Choline metabolism reprogramming mediates an immunosuppressive microenvironment in non-small cell lung cancer (NSCLC) by promoting tumor-associated macrophage functional polarization and endothelial cell proliferation.

INTRODUCTION: Lung cancer is a prevalent malignancy globally, and immunotherapy has revolutionized its treatment. However, resistance to immunotherapy remains a challenge. Abnormal cholinesterase (ChE) activity and choline metabolism are associated with tumor oncogenesis, progression, and poor prognosis in multiple cancers. Yet, the precise mechanism underlying the relationship between ChE, choline metabolism and tumor immune microenvironment in lung cancer, and the response and resistance of immunotherapy still unclear. METHODS: Firstly, 277 advanced non-small cell lung cancer (NSCLC) patients receiving first-line immunotherapy in Sun Yat-sen University Cancer Center were enrolled in the study. Pretreatment and the alteration of ChE after 2 courses of immunotherapy and survival outcomes were collected. Kaplan-Meier survival and cox regression analysis were performed, and nomogram was conducted to identify the prognostic and predicted values. Secondly, choline metabolism-related genes were screened using Cox regression, and a prognostic model was constructed. Functional enrichment analysis and immune microenvironment analysis were also conducted. Lastly, to gain further insights into potential mechanisms, single-cell analysis was performed. RESULTS: Firstly, baseline high level ChE and the elevation of ChE after immunotherapy were significantly associated with better survival outcomes for advanced NSCLC. Constructed nomogram based on the significant variables from the multivariate Cox analysis performed well in discrimination and calibration. Secondly, 4 choline metabolism-related genes (MTHFD1, PDGFB, PIK3R3, CHKB) were screened and developed a risk signature that was found to be related to a poorer prognosis. Further analysis revealed that the choline metabolism-related genes signature was associated with immunosuppressive tumor microenvironment, immune escape and metabolic reprogramming. scRNA-seq showed that MTHFD1 was specifically distributed in tumor-associated macrophages (TAMs), mediating the differentiation and immunosuppressive functions of macrophages, which may potentially impact endothelial cell proliferation and tumor angiogenesis. CONCLUSION: Our study highlights the discovery of ChE as a prognostic marker in advanced NSCLC, suggesting its potential for identifying patients who may benefit from immunotherapy. Additionally, we developed a prognostic signature based on choline metabolism-related genes, revealing the correlation with the immunosuppressive microenvironment and uncovering the role of MTHFD1 in macrophage differentiation and endothelial cell proliferation, providing insights into the intricate workings of choline metabolism in NSCLC pathogenesis.

Downregulation of RCN1 inhibits esophageal squamous cell carcinoma progression and M2 macrophage polarization.

Reticulocalbin 1 (RCN1) is a calcium-binding protein involved in the regulation of calcium homeostasis in the endoplasmic reticulum. The aim of this study was to explore the clinical value and biological role of RCN1 in esophageal squamous cell carcinoma (ESCC). In addition, we investigated the effect of RCN1 on the polarization of tumor-associated macrophages (TAMs). The GSE53625 dataset from the Gene Expression Omnibus database was used to analyze the expression of RCN1 mRNA and its relationship with clinical value and immune cell infiltration. Immunohistochemistry was used to validate the expression of RCN1 and its correlation with clinicopathological characteristics. Subsequently, transwell and cell scratch assays were conducted to evaluate the migration and invasion abilities of ESCC cells. The expression levels of epithelial-mesenchymal transition (EMT)-related proteins were evaluated by western blot, while apoptosis was detected by flow cytometry and western blot. Additionally, qRT‒PCR was utilized to evaluate the role of RCN1 in macrophage polarization. RCN1 was significantly upregulated in ESCC tissues and was closely associated with lymphatic metastasis and a poor prognosis, and was an independent prognostic factor for ESCC in patients. Knockdown of RCN1 significantly inhibited the migration, invasion, and EMT of ESCC cells, and promoted cell apoptosis. In addition, RCN1 downregulation inhibited M2 polarization. RCN1 is upregulated in ESCC patients and is negatively correlated with patient prognosis. Knocking down RCN1 inhibits ESCC progression and M2 polarization. RCN1 can serve as a potential diagnostic and prognostic indicator for ESCC, and targeting RCN1 is a very promising therapeutic strategy.

