Increased prevalence of interleukin-17-producing CD4(+) tumor infiltrating lymphocytes in human oral squamous cell carcinoma

Poor Dental Health as a Risk Factor for Alveolar Ridge Malignancies

OBJECTIVE

To determine the association between poor dental health and risk of oral cavity squamous cell cancer (OCSCC) at individual tumor subsites.

STUDY DESIGN

Case-control and cross-sectional METHODS: A case-control study was performed using a population-based cohort in North Carolina (Carolina Head and Neck Cancer Epidemiology Study [CHANCE]). A secondary cross-sectional analysis was performed with an institutional cohort (WashU/Siteman). Cases were adults with primary OCSCC and an identifiable tumor subsite. In the CHANCE cohort, controls were adults without head and neck cancer. In the Washington University/Siteman cohort, patients with tongue cancer served as the comparator group. We used number of missing teeth (categorized 0-6, 7-24, 25-28) as a surrogate for poor dental health, which was self-reported in CHANCE and measured on a pretreatment computed tomography scan in the WashU/Siteman study. Adjusted odds ratios (aORs) for missing teeth were estimated for each tumor subsite using binomial logistic regression models.

RESULTS

Near complete tooth loss (25-28 teeth) was associated with a 3.5-fold increased risk of alveolar ridge malignancy (aOR: 3.51; 95% confidence interval [CI]: 1.14-11.01, P = .03) in the CHANCE study. This association was confirmed in our cross-sectional analysis (WashU/Siteman study) where missing 25-28 teeth was associated with an increased risk of alveolar ridge compared to tongue cancer (aOR: 4.60; 95% CI: 1.97-11.10, P = .001).

CONCLUSIONS

This study suggests an association between poor dental health and risk of alveolar ridge cancer independent of smoking, alcohol use, age, race, and sex. Future prospective and translational studies are needed to confirm this association and elucidate the mechanism of dental disease in alveolar ridge malignancies.

TGF-β Signaling in Progression of Oral Cancer

Oral cancer is a common malignancy worldwide, accounting for 1.9% to 3.5% of all malignant tumors. Transforming growth factor β (TGF-β), as one of the most important cytokines, is found to play complex and crucial roles in oral cancers. It may act in a pro-tumorigenic and tumor-suppressive manner; activities of the former include cell cycle progression inhibition, tumor microenvironment preparation, apoptosis promotion, stimulation of cancer cell invasion and metastasis, and suppression of immune surveillance. However, the triggering mechanisms of these distinct actions remain unclear. This review summarizes the molecular mechanisms of TGF-β signal transduction, focusing on oral squamous cell and salivary adenoid systemic carcinomas as well as keratocystic odontogenic tumors. Both the supporting and contrary evidence of the roles of TGF-β is discussed. Importantly, the TGF-β pathway has been the target of new drugs developed in the past decade, some having demonstrated promising therapeutic effects in clinical trials. Therefore, the achievements of TGF-β pathway-based therapeutics and their challenges are also assessed. The summarization and discussion of the updated knowledge of TGF-β signaling pathways will provide insight into the design of new strategies for oral cancer treatment, leading to an improvement in oral cancer outcomes.

The Role of IL-17 in the Pathogenesis of Oral Squamous Cell Carcinoma

Elucidating the inflammatory mechanisms underlying formation and progression of oral squamous cell carcinoma (OSCC) is crucial for discovering new targeted therapeutics. The proinflammatory cytokine IL-17 has proven roles in tumor formation, growth, and metastasis. The presence of IL-17 is demonstrated in both in vitro and in vivo models, and in OSCC patients, is mostly accompanied by enhanced proliferation and invasiveness of cancer cells. Here we review the known facts regarding the role of IL-17 in OSCC pathogenesis, namely the IL-17 mediated production of proinflammatory mediators that mobilize and activate myeloid cells with suppressive and proangiogenic activities and proliferative signals that directly induce proliferation of cancer cells and stem cells. The possibility of a potential IL-17 blockade in OSCC therapy is also discussed.

Inhibition of the CCR6-CCL20 axis prevents regulatory T cell recruitment and sensitizes head and neck squamous cell carcinoma to radiation therapy

BACKGROUND

 Radioresistance of HNSCCs remains a major challenge for effective tumor control. Combined radiotherapy (RT) and immunotherapy (IT) treatment improved survival for a subset of patients with inflamed tumors or tumors susceptible to RT-induced inflammation. To overcome radioresistance and improve treatment outcomes, an understanding of factors that suppress anti-tumor immunity is necessary. In this regard, regulatory T cells (Tregs) are critical mediators of immune suppression in HNSCCs. In this study, we investigated how radiation modulates Treg infiltration in tumors through the chemokine CCL20. We hypothesized that radiation induces CCL20 secretion resulting in Treg infiltration and suppression of anti-tumor immunity.

METHODS

 Human and mouse HNSCC cell lines with different immune phenotypes were irradiated at doses of 2 or 10 Gy. Conditioned media, RNA and protein were collected for assessment of CCL20. qPCR was used to determine CCL20 gene expression. In vivo, MOC2 cells were implanted into the buccal cavity of mice and the effect of neutralizing CCL20 antibody was determined alone and in combination with RT. Blood samples were collected before and after RT for analysis of CCL20. Tumor samples were analyzed by flow cytometry to determine immune infiltrates, including CD8 T cells and Tregs. Mass-spectrometry was performed to analyze proteomic changes in the tumor microenvironment after anti-CCL20 treatment.

RESULTS

 Cal27 and MOC2 HNSCCs had a gene signature associated with Treg infiltration, whereas SCC9 and MOC1 tumors displayed a gene signature associated with an inflamed TME. In vitro, tumor irradiation at 10 Gy significantly induced CCL20 in Cal27 and MOC2 cells relative to control. The increase in CCL20 was associated with increased Treg migration. Neutralization of CCL20 reversed radiation-induced migration of Treg cells in vitro and decreased intratumoral Tregs in vivo. Furthermore, inhibition of CCL20 resulted in a significant decrease in tumor growth compared to control in MOC2 tumors. This effect was further enhanced after combination with RT compared to either treatment alone.

