Serum macrophage-colony stimulating factor levels in colorectal cancer patients correlate with lymph node metastasis and poor prognosis

Reciprocal Modulation of Tumour and Immune Cell Motility: Uncovering Dynamic Interplays and Therapeutic Approaches

Dysregulated cell movement is a hallmark of cancer progression and metastasis, the leading cause of cancer-related mortality. The metastatic cascade involves tumour cell migration, invasion, intravasation, dissemination, and colonisation of distant organs. These processes are influenced by reciprocal interactions between cancer cells and the tumour microenvironment (TME), including immune cells, stromal components, and extracellular matrix proteins. The epithelial-mesenchymal transition (EMT) plays a crucial role in providing cancer cells with invasive and stem-like properties, promoting dissemination and resistance to apoptosis. Conversely, the mesenchymal-epithelial transition (MET) facilitates metastatic colonisation and tumour re-initiation. Immune cells within the TME contribute to either anti-tumour response or immune evasion. These cells secrete cytokines, chemokines, and growth factors that shape the immune landscape and influence responses to immunotherapy. Notably, immune checkpoint blockade (ICB) has transformed cancer treatment, yet its efficacy is often dictated by the immune composition of the tumour site. Elucidating the molecular cross-talk between immune and cancer cells, identifying predictive biomarkers for ICB response, and developing strategies to convert cold tumours into immune-active environments is critical to overcoming resistance to immunotherapy and improving patient survival.

Macrophages in tumor cell migration and metastasis

Tumor-associated macrophages (TAMs) are a phenotypically diverse, highly plastic population of cells in the tumor microenvironment (TME) that have long been known to promote cancer progression. In this review, we summarize TAM ontogeny and polarization, and then explore how TAMs enhance tumor cell migration through the TME, thus facilitating metastasis. We also discuss how chemotherapy and host factors including diet, obesity, and race, impact TAM phenotype and cancer progression. In brief, TAMs induce epithelial-mesenchymal transition (EMT) in tumor cells, giving them a migratory phenotype. They promote extracellular matrix (ECM) remodeling, allowing tumor cells to migrate more easily. TAMs also provide chemotactic signals that promote tumor cell directional migration towards blood vessels, and then participate in the signaling cascade at the blood vessel that allows tumor cells to intravasate and disseminate throughout the body. Furthermore, while chemotherapy can repolarize TAMs to induce an anti-tumor response, these cytotoxic drugs can also lead to macrophage-mediated tumor relapse and metastasis. Patient response to chemotherapy may be dependent on patient-specific factors such as diet, obesity, and race, as these factors have been shown to alter macrophage phenotype and affect cancer-related outcomes. More research on how chemotherapy and patient-specific factors impact TAMs and cancer progression is needed to refine treatment strategies for cancer patients.

Monocyte and Macrophage Functions in Oncogenic Viral Infections

Monocytes and macrophages are part of innate immunity and constitute the first line of defense against pathogens. Bone marrow-derived monocytes circulate in the bloodstream for one to three days and then typically migrate into tissues, where they differentiate into macrophages. Circulatory monocytes represent 5% of the nucleated cells in normal adult blood. Following differentiation, macrophages are distributed into various tissues and organs to take residence and maintain body homeostasis. Emerging evidence has highlighted the critical role of monocytes/macrophages in oncogenic viral infections, mainly their crucial functions in viral persistence and disease progression. These findings open opportunities to target innate immunity in the context of oncogenic viruses and to explore their potential as immunotherapies.

The prognostic role of lymphocyte-to-monocyte ratio in patients with resectable pancreatic cancer: a systematic review and meta-analysis

Objectives

This systematic review and meta-analysis examined whether the lymphocyte-to-monocyte ratio (LMR) can serve as an indicator for predicting the prognosis of patients with resectable pancreatic cancer.

Patients and Methods

This meta-analysis was registered with PROSPERO: CRD42023461260. A systematic literature search was conducted in the PubMed, Embase, Cochrane, and Web of Science databases up to September 2023 to assess whether LMR can predict the prognosis of patients with resectable pancreatic cancer. The outcomes measured included subgroup analyses of overall survival (OS) with hazard ratios (HR) and confidence intervals of geographical region, patient population, and LMR threshold. A sensitivity analysis was also performed for OS and HR and confidence intervals were calculated for recurrence-free survival (RFS).

Results

A total of 14 eligible articles, comprising 4,019 patients, were included in the comprehensive analysis. The results of this comprehensive analysis indicate that LMR is a robust predictor of OS, demonstrating strong prognostic significance (HR = 0.55, 95% CI [0.44-0.69], I2 = 79%, P < 0.00001). This predictive significance extended to various types of pancreatic cancer, such as pancreatic ductal adenocarcinoma (HR = 0.73, 95% CI [0.57-0.93], I2 = 46%, P = 0.01), pancreatic neuroendocrine neoplasms (HR = 0.81, 95% CI [0.66-0.99], P = 0.04) and other subtypes (HR = 0.40, 95% CI [0.22-0.72], I2 = 89%, P < 0.00001), but not to pancreatic head cancer (HR = 0.46, 95% CI [0.16-1.13], I2 = 59%, P = 0.12). LMR retained its predictive value across different regions, including Asia (HR = 0.62, 95% CI [0.47-0.76], I2 = 68%, P < 0.0001), Europe (HR = 0.78, 95% CI [0.67-0.91], I2 = 0%, P = 0.002), and the Americas (HR = 0.14, 95% CI [0.08-0.24], I2 = 0%, P < 0.00001). Notably, both LMR cut-off values greater than or equal to three (HR = 0.62, 95% CI [0.47-0.82], I2 = 67%, P = 0.0009) and less than three (HR = 0.47, 95% CI [0.32-0.69], I2 = 85%, P = 0.0001) exhibited prognostic significance. The sensitivity analysis for OS confirmed the strong predictive value of LMR, whereas LMR did not exhibit predictive significance for RFS (HR = 0.35, 95% CI [0.09-1.32], I2 = 95%, P = 0.12). In both subgroups categorized by Newcastle-Ottawa Scale (NOS) scores of ≥7 (HR = 0.66, 95% CI [0.54-0.80], I2 = 53%, P = 0.04) and <7 (HR = 0.41, CI [0.23-0.72], I2 = 89%, P < 0.00001), LMR was demonstrated to have predictive value.

Conclusion

Despite the observed heterogeneity and potential biases in the included studies, the findings of this study suggest that LMR may serve as a valuable predictor of OS in patients with resectable pancreatic cancer.

Blockade of tumor-derived colony-stimulating factor 1 (CSF1) promotes an immune-permissive tumor microenvironment

The macrophage colony-stimulating factor 1 (CSF1) is a chemokine essential for the survival, proliferation, and differentiation of mononuclear phagocytes from hemopoietic stem cells. In addition to its essential physiological role in normal tissues, the CSF1/CSF1 receptor axis is known to be overexpressed in many tumor types and associated with poor prognosis. High levels of CSF1 within the tumor microenvironment have been shown to recruit and reeducate macrophages to produce factors that promote tumor invasiveness and accelerate metastasis. In this study, we demonstrate, for the first time, that treating established syngeneic murine colon and breast carcinoma tumors with a CSF1R-blocking antibody also promotes the expansion of neoepitope-specific T cells. To assess the role of tumor-derived CSF1 in these model systems, we generated and characterized CSF1 CRISPR-Cas9 knockouts. Eliminating tumor-derived CSF1 results in decreased tumor growth and enhanced immunity against tumor-associated neoepitopes, potentially promoting an immune permissive tumor microenvironment in tumor-bearing mice. The combination of neoepitope vaccine with anti-PDL1 in the MC38 CSF1-/- tumor model significantly decreased tumor growth in vivo. Moreover, anti-CSF1R therapy combined with the adeno-TWIST1 vaccine resulted in tumor control, decreased metastasis, and a synergistic increase in CD8 T cell infiltration in 4T1 mammary tumors. Analysis of the tumor microenvironment demonstrated greater CD8 T cell infiltration and a reduction in tumor-associated macrophages following CSF1R inhibition in both tumor models. Our findings thus add to the therapeutic potential of CSF1 targeting agents by employing combinations with vaccines to modulate anti-neoepitope responses in the tumor microenvironment.

