Congenital localized cutaneous Langerhans cell histiocytosis in a Holstein calf.

Distinct solitary dermal nodules, either covered by an alopecic, or sometimes ulcerated, epidermis, were noticed on the head of a stillborn Holstein calf. The head was submitted for autopsy, and the nodules were found to consist of homogeneous, diffuse pale-yellow, soft-tissue masses with distinct margins that elevated the epidermis above the adjacent skin. Histologically, the dermal nodules were well-delineated on the deep margin approaching the cutaneous muscle and consisted of perivascular neoplastic infiltrates of round cells that in some places coalesced into sheets that extended into the dermis and subcutis. Neoplastic cells separated adnexa and collagen. Immunohistochemistry revealed intense tumor cell expression of vimentin, Iba1, E-cadherin, and CD204; expression of CD18 was faint. The masses were diagnosed as Langerhans cell histiocytosis. Congenital cutaneous Langerhans cell histiocytosis has not been reported previously in cattle, to our knowledge, and should be included in the differential diagnosis of congenital nodular skin lesions.

Profiling Fibroblast Growth Factor Receptor 3 Expression Based on the Immune Microenvironment in Upper Tract Urothelial Carcinoma.

BACKGROUND: Although several studies have shown favorable outcomes in upper tract urothelial carcinoma (UTUC) with fibroblast growth factor receptor 3 (FGFR3) mutations and/or expression, the relationship between immune cell markers and FGFR3 expression remains unknown. OBJECTIVE: To clarify the FGFR3-based immune microenvironment and investigate biomarkers to predict the treatment response to pembrolizumab (Pem) in patients with UTUC. DESIGN, SETTING, AND PARTICIPANTS: We conducted immunohistochemical staining in 214 patients with UTUC. The expression levels of FGFR3, CD4, CD8, CD68, CD163, CD204, and programmed cell death ligand 1 (PD-L1) were examined. INTERVENTION: All UTUC patients underwent radical nephroureterectomy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We assessed the relationship between these immune markers and patient prognosis. RESULTS AND LIMITATIONS: A total of 109 (50.9%) patients showed high FGFR3 expressions and a favorable prognosis compared with the remaining patients. Among the six immune markers, CD8 high expression was an independent favorable factor, whereas CD204 expression was an independent prognostic factor for cancer death. From the FGFR3-based immune clustering, three immune clusters were identified. Cluster A showed low FGFR3 with tumor-associated macrophage-rich components (CD204+) followed by a poor prognosis due to a poor response to Pem. Cluster B showed low FGFR3 with an immune hot component (CD8+), followed by the most favorable prognosis owing to a good response to Pem. Cluster C showed high FGFR3 expression but an immune cold component, followed by a favorable prognosis due to the high FGFR3 expression, but a poor response was confirmed with Pem. CONCLUSIONS: Although most patients exhibit a poor response to Pem, individuals with low FGFR3 expression and immune hot status may benefit clinically from Pem treatment. PATIENT SUMMARY: We conducted immunohistochemical staining to evaluate fibroblast growth factor receptor 3 (FGFR3)-related immune microenvironment by evaluating the expressions of CD4, CD8, CD68, CD163, CD204, and PD-L1 in 214 upper tract urothelial carcinoma patients. We identified three distinct immune clusters based on FGFR3 expressions and found that patients with a low FGFR3 expression but immune hot status received the maximum benefit from an immune checkpoint inhibitor.

High CD204+ tumor-associated macrophage density predicts a poor prognosis in patients with clear cell renal cell carcinoma.

