819024 A > G polymorphism was evident among male patients, patients who drank alcohol or those who never smoked. These findings indicated that functional polymorphism IL17A rs3819024 A > G might contribute to GCA susceptibility. Future larger studies with more rigorous study designs are required to confirm the current findings.

Reduced interleukin-17 and transforming growth factor Beta levels in peripheral blood as indicators for following the course of bladder cancer

Interleukin (IL) 17 is produced by T-helper (Th) 17 with a vigorous effect on cells of the immune system playing important roles in pathogenesis of immune-mediated diseases, including autoimmune disorders and cancers. Therefore, the aim of current study was to determine the serum levels of IL-6, IL-17, and transforming growth factor beta (TGF-β) in Iranian bladder cancer patients, and to correlate them with disease status. Blood samples were collected from 40 bladder cancer patients and 38 healthy individuals with no history of malignancies or autoimmune disorders. The serum levels of IL-6, IL-17, and TGF-β were measured by the enzyme-linked immunosorbent assay (ELISA). The results showed that the levels of IL-17 (p<0.0001) and TGF-β (p<0.0001) were significantly lower in the patients compared to the controls. No significant differences in the level of serum IL-6 (p=0.16) was observed between the patients and controls. In addition, demographic characteristics between control and patients groups were not significantly different. As most of the cases studied in this investigation were in stage I and II, it is concluded that reduced Th17-related cytokines can be used as indicators for following the course and clinical stages of bladder carcinoma progress and immune response to cancer.

Inflammatory cytokines and VEGF measured in exhaled breath condensate are correlated with tumor mass in non-small cell lung cancer

Inflammation mediated by the immune system is known to be important in carcinogenesis and, specifically, T helper 17 cells have been reported to play a role in tumor progression by promoting neo-angiogenesis. The aim of this study was to investigate whether inflammatory cytokines and vascular endothelial growth factor (VEGF) levels in exhaled breath condensate (EBC) and in serum were related to tumor size in patients with non-small cell lung cancer (NSCLC). Il-6, IL-17, TNF-α and VEGF levels were measured in EBC and serum of 15 patients with stage I-IIA NSCLC and in 30 healthy controls by immunoassay. The tumor size was measured by a CT scan. The concentrations of IL-6, IL-17 and VEGF were significantly higher in EBC of patients with lung cancer, compared with controls, while only serum IL-6 concentration was higher in patients compared to controls. A significant correlation (r = 0.78, p = 0.001) was observed between EBC levels of IL-6 and IL-17; IL-17 was also correlated to EBC levels of the VEGF (r = 0.83, p < 0.001) and TNF-α (r = 0.62, p = 0.014). The tumor diameter was significantly correlated with EBC concentrations of VEGF (r = 0.58, p = 0.039), IL-6 (r = 0.67, p = 0.013) and IL-17 (r = 0.66, p = 0.017). Our results show a significant relationship between inflammatory and angiogenic markers, measured in EBC by a non-invasive method, and tumor mass.

Interleukin-17 and type 17 helper T cells in cancer management and research

Since their recent discovery, T helper 17 (Th17) cells have been frequently detected in the tumor microenvironment of many malignancies, but their clinical implications remain largely unknown. Interleukin-17 (IL-17) detection is commonly related with poor outcomes in colorectal cancers, yet its presence is associated with antitumor responses in ovarian carcinomas. Numerous experimental models illustrate the divergent roles of Th17 cells in tumor immunity, which appears to be mainly dependent on the tumor context (type, location, and stage of cancer). It is recognized that IL-17 is produced by a variety of cell types and that Th17 cells are endowed with a unique functional plasticity. Therefore, when trying to elucidate potential immune biomarkers and immunotargets, it is extremely important to make a clear dissociation between strategies targeting Th17 versus its hallmark cytokine, IL-17. In this review, we will summarize the data regarding the detection of IL-17 and Th17 in human cancers, consider the experimental evidence on their respective roles in antitumor activity, and discuss the potential of IL-17 as an immune target for therapeutic interventions.

Increased expression of IL17A in human gastric cancer and its potential roles in gastric carcinogenesis

Inflammatory cytokines modulate immune responses in the tumor microenvironment during progression. The role of interleukin (IL) 17A in cancer is currently under debate. We aim to investigate the expression of IL17A in situ tumors as well as in nontumor gastric mucosa tissues and further explore the functional significance of IL17A on gastric cancer cells in vitro. We found that compared with nontumor regions, the expression of IL17A were increased significantly in tumors of gastric cancer patients (P=0.007). The immunoreactivity for IL17A was found only in cytoplasm of inflammatory cells as well as vascular endothelial cells but not in tumor cells. Consistently, IL17A transcription was silenced in a variety of gastric cancer cell lines. In vitro, recombinant human IL17A protein promotes cell proliferation and monolayer wound healing of both AGS and SGC7901cells, in a dose-dependent manner. Besides, IL17A inhibits H2O2-induced cell apoptosis. Expression of IL6 and MMP13 mRNA was increased significantly after IL17A stimulation. These data suggest that accumulation of intratumoral IL17A-producing cells may promote gastric cancer progression directly or by inducing key signal transduction pathways implicated in gastric carcinogenesis.

Epithelial gp130/Stat3 functions: an intestinal signaling node in health and disease

A contiguous intestinal epithelial barrier safeguards against aberrant activation of the immune system and therefore requires molecular mechanisms that ensure effective wound-healing responses. During this processes cytokine-producing myeloid cells serve as rheostats that link the degree of wounding and local inflammation to the epithelial repair response. Likewise, intestinal inflammation is an important factor by which the microenvironment promotes tumorigenesis and the progression of established cancers by facilitating neoplastic cell survival and proliferation. Among the cytokines and chemokines orchestrating this process, those comprising the interleukin (IL) IL6, IL10/IL22 and IL17/IL23 families play a prominent role by virtue of converging on the latent Signal Transducer and Activator of Transcription (Stat)-3. Accordingly, aberrant and persistent Stat3 activation is a frequent observation in cancers of the gastrointestinal tract where it promotes "cancer hallmark capabilities" in the malignant epithelium and suppresses the anti-tumor response of innate and adaptive immune cells. Here, we discuss recent insights arising from situations where persistent activation of the gp130/Stat3 signaling cascades result from excessive abundance of IL6 family cytokines. In particular, we highlight novel and unique roles for IL11 in promoting intestinal wound-healing and, in its corrupted form, enabling and facilitating growth of inflammation-associated and sporadic gastrointestinal tumors.