A phase I/II study of LY3022855 with BRAF/MEK inhibition in patients with Melanoma

BRAF/MEK targeted therapies and immune checkpoint inhibition have dramatically improved disease control and survival of patients with advanced melanoma. However, most patients do not have durable benefit from either of these therapies. BRAF targeted therapy often has a limited duration of efficacy due to the development of resistance. Pre-clinical data suggest that one possible way to overcome resistance to BRAF/MEK targeted therapy may be the addition of CSF1R inhibition. In this phase I/II study we evaluated the safety and efficacy of LY3022855, an anti-colony stimulating factor-1 receptor (CSF-1R) monoclonal antibody in combination with the BRAF inhibitor vemurafenib and the MEK inhibitor cobimetinib in patients with BRAF V600E/K mutant metastatic melanoma. The trial was terminated early due to discontinuation of the development program for LY3022855 by the sponsor. Between August 2017 and May 2018 five pts were enrolled. Three patients experienced grade 3 events that were deemed possibly related to LY3022855. There were no grade 4 or grade 5 events related to LY3022855. One of the 5 patients had a complete response (CR), whereas the other 4 had progressive disease (PD). Median progression free survival was 3.9 months (90% CI: 1.9-37.2 mos). CSF1R inhibition with LY3022855 in combination with BRAF/MEK inhibition with vemurafenib and cobimetinib was difficult to tolerate in a small melanoma population. One response was observed in this small sample of patients suggesting this combination might be worthy of further exploration.

A phase I/II study of MCS110 with BRAF/MEK inhibition in patients with melanoma after progression on BRAF/MEK inhibition

BACKGROUND

Prognosis for patients with metastatic melanoma has been improved dramatically with the development of BRAF/MEK directed therapy and immune checkpoint inhibition. However, resistance to therapy remains a challenge, particularly with BRAF/MEK targeted therapy which often has a limited duration of efficacy. Pre-clinical data suggest that adding CSF1 inhibition to BRAF/MEK targeted therapy may reduce resistance and increase efficacy.

METHODS

We performed a phase I/II study to determine the safety and efficacy of CSF1 inhibition with MCS110 in combination with BRAF/MEK inhibition with dabrafenib/trametinib in patients with BRAF V600E/K mutant metastatic melanoma. The trial was terminated early due to a decision by the study sponsor to cease further development of MCS110.

RESULTS

Between September 2018 to July 2019 six patients were enrolled on the study. Patients were evenly split between female (50%) and male (50%) with a median age of 59.5 yrs. (26-71). Five patients experienced grade 3 toxicities that were possibly related to one of the therapies, there were no grade 4 or grade 5 events. One patient had a partial response (PR) by RECIST 1.1, one patient had stable disease (SD), 3 patients had disease progression (PD). Median progression free survival was 2.3 months (90% CI: 1.3 mos to not reached).

CONCLUSION

MCS110 in combination with dabrafenib and trametinib was reasonably well tolerated in a small melanoma population. One response was observed in this small sample of patients suggesting this combination might be worthy of further exploration.

The Role of Tumor Epithelial-Mesenchymal Transition and Macrophage Crosstalk in Cancer Progression

PURPOSE OF REVIEW

The purpose of this review is to summarize the recently published findings regarding the role of epithelial to mesenchymal transition (EMT) in tumor progression, macrophages in the tumor microenvironment, and crosstalk that exists between tumor cells and macrophages.

RECENT FINDINGS

EMT is a crucial process in tumor progression. In association with EMT changes, macrophage infiltration of tumors occurs frequently. A large body of evidence demonstrates that various mechanisms of crosstalk exist between macrophages and tumor cells that have undergone EMT resulting in a vicious cycle that promotes tumor invasion and metastasis. Tumor-associated macrophages and tumor cells undergoing EMT provide reciprocal crosstalk which leads to tumor progression. These interactions provide potential targets to exploit for therapy.

Tumor-associated macrophages employ immunoediting mechanisms in colorectal tumor progression: Current research in Macrophage repolarization immunotherapy

Tumor-associated macrophages (TAMs) constitute the most prolific resident of the tumor microenvironment (TME) that regulate its TME into tumor suppressive or progressive milieu by utilizing immunoediting machinery. Here, the tumor cells construct an immunosuppressive microenvironment that educates TAMs to polarize from anti-tumor TAM-M1 to pro-tumor TAM-M2 phenotype consequently contributing to tumor progression. In colorectal cancer (CRC), the TME displays a prominent pro-tumorigenic immune profile with elevated expression of immune-checkpoint molecules notably PD-1, CTLA4, etc., in both MSI and ultra-mutated MSS tumors. This authenticated immune-checkpoint inhibition (ICI) immunotherapy as a pre-requisite for clinical benefit in CRC. However, in response to ICI, specifically, the MSI^hi tumors evolved to produce novel immune escape variants thus undermining ICI. Lately, TAM-directed therapies extending from macrophage depletion to repolarization have enabled TME alteration. While TAM accrual implicates clinical benefit in CRC, sustained inflammatory insult may program TAMs to shift from M1 to M2 phenotype. Their ability to oscillate on both facets of the spectrum represents macrophage repolarization immunotherapy as an effective approach to treating CRC. In this review, we briefly discuss the differentiation heterogeneity of colonic macrophages that partake in macrophage-directed immunoediting mechanisms in CRC progression and its employment in macrophage re-polarization immunotherapy.

Cross Talk Between Macrophages and Cancer Cells in the Bone Metastatic Environment

The skeleton is a common site for cancer metastases with the bone microenvironment providing the appropriate conditions for cancer cell colonization. Once in bone, cancer cells effectively manipulate their microenvironment to support their growth and survival. Despite previous efforts to improve treatment modalities, skeletal metastases remain with poor prognoses. This warrants an improved understanding of the mechanisms leading to bone metastasis that will aid development of effective treatments. Macrophages in the tumor microenvironment are termed tumor associated macrophages (TAMs) and their crosstalk with cancer cells is critical in regulating tumorigenicity in multiple cancers. In bone metastases, this crosstalk is also being increasingly implicated but the specific signaling pathways remain incompletely understood. Here, we summarize the reported functions, interactions, and signaling of macrophages with cancer cells during the metastatic cascade to bone. Specifically, we review and discuss how these specific interactions impact macrophages and their profiles to promote tumor development. We also discuss the potential of targeting this crosstalk to inhibit disease progression. Finally, we identify the remaining knowledge gaps that will need to be addressed in order to fully consider therapeutic targeting to improve clinical outcomes in cancer patients.

A high-throughput customized cytokinome screen of colon cancer cell responses to small-molecule oncology drugs

Inflammatory cytokines, chemokines, and growth factors are molecular messengers that circulate and have the capability to modify the tumor microenvironment and impact therapeutic response. The characterization of soluble mediators as biomarkers for diagnosis and prognosis is of interest in oncology. We utilize the cytokinome to characterize the response of colorectal tumor cell lines to selected small-molecules in oncology as a proof-of-concept dataset with immunomodulatory analyte heat map rankings for drug and cell line combinations. We observed overall trends in drug class effects with MEK-, BRAF-, PARP-inhibitors, and Imipridones in cytokine, chemokine, and growth factor responses that may help guide therapy selection. MEK-inhibitor treatment downregulated analytes VEGF, CXCL9/MIG, and IL-8/CXCL8 and upregulated CXCL14/BRAK, Prolactin, and CCL5/RANTES. BRAF-inhibitor treatment downregulated VEGF and IL-8/CXCL8, while increasing soluble TRAIL-R2. Treatment with PARP-inhibitors decreased CXCL9/MIG, IL-8/CXCL8, CCL3/MIP-1 alpha, VEGF, and CXCL14/BRAK, while treatment increased soluble TRAIL-R2 and prolactin. Treatment with Imipridones decreased CCL3/MIP-1 alpha, VEGF, CXCL14/BRAK, IL-8/CXCL8, and Prolactin and increased CXCL5/ENA-78. We also observed differential responses to therapeutics depending on the mutational profile of the cell line. In the future, a similar but larger dataset may be utilized in the clinic to aid in the prediction of patient response to immunomodulatory therapies based on tumor genotype.

Exploring the value of pleural fluid biomarkers for complementary pleural effusion disease examination

OBJECTIVE

Pleural fluid biomarkers are beneficial for the complementary diagnosis of pleural effusion etiologies. This study focuses on the multidimensional evaluation of deep learning to investigate the pleural effusion biomarkers value and the diagnostic utility of combining these markers, in distinguishing pleural effusion etiologies.

METHODS

Pleural effusion were divided into three groups according to the diagnosis and treatment guidelines: malignant pleural effusion (MPE), parapneumonic effusion (PPE), and congestive heart failure (CHF). First, the value of the biomarker was analyzed by a receiver operating characteristic (ROC) curve. Then by utilizing deep learning and entropy weight method (EWM), the clinical value of biomarkers was computed multidimensionally for complementary diagnosis of pleural effusion diseases.

RESULTS

There were significant differences in the six biomarkers, TP, ADA, CEA, CYFRA211, NSE, MNC% (p < 0.05) and no significant differences in three physical characteristics including color, transparency, specific gravity and six other biomarkers such as WBC, PNC%, MTC%, pH level, GLU, LDH (p > 0.05) among the three pleural effusion groups. The comprehensive test of pleural fluid biomarkers based on deep learning is of high accuracy. The clinical value of cytomorphology biomarkers WBC, MNC %, PNC %, MTC % was higher among pleural fluid biomarkers.

