The role of FoxP3+ regulatory T cells and IDO+ immune and tumor cells in malignant melanoma – an immunohistochemical study

Abstract Background FoxP3+ Regulatory T cells (Tregs) and indoleamine-2,3-dioxygenase (IDO) participate in the formation of an immunosuppressive tumor microenvironment (TME) in malignant cutaneous melanoma (CM). Recent studies have reported that IDO expression correlates with poor prognosis and greater Breslow’s depth, but results concerning the role of FoxP3+ Tregs in CM have been controversial. Furthermore, the correlation between IDO and Tregs has not been substantially studied in CM, although IDO is known to be an important regulator of Tregs activity. Methods We investigated the associations of FoxP3+ Tregs, IDO+ tumor cells and IDO+ stromal immune cells with tumor stage, prognostic factors and survival in CM. FoxP3 and IDO were immunohistochemically stained from 29 benign and 29 dysplastic nevi, 18 in situ -melanomas, 48 superficial and 62 deep melanomas and 67 lymph node metastases (LNMs) of CM. The number of FoxP3+ Tregs and IDO+ stromal immune cells, and the coverage and intensity of IDO+ tumor cells were analysed. Results The number of FoxP3+ Tregs and IDO+ stromal immune cells were significantly higher in malignant melanomas compared with benign lesions. The increased expression of IDO in melanoma cells was associated with poor prognostic factors, such as recurrence, nodular growth pattern and increased mitotic count. Furthermore, the expression of IDO in melanoma cells was associated with reduced recurrence˗free survival. We further showed that there was a positive correlation between IDO+ tumor cells and FoxP3+ Tregs. Conclusions These results indicate that IDO is strongly involved in melanoma progression. FoxP3+ Tregs also seems to contribute to the immunosuppressive TME in CM, but their significance in melanoma progression remains unclear. The positive association of FoxP3+ Tregs with IDO+ melanoma cells, but not with IDO+ stromal immune cells, indicates a complex interaction between IDO and Tregs in CM, which demands further studies.

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P02.08 The role of FoxP3+ regulatory T cells and IDO+ immune and tumor cells in malignant melanoma – an immunohistochemical study

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2021-itoc8.20 ◽

2021 ◽

Vol 9 (Suppl 1) ◽

pp. A10.2-A11

Author(s):

S Salmi ◽

A Lin ◽

B Hirschovits-Gerz ◽

M Valkonen ◽

N Aaltonen ◽

...

Keyword(s):

T Cells ◽

Prognostic Factors ◽

Regulatory T Cells ◽

Tumor Cells ◽

Immune Cells ◽

Immune Cell ◽

Positive Association ◽

Melanoma Cells ◽

Cell Counts

BackgroundAlthough Malignant Cutaneous Melanoma (CM) is a highly immunogenic cancer, it can evade the immune system by forming an immunosuppressive tumor microenvironment (TME). FoxP3+ Regulatory T cells (Tregs) and indoleamine-2,3-dioxygenase (IDO) are a part of the immunosuppressive TME in CM. In previous studies, IDO expression correlates with poor prognosis and greater Breslow’s depth, but results concerning the role of FoxP3+ Tregs in CM have been controversial. Furthermore, the correlation between IDO and Tregs has not been substantially studied in CM, although IDO is known to be an important regulator of Tregs activity. To develop new therapeutic strategies, it is important to understand the role of immunosuppressive factors in CM.Materials and MethodsWe investigated the associations of FoxP3+ Tregs, IDO+ tumor cells and IDO+ stromal immune cells with tumor stage, prognostic factors, and survival in CM. FoxP3 and IDO were immunohistochemically stained from 29 benign and 29 dysplastic nevi, 18 in situ -melanomas, 48 superficial and 62 deep melanomas and 67 lymph node metastases of CM. The number of FoxP3+ Tregs and IDO+ stromal immune cells was analysed quantitatively and the coverage and intensity of IDO+ tumor cells was evaluated semiquantitatively. Tumors were divided into IDO-negative and IDO-positive, containing less or more than 1% IDO+ melanoma cells of all tumor cells, respectively. P values equal to or less than 0.05 were considered statistically significant.ResultsIDO+ stromal immune cells and FoxP3+ Tregs mainly accumulated in the areas with lymphocyte infiltration and thus resided mostly in the perilesional stroma. The number of FoxP3+ Tregs and IDO+ stromal immune cells were significantly higher in malignant melanomas compared with benign lesions. The increased expression of IDO in melanoma cells was associated with poor prognostic factors, such as recurrence, nodular growth pattern and increased mitotic count. Furthermore, the expression of IDO in melanoma cells was associated with reduced recurrence-free survival. We further showed that IDO-positive tumors contained significantly higher amounts of FoxP3+ Tregs and IDO+ stromal immune cells than IDO-negative tumors. However, the correlation between FoxP3+ Treg and IDO+ stromal immune cell counts was rather weak.ConclusionsOur results indicate that IDO expression is intimately involved in creating a TME conducive to tumor growth in CM. Thus, targeting IDO enzymatic pathway might be a worth of further studies in CM. Furthermore, we show that FoxP3+ Tregs appear to contribute to the immunosuppressive TME in CM, but their role may not be that critical to melanoma progression. The positive association of FoxP3+ Tregs with IDO+ melanoma cells, but not with IDO+ stromal immune cells, indicates a complex interaction between IDO and Tregs in CM, which demands further studies. Support: Sigrid Juselius Foundation (S.P.-S.), Academy of Finland (S.P.-S.), The Paavo Koistinen Foundation (S.S.), Emil Aaltonen Foundation (S.S.) and North-Savo Cultural Foundation (S.S.).Disclosure InformationS. Salmi: None. A. Lin: None. B. Hirschovits-Gerz: None. M. Valkonen: None. N. Aaltonen: None. R. Sironen: None. H. Siiskonen: None. S. Pasonen-Seppänen: None.

