Effect of macrophages on breast cancer cell proliferation, and on expression of hormone receptors, uPAR and HER-2

Macrophage subtypes inhibit breast cancer proliferation in culture

Macrophages are a highly plastic cell type that adopt distinct subtypes and functional states depending on environmental cues. These functional states can vary widely, with distinct macrophages capable of displaying opposing functions. We sought to understand how macrophage subtypes that exist on two ends of a spectrum influence the function of other cells. We used a coculture system with primary human macrophages to probe the effects of macrophage subtypes on breast cancer cell proliferation. Our studies revealed a surprising phenotype in which both macrophage subtypes inhibited cancer cell proliferation compared with cancer cells alone. Of particular interest, using two different proliferation assays with two different breast cancer cell lines, we showed that differentiating macrophages into a "protumor" subtype inhibited breast cancer cell proliferation. These findings are inconsistent with the prevailing interpretation that "protumor" macrophages promote cancer cell proliferation and suggest a re-evaluation of how these interpretations are made.

Is overexpression of CD163 and CD47 in tumour cells of breast carcinoma implicated in the recruitment of tumour-associated macrophages (TAMs) in tumour microenvironment? immunohistochemical prognostic study

BACKGROUND

Now, targeted therapy and immunotherapy are promoted. tumour -Associated Macrophages (TAMs) are an essential component of immune-response in breast cancer(BC) with prognostic controversy. Additionally, their recruiting factors are still obscure. Purpose:This study aimed to evaluate the prognostic significance of CD163 and CD47 in BC of No Special Type (BC-NST) and to explore their suggested role in recruiting TAMs.

MATERIAL AND METHODS

This immunohistochemical study was conducted on 91 archival specimens of breast cases. Immunoreactivity scores were correlated with TAMs density, clinicopathological data, and survival.

RESULTS

Revealed the highest CD163 expression was detected in the pure DCIS group (p = 0.016), while the highest CD47 expression and high TAMs density were reported in the invasive group (p = 0.008, and p = 0.002 respectively) followed by the DCIS group. In IC-NSTs the CD163 and CD47 scores were associated with poor prognostic parameters like(high grade, advanced stage, distant metastasis, ER negativity,Ki67 index, post-surgical chemotherapy, poor NPI group, high mitotic count, dense infiltration of TAMs, shorter OS). Also, CD47 was associated with the dens infiltration of TAMs in DCIS (p = 0.001). There was a significant correlation between tumour cell expression of CD163 and CD47 in IC-NSTs and DCIS (p = 0.002 and p = 0.009 respectively).

CONCLUSIONS

High CD163 and CD47 expressions in both DCIS andIBC are intimately associated, significantly associated with poor prognosis and are important provoking factors of TAMs.

Immunohistochemical Expression of CD47 and CD68 in Breast Carcinoma and Their Prognostic Value

BACKGROUND

Cluster of differentiation 47 (CD47) has been identified as a new immune checkpoint. The exact role of CD47 in prognosis of breast cancer remains unclear. This study aims to evaluate immunohistochemical (IHC) expression of CD47 in breast cancer, and to measure the density of tumor associated macrophages (TAMs) infiltration by CD68 IHC staining. Furthermore, assessing the relations of CD47 and CD68 expression to different clinicopathological variables and evaluating the prognostic role of CD47 and CD68 in breast cancer cases.

METHODS

This retrospective cohort study included 200 diagnosed primary breast cancer cases who underwent surgical resection at the Oncology Center of Mansoura University (OCMU), Faculty of Medicine, Egypt. Clinicopathological and survival data were collected. IHC for CD47 and CD68 was performed.

RESULTS

Among 200 breast cancer cases, high CD47 expression was detected in 89 cases (44.5%). CD47 high expression was significantly associated with presence of distant metastasis (P=0.04), advanced TNM stage (P=0.02), ER & PR negativity (P=0.04 & 0.004 respectively), and molecular subtype (P=0.03). Their was a statistically significant association between CD47 and CD68 expression (P=0.002). CD47 high expression was found to predict poor overall survival, but it is not considered alone as independent poor prognostic factor by multivariate analysis. Multivariate analysis spotted combined high expression of CD47 and CD68 as an independent prognostic predictor for shorter OS in breast cancer patients (P=0.002).

CONCLUSION

CD47 high expression is related to poor prognosis in breast cancer patients especially when associated with high CD68+TAMs infiltration. Therefore, CD47 is a promising prognostic and therapeutic target in breast carcinoma that may direct selection of patients for immunotherapy.

Macrophage subtypes inhibit breast cancer proliferation in culture

Macrophages are a highly plastic cell type that adopt distinct subtypes and functional states depending on environmental cues. These functional states can vary wildly, with distinct macrophages capable of displaying opposing functions. We sought to understand how macrophage subtypes that exist on two ends of a spectrum influence the function of other cells. We used a co-culture system with primary human macrophages to probe the effects of macrophage subtypes on breast cancer cell proliferation. Our studies revealed a surprising phenotype in which both macrophage subtypes inhibited cancer cell proliferation compared to cancer cells alone. Of particular interest, using two different proliferation assays with two different breast cancer cell lines, we showed that differentiating macrophages into a "pro-tumor" subtype inhibited breast cancer cell proliferation. These findings are inconsistent with the prevailing interpretation that "pro-tumor" macrophages promote cancer cell proliferation and suggest a re-evaluation of how these interpretations are made.

uPAR (PLAUR) Marks Two Intra-Tumoral Subtypes of Glioblastoma: Insights from Single-Cell RNA Sequencing

Urokinase plasminogen activator receptor (uPAR) encoded by the PLAUR gene is known as a clinical marker for cell invasiveness in glioblastoma multiforme (GBM). It is additionally implicated in various processes, including angiogenesis and inflammation within the tumor microenvironment. However, there has not been a comprehensive study that depicts the overall functions and molecular cooperators of PLAUR with respect to intra-tumoral subtypes of GBM. Using single-cell RNA sequencing data from 37 GBM patients, we identified PLAUR as a marker gene for two distinct subtypes in GBM. One subtype is featured by inflammatory activities and the other subtype is marked by ECM remodeling processes. Using the whole-transcriptome data from single cells, we are able to uncover the molecular cooperators of PLAUR for both subtypes without presuming biological pathways. Two protein networks comprise the molecular context of PLAUR, with each of the two subtypes characterized by a different dominant network. We concluded that targeting PLAUR directly influences the mechanisms represented by these two protein networks, regardless of the subtype of the targeted cell.

Clinical significance, molecular characterization, and immune microenvironment analysis of coagulation-related genes in clear cell renal cell carcinoma

Background

Numerous studies have revealed a tight connection between tumor development and the coagulation system. However, the effects of coagulation on the prognosis and tumor microenvironment (TME) of clear cell renal cell carcinoma (ccRCC) remain poorly understood.

Methods

We employed the consensus clustering method to characterize distinct molecular subtypes associated with coagulation patterns. Subsequently, we examined variations in the overall survival (OS), genomic profiles, and TME characteristics between these subtypes. To develop a prognostic coagulation-related risk score (CRRS) model, we utilized the least absolute shrinkage and selection operator Cox regression and stepwise multivariate Cox regression analyses. We also created a nomogram to aid in the clinical application of the risk score, evaluating the relationships between the CRRS and the immune microenvironment, responsiveness to immunotherapy, and targeted treatment. The clinical significance of PLAUR and its biological function in ccRCC were also further analyzed.

Results

There were significant differences in clinical features, prognostic stratification, genomic variation, and TME characteristics between the two coagulation-related subtypes. We established and validated a CRRS using six coagulation-related genes that can be employed as an effective indicator of risk stratification and prognosis estimation for ccRCC patients. Significant variations in survival outcomes were observed between the high- and low-risk groups. The nomogram was proficient in predicting the 1-, 3-, and 5-year OS. Additionally, the CRRS emerged as a novel tool for evaluating the clinical effectiveness of immunotherapy and targeted treatments in ccRCC. Moreover, we confirmed upregulated PLAUR expression in ccRCC samples that was significantly correlated with poor patient prognosis. PLAUR knockdown notably inhibited ccRCC cell proliferation and migration.

Conclusion

Our data suggested that CRRS may be employed as a reliable predictive biomarker that can provide therapeutic benefits for immunotherapy and targeted therapy in ccRCC.

Evaluation of Number Density of Tumor-Associated Macrophages by Immunohistochemistry and Semiquantitative Scoring in Invasive Breast Cancer: An Indian Study

Context

Tumor microenvironment is emerging as a critical factor for progression of breast cancer. Tumor-associated macrophages (TAMs) play an important role in promoting tumor growth.