Role of the interleukin 6 receptor family in epithelial ovarian cancer and its clinical implications

Ovarian cancer is the most lethal gynecological malignancy, with few effective treatment options in most cases. Therefore, understanding the biology of ovarian cancer remains an important area of research in order to improve clinical outcomes. Cytokine receptor signaling through the Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway is an essential component of normal development and homeostasis. However, numerous studies have implicated perturbation of this pathway in a range of cancers. In particular, members of the IL-6R family acting via the downstream STAT3 transcription factor play an important role in a number of solid tumors - including ovarian cancer - by altering the expression of target genes that impact on key phenotypes. This has led to the development of specific inhibitors of this pathway which are being used in combination with standard chemotherapeutic agents. This review focuses on the role of IL-6R family members in the etiology of epithelial ovarian cancer, and the application of therapies specifically targeting IL-6R signaling in this disease setting.

Interleukin 17A rs4711998 A>G polymorphism was associated with a decreased risk of esophageal cancer in a Chinese population

Esophageal cancer is the eighth most common cancer and sixth leading cause of cancer-associated death worldwide. Besides environmental risk factors, genetic factors might play an important role in the esophageal cancer carcinogenesis. We conducted a hospital-based case-control study to evaluate the genetic effects of functional single nucleotide polymorphisms (SNPs) in the interleukin 17A (IL17A) gene on the development of esophageal cancer. A total of 380 esophageal squamous cell carcinoma (ESCC) cases and 380 controls were recruited for this study. The genotypes were determined using a custom-by-design 48-Plex SNPscan Kit. IL17A rs4711998 A>G polymorphism was associated with the decreased risk of ESCC. When the IL17A rs4711998 AA homozygote genotype was used as the reference group, the AG genotype was associated with a significantly decreased risk for ESCC (AG vs. AA: adjusted odds ratio 0.72, 95% confidential interval 0.53-0.98, P = 0.039). However, there was no significant association between the other five SNPs and ESCC risk. Stratified analyses indicated that a significantly decreased risk of ESCC associated with the IL17A rs4711998 A>G polymorphism was evident among younger patients and patients who never smoking or drinking. These findings indicated that functional polymorphism IL17A rs4711998 A>G might contribute to ESCC susceptibility. However, our results were obtained with a limited sample size; the power of our analysis was low. Future larger studies with more rigorous study designs of other ethnic populations are required to confirm current findings.

Prognostic significance of IL-17 mRNA expression in peritoneal lavage in gastric cancer patients who underwent curative resection

Peritoneal dissemination is frequently detected in patients with advanced gastric cancer. The peritoneal cavity is a compartment in which an immunologic host-tumor interaction can occur. There are no reports on the relationship between IL-17 expression in peritoneal lavage and prognosis in gastric cancer patients. Therefore, we investigated the expression of IL-17 mRNA in peritoneal lavage from gastric cancer patients and assessed the association of its expression with clinicopathological parameters and prognosis. Peritoneal lavage was obtained from 114 patients with gastric cancer at initial surgery. Seventy-nine patients underwent curative resection. Among these 79 patients, IL-17 mRNA expression was associated with the depth of tumor invasion (p<0.05). Twelve of the 79 patients who underwent curative resection died, and 9 of those 12 developed peritoneal metastasis. Notably, among the 79 patients who underwent curative resection, those with high expression of IL-17 mRNA in peritoneal lavage had significantly prolonged survival when compared to these patients with low expression of IL-17 mRNA in peritoneal lavage (p<0.05) as evidence by the survival curves. In a multivariate analysis, low expression of IL-17 mRNA in peritoneal lavage and tumor size were found to be independent significant predictive factors for prognosis (HR, 7.91; 95% CI, 1.65-38.03) in the patients who underwent curative resection. IL-17 mRNA expression in peritoneal lavage is a reliable prognostic factor for patients undergoing curative resection for gastric cancer. Low IL-17 expression in the peritoneal cavity may correlate with cancer development in the peritoneal cavity in patients with gastric cancer.

Significance of interleukin 17-A expression in colorectal cancer and adenoma

AIM: To investigate the expression and role of interleukin-17 (IL-17) in colorectal cancer and adenoma.

METHODS: Tissue samples taken from patients with colorectal cancer or adenoma who were treated in our gastrointestinal endoscopy unit between 2009 and 2011 were used in this retrospective study. The expression of IL-17A in the above tissue samples was detected by immunohistochemistry. The relationship between IL-17A expression and clinicopathological characteristics and β-catenin localization was analyzed.

RESULTS: The positive rate of IL-17A expression was significantly higher in colorectal cancer, colorectal adenoma and ulcerative colitis than in normal colorectal tissue (54.2%, 45.8%, 50.0% vs 0.0%, all P < 0.01). IL-17A expression was not associated with tumor location, degree of differentiation, Duke's stage, lymph node metastasis, MVD or Ki-67 expression in colorectal cancer (all P > 0.05). IL-17A expression was also not associated with histological type, MVD, concomitant colorectal cancer, location, size, color, number or shape of adenomas (all P > 0.05) in colorectal adenoma. The expression of IL-17A was higher in adenomas with high-grade dysplasia than in those with mild to moderate dysplasia, but the difference was not significant (29.62 ± 26.77 vs 16.98 ± 10.62, P > 0.05). The expression of IL-17A was significantly higher in adenomas with nuclear expression of β-catenin than in those with cytoplasmic or membrane expression of β-catenin (29.11 ± 6.16 vs 16.95 ± 7.99, 15.10 ± 11.46, P = 0.038, 0.021).

CONCLUSION: IL-17A expression is elevated in colorectal cancer and adenomas and may mediate nuclear translocation of β-catenin.

Interleukin-6: an angiogenic target in solid tumours

During the past decade, incorporating anti-angiogenic agents into the therapeutic management of a myriad of malignancies has in certain cases made a significant impact on survival. However, the development of resistance to these drugs is inevitable and swift disease progression on their cessation often ensues. Hence, there is a drive to devise strategies that aim to enhance response to anti-angiogenic therapies by combining them with other targeted agents that facilitate evasion from resistance. The pleiotropic cytokine, interleukin-6 (IL-6), exerts pro-angiogenic effects in the tumour microenvironment of several solid malignancies and there is emerging evidence that reveals significant relationships between IL-6 signalling and treatment failure with antibodies directed against vascular endothelial growth factor (VEGF). This review summarises the role of IL-6 in pivotal angiogenic processes and preclinical/clinical research to support the future introduction of anti-IL-6 therapies to be utilised either in combination with other anti-angiogenic drugs or as a salvage therapy for patients with diseases that become refractory to these approaches.

