M2 macrophages promote NSCLC metastasis by upregulating CRYAB

N6-methyladenosine modification and post-translational modification of epithelial-mesenchymal transition in colorectal cancer

Colorectal cancer is a leading cause of cancer-related mortality worldwide. Traditionally, colorectal cancer has been recognized as a disease caused by genetic mutations. However, recent studies have revealed the significant role of epigenetic alterations in the progression of colorectal cancer. Epithelial-mesenchymal transition, a critical step in cancer cell metastasis, has been found to be closely associated with the tumor microenvironment and immune factors, thereby playing a crucial role in many kinds of biological behaviors of cancers. In this review, we explored the impact of N6-methyladenosine and post-translational modifications (like methylation, acetylation, ubiquitination, SUMOylation, glycosylation, etc.) on the process of epithelial-mesenchymal transition in colorectal cancer and the epigenetic regulation for the transcription factors and pathways correlated to epithelial-mesenchymal transition. Furthermore, we emphasized that the complex regulation of epithelial-mesenchymal transition by epigenetics can provide new strategies for overcoming drug resistance and improving treatment outcomes. This review aims to provide important scientific evidence for the prevention and treatment of colorectal cancer based on epigenetic modifications.

The Biological Role of Macrophage in Lung and Its Implications in Lung Cancer Immunotherapy

The lungs are the largest surface of the body and the most important organ in the respiratory system, which are constantly exposed to the external environment. Tissue Resident Macrophages in lung constitutes the important defense against external pathogens. Macrophages connects the innate and adaptive immune system, and also plays important roles in carcinogenesis and cancer immunotherapy. Lung cancer is the leading cause of cancer-related death worldwide, with an overall five-year survival rate of only 21%. Macrophages that infiltrate or aggregate in lung tumor microenvironment are defined as tumor-associated macrophages (TAMs). TAMs are the main components of immune cells in the lung tumor microenvironment. The differentiation and maturation process of TAMs can be roughly divided into two different types: classical activation pathway produces M1 tumor-associated macrophages, and bypass activation pathway produces M2 tumor-associated macrophages. Studies have found that TAMs are related to tumor invasion, metastasis, and treatment resistance, and show potential as a new target for tumor immunotherapy. Therefore, the biological function of macrophages in lung and the role of TAMs in the occurrence, development, and treatment of lung cancer are discussed in this paper.

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

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

IL6-STAT3-C/EBPβ-IL6 positive feedback loop in tumor-associated macrophages promotes the EMT and metastasis of lung adenocarcinoma

BACKGROUND

Lung cancer is one of the most common tumors in the world, and metastasis is one of the major causes of tumor-related death in lung cancer patients. Tumor-associated macrophages (TAMs) are a major component of the tumor microenvironment (TME) and are frequently associated with tumor metastasis in human cancers. However, the regulatory mechanisms of TAMs in lung cancer metastasis remain unclear.

METHODS

Single-cell sequencing analysis of lung cancer and normal tissues from public databases and from 14 patients who underwent surgery at Zhongshan Hospital was performed. In vitro co-culture experiments were performed to evaluate the effects of TAMs on lung cancer migration and invasion. Changes in the expression of IL-6, STAT3, C/EBPΒ, and EMT pathway were verified using RT-qPCR, western blotting, and immunofluorescence. Dual luciferase reporter assays and ChIP were used to reveal potential regulatory sites on the transcription factor sets. In addition, the effects of TAMs on lung cancer progression and metastasis were confirmed by in vivo models.

RESULTS

TAM infiltration is associated with tumor progression and poor prognosis. IL-6 secreted by TAMs can activate the JAK2/STAT3 pathway through autocrine secretion, and STAT3 acts as a transcription factor to activate the expression of C/EBPβ, which further promotes the transcription and expression of IL-6, forming positive feedback loops for IL6-STAT3-C/EBPβ-IL6 in TAMs. IL-6 secreted by TAMs promotes lung cancer progression and metastasis in vivo and in vitro by activating the EMT pathway, which can be attenuated by the use of JAK2/STAT3 pathway inhibitors or IL-6 monoclonal antibodies.

CONCLUSIONS

Our data suggest that TAMs promote IL-6 expression by forming an IL6-STAT3-C/EBPβ-IL6 positive feedback loop. Released IL-6 can induce the EMT pathway in lung cancer to enhance migration, invasion, and metastasis. The use of IL-6-neutralizing antibody can partially counteract the promotion of LUAD by TAMs. A novel mechanism of macrophage-promoted tumor progression was revealed, and the IL6-STAT3-C/EBPβ-IL6 signaling cascade may be a potential therapeutic target against lung cancer.

The role of tumor-associated macrophages in lung cancer: From mechanism to small molecule therapy

Tumor-associated macrophages (TAMs) are the main component of tumor-infiltrating immune cells in the lung tumor microenvironment. TAMs recruited to the lung cancer can create a suitable microenvironment for the growth and metastasis of lung cancer by secreting tumor promoting factors and interfering with the function of T cells. Currently, numerous studies have reported that small molecular drugs affect lung cancer progression by selectively targeting TAMs. The main ways include blocking the recruitment of monocytes or eliminating existing TAMs in tumor tissue, reprogramming TAMs into pro-inflammatory M1 macrophages or inhibiting M2 polarization of macrophages, interrupting the interaction between tumor cells and macrophages, and modulating immune function. Signaling pathways or cytokines such as CCL8, CCL2/CCR2, CSF-1/CSF-1R, STAT3, STAT6, MMPs, Caspase-8, AMPK α1, TLR3, CD47/SIRPα, have been reported to be involved in this process. Based on summarizing the role and mechanisms of TAMs in lung cancer progression, this paper particularly focuses on systematically reviewing the effects and mechanisms of small molecule drugs on lung cancer TAMs, and classified the small molecular drugs according to the way they affect TAMs. The study aims to provide new perspectives and potential therapeutic drugs for targeted macrophages treatment in lung cancer, which is of great significance and will provide more options for immunotherapy of lung cancer.