Aim

This study was aimed at correlation of number density (ND) of TAMs with invasive ductal carcinoma (IDC) grading utilizing an image morphometric technique. We also sought to compare the TAMs and ND in the tumoral area and stromal region. We also explored the relationship between the clinical and pathological prognostic parameters.

Subjects and Methods

The study included 75 cases of IDC that had undergone modified radical mastectomy. The Institutional Ethics Committee approved the study. Samples were classified as Grade 1, 2, and 3. Cases were graded as per the modified Bloom and Richardson criterion. Mean with standard deviation was calculated for each group. We utilized CD68 and CD163 immunostained sections for determining the ND of TAMs. TAMs were evaluated using computerized digital photomicrograph system with image analyzing software. ND was defined as the number of TAMs in total number of TAMs in five high-power fields/total area of five fields. ND was calculated separately in tumor and tumor stroma (TS). Estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2/neu (HER2/neu) were scored in accordance with recommendations. Ki-67 was scored as per the recommended guidelines.

Statistical Analysis Used

Data were tabulated in Microsoft Excel. SPSS version 20.0 (IBM Corp., Armonk, NY, USA) was used for statistical analysis. To determine the relationship between macrophage density and clinicopathologic parameters, we used the independent t-test. To determine the differences in the parameters, analysis of variance (ANOVA) was utilized.

Results

Age of the patients ranged from 34 to 58 years (mean: 55.5). One-way ANOVA between various grades of tumor indicating significant differences in terms of CD68 and CD163 densities in tumor and stroma (P < 0.0001). i.e., significant increased density of CD68 and CD163 was observed in Grade 3 tumor as compared to other two groups. A greater histological grade, ER, PR negative status, and a high Ki-67 index were all associated with TAM ND. There was no relation to HER2/neu status. Result of unpaired t-test indicates increased density in stroma as compared to tumor among various grades of IDC.

Conclusions

We analyzed images with a software using photographs of the stained slides. This helped in quantitative analysis of TAMs on the CD68 and CD163 stained sections. This approach standardizes and reproducibly counts TAMs per unit area. We found significant difference between the number densities of TAMs in grades of invasive breast carcinoma. There were statistically significant differences in numerical densities of TAMs with ER, PR negativity, and Ki-67. There was no correlation with HER2/neu. Densities of CD68 and CD163 densities are more prevalent in TS as compared to intratumoral region.

Macrophages and Urokinase Plasminogen Activator Receptor System in Multiple Myeloma: Case Series and Literature Review

The microenvironment plays an essential role in multiple myeloma (MM) development, progression, cell proliferation, survival, immunological escape, and drug resistance. Mesenchymal stromal cells and macrophages release tolerogenic cytokines and favor anti-apoptotic signaling pathway activation, while the urokinase plasminogen activator receptor (uPAR) system contributes to migration through an extracellular matrix. Here, we first summarized the role of macrophages and the uPAR system in MM pathogenesis, and then we reported the potential therapeutic effects of uPAR inhibitors in a case series of primary MM-derived adherent cells. Our preliminary results showed that after uPAR inhibitor treatments, interleukein-6 (mean ± SD, 8734.95 ± 4169.2 pg/mL vs. 359.26 ± 393.8 pg/mL, pre- vs. post-treatment; p = 0.0012) and DKK-1 levels (mean ± SD, 7005.41 ± 6393.4 pg/mL vs. 61.74 ± 55.2 pg/mL, pre- vs. post-treatment; p = 0.0043) in culture medium were almost completely abolished, supporting further investigation of uPAR blockade as a therapeutic strategy for MM treatment. Therefore, uPAR inhibitors could exert both anti-inflammatory and pro-immunosurveillance activity. However, our preliminary results need further validation in additional in vitro and in vivo studies.

Elevated LILRB1 expression predicts poor prognosis and is associated with tumor immune infiltration in patients with glioma

BACKGROUND

Leukocyte immunoglobulin-like receptor subfamily B1 (LILRB1) is regarded as an inhibitory molecule. However, the importance of LILRB1 expression in glioma has not yet been determined. This investigation examined the immunological signature, clinicopathological importance and prognostic value of LILRB1 expression in glioma.

METHODS

We used data from the UCSC XENA database, the Cancer Genome Atlas (TCGA) database, the Chinese Glioma Genome Atlas (CGGA) database, the STRING database, the MEXPRESS database and our clinical glioma samples to perform bioinformatic analysis and used vitro experiments to examine the predictive value and potential biological roles of LILRB1 in glioma.

RESULTS

Higher LILRB1 expression was considerably present in the higher WHO grade glioma group and was linked to a poorer prognosis in patients with glioma. Gene set enrichment analysis (GSEA) revealed that LILRB1 was positively correlated with the JAK/STAT signaling pathway. LILRB1 combined with tumor mutational burden (TMB) and microsatellite instability (MSI) may be a promising indicator for the effectiveness of immunotherapy in patients with glioma. Increased LILRB1 expression was positively linked with the hypomethylation, M2 macrophage infiltration, immune checkpoints (ICPs) and M2 macrophage makers. Univariate and multivariate Cox regression analyses determined that increased LILRB1 expression was a standalone causal factor for glioma. Vitro experiments determined that LILRB1 positively enhanced the proliferation, migration and invasion in glioma cells. MRI images demonstrated that higher LILRB1 expression was related with larger tumor volume in patients with glioma.

CONCLUSION

Dysregulation of LILRB1 in glioma is correlated with immune infiltration and is a standalone causal factor for glioma.

RNA-seq and ATAC-seq analysis of CD163+ macrophage-induced progestin-insensitive endometrial cancer cells

BACKGROUND

Progestins are used as fertility-sparing regimens for young patients with stage 1A endometrioid endometrial cancer (EEC) and atypical endometrial hyperplasia (AEH). CD163⁺ macrophages promote estrogen-dependent EEC development, but whether they induce progestin insensitivity remains unclear. This study aimed to investigate the possible effects of CD163⁺ macrophages on progestin response in AEH/EEC patients.

METHODS

The number of infiltrating CD163⁺ macrophages in progestin-insensitive and -sensitive endometrial lesions was compared. The effects of CD163⁺ macrophages on progestin responses and progesterone receptor (PR) expression in EC cells were evaluated in vitro. ATAC-seq and RNA-seq were combined to identify molecular/biological changes induced by CD163⁺ macrophages in progestin-insensitive EC cells.

RESULTS

Increased CD163⁺ macrophage infiltration was significantly associated with progestin insensitivity and longer treatment durations in AEH/EEC patients. Additionally, the number of CD163⁺ macrophages was negatively correlated with PR expression in AEH/EEC tissues. Furthermore, the CD163⁺ macrophage-mediated microenvironment and secreted cytokines downregulated PR expression and impaired the response of EC cells to medroxyprogesterone acetate (MPA). RNA-seq analysis demonstrated that CD163⁺ macrophages antagonized PR signaling by blocking or even reversing MPA-regulated differential gene expression. Based on RNA-seq and ATAC-seq analyses, extracellular matrix (ECM) signaling and ECM-related transcription factors, FOXF2, POU1F1, and RUNX1were identified to potentially be involved in CD163⁺ macrophage-induced progestin insensitivity in endometrial cancer patients.

CONCLUSIONS

We identified CD163⁺ macrophages as an important mediator of progestin desensitization and an unfavorable factor for the efficacy of fertility-preserving treatment in AEH/EEC patients.

Diversity and heterogeneity in human breast cancer adipose tissue revealed at single-nucleus resolution

Introduction

There is increasing awareness of the role of adipose tissue in breast cancer occurrence and development, but no comparison of adipose adjacent to breast cancer tissues and adipose adjacent to normal breast tissues has been reported.

Methods

Single-nucleus RNA sequencing (snRNA-seq) was used to analyze cancer-adjacent and normal adipose tissues from the same breast cancer patient to characterize heterogeneity. SnRNA-seq was performed on 54513 cells from six samples of normal breast adipose tissue (N) distant from the tumor and tumor-adjacent adipose tissue (T) from the three patients (all surgically resected).

Results and discussion

Significant diversity was detected in cell subgroups, differentiation status and, gene expression profiles. Breast cancer induces inflammatory gene profiles in most adipose cell types, such as macrophages, endothelial cells, and adipocytes. Furthermore, breast cancer decreased lipid uptake and the lipolytic phenotype and caused a switch to lipid biosynthesis and an inflammatory state in adipocytes. The in vivo trajectory of adipogenesis revealed distinct transcriptional stages. Breast cancer induced reprogramming across many cell types in breast cancer adipose tissues. Cellular remodeling was investigated by alterations in cell proportions, transcriptional profiles and cell-cell interactions. Breast cancer biology and novel biomarkers and therapy targets may be exposed.