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The Pivotal Role of Regulatory T Cells in the Regulation of Innate Immune Cells

Frontiers in Immunology ◽

10.3389/fimmu.2019.00680 ◽

2019 ◽

Vol 10 ◽

Cited By ~ 31

Author(s):

Emeka B. Okeke ◽

Jude E. Uzonna

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Immune Cells ◽

Innate Immune ◽

Pivotal Role ◽

Innate Immune Cells

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Tumor Immune Microenvironment and Its Related miRNAs in Tumor Progression

Frontiers in Immunology ◽

10.3389/fimmu.2021.624725 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yingying Xing ◽

Guojing Ruan ◽

Haiwei Ni ◽

Hai Qin ◽

Simiao Chen ◽

...

Keyword(s):

T Cells ◽

Tumor Progression ◽

Tumor Cells ◽

Immune Cells ◽

Suppressor Cells ◽

Immune Microenvironment ◽

Non Coding Rna ◽

Tumor Immune Microenvironment ◽

Downstream Gene Expression

MiRNA is a type of small non-coding RNA, by regulating downstream gene expression that affects the progression of multiple diseases, especially cancer. MiRNA can participate in the biological processes of tumor, including proliferation, invasion and escape, and exhibit tumor enhancement or inhibition. The tumor immune microenvironment contains numerous immune cells. These cells include lymphocytes with tumor suppressor effects such as CD8+ T cells and natural killer cells, as well as some tumor-promoting cells with immunosuppressive functions, such as regulatory T cells and myeloid-derived suppressor cells. MiRNA can affect the tumor immune microenvironment by regulating the function of immune cells, which in turn modulates the progression of tumor cells. Investigating the role of miRNA in regulating the tumor immune microenvironment will help elucidate the specific mechanisms of interaction between immune cells and tumor cells, and may facilitate the use of miRNA as a predictor of immune disorders in tumor progression. This review summarizes the multifarious roles of miRNA in tumor progression through regulation of the tumor immune microenvironment, and provides guidance for the development of miRNA drugs to treat tumors and for the use of miRNA as an auxiliary means in tumor immunotherapy.

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MicroRNAs expression profile in CCR6+ regulatory T cells

10.7287/peerj.preprints.471v2 ◽

2014 ◽

Author(s):

Juanjuan Zhao ◽

Yongju Li ◽

Yan Hu ◽

Chao Chen ◽

Ya Zhou ◽

...

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Signaling Pathways ◽

Expression Profile ◽

Immune Cells ◽

Potential Role ◽

Biological Function ◽

Fold Change ◽

Insight Into

Backgroud: CCR6+ CD4+ regulatory T cells (CCR6+Tregs), a distinct Tregs subset, played an important role in various immune diseases. Recent evidence showed that microRNAs (miRNAs) are vital regulators in the function of immune cells. However, the potential role of miRNAs in the function of CCR6+Tregs remains largely unknown. In this study, we detected the expression profile of miRNAs in CCR6+ Tregs. Materials and Methods: The expression profile of miRNAs as well as genes in CCR6+Tregs or CCR6-Tregs from Balb/c mice were detected by microarray. The signaling pathways were analyzed using Keggs pathway library. Results: We found that there were 58 miRNAs significantly upregulated and 62 downregulated up to 2 fold in CCR6+Tregs compared with CCR6-Tregs. Moreover, 1391 genes were observed with 3 fold change and 20 signaling pathways were enriched using Keggs pathway library. Conclusion: The present data firstly showed CCR6+Tregs expressed specific miRNAs pattern, which provide an insight into the role of miRNAs in the biological function of distinct Tregs subsets.