Enrichment of regulatory T cells in invasive breast tumor correlates with the upregulation of IL-17A expression and invasiveness of the tumor

Breast cancer is a leading cause of neoplasia-associated death in women worldwide. Regulatory T (Treg) and Th17 cells are enriched within some tumors, but the role these cells play in invasive ductal carcinoma (IDC) of the breast is unknown. We show that CD25(+) CD4(+) T cells from PBMCs and tumor express high levels of Foxp3, GITR, CTLA-4, and CD103, indicating that tumor-infiltrating Treg cells are functional and possibly recruited by CCL22. Additionally, we observed upregulation of Th17-related molecules (IL-17A, RORC, and CCR6) and IL-17A produced by tumor-infiltrating CD4(+) and CD8(+) T lymphocytes. The angiogenic factors CXCL8, MMP-2, MMP-9, and vascular endothelial growth factor detected within the tumor are possibly induced by IL-17 and indicative of poor disease prognosis. Treg and Th17 cells were synchronically increased in IDC patients, with positive correlation between Foxp3, IL-17A, and RORC expression, and associated with tumor aggressiveness. Therefore, Treg and Th17 cells can affect disease progression by Treg-cell-mediated suppression of the effector T-cell response, as indicated by a decrease in the proliferation of T cells isolated from PBMCs of IDC patients and induction of angiogenic factors by IL-17-producing Th17. The understanding of regulation of the Treg/Th17 axis may result in novel perspectives for the control of invasive tumors.

Elevated IL-17A levels in early stages of bladder cancer regardless of smoking status

Aim: The interrelation between nicotine and IL-17A in bladder cancer (BC) patients was investigated. Methods: IL-17A in the sera of 121 BC patients who smoked nicotine, 80 nonsmoker BC patients, 29 and 30 age- and sex-matched healthy smokers and nonsmokers were also measured. Results: IL-17A was elevated in smoker and nonsmoker BC patients compared with smoker and nonsmoker controls (p = 0.004 and p = 0.004, respectively). The level of IL-17A in BC patients who smoked both water pipes and cigarettes were the highest (4.35±8.57 pg/ml), followed by BC water pipe users only (1.33±3.122 pg/ml) and cigarette smokers only (0.79±2.26 pg/ml, p = 0.001). IL-17A was elevated in lower stages (I and II) compared with higher stages (III and IV) of the disease (p = 0.013). Conclusion: IL-17A levels are elevated in some BC patients. IL-17A is an important factor in the inflammatory process during tumor progression, either as a defense mechanism or as a tumor-promoting factor.

Interleukin-17 induces AP-1 activity and cellular transformation via upregulation of tumor progression locus 2 activity

Inflammatory conditions elicited by extrinsic environmental factors promote malignant transformation, tumor growth and metastasis. Although the role of T cells in cancer promotion has been examined, little is known about the underlying molecular mechanisms of interleukin-17 A (IL-17A), a proinflammatory cytokine produced by activated CD4(+) memory T cells, in carcinogenesis. Here, we report that IL-17A induces neoplastic transformation of JB6 Cl41 cells through activation of tumor progression locus 2 (TPL2). IL-17A dose- and time-dependently increases TPL2 phosphorylation in JB6 Cl41 cells through IL-17A receptor. IL-17A activates mitogen-activated protein kinase/extracellular signal-regulated kinase kinases, c-jun N-terminal kinases and STAT3 signaling pathways, which are inhibited by a TPL2 kinase inhibitor (TKI). Furthermore, IL-17A activates c-fos and c-jun promoter activity, resulting in increased activator protein-1 (AP-1) activity. When small interfering RNA of IL-17A receptor (IL-17R), IL-17A and TPL2 were introduced into JB6 Cl41 cells, respectively, IL-17A-induced AP-1 activity was significantly decreased compared with control cells. Similarly, TPL2 inhibition suppressed AP-1 activity induced by IL-17A. The knockdown of IL-17R and TKI treatment in JB6 Cl41 cells resulted in decreased IL-17A-induced cell transformation. The in vivo chorioallantoic membrane assay also showed that IL-17A increased tumor formation of JB6 Cl41 cells, whereas TKI inhibited the tumorigenesis promoted by IL-17A. Consistent with these observations, knockdown of IL-17A and/or inhibition of TPL2 attenuated tumorigenicity of human breast cancer MCF7 cells. Together, our findings point to a critical role for the IL-17A-induced TPL2 signaling pathway in supporting cancer-associated inflammation in the tumor microenvironment. Therapeutic approaches that target this pathway may, therefore, effectively inhibit carcinogenesis.

Clinical significance of number of Th17 and Foxp3+Treg cells in peripheral blood of patients with gastric cancer

AIM: To analyze the clinical significance of the number of Th17 and CD4⁺CD25⁺Foxp3⁺Treg cells in peripheral blood of patients with gastric carcinoma.

METHODS: Peripheral blood samples were collected from patients with gastric cancer (n = 77) and healthy volunteers (n = 20) and used to separate PBMCs. The number of CD4⁺CD25⁺Foxp3⁺Treg was determined by flow cytometry, and the number of CD4⁺IL-17⁺Th17 was determined after co-stimulation with PMA and ionomycin. The clinical significance of the number of Treg and Th17 cells in patients with gastric carcinoma was then analyzed.

RESULTS: The numbers of Th17 and Treg cells in peripheral blood of patients with gastric cancer were significantly higher than those in normal controls (both P < 0.05). The number of Treg cells, not Th17 cells, was closely related to degree of tumor infiltration, lymph node metastasis, and tumor clinical stage.

CONCLUSION: Although the numbers of both Th17 and Treg cells are significantly higher in patients with gastric cancer, only the latter is related to tumor infiltration.