Spatial distribution of tumor-associated macrophages in an orthotopic prostate cancer mouse model.

Mounting evidence suggests that the immune landscape within prostate tumors influences progression, metastasis, treatment response, and patient outcomes. In this study, we investigated the spatial density of innate immune cell populations within NOD.SCID orthotopic prostate cancer xenografts following microinjection of human DU145 prostate cancer cells. Our laboratory has previously developed nanoscale liposomes that attach to leukocytes via conjugated E-selectin (ES) and kill cancer cells via TNF-related apoptosis inducing ligand (TRAIL). Immunohistochemistry (IHC) staining was performed on tumor samples to identify and quantify leukocyte infiltration for different periods of tumor growth and E-selectin/TRAIL (EST) liposome treatments. We examined the spatial-temporal dynamics of three different immune cell types infiltrating tumors using QuPath image analysis software. IHC staining revealed that F4/80+ tumor-associated macrophages (TAMs) were the most abundant immune cells in all groups, irrespective of time or treatment. The density of TAMs decreased over the course of tumor growth and decreased in response to EST liposome treatments. Intratumoral versus marginal analysis showed a greater presence of TAMs in the marginal regions at 3 weeks of tumor growth which became more evenly distributed over time and in tumors treated with EST liposomes. TUNEL staining indicated that EST liposomes significantly increased cell apoptosis in treated tumors. Additionally, confocal microscopy identified liposome-coated TAMs in both the core and periphery of tumors, highlighting the ability of liposomes to infiltrate tumors by "piggybacking" on macrophages. The results of this study indicate that TAMs represent the majority of innate immune cells within NOD.SCID orthotopic prostate tumors, and spatial density varies widely as a function of tumor size, duration of tumor growth, and treatment of EST liposomes.

Prognostic impact of CD68+ tumor-associated macrophages in hepatocellular carcinoma: A meta-analysis.

BACKGROUND: Evidence from clinical research suggests that the tumor-associated macrophages (TAMs) were associated with prognosis in hepatocellular carcinoma (HCC). The aim of the present meta-analysis was to conduct a qualitative analysis to explore the prognostic value of CD68 + TAMs in HCC. METHODS: This study conducted a systematic search in Pubmed, Embase, the Cochrane Library and China National Knowledge Internet from inception of the databases to November 2023. The hazard ratio (HR) and 95% confidence interval (CI) were calculated employing fixed-effect or random-effect models depending on the heterogeneity of the included trials. The Newcastle-Ottawa Scale was used to evaluate the risk of prejudice. RESULTS: We analyzed 4362 HCC patients. The present research indicated that the expression levels Of CD68 + TAMs were significantly associated with overall survival (OS) (HR = 1.55, 95% CI: 1.30-1.84) and disease-free survival (DFS) (HR = 1.44, 95% CI: 1.17-1.78). Subgroup analysis based on cutoff values showed that the "Median" subgroup showed a pooled HR of 1.66 with a 95% CI ranging from 1.32 to 2.08, which was slightly higher than the "Others" subgroup that exhibited a pooled HR of 1.40 and a 95% CI of 1.07 to 1.84. The "PT" subgroup had the highest pooled HR of 1.68 (95% CI: 1.19-2.37), indicating a worse OS compared to the "IT" (pooled HR: 1.50, 95% CI: 1.13-2.01) and "Mix" (pooled HR: 1.52, 95% CI: 1.03-2.26) subgroups. Moreover, in the sample size-based analysis, studies with more than 100 samples (>100) exhibited a higher pooled HR of 1.57 (95% CI: 1.28 to 1.93) compared to studies with fewer than 100 samples (<100), which had a pooled HR of 1.45 (95% CI: 1.00-2.10). CONCLUSIONS: The analysis suggests that CD68 + TAMs were significantly associated with unfavorable OS and DFS in HCC patients, and may be served as a promising prognostic biomarker in HCC. However, more large-scale trials are needed to study the clinical value of TAMs in HCC.