Circular RNA circATP9A promotes non-small cell lung cancer progression by interacting with HuR and by promoting extracellular vesicles-mediated macrophage M2 polarization

BACKGROUND

CircRNA is recognized for its significant regulatory function across various cancers. However, its regulatory role in non-small cell lung cancer (NSCLC) is still largely uncharted.

METHODS

Analysis based on public databases is completed using R software. circATP9A was identified by two circRNA datasets of NSCLC from the Gene Expression Omnibus database. To examine the impact of circATP9A on the phenotype of NSCLC, we conducted both in vitro and in vivo functional experiments. The mRNA and protein levels of specific molecules were determined through quantitative real-time PCR and western blot assays. RNA pulldown and RNA immunoprecipitation assays were performed to verify the interaction between RNA and protein. The functional role of extracellular vesicles (EVs)-circATP9A on tumor-associated macrophage (TAM) polarization was assessed using co-culture system and cell flow cytometry.

RESULTS

Here, we elucidates the functional role of circATP9A in NSCLC. We demonstrated that circATP9A can foster the progression of NSCLC through in vivo and in vitro experiments. From a mechanistic standpoint, circATP9A can interact with the HuR protein to form an RNA-protein complex, subsequently amplifying the mRNA and protein levels of the target gene NUCKS1. Further, the PI3K/AKT/mTOR signaling was identified as the downstream pathways of circATP9A/HuR/NUCKS1 axis. More notably, hnRNPA2B1 can mediate the incorporation of circATP9A into EVs. Subsequently, these EVs containing circATP9A induce the M2 phenotype of TAMs, thereby facilitating NSCLC development.

CONCLUSIONS

Our discoveries indicate that circATP9A could serve as a promising diagnostic indicator and a therapeutic target for NSCLC.

The cross-talk between macrophages and tumor cells as a target for cancer treatment

Macrophages represent an important component of the innate immune system. Under physiological conditions, macrophages, which are essential phagocytes, maintain a proinflammatory response and repair damaged tissue. However, these processes are often impaired upon tumorigenesis, in which tumor-associated macrophages (TAMs) protect and support the growth, proliferation, and invasion of tumor cells and promote suppression of antitumor immunity. TAM abundance is closely associated with poor outcome of cancer, with impediment of chemotherapy effectiveness and ultimately a dismal therapy response and inferior overall survival. Thus, cross-talk between cancer cells and TAMs is an important target for immune checkpoint therapies and metabolic interventions, spurring interest in it as a therapeutic vulnerability for both hematological cancers and solid tumors. Furthermore, targeting of this cross-talk has emerged as a promising strategy for cancer treatment with the antibody against CD47 protein, a critical macrophage checkpoint recognized as the "don't eat me" signal, as well as other metabolism-focused strategies. Therapies targeting CD47 constitute an important milestone in the advancement of anticancer research and have had promising effects on not only phagocytosis activation but also innate and adaptive immune system activation, effectively counteracting tumor cells' evasion of therapy as shown in the context of myeloid cancers. Targeting of CD47 signaling is only one of several possibilities to reverse the immunosuppressive and tumor-protective tumor environment with the aim of enhancing the antitumor response. Several preclinical studies identified signaling pathways that regulate the recruitment, polarization, or metabolism of TAMs. In this review, we summarize the current understanding of the role of macrophages in cancer progression and the mechanisms by which they communicate with tumor cells. Additionally, we dissect various therapeutic strategies developed to target macrophage-tumor cell cross-talk, including modulation of macrophage polarization, blockade of signaling pathways, and disruption of physical interactions between leukemia cells and macrophages. Finally, we highlight the challenges associated with tumor hypoxia and acidosis as barriers to effective cancer therapy and discuss opportunities for future research in this field.

Integrative Analysis of Single-Cell and Bulk RNA Sequencing Reveals Prognostic Characteristics of Macrophage Polarization-Related Genes in Lung Adenocarcinoma

Background

Lung adenocarcinoma (LUAD) is a group of cancers with poor prognosis. The combination of single-cell RNA sequencing (scRNA-seq) and bulk RNA sequencing (RNA-seq) can identify important genes involved in cancer development and progression from a broader perspective.