Reinventing the human tuberculosis (TB) granuloma: Learning from the cancer field

Tuberculosis (TB) remains one of the deadliest infectious diseases in the world and every 20 seconds a person dies from TB. An important attribute of human TB is induction of a granulomatous inflammation that creates a dynamic range of local microenvironments in infected organs, where the immune responses may be considerably different compared to the systemic circulation. New and improved technologies for in situ quantification and multimodal imaging of mRNA transcripts and protein expression at the single-cell level have enabled significantly improved insights into the local TB granuloma microenvironment. Here, we review the most recent data on regulation of immunity in the TB granuloma with an enhanced focus on selected in situ studies that enable spatial mapping of immune cell phenotypes and functions. We take advantage of the conceptual framework of the cancer-immunity cycle to speculate how local T cell responses may be enhanced in the granuloma microenvironment at the site of Mycobacterium tuberculosis infection. This includes an exploratory definition of "hot", immune-inflamed, and "cold", immune-excluded TB granulomas that does not refer to the level of bacterial replication or metabolic activity, but to the relative infiltration of T cells into the infected lesions. Finally, we reflect on the current knowledge and controversy related to reactivation of active TB in cancer patients treated with immune checkpoint inhibitors such as PD-1/PD-L1 and CTLA-4. An understanding of the underlying mechanisms involved in the induction and maintenance or disruption of immunoregulation in the TB granuloma microenvironment may provide new avenues for host-directed therapies that can support standard antibiotic treatment of persistent TB disease.

Agri-Food By-Products in Cancer: New Targets and Strategies

The globalization and the changes in consumer lifestyles are forcing us to face a deep transformation in food demand and in the organization of the entire food production system. In this new era, the food-loss and food-waste security nexus is relevant in the global debate and avoiding unsustainable waste in agri-food systems as well as the supply chain is a big challenge. "Food waste" is useful for the recovery of its valuable components, thus it can assume the connotation of a "food by-product". Sustainable utilization of agri-food waste by-products provides a great opportunity. Increasing evidence shows that agri-food by-products are a source of different bioactive molecules that lower the inflammatory state and, hence, the aggressiveness of several proliferative diseases. This review aims to summarize the effects of agri-food by-products derivatives, already recognized as promising therapeutics in human diseases, including different cancer types, such as breast, prostate, and colorectal cancer. Here, we examine products modulating or interfering in the signaling mediated by the epidermal growth factor receptor.

Analysis of invasiveness and tumor-associated macrophages infiltration in solid pseudopapillary tumors of pancreas

BACKGROUND

Solid pseudopapillary tumor (SPT) is a rare pancreatic tumor. Considering its malignant behaviors, SPT has been classified as a low-grade malignant tumor. Indeed, only 9.2% of all SPT patients are initially diagnosed as malignant with invasion or metastasis. Thus, one of the challenges in managing SPT patients is predicting malignant behavior.

AIM

To investigate the malignant behavior and tumor-associated macrophage (TAM) infiltration between different histopathologic features of SPT patients.

METHODS

Twenty-five formalin-fixed paraffin-embedded tissue samples from 22 patients pathologically diagnosed with an SPT between 2009 and 2019 at West China Hospital were included in this retrospective study. Integrity of the capsule and growth pattern of the tumor cells was assessed microscopically in hematoxylin-eosin (HE)-stained sections. Based on the histopathological features, the SPT patients were divided into two groups: capsule or invasion. Clinical features, malignant behavior, and TAM infiltration were compared between the two groups.

RESULTS

Among the 22 SPT patients, 11 were identified for each group, having either a capsule or invasion histopathologic feature. Malignant behavior was more frequent in the invasion group, including 2 patients who had peripheral organ invasion, 3 with liver metastasis, and 1 with both lymph node and spleen metastases (P= 0.045). Ki-67 index of more than 3% was also more frequent in the invasion group (P = 0.045). Immunohistochemical analysis showed that the invasion group had a significant increase of CD68-positive TAMs in intratumor and peritumor sites in comparison with the capsule group (all P < 0.0001). Similarly, CD163-positive M2-like macrophages were also markedly increased in the intratumor and peritumor sites in the invasion group (all P < 0.0001). At the liver metastasis site, both intratumor and peritumor tissues showed relatively high-level CD68-positive TAMs and CD163-positive M2-like macrophages infiltration. However, the differences between the intratumor, peritumor and normal hepatic tissues did not reach statistical significance (all P > 0.05).

CONCLUSION

SPT patients with invasion evident under microscope were more likely to exhibit malignant behavior and TAM infiltration, especially M2-like macrophages. This finding can help in future investigations of the underlying mechanism of TAM-mediated SPT malignant behavior.

Comprehensive analysis of the importance of PLAUR in the progression and immune microenvironment of renal clear cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is a common type of kidney cancer with a high mortality rate, and the discovery of new therapeutic markers is essential to improve patient survival. The plasminogen activator urokinase receptor (PLAUR) plays key roles in tissue remodeling and extracellular matrix degradation, which contribute to invasion and metastasis, a major feature of tumor malignancy. The role of PLAUR in ccRCC pathology has not been deeply studied. In this study, we collected the mRNA expression data of 33 tumor types, each derived from human patients obtained from TCGA database, and comprehensively analyzed the correlation between the expression of PLAUR in tumors and prognosis. Then, we studied the relationship between PLAUR expression in ccRCC and specific clinical features of ccRCC patients. In addition, we analyzed the function and mechanism of PLAUR in ccRCC. Our results showed that PLAUR was significantly overexpressed in ccRCC and that both PLAUR levels and PLAUR methylation levels significantly correlated with poor prognosis. Our results also suggest that PLAUR is involved in the progression of ccRCC. The results of functional and mechanistic analysis of PLAUR showed that PLAUR is involved in inflammatory and immune-related pathways in ccRCC; other data showed that PLAUR expression may affect the infiltration of multiple immune cell types in ccRCC and that PLAUR levels were significantly and positively correlated with the expression of immune checkpoints. In conclusion, our findings suggest that high PLAUR expression can promote the progression of ccRCC to poor prognosis, and thus PLAUR may serve as both a potential marker for predicting macrophage infiltration and immune microenvironment status and as an important immunotherapy target for ccRCC.

M1 macrophage-derived exosomes and their key molecule lncRNA HOTTIP suppress head and neck squamous cell carcinoma progression by upregulating the TLR5/NF-κB pathway

Exosomes serve as a crucial mode of communication between tumor-associated macrophages (TAMs) and cancer cells. This study attempted to explore the function of M1-derived exosomes and clarify their specific mechanism in head and neck squamous cell carcinoma (HNSCC). Moreover, the functional roles of M1-derived exosomes and their key molecule long noncoding RNA (lncRNA) HOXA transcript at the distal tip (HOTTIP) in HNSCC were investigated by conducting a series of in vitro and in vivo experiments. The dual-luciferase test was utilized to clarify the binding capacities between HOTTIP/mRNA and miRNAs. Accordingly, HOTTIP was found to be upregulated in M1-derived exosomes. Meanwhile, the in vitro experiments indicated that M1 exosomes suppressed proliferation, migration and invasion but induced apoptosis of cancer cells. This function was noted to be enhanced by HOTTIP-overexpressed M1 exosomes but was weakened by HOTTIP-knockdown ones, indicating that HOTTIP serves as a key molecule in M1 exosomes. Therefore, the function of HOTTIP in cancer cells was explored, for which overexpression of HOTTIP was found to inhibit proliferation, migration and invasion but induced apoptosis of cancer cells in vitro. A mechanism study further showed that M1 exosomes and HOTTIP activated the TLR5/NF-κB signaling pathway by competitively sponging miR-19a-3p and miR-19b-3p. Furthermore, cancer cells expressing HOTTIP were noted to induce the polarization of both local M1 and M2 macrophages; however, M1 exosomes were observed to reprogram local TAMs into M1 macrophages. More importantly, both cancer cells expressing HOTTIP and M1 exosomes reeducated circulating monocytes to express the M1 phenotype. The corresponding data demonstrated that the M1 exosomal lncRNA HOTTIP suppresses HNSCC progression by upregulating the TLR5/NF-κB signaling pathway through competitively sponging miR-19a-3p and miR-19b-3p. In particular, M1 exosomes and HOTTIP induce the polarization of M1 in circulating monocytes, thus providing novel insight into HNSCC immunotherapy.