CONCLUSION

The clinical value of multi-dimensional analysis of biomarkers by deep learning and entropy weight method is different from the ROC curve analysis. It is suggested that during the clinical examination process, more attention should be paid to the cell morphology biomarkers, but the physical properties of the pleural fluid are less clinical significance.

Stromal fibroblasts shape the myeloid phenotype in normal colon and colorectal cancer and induce CD163 and CCL2 expression in macrophages

Colorectal cancer (CRC) accounts for about 10% of cancer deaths worldwide. Colon carcinogenesis is critically influenced by the tumor microenvironment. Cancer associated fibroblasts (CAFs) and tumor associated macrophages (TAMs) represent the major components of the tumor microenvironment. TAMs promote tumor progression, angiogenesis and tissue remodeling. However, the impact of the molecular crosstalk of tumor cells (TCs) with CAFs and macrophages on monocyte recruitment and their phenotypic conversion is not known in detail so far. In a 3D human organotypic CRC model, we show that CAFs and normal colonic fibroblasts are critically involved in monocyte recruitment and for the establishment of a macrophage phenotype, characterized by high CD163 expression. This is in line with the steady recruitment and differentiation of monocytes to immunosuppressive macrophages in the normal colon. Cytokine profiling revealed that CAFs produce M-CSF, and IL6, IL8, HGF and CCL2 secretion was specifically induced by CAFs in co-cultures with macrophages. Moreover, macrophage/CAF/TCs co-cultures increased TC invasion. We demonstrate that CAFs and macrophages are the major producers of CCL2 and, upon co-culture, increase their CCL2 production twofold and 40-fold, respectively. CAFs and macrophages expressing high CCL2 were also found in vivo in CRC, strongly supporting our findings. CCL2, CCR2, CSF1R and CD163 expression in macrophages was dependent on active MCSFR signaling as shown by M-CSFR inhibition. These results indicate that colon fibroblasts and not TCs are the major cellular component, recruiting and dictating the fate of infiltrated monocytes towards a specific macrophage population, characterized by high CD163 expression and CCL2 production.

Circulating Biomarkers of Colorectal Cancer (CRC)-Their Utility in Diagnosis and Prognosis

The global burden of colorectal cancer (CRC) is expected to increase, with 2.2 million new cases and 1.1 million annual deaths by 2030. Therefore, the establishment of novel biomarkers useful in the early diagnosis of CRC is of utmost importance. A number of publications have documented the significance of the overexpression of several specific proteins, such as inflammatory mediators, in CRC progression. However, little is known about the potential utility of these proteins as circulating blood tumor biomarkers of CRC. Therefore, in the present review we report the results of our previous original studies as well as the findings of other authors who investigated whether inflammatory mediators might be used as novel biomarkers in the diagnosis and prognosis of CRC. Our study revealed that among all of the tested proteins, serum M-CSF, CXCL-8, IL-6 and TIMP-1 have the greatest value in the diagnosis and progression of CRC. Serum TIMP-1 is useful in differentiating between CRC and colorectal adenomas, whereas M-CSF and CRP are independent prognostic factors for the survival of patients with CRC. This review confirms the promising significance of these proteins as circulating biomarkers for CRC. However, due to their non-specific nature, further validation of their sensitivity and specificity is required.

Immunomodulatory Activity of a Colony-stimulating Factor-1 Receptor Inhibitor in Patients with Advanced Refractory Breast or Prostate Cancer: A Phase I Study

PURPOSE

Tumor-associated macrophages correlate with increased invasiveness, growth, and immunosuppression. Activation of the colony-stimulating factor-1 receptor (CSF-1R) results in proliferation, differentiation, and migration of monocytes/macrophages. This phase I study evaluated the immunologic and clinical activity, and safety profile of CSF-1R inhibition with the mAb LY3022855.

PATIENTS AND METHODS

Patients with advanced refractory metastatic breast cancer (MBC) or metastatic castration-resistant prostate cancer (mCRPC) were treated with LY3022855 intravenously in 6-week cycles in cohorts: (A) 1.25 mg/kg every 2 weeks (Q2W); (B) 1.0 mg/kg on weeks 1, 2, 4, and 5; (C) 100 mg once weekly; (D)100 mg Q2W. mCRPC patients were enrolled in cohorts A and B; patients with MBC were enrolled in all cohorts. Efficacy was assessed by RECIST and Prostate Cancer Clinical Trials Working Group 2 criteria.

RESULTS

Thirty-four patients (22 MBC; 12 mCRPC) received ≥1 dose of LY3022855. At day 8, circulating CSF-1 levels increased and proinflammatory monocytes CD14^DIMCD16^BRIGHT decreased. Best RECIST response was stable disease in five patients with MBC (23%; duration, 82-302 days) and three patients with mCRPC (25%; duration, 50-124 days). Two patients with MBC (cohort A) had durable stable disease >9 months and a third patient with MBC had palpable reduction in a nontarget neck mass. Immune-related gene activation in tumor biopsies posttreatment was observed. Common any grade treatment-related adverse events were fatigue, decreased appetite, nausea, asymptomatic increased lipase, and creatine phosphokinase.

CONCLUSIONS

LY3022855 was well tolerated and showed evidence of immune modulation. Clinically meaningful stable disease >9 months was observed in two patients with MBC.

High neutrophil-lymphocyte ratio is not independently associated with worse survival or recurrence in patients with extremity soft tissue sarcoma

BACKGROUND

Soft tissue sarcomas are a heterogenous group of neoplasms without well-validated biomarkers. Cancer-related inflammation is a known driver of tumor growth and progression. Recent studies have implicated a high circulating neutrophil-lymphocyte ratio as a surrogate marker for the inflammatory tumor microenvironment and a poor prognosticator in multiple solid tumors, including colorectal and pancreatic cancers. The impact of circulating neutrophil-lymphocyte ratio in soft tissue sarcomas has yet to be elucidated.

METHODS

We performed a retrospective analysis of patients undergoing curative resection for primary or recurrent extremity soft tissue sarcomas at academic centers within the US Sarcoma Collaborative. Neutrophil-lymphocyte ratio was calculated retrospectively in treatment-naïve patients using blood counts at or near diagnosis.

RESULTS

A high neutrophil-lymphocyte ratio (≥4.5) was associated with worse survival on univariable analysis in patients with extremity soft tissue sarcomas (hazard ratio 2.07; 95% confidence interval, 1.54-2.8; P < .001). On multivariable analysis, increasing age (hazard ratio 1.03; 95% confidence interval, 1.02-1.04; P < .001), American Joint Committee on Cancer T3 (hazard ratio 1.89; 95% confidence interval, 1.16-3.09; P = .011), American Joint Committee on Cancer T4 (hazard ratio 2.36; 95% confidence interval, 1.42-3.92; P = .001), high tumor grade (hazard ratio 4.56; 95% confidence interval, 2.2-9.45; P < .001), and radiotherapy (hazard ratio 0.58; 95% confidence interval, 0.41-0.82; P = .002) were independently predictive of overall survival, but a high neutrophil-lymphocyte ratio was not predictive of survival (hazard ratio 1.26; 95% confidence interval, 0.87-1.82; P = .22).

CONCLUSION

Tumor inflammation as measured by high pretreatment neutrophil-lymphocyte ratio was not independently associated with overall survival in patients undergoing resection for extremity soft tissue sarcomas.

Oct4 promotes M2 macrophage polarization through upregulation of macrophage colony-stimulating factor in lung cancer

Background

Expression of Oct4 maintains cancer stem cell (CSC)-like properties in lung cancer cells and is correlated with poor prognosis of lung adenocarcinoma. M2-type tumor-associated macrophages (TAMs) promote cancer cell migration and metastasis. Tumor microenvironments promote monocyte differentiation into M2 TAMs via a complex cytokine-based connection. We explored the role of Oct4 in cytokine secretion in lung cancer and its impact on M2 TAM polarization.

Methods

Monocytes co-cultured with the conditioned medium from Oct4-overexpressing lung cancer cells were used to investigate M2 TAM differentiation. The inflammatory factors in the conditioned medium of Oct4-overexpressing A549 cells were examined using human inflammation antibody arrays. The correlations of Oct4, macrophage colony-stimulating factor (M-CSF), and M2 TAMs were validated in lung cancer cells, syngeneic mouse lung tumor models, and clinical samples of non-small cell lung cancer (NSCLC).

Results

Oct4-overexpressing A549 cells expressed elevated levels of M-CSF, which contributed to increased M2 macrophages and enhanced tumor migration. Overexpression of Oct4 enhanced tumor growth and reduced the survival of lung tumor-bearing mice, which was correlated with increased number of M2 macrophages in lung cancer. Notably, NSCLC patients with high expression levels of Oct4, M-CSF, and M2 TAMs had the poorest recurrence-free survival. A positive correlation between Oct4, M-CSF, and M2 TAMs was observed in the tumor tissue of NSCLC patient. Treatment with all-trans retinoic acid exerted anti-tumor effects and reduced M2 TAMs in tumor-bearing mice.