Relationship between the inflammatory molecular profile of breast carcinomas and distant metastasis development

Inflammatory conditions may promote tumor progression and aggressiveness. In previous reports, we found a group of breast cancer tumors characterized by metalloprotease-11 (MMP-11) expression by intratumoral mononuclear inflammatory cells (MICs), which was associated with distant metastasis development. Thus, in the present study we evaluated the relationship between MMP-11 expression by MICs, distant metastasis development, and a wide panel of inflammatory factors in breast carcinoma. In an initial approach, we analyzed 65 factors associated with tumor progression and inflammation, in a tumor population classified in good or bad prognosis, based on MMP-11 expression by intratumoral MICs. The most differentially expressed factors were then analyzed in a wider tumor population classified according to MMP-11 expression by MICs and also according to metastasis development. These analyses were carried out by Real-time PCR. The results showed that of the 65 starting factors analyzed, those related with MMP-11 expression by MICs were: IL-1, −5, −6, −8, −17, −18, MMP-1, TIMP-1, ADAM-8, −10, −15, −23, ADAMTS-1, −2, −15, Annexin A2, IFNβ, Claudin-3, CCL-3, MyD88, IRAK-4 and NFκB. Of them, factors more differentially expressed between both groups of tumors were IL-1, IL-5, IL-6, IL-17, IFNβ and NFκB. Thereafter, we confirmed in the wider tumor population, that there is a higher expression of those factors in tumors infiltrated by MMP-11 positive MICs. Altogether these results indicate that tumors developing worse prognosis and identified by MMP-11 expression by intratumoral MICs, shows an up-regulation of inflammatory-related genes.

Association between IL17 polymorphisms and risk of cervical cancer in Chinese women

Interleukin-17 (IL-17) is a proinflammatory cytokine that is associated with inflammation, autoimmune disorders, and even tumors. Previous studies revealed that a large group of human malignant tumors have abnormally high IL-17 expression. In the present study, we analyzed two single-nucleotide polymorphisms (SNPs) in the IL17A (rs2275913) and IL17F (rs763780) in 311 cervical cancer patients and 463 controls using TaqMan assays. Our results indicated that the frequencies of AA genotype and A allele of rs2275913 were significantly different between the cervical cancer patients and controls (P = 0.008, OR = 1.32, 95% CI, 1.07-1.62). Stratified analyses revealed that the polymorphism of rs2275913 was also associated with positive peritumor intravascular cancer emboli and high clinical stage. The genotype and allele frequencies of rs763780 did not show any difference between patients and controls or relate to patient clinical characteristics. Collectively, these findings suggested that IL17 gene polymorphism rs2275913 was associated with the susceptibility as well as positive peritumor intravascular cancer emboli and high clinical stage of cervical cancer in Chinese women.

Association analysis of IL-17A and IL-17F polymorphisms in Chinese Han women with breast cancer

BACKGROUND

Research into the etiology of breast cancer has recently focused on the role of the immunity and inflammation. The proinflammatory cytokines IL-17A and IL-17F can mediate inflammation and cancer. To evaluate the influences of IL-17A and IL-17F gene polymorphisms on the risk of sporadic breast cancer, a case-control study was conducted in Chinese Han women.

METHODOLOGY AND PRINCIPAL FINDINGS

We genotyped three single-nucleotide polymorphisms (SNPs) in IL-17A (rs2275913, rs3819025 and rs3748067) and five SNPs in IL-17F (rs7771511, rs9382084, rs12203582, rs1266828 and rs763780) to determine the haplotypes in 491 women with breast cancer and 502 healthy individuals. The genotypes were determined using the SNaPshot technique. The differences in the genotypic distribution between breast cancer patients and healthy controls were analyzed with the Chi-square test for trends. For rs2275913 in IL-17A, the frequency of the AA genotype was higher in patients than controls (P = 0.0016). The clinical features analysis demonstrated significant associations between IL-17 SNPs and tumor protein 53 (P53), progesterone receptor (PR), human epidermal growth factor receptor 2 (Her-2) and triple-negative (ER-/PR-/Her-2-) status. In addition, the haplotype analysis indicated that the frequency of the haplotype A(rs2275913)G(rs3819025)G(rs3748067), located in the IL-17A linkage disequilibrium (LD) block, was higher in patients than in controls (P = 0.0471 after correction for multiple testing).

CONCLUSIONS AND SIGNIFICANCE

Our results suggested that SNPs in IL-17A but not IL-17F were associated with the risk of breast cancer. Both IL-17A and IL-17F gene polymorphisms may provide valuable information for predicting the prognosis of breast cancer in Chinese women.

A role for T-bet-mediated tumour immune surveillance in anti-IL-17A treatment of lung cancer

Lung cancer is the leading cause of cancer deaths worldwide. The cytokine interleukin-17A supports tumour vascularization and growth, however, its role in lung cancer is unknown. Here we show, in the lungs of patients with lung adenocarcinoma, an increase in interleukin-17A that is inversely correlated with the expression of T-bet and correlated with the T regulatory cell transcription factor Foxp3. Local targeting of interleukin-17A in experimental lung adenocarcinoma results in a reduction in tumour load, local expansion of interferon-γ-producing CD4(+) T cells and a reduction in lung CD4(+)CD25(+)Foxp3(+) regulatory T cells. T-bet((-/-)) mice have a significantly higher tumour load compared with wild-type mice. This is associated with the local upregulation of interleukin-23 and induction of interleukin-17A/interleukin-17R-expressing T cells infiltrating the tumour. Local anti-interleukin-17A antibody treatment partially improves the survival of T-bet((-/-)) mice. These results suggest that local anti-interleukin-17A antibody therapy could be considered for the treatment of lung tumours.

Interleukin 17 Induces Up-Regulation of Chemokine and Cytokine Expression Via Activation of the Nuclear Factor κB and Extracellular Signal–Regulated Kinase 1/2 Pathways in Gynecologic Cancer Cell Lines

Objectives

Previous studies have revealed that interleukin 17 (IL-17) contributes to pathological processes in many solid tumors. However, the roles of IL-17 in gynecologic cancer still remain elusive, hindering the deep understanding of gynecologic tumorigenesis.

Methods

In the present study, to delineate the functional roles of IL-17 in gynecologic cancer, IL-17 stimulation was introduced in cell lines of 3 gynecologic cancers, and IL-17–induced expression of chemokines and cytokines and possible signaling pathways were investigated.