CONCLUSION

 Our results suggest that radiation promotes CCL20 secretion by tumor cells which is responsible for the attraction of Tregs. Inhibition of the CCR6-CCL20 axis prevents infiltration of Tregs in tumors and suppresses tumor growth resulting in improved response to radiation.

Tumor-Infiltrating CD4+ Central Memory T Cells Correlated with Favorable Prognosis in Oral Squamous Cell Carcinoma

OBJECTIVE

Oral squamous cell carcinoma (OSCC) is the most frequent oral malignancy with a poor prognosis, in which tumor-infiltrating immune cells may play a critical role. Therefore, our study aims to screen potential immune cells and immune-related genes for predicting OSCC prognosis.

METHODS

A total of 310 OSCC patients with full transcriptional data and clinical characteristics were extracted from the TCGA database. Then, we obtained their abundance of tumor-infiltrating immune cells on TIMER 2.0 and analyzed them using xCell method. Univariate and multivariate Cox regressions were applied successively to identify the immune cells associated with overall survival of OSCC patients. Furthermore, we screened the prognostic genes that related to the identified immune cells and validated their expressions by immunohistochemistry.

RESULTS

CD4+ central memory T (TCM) cell was recognized as the sole independent immune cell correlated with OSCC prognosis (p = 0.0085). A novel nomogram based on CD4+ TCM cell abundance was established for predicting the prognosis of OSCC patients, with calibration plots showing good performance for 1-, 3-, 5-year overall survival. Thirty-four related prognostic genes were screened according to the differential abundance of CD4+ TCM cell infiltration. In immunohistochemistry analysis, DEFB1 showed a significant positive relationship with the density of CD4+ TCM cells (p = 0.0075).

CONCLUSION

CD4+ central memory T cell was proposed as an independent prognostic biomarker for OSCC patients. DEFB1 might positively regulate the abundance of tumor-infiltrating CD4+ TCM cells, thus improving OSCC prognosis. Our findings may provide a new insight into better prognosis prediction and precise medicine for OSCC.

Deciphering the Role of Regulatory CD4 T Cells in Oral and Oropharyngeal Cancer: A Systematic Review

Background: Recruiting regulatory CD4 T cells (Tregs) into the tumor microenvironment is an important tumor escape mechanism. Diminishing these suppressive cells is therefore one of the targets of cancer immunotherapy. Selective depletion of Tregs has proven successful in enhancing anti-tumor immunity and therapeutic efficacy in multiple tumor types. However, the role of Tregs in oral/oropharyngeal cancers is unclear with conflicting evidence regarding the effect of these suppressive cells on tumor prognosis. In this study, we sought to review the role of Tregs in oral/oropharyngeal cancer with the aim of deciphering the controversy regarding their effect on tumor progression and prognosis.

Methods: A systematic review of the literature pertaining to the role of Tregs in oral/oropharyngeal cancer was performed using Scopus, Embase, and PubMed. Forty-five records were deemed eligible and data describing methodology of Treg detection, tumor type, and association with prognosis were extracted.

Results: Of the 45 eligible manuscripts accepted for this systematic review, thirty-nine studies reported data from human subjects while the remaining studies focused on animal models. Sixteen studies were carried out using peripheral blood samples, while samples from the tumor site were analyzed in 18 studies and 11 studies assessed both blood and tumor samples. The transcriptional factor, Foxp3, was the most commonly used marker for Treg identification (38/45). The findings of 25 studies suggested that an increase in Tregs in the tumor microenvironment and/or peripheral blood was associated with poorer prognosis. These conclusions were attributed to the suppression of immune responses and the consequent tumor progression. Conversely, nine studies showed an increase in Tregs in peripheral blood and/or tumor microenvironment was related to a favorable prognosis, particularly in the presence of human papilloma virus (HPV), the status of which was only assessed in 11 studies.

Conclusions: This review underlines the importance of host immunity in the behavior of oral/oropharyngeal cancer. Furthermore, we report an apparent lack of clarity regarding the true role Tregs play in oral/oropharyngeal cancer progression which could be attributed to inconsistent detection techniques of Tregs. Our results therefore highlight the need for clearer methodologies and more robust phenotyping when defining Tregs.

Phenotypic and Functional Characteristics of Th17 (CD4+IL17A+) Cells in Human Oral Squamous Cell Carcinoma and Its Clinical Relevance

Recent studies have suggested an important role of T helper 17 (Th17) cells in tumor biology however, their phenotypic and functional aspects are poorly understood in context with oral cancer. We therefore, investigated the various phenotypic and functional markers of Th17 cells elucidating their relevance in oral squamous cell carcinoma (OSCC). Multi-color flow cytometry (FACs) was used to analyze the frequency and different markers of circulating Th17 cells ex vivo in peripheral blood mono-nuclear cells (PBMCs) from 69 OSCC patients and 35 healthy controls. Percent Mean ± SEM of different types of cells were compared between the two groups using Mann-Whitney U test. We found significantly (p < 0.0001) increased frequency of Th17 cells in patients as compared to controls. These cells were found to express CCR6 profoundly but not CXCR4, CD62L, and CCR7 as chemokine receptors. Additionally, it expressed HLA-DR, CD69, and CD25 moderately but CD28 and CD161 highly. The cytokine profiling revealed 3 subsets namely Th17/1 (IL17A⁺IFNγ⁺), Th17/inflammatory (IL17A⁺IL8⁺), and Th17/2 (IL17A⁺IL4⁺) which were found to be elevated in patients as compared to controls. The early stage patients had a shift toward Th17/1 type and vice versa. Our results suggest that Th17 cells may have effector immune functions in oral cancer immunity through CCR6, CD161, HLA-DR, CD69, CD28 receptors and inducing Th17/1 type of cells expressing polyfunctional antitumor IFNγ cytokine. Thus, novel immune-boosting regimens based on enhancement of Th17 cells in oral cancer patients may provide therapeutic benefits in them.