Upregulation of EMR1 (ADGRE1) by Tumor-Associated Macrophages Promotes Colon Cancer Progression by Activating the JAK2/STAT1,3 Signaling Pathway in Tumor Cells.

Previously, we reported that epidermal growth factor-like module-containing mucin-like hormone receptor-like 1 (EMR1/ADGRE1) is abnormally expressed in colon cancer (CC) and is a risk factor for lymph node metastasis (LNM) and poor recurrence-free survival in patients with abundant tumor-associated macrophages (TAMs). However, the signaling pathways associated with EMR1 expression in CC progression remain unclear. In this study, we aimed to explore the role of EMR1 and its signaling interactions with macrophages in CC progression. Spatial transcriptomics of pT3 microsatellite unstable CC tissues revealed heightened Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling in EMR1-HL CC with LNM compared to EMR1-N CC without LNM. Through in vitro coculture of CC cells with macrophages, EMR1 expression by CC cells was found to be induced by TAMs, ultimately interacting with upregulated JAK/STAT signaling, increasing cell proliferation, migration, and motility, and reducing apoptosis. JAK2/STAT3 inhibition decreased the levels of EMR1, JAK2, STAT1, and STAT3, significantly impeded the proliferation, migration, and mobility of cells, and increased the apoptosis of EMR1+ CC cells compared to their EMR1KO counterparts. Overall, TAMs-induced EMR1 upregulation in CC cells may promote LNM and CC progression via JAK2/STAT1,3 signaling upregulation. This study provides further insights into the molecular mechanisms involving macrophages and intracellular EMR1 expression in CC progression, suggesting its clinical significance and offering potential interventions to enhance patient outcomes.

IFNα-induced BST2+ tumor-associated macrophages facilitate immunosuppression and tumor growth in pancreatic cancer by ERK-CXCL7 signaling.

Pancreatic ductal adenocarcinoma (PDAC) features an immunosuppressive tumor microenvironment (TME) that resists immunotherapy. Tumor-associated macrophages, abundant in the TME, modulate T cell responses. Bone marrow stromal antigen 2-positive (BST2+) macrophages increase in KrasG12D/+; Trp53R172H/+; Pdx1-Cre mouse models during PDAC progression. However, their role in PDAC remains elusive. Our findings reveal a negative correlation between BST2+ macrophage levels and PDAC patient prognosis. Moreover, an increased ratio of exhausted CD8+ T cells is observed in tumors with up-regulated BST2+ macrophages. Mechanistically, BST2+ macrophages secrete CXCL7 through the ERK pathway and bind with CXCR2 to activate the AKT/mTOR pathway, promoting CD8+ T cell exhaustion. The combined blockade of CXCL7 and programmed death-ligand 1 successfully decelerates tumor growth. Additionally, cGAS-STING pathway activation in macrophages induces interferon (IFN)α synthesis leading to BST2 overexpression in the PDAC TME. This study provides insights into IFNα-induced BST2+ macrophages driving an immune-suppressive TME through ERK-CXCL7 signaling to regulate CD8+ T cell exhaustion in PDAC.

Profiling of Tumour-Infiltrating Lymphocytes and Tumour-Associated Macrophages in Ovarian Epithelial Cancer-Relation to Tumour Characteristics and Impact on Prognosis.