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MicroRNAs expression profile in CCR6+ regulatory T cells

10.7287/peerj.preprints.471 ◽

2014 ◽

Author(s):

Juanjuan Zhao ◽

Yongju Li ◽

Yan Hu ◽

Chao Chen ◽

Ya Zhou ◽

...

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Signaling Pathways ◽

Expression Profile ◽

Immune Cells ◽

Potential Role ◽

Biological Function ◽

Fold Change ◽

Insight Into

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Common Peripheral Immunity Mechanisms in Multiple Sclerosis and Alzheimer's Disease

Frontiers in Immunology ◽

10.3389/fimmu.2021.639369 ◽

2021 ◽

Vol 12 ◽

Author(s):

Barbara Rossi ◽

Bruno Santos-Lima ◽

Eleonora Terrabuio ◽

Elena Zenaro ◽

Gabriela Constantin

Keyword(s):

Multiple Sclerosis ◽

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

T Cells ◽

Regulatory T Cells ◽

Neurodegenerative Diseases ◽

Adaptive Immunity ◽

Immune Cells ◽

Pharmacological Intervention

Neurodegenerative diseases are closely related to inflammatory and autoimmune events, suggesting that the dysregulation of the immune system is a key pathological factor. Both multiple sclerosis (MS) and Alzheimer's disease (AD) are characterized by infiltrating immune cells, activated microglia, astrocyte proliferation, and neuronal damage. Moreover, MS and AD share a common pro-inflammatory signature, characterized by peripheral leukocyte activation and transmigration to the central nervous system (CNS). MS and AD are both characterized by the accumulation of activated neutrophils in the blood, leading to progressive impairment of the blood–brain barrier. Having migrated to the CNS during the early phases of MS and AD, neutrophils promote local inflammation that contributes to pathogenesis and clinical progression. The role of circulating T cells in MS is well-established, whereas the contribution of adaptive immunity to AD pathogenesis and progression is a more recent discovery. Even so, blocking the transmigration of T cells to the CNS can benefit both MS and AD patients, suggesting that common adaptive immunity mechanisms play a detrimental role in each disease. There is also growing evidence that regulatory T cells are beneficial during the initial stages of MS and AD, supporting the link between the modulatory immune compartments and these neurodegenerative disorders. The number of resting regulatory T cells declines in both diseases, indicating a common pathogenic mechanism involving the dysregulation of these cells, although their precise role in the control of neuroinflammation remains unclear. The modulation of leukocyte functions can benefit MS patients, so more insight into the role of peripheral immune cells may reveal new targets for pharmacological intervention in other neuroinflammatory and neurodegenerative diseases, including AD.

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Activation of Murine Immune Cells upon Co-culture with Plasma-treated B16F10 Melanoma Cells

Applied Sciences ◽

10.3390/app9040660 ◽

2019 ◽

Vol 9 (4) ◽

pp. 660 ◽

Cited By ~ 17

Author(s):

Katrin Rödder ◽

Juliane Moritz ◽

Vandana Miller ◽

Klaus-Dieter Weltmann ◽

Hans-Robert Metelmann ◽

...

Keyword(s):

Tumor Cells ◽

Immune Cells ◽

Melanoma Cells ◽

B16f10 Melanoma ◽

Migratory Activity ◽

Erk Phosphorylation ◽

Extracellular Signal ◽

B16f10 Melanoma Cells ◽

Physical Plasma

Recent advances in melanoma therapy increased median survival in patients. However, death rates are still high, motivating the need of novel avenues in melanoma treatment. Cold physical plasma expels a cocktail of reactive species that have been suggested for cancer treatment. High species concentrations can be used to exploit apoptotic redox signaling pathways in tumor cells. Moreover, an immune-stimulatory role of plasma treatment, as well as plasma-killed tumor cells, was recently proposed, but studies using primary immune cells are scarce. To this end, we investigated the role of plasma-treated murine B16F10 melanoma cells in modulating murine immune cells’ activation and marker profile. Melanoma cells exposed to plasma showed reduced metabolic and migratory activity, and an increased release of danger signals (ATP, CXCL1). This led to an altered cytokine profile with interleukin-1β (IL-1β) and CCL4 being significantly increased in plasma-treated mono- and co-cultures with immune cells. In T cells, plasma-treated melanoma cells induced extracellular signal-regulated Kinase (ERK) phosphorylation and increased CD28 expression, suggesting their activation. In monocytes, CD115 expression was elevated as a marker for activation. In summary, here we provide proof of concept that plasma-killed tumor cells are recognized immunologically, and that plasma exerts stimulating effects on immune cells alone.