Purpose: Tumor-associated macrophages (TAMs) play a crucial role in solid tumors and display varying characteristics depending on the specific tumor microenvironment (TME). The study investigated the presence and characteristics of TAMs in renal clear cell carcinoma (ccRCC) and assessed their influence on patient prognosis. Methods: Immunohistochemistry (IHC) was used to identify CD204+ TAMs in a cohort of 72 patients with ccRCC. Kaplan-Meier survival analysis and log-rank test were used to evaluate the prognostic significance of CD204+ TAMs in each group. The TCGA-KIRC cohort was used to analyze the relationship between CD204 and immunity. The functions of CD204+ TAMs in the TCGA-KIRC cohort were analyzed through GO enrichment analysis. Immunofluorescence (IF) was conducted to confirm the positive effects of CD204 on regulatory T (Treg) cells and exhausted T (Tex) cells. Results: There was a negative relation between high infiltration of CD204+ TAMs and both overall survival (OS) and progression-free survival (PFS) in ccRCC. A positive correlation was found between high-infiltrating CD204+ TAMs and distant organ metastasis, as well as lymph node metastasis. In the TCGA-KIRC cohort, the group with high expression of CD204 exhibited significant up-regulation of 120 genes as well as enrichment in the negative regulation of immunity. CD204 high-expression group showed up-regulation of Treg cells and Tex cells. Conclusion: The presence of CD204+ TAMs in ccRCC is associated with a negative prognosis in patients. The high infiltration of CD204 promotes distant organ metastasis by aggerating Treg cells and Tex cells.

Hemosiderin-Laden Macrophages in Canine Mammary Carcinomas.

Macrophages are among the main actors in cancer immunoediting, with several functions, including recycling iron and packaging it in hemosiderin. Even though TAMs are widely studied in breast cancer and canine mammary tumors, hemosiderin-laden macrophages (HLMs) have not received as much attention. Considering the growing interest in iron metabolism in cancer, this study aims to evaluate the presence of HLMs in canine mammary tumors. Fifty cases of canine mammary carcinomas presenting aggregates of pigmented macrophages were chosen. Prussian blue and Meguro staining were performed to assess the presence of iron. Immunohistochemistry was carried out to try to identify macrophagic phenotypes and hypothesize their role. Evaluation of the H&E sections showed that pigmented macrophages were variously localized in peritumoral and stromal areas. These pigmented cells were variably stained with Prussian blue and reacted strongly with DAB in the Meguro staining method, thus confirming the presence of iron within them. In their immunohistochemistry, the HLMs were negative for the MAC387 but positive for CD 204 and VEGF. Considering their positivity for CD 204, HLMs could be M2 macrophages that supply iron to both the neoplastic cells and the tumor inflammatory microenvironment, promoting angiogenesis and protecting cancer cells from hypoxia.

CD204⁺ tumor-associated macrophages are associated with clinical outcome in canine pulmonary adenocarcinoma and transitional cell carcinoma.

Tumor-associated macrophages are abundant infiltrating cells in the tumor microenvironment (TME). Macrophages can be classified into several types of subsets based on their immune responses. Among those subsets, M2 macrophages contribute to anti-inflammatory responses and create an immunosuppressive environment that promotes tumor cell proliferation. In a previous study, human cancer patients with high M2 macrophages showed a worse prognosis for many types of tumors. However, studies examining the relationship between M2 macrophages and clinical outcomes in canine tumors are limited. In the previous human and canine studies, CD204 has been used as the marker for detecting M2 macrophages. Then we evaluated CD204+ and total macrophages infiltration and its association with clinical outcomes in canine solid tumors. In this study, we examined dogs with oral malignant melanoma (OMM), pulmonary adenocarcinoma (PA), hepatocellular carcinoma (HCC), and transitional cell carcinoma (TCC). Compared to healthy tissues, CD204+ and total macrophages were increased in OMM, PA, and TCC, but not in HCC. High CD204+ macrophage levels were significantly associated with lung metastasis in TCC (P = 0.030). Kaplan-Meier analysis revealed that high CD204+ macrophage levels were associated with shorter overall survival (OS) in canine patients with PA (P = 0.012) and TCC (P = 0.0053). These results suggest that CD204+ macrophages contribute to tumor progression and could be a prognostic factor in dogs with PA and TCC.