Early evidence suggests a strong impact of tumour-infiltrating lymphocytes (TILs) on both the prognosis and clinical behaviour of ovarian cancer. Proven associations, however, have not yet translated to successful immunotherapies and further work in the field is urgently needed. We aimed to analyse the tumour microenvironment of a well-characterised cohort of ovarian cancer samples. Tumour markers were selected owing to their comparative underrepresentation in the current literature. Paraffin-embedded, formalin-fixed tumour tissue blocks of 138 patients representative of the population and including early stage disease were identified, stained for CD3, CD20, CD68 and CD163 and analysed for both the stromal and intertumoral components. Data were statistically analysed in relation to clinical details, histological subtype, borderline vs. malignant status, survival and management received. Mean stromal CD3, total CD3 count, mean stromal CD20 and total CD20 count all correlated negatively with survival. Malignant ovarian tumours consistently demonstrated significantly higher infiltration of all analysed immune cells than borderline tumours. Assessment of the stromal compartment produced a considerably higher proportion of significant results when compared to the intra-tumoural infiltrates. Customary assessment of solely intra-tumoural cells in advanced stage disease patients undergoing primary debulking surgery should be challenged, with recommendations for future scoring systems provided.

Non-apoptotic regulated cell death mediates reprogramming of the tumour immune microenvironment by macrophages.

Tumour immune microenvironment (TIME) plays an indispensable role in tumour progression, and tumour-associated macrophages (TAMs) are the most abundant immune cells in TIME. Non-apoptotic regulated cell death (RCD) can avoid the influence of tumour apoptosis resistance on anti-tumour immune response. Specifically, autophagy, ferroptosis, pyroptosis and necroptosis mediate the crosstalk between TAMs and tumour cells in TIME, thus reprogram TIME and affect the progress of tumour. In addition, although some achievements have been made in immune checkpoint inhibitors (ICIs), there is still defect that ICIs are only effective for some people because non-apoptotic RCD can bypass the apoptosis resistance of tumour. As a result, ICIs combined with targeting non-apoptotic RCD may be a promising solution. In this paper, the basic molecular mechanism of non-apoptotic RCD, the way in which non-apoptotic RCD mediates crosstalk between TAMs and tumour cells to reprogram TIME, and the latest research progress in targeting non-apoptotic RCD and ICIs are reviewed.

Surgical tumor-derived nanoplatform targets tumor-associated macrophage for personalized postsurgical cancer immunotherapy.

Directly activating CD8+ T cells within the tumor through antigen-presenting cells (APCs) hold promise for tumor elimination. However, M2-like tumor-associated macrophages (TAMs), the most abundant APCs in tumors, hinder CD8+ T cell activation due to inefficient antigen cross-presentation. Here, we demonstrated a personalized nanotherapeutic platform using surgical tumor-derived galactose ligand-modified cancer cell membrane (CM)-coated cysteine protease inhibitor (E64)-loaded mesoporous silica nanoparticles for postsurgical cancer immunotherapy. The platform targeted M2-like TAMs and released E64 within lysosomes, which reshaped antigen cross-presentation and directly activated CD8+ T cells, thus suppressing B16-OVA melanoma growth. Furthermore, this platform, in combination with anti-PD-L1 antibodies, enhanced the therapeutic efficacy and substantially inhibited 4T1 tumor growth. CMs obtained from surgically resected tumors were used to construct a personalized nanotherapeutic platform, which, in synergy with immune checkpoint blockade (ICB), effectively inhibited postsurgical tumor recurrence in 4T1 tumor. Our work offered a robust, safe strategy for cancer immunotherapy and prevention of postsurgical tumor recurrence.