Conclusions

Our results indicate that Oct4 expressed by lung cancer cells promotes M2 macrophage polarization through upregulation of M-CSF secretion, leading to cancer growth and metastasis. Our findings also implicate that the Oct4/M-CSF axis in M2 macrophage polarization may be potential therapeutic targets for lung cancer.

Metabolic Remodeling as a Way of Adapting to Tumor Microenvironment (TME), a Job of Several Holders

The microenvironment depends and generates dependence on all the cells and structures that share the same niche, the biotope. The contemporaneous view of the tumor microenvironment (TME) agrees with this idea. The cells that make up the tumor, whether malignant or not, behave similarly to classes of elements within a living community. These elements inhabit, modify and benefit from all the facilities the microenvironment has to offer and that will contribute to the survival and growth of the tumor and the progression of the disease.The metabolic adaptation to microenvironment is a crucial process conducting to an established tumor able to grow locally, invade and metastasized. The metastatic cancer cells are reasonable more plastic than non-metastatic cancer cells, because the previous ones must survive in the microenvironment where the primary tumor develops and in addition, they must prosper in the microenvironment in the metastasized organ.The metabolic remodeling requires not only the adjustment of metabolic pathways per se but also the readjustment of signaling pathways that will receive and obey to the extracellular instructions, commanding the metabolic adaptation. Many diverse players are pivotal in cancer metabolic fitness from the initial signaling stimuli, going through the activation or repression of genes, until the phenotype display. The new phenotype will permit the import and consumption of organic compounds, useful for energy and biomass production, and the export of metabolic products that are useless or must be secreted for a further recycling or controlled uptake. In the metabolic network, three subsets of players are pivotal: (1) the organic compounds; (2) the transmembrane transporters, and (3) the enzymes.This chapter will present the "Pharaonic" intent of diagraming the interplay between these three elements in an attempt of simplifying and, at the same time, of showing the complex sight of cancer metabolism, addressing the orchestrating role of microenvironment and highlighting the influence of non-cancerous cells.

Monocytes and Macrophages in Cancer: Unsuspected Roles

The behavior of cancer is undoubtedly affected by stroma. Macrophages belong to this microenvironment and their presence correlates with reduced survival in most cancers. After a tumor-induced "immunoediting", these monocytes/macrophages, originally the first line of defense against tumor cells, undergo a phenotypic switch and become tumor-supportive and immunosuppressive.The influence of these tumor-associated macrophages (TAMs) on cancer is present in all traits of carcinogenesis. These cells participate in tumor initiation and growth, migration, vascularization, invasion and metastasis. Although metastasis is extremely clinically relevant, this step is always reliant on the angiogenic ability of tumors. Therefore, the formation of new blood vessels in tumors assumes particular importance as a limiting step for disease progression.Herein, the once unsuspected roles of macrophages in cancer will be discussed and their importance as a promising strategy to treat this group of diseases will be reminded.

Tissue Site and the Cancer Immunity Cycle

Checkpoint blockade immunotherapy (CBT) has revolutionized cancer treatment; however, the cellular and molecular factors that govern responsiveness to immunotherapy remain poorly understood. One emerging area of clinical importance is differential responsiveness to CBT across different tissue sites of tumor growth. Each tissue site in the body can contain unique tissue-resident immune cells from both the lymphoid and the myeloid compartment and differences in tissue-specific immune cell composition might predispose tumors in certain tissue sites to be more or less responsive to immunotherapy. Understanding the interplay between tissue-resident and systemic immune responses against tumors will help to determine how to better therapeutically target the immune system to fight cancer. This review summarizes clinical and preclinical investigations of tissue-specific antitumor immune responses and how they influence the tumor immune microenvironment and the efficacy of immunotherapy.

CSF-1 Overexpression Predicts Poor Prognosis in Upper Tract Urothelial Carcinomas

Background

Colony-stimulating factor-1 (CSF-1) is a homodimeric glycoprotein. The main role of CSF-1 is as a hematopoietic growth factor that modulates proliferation, differentiation, and survival of macrophages. Moreover, CSF-1 has also been reported to be aberrantly expressed in several human cancers. However, the precise role of CSF-1 in upper tract urothelial carcinomas (UTUC) has not been studied. In this research, we examined the clinical significance of CSF-1 expression in UTUC.

Materials and Methods

One hundred twelve cancer tissue samples of UTUC from patients were included in this study, and the other cohort of 35 UTUC were paired cancer-adjacent normal samples. CSF-1 expression was evaluated by immunohistochemistry, and the association of CSF-1 expression with different clinicopathological variables was analyzed.

Results

CSF-1 expression was higher in UTUC than in the normal urothelium (P = 0.005). The CSF-1 expression was primarily localized in the nucleus and was significantly correlated with tumor size (P = 0.04) and patients who had a high stage (P < 0.001), distant metastasis (P = 0.006), recurrence (P = 0.003), and cancer death (P = 0.005). High CSF-1 expression was correlated with poor disease-free survival (P = 0.008) and cancer-specific survival (P = 0.001). Our results also used univariate and multivariable analyses, which found that high CSF-1 expression was an independent predictor of poor disease-free survival (hazard ratio = 2.56; P = 0.007) and cancer-specific survival (hazard ratio = 5.14; P = 0.022).

Conclusions

Our findings indicate that the expression of CSF-1 is a potential prognostic marker for predicting patient survival and recurrence in UTUC.

Hypoxia and the Metastatic Niche

Metastasis is considered the latest stage of cancer development; however, metastasis occurs earlier than it can be detected. Metastatic sites are actively remodeled by secretory factors including growth factors, chemokines and cytokines, extracellular matrix (ECM) enzymes, and exosomes produced by the primary cancer tissues. Many of the associated-secretory factors are abundantly induced by inflammation and hypoxia. These secretory factors modify the ECM, immune composition, and blood vessel permeability of the future metastatic sites, a process termed 'metastatic niche formation.' In general, ECM is modified to enhance the attachment of other cell types or cancer cells to establish a growth-factor rich metastatic niche. Immune-suppressive cells such as tumor-associated macrophages (TAMs) and regulatory T cells (Tregs) dominate the metastatic niche to allow metastatic cancer cells to bypass immune surveillance and propagate. Endothelial cell-to-cell junctions of blood vessels are loosened to enhance the penetrance of metastatic cancer cells to the metastatic sites. Different metastatic tissues have unique ECM constituents, resident immune cells, and anatomical positions linked with the circulatory system; therefore, many cancer types have their own metastatic pattern, and they favor metastasis to specific organs. Some of the remodeling events represent the earliest step of metastasis, even preceding the detachment of cancer cells from the primary tumor site. Understanding how the metastatic niche is formed is important for the development of drugs to prevent the earliest step of metastasis and advance our understanding of organotrophic metastasis. This review summarizes the major findings in the field of metastatic niche highlighting the role of hypoxia.

Colony-stimulating factor-1 receptor provides a growth advantage in epithelial cancer cell line A431 in the presence of epidermal growth factor receptor inhibitor gefitinib

Although epidermal growth factor receptor (EGFR) has been identified as a potent "oncogenic driver" in various tumors of epithelial origin, EGFR-targeted therapies are often of limited success. One of the challenges of improving targeted therapies is to overcome bypassing signaling pathways. Analysis of RNA-seq data of 1006 cell lines from the Cancer Cell Line Encyclopedia (CCLE) revealed that more than 12% of carcinoma cell lines expressed markedly elevated mRNA levels of colony-stimulating factor (CSF)-1 receptor (CSF-1R). Since epithelial cells also express CSF-1, elevated levels of CSF-1R may participate in providing alternative growth and survival signals under targeted therapies. To address this question, we ectopically expressed CSF-1R in A431 cells that express EGFR at high levels, but no biologically relevant level of CSF-1R. In the presence of EGFR inhibitor gefitinib, CSF-1R provided a significant growth advantage in A431 cells. As expected, activation of both receptors, EGFR or CSF-1R, induced phosphorylation of extracellular signal-regulated kinase (Erk)1/2, Akt, protein kinase C (PKC) and signal transducer and activator of transcription (STAT)3. However, EGFR, but not CSF-1R, also induced STAT5 phosphorylation. Inhibitor of phosphatidylinositol 3-kinase (PI3K) (AZD8186), MAPK/ERK kinase (MEK)1/2 (U0126), PKCs (Bisindolylmaleimide I or Gö6976) or STAT3 (Stattic) partially reduced proliferation of CSF-1R expressing A431 cells in the presence of gefitinib. Moreover, multi-kinase inhibitor, cabozantinib, suppressed CSF-1R activation and drastically reduced cell growth when combined with gefitinib. These data suggest that CSF-1R has the potential to reduce sensitivity to gefitinib and may be involved in resistance development.