Live Imaging of Monocyte/Macrophage Differentiation with Cationized Gelatin Nanospheres Incorporating a Molecular Beacon.

As one imaging method to evaluate monocyte-macrophage differentiation, cationized gelatin nanospheres incorporating a molecular beacon (MB) (cGNSMB) were designed. Cationized gelatin nanospheres (cGNS) of different apparent sizes were prepared by the conventional coacervation method, and then the MB of CD204 was incorporated into cGNS to prepare cGNSMB. When three types of cGNSMB were cultured with human monocytoma (THP-1) cells, the cGNSMB with a 110 nm diameter showed the highest MB delivery efficiency. In addition, no influence on the monocyte-macrophage differentiation was observed in terms of CD204 gene expression and cell viability. After incubation with cGNS incorporating CD204 MB (cGNSCD204), THP-1 cells were stimulated by phorbol 12-myristate 13-acetate (PMA) for monocyte differentiation into macrophages. The fluorescence intensity of macrophages increased with the incubation time. In contrast, the fluorescence intensity of macrophages incubated with MB alone was not changed. On the other hand, there was no change in the fluorescence intensity of original THP-1 cells cultured with cGNSCD204. It is concluded that the cGNSCD204 are promising to trace the differentiation of THP-1 cells into macrophages in their live condition.

The Cancer Driver Genes IDH1 and IDH2 and CD204 in WHO-Grade 4 Astrocytoma: Crosstalk Between Cancer Metabolism and Tumour Associated Macrophage Recruitment in Tumour Microenvironment.

Purpose: IDH1 and IDH2 are hotspot mutations commonly identified in WHO-grade 4 astrocytomas. Their association with TAMs has never been investigated. We aim to explore the crosstalk between the IDH1/2 mutation metabolic effect and TAMs in tumour microenvironment and how this relationship affects the tumour recurrence. Patients and Methods: The study included 20 samples of patients with WHO-grade 4 astrocytoma. The alteration hotspot in codon IDH1R132 and IDH2R172 was examined using direct sequencing. The protein expression of CD204 on TAM was detected through immunohistochemistry. Results: IDH1R132 and IDH2R172 were symmetrically identified as wildtype in 18/20 tumours (90%) and the remaining 2 tumours (10%) showed synonymous mutations on both codons. Tumours with IDH1/2-wildtype showed high expression of CD204+TAMs in 10 cases and low expression in 8 cases. Typical expression was seen equally in IDH1/2 mutant tumours. There was no significant association between IDH1/2 and CD204+TAM expression (p= 0.999). The association between the two groups was significantly observed among IDH-wildtype tumours (p=0.027). Highly expressed CD204 in IDH-wildtype tumours showed a median recurrence at 10 months compared to low CD204 expression, showed a median recurrence interval at 24 months. Conclusion: IDH1R132 or IDHR172 has the same impact on the classification and prognosis of WHO-grade 4 astrocytoma. There was no crosstalk between IDH1/2 metabolic effect and CD204+TAM. However, IDH-wildtype glioblastomas with dense CD204+TAM are associated with early recurrence. Because the sample size is small, a larger study is recommended to determine the impact of IDH1/2 on TAMs.

Involvement of protumor macrophages in breast cancer progression and characterization of macrophage phenotypes.

Tumor-associated macrophages (TAMs) are the most prominent immune cells in the breast cancer microenvironment, and the protumor functions of TAMs are thought to affect cancer progression and resistance to anticancer therapy. Numerous studies using human breast cancer samples, cell lines, and murine breast cancer models have revealed details of the mechanisms by which the protumor functions of TAMs are activated. Recent advances have highlighted the significant involvement of TAMs in the resistance of breast cancer cells to immunotherapy. Tumor-associated macrophages express a number of immunosuppressive genes, and single-cell sequence analyses of human and murine cancer samples have helped elucidate the mechanism of TAM-induced immunosuppression. As TAMs are considered suitable targets for anticancer therapies, we summarized the protumor functions of TAMs and the potential of anticancer therapies targeting TAMs, with a focus on breast cancer research.