Lentinan inhibits cell invasion via M2 polarization of tumor-associated macrophages and Wnt/ß-catenin signaling in non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) is an aggressive and devastating cancer due to its metastasis induced by increased invasion. Lentinan is a polysaccharide exerting antitumor roles in multiple cancers, including lung cancer. However, the influence of lentinan on cell invasion in NSCLC remains unclear. Cell invasion was detected by transwell analysis. Matrix metallopeptidase 9 (MMP9) levels were measured through immunofluorescence staining. The markers arginase-1 (Arg-1), CD206 and interleukin (IL)-10 (IL-10) of M2 macrophages, Wnt3a, and ß-catenin levels were measured by western blot or enzyme linked immunosorbent assay. Lentinan did not affect cell viability and proliferation in NSCLC cells. Lentinan suppressed cell invasion and reduced the expression and secretion of MMP9. Lentinan attenuated also M2 polarization of tumor-associated macrophages. Moreover, lentinan mitigated the M2 macrophage conditioned medium-mediated cell invasion and MMP9 alterations in NSCLC cells. Lentinan inhibited the activation of the Wnt/ß-catenin signaling in NSCLC cells. The activated Wnt/ß-catenin pathway reversed the suppressive effects of lentinan on cell invasion and MMP9 level in NSCLC cells. In conclusion, lentinan reduces cell invasion in NSCLC cells by inhibiting the M2 polarization of tumor-associated macrophages and the Wnt/ß-catenin signaling.

The regulatory role of autophagy between TAMs and tumor cells.

Cancer has become a global public health problem and its harmful effects have received widespread attention. Conventional treatments such as surgical resection, radiotherapy and other techniques are applicable to clinical practice, but new drugs are constantly being developed and other therapeutic approaches, such as immunotherapy are being applied. In addition to studying the effects on individual tumor cells, it is important to explore the role of tumor microenvironment on tumor cell development since tumor cells do not exist alone but in the tumor microenvironment. In the tumor microenvironment, tumor cells are interconnected with other stromal cells and influence each other, among which tumor-associated macrophages (TAMs) are the most numerous immune cells. At the same time, it was found that cancer cells have different levels of autophagy from normal cells. In cancer therapy, the occurrence of autophagy plays an important role in promoting tumor cell death or inhibiting tumor cell death, and is closely related to the environment. Therefore, elucidating the regulatory role of autophagy between TAMs and tumor cells may be an important breakthrough, providing new perspectives for further research on antitumor immune mechanisms and improving the efficacy of cancer immunotherapy.

Exosome-transmitted podoplanin promotes tumor-associated macrophage-mediated immune tolerance in glioblastoma.

AIMS: Glioblastoma is the most frequent and aggressive primary brain tumor, characterized by rapid disease course and poor treatment responsiveness. The abundance of immunosuppressive macrophages in glioblastoma challenges the efficacy of novel immunotherapy. METHODS: Bulk RNA-seq and single-cell RNA-seq of glioma patients from public databases were comprehensively analyzed to illustrate macrophage infiltration patterns and molecular characteristics of podoplanin (PDPN). Multiplexed fluorescence immunohistochemistry staining of PDPN, GFAP, CD68, and CD163 were performed in glioma tissue microarray. The impact of PDPN on macrophage immunosuppressive polarization was investigated using a co-culture system. Bone marrow-derived macrophages (BMDMs) and OT-II T cells isolated from BALB/c and OT-II mice respectively were co-cultured to determine T-cell adherence. Pathway alterations were probed through RNA sequencing and western blot analyses. RESULTS: Our findings demonstrated that PDPN is notably correlated with the expression of CD68 and CD163 in glioma tissues. Additionally, macrophages phagocytosing PDPN-containing EVs (EVsPDPN ) from GBM cells presented increased CD163 expression and augmented secretion of immunoregulatory cytokine (IL-6, IL-10, TNF-α, and TGF-ß1). PDPN within EVs was also associated with enhanced phagocytic activity and reduced MHC II expression in macrophages, compromising CD4+ T-cell activation. CONCLUSIONS: This investigation underscores that EVsPDPN derived from glioblastoma cells contributes to M2 macrophage-mediated immunosuppression and is a potential prognostic marker and therapeutic target in glioblastoma.