Methods

The scRNA-seq data and bulk RNA-seq data of LUAD were downloaded from the Gene Expression Omnibus (GEO) database and the Cancer Genome Atlas (TCGA) database. Analyzing scRNA-seq for core cells in the GSE131907 dataset, and the uniform manifold approximation and projection (UMAP) was used for dimensionality reduction and cluster identification. Macrophage polarization-associated subtypes were acquired from the TCGA-LUAD dataset after analysis, followed by further identification of differentially expressed genes (DEGs) in the TCGA-LUAD dataset (normal/LUAD tissue samples, two subtypes). Venn diagrams were utilized to visualize differentially expressed and highly variable macrophage polarization-related genes. Subsequently, a prognostic risk model for LUAD patients was constructed by univariate Cox and Least Absolute Shrinkage and Selection Operator (LASSO), and the model was investigated for stability in the external data GSE72094. After analyzing the correlation between the trait genes and significantly mutated genes, the immune infiltration between the high/low-risk groups was then examined. The Monocle package was applied to analyze the pseudo-temporal trajectory analysis of different cell clusters in macrophage clusters. Subsequently, cell clusters of data macrophages were selected as key cell clusters to explore the role of characteristic genes in different cell populations and to identify transcription factors (TFs) that affect signature genes. Finally, qPCR were employed to validate the expression levels of prognosis signature genes in LUAD.

Results

424 macrophage highly variable genes, 3920 DEGs, and 9561 DEGs were obtained from macrophage clusters, the macrophage polarization-related subtypes, and normal/LUAD tissue samples, respectively. Twenty-eight differentially expressed and highly mutated MPRGs were obtained. A prognostic risk model with 7 DE-MPRGs (RGS13, ADRB2, DDIT4, MS4A2, ALDH2, CTSH, and PKM) was constructed. This prognostic model still has a good prediction effect in the GSE72094 dataset. ZNF536 and DNAH9 were mutated in the low-risk group, while COL11A1 was mutated in the high-risk group, and they were highly correlated with the characteristic genes. A total of 11 immune cells were significantly different in the high/low-risk groups. Five cell types were again identified in the macrophage cluster, and then NK cells: CD56hiCD62L+ differentiated earlier and were present mainly on 2 branches. While macrophages were present on 2 branches and differentiated later. It was found that the expression levels of BCLAF1 and MAX were higher in cluster 1, which might be the TFs affecting the expression of the characteristic genes. Moreover, qPCR confirmed that the expression of the prognosis genes was generally consistent with the results of the bioinformatic analysis.

Conclusion

Seven MPRGs (RGS13, ADRB2, DDIT4, MS4A2, ALDH2, CTSH, and PKM) were identified as prognostic genes for LUAD and revealed the mechanisms of MPRGs at the single-cell level.

A novel model based on disulfidptosis-related genes to predict prognosis and therapy of bladder urothelial carcinoma

PURPOSE

Disulfidptosis is a novel type of cell death induced by disulphide stress that depends on the accumulation of cystine disulphide, causing cytotoxicity and triggering cell death. However, the direct prognostic effect and regulatory mechanism of disulfidptosis-related genes in bladder urothelial carcinoma (BLCA) remain unclear.

METHODS

To explore the role of 10 disulfidptosis-related genes, the multiomic data of 10 genes were comprehensively analysed. Next, based on seven disulfidptosis-related differentially expressed genes, a novel disulfidptosis-related gene score was developed to help predict the prognosis of BLCA. Immunohistochemistry, EDU, Real-time PCR and western blot were used to verify the model.

RESULTS

Significant functional differences were found between the high- and low-risk score groups, and samples with a higher risk score were more malignant. Furthermore, the tumour exclusion and Tumour Immune Dysfunction and Exclusion scores of the high-risk score group were higher than those of the low-risk score group. The risk score was positively correlated with the expression of immune checkpoints. Drug sensitivity analyses revealed that the low-risk score group had a higher sensitivity to cisplatin, doxorubicin, docetaxel and gemcitabine than the high-risk score group. Moreover, the expression of the TM4SF1 was positively correlated with the malignancy degree of BLCA, and the proliferation ability of BLCA cells was reduced after knockdown TM4SF1.

CONCLUSION

The present study results suggest that disulfidptosis-related genes influence the prognosis of BLCA through their involvement in immune cell infiltration. Thus, these findings indicate the role of disulfidptosis in BLCA and its potential regulatory mechanisms.

Comprehensive analyses for the coagulation and macrophage-related genes to reveal their joint roles in the prognosis and immunotherapy of lung adenocarcinoma patients

Purpose

This study aims to explore novel biomarkers related to the coagulation process and tumor-associated macrophage (TAM) infiltration in lung adenocarcinoma (LUAD).

Methods

The macrophage M2-related genes were obtained by Weighted Gene Co-expression Network Analysis (WGCNA) in bulk RNA-seq data, while the TAM marker genes were identified by analyzing the scRNA-seq data, and the coagulation-associated genes were obtained from MSigDB and KEGG databases. Survival analysis was performed for the intersectional genes. A risk score model was subsequently constructed based on the survival-related genes for prognosis prediction and validated in external datasets.

Results

In total, 33 coagulation and macrophage-related (COMAR) genes were obtained, 19 of which were selected for the risk score model construction. Finally, 10 survival-associated genes (APOE, ARRB2, C1QB, F13A1, FCGR2A, FYN, ITGB2, MMP9, OLR1, and VSIG4) were involved in the COMAR risk score model. According to the risk score, patients were equally divided into low- and high-risk groups, and the prognosis of patients in the high-risk group was significantly worse than that in the low-risk group. The ROC curve indicated that the risk score model had high sensitivity and specificity, which was validated in multiple external datasets. Moreover, the model also had high efficacy in predicting the clinical outcomes of LUAD patients who received anti-PD-1/PD-L1 immunotherapy.