Macrophage C/EBPδ Drives Gemcitabine, but Not 5-FU or Paclitaxel, Resistance of Pancreatic Cancer Cells in a Deoxycytidine-Dependent Manner

Treatment of pancreatic ductal adenocarcinoma (PDAC), a dismal disease with poor survival rates, is hampered by the high prevalence of chemotherapy resistance. Resistance is accompanied by macrophage infiltration into the tumor microenvironment, and infiltrated macrophages are key players in chemotherapy resistance. In the current manuscript, we identify CCAAT/enhancer-binding protein delta (C/EBPδ) as an important transcription factor driving macrophage-dependent gemcitabine resistance. We show that conditioned medium obtained from wild type macrophages largely diminishes gemcitabine-induced cytotoxicity of PDAC cells, whereas conditioned medium obtained from C/EBPδ-deficient macrophages only minimally affects gemcitabine-induced PDAC cell death. Subsequent analysis of RNA-Seq data identified the pyrimidine metabolism pathway amongst the most significant pathways down-regulated in C/EBPδ-deficient macrophages and size filtration experiments indeed showed that the low molecular weight and free metabolite fraction most effectively induced gemcitabine resistance. In line with a role for pyrimidines, we next show that supplementing macrophage conditioned medium with deoxycytidine overruled the effect of macrophage conditioned media on gemcitabine resistance. Consistently, macrophage C/EBPδ-dependent resistance is specific for gemcitabine and does not affect paclitaxel or 5-FU-induced cytotoxicity. Overall, we thus show that C/EBPδ-dependent deoxycytidine biosynthesis in macrophages induces gemcitabine resistance of pancreatic cancer cells.

Role of macrophages in cancer progression and targeted immunotherapies

The vast complexity of the tumor microenvironment (TME) aggrandizes the underlying principles responsible for immune escape, therapy resistance, and treatment failure. The stromal and immune cell population circumjacent to the tumor cells affects the cancer cell cycle leading to tumor progression. Tumor-associated macrophages (TAMs) exhibiting a unique M2 polarization state constitute a significant portion of the TME. They serve as tumor suppressors at early stages and tumor promoters at advanced stages by governing various microenvironmental cues. TAMs secreted various pro-tumoral cytokines, chemokines, and matrix metalloproteases are known to regulate the different cell cycle molecules including checkpoint inhibitors in cancer cells leading to cell cycle progression with faulty cellular components. Moreover, TAMs are well-known immunosuppressors and thereby facilitating the tumor cells' evasion from immune recognition. This chapter will describe the interaction between TAMs and tumor cells, the involvement of TAMs in the regulation of cancer cell progression by controlling cell cycle checkpoints or molecular pathways, and current TAM-based therapies, including restriction of TAM recruitment, anti-survival strategies, or switching polarity. Moreover, this chapter will also emphasize recently developed drug targets and CAR-macrophage cell therapy that restricts tumor progression.

Macrophage-mediated RON signaling supports breast cancer growth and progression through modulation of IL-35

Tumor associated macrophages (TAMs) play a major role in regulating mammary tumor growth and in directing the responses of tumor infiltrating leukocytes in the microenvironment. However, macrophage-specific mechanisms regulating the interactions of macrophages with tumor cells and other leukocytes that support tumor progression have not been extensively studied. In this study, we show that the activation of the RON receptor tyrosine kinase signaling pathway specifically in macrophages supports breast cancer growth and metastasis. Using clinically relevant murine models of breast cancer, we demonstrate that loss of macrophage RON expression results in decreases in mammary tumor cell proliferation, survival, cancer stem cell self-renewal, and metastasis. Macrophage RON signaling modulates these phenotypes via direct effects on the tumor proper and indirectly by regulating leukocyte recruitment including macrophages, T-cells, and B-cells in the mammary tumor microenvironment. We further show that macrophage RON expression regulates the macrophage secretome including IL-35 and other immunosuppressive factors. Overall, our studies implicate activation of RON signaling in macrophages as a key player in supporting a thriving mammary pro-tumor microenvironment through novel mechanisms including the augmentation of tumor cell properties through IL-35.

Association of the Circulating Supar Levels with Inflammation, Fibrinolysis, and Outcome in Severe Burn Patients

BACKGROUND

Hyperfibrinolysis and pro/anti-inflammatory imbalance usually occur in the early stage of severe burns. Soluble urokinase-type plasminogen activator receptor (suPAR) is involved in fibrinolysis and inflammation. To date, the levels of circulating suPAR in non-survivors with severe burns remain unknown. This study aimed to investigate the early association between circulating suPAR levels and biomarkers of fibrinolysis, pro/anti-inflammatory, and prognosis.

METHODS

Sixty-four consecutive Chinese patients with severe burns and 26 healthy volunteers were enrolled in a prospective observational cohort. Clinical characteristics and laboratory data were collected prospectively. Blood samples were collected at 48 h post-burn, and suPAR and biomarkers of pro/anti-inflammatory and fibrinolysis were detected by enzyme-linked immunosorbent assays. Important indicators between non-survivors and survivors were compared. Linear regression analysis was performed to screen variables associated with suPAR. Logistic regression analysis and receiver operating characteristic curve (ROC) analysis were performed to evaluate the prognostic value of suPAR.

RESULT

Compared with the control group, the circulating suPAR levels in the survivors (P < 0.001) and non-survivors (P = 0.017) were higher. Compared with survivors, non-survivors had lower circulating suPAR levels at 48 h post-burn, and they showed a higher degree of fibrinolysis (higher D-dimer) and a lower TNF-α/IL-10 ratio. According to linear regression analysis, the variables independently associated with a lower suPAR level were lower platelet factor 4 (PF-4), urokinase-type plasminogen activator (uPA), and TNF-α/IL-10 levels and a higher D-dimer level. Logistic regression and ROC analyses indicated that a suPAR level ≤ 4.70 μg/L was independently associated with 30-day mortality.

CONCLUSION

Low circulating suPAR levels at 48 h post-burn in severe burn patients may reflect decreased TNF-α/IL-10 ratio and increased hyperfibrinolysis. suPAR can predict 30-day mortality in patients with severe burn.

Evaluation of the immunomodulatory activity of thalidomide on tumor-associated macrophages in the 4T1 murine metastatic breast cancer model

ABSTRACT The present work evaluated the immunomodulatory effect of thalidomide (Thal) at different doses on tumor-associated macrophages (TAMs) using a mouse model of human breast cancer. Mice were inoculated with 4T1 cells in the left flank and treated with Thal once a day at concentrations of 50, 100, and 150mg/kg body weight from the 5th day until the 28th day of tumor inoculation. The tumors were sized, proliferation index and TAMs count were evaluated in primary tumors and metastatic lungs. In addition, the metastasis rate was evaluated in the lungs. Thal at 150mg/kg significantly decreased tumor growth, proliferation index, and TAMs infiltration in primary tumors. Conversely, a higher number of TAMs and lower proliferation index were observed in metastatic lungs in mice treated with 150mg/kg of Thal. Furthermore, Thal at 150mg/kg significantly decreased the metastatic nodules in the lungs. Our findings demonstrated that Thal treatment considerably decreased the primary tumor and lung metastasis in mice associated with different TAM infiltration effects in these sites.

Dysregulated tumor-associated macrophages in carcinogenesis, progression and targeted therapy of gynecological and breast cancers

Gynecological and breast cancers are a group of heterogeneous malignant tumors. Although existing treatment strategies have ameliorated the clinical outcomes of patients, the overall survival rate of advanced diseases remains unsatisfactory. Increasing evidence has indicated that the development and prognosis of tumors are closely related to the tumor microenvironment (TME), which restricts the immune response and provokes malignant progression. Tumor-associated macrophages (TAMs) are the main component of TME and act as a key regulator in tumor metastasis, immunosuppression and therapeutic resistance. Several preclinical trials have studied potential drugs that target TAMs to achieve potent anticancer therapy. This review focuses on the various functions of TAMs and how they influence the carcinogenesis of gynecological and breast cancers through regulating cancer cell proliferation, tumor angiogenesis and tumor-related immunosuppression. Besides, we also discuss the potential application of disabling TAMs signaling as a part of cancer therapeutic strategies, as well as CAR macrophages, TAMs-based vaccines and TAMs nanobiotechnology. These research advances support that targeting TAMs combined with conventional therapy might be used as effective therapeutics for gynecological and breast cancers in the future.