Specific lineage transition of tumor-associated macrophages elicits immune evasion of ascitic tumor cells in gastric cancer with peritoneal metastasis.

BACKGROUND: Gastric cancer with peritoneal metastasis (PM-GC), recognized as one of the deadliest cancers. However, whether and how the tumor cell-extrinsic tumor microenvironment (TME) is involved in the therapeutic failure remains unknown. Thus, this study systematically assessed the immunosuppressive tumor microenvironment in ascites from patients with PM-GC, and its contribution to dissemination and immune evasion of ascites-disseminated tumor cells (aDTCs). METHODS: Sixty-three ascites and 43 peripheral blood (PB) samples from 51 patients with PM-GC were included in this study. aDTCs in ascites and circulating tumor cells (CTCs) in paired PB were immunophenotypically profiled. Using single-cell RNA transcriptional sequencing (scRNA-seq), crosstalk between aDTCs and the TME features of ascites was inspected. Further studies on the mechanism underlying aDTCs-immune cells crosstalk were performed on in vitro cultured aDTCs. RESULTS: Immune cells in ascites interact with aDTCs, prompting their immune evasion. Specifically, we found that the tumor-associated macrophages (TAMs) in ascites underwent a continuum lineage transition from cathepsinhigh (CTShigh) to complement 1qhigh (C1Qhigh) TAM. CTShigh TAM initially attracted the metastatic tumor cells to ascites, thereafter, transitioning terminally to C1Qhigh TAM to trigger overproliferation and immune escape of aDTCs. Mechanistically, we demonstrated that C1Qhigh TAMs significantly enhanced the expression of PD-L1 and NECTIN2 on aDTCs, which was driven by the activation of the C1q-mediated complement pathway. CONCLUSIONS: For the first time, we identified an immunosuppressive macrophage transition from CTShigh to C1Qhigh TAM in ascites from patients with PM-GC. This may contribute to developing potential TAM-targeted immunotherapies for PM-GC.

Prognostic and clinical significance of tumor-associated macrophages in esophageal squamous cell carcinoma after surgery: do biomarkers and distributions matter?

BACKGROUND: The role of tumor-associated macrophages (TAMs) in patients with esophageal squamous cell carcinoma (ESCC) following surgery remains controversial. Hence, we performed the present study to systematically analyze the prognostic and clinical significance of distinct TAMs biomarkers and distributions in ESCC patients underwent surgery. METHODS: PubMed, Web of Science, and EMBASE databases were searched up to March 31, 2023. The pooled analysis was conducted to evaluate the effects of TAMs on overall survival (OS), disease-free survival (DFS), and clinicopathological characteristics using fixed-effects or random-effect model. RESULTS: Involving a total of 2,502 ESCC patients underwent surgery from 15 studies, the results suggested that the total count of CD68+ TAMs was inversely associated with OS and DFS in ESCC patients, which was also noticed in the relationship of CD68+ TAMs in tumor islet (TI) with OS (all P<0.05), although no association between CD68+ TAMs in tumor stroma (TS) and OS (P>0.05). Moreover, either islet or stromal CD163+ TAMs density was a prognostic factor ESCC (all P<0.05). Similarly, an elevated CD204+ TAMs density in TI predicted a poor DFS (P<0.05), although CD204+ TAMs in TI had no relationship with OS (P>0.05). Besides, a high CD68+ TAMs density was significantly associated with lymphatic vessel invasion, vascular invasion, and lymph node metastasis (all P<0.05). CONCLUSION: Our results demonstrated the prognostic and clinical significance of TAMs in ESCC patients underwent surgery. TAMs should be considered a target that could improve prognostic stratification and clinical outcomes in ESCC after surgery.

Tumor-associated macrophages in non-small-cell lung cancer: From treatment resistance mechanisms to therapeutic targets.