Conclusion

The COMAR risk score model constructed in this study has excellent predictive value for the prognosis and immunotherapeutic clinical outcomes of patients with LUAD, which provides potential biomarkers for the treatment and prognostic prediction.

Integrated analysis of single-cell and bulk RNA-sequencing reveals the poor prognostic value of ABCA1 in gastric adenocarcinoma

PURPOSE

ATP-binding cassette A1 (ABCA1) is a potential prognostic marker for various tumor types. However, the biological effects and prognostic value of ABCA1 in gastric adenocarcinoma (GAC) remain unknown.

METHODS

GAC-associated single-cell RNA and bulk RNA-sequencing (bulk-seq) data were obtained from the Gene Expression Omnibus and The Cancer Genome Atlas databases, respectively. The differential expression of ABCA1 between GAC and normal gastric tissues was analyzed based on the bulk-seq data. Additionally, the relationship between ABCA1 expression and various clinicopathological features was explored. Furthermore, Kaplan-Meier survival and Cox regression analyses were performed to establish the prognostic value of ABCA1. The relationships between ABCA1 expression and anti-tumor drug sensitivity and immune checkpoints were also explored. Finally, the biological functions of ABCA1 were evaluated at the single-cell level, and in vitro studies were performed to assess the effects of ABCA1 on GAC cell proliferation and invasion.

RESULTS

ABCA1 expression is significantly elevated in GAC samples compared with that in normal gastric tissues. Clinical features and survival analysis revealed that high ABCA1 expression is associated with poor clinical phenotypes and prognosis, whereas Cox analysis identified ABCA1 as an independent risk factor for patients with GAC. Furthermore, high ABCA1 expression suppresses sensitivity to various chemotherapeutic drugs, including cisplatin and mitomycin, while upregulating immune checkpoints. ABCA1-overexpressing macrophages are associated with adverse clinical phenotypes in GAC and express unique ligand-receptor pairs that drive GAC progression. In vitro, ABCA1-knockdown GAC cells exhibit significantly inhibited proliferative and invasive properties.

CONCLUSION

High ABCA1 expression promotes an adverse immune microenvironment and low survival rates in patients with GAC. Furthermore, ABCA1 and ABCA1-producing macrophages may serve as novel molecular targets in GAC treatment.

Dendritic Cell Vaccination in Non-Small Cell Lung Cancer: Remodeling the Tumor Immune Microenvironment

Non-small-cell lung cancer (NSCLC) remains one of the leading causes of death worldwide. While NSCLCs possess antigens that can potentially elicit T cell responses, defective tumor antigen presentation and T cell activation hinder host anti-tumor immune responses. The NSCLC tumor microenvironment (TME) is composed of cellular and soluble mediators that can promote or combat tumor growth. The composition of the TME plays a critical role in promoting tumorigenesis and dictating anti-tumor immune responses to immunotherapy. Dendritic cells (DCs) are critical immune cells that activate anti-tumor T cell responses and sustain effector responses. DC vaccination is a promising cellular immunotherapy that has the potential to facilitate anti-tumor immune responses and transform the composition of the NSCLC TME via tumor antigen presentation and cell-cell communication. Here, we will review the features of the NSCLC TME with an emphasis on the immune cell phenotypes that directly interact with DCs. Additionally, we will summarize the major preclinical and clinical approaches for DC vaccine generation and examine how effective DC vaccination can transform the NSCLC TME toward a state of sustained anti-tumor immune signaling.

MicroRNA-155 and cancer metastasis: Regulation of invasion, migration, and epithelial-to-mesenchymal transition

Among the leading causes of death globally has been cancer. Nearly 90% of all cancer-related fatalities are attributed to metastasis, which is the growing of additional malignant growths out of the original cancer origin. Therefore, a significant clinical need for a deeper comprehension of metastasis exists. Beginning investigations are being made on the function of microRNAs (miRNAs) in the metastatic process. Tiny non-coding RNAs called miRNAs have a crucial part in controlling the spread of cancer. Some miRNAs regulate migration, invasion, colonization, cancer stem cells' properties, the epithelial-mesenchymal transition (EMT), and the microenvironment, among other processes, to either promote or prevent metastasis. One of the most well-conserved and versatile miRNAs, miR-155 is primarily distinguished by overexpression in a variety of illnesses, including malignant tumors. It has been discovered that altered miR-155 expression is connected to a number of physiological and pathological processes, including metastasis. As a result, miR-155-mediated signaling pathways were identified as possible cancer molecular therapy targets. The current research on miR-155, which is important in controlling cancer cells' invasion, and metastasis as well as migration, will be summarized in the current work. The crucial significance of the lncRNA/circRNA-miR-155-mRNA network as a crucial regulator of carcinogenesis and a player in the regulation of signaling pathways or related genes implicated in cancer metastasis will be covered in the final section. These might provide light on the creation of fresh treatment plans for controlling cancer metastasis.