Lipopolysaccharide-binding protein as a biomarker in oral and maxillofacial tumors.

Oral and maxillofacial tumors (OMTs), such as oral squamous cell carcinoma (SCC), pleomorphic adenoma, and ameloblastoma, are common head and neck tumors. Lipopolysaccharide-binding protein (LBP) is a type I acute reactive protein, which participates in body inflammatory response modulation through lipopolysaccharide (LPS)-induced signaling pathway by targeting macrophages (expressing cluster of differentiation 204 [CD204]). Although it is well established that LBP is associated with the development of multiple types of cancer, little is known about the role of LBP in OMTs. This study aims to explore the expression of LBP in OMTs. Here, immunohistochemical (IHC) double staining of LBP and CD204 and enzyme-linked immunosorbent assay (ELISA) were conducted to explore the LBP expression in OMTs. The findings demonstrated that the LBP expression in OMTs was significantly elevated (p < 0.001). In addition, the LBP expression was associated with the clinical stage (p < 0.001), T classification (p < 0.001), and lymph node metastasis (p < 0.001, except ELISA) but independent of histological grade of SCC, gender, and age in patients with SCC. The optional cutoff of the LBP serum level is 0.721 µg/ml. To conclude, LBP contributes to the development of OMTs and could be a biomarker in the screening and predicting metastasis in patients with OMTs.

The prognostic role of tumor associated macrophages in squamous cell carcinoma of the head and neck: A systematic review and meta-analysis.

Head and neck squamous cell carcinoma (HNSCC) is an immunogenic cancer type, and tumor associated macrophages (TAMs) are a major component of the tumor microenvironment (TME). In this systematic review and meta-analysis, studies assessing tumor infiltration with CD68+, iNOS+, HLA-DR+, CD11b+, CD163+, CD206+, and CD204+TAMs were included, and correlation to survival hazard was studied. A low number of CD68+TAMs correlated to better overall survival (OS) in multivariate analysis (HR 1.36 95 %CI (1.07-1.72) P = .01). CD68+TAMs did not correlate to disease free survival (DFS), disease specific survival (DSS), progression free survival (PFS), or recurrence free survival (RFS). A low number of CD163+TAMs correlated to better OS in uni- and multivariate analysis (resp. HR 2.65 95 %CI (1.57-4.46) P = .01 and HR 2.42 95 %CI (1.72-3.41) P < .001). A low number of CD163+TAMs also correlated to better DFS and PFS, whereas a low number of CD204+TAMs only correlated to PFS. While IHC analysis of pan macrophage marker CD68 and M2-like marker CD163 both show prognostic utility in OS, CD163 is a stronger prognosticator, as indicated by multivariate meta-analysis. CD163+TAMs also correlate to DFS and PFS; outcomes that are more relevant to patients, thus showing promising results for future clinical implementation.

The role of macrophage scavenger receptor 1 (MSR1) in inflammatory disorders and cancer.

Macrophage scavenger receptor 1 (MSR1), also named CD204, holds key inflammatory roles in multiple pathophysiologic processes. Present primarily on the surface of various types of macrophage, this receptor variably affects processes such as atherosclerosis, innate and adaptive immunity, lung and liver disease, and more recently, cancer. As highlighted throughout this review, the role of MSR1 is often dichotomous, being either host protective or detrimental to the pathogenesis of disease. We will discuss the role of MSR1 in health and disease with a focus on the molecular mechanisms influencing MSR1 expression, how altered expression affects disease process and macrophage function, the limited cell signalling pathways discovered thus far, the emerging role of MSR1 in tumour associated macrophages as well as the therapeutic potential of targeting MSR1.