Periostin Exon-21 Antibody Neutralization of Triple-Negative Breast Cancer Cell-Derived Periostin Regulates Tumor-Associated Macrophage Polarization and Angiogenesis

Simple Summary

Despite remarkable advances in breast cancer treatment, few strategies other than standard cytotoxic chemotherapy are available for patients with triple-negative breast cancer (TNBC) due to the lack of therapeutic target molecules. TNBC is still the most aggressive subtype, with a high risk of recurrence and metastasis within 2 years after initial treatment. Thus, there is an unmet medical need to develop new treatments for metastatic and recurrent TNBC patients. In this study we tested a new antibody, targeting extracellular periostin protein alternative splicing variants, which are induced by conventional chemotherapy or during the process of endothelial mesenchymal transition. This antibody reduced periostin-secreting TNBC in a mouse xenograft model, accompanied by a decrease in the number of M2 tumor-associated macrophages and tumor vessels. Periostin alternative splicing variants might be a specific and safe therapeutic target in patients with TNBC.

Abstract

Periostin (Pn) is involved in multiple processes of cancer progression. Previously, we reported that Pn expression is correlated with mesenchymal tumor markers and poor prognosis in triple-negative breast cancer (TNBC). In the TNBC xenograft model, chemotherapy increased expression of a Pn alternative splicing variant (ASV) with exon 21, and administration of the neutralizing antibody against Pn with exon 21 (Pn-21 Ab) overcame chemoresistance with a reduction in the mesenchymal cancer cell fraction. In the present study, the role of Pn ASV with exon 21 in TNBC progression has been addressed. We first established a stable cell line carrying a fluorescence-based splicing reporter. Pn-positive TNBC has higher expression of genes related to tumor-associated macrophage (TAM) recruitment and ECM-receptor interaction than Pn-negative cells. In a xenograft model, only Pn-positive cells initiated tumor formation, and the Pn-21 Ab suppressed tumor cell growth, accompanied by decreased M2 TAM polarization and the number of tumor vessels. These data suggest that cancer cell-derived Pn ASV educates TAMs and regulates angiogenesis, which in turn establishes a microenvironmental niche that is supportive of TNBC.

MicroRNA-200c restoration reveals a cytokine profile to enhance M1 macrophage polarization in breast cancer

Many immune suppressive mechanisms utilized by triple negative breast cancer (TNBC) are regulated by oncogenic epithelial-to-mesenchymal transition (EMT). How TNBC EMT impacts innate immune cells is not fully understood. To determine how TNBC suppresses antitumor macrophages, we used microRNA-200c (miR-200c), a powerful repressor of EMT, to drive mesenchymal-like mouse mammary carcinoma and human TNBC cells toward a more epithelial state. MiR-200c restoration significantly decreased growth of mouse mammary carcinoma Met-1 cells in culture and in vivo. Cytokine profiling of Met-1 and human BT549 cells revealed that miR-200c upregulated cytokines, such as granulocyte-macrophage colony-stimulating factor (GM-CSF), promoted M1 antitumor macrophage polarization. Cytokines upregulated by miR-200c correlated with an epithelial gene signature and M1 macrophage polarization in BC patients and predicted a more favorable overall survival for TNBC patients. Our findings demonstrate that immunogenic cytokines (e.g., GM-CSF) are suppressed in aggressive TNBC, warranting further investigation of cytokine-based therapies to limit disease recurrence.

Plasminogen Activator Urokinase Receptor Implies Immunosuppressive Features and Acts as an Unfavorable Prognostic Biomarker in Glioma

BACKGROUND

Clinical outcomes of patients with glioma are still poor, even after standard treatments, including surgery combined with radiotherapy and chemotherapy. New therapeutic strategies and targets for glioma are urgently needed. Plasminogen activator urokinase receptor (PLAUR), a highly glycosylated integral membrane protein, is reported to modulate plasminogen activation and extracellular matrix degradation in many malignant cancers, but its role in gliomas remains unclear.

METHODS

Glioma samples with mRNA sequencing data and clinical information from the Chinese Glioma Genome Atlas (n = 310) data set and The Cancer Genome Atlas (n = 611) data set were collected for this study. Analyses using Kaplan-Meier plots, time-dependent receiver operating characteristic curves, Cox regression, and nomograms were conducted to evaluate the prognostic performance of PLAUR expression. Analyses using Metascape, ESTIMATE, EPIC, and immunohistochemical staining were performed to reveal the potential biological mechanism. The statistical analysis and graphical work were completed using SPSS, R language, and GraphPad Prism.

RESULTS

PLAUR was highly expressed in phenotypes associated with glioma malignancy and could serve as an independent prognostic indicator. Functional analysis revealed the correlation between PLAUR and immune response. Further studies found that samples with higher PLAUR expression were infiltrated with fewer CD8 T cells and many more M2 macrophages. Strong positive correlation was demonstrated between PLAUR expression and some immunosuppressive markers, including immune checkpoints and cytokines. These findings were also confirmed in patient samples.

CONCLUSION

Our results elucidated the clinical significance and immunosuppressive effect of PLAUR in gliomas, which might provide some clues in glioma immunotherapy.

IMPLICATIONS FOR PRACTICE

Although the efficacy of immunotherapy has been verified in other tumors, its application in glioma is impeded because of the unique microenvironment. Tumor-associated macrophages, which are particularly abundant in a glioma mass, contribute much to the immunosuppressive microenvironment and offer new opportunities in glioma immunotherapy. The results of this study identified plasminogen activator urokinase receptor (PLAUR) expression as a potential marker to predict the infiltration of macrophages and the status of immune microenvironment in patients with glioma, suggesting that treatment decisions could be based on PLAUR level when administering immunotherapeutics. The soluble PLAUR in blood and other body fluids would make this approach easy to implement in the clinic.

Lupus nephritis: correlation of immunohistochemical expression of C4d, CD163-positive M2c-like macrophages and Foxp3-expressing regulatory T cells with disease activity and chronicity

BACKGROUND

C4d, which is a serum complement cleavage product of the activated complement component C4, was found to be an accurate indicator of lupus activity compared to complement levels. Recently, macrophages have been considered to be pivotal members in the pathogenesis of lupus nephritis (LN). M2c-like macrophages have anti-inflammatory functions and promote fibrosis. Multiple studies have detected that LN is associated with an imbalance between the regulatory T cell (Treg) population and the inflammatory T helper subtypes.

METHODS

We evaluated and scored the immunohistochemical expression of C4d, CD163-positive M2C-macrophages and Foxp3-expressing Tregs in 53 renal biopsies of LN. Their expression was scored and correlated with clinical and histological disease activity and chronicity.

RESULTS

Class IV was the most prevalent class (50.9%), followed by class III (17%). PTC-C4d intensity score, CD163% of positive M2c macrophages and FOXP3% of positive Tregs were significantly correlated with chronicity index (r_s = 0.292, p = 0.034; r_s = 0.407, p = 0.003; and r_s = 0.296, p = 0.031, respectively). Also, FOXP3% of positive Tregs was significantly correlated with LN class (r_s = 0.31, p = 0.024).

CONCLUSION

C4d-PTC, CD163-positive M2c macrophages and FOXP3-positive Tregs are markers that significantly correlated with chronicity in LN. Further studies are needed to evaluate their prognostic value.

NR3C2-Related Transcriptome Profile and Clinical Outcome in Invasive Breast Carcinoma

Background

Increasing evidence has indicated that the nuclear receptor subfamily 3 group C member 2 (NR3C2) may be associated with tumorigenesis and patient prognosis for certain types of tumors. However, the clinical significance of NR3C2 is unclear in invasive breast carcinoma (BRCA).

Methods

We used bioinformatics to broadly investigate and obtain a deeper understanding of the prognostic significance between NR3C2 and BRCA. RNA-sequencing data and clinical information of patients with BRCA from the Cancer Genome Atlas database were collected for subsequent analysis. The diagnostic efficacy of NR3C2 was evaluated by calculating the receiver operating characteristic curve. The prognostic value of NR3C2 was evaluated by Kaplan-Meier analysis and Cox regression analysis for patients with BRCA. Moreover, the OSbrca database was used to validate NR3C2 as a prognostic biomarker for BRCA. Gene set enrichment analysis (GSEA) and tumor immune infiltration analysis were conducted to explore the molecular mechanism of NR3C2 in BRCA.