Oral inflammation promotes oral squamous cell carcinoma invasion

Oral squamous cell carcinoma (OSCC) represents 95% of oral malignancies and invasion, and metastasis underlies disease morbidity and mortality. We recently established a direct link between oral inflammation and cancer invasion by showing that neutrophils increase OSCC invasion through a tumor necrosis factor (TNFα)-dependent mechanism. The objective of this study was to characterize OSCC-associated inflammation and to determine the molecular mechanisms underlying inflammation-mediated OSCC invasion. Our results showed a significant increase in neutrophil infiltration, the neutrophil-to-lymphocyte ratio in the OSCC microenvironment and increased inflammatory markers, particularly TNFα in saliva. We performed next-generation sequencing of the TNFα-treated OSCC cells and showed marked overexpression of over 180 genes distributed among clusters related to neutrophil recruitment, invasion, and invadopodia. At the molecular level, TNFα treatment increased phosphoinositide 3-kinase (PI3K)-mediated invadopodia formation and matrix metalloproteinase (MMP)-dependent invasion. We show here that TNFα promotes a pro-inflammatory and pro-invasion phenotype leading to the recruitment and activation of inflammatory cells in a paracrine mechanism. Increased TNFα in the tumor microenvironment tips the balance towards invasion leading to decreased overall survival and disease-free survival. This represents a significant advancement of oral cancer research and will support new treatment approaches to control OSCC invasion and metastasis.

Enrichment of Human CCR6+ Regulatory T Cells with Superior Suppressive Activity in Oral Cancer

Human oral squamous cell carcinoma (OSCC) constitutes an inflammatory microenvironment enriched with chemokines such as CCL20, which promote cancer cell invasion and tumor progression. We found that in OSCC there is a correlation between the expression of CCL20 and FOXP3 mRNA. Therefore, we hypothesized that OSCC may favor the recruitment and retention of regulatory T (Treg) cells that express the CCL20 receptor, CCR6. Interestingly, most (∼60%) peripheral blood Treg cells express CCR6, and CCR6⁺ Treg cells exhibit an activated effector/memory phenotype. In contrast, a significant portion (>30%) of CCR6^- Treg cells were found to be CD45RA⁺ naive Treg cells. Compared to CCR6^- naive or memory Treg cells, CCR6⁺ Treg cells exhibit stronger suppressive activity and display higher FOXP3 expression along with lower methylation at the Treg-specific demethylated region of the FOXP3 gene. This predominance of CCR6⁺ Treg cells was also found in the draining lymph nodes and tumor-infiltrating lymphocytes of OSCC patients with early or late clinical staging. Moreover, CCR6⁺ Treg cells isolated from tumor-infiltrating lymphocytes or draining lymph nodes maintained similar phenotypic and suppressive characteristics ex vivo as did their counterparts isolated from peripheral blood. These results suggest that CCR6 marks activated effector or memory Treg phenotypes with superior suppressive activity in humans.

Role of LAP+CD4+ T cells in the tumor microenvironment of colorectal cancer

AIM

To investigate the abundance and potential functions of LAP⁺CD4⁺ T cells in colorectal cancer (CRC).

METHODS

Proportions of LAP⁺CD4⁺ T cells were examined in peripheral blood and tumor/paratumor tissues of CRC patients and healthy controls using flow cytometry. Expression of phenotypic markers such as forkhead box (Fox)p3, cytotoxic T-lymphocyte-associated protein (CTLA)-4, chemokine CC receptor (CCR)4 and CCR5 was measured using flow cytometry. LAP^-CD4⁺ and LAP⁺CD4⁺ T cells were isolated using a magnetic cell-sorting system and cell purity was analyzed by flow cytometry. Real-time quantitative polymerase chain reaction was used to measure expression of cytokines interleukin (IL)-10 and transforming growth factor (TGF)-β.

RESULTS

The proportion of LAP⁺CD4⁺ T cells was significantly higher in peripheral blood from patients (9.44% ± 3.18%) than healthy controls (1.49% ± 1.00%, P < 0.001). Among patients, the proportion of LAP⁺CD4⁺ T cells was significantly higher in tumor tissues (11.76% ± 3.74%) compared with paratumor tissues (3.87% ± 1.64%, P < 0.001). We also observed positive correlations between the proportion of LAP⁺CD4⁺ T cells and TNM stage (P < 0.001), distant metastasis (P < 0.001) and serum level of carcinoembryonic antigen (P < 0.05). Magnetic-activated cell sorting gave an overall enrichment of LAP⁺CD4⁺ T cells (95.02% ± 2.87%), which was similar for LAP^-CD4⁺ T cells (94.75% ± 2.76%). In contrast to LAP^-CD4⁺ T cells, LAP⁺CD4⁺ T cells showed lower Foxp3 expression but significantly higher levels of CTLA-4, CCR4 and CCR5 (P < 0.01). LAP⁺CD4⁺ T cells expressed significantly larger amounts of IL-10 and TGF-β but lower levels of IL-2, IL-4, IL-17 and interferon-γ, compared with LAP^-CD4⁺ T cells.

CONCLUSION

LAP⁺CD4⁺ T cells accumulated in the tumor microenvironment of CRC patients and were involved in immune evasion mediated by IL-10 and TGF-β.