Proteolytically degradable PEG hydrogel matrix mimicking tumor immune microenvironment for 3D co-culture of lung adenocarcinoma cells and macrophages

Tumor-associated macrophages and monocytes are the major stromal cell types found in the tumor immune microenvironment (TIME), which modulates tumor progression, invasion, and chemoresistance. To address the need for an in vitro three-dimensional tumor model for understanding the complex cellular interactions within the TIME, we propose a TIME-mimetic co-culture matrix composed of photo-crosslinked poly(ethylene glycol) hydrogels mimicking the characteristics of the tumor and stroma. Desmoplasia-mimetic microgels encapsulating lung adenocarcinoma cells (A549) were embedded with monocyte- or macrophage-type U937 cells in normal stroma-mimetic hydrogel, increasing the proximity between the two cell types. By modulating the proteolytic degradability of the hydrogels, we could separate different cell types with high purities for use in orthogonal assays. In addition, we demonstrated that U937 cells had distinct influences on A549 cell death depending on their activation states (i.e. monocyte, M0, or M1 phenotype). M1 macrophages suppressed tumor growth and increased the susceptibility of A549 cells to cisplatin. In contrast, monocytes upregulated cancer stem cell markers (OCT4, SOX2, and SHH) of A549 cells, showing M2-like features, such as downregulated expression of proinflammatory markers (IL6 and TNFα). These findings suggest that this co-culture system is potentially used for investigation of heterotypic cellular interactions in the TIME.

Exosomal miR-21 determines lung-to-brain metastasis specificity through the DGKB/ERK axis within the tumor microenvironment

BACKGROUND

Brain metastasis affects 20-40 % of lung cancer patients, severely diminishing their quality of life. This research focuses on miR-21, overexpressed in these patients and inversely associated with DGKB in the ERK/STAT3 pathway, suggesting a dysregulated pathway with therapeutic potential.

AIMS

The objective was to investigate miR-21's role in lung cancer patients with brain metastases and whether targeting this pathway could improve treatment outcomes. We also examined the miR-21 content in tumor spheres-derived extracellular vesicles (EVs) and their influence on ERK/STAT3 signaling and metastasis.

MATERIALS AND METHODS

Tumor spheres were created from metastatic lung cancer cells. We studied miR-21 levels in these spheres, their impact on macrophage polarization, and the transition of nonmetastatic lung cancer cells. Furthermore, we analyzed miR-21 content in EVs derived from these spheres and their effect on ERK/STAT3 signaling and metastasis potential.

KEY FINDINGS

We found tumor spheres had high miR-21 levels, promoting macrophage polarization and, epithelial-mesenchymal transition. These spheres-derived EVs, enriched with miR-21, accelerated ERK/STAT3 signaling and metastasis. Silencing miR-21 and inhibiting ERK signaling with ulixertinib notably mitigated these effects. Moreover, ulixertinib reduced brain metastasis incidence and increased survival in a mouse model and led to reduced tumor sphere generation and miR-21 levels in EVs.

SIGNIFICANCE

Our study highlights the exacerbation of lung-to-brain metastasis via miR-21-rich EV secretion. This underlines the therapeutic promise of targeting the miR-21/ERK/STAT3 pathway with ulixertinib for managing brain metastasis from lung cancer.

Tumor suppressor p53 mediates interleukin-6 expression to enable cancer cell evasion of genotoxic stress

The tumor suppressor p53 primarily functions as a mediator of DNA damage-induced cell death, thereby contributing to the efficacy of genotoxic anticancer therapeutics. Here, we show, on the contrary, that cancer cells can employ genotoxic stress-induced p53 to acquire treatment resistance through the production of the pleiotropic cytokine interleukin (IL)-6. Mechanistically, DNA damage, either repairable or irreparable, activates p53 and stimulates Caspase-2-mediated cleavage of its negative regulator mouse double minute 2 (MDM2) creating a positive feedback loop that leads to elevated p53 protein accumulation. p53 transcriptionally controls the major adenosine triphosphate (ATP) release channel pannexin 1 (Panx1), which directs IL-6 induction via a mechanism dependent on the extracellular ATP-activated purinergic P2 receptors as well as their downstream intracellular calcium (iCa2+)/PI3K/Akt/NF-ĸB signaling pathway. Thus, p53 silencing impairs Panx1 and IL-6 expression and renders cancer cells sensitive to genotoxic stress. Moreover, we confirm that IL-6 hampers the effectiveness of genotoxic anticancer agents by mitigating DNA damage, driving the expression of anti-apoptotic Bcl-2 family genes, and maintaining the migratory and invasive properties of cancer cells. Analysis of patient survival and relevant factors in lung cancer and pan-cancer cohorts supports the prognostic and clinical values of Panx1 and IL-6. Notably, IL-6 secreted by cancer cells during genotoxic treatments promotes the polarization of monocytic THP-1-derived macrophages into an alternative (M2-like) phenotype that exhibits impaired anti-survival activities but enhanced pro-metastatic effects on cancer cells as compared to nonpolarized macrophages. Our study reveals the precise mechanism for genotoxic-induced IL-6 and suggests that targeting p53-mediated IL-6 may improve the responsiveness of cancer cells to genotoxic anticancer therapy.

Micro-engineering and nano-engineering approaches to investigate tumour ecosystems

The interactions among tumour cells, the tumour microenvironment (TME) and non-tumour tissues are of interest to many cancer researchers. Micro-engineering approaches and nanotechnologies are under extensive exploration for modelling these interactions and measuring them in situ and in vivo to investigate therapeutic vulnerabilities in cancer and extend a systemic view of tumour ecosystems. Here we highlight the greatest opportunities for improving the understanding of tumour ecosystems using microfluidic devices, bioprinting or organ-on-a-chip approaches. We also discuss the potential of nanosensors that can transmit information from within the TME or elsewhere in the body to address scientific and clinical questions about changes in chemical gradients, enzymatic activities, metabolic and immune profiles of the TME and circulating analytes. This Review aims to connect the cancer biology and engineering communities, presenting biomedical technologies that may expand the methodologies of the former, while inspiring the latter to develop approaches for interrogating cancer ecosystems.