Results

The expression level of NR3C2 in BRCA tissues decreased compared to that in normal breast tissues (P < 0.001). NR3C2 presented good diagnostic efficacy (AUC = 0.908). Moreover, the expression of NR3C2 was verified using the Oncomine database. High expression of NR3C2 was statistically associated with prolonged overall survival (HR = 0.65, 95% CI: 0.47-0.91, and P = 0.012), progression-free interval (HR = 0.68, 95% CI: 0.49-0.95, and P = 0.024), and disease-specific survival (HR = 0.57, 95% CI: 0.36-0.89, and P = 0.015) for patients with BRCA. Besides, the prognostic value of NR3C2 was verified by the OSbrca database. GSEA results suggested that enriched pathways included neuroactive ligand-receptor interaction, focal adhesion, and ECM-receptor interaction. NR3C2 expression was moderately correlated with mast cells and some T cell subsets in BRCA.

Conclusion

NR3C2 is a potential prognostic biomarker that could help clinicians develop more appropriate treatment plans for individual patients with BRCA.

Early macrophage infiltrates impair pancreatic cancer cell growth by TNF-α secretion

Background

Pancreatic ductal adenocarcinoma (PDAC) is a grim disease with high mortality rates. Increased macrophage influx in PDAC is a common hallmark and associated with poor prognosis. Macrophages have high cellular plasticity, which can differentiate into both anti- and pro-tumorigenic properties. Here, we investigated how naïve (M0) macrophages differ from other macrophages in their anti-tumorigenic activities.

Methods

In vitro BrdU proliferation and Annexin V cell death analyses were performed on PANC-1 and MIA PaCa-2 PDAC cell lines exposed to conditioned medium of different macrophage subsets. Macrophage secreted factors were measured by transcript analysis and ELISA. Therapeutic antibodies were used to functionally establish the impact of the identified cytokine on PDAC proliferation.

Results

Proliferation and cell death assays revealed that only M0 macrophages harbor anti-tumorigenic activities and that M1, M2, and TAMs do not. mRNA analysis and ELISA results suggested TNF-α as a potential candidate to mediate M0 macrophage induced cell death. To demonstrate the importance of TNF-α in M0 macrophage-induced cell death, PANC-1 and MIA PaCa-2 cell-lines were exposed to M0 macrophage conditioned medium in the presence of the TNF-α inhibitor Infliximab, which effectively diminished the anti-tumor activities of M0 macrophages.

Conclusion

Newly tumor-infiltrated naive M0 macrophages exert anti-tumorigenic activities via TNF-α secretion. Their subsequent differentiation into either M1, M2, or TAM subsets reduces TNF-α levels, thereby abolishing their cytotoxic activity on PDAC cells. These data suggest that reestablishing TNF-α secretion in differentiated macrophages might yield a therapeutic benefit.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-020-07697-1.

An Innovative Immune Score-Based Prognostic Nomogram for Patients with Cervical Cancer

Background

In the past few years, the immune system and tumor immune microenvironment are becoming increasingly popular as more work has been accomplished in this field. However, nomograms based on immune-related characteristics for prognosis prediction of cervical cancer have not been fully explored to our knowledge. We constructed a novel immune score-based nomogram to predict patients with high risk and poor prognosis.

Materials and Methods

198 patients with cervical cancer from The Cancer Genome Atlas (TCGA) database were included in our study. Immune scores were generated with Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data (ESTIMATE) algorithm, and clinic-pathological characteristics were also included for subsequent analysis. Cox proportional hazards regression models were performed for univariate and multivariate analyses to screen the significant factors, and a prognostic nomogram was built. Bootstrap resampling analysis was used for internal validation. The calibration curve and concordance index (C-index) were used to assess the predictive performance of the nomogram.

Results

Patients were split into three subgroups based on immune scores. We found that patients with high immune scores conferred significantly better overall survival (OS) compared with those with medium and low immune scores (hazard ratio (HR), 0.305; 95% confidence interval (CI), 0.108-0.869). A nomogram with a C-index of 0.720 had a favorable performance for predicting survival rate for clinical use by combining immune scores with other clinical features. The calibration curves at 3 and 5 years suggested a good consistency between the predicted OS and the actual OS probability.

Conclusions

Our work highlights the potential clinical application significance of immune score-based nomogram in predicting the OS of cervical cancer patients.

Stromal CCL2 Signaling Promotes Mammary Tumor Fibrosis through Recruitment of Myeloid-Lineage Cells

Obesity is correlated with breast tumor desmoplasia, leading to diminished chemotherapy response and disease-free survival. Obesity causes chronic, macrophage-driven inflammation within breast tissue, initiated by chemokine ligand 2 (CCL2) signaling from adipose stromal cells. To understand how CCL2-induced inflammation alters breast tumor pathology, we transplanted oncogenically transformed human breast epithelial cells with breast stromal cells expressing CCL2 or empty vector into murine mammary glands and examined tumor formation and progression with time. As tumors developed, macrophages were rapidly recruited, followed by the emergence of cancer-associated fibroblasts (CAFs) and collagen deposition. Depletion of CD11b + myeloid lineage cells early in tumor formation reduced tumor growth, CAF numbers, and collagen deposition. CCL2 expression within developing tumors also enhanced recruitment of myeloid progenitor cells from the bone marrow into the tumor site. The myeloid progenitor cell population contained elevated numbers of fibrocytes, which exhibited platelet-derived growth factor receptor-alpha (PDGFRα)-dependent colony formation and growth in vitro. Together, these results suggest that chronic inflammation induced by CCL2 significantly enhances tumor growth and promotes the formation of a desmoplastic stroma through early recruitment of macrophages and fibrocytes into the tumor microenvironment. Fibrocytes may be a novel target in the tumor microenvironment to reduce tumor fibrosis and enhance treatment responses for obese breast cancer patients.

Clinicopathologic Characteristics of Breast Cancer According to the Infiltrating Immune Cell Subtypes

The clinical significance of immune cell subtypes in breast cancer remains poorly understood. To identify tumor-infiltrating immune cell subtypes in breast cancer and investigate their implications, tissue microarrays were constructed using 334 cases of invasive ductal carcinoma (luminal A type: 162 (48.5%), luminal B type: 96 (28.7%), HER-2 type: 21 (6.3%), and triple negative breast cancer: 55 (16.5%)). Hormone receptors (ER, PR, and HER-2), Ki-67, and immune cell subtype-related proteins (STAT4, STAT6, FOXP3, CD8, CD68, and CD163) were assessed immunohistochemically. The proportion of highly expressed STAT6, FOXP3, CD8, CD68, and CD163 proteins was found to be lowest in luminal A type but highest in the HER-2 type. Additionally, high-level STAT6, FOXP3, CD68, and CD163 protein expression was associated with higher histologic grade. ER negativity was associated with high STAT6, FOXP3, and CD163 expression levels, whereas PR negativity and high Ki-67 labeling index were associated with high CD163 expression. Univariate (p = 0.003) and multivariate Cox (hazard ratio: 2.435, 95% CI: 1.110-5.344, p = 0.049) analyses showed that high CD8 expression is an independent factor associated with shorter disease-free survival. Immune cell subtype-related protein expression is dependent on breast cancer molecular subtypes, and CD8 expression is associated with patient prognosis.

Gene expression profiling of tumor stroma interactions in retinoblastoma

We aimed to identify the critical molecular pathways altered upon tumor stroma interactions in retinoblastoma (RB). In vitro 2 D cocultures of RB tumor cells (Weri-Rb-1 and NCC-RbC-51) with primary bone marrow stromal cells (BMSC) was established. Global gene expression patterns in coculture samples were assessed using Affymetrix Prime view human gene chip microarray and followed with bioinformatics analyses. Key upregulated genes from Weri-Rb-1 + BMSC and NCC-RbC-51 + BMSC coculture were validated using qRT-PCR to ascertain their role in RB progression. Whole genome microarray experiments identified significant (P ≤ 0.05, 1.1 log 2 FC) transcriptome level changes induced upon coculture of RB cells with BMSC. A total of 1155 genes were downregulated and 1083 upregulated in Weri-Rb-1 + BMSC coculture. Similarly, 1865 genes showed downregulation and 1644 genes were upregulation in NCC-RbC-51 + BMSC coculture. The upregulated genes were significantly associated with pathways of focal adhesion, PI3K-Akt signalling, ECM-receptor interaction, JAK-STAT, TGF-β signalling thus contributing to RB progression. Validation of key genes by qRT-PCR revealed significant overexpression of IL8, IL6, MYC and SMAD3 in the case of Weri-Rb-1 + BMSC coculture and IL6 in the case of NCC-RbC-51 + BMSC coculture. The microarray expression study on in vitro RB coculture models revealed the pathways that could be involved in the progression of RB. The gene signature obtained in a stimulated model when a growing tumor interacts with its microenvironment may provide new horizons for potential targeted therapy in RB.