Prognostic Value of Tumor-Infiltrating Lymphocytes for Patients With Head and Neck Squamous Cell Carcinoma

BACKGROUND: The prognostic value of tumor-infiltrating lymphocytes (TILs) in head and neck squamous cell carcinoma (HNSCC) remains controversial. Additionally, there is no standardized approach or cutoff value for evaluating TIL levels. The aim of this study was to establish a feasible method and criterion to assess TIL levels for future clinical practice and research use and to explore the relationship between TIL levels and prognosis. PATIENTS AND METHODS: This retrospective cohort study reviewed the records and pathological sections of 202 patients with HNSCC who were surgically treated at Beijing Stomatological Hospital, Capital Medical University, from January 1998 to January 2011. The predictor variable was the TIL level. The main outcome assessment parameters were disease-free survival (DFS) and disease-specific survival (DSS). RESULT: The T stage (P = .008), smoking history (P = .042), alcohol history (P = .048), need for radiotherapy (P = .012) and microscopic extracapsular spread (ECS) (P = .012) were associated with the TIL level. A cutoff value equal to 70% could be taken as a threshold for TIL assessment, with a TIL level higher than 70% associated with a better prognosis (DFS rate: 51.9%, P = .018; DSS rate: 59.3%, P = .049). The Cox regression model showed that the TIL level was an independent prognostic factor for DFS (hazard ratio (HR): 0.786, 95% CI: 0.618-0.999, P = .049). CONCLUSION: The TIL level is closely related to the prognosis of patients with HNSCC. A threshold value of 70% is appropriate for TIL assessment, as patients with a TIL level higher than 70% show a better prognosis. Thus, the TIL level might serve as an independent predictor for HNSCC recurrence.

Multiple cells express interleukin 17 in oral squamous cell carcinoma

BACKGROUND

Interleukin (IL)-17 is a pro-inflammatory cytokine with pro- and antitumour effects. The aim of this study was to investigate the presence and potential sources of IL-17 in oral squamous cell carcinoma (OSCC).

METHODS

Immunohistochemistry was used to label and compare IL-17⁺ cells in the tissue sections of OSCC and inflammatory controls (IC), n = 14 for both. In OSCC, the comparison was made between the number of IL-17⁺ cells in the tumoral islands (TI), tumour-stroma interface (TS) and more distant stroma (DS). Cells expressing IL-17 were identified using double-labelling immunofluorescence and examined using laser scanning microscopy. The production of IL-17 from tumour cells was determined in the culture supernatants of OSCC cell lines, SCC4, SCC15 and SCC25, using sandwich ELISA.

RESULTS

Significantly more IL-17⁺ cells were observed in OSCC compared with IC (Mann-Whitney, P < 0.0001). In OSCC, the numbers of IL-17⁺ cells were not significantly different in three compartments, TI, TS and DS (one-way ANOVA, P > 0.05). However, the TI had significantly fewer IL-17⁺ cells than the combined stroma (both TS and DS together, Mann-Whitney, P < 0.01). Laser scanning microscopy revealed helper T cells, cytotoxic T cells, macrophages and mast cells co-expressed IL-17. ELISA experiments did not detect IL-17 in the supernatants of OSCC cell lines.

CONCLUSIONS

Although the tumour cells themselves did not express IL-17, a range of cell types did, suggesting multiple cellular sources for IL-17 in OSCC. The spatial distribution of IL-17⁺ cells suggests specific interactions with cells within the tumour microenvironment, implying that IL-17⁺ cells are likely to play a role in the pathogenesis of OSCC.

The dual role of iNOS in cancer

Nitric oxide (NO) is one of the 10 smallest molecules found in nature. It is a simple gaseous free radical whose predominant functions is that of a messenger through cGMP. In mammals, NO is synthesized by the enzyme nitric oxide synthase (NOS) of which there are three isoforms. Neuronal (nNOS, NOS1) and endothelial (eNOS, NOS3) are constitutive calcium-dependent forms of the enzyme that regulate neural and vascular function respectively. The third isoform (iNOS, NOS2), is calcium-independent and is inducible. In many tumors, iNOS expression is high, however, the role of iNOS during tumor development is very complex and quite perplexing, with both promoting and inhibiting actions having been described. This review will aim to summarize the dual actions of iNOS-derived NO showing that the microenvironment of the tumor is a contributing factor to these observations and ultimately to cellular outcomes.

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NO is pro- and anti-tumorigenic. High concentrations of NO maybe anti-tumorigenic.

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iNOS produces high concentrations of NO and relates to tumor growth or its inhibition.

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iNOS is associated with cytotoxicity, apoptosis and bystander anti-tumor effects.

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Tumor- and stromal-iNOS, and the ‘cell situation’ contribute to anti or pro-tumor effects.

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Dual role of iNOS is influenced by the cell situation and is environment dependent.

CD11b+Ly6G+ cells inhibit tumor growth by suppressing IL-17 production at early stages of tumorigenesis

Neutrophils are important innate immune cells involved in microbial clearance at the sites of infection. However, their role in cancer development is unclear. We hypothesized that neutrophils mediate antitumor effects in early tumorigenesis. To test this, we first studied the cytotoxic effects of neutrophils in vitro. Neutrophils were cytotoxic against tumor cells, with neutrophils isolated from tumor-bearing mice trending to have increased cytotoxic activities. We then injected an ELR+ CXC chemokine-producing tumor cell line into C57BL/6 and Cxcr2−/− mice, the latter lacking the receptors for neutrophil chemokines. We observed increased tumor growth in Cxcr2−/− mice. As expected, tumors from Cxcr2−/− mice contained fewer neutrophils. Surprisingly, these tumors also contained fewer CD8⁺ T cells, but more IL-17-producing cells. Replenishment of functional neutrophils was correlated with decreased IL-17-producing cells, increased CD8⁺ T cells, and decreased tumor size in Cxcr2−/− mice, while depletion of neutrophils in C57BL/6 mice showed the opposite effects. Results from a non-ELR+ CXC chemokine producing tumor further supported that functional neutrophils indirectly mediate tumor control by suppressing IL-17A production. We further studied the correlation of IL-17A and CD8⁺ T cells in vitro. IL-17A suppressed proliferation and IFNγ production of CD8⁺ T cells, while CD11b+Ly6G+ neutrophils did not suppress CD8⁺ T cell function. Taken together, these data demonstrate that, while neutrophils could control tumor growth by direct cytotoxic effects, the primary mechanism by which neutrophils exert antitumor effects is to regulate IL-17 production, through which they indirectly promote CD8⁺ T cell responses.