Results

Our results showed that in HEC-1-B (human endometrial cancer) cells, IL-17 stimulation induced mRNA level increases of CCL2, CCL5, CCL20, CXCL2, and IL-8. Similar treatment in HeLa cells caused increases in the mRNA levels of CCL2, CXCL2, IL-6, and IL-8, and in SKOV3 cells, mRNA levels of CCL2, CCL20, CXCL1, CXCL2, IL-6, and IL-8 increased. The increases in mRNA levels induced by IL-17 were dose- and time-dependent. Furthermore, with the addition of the NF-κB (nuclear factor κ–light-chain–enhancer of activated B) and extracellular signal–regulated kinase inhibitors pyrrolidine dithiocarbamate and PD98059, the IL-17–induced CCL2 mRNA level was significantly compromised. IL-17 stimulation also activated phosphorylation of IκBα and extracellular signal–regulated kinase 1/2 in a time-dependent manner.

Conclusion

These results demonstrated that IL-17 may regulate chemokines and cytokines in gynecologic cancers.

Increased IL-17-producing CD4(+) T cells in patients with esophageal cancer

Increased interleukin-17 (IL-17)-producing Th (Th17) cells have been described in a variety of human carcinoma cases, however, the mechanism of Th17 cells' accumulation in a tumor microenvironment remains elusive. This study was designed to investigate whether Th17 cells were involved in the development of esophageal cancer. We found that the proportion of Th17 cells increased within the peripheral blood and tumor tissues of esophageal cancer patients. Furthermore, the proportion of circulating Th17 cells was higher in advanced esophageal cancer patients than that in early esophageal cancer patients. In addition, the Th17 cells differentiation-related cytokines (IL-23, IL-1β, and IL-6) and accumulation-related chemokines (CCL22 and CCL20) were present in a tumor microenvironment. Therefore, the findings may partly explain the cause for the increased proportion of Th17 cells and indicate a potential prognostic marker of Th17 cells in esophageal cancer.

The accumulation and prognosis value of tumor infiltrating IL-17 producing cells in esophageal squamous cell carcinoma

BACKGROUND

The role of IL-17 producing cells in tumors is controversial. In the present study, we investigated the prognostic value of measuring tumor-infiltrating IL-17 producing cell levels in human esophageal squamous cell carcinoma (ESCC).

METHODOLOGY/PRINCIPAL FINDINGS

Immunohistochemical staining was performed to investigate the levels of IL-17+ tumor infiltrating lymphocytes (TILs), as well as CD8+ cytotoxic T lymphocytes (CTLs) and CD57+ natural killer (NK) cells from 181 ESCC patients. The prognostic value of measuring the densities of IL-17+TILs and the correlation with CTLs and NK was evaluated. IL-17 producing cells were detected in esophageal squamous cell carcinoma tissues. The IL-17 producing cells were major CD4 positive, but Foxp3 negative. The median level of IL-17+TILs was 3.90 cells/high power microscopic field (HPF). The density of IL-17 producing cells correlated negatively with T stage (P=0.042). The higher densities of tumor infiltrating IL-17+ lymphocytes were associated with better overall survival (P=0.031). Furthermore, we found that there were positive correlations between levels of IL-17 producing cells and the densities of CD8+cells, as well as CD57+cells (r=0.198, P=0.008 for CD8+ cells and r=0.261, P<0.001 for CD57+ cells, respectively). The prognosis analysis also showed that the higher levels of CD8+ CTLs and CD57+ NK cells correlated with better overall survival of ESCC patients.

CONCLUSIONS

Our study suggests that tumor infiltrating IL-17 producing cells in ESCC patients may have protective roles in the tumor microenvironment and may be treated as a prognostic marker for ESCC patients.

IL-17 is associated with poor prognosis and promotes angiogenesis via stimulating VEGF production of cancer cells in colorectal carcinoma

IL-17, which exerts strong pro-inflammatory effects, has emerged as an important mediator in inflammation-associated cancer. However, the characteristics of IL-17-producing cells, the relevance of IL-17 to clinical parameters and its function in the development and progression of colorectal carcinoma still remain to be explored. In the present study, we first found the levels of IL-17 producing cells were significantly increased in the tumor regions of samples from colorectal carcinoma patients compared with non-tumor regions. Confocal microscopic analysis showed co-staining of IL-17 with CD4 and CD68, indicating IL-17 in colorectal carcinoma was expressed by macrophage and Th17. High expression of IL-17 was associated with high microvessel density. Univariate and multivariate analysis revealed that IL-17 was an independent prognostic factor for overall survival. To explore the underlying mechanisms of IL-17 in angiogenesis, we used PCR-array to find pro-angiogenic factor in cancer cells specifically induced by IL-17, then validated VEGF as one of factors in IL-17-mediated angiogenesis with the use of quantitative RT-PCR, ELISA and VEGF immunohistochemistry. Our results propose IL-17 as a novel indicator of prognosis in the patients with colorectal carcinoma and could serve as a novel therapeutic target for colorectal carcinoma, furthermore our results indicate that IL-17 producing cells may facilitate development of colorectal carcinoma by fostering angiogenesis via promote VEGF production from cancer cells.

Interleukin-17 synergizes with IFNγ or TNFα to promote inflammatory mediator release and intercellular adhesion molecule-1 (ICAM-1) expression in human intervertebral disc cells

Interleukin-17 (IL-17) is a cytokine recently shown to be elevated, along with interferon-γ (IFNγ) and tumor necrosis factor (TNFα), in degenerated and herniated intervertebral disc (IVD) tissues, suggesting a role for these cytokines in intervertebral disc disease. The objective of our study was to investigate the involvement of IL-17 and costimulants IFNγ and TNFα in intervertebral disc pathology. Cells were isolated from anulus fibrosus and nucleus pulposus tissues of patients undergoing surgery for intervertebral disc degeneration or scoliosis. The production of inflammatory mediators, nitric oxide (NOx), prostaglandin E2 (PGE2) and interleukin-6 (IL-6), as well as intercellular adhesion molecule (ICAM-1) expression, were quantified for cultured cells following exposure to IL-17, IFNγ, and TNFα. Intervertebral disc cells exposed to IL-17, IFNγ, or TNFα showed a remarkable increase in inflammatory mediator release and ICAM-1 expression (GLM and ANOVA, p < 0.05). Addition of IFNγ or TNFα to IL-17 demonstrated a synergistic increase in inflammatory mediator release, and a marked increase in ICAM-1 expression. These findings suggest that IVD cells not only respond with a catabolic phenotype to IL-17 and costimulants IFNγ and TNFα, but also express surface ligands with consequent potential to recruit additional lymphocytes and immune cells to the IVD microenvironment. IL-17 may be an important regulator of inflammation in the IVD pathologies.