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Knockout of High-Mobility Group Box 1 in B16F10 Melanoma Cells Induced Host Immunity-Mediated Suppression of In Vivo Tumor Growth

10.21203/rs.3.rs-1187786/v1 ◽

2021 ◽

Author(s):

Kanako Yokomizo ◽

Kayoko Waki ◽

Miyako Ozawa ◽

Keiko Yamamoto ◽

Sachiko Ogasawara ◽

...

Keyword(s):

T Cells ◽

Tumor Microenvironment ◽

Tumor Growth ◽

Tumor Cells ◽

Tumor Immunity ◽

Cd8 T Cells ◽

Immune Cells ◽

High Mobility

Abstract High mobility group box 1 (HMGB1) has been reported as a damage-associated molecular pattern (DAMP) molecule that is released from damaged or dead cells and induces inflammation and subsequent innate immunity. However, the role of HMGB1 in the anti-tumor immunity is unclear since inflammation in the tumor microenvironment also contributes to tumor promotion and progression. In the present study, we established HMGB1-knockout clones from B16F10 and CT26 murine tumors by genome editing using the CRISPR/Cas9 system and investigated the role of HMGB1 in anti-tumor immunity. We found that 1) knockout of HMGB1 in the tumor cells suppressed in vivo, but not in vitro, tumor growth, 2) the suppression of the in vivo tumor growth was mediated by CD8 T cells, and 3) infiltration of CD8 T cells, macrophages and dendritic cells into the tumor tissues was accelerated in HMGB1-knockout tumors. These results demonstrated that knockout of HMGB1 in tumor cells converted tumors from poor infiltration of immune cells called “cold” to “immune-inflamed” or “hot” and inhibited in vivo tumor growth mediated by cytotoxic T lymphocytes. Infiltration of immune cells to the tumor microenvironment is an important step in the series known as the cancer immunity cycle. Thus, manipulation of tumor-derived HMGB1 might be applicable to improve the clinical outcomes of cancer immunotherapies, including immune checkpoint blockades and cancer vaccine therapies.

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Role of CCL21 on the Transcriptional Regulation of MHC II in Malignant Glioma Infiltrating Plasmacytoid Dendritic Cells

Proceedings of IMPRS ◽

10.18060/22737 ◽

2018 ◽

Vol 1 (1) ◽

Author(s):

Sharlé Newman ◽

Sreenivasulu Chintala ◽

Mario Henriquez ◽

Mahua Dey

Keyword(s):

T Cells ◽

Dendritic Cells ◽

Tumor Cells ◽

Immune Cells ◽

Plasmacytoid Dendritic Cells ◽

Potential Therapeutic Target ◽

Mhc Ii ◽

Immunosuppressive Tumor Microenvironment ◽

Potential Impact

Background and Hypothesis: Glioblastoma (GBM) is a malignant brain tumor characterized by high tumor heterogeneity and an immunosuppressive tumor microenvironment (TME). Immunomodulation approaches have been investigated, but outcomes remain poor. Several studies describe the functional deregulation of immune cells including, T cells, dendritic cells (DC), and macrophages. Plasmacytoid dendritic cells (pDC), which accumulate in the GBM TME, are shown to have an immunosuppressive phenotype characterized by a lack of IFN-[Symbol] secretion and upregulation of MHC II. MHC II presentation is transcriptionally regulated by several factors produced by tumor cells including, TGFβ, TNFα, and IL10 through the modulation of CIITA, the catalytic component of the enhanceosome. GBM tumor cells secrete several chemokines/cytokines, which may regulate MHC II expression in pDCs. We hypothesize that chemokine CCL21 transcriptionally upregulates MHC II through the activation of CIITA in pDC. Experimental Design/Project methods: We performed experiments using two GBM tumor cells models GL261 and CT2A and used western blot, PCR, immunohistochemistry, immunofluorescence, and flow cytometry to determine the levels of CCL21 and its ligands ACKR3/4 in tumor cells and pDC. Results: We observed overexpression of CCL21 in GBM and upregulation of MHCII in tumor associated pDC. We predict that inhibition of CCL21 will lead to downregulation of MHC II in tumor associated pDC which could potentially lead to reversal of the immunosuppressive TME by presenting the antigens to T cells. Conclusions/Potential Impact: The results of this study can elucidate novel mechanisms of MHCII regulation and identify CCL21 as a potential therapeutic target for immunotherapy development in GBM.

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