Caveolin-1 in oncogenic metabolic symbiosis

Metabolic phenotypes of cancer cells are heterogeneous and flexible as a tumor mass is a hurriedly evolving system capable of constant adaptation to oxygen and nutrient availability. The exact type of cancer metabolism arises from the combined effects of factors intrinsic to the cancer cells and factors proposed by the tumor microenvironment. As a result, a condition termed oncogenic metabolic symbiosis in which components of the tumor microenvironment (TME) promote tumor growth often occurs. Understanding how oncogenic metabolic symbiosis emerges and evolves is crucial for perceiving tumorigenesis. The process by which tumor cells reprogram their TME involves many mechanisms, including changes in intercellular communication, alterations in metabolic phenotypes of TME cells, and rearrangement of the extracellular matrix. It is possible that one molecule with a pleiotropic effect such as Caveolin-1 may affect many of these pathways. Here, we discuss the significance of Caveolin-1 in establishing metabolic symbiosis in TME.

Inflammatory macrophage derived TNFα downregulates estrogen receptor α via FOXO3a inactivation in human breast cancer cells

Patients with estrogen receptor α positive (ERα⁺) breast cancer can respond to endocrine therapy, but treatment resistance is common and associated with downregulation of ERα expression in the dormant residual cells. Here we show, using long-term NSG xenograft models of human breast cancer and primary human monocytes, in vitro primary cell cultures and tumors from breast cancer patients, that macrophage derived tumor necrosis factor alpha (TNFα) downregulates ERα in breast cancer cells via inactivation of the transcription factor Forkhead box O transcription factor 3a (FOXO3a). Moreover, presence of tumor associated macrophages in the primary tumor of breast cancer patients, was associated with ERα negativity, and with worse prognosis in patients with ERα⁺ tumors. We propose that pro-inflammatory macrophages, despite being tumoricidal, may have direct effects on tumor progression and endocrine resistance in breast cancer patients. Our findings suggest that TNFα antagonists should be evaluated for treatment of ERα⁺ breast cancer.

Macrophage-secreted MMP9 induces mesenchymal transition in pancreatic cancer cells via PAR1 activation

PURPOSE

Targeting tumor-infiltrating macrophages limits progression and improves chemotherapeutic responses in pancreatic ductal adenocarcinoma (PDAC). Protease-activated receptor (PAR)1 drives monocyte/macrophage recruitment, and stromal ablation of PAR1 limits cancer growth and enhances gemcitabine sensitivity in experimental PDAC. However, the functional interplay between PAR1, macrophages and tumor cells remains unexplored. Here we address the PAR1-macrophage-tumor cell crosstalk and assess its contributions to tumor progression.

METHODS

PAR1 expression and macrophage infiltration were correlated in primary PDAC biopsies using gene expression datasets and tissue microarrays. Medium transfer experiments were used to evaluate the functional consequences of macrophage-tumor cell crosstalk and to assess the contribution of PAR1 to the observed responses. PAR1 cleavage assays were used to identify a macrophage-secreted PAR1 agonist, and the effects of candidate proteases were assessed in medium transfer experiments with specific inhibitors and/or recombinant agonist.

RESULTS

PAR1 expression correlates with macrophage infiltration in primary PDACs, and macrophages induce mesenchymal transition of PDAC cells through PAR1 activation. Protease profiling identified macrophage-secreted matrix metalloprotease 9 (MMP9) as the relevant PAR1 agonist in PDAC. PAR1 and/or MMP9 inhibition limited macrophage-driven mesenchymal transition. Likewise, preventing mesenchymal transition by silencing ZEB1 or by pharmacological inhibition of the MMP9/PAR1 axis significantly reduced the ability of tumor cells to survive the anti-tumor activities of macrophages.

CONCLUSION

Macrophages secrete MMP9, which acts upon PDAC cell PAR1 to induce mesenchymal transition. This macrophage-induced mesenchymal transition supports the tumor-promoting role of macrophage influx, explaining the dichotomous contributions of these immune cells to tumor growth.

Tumor-associated macrophages: an accomplice in solid tumor progression

In many solid tumor types, tumor-associated macrophages (TAMs) are important components of the tumor microenvironment (TME). Moreover, TAMs infiltration is strongly associated with poor survival in solid tumor patients. In this review, we describe the origins of TAMs and their polarization state dictated by the TME. We also specifically focus on the role of TAMs in promoting tumor growth, enhancing cancer cells resistance to chemotherapy and radiotherapy, promoting tumor angiogenesis, inducing tumor migration and invasion and metastasis, activating immunosuppression. In addition, we discuss TAMs can be used as therapeutic targets of solid tumor in clinics. The therapeutic strategies include clearing macrophages and inhibiting the activation of TAMs, promoting macrophage phagocytic activity, limiting monocyte recruitment and other targeted TAMs therapies.

Differences in intra-tumoral macrophage infiltration and radiotherapy response among intrinsic subtypes in pT1-T2 breast cancers treated with breast-conserving surgery

Breast cancer (BC) intrinsic subtype classification is based on the expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and proliferation marker Ki-67. The expression of these markers depends on both the genetic background of the cancer cells and the surrounding tumor microenvironment. In this study, we explore macrophage traits in cancer cells and intra-tumoral M2-macrophage infiltration (MI) in relation to intrinsic subtypes in non-metastatic invasive BC treated with breast conserving surgery, with and without postoperative radiotherapy (RT). Immunostaining of M2-macrophage-specific antigen CD163 in cancer cells and MI were evaluated, together with ER, PR, HER2, and Ki-67-expression in cancer cells. The tumors were classified into intrinsic subtypes according to the ESMO guidelines. The immunostaining of these markers, MI, and clinical data were analyzed in relation to ipsilateral local recurrence (ILR) as well as recurrence-free (RFS) and disease-free specific (DFS) survival. BC intrinsic subtypes are associated with T-stage, Nottingham Histologic Grade (NHG), and MI. Macrophage phenotype in cancer cells is significantly associated with NHG3-tumors. Significant differences in macrophage infiltration were observed among the intrinsic subtypes of pT1-T2 stage BC. Shorter RFS was observed in luminal B HER2neg tumors after RT, suggesting that this phenotype may be more resistant to irradiation. Ki-67-expression was significantly higher in NHG3 and CD163-positive tumors, as well as those with moderate and high MI. Cancer cell ER expression is inversely related to MI and thus might affect the clinical staging and assessment of BC.

Exploiting vulnerabilities of cancer by targeting nuclear receptors of stromal cells in tumor microenvironment

The tumor microenvironment is a complex and dynamic cellular community comprising the tumor epithelium and various tumor-supporting cells such as immune cells, fibroblasts, immunosuppressive cells, adipose cells, endothelial cells, and pericytes. The interplay between the tumor microenvironment and tumor cells represents a key contributor to immune evasiveness, physiological hardiness and the local and systemic invasiveness of malignant cells. Nuclear receptors are master regulators of physiological processes and are known to play pro-/anti-oncogenic activities in tumor cells. However, the actions of nuclear receptors in tumor-supporting cells have not been widely studied. Given the excellent druggability and extensive regulatory effects of nuclear receptors, understanding their biological functionality in the tumor microenvironment is of utmost importance. Therefore, the present review aims to summarize recent evidence about the roles of nuclear receptors in tumor-supporting cells and their implications for malignant processes such as tumor proliferation, evasion of immune surveillance, angiogenesis, chemotherapeutic resistance, and metastasis. Based on findings derived mostly from cell culture studies and a few in vivo animal cancer models, the functions of VDR, PPARs, AR, ER and GR in tumor-supporting cells are relatively well-characterized. Evidence for other receptors, such as RARβ, RORγ, and FXR, is limited yet promising. Hence, the nuclear receptor signature in the tumor microenvironment may harbor prognostic value. The clinical prospects of a tumor microenvironment-oriented cancer therapy exploiting the nuclear receptors in different tumor-supporting cells are also encouraging. The major challenge, however, lies in the ability to develop a highly specific drug delivery system to facilitate precision medicine in cancer therapy.