Tumor-infiltrating IL-17-producing gammadelta T cells support the progression of tumor by promoting angiogenesis

Based on the evidence that IL-17 is a key cytokine involved in various inflammatory diseases, we explored the critical role of IL-17-producing gammadelta T cells for tumor development in tumor-bearing mouse model. IL-17(-/-) mice exhibited a significant reduction of tumor growth, concomitantly with the decrease of vascular density at lesion area, indicating a pro-tumor property of IL-17. Among tumor-infiltrating lymphocytes (TIL), gammadelta T cells were the major cellular source of IL-17. Analysis of TCR repertoires in TIL-gammadelta T cells showed that circulating gammadelta T cells, but not skin resident Vgamma5(+)gammadelta T cells, produced IL-17. Neutralizing antibodies against IL-23, IL-6, and TGF-beta, which were produced within the tumor microenvironment, inhibited the induction of IL-17-producing gammadelta T cells. IL-17 production by tumor-infiltrating gammadelta T cells was blocked by anti-gammadeltaTCR or anti-NKG2D antibodies, indicating that these ligands, expressed within the tumor microenvironment, are involved in gammadelta T-cell activation. The IL-17-producing TIL-gammadelta T cells exhibited reduced levels of perforin mRNA expression, but increased levels of COX-2 mRNA expression. Together, our findings support the novel concept that IL-17-producing gammadelta T cells, generated in response to tumor microenvironment, act as tumor-promoting cells by inducing angiogenesis.

Role of interleukin-17 in lymphangiogenesis in non-small-cell lung cancer: Enhanced production of vascular endothelial growth factor C in non-small-cell lung carcinoma cells

Interleukin-17 (IL-17), a potent pro-inflammatory cytokine, plays an active role in inflammation and cancer. Recently, we found that increased IL-17-producing cells correlate with poor survival and increased lymphangiogenesis in non-small-cell lung cancer (NSCLC), but the mechanism is unknown. Here, we show that IL-17 promotes lymphangiogenesis via inducing vascular endothelial growth factor-C (VEGF-C) production by lung cancer cells. We found that IL-17 receptor (IL-17R) is expressed on the surface of Lewis lung carcinoma (LLC) cells but not on lymphatic endothelial cells (LEC). Moreover, LEC chemotaxis and tube formation (measures of net lymphangiogenic potential) were increased by conditioned medium from recombinant mouse IL-17 (rmIL-17)-stimulated LLC but not by rmIL-17. Interleukin-17 increased production of VEGF-C in lung cancer cell lines. The enhanced chemotaxis and endothelial cord formation in the presence of LLC/rmIL-17 was inhibited by addition of recombinant mouse VEGF R3/Fc chimera. Treatment of the A549 cells with rIL-17 significantly increased VEGF-C expression, which was extracellular signal-regulated protein kinase 1/2 (ERK 1/2) dependent. Importantly, we found significant correlations between IL-17 expression, VEGF-C expression and lymphatic vascular density (LVD) in NSCLC. We conclude that IL-17 is involved in lymphangiogenesis in NSCLC by enhancing production of VEGF-C, and IL-17 may be an important target for the treatment of NSCLC.

Does IL-17 play a role in hepatic dysfunction of scrub typhus patients?

Scrub typhus is a zoonotic disease that is caused by Orientia tsutsugamushi. Although hepatic dysfunction occurred in 77-96.7% of the scrub typhus patients, its mechanism is unknown. IL-17 is a potent proinflammatory cytokine known for its role in several chronic disease conditions. Abundant IL-17 was found in conditions affected by microbial pathogens, including the synovial fluid of patients with Lyme arthritis or Chlamydia-induced reactive arthritis, Helicobacter pylori-infected gastric mucosa, and listeria infection. It is also suggested as a marker of acute hepatic injury. In our study, we postulated that IL-17 might be a cytokine with a role in hepatic dysfunction in scrub typhus. In September-November 2006, our study involved 43 patients with Boryong-type scrub typhus patients and 40 age- and sex-matched control healthy people. Scrub typhus was confirmed on the basis of immunofluorescence and a nested polymerase chain reaction assay. IL-17 was measured using human IL-17 immunoassay. We gathered the clinical and laboratory data by chart reviews. We used an independent t-test, Kolmogorov-Smirnov test, and correlation analysis. The IL-17 levels were significantly higher in scrub typhus patients than in the healthy group. Also, the patients with scrub typhus showed significantly higher aspartate aminotransferase and alanine aminotransferase levels, and lower hemoglobin levels than the healthy group. However, in our correlation analysis, we did not find any correlation between IL-17 and hepatic, kidney, and hemogram panels. The IL-17 level in patients with headaches was higher than in patients without headaches, showing a borderline significance. This suggests that IL-17 level might be a cause of a vasculitis-associated headache. More prospective, large-scale studies are needed about the mechanism of hepatic dysfunction and headaches in scrub typhus patients.

Th17 cells: positive or negative role in tumor?

Th17 cells have been recently identified as a distinct Th cell lineage and found in an experimental animal model of cancer and in human cancers, but whether these cells promote tumor growth or regulate antitumor responses remains controversial. This review provides a summary of the current literature regarding interleukin (IL)-17/IL-23 and Th17 cells in cancer and discusses their potential roles in cancer development. Finally, we note several issues in this research area that must be resolved before the design of novel therapeutic approaches specifically targeting Th17 cells in cancer become feasible.

Th17 cells: the emerging reciprocal partner of regulatory T cells in the liver

T helper cells that produce interleukin-17 (IL-17) (Th17 cells) have recently been identified as the third distinct subset of effector T cells, the differentiation of which depends on specific transcription nuclear factor retinoic acid-related orphan nuclear receptor-gammat. Emerging data have suggested that Th17 cells play an important role in innate immunity, adaptive immunity and autoimmunity. Interestingly, there is a reciprocal relationship between Th17 cells and regulatory T cells (Treg), not only in development, but also in their effector function. Transforming growth factor (TGF)-beta induces Treg-specific transcription factor Forkhead box P3(FOXP3), while the addition of IL-6 to TGF-beta inhibits the generation of Treg cells and induces Th17 cells. It is proposed that the fine balance between Th17 and Treg cells is crucial for maintenance of immune homeostasis. In addition to IL-6, other factors such as retinoic acid, rapamycin, or cytokines (e.g., IL-2 and IL-27) could dictate the balance between Th17 and Treg cells. Since Treg cells play an important role in hepatic immunity with overregulation in chronic viral hepatitis and hepatic carcinoma, and inadequate inhibition in autoimmune liver diseases, graft rejection and acute liver failure, it is reasonable to assume that Th17 cells may play a reciprocal role in these diseases. Thus, future research on the Treg/Th17 balance may provide an opportunity to illustrate the pathogenesis of hepatic inflammation and to explore new therapeutic targets for immune-related liver diseases.