Expression of prostaglandin E2 prostanoid receptor EP2 and interleukin-1β in laryngeal carcinoma - preliminary study

Aim of the study

Expression of EP2 protein, the prostaglandin E₂ (PGE₂) receptor, produced by tumour microenvironment inflammatory cells as well as tumour cells, may promote cellular proliferation and growth in an autocrine and paracrine fashion. The phenomenon involving these proteins is regulated by interleukin 1β (IL-1β). Many researchers indicate a connection of EP2 and IL-1β in various types of neoplasms with higher tumour progression and poor prognosis. The aim of this study was to analyse the EP2 expression within laryngeal carcinoma tissue and IL-1β levels in peripheral blood mononuclear cell supernatants and to find relationships between clinicomorphological features.

Material and methods

A group of 50 patients with verified squamous cell laryngeal carcinoma was analysed in this study. The pathological evaluation included pTNM depth of invasion according to tumour front grading criteria. Immunohistochemical analysis for membranous staining of EP2 in tumour tissues was used. The IL-1β expression was determined by enzyme-linked immunosorbent assay (ELISA).

Results

Increased EP2 expression in carcinoma cells was confirmed for more advanced tumours (pT3-pT4 vs. pT1-pT2, p < 0.0001 and pN1-3 vs. pN0, p = 0.02). Tumours with the highest aggressiveness identified by deeper invasion of submucosa or cartilage were characterised by the highest expression of EP2 (p < 0.0001). In laryngeal carcinomas characterised by a lower differentiation the highest EP2 expression in tumour cells was noted (p = 0.009). A positive relationship between IL-1β expression and the presence of lymph node metastases was also confirmed (p = 0.04).

Conclusions

The study indicates the potential effect of EP2 receptor and IL-1β on tumour progression in laryngeal carcinoma.

Activated human valvular interstitial cells sustain interleukin-17 production to recruit neutrophils in infective endocarditis

The mechanisms that underlie valvular inflammation in streptococcus-induced infective endocarditis (IE) remain unclear. We previously demonstrated that streptococcal glucosyltransferases (GTFs) can activate human heart valvular interstitial cells (VIC) to secrete interleukin-6 (IL-6), a cytokine involved in T helper 17 (Th17) cell differentiation. Here, we tested the hypothesis that activated VIC can enhance neutrophil infiltration through sustained IL-17 production, leading to valvular damage. To monitor cytokine and chemokine production, leukocyte recruitment, and the induction or expansion of CD4(+) CD45RA(-) CD25(-) CCR6(+) Th17 cells, primary human VIC were cultured in vitro and activated by GTFs. Serum cytokine levels were measured using an enzyme-linked immunosorbent assay (ELISA), and neutrophils and Th17 cells were detected by immunohistochemistry in infected valves from patients with IE. The expression of IL-21, IL-23, IL-17, and retinoic acid receptor-related orphan receptor C (Rorc) was upregulated in GTF-activated VIC, which may enhance the proliferation of memory Th17 cells in an IL-6-dependent manner. Many chemokines, including chemokine (C-X-C motif) ligand 1 (CXCL1), were upregulated in GTF-activated VIC, which might recruit neutrophils and CD4(+) T cells. Moreover, CXCL1 production in VIC was induced in a dose-dependent manner by IL-17 to enhance neutrophil chemotaxis. CXCL1-expressing VIC and infiltrating neutrophils could be detected in infected valves, and serum concentrations of IL-17, IL-21, and IL-23 were increased in patients with IE compared to healthy donors. Furthermore, elevated serum IL-21 levels have been significantly associated with severe valvular damage, including rupture of chordae tendineae, in IE patients. Our findings suggest that VIC are activated by bacterial modulins to recruit neutrophils and that such activities might be further enhanced by the production of Th17-associated cytokines. Together, these factors can amplify the release of neutrophilic contents in situ, which might lead to severe valvular damage.

Preferential recruitment of Th17 cells to cervical cancer via CCR6-CCL20 pathway

Our previous studies suggest that Th17 cells accumulate within tumor tissues and correlate with recurrence of cervical cancer patients. However, the source of the increased tumor-infiltrating Th17 cells remains poorly understood. We investigated the prevalence, phenotype and trafficking property of Th17 cells in patients with cervical cancer. Our results showed that Th17 cells highly aggregated within tumor tissues in an activated phenotype with markedly increased expression of CCR6. Correspondingly, level of CCL20 in the tumor tissues was significantly higher than that in non-tumor and normal control tissues, and strongly positively associated with Th17 cells. Further, in vitro migration assay showed CCL20 had effective chemotaxis to circulating Th17 cells. In conclusion, Th17 cells are recruited into tumor tissues preferentially through CCR6-CCL20 pathway, which can serve as a novel therapeutic target for cervical cancer.

Increased interleukin-17 transcripts in peripheral blood mononuclear cells, a link between T-helper 17 and proinflammatory responses in bladder cancer

Background:

Interleukin (IL)-17-producing CD4+ T helper (Th17) cells thatare known by producing IL-17 have recently been defined as a unique subset of proinflammatory helper cells. IL-17 is an inflammatory cytokine with robust effect on many cells and it can play important roles in pathogenesis of diverse groups of immune-mediated diseases.

Objectives:

The aim of this case-control study was to determine the gene expression of IL-6, IL-17, and transforming growth factor beta (TGF-β) in Iranian patients with bladder cancer.

Patients and Methods:

Blood samples were collected from 37 patients with bladder cancer and 37 healthy individuals with no history of malignancies or autoimmune disorders, based of simple sampling. The expression of IL-6, IL-17, and TGF-β were measured by quantitative real-time polymerase chain reaction (qRT-PCR).

Results:

The mean of IL-17 transcripts was significantly higher in patients with bladder cancer compared with healthy individuals (0.33 ± 0.06 vs. 0.42 ± 0.14, ) (P = 0.04), but their TGF-β was lower (12.53 ± 8.41 vs. 54.94 ± 17.95, ) (P = 0.04). However, the IL-6 transcripts level was similar in both groups (5.34 ± 2.40 vs. 8.07 ± 3.28, ) (P > 0.05) and there was not any significant difference between the noted cytokines expressions among patients with different stages and grades.