Metabolic cooperation between cancer and non-cancerous stromal cells is pivotal in cancer progression

The way cancer cells adapt to microenvironment is crucial for the success of carcinogenesis, and metabolic fitness is essential for a cancer cell to survive and proliferate in a certain organ/tissue. The metabolic remodeling in a tumor niche is endured not only by cancer cells but also by non-cancerous cells that share the same microenvironment. For this reason, tumor cells and stromal cells constitute a complex network of signal and organic compound transfer that supports cellular viability and proliferation.

The intensive dual-address cooperation of all components of a tumor sustains disease progression and metastasis. Herein, we will detail the role of cancer-associated fibroblasts, cancer-associated adipocytes, and inflammatory cells, mainly monocytes/macrophages (tumor-associated macrophages), in the remodeling and metabolic adaptation of tumors.

Heterogeneous effects of M-CSF isoforms on the progression of MLL-AF9 leukemia

Macrophage colony-stimulating factor (M-CSF) regulates both malignant cells and microenvironmental cells. Its splicing isoforms show functional heterogeneity. However, their roles on leukemia have not been well established. Here, the expression of total M-CSF in patients with hematopoietic malignancies was analyzed. The roles of M-CSF isoforms on the progression of acute myeloid leukemia (AML) were studied by establishing MLL-AF9-induced mouse AML models with high level membrane-bound M-CSF (mM-CSF) or soluble M-CSF (sM-CSF). Total M-CSF was highly expressed in myeloid leukemia patients. Furthermore, mM-CSF but not sM-CSF prolonged the survival of leukemia mice. While sM-CSF was more potent to promote proliferation and self-renew, mM-CSF was more potent to promote differentiation. Moreover, isoforms had different effects on leukemia-associated macrophages (LAMs) though they both increase monocytes/macrophages by growth-promoting and recruitment effects. In addition, mM-CSF promoted specific phagocytosis of leukemia cells by LAMs. RNA-seq analysis revealed that mM-CSF enhanced phagocytosis-associated genes and activated oxidative phosphorylation and metabolism pathway. These results highlight heterogeneous effects of M-CSF isoforms on AML progression and the mechanisms of mM-CSF, that is, intrinsically promoting AML cell differentiation and extrinsically enhancing infiltration of macrophages and phagocytosis by macrophages, which may provide potential clues for clinical diagnosis and therapy.

Colony stimulating factor-1 in saliva in relation to age, smoking, and oral and systemic diseases

Colony stimulating factor (CSF)-1 is a growth factor that stimulates the survival, proliferation and differentiation of mononuclear phagocytes, which has been implicated in several inflammatory diseases. This study evaluated the possible influence of age, sex, smoking, periodontitis, caries, and several systemic conditions on salivary levels of CSF-1. Four-hundred and forty-one individuals were enrolled in this study. All participants answered a health questionnaire and underwent a comprehensive oral examination. Stimulated saliva was collected and CSF-1 levels were analysed by enzyme-linked immunosorbent assay. Salivary levels of CSF-1 were significantly increased in participants over 64 years old and in non-smoking individuals, whereas no difference was observed between men and women. Individuals having periodontitis and manifest caries had significantly higher levels of CSF-1. Participants with muscle and joint disease exhibited increased CSF-1 levels as compared to those without. Age, smoking, percentage of pockets ≥4 mm, number of manifest caries lesions, and presence of tumor were associated with CSF-1 levels. Salivary levels of CSF-1 are associated with age, smoking, periodontitis, manifest caries, and the presence of muscle and joint diseases and tumors. CSF-1 might be a promising biomarker candidate in saliva of both local and systemic conditions that needs further investigation.

CSF-1 regulates the function of monocytes in Crohn's disease patients in remission

During the flare-ups of Crohn's disease (CD) patients, circulating leukocytes actively migrate toward the inflamed sites. During the remission, the lack of symptoms does not necessarily imply immunological remission. To decipher inflammatory mechanisms still operating during CD remission, we compared the expression of chemokine receptors on monocytes from CD and healthy donors (HD), and how these differences could modulate monocyte maturation and cytokine production. Flow cytometry analysis showed a higher expression of CCR5 on monocytes from CD patients than those from HD after 24 h. This CCR5 upregulation was associated with the spontaneous production of CSF-1 and IL-10. The higher expression of CCR5 on CD monocytes increased their migratory pattern in response to CCL5. Signaling through CCR5/CCL5 increased CD163 and HLA-DR expression and diminished TLR4-induced TNF-α and IL-6 secretion during monocyte differentiation. When we analyzed clinical parameters, patients treated with azathioprine had the highest CSF-1 levels and CCR5 expression. Our results suggest that monocytes from CD patients in remission produced high levels of CSF-1 that upregulate CCR5 expression. Consequently, monocytes differentiated in these conditions had a characteristic phenotype and lower production of inflammatory cytokines. The treatment with azathioprine could be responsible for this anti-inflammatory profile of monocytes.

Six1 promotes colorectal cancer growth and metastasis by stimulating angiogenesis and recruiting tumor-associated macrophages

The homeoprotein Six1 is overexpressed in many human cancers and is associated with increased tumor progression and metastasis. Recent studies have shown that Six1 is associated with poorer overall survival in advanced-stage colorectal cancer (CRC). In the current study, we explored the functional changes and molecular events associated with Six1 overexpression in a mouse model of CRC. An orthotopic model and a splenic injection metastasis model were used to investigate the role of Six1 in CRC tumor growth and metastasis using mouse colon adenocarcinoma MC38 cells overexpressing Six1. We found that overexpression of Six1 dramatically promotes CRC tumor growth and metastasis in vivo. Six1 overexpression in MC38 increased protein levels of aldehyde dehydrogenase-1 and expanded CD44+/CD166+ populations, indicating Six1 increased features of cancer stem cells. In addition, Six1 overexpression stimulated angiogenesis by upregulating the expression of vascular endothelial growth factor (VEGF). Six1-overexpressing tumor cells recruited tumor-associated macrophages (TAM) by increasing the expression of macrophage-specific colony stimulating factor, chemokine (C-C motif) ligand 2/5 and VEGF, further facilitating CRC tumor growth and metastasis. Furthermore, we determined that Six1 activated mitogen-activated protein kinase (MAPK) signaling in CRC cells. In summary, our studies strongly suggest that Six1 overexpression promotes CRC growth and metastasis and remodels tumor stroma by stimulating angiogenesis and recruiting TAM. MAPK activation may be a pivotal event in Six1-associated tumor progression, which may provide opportunities for pharmacologic intervention.

Diverse in vivo effects of soluble and membrane-bound M-CSF on tumor-associated macrophages in lymphoma xenograft model

Macrophage colony-stimulating factor (M-CSF) is an important cytokine for monocyte/macrophage lineage. Secretory M-CSF (sM-CSF) and membrane-bound M-CSF (mM-CSF) are two major alternative splicing isoforms. The functional diversity of these isoforms in the activation of tumor-associated macrophages (TAMs), especially in lymphoma microenvironment, has not been documented. Here, we studied the effects of M-CSF isoforms on TAMs in xenograft mouse model. More infiltrating TAMs were detected in microenvironment with mM-CSF and sM-CSF. TAMs could be divided into three subpopulations based on their expression of CD206 and Ly6C. While sM-CSF had greater potential to recruit and induce differentiation of TAMs and TAM subpopulations, mM-CSF had greater potential to induce proliferation of TAMs and TAM subpopulations. Though both isoforms educated TAMs and TAM subpopulations to M2-like macrophages, mM-CSF and sM-CSF induced different spectrums of phenotype-associated genes in TAMs and TAM subpopulations. These results suggested the diverse effects of M-CSF isoforms on the activation of TAMs and TAM subpopulations in lymphoma microenvironments.

Macrophage colony-stimulating factor expressed in non-cancer tissues provides predictive powers for recurrence in hepatocellular carcinoma

AIM

To investigate the role of macrophage colony-stimulating factor (M-CSF) in patients with hepatocellular carcinoma (HCC) after surgery.

METHODS

Expression of M-CSF, distribution of M2 macrophages (MΦs), and angiogenesis were assessed in the liver, including tumors and peritumoral liver tissues. The prognostic power of these factors was assessed. Mouse isolated hepatic MΦs or monocytes were cultured with media containing M-CSF. The concentration of vascular endothelial growth factor (VEGF) in media was assessed. Furthermore, the role of the M-CSF-matured hepatic MΦs on proliferation of the vascular endothelial cell (VEC) was investigated.