Non-small cell lung cancer (NSCLC) remains one of the leading causes of cancer-related deaths worldwide. Different treatment approaches are typically employed based on the stage of NSCLC. Common clinical treatment methods include surgical resection, drug therapy, and radiation therapy. However, with the introduction and utilization of immune checkpoint inhibitors, cancer treatment has entered a new era, completely revolutionizing the treatment landscape for various cancers and significantly improving overall patient survival. Concurrently, treatment resistance often poses a critical challenge, with many patients experiencing disease progression following an initial response due to treatment resistance. Increasing evidence suggests that the tumor microenvironment (TME) plays a pivotal role in treatment resistance. Tumor-associated macrophages (TAMs) within the TME can promote treatment resistance in NSCLC by secreting various cytokines activating signaling pathways, and interacting with other immune cells. Therefore, this article will focus on elucidating the key mechanisms of TAMs in treatment resistance and analyze how targeting TAMs can reduce the levels of treatment resistance in NSCLC, providing a comprehensive understanding of the principles and approaches to overcome treatment resistance in NSCLC.

Programmed Cell Death Ligand 1 Expression in CD163 + Tumor-associated Macrophages in Cancer Gland Rupture Microenvironment.

In this study, we aimed to examine the relationship among cancer gland rupture microenvironment, programmed cell death ligand 1 (PD-L1) expression in CD163 + tumor-associated macrophages (TAMs), and prognosis in colon adenocarcinoma. A total of 122 patients were diagnosed with colon adenocarcinoma between 2010 and 2019. PD-L1 + (clone 22C3) "macrophage scores" in the microenvironment of cancer gland rupture were calculated. The effects of these variables on prognosis were statistically analyzed. CD163 + TAMs were denser in the cancer gland rupture microenvironment. PD-L1 + TAMs were observed in the tumor periphery, and there was a significant difference between the rates of PD-L1 expression in TAMs and survival time (log-rank = 10.46, P = 0.015), clinical stage 2 ( P = 0.038), and primary tumor 3 and primary tumor 4 cases ( P = 0.004, P = 0.013). The risk of mortality was 4.070 times higher in patients with a PD-L1 expression rate of ≥1% in CD163 + TAMs. High PD-L1 expression in CD163 + TAMs is associated with poor overall survival. Therefore, blocking PD-L1 in CD163 + TAMs can be used as a target for immunotherapy.

Expression of CD68+ Tumor associated macrophages in relation to ß-catenin in carcinoma stomach.

Background: With no unified system for tumor associated macrophages (TAMs) density assessment, limited information is available on their relationship with ß-catenin expression. Aim: To evaluate the density of CD68+ TAMs in gastric adenocarcinoma samples by immunohistochemistry and correlate it with grade, stage, invasion, and beta-catenin. Designs and Settings: Formalin fixed paraffin embedded (FFPE) blocks from gastrectomy specimens of proven gastric adenocarcinoma were prospectively and retrospectively were studied over a period of two years. Materials and Methods: Immunohistochemistry with CD68 and ß-catenin was performed. TAM density was qualitatively compared in "tumor" versus "stroma" and "tumor" versus "non-tumor" regions. Quantitative CD68+ TAM density was assessed using different methods and compared. Cases were classified as high and low TAM based on the median value and correlated with histologic type, location, grade, stage and ß-catenin expression pattern. Statistical Analysis: Spearman's rank correlation test was used to compare the different methods of TAM density evaluation. The categorical variables were studied using Pearson's Chi-square or Fisher's exact test. CD68+ TAM density and ß-catenin expression were correlated by analysis of variance. A P value ≤ 0.05 was taken as statistically significant. Results: The CD68+ TAMs in the "tumor" versus "non-tumor" area (p = 0.34) and "tumor" versus "stroma distribution" (p = 0.81) did not show any statistical significance. All methods of TAM density were found to be comparable. High TAM group is significantly associated with lymphovascular invasion, tumor depth, lymph node metastasis, and abnormal ß-catenin expression. Conclusion: TAMs density plays an important role in the tumor stage. Macrophages may possibly induce gastric cancer invasiveness by activating ß-catenin pathway.