Tumor-Associated Macrophages in Canine Oral and Cutaneous Melanomas and Melanocytomas: Phenotypic and Prognostic Assessment.

The tumor microenvironment is a complex system, where neoplastic cells interact with immune and stromal cells. Tumor-associated macrophages (TAMs) are considered among the most numerically and biologically noteworthy cellular components in tumors and the attention on this cellular population has been growing during the last decade, both for its prognostic role and as a potential future therapeutic target. Melanoma, particularly the oral form, despite being one of the most immunogenic tumors, bears a poor prognosis in dogs and humans, due to its highly aggressive biological behavior and limited therapeutic options. The aims of this study are to characterize and quantify TAMs (using CD163, CD204, Iba1, and MAC387) in canine melanocytic tumors and to evaluate the association of these markers with diagnosis, histologic prognostic features, presence of metastases, and outcome, and to provide preliminary data for possible future therapies targeting TAMs. Seventy-two melanocytic tumors (27 oral melanomas, 25 cutaneous melanomas, 14 cutaneous melanocytomas, and 6 oral melanocytomas) were retrospectively selected and submitted to immunohistochemistry and double immunofluorescence. Double immunolabeling revealed that most CD163+ and CD204+cells co-expressed Iba1, which labeled also dendritic cells. Iba1 was instead rarely co-expressed with MAC387. Nevertheless, the expression of macrophagic markers showed a mild to moderate association among the four markers, except for CD204 and MAC387. The number of CD163+, CD204+, and MAC387+ cells was significantly higher in oral melanomas compared to oral melanocytomas (p < 0.001; p < 0.05 and p < 0.01, respectively), whereas Iba1 was differentially expressed in cutaneous melanomas and melanocytomas (p < 0.05). Moreover, CD163, IBA1 and MAC387 expression was associated with nuclear atypia and mitotic count. The number of CD163+cells was associated with the presence of metastases and tumor-related death in oral melanocytic tumors (p < 0.05 and p = 0.001, respectively).

Association Between CD204-Expressed Tumor-Associated Macrophages and MGMT-Promoter Methylation in the Microenvironment of Grade 4 Astrocytomas.

Background: Tumor-associated macrophages (TAMs) are principal immune cells in glioma microenvironment which support tumor growth and proliferation. Our aim in this study was to assess the relationship between CD204-expressed TAMs and O6-methylguanine-DNA methyltransferase (MGMT)-promoter methylation in World Health Organization (WHO) grade 4 astrocytomas, and its impact on patient's clinical outcome. Methods: The expression of CD204 + TAMs was quantitively assessed on 45 samples of WHO grade 4 astrocytomas using immunohistochemistry. MGMT-promoter methylation was tested by methylation techniques. The relationship between TAMs, MGMT-promoter methylation, and recurrence-free interval (RFI) was statistically analyzed. Results: There were 10 cases (22.2%) with isocitrate dehydrogenase (IDH)-mutant grade 4 astrocytoma and 35 cases (77.8%) with IDH-wildtype glioblastoma. MGMT-promotor was methylated in 18 cases (40%), unmethylated in 15 cases (33%), and the remaining 12 cases showed no MGMT status because of nucleic acid degradations. The expression of CD204+ TAMs was high in 32 cases (71.7%) and low in 13 cases (28.8%). The relationship between IDH1 mutation and CD204+ TAM expression was insignificant (P = 0.93). However, the significant difference was found between MGMT methylation and CD204+ TAMs expression (P = 0.01), in which CD204+ TAMs were diffusely expressed in MGMT-methylated cases. There was no significant difference in RFI between CD204+ TAMs expression, MGMT-promoter methylation and treatment modalities. Conclusions: Grade 4 astrocytomas with diffusely expressed CD204+ TAMs are usually associated with MGMT-promoter methylation. Although this association is unclear, CD204+ TAMs may neutralize the effect of MGMT-DNA protein to loss its function, which contributes to tumor progression. This relationship had no significant impact on the patient's clinical outcome after different treatment modalities.