Conclusions:

As most of the cases studied in this investigation were in stages I and II, IL-17 as a prominent proinflammatory cytokine may play an important role in recruiting and infiltrating of antitumor immune responses in early stages of bladder cancer. Furthermore, it can be used as predictor for the clinical stage and prognosis of cancers such as bladder carcinoma.

Tumor infiltrating lymphocytes (TIL) and prognosis in oral cavity squamous carcinoma: a preliminary study

OBJECTIVES

Tumor infiltrating lymphocytes (TILs) in the microenvironment reflect may tumor biology and predict outcome. We previously demonstrated that infiltrates of CD4, CD8, and FoxP3 positive lymphocytes were associated with HPV-status and survival in oropharyngeal cancers. To determine if TILs were of prognostic importance in oral cancer, TIL levels were evaluated retrospectively in 52 oral cancer patients treated with surgery and correlations with outcome determined.

METHODS

Complete TIL and clinical data were available for 39 patients. Levels of CD4, CD8, FoxP3 (Treg), CD68 and NK cells were assessed by immunohistochemistry in tumor cores on a tissue microarray. Associations with clinical variables, tobacco and alcohol use and histologic features were assessed using Spearman correlation coefficient and the non-parametric Kruskal-Wallis testing. Time-to-event outcomes were determined using univariate and multivariate Cox models. Median follow up was 60 months.

RESULTS

The ratio of CD4/CD8 (p=.01) and CD8 infiltrates (p=.05) were associated with tumor recurrence but not overall survival. Lower CD4 infiltrates were associated with alcohol use (p=.005) and poor tumor differentiation (p=.02). Interestingly, higher levels of CD68+ macrophages were found associated with positive nodes (p=.06) and poorer overall survival (p=.07). Overall and DSS survival were significantly shorter for patients with positive nodes, extracapsular spread, or perineural invasion.

CONCLUSION

Infiltrating immune cell levels in oral cavity cancer appear influenced by health behaviors and tumor characteristics. In contrast to oropharynx cancer, infiltrates of CD68 positive tumor associated macrophages may contribute to metastatic behavior and outcome in advanced oral cavity carcinoma.

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.

Skewed distribution of IL-7 receptor-α-expressing effector memory CD8+ T cells with distinct functional characteristics in oral squamous cell carcinoma

CD8⁺ T cells play important roles in anti-tumor immunity but distribution profile or functional characteristics of effector memory subsets during tumor progression are unclear. We found that, in oral squamous carcinoma patients, circulating CD8⁺ T cell pools skewed toward effector memory subsets with the distribution frequency of CCR7⁻CD45RA⁻CD8⁺ T cells and CCR7⁻ CD45RA⁺CD8⁺ T cells negatively correlated with each other. A significantly higher frequency of CD127^lo CCR7⁻CD45RA⁻CD8⁺ T cells or CCR7⁻CD45RA⁺CD8⁺ T cells among total CD8⁺ T cells was found in peripheral blood or tumor infiltrating lymphocytes, but not in regional lymph nodes. The CD127^hi CCR7⁻CD45RA⁻CD8⁺ T cells or CCR7⁻CD45RA⁺CD8⁺ T cells maintained significantly higher IFN-γ, IL-2 productivity and ex vivo proliferative capacity, while the CD127^lo CCR7⁻CD45RA⁻CD8⁺ T cells or CCR7⁻CD45RA⁺CD8⁺ T cells exhibited higher granzyme B productivity and susceptibility to activation induced cell death. A higher ratio of CCR7⁻CD45RA⁺CD8⁺ T cells to CCR7⁻CD45RA⁻CD8⁺ T cells was associated with advanced cancer staging and poor differentiation of tumor cells. Therefore, the CD127^lo CCR7⁻CD45RA⁻CD8⁺ T cells and CCR7⁻CD45RA⁺CD8⁺ T cells are functionally similar CD8⁺ T cell subsets which exhibit late differentiated effector phenotypes and the shift of peripheral CD8⁺ effector memory balance toward CCR7⁻CD45RA⁺CD8⁺ T cells is associated with OSCC progression.

Anti-cancer versus cancer-promoting effects of the interleukin-17-producing T helper cells

Research on T helper 17 (Th17) cells with regard to immunoediting has revealed elusive results. Whereas enhanced Th17 response and related molecules such as interleukin (IL)-17, IL-21, IL-22, IL-23 and STAT3 accompanied tumor induction and progression, finding that tumor growth/stage was negatively correlated with increased infiltration of Th17 cells in the tumor mass has prompted elucidation of various antitumor mechanisms elicited by Th17 and their related molecules. The pro-tumor efficacy of Th17 response included promotion of neutrophilia and induction of angiogenic (e.g. VEGF, MMP2 and MMP9) and anti-apoptotic factors (e.g. Bcl-XL), as well as expansion and activation of myeloid-derived suppressor cells, which facilitate generation of tumor-specific regulatory T cells. Other tumor immunogenic settings revealed anti-tumor pathways including induction of cytotoxic activity, expression of MHC antigens, the ability Th17 cells to reside within the tumor, and to convert into IFN-γ producers. Notably, Th17 cell related molecules exert indirect pro- or anti-tumor effects via inducing viral persistence or mediating protective mechanisms against bacterial and viral infection. Herein, the recent literature revealing such immunoediting events mediated by Th17 cells and their associated molecules as delivered by various experimental regimens and observed in cancer patient are revised, with a focus on some proposed anti-cancer therapies.

Correlation between circulating myeloid-derived suppressor cells and Th17 cells in esophageal cancer

AIM: To perform a comprehensive investigation into the potential correlation between circulating myeloid-derived suppressor cells (MDSCs) and Th17 cells in esophageal cancer (ECA).