Tumor-Associated Macrophages as Potential Prognostic Biomarkers of Invasive Breast Cancer

Purpose

Tumor-associated macrophages (TAMs) are activated macrophages associated with tumor progression in various cancers. TAMs can polarize M1 or M2 type. M1 has a pro-inflammatory function and kills pathogens. Conversely, M2 shows immunosuppressive action and promotes tumor growth. There are various markers of TAMs. CD11c is considered as a specific marker of M1. CD163 is an optimal marker for M2. CD68 is known as a pan-macrophage marker. We evaluated the relationship between the clinicopathological parameters and immunohistochemical expressions of CD11c, CD163, and CD68 in invasive breast cancer (IBC), and the prognostic value of macrophage localization within the tumor stroma (TS) and tumor nest (TN).

Methods

Immunohistochemistry of CD68, CD11c, and CD163 was analyzed on tissue microarrays of 367 IBCs. The number of CD68+, CD11c+, or CD163+ macrophages in TN vs. TS was counted by 2 pathologists. The correlations between the degree of macrophage (CD68+, CD11c+, or CD163+) infiltration and the clinicopathological parameters were analyzed. We also assessed the impact of macrophages (CD68+, CD11c+, or CD163+) on disease free survival (DFS) and overall survival (OS).

Results

High numbers of macrophages (CD68+, CD11c+, or CD163+) were associated with higher histologic grade, higher Ki-67 proliferating index, estrogen receptor negativity, and progesterone receptor negativity. High numbers of macrophages (CD11c+ or CD163+) in TS were associated with a larger tumor size. Furthermore, CD163+ macrophages in TN were an independent prognostic marker of reduced OS and DFS. Conversely, CD11c+ macrophages in TS were an independent prognostic marker for higher OS and DFS.

Conclusion

TAMs, including M2 type, are associated with tumor progression in IBC. They can also act as a significant unfavorable or favorable prognostic factor. In addition to simply analyzing the degree of TAM infiltration, it is also important to analyze the location of TAMs.

Can tumor-associated macrophages in ductal carcinoma in situ on biopsy predict invasive carcinoma on excision?

Recent trials have explored surveillance of ductal carcinoma in situ (DCIS) without complete excision, but it is difficult to fully exclude an associated, unsampled invasive focus. Tumor microenvironment, including tumor-associated macrophages, may play a role in the transition from in situ to invasive carcinoma, and the presence of CD163-positive cells with DCIS has been associated with increased risk of progression to invasive carcinoma. We aimed to evaluate the role of DCIS-associated CD163-positive cells on biopsy in predicting associated invasion on excision. Immunohistochemistry for CD163 was performed on 57 total biopsy cases of DCIS of low (n = 13), intermediate (n = 21), and high (n = 23) nuclear grade, 27 (47%) of which showed invasion on the subsequent excision specimen. Positive intratumoral and stromal cells were quantified independently by 2 observers based on the percentage of cells staining. Intratumoral CD163 scores ranged from 0 to 2 (mean, 0.7). Stromal CD163 scores ranged from 0 to 3 (mean, 1.3). Intratumoral and stromal CD163 levels were not significantly associated with the presence of subsequent invasion when evaluated as a whole group (P = .36 and P = .47) or when subdivided into low (P = .36 and P = .17), intermediate (P = .82 and P = .82), or high (P = .09 and P = .68) nuclear grades. There was no correlation between intratumoral CD163 content and DCIS grade (P = .257). A trend for higher stromal CD163 expression was seen with higher-grade DCIS, although not statistically significant (P = .178). In conclusion, CD163 on breast core biopsy does not help select patients who may safely forgo excision of DCIS.

Dynamic evaluation of the immune infiltrate and immune function genes as predictive markers for neoadjuvant chemotherapy in hormone receptor positive, HER2 negative breast cancer

Gene expression (GE) signatures and Tumor Infiltrating Lymphocytes (TIL) enumeration are predictive for response to neoadjuvant chemotherapy in HR- and in HER2+ breast cancer, but data are conflicting in HR+/HER2- disease. This study aimed to explore their predictive value in this subset, measured both at baseline and after short exposure to chemotherapy. Specifically, the PROMIX phase 2 trial enrolled patients with locally advanced HER2- BC to receive six cycles of epirubicin and docetaxel, plus bevacizumab during cycles 3-6. Patients underwent tumor biopsies at baseline and after cycle 2 for GE profiling and enumeration of TIL, FOXP3+ T-cells and CD163+ macrophages. An immune related gene module and the quantification of the immune infiltrate were analyzed for association with pathologic complete response (pCR), decrease in tumor size and disease-free survival (DFS). Of the 150 patients enrolled in PROMIX, 113 were HR+/HER2-. Baseline GE and immune cell enumeration data were available from 71 patients, while data after 2 cycles of chemotherapy were available from 41. At baseline, only GE was statistically significantly associated with higher pCR rates (OR 2.29, 95% CI 1.05 - 5.38, p = 0.037) and decrease in tumor size (r = 0.25, p = 0.047). In contrast, longitudinal data indicate that both GE (r = 0.54, p<0.001) and TIL abundance (p = 0.009) are stronger predictors for the reduction of tumor size, while low FOXP3+ was statistically significantly associated with an improved DFS (p = 0.027). In conclusion, GE analysis, TIL and FOXP3+ enumeration after short-term exposure to chemotherapy carry important predictive information in HR+/HER2- breast cancer at the neoadjuvant setting.

Pathological significance and prognostic roles of densities of CD57+ cells, CD68+ cells, and mast cells, and their ratios in clear cell renal cell carcinoma

The immune system is closely associated with malignant behavior in renal cell carcinoma (RCC). Therefore, understanding the pathological roles of immune cells in tumor stroma is essential to discuss the pathological characteristics of RCC. In this study, the clinical significance of densities of CD57+ cells, CD68+ cells, and mast cells, and their ratios were investigated in patients with clear cell RCC. The densities of CD57+, CD68+, and mast cells were evaluated by immunohistochemical techniques in 179 patients. Proliferation index, apoptotic index, and microvessel density were evaluated by using anti-Ki-67, anti-cleaved caspase-3, and anti-CD31 antibodies, respectively. The density of CD57+ cell was negatively correlated with grade, pT stage, and metastasis, although densities of CD68+ cell and mast cell were positively correlated. Ratios of CD68+ cell/CD57+ cell and mast cell/CD57+ cell were significantly correlated with grade, pT stage, and metastasis. Survival analyses showed that the CD68+ cell/CD57+ cell ratio was a significant predictor for cause-specific survival by multivariate analyses (hazard ratio = 1.41, 95% confidence interval = 1.03-1.93, P = .031) and was significantly correlated with proliferation index, apoptotic index, and microvessel density (r = .47, P <. 001; r = -.31, P < .001; and r = .40, P < .001, respectively). In conclusion, CD57+ cells, CD68+ cells, and mast cells played important roles in malignancy in clear cell RCC. The CD68+ cell/CD57+ cell ratio was strongly correlated with pathological features and prognosis in these patients because this ratio reflected the status of cancer cell proliferation, apoptosis, and angiogenesis.

Tumor-associated macrophages and crown-like structures in adipose tissue in breast cancer

PURPOSE

We aimed to evaluate macrophage infiltration and to identify the status of crown-like structures (CLSs) in mammary adipose tissue of human breast tissue in cases with and without breast cancer.

METHODS

Breast adipose tissue was obtained from reduction mammoplasty (N = 56, Group 1), non-neoplastic breast tissue of breast cancer patients (N = 84, Group 2), and breast cancer with adipose stroma (N = 140, Group 3). Immunohistochemical staining of CD68 and CD163 was performed, and the infiltrating macrophages and CLSs within breast adipose tissue were evaluated.

RESULTS

Group 3 had the largest number of CD68-positive (CD68⁺) and CD163-positive (CD163⁺) macrophages and CLSs within adipose tissue (P < 0.001). Among Group 3, cases with high levels of CD68⁺ and CD163⁺ macrophages commonly had a higher histologic grade (P = 0.016 and P = 0.045), and cases with CD163⁺ CLSs were correlated with old age (P = 0.042), estrogen receptor negativity (P = 0.013), human epidermal growth factor receptor-2 positivity (P = 0.043), and non-luminal A type (P = 0.039). Upon univariate analysis, high levels of CD163⁺ macrophages were associated with shorter disease-free survival in node-negative breast cancer patients (P = 0.033), and CD68⁺ CLSs were associated with shorter overall survival in node-positive breast cancer patients (P = 0.015).

CONCLUSIONS

CD68⁺ and/or CD163⁺ tumor-associated macrophage infiltration as well as CLSs are present in adipose tissue nearby the breast cancer lesion, and are associated with various clinicopathologic parameters of breast cancer.