The CD36 and SR-A/CD204 scavenger receptors fine-tune Staphylococcus aureus-stimulated cytokine production in mouse macrophages.

The occurring in SR-A/CD204- or CD36-deficient mice increased susceptibility to infections with Staphylococcus aureus (Sa) had traditionally been ascribed to the impairment of macrophage-mediated phagocytosis, which is, however, inconsistent with low effectiveness of unopsonized Sa killing within macrophages and redundant roles of both receptors in this process. We have found that Sa-stimulated cytokine production in mouse macrophages seems to be exclusively mediated by TLR2, mainly from within endosomes in response to Sa-derived lipoteichoic acid. By driving endocytic trafficking of TLR2 and its ligands through the clathrin-dependent pathway, CD36 and SR-A sensitize macrophages to activation by Sa as well as regulate the type and amount of cytokines produced. Additionally, upon direct Sa binding, both receptors autonomously generate anti-inflammatory signaling. Consequently, the delayed induction of acute inflammation in knockout mice may allow for the initial, uncontrolled multiplication of bacteria, stimulating excessive, septic shock-inducing production of inflammatory cytokines in later stages of infection.

Tumour-associated CD204+ microglia/macrophages accumulate in perivascular and perinecrotic niches and correlate with an interleukin-6-enriched inflammatory profile in glioblastoma.

AIMS: Glioblastomas are heterogeneous tumours with a rich tumour microenvironment particularly comprised of tumour-associated microglia/macrophages (TAMs), but also containing a population of dedifferentiated/stem-like glioblastoma cells. Both cell populations contribute to tumour aggressiveness and immune evasion through the actions of various signalling molecules. The scavenger and pattern recognition receptor CD204 is associated with a pro-tumourigenic phenotype of TAMs and has a negative prognostic value. Our objective was to investigate the possible interaction between TAMs and dedifferentiated glioblastoma cells and characterise the myeloid phenotype of CD204-enriched glioblastomas. METHODS: Double immunohistochemistry and cell counting was performed on eight glioblastoma samples to estimate the expression and interaction level between dedifferentiated/stem-like tumour cells and TAMs. Using the NanoString technology, myeloid transcriptome profiling was performed on 46 glioblastomas, which had been selected based on their protein expression levels of CD204 and ionised calcium-binding adaptor molecule-1 (IBA1). The results were validated by immunohistochemistry and in silico gene expression analyses. RESULTS: TAMs especially CD204+ TAMs accumulated in perivascular and perinecrotic niches in close proximity to podoplanin+ glioblastoma cells. Gene profiling revealed that CD204-enriched glioblastoma has a unique signature with upregulation of genes related to hypoxia, angiogenesis and invasion, including interleukin-6. The gene signature favoured a poor prognosis in patients with glioblastoma. CONCLUSIONS: This is the first study to characterise the role of CD204 in the myeloid microenvironment of glioblastoma. Our results support the unfavourable prognostic impact of CD204 and suggest that CD204 and interleukin-6 could serve as targets for re-education of TAMs and potentiation of current anti-glioma therapy.

Infiltration of CD204-overexpressing Macrophages Contributes to the Progression of Stage II and III Colorectal Cancer.

BACKGROUND/AIM: M1 macrophages have antitumour effects, while M2 macrophages promote tumour proliferation and invasion. The clinical significance of the M2-specific marker CD204 has not been elucidated in colorectal cancer (CRC). We investigated the prognostic significance of CD204- and CD68-positivity in specimens from patients with CRC and examined the effects of M2 polarized-macrophages on the proliferative and invasive potentials of CRC cell lines in vitro. MATERIALS AND METHODS: Surgical tumour specimens from 206 patients with Stage II and III CRC were examined by immunohistochemistry. Proliferation and invasion assays and flow cytometry were used to investigate CD204 expression in macrophages co-cultured with three CRC cell lines. RESULTS: Infiltration of CD204-positive cells was significantly associated with shorter overall survival and relapse-free survival; no association was observed for CD68. M2-polarized macrophages significantly promoted proliferation and invasion of CRC cells. CONCLUSION: Higher infiltration of CD204-positive macrophages into the tumour-microenvironment might be prognostically important in CRC.