METHODS: A total of 31 patients newly diagnosed with ECA and 26 healthy subjects were included in the current study. The frequencies of MDSCs and Th17 cells in peripheral blood were determined by flow cytometry. The mRNA expression of cytokines, arginase 1 (Arg1) and inducible NO synthase (iNOS) in peripheral blood mononuclear cells (PBMCs) and plasma Arg1 were assessed by real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively.

RESULTS: There was an increased prevalence of MDSCs in the peripheral blood from ECA patients (15.21% ± 2.25%) when compared with healthy control (HC) (1.10% ± 0.12%, P < 0.0001). The plasma levels of Arg1 in ECA patients were significantly higher than those in HC (28.28 ± 4.10 ng/mL vs 9.57 ± 1.51 ng/mL, P = 0.0003). iNOS mRNA levels in the peripheral blood of ECA patients also showed a threefold increase compared with HC (P = 0.0162). The frequencies of Th17 cells (CD4⁺IL-17A⁺) were significantly elevated in ECA patients versus HC (3.50% ± 0.33% vs 1.82% ± 0.19%, P = 0.0001). Increased mRNA expression of IL-17 and ROR-γt was also observed in ECA patients compared with HC (P = 0.0041 and P = 0.0004, respectively), while the mRNA expression of IL-6 and tumor necrosis factor-α (TNF-α) showed significant decreases (P = 0.0049 and P < 0.0001, respectively). No obvious correlations were found between the frequencies of MDSCs and Th17 cells in the peripheral blood from ECA patients(r = -0.1725, P = 0.3534). Arg1 mRNA levels were positively correlated with levels of IL-6 (r = 0.6404, P = 0.0031) and TNF-α (r = 0.7646, P = 0.0001). Similarly, iNOS mRNA levels were also positively correlated with levels of IL-6 (r = 0.6782, P = 0.0007) and TNF-α (r = 0.7633, P < 0.0001).

CONCLUSION: This study reveals the relationship between circulating MDSCs and Th17 cells, which may lead to new immunotherapy approaches for ECA based on the associated metabolites and cytokines.

CD25+ T cell depletion impairs murine squamous cell carcinoma development via modulation of antitumor immune responses

Squamous cell carcinoma (SCC) constitutes a microenvironment that could modulate the antitumor immune response. Also, tumor-infiltrating lymphocytes are believed to play complex regulatory roles in antitumor immunity against SCC. The presence of regulatory T cells (Tregs) has been associated with the suppression of tumor-reactive T cells. However, the underlying mechanism for this T cell dysfunction is not clear. We used a multistage model of SCC to examine the role of Treg cells during tumor development. 7,12-dimethylbenz[a]-anthracene/phorbol 12-myristate 13-acetate treatment and systemic depletion of Treg cells using an anti-CD25 monoclonal antibody (PC61) resulted in a decrease in the number and incidence of papilloma. Furthermore, CD25 depletion increased the proportion of CD8(+) and CD4(+) T cells that were isolated from tumor lesions. The levels of interleukin (IL)-1β, IL-10, IL-12, IL-13, interferon-γ, transforming growth factor-β and tumor necrosis factor-α, but not IL-17, were increased in the tumor microenvironment after Treg depletion. Therefore, our results indicated involvement of CD25(+) T cells in SCC development and in the suppression of the inflammatory immune response.

CpG oligonucleotides induce the differentiation of CD4(+)Th17 cells by triggering plasmacytoid dendritic cells in adoptively cell transfer immunotherapy

Our previous data showed that CpG-ODNs could significantly enhance the anti-tumor efficacy of adoptively cell transfer (ACT), which was closely correlated to accumulation of Th17 cells in tumor mass. Here we further investigated that CpG-ODNs had no significant effect on the migration and proliferation capacity of Th17 cells in tumor mass. Instead, we showed that CpG-ODNs could induce the differentiation of Th17 cells via dendritic cells (DCs) in tumor infiltrating lymphocytes (TILs). Notably, we found that plasmacytoid dendritic cells (pDCs), but not myeloid dendritic cells (mDCs), were responsible for the Th17 differentiation induced by CpG-ODNs via IL-6, TGF-β and IFN-α in vitro. Finally, we revealed that CpG-ODNs could stimulate pDCs to induce the differentiation of Th17 cells in vivo, which subsequently reduced the tumor size and prolonged the survival of tumor bearing nude mice. These data provided a novel insight into the mechanism of anti-tumor efficacy of CpG-ODNs based therapeutic strategy.

[Research advances on Th17 cells in tumor]

Th17细胞是近年来被鉴定出的一类新型CD4阳性T细胞亚群。与传统的Th1、Th2细胞不同，它以分泌IL-17为主要特征，并参与自身免疫性疾病和慢性炎症的发病过程。最近的证据表明Th17细胞也参与肿瘤免疫，然而这些细胞究竟是促进肿瘤的发展或是抑制肿瘤的发展尚不清楚。本综述总结了有关Th17细胞在肿瘤中作用的最新资料，分析Th17细胞在肿瘤中的特性和作用，以利于未来设计更有效的肿瘤治疗方案。

Increased lymphocyte infiltration in patients with head and neck cancer treated with the IRX-2 immunotherapy regimen

Twenty-seven subjects with squamous cell cancer of the head and neck received the neoadjuvant IRX-2 immunotherapy regimen prior to surgery in a Phase 2 trial. Pretreatment tumor biopsies were compared with the primary tumor surgical specimens for lymphocyte infiltration, necrosis and fibrosis, using hematoxylin and eosin stain and immunohistochemistry in 25 subjects. Sections were examined by three pathologists. Relative to pretreatment biopsies, increases in lymphocyte infiltration (LI) were seen using H and E or immunohistochemistry. CD3+ CD4+ T cells and CD20+ B cells were primarily found in the peritumoral stroma and CD3+ CD8+ T cells and CD68+ macrophages were mainly intratumoral. LI in the surgical specimens were associated with reductions in the primary tumor size. Improved survival at 5 years was correlated with high overall LI in the tumor specimens. Neoadjuvant IRX-2 immunotherapy regimen may restore immune responsiveness presumably by mobilizing tumor infiltrating effector lymphocytes and macrophages into the tumor.