Identification of cancer stemness and M2 macrophage-associated biomarkers in lung adenocarcinoma

Objective

Cancer stemness and M2 macrophages are intimately linked to the prognosis of lung adenocarcinoma (LUAD). For this reason, this investigation sought to identify the key genes relevant to cancer stemness and M2 macrophages, explore the relationship between these genes and clinical characteristics, and determine the potential mechanism.

Methods

LUAD transcriptomic data was analyzed from The Cancer Genome Atlas (TCGA) as well as the Gene Expression Omnibus databases. Differential expression analysis was performed to discern abnormally expressed genes between LUAD and control samples in TCGA cohort. The Cell type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) algorithm was applied to determine varyingly infiltrated immune cells in LUAD compared with the control samples in TCGA cohort. Weighted correlation network analysis (WGCNA) was performed to identify genes associated with mRNA expression-based stemness index (mRNAsi) and M2 macrophages. Least absolute shrinkage and selection operator (LASSO), RandomForest (RF) and support vector machine-recursive feature elimination (SVM-RFE) machine learning methods were conducted to detect gene signatures. Global survival evaluation (Kaplan-Meier curve) was applied to investigate the relationship between gene signatures and the survival time of LUAD patients. Receiver operating characteristic (ROC) curves were produced to define biomarkers relevant to diagnosis. Gene Set Enrichment Analysis (GSEA) was performed to probe the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to diagnostic biomarkers. The public single-cell dataset of LUAD (GSE123902) was used to investigate the expression differences of diagnostic biomarkers in various cell types in LUAD. Real-time quantitative PCR (qRT-PCR) was performed to confirm key genes in lung adenocarcinoma cells.

Results

A total of 5,410 differentialy expressed genes (DEGs) as well as 15 differentially infiltrated immune cells were identified between LUAD and control sepcimens in TCGA cohort. Thirty-seven DEGs were associated with both M2 macrophages and mRNAsi according to the WGCNA analysis. Sixteen common gene signatures were obtained using three diverse algorithms. CBFA2T3, DENND3 and FCAMR were correlated to overall and disease-free survival of LUAD patients. ROC curves revealed that CBFA2T3 and DENND3 expression accurately classified LUAD and control samples. The results of single cell related analysis showed that two diagnostic biomarkers expressions were differed between the different tissue sources in M2-like macrophages. QRT-PCR demonstrated the mRNA expressions of CBFA2T3 and DENND3 were upregulated in lung adenocarcinoma cells A549 and H2122.

Conclusion

Our study identified CBFA2T3 and DENND3 as key genes associated with mRNAsi and M2 macrophages in LUAD and investigated the potential molecular mechanisms underlying this relationship.

TFEB: a double-edged sword for tumor metastasis

Transcription factor EB, a member of the microphthalmia-associated transcription factor (MiTF/TFE) family, is a master regulator of autophagy, lysosome biogenesis, and TAMs. Metastasis is one of the main reasons for the failure of tumor therapy. Studies on the relationship between TFEB and tumor metastasis are contradictory. On the positive side, TFEB mainly affects tumor cell metastasis via five aspects, including autophagy, epithelial-mesenchymal transition (EMT), lysosomal biogenesis, lipid metabolism, and oncogenic signaling pathways; on the negative side, TFEB mainly affects tumor cell metastasis in two aspects, including tumor-associated macrophages (TAMs) and EMT. In this review, we described the detailed mechanism of TFEB-mediated regulation of metastasis. In addition, we also described the activation and inactivation of TFEB in several aspects, including the mTORC1 and Rag GTPase systems, ERK2, and AKT. However, the exact process by which TFEB regulates tumor metastasis remains unclear in some pathways, which requires further studies.

Clearance of senescent macrophages ameliorates tumorigenesis in KRAS-driven lung cancer

The accumulation of senescent cells in the tumor microenvironment can drive tumorigenesis in a paracrine manner through the senescence-associated secretory phenotype (SASP). Using a new p16-FDR mouse line, we show that macrophages and endothelial cells are the predominant senescent cell types in murine KRAS-driven lung tumors. Through single cell transcriptomics, we identify a population of tumor-associated macrophages that express a unique array of pro-tumorigenic SASP factors and surface proteins and are also present in normal aged lungs. Genetic or senolytic ablation of senescent cells, or macrophage depletion, result in a significant decrease in tumor burden and increased survival in KRAS-driven lung cancer models. Moreover, we reveal the presence of macrophages with senescent features in human lung pre-malignant lesions, but not in adenocarcinomas. Taken together, our results have uncovered the important role of senescent macrophages in the initiation and progression of lung cancer, highlighting potential therapeutic avenues and cancer preventative strategies.