The Role of T-Helper 17 (Th17) Cells in Patients with Medulloblastoma

As a new member of the CD4+ effector T-cell family, T-helper 17 (Th17) cells, have emerged as an important mediator in inflammatory and autoimmune diseases. Th17 cells preferentially produce interleukin (IL)-17A, IL-17F, IL-21, IL-22, and IL-26 in humans. Recent studies suggest a potential role for Th17 cells in tumour development. The current study was designed to investigate the possible involvement of Th17 cells in the brain tumour medulloblastoma. Compared with 17 healthy volunteers, 23 patients with medulloblastoma had a higher proportion of Th17 cells in their peripheral blood. Increased populations of Th17 cells were also present in medulloblastoma-infiltrating T-cells. Furthermore, the mRNA levels for Th17-related factors (IL-17, IL-23 and retinoid orphan nuclear receptor) in tumour tissues and the serum concentrations of IL-17 and IL-23 protein were significantly increased in patients with medulloblastoma. The results indicate that Th17 cells may contribute to medulloblastoma pathogenesis.

MAP17 is associated with the T-helper cell cytokine-induced down-regulation of filaggrin transcription in human keratinocytes

In the meta-analysis of public microarray databases for different skin diseases, we revealed seven commonly up-regulated genes, DSG3, KRT6, MAP17, PLSCR1, RPM2, SOD2 and SPRR2B. We postulated that the genes selected from the meta-analysis may be potentially associated with the abnormal keratinocyte differentiation. To demonstrate this postulation, we alternatively evaluated whether the genes of interest in the meta-analysis can be regulated by T-helper (Th) cell cytokines in normal human epidermal keratinocytes (NHEK). We found that MAP17 was significantly up-regulated in response to interferon-gamma, interleukin 4 (IL-4), IL-6, IL-17A or IL-22 in NHEK. Interestingly, MAP17 was originally reported to interact with PDZK1; in turn, the PDZK1 gene is localized within the atopic dermatitis-linked region on human chromosome 1q21. In an attempt to evaluate whether MAP17 regulates the expression of cornified envelope-associated genes at the 1q21 locus, such as filaggrin, loricrin and involucrin, we found that the over-expression of MAP17 in HaCaT keratinocytes significantly decreased the expression of filaggrin. Taken together, the Th cell cytokine-induced up-regulation of MAP17 expression may be linked to the down-regulation of filaggrin in NHEK, which may be associated with the abnormal epidermal differentiation observed in the dermatological diseases.

Association of interleukin-23 receptor gene polymorphisms with risk of ovarian cancer

Among gynecological malignancies, ovarian cancer is the leading cause of death. The overall 5-year survival rate remains poor, and the pathogenesis is unknown. The interleukin-23 receptor (IL23R) is known to be critically involved in the carcinogenesis of different malignant tumors. To assess the role of IL23R in ovarian cancer, we conducted a study to investigate the polymorphisms of the IL23R gene in 96 Han Chinese women with histologically proven ovarian cancer. Polymerase chain reaction-restriction fragment length polymorphism was used for genotyping. In all three single nucleotide polymorphisms of IL23R studied, the distribution of genotype and allele frequencies of rs10889677 differed significantly between patients and controls. The frequency of allele C of rs10889677 was significantly increased in cases compared with controls (0.281 vs. 0.183, odds ratio OR=1.752, 95% confidence interval CI=1.107-2.772). Furthermore, when stratified by tumor stage, we found that the allele frequencies of rs11465817 differed significantly between FIGO stage I+II and III+IV. The higher frequency of allele A was significantly associated with advanced ovarian cancer (P=0.027, OR=2.087, 95% CI=1.083-4.023). These findings indicate that IL23R polymorphisms may play an important role in the susceptibility and prognosis of ovarian cancer in the Chinese population.

Translational mini-review series on Th17 cells: development of mouse and human T helper 17 cells

There has been a considerable amount of interest in the immunological community about new phenotypic subsets of CD4(+) T cells, particularly cells that produce the cytokine interleukin (IL)-17 [named T helper type 17 (Th17) cells]. While the initial discovery of Th17 cells and the pathways that controlled their development was in the mouse, recent attention has shifted to the existence of these cells and the relevant upstream cytokine signals in humans. While it is clear that CD4(+) T cells producing IL-17 exist in vivo, their relevance to disease pathogenesis is only just being understood. In this paper, we review the data regarding the generation of human Th17 cells in vitro and the evidence that this effector population is important in human disease states.

Tumor microenvironments direct the recruitment and expansion of human Th17 cells

Although Th17 cells play critical roles in the pathogenesis of many inflammatory and autoimmune diseases, their prevalence among tumor-infiltrating lymphocytes (TILs) and function in human tumor immunity remains largely unknown. We have recently demonstrated high percentages of Th17 cells in TILs from ovarian cancer patients, but the mechanisms of accumulation of these Th17 cells in the tumor microenvironment are still unclear. In this study, we further showed elevated Th17 cell populations in the TILs obtained from melanoma and breast and colon cancers, suggesting that development of tumor-infiltrating CD4(+) Th17 cells may be a general feature in cancer patients. We then demonstrated that tumor microenvironmental RANTES and MCP-1 secreted by tumor cells and tumor-derived fibroblasts mediate the recruitment of Th17 cells. In addition to their recruitment, we found that tumor cells and tumor-derived fibroblasts produce a proinflammatory cytokine milieu as well as provide cell-cell contact engagement that facilitates the generation and expansion of Th17 cells. We also showed that inflammatory TLR and nucleotide oligomerization binding domain 2 signaling promote the attraction and generation of Th17 cells induced by tumor cells and tumor-derived fibroblasts. These results identify Th17 cells as an important component of human TILs, demonstrate mechanisms involved in the recruitment and regulation of Th17 cells in tumor microenvironments, and provide new insights relevant for the development of novel cancer immunotherapeutic approaches.