M1 and M2 tumour-associated macrophages subsets in canine malignant mammary tumours: An immunohistochemical study.

Among the innate and adaptative immune cells recruited to the tumour site, tumour associated macrophages (TAMs) are particularly abundant and by simplified classification can be classified into (M1) and (M2) TAMs. In the present study, we quantified by immunohistochemistry ionized calcium binding adaptor molecule 1 (Iba1)-positive total and CD204-positive M2-polarized TAMs in 60 canine malignant mammary tumours (CMMTs) to analyze the relationship between M1 or M2 response and the histopathologic features of examined CMMTs, the dogs' body condition score (BCS) and the progression of the neoplastic disease. The mean number of total and CD204+ TAMS were significantly higher in solid and in grade III than in grades I and II carcinomas. Moreover, the mean number of CD204-positive TAMs was significantly higher in CMMTs with lymphatic invasion and necrosis rather than CMMTs without. The presence of higher number of CD204-positive M2-polarized TAMs was associated with a worst outcome of the neoplastic disease: bitches bearing CMMTs with a prevalent M2-polarized TAM response had a median cancer-specific survival time of 449 days, while in animals with a M1-polarized TAM response the median cancer-specific survival time was 1209 days. The results of our study confirm that in CMMTs the presence of a M2-polarized TAMs response might affect the tumour development and behaviour. Finally, it strongly suggests the potential of CD204 expression as a prognostic factor.

The relationship between CD204 M2-polarized tumour-associated macrophages (TAMs), tumour-infiltrating lymphocytes (TILs), and microglial activation in glioblastoma microenvironment: a novel immune checkpoint receptor target.

BACKGROUND: Tumour associated macrophages (TAMs) and tumour infiltrating lymphocytes (TILs) are considered dominant cells in glioblastoma microenvironment. AIM: The purpose of this study was to assess the expression of CD204+ M2-polarized TAMs in glioblastomas and their relationship with CD4+TILs, Iba+microglia, and IDH1 mutation. We also exploreed the prognostic value of these markers on the recurrence-free interval (RFI). METHODS: The expressions of CD204+TAMs, CD4+TILs, and Iba1+microglia were quantitively assessed in 45 glioblastomas using immunohistochemistry. Kaplan-Meier analysis and Cox hazards were used to examine the relationship between these factors. RESULTS: CD204+TAMs were highly expressed in 32 tumours (71%) and the remaining 13 tumours (29%) had reduced expression. CD4+TILs were highly expressed in 10 cases (22%) and 35 cases (77.8%) had low expression. There was an inverse correlation between CD204+TAMs and CD4+TILs, in which 85% of tumours had a high expression of CD204+TAMs and a low expression of CD4+TILs. Nevertheless, there was no significant difference in IDH1 mutation status between the two groups (p = 0.779). There was a significant difference in Iba1+microglial activation between IDH1mutant and IDH1wildtype groups (p = 0.031). For cases with a high expression of CD204+TAMs and a low expression of CD4+TILs, there was a significant difference in RFI after treatment with chemoradiotherapy or radiotherapy (p = 0.030). CONCLUSION: Glioblastoma with a dense CD204+TAMs and few CD4+TILs is associated with IDH1wildtype. These findings suggest that TAMs masks tumour cell and suppress T-cell tumoricidal functions via immunomodulatory mechanisms. Blockade of the CD204-TAM receptor may prevent this mechanism and allow the evolution of TILs.

CD204-positive macrophages accumulate in breast cancer tumors with high levels of infiltrating lymphocytes and programmed death ligand-1 expression.