RESULTS

A strong correlation between the expressions of M-CSF and CD163 was observed in the peritumoral area. Also, groups with high density of M-CSF, CD163 or CD31 showed a significantly shorter time to recurrence (TTR) than low density groups. Multivariate analysis revealed the expression of M-CSF or hepatic M2MΦs in the peritumoral area as the most crucial factor responsible for shorter TTR. Moreover, the expression of M-CSF and hepatic M2MΦs in the peritumoral area had better predictable power of overall survival. Values of VEGF in culture media were significantly greater in the hepatic MΦs compared with the monocytes. Proliferation of the VEC was greatest in the cells co-cultured with hepatic MΦs when M-CSF was present in media.

CONCLUSION

M-CSF increases hepatocarcinogenesis, most likely by enhancing an angiogenic factor derived from hepatic MΦ and could be a useful target for therapy against HCC.

Pleural Effusions from Patients with Mesothelioma Induce Recruitment of Monocytes and Their Differentiation into M2 Macrophages

INTRODUCTION

Mesothelioma is a rare and aggressive cancer related to asbestos exposure. We recently showed that pleural effusions (PEs) from patients with mesothelioma contain high levels of the C-C motif chemokine ligand 2 (CCL2) inflammatory chemokine. In the present work, we studied the effect of CCL2 contained in mesothelioma samples, particularly on monocyte recruitment. Then, we studied the fate of these monocytes in malignant pleural mesothelioma (MPM) PEs and their impact on tumor cells' properties.

METHODS

The implication of CCL2 in monocyte recruitment was evaluated using transmigration assays and a CCL2 blocking antibody. The phenotype of macrophages was determined by flow cytometry and enzyme-linked immunosorbent assay. Immunohistochemical analysis was used to support the results. Cocultures of macrophages with mesothelioma cells were performed to study cancer cell proliferation and resistance to treatment.

RESULTS

We showed that CCL2 is a major factor of monocyte recruitment induced by MPM samples. Macrophages obtained in MPM samples were M2 macrophages (high CD14, high CD163, and interleukin-10 secretion after activation). The colony-stimulating factor 1 receptor/macrophage colony-stimulating factor (M-CSF) pathway is implicated in M2 polarization, and high levels of M-CSF were measured in MPM samples compared with benign PE (4.17 ± 2.75 ng/mL and 1.94 ± 1.47 ng/mL, respectively). Immunohistochemical analysis confirmed the presence of M2 macrophages in pleural and peritoneal mesothelioma. Finally, we showed that M2 macrophages increased mesothelioma cell proliferation and resistance to treatment.

CONCLUSIONS

These results demonstrate the implication of CCL2 in MPM pathogenesis and designate M-CSF as a new potential biomarker of MPM. This study also identifies CCL2 and colony-stimulating factor 1 receptor/M-CSF as interesting new targets to modulate pro-tumorigenic properties of the tumor microenvironment.

The role of myeloid cells in cancer therapies

Recent clinical trials have demonstrated the ability to durably control cancer in some patients by manipulating T lymphocytes. These immunotherapies are revolutionizing cancer treatment but benefit only a minority of patients. It is thus a crucial time for clinicians, cancer scientists and immunologists to determine the next steps in shifting cancer treatment towards better cancer control. This Review describes recent advances in our understanding of tumour-associated myeloid cells. These cells remain less studied than T lymphocytes but have attracted particular attention because their presence in tumours is often linked to altered patient survival. Also, experimental studies indicate that myeloid cells modulate key cancer-associated activities, including immune evasion, and affect virtually all types of cancer therapy. Consequently, targeting myeloid cells could overcome limitations of current treatment options.

Prognostic role of lymphocyte to monocyte ratio for patients with cancer: evidence from a systematic review and meta-analysis

Inflammation influences cancer development and progression, and a low lymphocyte to monocyte ratio (LMR) has been reported to be a poor prognostic indicator in several malignancies. Here we quantify the prognostic impact of this biomarker and assess its consistency in various cancers. Eligible studies were retrieved from PubMed, Embase and Web of Science databases. Overall survival (OS) was the primary outcome, cancer-specific survival (CSS), disease-free survival (DFS), recurrence-free survival (RFS), and progression-free survival (PFS) were secondary outcomes. Pooled hazard ratios (HRs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. Fifty-six studies comprising 20,248 patients were included in the analysis. Overall, decreased LMR was significantly associated with shorter OS in non-hematological malignancy (HR: 0.59, 95% CI: 0.53-0.66; P < 0.001) and hematological malignancy (HR: 0.44, 95% CI: 0.34-0.56; P < 0.001). Similar results were found in CSS, DFS, RFS and PFS. Moreover, low LMR was significantly associated with some clinicopathological characteristics that are indicative of poor prognosis and disease aggressiveness. By these results, we conclude that a decreased LMR implied poor prognosis in patients with cancer and could serve as a readily available and inexpensive biomarker for clinical decision.

Role of the colony-stimulating factor (CSF)/CSF-1 receptor axis in cancer

Cancer cells employ a variety of mechanisms to evade apoptosis and senescence. Pre-eminent among these is the aberrant co-expression of growth factors and their ligands, forming an autocrine growth loop that promotes tumour formation and progression. One growth loop whose transforming potential has been repeatedly demonstrated is the CSF-1/CSF-1R axis. Expression of CSF-1 and/or CSF-1R has been documented in a number of human malignancies, including breast, prostate and ovarian cancer and classical Hodgkin's lymphoma (cHL). This review summarizes the large body of work undertaken to study the role of this cytokine receptor system in malignant transformation. These studies have attributed a key role to the CSF-1/CSF-1R axis in supporting tumour cell survival, proliferation and enhanced motility. Moreover, increasing evidence implicates paracrine interactions between CSF-1 and its receptor in defining a tumour-permissive and immunosuppressive tumour-associated stroma. Against this background, we briefly consider the prospects for therapeutic targeting of this system in malignant disease.

Follicular thyroid carcinoma but not adenoma recruits tumor-associated macrophages by releasing CCL15

BACKGROUND

The differential diagnosis of follicular thyroid carcinoma (FTC) and follicular adenoma (FA) before surgery is a clinical challenge. Many efforts have been made but most focusing on tumor cells, while the roles of tumor associated macrophages (TAMs) remained unclear in FTC. Here we analyzed the differences between TAMs in FTC and those in FA.

METHODS

We first analyzed the density of TAMs by CD68 immunostaining in 59 histologically confirmed FTCs and 47 FAs. Cytokines produced by FTC and FA were profiled using antibody array, and validated by quantitative PCR. Chemotaxis of monocyte THP-1 was induced by condition medium of FTC cell lines (FTC133 and WRO82-1) with and without anti-CCL15 neutralizing antibody. Finally, we analyzed CCL15 protein level in FTC and FA by immunohistochemistry.

RESULTS

The average density of CD68(+) cells was 9.5 ± 5.4/field in FTC, significantly higher than that in FA (4.9 ± 3.4/field, p < 0.001). Subsequently profiling showed that CCL15 was the most abundant chemokine in FTC compared with FA. CCL15 mRNA in FTC was 51.4-folds of that in FA. CM of FTC cell lines induced THP-1 cell chemotaxis by 33 ~ 77%, and anti-CCL15 neutralizing antibody reduced THP-1 cell migration in a dose-dependent manner. Moreover, we observed positive CCL15 immunostaining in 67.8% of FTCs compared with 23.4% of FAs.

CONCLUSION

Our study suggested FTC might induce TAMs infiltration by producing CCL15. Measurement of TAMs and CCL15 in follicular thyroid lesions may be applied clinically to differentiate FTC from FA pre-operation.

Pretreatment lymphocyte to monocyte ratio as a predictor of prognosis in patients with early-stage triple-negative breast cancer

Recent studies have shown that the lymphocyte to monocyte ratio (LMR) is a useful prognostic factor in various cancers. The purpose of the current study was to investigate the association between pretreatment LMR, disease-free survival (DFS), and overall survival (OS) in patients with early-stage (I to III) triple-negative breast cancer (TNBC). Pretreatment LMR with corresponding clinical features from 230 TNBC patients was noted. A receiver operating characteristic (ROC) curve for survival prediction was plotted to verify the optimal cutoff values for LMR, lymphocyte, and monocyte counts. The difference between variables was calculated using chi-square tests. The Kaplan-Meier method and univariate and multivariate Cox regression models were applied to assess OS and DFS. Based on the ROC analysis, the optimal cutoff point for LMR was 4.7. Associations between high LMR (≥4.7) and significantly small tumor size (P = 0.005) and TNM stage (P = 0.013) were found, although there was no significant association for other clinical pathological factors. In the multivariate analysis, LMR was a significant predictive factor for both OS (hazard ratio [HR] = 0.42; 95 % confidence interval [CI], 0.19-0.95; P < 0.001) and DFS (HR = 0.40; 95 % CI, 0.20-0.79; P < 0.001). In addition, the predictive values of the OS and DFS were also observed for absolute counts of lymphocytes (P < 0.001) and monocytes (P < 0.001). Our study suggests that pretreatment LMR may be a predictive factor for long-term survival in patients with early-stage TNBC.