Macrophages in immunoregulation and therapeutics

Macrophages exist in various tissues, several body cavities, and around mucosal surfaces and are a vital part of the innate immune system for host defense against many pathogens and cancers. Macrophages possess binary M1/M2 macrophage polarization settings, which perform a central role in an array of immune tasks via intrinsic signal cascades and, therefore, must be precisely regulated. Many crucial questions about macrophage signaling and immune modulation are yet to be uncovered. In addition, the clinical importance of tumor-associated macrophages is becoming more widely recognized as significant progress has been made in understanding their biology. Moreover, they are an integral part of the tumor microenvironment, playing a part in the regulation of a wide variety of processes including angiogenesis, extracellular matrix transformation, cancer cell proliferation, metastasis, immunosuppression, and resistance to chemotherapeutic and checkpoint blockade immunotherapies. Herein, we discuss immune regulation in macrophage polarization and signaling, mechanical stresses and modulation, metabolic signaling pathways, mitochondrial and transcriptional, and epigenetic regulation. Furthermore, we have broadly extended the understanding of macrophages in extracellular traps and the essential roles of autophagy and aging in regulating macrophage functions. Moreover, we discussed recent advances in macrophages-mediated immune regulation of autoimmune diseases and tumorigenesis. Lastly, we discussed targeted macrophage therapy to portray prospective targets for therapeutic strategies in health and diseases.

Macrophage Polarization: An Important Candidate Regulator for Lung Diseases

Macrophages are crucial components of the immune system and play a critical role in the initial defense against pathogens. They are highly heterogeneous and plastic and can be polarized into classically activated macrophages (M1) or selectively activated macrophages (M2) in response to local microenvironments. Macrophage polarization involves the regulation of multiple signaling pathways and transcription factors. Here, we focused on the origin of macrophages, the phenotype and polarization of macrophages, as well as the signaling pathways associated with macrophage polarization. We also highlighted the role of macrophage polarization in lung diseases. We intend to enhance the understanding of the functions and immunomodulatory features of macrophages. Based on our review, we believe that targeting macrophage phenotypes is a viable and promising strategy for treating lung diseases.

Tumor Suppressor miR-613 Alleviates Non-Small Cell Lung Cancer Cell via Repressing M2 Macrophage Polarization

Background

Non-small cell lung cancer (NSCLC) is a crucial crux of cancer-related death, and M2 macrophage polarization facilitates NSCLC development. MicroRNA-613 (miR-613) is a tumor suppressor. This research aimed to clarify the miR-613 function in NSCLC and its impact on M2 macrophage polarization. Methods. miR-613 expressions in NSCLC tissues and cells were evaluated using quantitative real-time PCR. For miR-613 function in NSCLC, cell proliferation analysis, cell counting kit-8, flow cytometry, western blot, transwell, and wound-healing were conducted. Meanwhile, the miR-613 impact on M2 macrophage polarization was assessed by the NSCLC models. Results. miR-613 was lessened in NSCLC cells and tissues. It was corroborated that miR-613 overexpression retrained NSCLC cell proliferation, invasion, and migration but facilitated cell apoptosis. Moreover, miR-613 overexpression restrained NSCLC development by repressing M2 macrophage polarization.

Conclusion

Tumor suppressor miR-613 ameliorated NSCLC by restraining M2 macrophage polarization.

Immunotherapeutic targets in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is one of the most common types of cancer in the world and has a 5-year survival rate of ~20%. Immunotherapies have shown promising results leading to durable responses, however, they are only effective for a subset of patients. To determine the best therapeutic approach, a thorough and in-depth profiling of the tumour microenvironment (TME) is required. The TME is a complex network of cell types that form an interconnected network, promoting tumour cell initiation, growth and dissemination. The stroma, immune cells and endothelial cells that comprise the TME generate a plethora of cytotoxic or cytoprotective signalling pathways. In this review, we discuss immunotherapeutic targets in NSCLC tumours and how the TME may influence patients' response to immunotherapy.

M2 macrophages-derived exosomal miR-3917 promotes the progression of lung cancer via targeting GRK6

Macrophages in the tumor microenvironment (TME) can serve as potential targets for therapeutic intervention. The aim of this study was to investigate the molecular mechanism by which M2 macrophage-derived exosomes (M2-Ex) affect lung cancer progression through miRNA transport. The THP-1 cells were differentiated into M0 and M2 macrophages. M2-Ex were isolated and identified by transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). Cancer tissues and adjacent tissues of non-small-cell lung cancer (NSCLC) patients were collected. H1299 and A549 cells were co-cultured with M2-Ex. Subcutaneous xenograft mouse model was established. miR-3917 is highly expressed in lung cancer tissues and M2-Ex. Interference of miR-3917 in M2-Ex inhibits H1299 cell proliferation, migration and invasion, while overexpression of miR-3917 had the opposite effect in A549 cells. M2-Ex promote tumor growth by delivering miR-3917 in vivo. miR-3917 could target G protein-coupled receptor kinase 6 (GRK6), and interference of miR-3917 in M2-Ex inhibits H1299 cells proliferation, migration and invasion by up-regulating GRK6 level, while overexpression of miR-3917 had the opposite effect in A549 cells. M2-Ex can transfer miR-3917 into lung cancer cells and promote lung cancer progression, providing theoretical basis for the diagnosis and effective treatment of lung cancer.

The role of CRYAB in tumor prognosis and immune infiltration: A Pan-cancer analysis

Purpose

There is evidence that the Crystallin Alpha B (CRYAB) gene is involved in the regulation of the tumor microenvironment and influences tumor prognosis in some cancers. However, the role of CRYAB gene in prognosis and immunology in pan-cancer is still unclear.