Although immunotherapy has been demonstrated to be promising in triple-negative (TN) breast cancer (BC), most BC cases are classified as non-TN. To enrich the responders for immunotherapy regardless of their subtypes, classification based on tumor-infiltrating lymphocyte (TIL) levels and programmed death ligand-1 (PD-L1) status may be useful. However, this classification has not been fully applied to BC. Furthermore, suppressive subsets in the local tumor microenvironment, such as tumor-associated macrophages (TAMs), which promote tumor progression, cannot be ignored to overcome immunotherapy resistance. The aims of the present study were to classify primary BC cases based on the TIL levels and PD-L1 status, and to identify suppressive immune subsets in each categorized group. A retrospective analysis of 73 patients with invasive BC was performed. The frequency of TILs was evaluated in HE-stained slides (10% cutoff), and PD-L1 levels (SP142; 1% cutoff), as well as immune subsets (CD3+, CD8+, FOXP3+, CD20+, CD68+ and CD204+ cells) were assessed using immunohistochemistry. It was revealed that 22% (16/73) of the tumors were categorized as TIL+PD-L1+, of which 69% (11/16) were TN type. By contrast, 66% (48/73) of the tumors were categorized as TIL-PD-L1-, of which 77% (37/48) were HR+ and HER2- types. The number of CD204+ M2-type macrophages was significantly associated with high histological grade (P=0.0246) and high Ki-67 (P=0.0152), whereas CD68+ macrophages were not associated with these factors. Furthermore, CD204+ macrophages and FOXP3+ Tregs accumulated in 88% (14/16) and 63% (10/16) of TIL+PD-L1+ tumors, respectively, compared with 20.8% (10/48) and 27.1% (13/48) of TIL-PD-L1- tumors. In conclusion, 22% of BC tumors were classified as TIL+PD-L1+ (69% were TN), which were enriched with suppressive immune subsets. These cell types may serve as potential novel immunotherapeutic targets.

Immunophenotyping of Nonneoplastic and Neoplastic Histiocytes in Cats and Characterization of a Novel Cell Line Derived From Feline Progressive Histiocytosis.

Histiocytic proliferative diseases are rare in cats, and their pathogenesis is poorly understood. In the present study, 25 cases of histiocytic sarcoma (HS) and 6 of feline progressive histiocytosis (FPH) were examined, and survival times were recorded in 19 cases. The immunophenotypes of tumor cells in these cases as well as of nonneoplastic feline histiocytes were characterized using formalin-fixed, paraffin-embedded tissues. An FPH cell line (AS-FPH01) and xenotransplant mouse model of FPH were also established. The median survival time of HS (150 days) was significantly shorter than that of FPH (470 days). Immunohistochemically, nonneoplastic histiocytes were immunopositive for various combinations of Iba-1, HLA-DR, E-cadherin, CD204, CD163, CD208, and MAC387. By immunohistochemistry, dermal interstitial dendritic cells (iDCs) and macrophages were CD204+/E-cadherin-, while epidermal Langerhans cells (LCs) were CD204-/E-cadherin+. Neoplastic cells of 4 FPH and 18 HS were CD204+/E-cadherin- (iDC/macrophage immunophenotype), while 2 FPH and 2 HS were CD204-/E-cadherin+ (LC immunophenotype), and 5 HS were CD204+/E-cadherin+ (LC-like cell immunophenotype). Furthermore, immunohistochemical and western blot analyses of AS-FPH01 cells derived from E-cadherin-negative FPH revealed that cultured cells were immunopositive for both CD204 and E-cadherin in vitro and in vivo. These results indicate that the neoplastic cells of feline HS and FPH were variably positive for iDC/macrophage and LC markers, and their immunophenotype changed in different microenvironments. The novel cell line established in the present study may serve as an experimental model of FPH that will enable further molecular and therapeutic studies on this disease.