Control of Macrophage Dynamics as a Potential Therapeutic Approach for Clinical Disorders Involving Chronic Inflammation

Macrophages are a well recognized player of both innate and adaptive immunity and have emerged as a key regulator of systemicmetabolism, hematopoiesis, vasculogenesis, apoptosis, malignancy, and reproduction. Such pleiotropic roles of macrophages are mirrored by their protean features. Upon environmental. challenges, macrophages redistribute and differentiate in situ and contribute to the multiple disease states by exerting protective and pathogenic effects. The environmental challenges include cytokines, chemokines, lipid mediators, and extrinsic insults, such as food and pathogenic bacteria. In addition, homeostasis and the activation state of macrophages are influenced by various metabolites from a commensal microbe that colonizes epithelial and mucosal surfaces, such as the lungs, intestines, and skin. In this review, we describe macrophage differentiation, polarization, and various functions in chronic disease states, including chronic inflammatory bowel disease, tumorigenesis, metabolism and obesity, and central nervous system demyelinating disorders. Controlling the macrophage dynamics to affect the pathologic states is considered to be an important therapeutic approach for many clinical disorders involving chronic inflammation.

Analysis of circulating DNA and protein biomarkers to predict the clinical activity of regorafenib and assess prognosis in patients with metastatic colorectal cancer: a retrospective, exploratory analysis of the CORRECT trial

BACKGROUND

Tumour mutational status is an important determinant of the response of metastatic colorectal cancer to targeted treatments. However, the genotype of the tissue obtained at the time of diagnosis might not accurately represent tumour genotype after multiple lines of treatment. This retrospective exploratory analysis investigated the clinical activity of regorafenib in biomarker subgroups of the CORRECT study population defined by tumour mutational status or plasma protein levels.

METHODS

We used BEAMing technology to identify KRAS, PIK3CA, and BRAF mutations in DNA obtained from the plasma of 503 patients with metastatic colorectal cancer who enrolled in the CORRECT trial. We quantified total human genomic DNA isolated from plasma samples for 503 patients using a modified version of human long interspersed nuclear element-1 (LINE-1) quantitive real-time PCR. We also measured the concentration of 15 proteins of interest-angiopoietin 2, interleukin 6, interleukin 8, placental growth factor, soluble TIE-1, soluble VEGFR1, VEGF-A, VEGF-C, VEGF-D, VEGF-A isoform 121, bone morphogenetic protein 7, macrophage colony-stimulating factor, stromal cell-derived factor-1, tissue inhibitor of metalloproteinase 2, and von Willebrand factor-in plasma samples from 611 patients. We did correlative analyses of overall survival and progression-free survival in patient subgroups based on mutational status, circulating DNA concentration, and protein concentrations. The CORRECT trial was registered with ClinicalTrials.gov, number NCT01103323.

FINDINGS

Tumour-associated mutations were readily detected with BEAMing of plasma DNA, with KRAS mutations identified in 349 (69%) of 503 patients, PIK3CA mutations in 84 (17%) of 503 patients, and BRAF mutations in 17 (3%) of 502 patients. We did not do correlative analysis based on BRAF genotype because of the low mutational frequency detected for this gene. Some of the most prevalent individual hot-spot mutations we identified included: KRAS (KRAS G12D, 116 [28%] of 413 mutations; G12V, 72 [17%]; and G13D, 67 [16%]) and PIK3CA (PIK3CA E542K, 27 [30%] of 89 mutations; E545K, 37 [42%]; and H1047R, 12 [14%]). 41 (48%) of 86 patients who had received anti-EGFR therapy and whose archival tumour tissue DNA was KRAS wild-type in BEAMing analysis were identified as having KRAS mutations in BEAMing analysis of fresh plasma DNA. Correlative analyses suggest a clinical benefit favouring regorafenib across patient subgroups defined by KRAS and PIK3CA mutational status (progression-free survival with regorafenib vs placebo: hazard ratio [HR] 0·52, 95% CI 0·35-0·76 for KRAS wild-type; HR 0·51, 95% CI 0·40-0·65 for KRAS mutant [KRAS wild type vs mutant, pinteraction=0·74]; HR 0·50, 95% CI 0·40-0·63 for PIK3CA wild-type; HR 0·54, 95% CI 0·32-0·89 for PIK3CA mutant [PIK3CA wild-type vs mutant, pinteraction=0·85]) or circulating DNA concentration (progression-free survival with regorafenib vs placebo: HR 0·53, 95% CI 0·40-0·71, for low circulating DNA concentrations; HR 0·52, 95% CI 0·40-0·70, for high circulating DNA concentrations; low vs high circulating DNA, pinteraction=0·601). With the exception of von Willebrand factor, assessed with the median cutoff method, plasma protein concentrations were also not associated with regorafenib activity in terms of progression-free survival. In univariable analyses, the only plasma protein that was associated with overall survival was TIE-1, high concentrations of which were associated with longer overall survival compared with low TIE-1 concentrations. This association was not significant in multivariable analyses.

INTERPRETATION

BEAMing of circulating DNA could be a viable approach for non-invasive analysis of tumour genotype in real time and for the identification of potentially clinically relevant mutations that are not detected in archival tissue. Additionally, the results show that regorafenib seems to be consistently associated with a clinical benefit in a range of patient subgroups based on mutational status and protein biomarker concentrations.

FUNDING

Bayer HealthCare Pharmaceuticals.

Cytokine profile and prognostic significance of high neutrophil-lymphocyte ratio in colorectal cancer

Background:

High circulating neutrophil-lymphocyte ratio (NLR) appears to be prognostic in metastatic colorectal cancer (mCRC). We investigated the relationship of NLR with circulating cytokines and molecular alterations.

Methods:

We performed retrospective analyses on multiple cohorts of CRC patients (metastatic untreated (n=166), refractory metastatic (n=161), hepatectomy (n=198), stage 2/3 (n=274), and molecularly screened (n=342)). High NLR (ratio of absolute neutrophil-to-lymphocyte counts in peripheral blood) was defined as NLR>5. Plasma cytokines were evaluated using multiplex-bead assays. Kaplan–Meier estimates, non-parametric correlation analysis, and hierarchical cluster analyses were used.

Results:

High NLR was associated with poor prognosis in mCRC (hazard ratio (HR) 1.73; 95% confidence interval (CI):1.03–2.89; P=0.039) independent of known prognostic factors and molecular alterations (KRAS/NRAS/BRAF/PIK3CA/CIMP). High NLR correlated with increased expression of interleukin 6 (IL-6), IL-8, IL-2Rα, hepatocyte growth factor, macrophage-colony stimulating factor, and vascular epidermal growth factor in exploratory (n=39) and validation (n=166) cohorts. Fourteen additional cytokines correlated with high NLR in the validation cohort. All 20 cytokines fell into three major clusters: inflammatory cytokines, angiogenic cytokines, and epidermal growth factor ligands. In mCRC, composite stratification based on NLR-cytokine score provided enhanced prognostic information (HR 2.09; 95% CI: 1.59–2.76; P<0.001) over and above NLR.

Conclusions:

High NLR is an independent poor prognostic marker in CRC and correlates with a distinct cytokine profile related to key biological processes involved in carcinogenesis. A composite NLR-cytokine stratification has enhanced prognostic value in mCRC.

Modulating the tumor microenvironment with RNA interference as a cancer treatment strategy

The tumor microenvironment is composed of accessory cells and immune cells in addition to extracellular matrix (ECM) components. The stromal compartment interacts with cancer cells in a complex crosstalk to support tumor development. Growth factors and cytokines produced by stromal cells support the growth of tumor cells and promote interaction with the vasculature to enhance tumor progression and invasion. The activation of autocrine and paracrine oncogenic signaling pathways by growth factors, cytokines, and proteases derived from both tumor cells and the stromal compartment is thought to play a major role in assisting tumor cells during metastasis. Consequently, targeting tumor-stroma interactions by RNA interference (RNAi)-based approaches is a promising strategy in the search for novel treatment modalities in human cancer. Recent advances in packaging technology including the use of polymers, peptides, liposomes, and nanoparticles to deliver small interfering RNAs (siRNAs) into target cells may overcome limitations associated with potential RNAi-based therapeutics. Newly developed nonviral gene delivery approaches have shown improved anticancer efficacy suggesting that RNAi-based therapeutics provide novel opportunities to elicit significant gene silencing and induce regression of tumor growth. This chapter summarizes our current understanding of the tumor microenvironment and highlights some potential targets for therapeutic intervention with RNAi-based cancer therapeutics.