IL-17RC: a partner in IL-17 signaling and beyond

The interleukin (IL)-17 cytokine family members IL-17A and IL-17F mediate inflammatory activities via the IL-17 receptor (IL-17R) complex, comprised of the IL-17RA and IL-17RC subunits. Proper regulation of the IL-17 signaling axis results in effective host defense against extracellular pathogens, while aberrant signaling can drive autoimmune pathology. Elucidating the molecular mechanisms underlying IL-17 signal transduction can yield an enhanced understanding of inflammatory immune processes and also create an avenue for therapeutic intervention in the treatment of IL-17-dependent diseases. To date, the fundamental signaling mechanisms used by the IL-17R complex are still incompletely defined. While current structure-function studies have primarily focused on the IL-17RA subunit, recent research indicates that the IL-17RC subunit plays a key role in modulating IL-17 responses. This review will examine what is known regarding IL-17RC function and provide a framework for future work on this subunit and its impact on human health.

Systematic analysis of immune infiltrates in high-grade serous ovarian cancer reveals CD20, FoxP3 and TIA-1 as positive prognostic factors

Background

Tumor-infiltrating T cells are associated with survival in epithelial ovarian cancer (EOC), but their functional status is poorly understood, especially relative to the different risk categories and histological subtypes of EOC.

Methodology/Principal Findings

Tissue microarrays containing high-grade serous, endometrioid, mucinous and clear cell tumors were analyzed immunohistochemically for the presence of lymphocytes, dendritic cells, neutrophils, macrophages, MHC class I and II, and various markers of activation and inflammation. In high-grade serous tumors from optimally debulked patients, positive associations were seen between intraepithelial cells expressing CD3, CD4, CD8, CD45RO, CD25, TIA-1, Granzyme B, FoxP3, CD20, and CD68, as well as expression of MHC class I and II by tumor cells. Disease-specific survival was positively associated with the markers CD8, CD3, FoxP3, TIA-1, CD20, MHC class I and class II. In other histological subtypes, immune infiltrates were less prevalent, and the only markers associated with survival were MHC class II (positive association in endometrioid cases) and myeloperoxidase (negative association in clear cell cases).

Conclusions/Significance

Host immune responses to EOC vary widely according to histological subtype and the extent of residual disease. TIA-1, FoxP3 and CD20 emerge as new positive prognostic factors in high-grade serous EOC from optimally debulked patients.

Malignant B cells skew the balance of regulatory T cells and TH17 cells in B-cell non-Hodgkin's lymphoma

Using biopsy specimens from patients with B-cell non-Hodgkin's lymphoma, we observed a significantly low frequency of T(H)17 cells, including several samples with no detectable amount of interleukin (IL)-17-producing cells present in the tumor microenvironment. We found that, in the absence of lymphoma B cells, treatment with IL-1beta/IL-6 or lipopolysaccharide (LPS) enhanced IL-17 expression in CD4(+) T cells and this enhancement was attenuated when CD4(+) T cells were cocultured with lymphoma B cells. Blockade of CD27-CD70 or CD28-CD80/86 interactions by anti-CD70 or anti-CD80/86 antibodies restored LPS-mediated induction of IL-17 expression in CD4(+) T cells cocultured with lymphoma B cells. Because a subset of lymphoma B cells express IL-2 and given that IL-2 signaling is critically important in the development of regulatory T (T(reg)) cells, we tested the role of IL-2 signaling in T(H)17 cell development. We found that treatment with anti-IL-2 antibody to interrupt IL-2 signaling significantly inhibited Foxp3 expression in CD4(+) T cells. In contrast, interruption of IL-2 signaling up-regulated IL-17 expression in CD4(+) T cells and restored lymphoma-mediated down-regulation of IL-17-producing cells. Furthermore, the reversal of T(reg) cell activity by LPS or CpG-A resulted in an enhancement of IL-17-producing cells. Taken together, our study indicated that lymphoma B cells play an important role in skewing the balance between T(reg) and T(H)17 cells resulting in the establishment of a profoundly inhibitory tumor microenvironment.

Th17 cells in human disease

SUMMARY

Our understanding of the role of T cells in human disease is undergoing revision as a result of the discovery of T-helper 17 (Th17) cells, a unique CD4(+) T-cell subset characterized by production of interleukin-17 (IL-17). IL-17 is a highly inflammatory cytokine with robust effects on stromal cells in many tissues. Recent data in humans and mice suggest that Th17 cells play an important role in the pathogenesis of a diverse group of immune-mediated diseases, including psoriasis, rheumatoid arthritis, multiple sclerosis, inflammatory bowel disease, and asthma. Initial reports also propose a role for Th17 cells in tumorigenesis and transplant rejection. Important differences, as well as many similarities, are emerging when the biology of Th17 cells in the mouse is compared with corresponding phenomena in humans. As our understanding of human Th17 biology grows, the mechanisms underlying many diseases are becoming more apparent, resulting in a new appreciation for both previously known and more recently discovered cytokines, chemokines, and feedback mechanisms. Given the strong association between excessive Th17 activity and human disease, new therapeutic approaches targeting Th17 cells are highly promising, but the potential safety of such treatments may be limited by the role of these cells in normal host defenses against infection.

Th17 cells in human disease

SUMMARY

Our understanding of the role of T cells in human disease is undergoing revision as a result of the discovery of T-helper 17 (Th17) cells, a unique CD4(+) T-cell subset characterized by production of interleukin-17 (IL-17). IL-17 is a highly inflammatory cytokine with robust effects on stromal cells in many tissues. Recent data in humans and mice suggest that Th17 cells play an important role in the pathogenesis of a diverse group of immune-mediated diseases, including psoriasis, rheumatoid arthritis, multiple sclerosis, inflammatory bowel disease, and asthma. Initial reports also propose a role for Th17 cells in tumorigenesis and transplant rejection. Important differences, as well as many similarities, are emerging when the biology of Th17 cells in the mouse is compared with corresponding phenomena in humans. As our understanding of human Th17 biology grows, the mechanisms underlying many diseases are becoming more apparent, resulting in a new appreciation for both previously known and more recently discovered cytokines, chemokines, and feedback mechanisms. Given the strong association between excessive Th17 activity and human disease, new therapeutic approaches targeting Th17 cells are highly promising, but the potential safety of such treatments may be limited by the role of these cells in normal host defenses against infection.