Effect of moxibustion on mitochondrial ultrastructure and contents of mitochondrial enzymes in the intestinal epithelium of spleen-deficiency rats

AIM: To observe the effect of moxibustion on symptom scores, mitochondrial ultrastructure, contents of succinodehydrogenase (SDH) and cytochrome oxidase (CCO), expression of COX I in the jejunal epithelium of spleen-deficiency rats and to explore the mechanism by which moxibustion reinforces the spleen-stomach.

METHODS: Forty healthy Sprague-Dawley rats were randomly assigned into four groups: A (blank group; normal rats), B (model group; spleen-deficiency rats), C (moxibustion group; spleen-deficiency rats intragastrically given Sijunzi Decoction) and D (herbs group; spleen-deficiency rats receiving moxibustion at Zusanli, Zhongwan, Guanyuan, Pishu and Weishu points). An animal model of spleen-deficiency was established by intragastric administration of Chinese Rhubarb Infusion. Common symptoms were recorded. Mitochondrial ultrastructure of the jejunal epithelium was observed by electron microscopy. Enzyme-linked immunosorbent assay was used to detect the contents of SDH and CCO. The expression of COX I was detected by Western blot.

RESULTS: Compared to group A, symptom score increased significantly (P < 0.01), the contents of SDH and CCO and expression of COX I decreased significantly (P < 0.05 or 0.01), and the mitochondrial ultrastructure of the jejunal epithelium was terribly destroyed in group B. Compared to group B, the mitochondrial ultrastructure of the jejunal epithelium was only mildly destroyed, and the contents of SDH and CCO and expression of COX I increased significantly (0.387 ± 0.076, 0.343 ± 0.053 vs 0.277 ± 0.037; 0.246 ± 0.058, 0.231 ± 0.038 vs 0.167 ± 0.021; 0.941 ± 0.204, 1.040 ± 0.214 vs 0.481 ± 0.131, P < 0.05 or 0.01) in groups C and D. There were no significant differences in the above parameters between groups C and D.

CONCLUSION: Moxibustion could warm and reinforce the spleen-stomach and relieve symptoms of spleen-deficiency possibly by promoting the recovery of mitochondrial ultrastructure of the intestinal epithelium and increasing the contents of respiratory chain enzymes.

Insulin-like growth factor (IGF)-Ⅱ/IGF-ⅠR related signaling pathway and molecular targeted therapy for hepatocellular carcinoma

The insulin-like growth factor (IGF)-Ⅱ/IGF-Ⅰreceptor (IGF-ⅠR) related signaling pathway is associated with the development and progression of hepatocellular carcinoma (HCC). Hepatic IGF-Ⅱactivation can deliver a mitogenic signal to IGF-ⅠR to increase the tumorigenic potential of liver cells. Recently, a considerable amount of evidence suggests that targeted inhibition of IGF-Ⅱ and IGF-ⅠR could inhibit the proliferation of hepatoma cells. In this review, we summarize the interaction of IGF-Ⅱ and IGF-ⅠR in hepatocarcinogenesis and evaluate their potential use in molecular targeted therapy for hepatocellular carcinoma.

Role of nitric oxide in pancreas-duodenal transplantation in rats

AIM: To investigate the role of nitric oxide in ischemia-reperfusion injury and cell apoptosis following pancreas-duodenal transplantation in rats.

METHODS: A total of 168 SD rats were used in the study. Seventy-two female rats with diabetes induced by intraperitoneal injection of alloxan were used as donors, and 96 male rats were used as recipients. A rat model of pancreas-duodenal transplantation was developed using dual cannula technique. The 96 male rats were randomly divided into sham group, control group, L-Arg group, and L-NAME group, with 24 rats in each group. Rats of each group were randomly killed at 1 h, 3 h and 6 h. Serum nitric oxide and amylase levels were examined, and pancreatic injury was evaluated. The expression of iNOS in pancreatic tissue was detected by immunohistochemistry, and pancreatic cell apoptosis was evaluated by flow cytometry.

RESULTS: Serum nitric oxide and amylase, pancreas injury scores were significantly higher in the control group (1 h, 3 h, 6 h) than in the sham group (all P < 0.01). Serum nitric oxide was significantly higher and serum amylase and pancreas injury scores were significantly lower in the L-Arg group than in the control group (1 h, 3 h, 6 h) (all P < 0.01). Serum nitric oxide was significantly lower and serum amylase and pancreas injury scores were significantly higher in the L-NAME group than in the control group (all P < 0.01). The percentage of viable cells was significantly lower and apoptosis rate was significantly higher in the control group than in the sham group (all P < 0.01). The percentage of viable cells was significantly lower and apoptosis rate was significantly higher in the L-Arg and L-NAME groups than in the control group (all P < 0.01). The number of necrotic cells in the L-Arg group was lower than that in the control group but higher than that in the L-NAME group (all P < 0.01).

CONCLUSION: Nitric oxide plays a dual role in ischemia-reperfusion injury and cell apoptosis following pancreas-duodenal transplantation in rats.

Role of interaction between Th17 cells and commensal microbiota in the pathogenesis of inflammatory bowel disease

Inflammatory bowel disease (IBD) is an autoimmune disease whose etiology and pathogenesis remain incompletely understood. Th17 cells can secrete cytokines interleukin-17A and interleukin-17F, which play an important role in the pathogenesis of IBD. Some studies have proved that reduction of IL-17A and IL-17F can attenuate intestinal mucosal inflammation. Additionally, many studies reveal that the occurrence of IBD is correlated with commensal microbiota. Commensal microbiota can alter the number of Th17 cells in intestinal mucosa and cause abnormal intestinal mucosal immune responses. Elucidation of relationship between Th17 cells and commensal microbiota in intestinal mucosa is important for understanding the pathogenesis of IBD.

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.