Macrophage colony-stimulating factor and cancer: a review

Tumor growth is influenced by a wide variety of external and internal factors. One of the most important mediators of tumor development is our immune system. The nonstop surveillance of the immune system was originally expected to clear the transformed cells from the body and guard against the development of tumor. But contradictory evidences are reported to show the involvement of immune system in supporting the growth and spread of tumor. Tumor infiltrating immune cells, in addition to harboring immunosuppressive activities, also promote angiogenesis and metastasis of tumor. Many growth factors and cytokines are involved in shaping this complex immune microenvironment of the tumor. Macrophage colony-stimulating factor (MCSF) is one such growth factor which is overexpressed in many tumors. In this review, we summarize the basic biology of MCSF, its role in cancer and discuss the involvement of tumor-associated macrophages (TAMs) in tumor development.

Macrophage density and macrophage colony-stimulating factor expression predict the postoperative prognosis in patients with intrahepatic cholangiocarcinoma

PURPOSES

Macrophages are included in the stromal compartments in various neoplasms, and their behavior against tumors is diverse. The aim of this study was to examine the role of tumor-infiltrating macrophages and their main regulator, macrophage colony-stimulating factor (M-CSF), in intrahepatic cholangiocarcinoma (ICC).

METHODS

Macrophage density and M-CSF expression in 39 resected ICC specimens were immunohistochemically evaluated in the central and peripheral areas of tumors, which were defined as fields more than and within 500 μm from the invasive front, respectively. The number of CD68-positive macrophages was counted using an image-analyzing software program. The relationship between these results and other clinicopathological factors and the postoperative prognosis were evaluated.

RESULTS

Sporadic M-CSF expression in cancer cells around the peripheral area was observed in fourteen patients. M-CSF-positive ICCs showed a higher macrophage density in the tumor-peripheral area than did M-CSF-negative ICCs. M-CSF expression and higher macrophage density in the tumor-peripheral area were related to a better postoperative prognosis, whereas a higher macrophage density in the central area was one of the significant risk factors for a poor prognosis in a univariate analysis.

CONCLUSION

Tumor-peripheral macrophage infiltration, presumably dependent on M-CSF, and M-CSF-independent tumor-central macrophage infiltration are predictive factors for better and worse postoperative prognosis in ICC patients, respectively. The tumor microenvironment, such as the presence of hypoxia, may affect the behavior of infiltrating macrophages in ICC.

Targeting tumor-infiltrating macrophages to combat cancer

Tumor-associated macrophages are one of the major constituents of tumor stroma in many solid tumors and there is compelling preclinical and clinical evidence that macrophages promote cancer initiation and malignant progression. Therefore, these cells represent potential targets for therapeutic benefit. In this review, we will summarize macrophage phenotypic heterogeneity, the current understanding of how tumors take advantage of macrophage plasticity to generate immunosuppression, and how manipulation of specific macrophage populations can be used for therapeutic purposes through translational approaches.

Macrophage colony-stimulating factor plays a pivotal role in chemically induced hepatocellular carcinoma in mice

AIM

The specific purpose of this study was to investigate the role of macrophage colony-stimulating factor (M-CSF) in initiation and progression of hepatocellular carcinoma using M-CSF-deficient mice.

METHODS

M-CSF-deficient (osteopetrotic: op/op) and their littermate (LM) mice were i.p. injected with diethylnitrosamine (DEN) to induce hepatocellular carcinoma. Twenty-eight weeks after DEN administration, the tumor incidence rate and serum M-CSF levels were assessed. Furthermore, distribution of the activated macrophages and the mRNA expression of CD163 and CD204 were evaluated. Moreover, angiogenesis was analyzed in tumors. In another set of experiments, apoptosis and proliferation of the hepatocytes were examined in the acute phase after DEN administration. Isolated hepatic macrophages were cultured with or without M-CSF, and vascular endothelial growth factor (VEGF) production was assessed by enzyme-linked immunoassay.

RESULTS

Tumor incidence was significantly reduced in the op/op compared with the LM mice. Serum M-CSF levels were increased in the carcinogenesis models of the LM mice. Hepatic macrophages were found only in tumors in the op/op but in both normal liver tissue and tumors in the LM mice. In the op/op group, the mRNA expression of inflammatory cytokines was significantly lower compared with the LM mice. Furthermore, apoptosis was significantly increased in the op/op than the LM mice. Angiogenesis increased in liver tumors from the LM compared with the op/op mice. Production of VEGF was greater in the hepatic macrophages incubated with M-CSF compared with those without M-CSF.

CONCLUSION

Thus, M-CSF is involved in the progression of chemically induced hepatocarcinogenesis.

Clinicopathological significance of microRNA-214 in gastric cancer and its effect on cell biological behaviour

Accumulating evidence indicates that numerous microRNAs are involved in the tumorigenesis and progression of gastric cancer, while the clinical significance of microRNA-214 in gastric cancer is poorly understood and the exact role of microRNA-214 in gastric cancer remains obscure. In the present study, expression levels of microRNA-214 in 80 gastric carcinoma tissues, 18 nontumourous gastric tissues, and 4 types of gastric cancer cell lines were quantified by reverse transcription followed by real-time quantitative polymerase chain reaction (RT-qPCR), and the relationship between microRNA-214 expression and cliniopathological characteristics including prognosis was explored. To investigate the potential role of microRNA-214 in gastric cancer cell biological behaviour, we performed cell proliferation, apoptosis, migration and invasion assays in four gastric cancer cell lines and an immortalized gastric cell line in vitro. Our results showed that microRNA-214 was dramatically downregulated in gastric cancer tissues and gastric cancer cell lines, compared with nontumourous gastric tissues. Stepwise downregulation of microRNA-214 expression was observed among nontumourous gastric mucosa, nonmetastasis gastric cancer tissues, and metastasis gastric cancer tissues. The expression of microRNA-214 was significantly inversely correlated with lymph node metastasis and tumour size but had no correlation with the patient's prognosis. Ectopic expression of microRNA-214 could inhibit cell migration and invasion ability in SGC7901 and MKN45 gastric cancer cells. And knockdown of microRNA-214 significantly facilitated cell proliferation, migration and invasion in a cell-specific manner in MKN28, BGC823 and GES-1 cells. Colony stimulating factor 1 (CSF1) was identified as a target gene of microRNA-214. In summary, our data demonstrated that microRNA-214 is a promising novel biomarker for lymph node metastasis in patients with gastric cancer. And we identified that downregulation of microRNA-214 may regulate the proliferation, invasion and migration of gastric cancer cells by directly targeting CSF1.

The preoperative lymphocyte to monocyte ratio predicts clinical outcome in patients with stage III colon cancer

BACKGROUND

Inflammation has a critical role in the pathogenesis and progression of cancer. The lymphocyte to monocyte ratio (LMR) could be shown to be prognostic in haematologic neoplasia. In this study, we analysed the LMR with clinical outcome in stage II and III colon cancer patients.

METHODS

Three hundred and seventy-two patients with stage II and III colon cancer were included in this retrospective study. Kaplan-Meier curves and multivariate Cox-regression analyses were calculated for time to recurrence (TTR) and overall survival (OS).

RESULTS

Including all patients, the elevated preoperative LMR was significantly associated with increased TTR and OS in multivariate analysis (HR: 0.47, 95%CI: 0.29-0.76, P=0.002; HR: 0.51, 95%CI: 0.31-0.83, P=0.007; respectively). In subanalyses, the association was limited to patients with stage III (HR: 0.40, 95%CI: 0.22-0.72, P=0.002), in contrast to patients with stage II (HR: 0.40, 95%CI: 0.28-1.66, P=0.397). When the subgroup of patients with 'high-risk' LMR≤2.83 was analysed, no benefit of adjuvant 5-FU-based chemotherapy could be found (HR: 0.99; 95%CI: 0.60-1.63; P=0.953).

CONCLUSION

The LMR might be an independent prognostic marker for TTR in stage III colon cancer patients. Our results further suggest that high-risk patients based on the LMR do not benefit from adjuvant chemotherapy. Independent validation of our findings is warranted.

Proteomic approaches in biomarker discovery: new perspectives in cancer diagnostics

Despite remarkable progress in proteomic methods, including improved detection limits and sensitivity, these methods have not yet been established in routine clinical practice. The main limitations, which prevent their integration into clinics, are high cost of equipment, the need for highly trained personnel, and last, but not least, the establishment of reliable and accurate protein biomarkers or panels of protein biomarkers for detection of neoplasms. Furthermore, the complexity and heterogeneity of most solid tumours present obstacles in the discovery of specific protein signatures, which could be used for early detection of cancers, for prediction of disease outcome, and for determining the response to specific therapies. However, cancer proteome, as the end-point of pathological processes that underlie cancer development and progression, could represent an important source for the discovery of new biomarkers and molecular targets for tailored therapies.