Regulation of regulatory T cells and tumor-associated macrophages in gastric cancer tumor microenvironment.

INTRODUCTION: Despite advancements in the methods for prevention and early diagnosis of gastric cancer (GC), GC continues to be the fifth in incidence among major cancers and the third most common cause of cancer-related death. The therapeutic effects of surgery and drug treatment are still unsatisfied and show notable differences according to the tumor microenvironment (TME) of GC. METHODS: Through screening Pubmed, Embase, and Web of Science, we identified and summarized the content of recent studies that focus on the investigation of Helicobacter pylori (Hp) infection, regulatory T cells (Tregs), and tumor-associated macrophages (TAMs) in the TME of GC. Furthermore, we searched and outlined the clinical research progress of various targeted drugs in GC treatment including CTLA-4, PD-1\PD-L1, and VEGF/VEGFR. RESULTS: In this review, the findings indicate that Hp infection causes local inflammation and leads to immunosuppressive environment. High Tregs infiltration in the TME of GC is associated with increased induction and recruitment; the exact function of infiltrated Tregs in GC was also affected by phenotypes and immunosuppressive molecules. TAMs promote the development and metastasis of tumors, the induction, recruitment, and function of TAMs in the TME of gastric cancer are also regulated by various factors. CONCLUSION: Discussing the distinct tumor immune microenvironment (TIME) of GC can deepen our understanding on the mechanism of cancer immune evasion, invasion, and metastasis, help us to reduce the incidence of GC, and guide the innovation of new therapeutic targets for GC eventually.

Neutrophil-lymphocyte ratio reflects tumour-infiltrating lymphocytes and tumour-associated macrophages and independently predicts poor outcome in breast cancers with neoadjuvant chemotherapy.

AIMS: The neutrophil-lymphocyte ratio (NLR) is a systemic reflection of cancer-associated inflammation and a prognostic marker for breast cancer. For the local tumour microenvironment, tumour-infiltrating lymphocytes (TILs) and tumour-associated macrophages (TAMs) are also highly correlated with breast cancer survival. This study aimed to explore the relationship between the circulating and local immune microenvironment, and to further delineate the prognostic role of NLR in breast cancer patients receiving neoadjuvant chemotherapy (NAC). METHODS: A cohort of breast cancer patients receiving NAC with subsequent surgery was retrieved. Clinical data were reviewed. Histological slides and CD8 immunohistochemistry from biopsy (pre-chemotherapy) and excision (postchemotherapy) specimens were assessed for TILs and TAMs. RESULTS: A total of 146 patients were included. There was a significant positive correlation between pre- and postsurgery NLR at a cut-off of 2.6 (median pre-chemotherapy NLR) (P < 0.001). NLR pre-chemotherapy was associated positively with necrosis on biopsy (P = 0.027) and excision (P = 0.021) and TAMs on excision (P = 0.049). NLR 1 year postsurgery was associated with high tumour stage (P = 0.050) and low histological grade (P = 0.008). TIL count was lower in NLR-high cases at almost all time-points by histological assessment and CD8 immunostaining (P < 0.050). In multivariate analysis, postsurgery NLR is an independent predictor for overall survival [OS; hazard ratio (HR) = 9.524, P < 0.001], breast cancer-specific survival (BCSS) (HR = 10.059, P = 0.001) and disease-free survival (DFS; HR = 2.824, P = 0.016). CONCLUSIONS: The association between NLR with tumour necrosis, TAMs and TILs illustrates an interaction between the circulating and local immune microenvironment. Late NLR is a strong indicator of outcome and may be useful for prognostication and disease monitoring.