Methods

In this study, we analyzed the transcriptional profiles and survival data of cancer patients from The Cancer Genome Atlas (TCGA) database. CRYAB gene and its relationships with pan-cancer were analyzed using R packages, TIMER2.0, GEPIA2, Sangerbox, UALCAN, cBioPortal, ESTIMATE algorithm, and STRING. Besides, real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) was utilized to detect CRYAB expression in KIRC and a human KIRC cell line (Caki-1).

Results

We found that CRYAB expression was different in tumors and adjacent tumors in human cancers, affecting patients' prognosis in 15 cancer types. Additionally, CRYAB expression significantly correlated with tumor microenvironment (TME), immune checkpoints (ICP), tumor mutational burden (TMB), and microsatellite instability (MSI) in human cancers. Besides, CRYAB expression was positively associated with the immune infiltration of cancer-associated fibroblasts (CAFs) and endothelial cells in most human cancers. Based on enrichment analysis, the most prevalent CRYAB gene mechanism in malignant tumors may be through anti-apoptotic activity. Moreover, some FDA-approved drugs were found to be associated with CRYAB and might be potential cancer therapeutic candidates.

Conclusions

CRYAB is a crucial component of the TME and influences immune cell infiltration, making it a promising biomarker to assess immune infiltration and prognosis in many malignancies.

Macrophage scavenger receptors: Tumor support and tumor inhibition

Tumor-associated macrophages (TAMs) are a heterogeneous population of myeloid cells that constitute up to 50% of the cell mass of human tumors. TAMs interact with the components of the tumor microenvironment (TME) by using scavenger receptors (SRs), a large superfamily of multifunctional receptors that recognize, internalize and transport to the endosomal/lysosomal pathway apoptotic cells, cytokines, matrix molecules, lipid modified lipoproteins and other unwanted-self ligands. In our review, we summarized state-of-the art for the role of macrophage scavenger receptors in tumor development and their significance as cancer biomarkers. In this review we focused on functional activity of TAM-expressing SRs in animal models and in patients, and summarized the data for different human cancer types about the prognostic significance of TAM-expressed SRs. We discussed the role of SRs in the regulation of cancer cell biology, cell-cell and cell-matrix interaction in TME, immune status in TME, angiogenesis, and intratumoral metabolism. Targeting of tumor-promoting SRs can be a promising therapeutic approach in anti-cancer therapy. In our review we provide evidence for both tumor supporting and tumor inhibiting functions of scavenger receptors expressed on TAMs. We focused on the key differences in the prognostic and functional roles of SRs that are specific for cancer types. We highlighted perspectives for inhibition of tumor-promoting SRs in anti-cancer therapy.

The role of macrophages in non-small cell lung cancer and advancements in 3D co-cultures

Lung cancer (LC) is the leading cause of cancer-related deaths worldwide. Traditional therapeutic approaches such as chemotherapy or radiotherapy have provided only a marginal improvement in the treatment of lung carcinomas. Inhibitors targeting specific genetic aberrations present in non-small cell lung cancer (NSCLC), the most common subtype (85%), have improved the prognostic outlook, but due to the complexity of the LC mutational spectrum, only a fraction of patients benefit from these targeted molecular therapies. More recently, the realization that the immune infiltrate surrounding solid tumors can foster tumor-promoting inflammation has led to the development and implementation of anticancer immunotherapies in the clinic. In NSCLC, one of the most abundant leukocyte infiltrates is macrophages. These highly plastic phagocytes, which are part of the cellular repertoire of the innate immunity, can have a pivotal role in early NSCLC establishment, malignant progression, and tumor invasion. Emerging macrophage-targeting therapies have been focused on the re-differentiation of the macrophages toward an antitumorigenic phenotype, depletion of tumor-promoting macrophage subtypes, or combination therapies combining traditional cytotoxic treatments with immunotherapeutic agents. The most extensively used models employed for the exploration of NSCLC biology and therapy have been 2D cell lines and murine models. However, studying cancer immunology requires appropriately complex models. 3D platforms, including organoid models, are quickly advancing powerful tools to study immune cell-epithelial cell interactions within the tumor microenvironment. Co-cultures of immune cells along with NSCLC organoids allow for an in vitro observation of the tumor microenvironment dynamics closely resembling in vivo settings. Ultimately, the implementation of 3D organoid technology into tumor microenvironment-modeling platforms might facilitate the exploration of macrophage-targeted therapies in NSCLC immunotherapeutic research, thus establishing a new frontier in NSCLC treatment.

Identifying key transcription factors and immune infiltration in non-small-cell lung cancer using weighted correlation network and Cox regression analyses

Introduction

Lung cancer is one of the most common cancers and a significant cause of cancer-related deaths. Non-small cell lung cancer (NSCLC) accounts for about 85% of all lung cancer cases. Therefore, it is crucial to identify effective diagnostic and therapeutic methods. In addition, transcription factors are essential for eukaryotic cells to regulate their gene expression, and aberrant expression transcription factors are an important step in the process of oncogenesis in NSCLC.

Methods

Differentially expressed transcription factors between NSCLC and normal tissues by analyzing mRNA profiling from The Cancer Genome Atlas (TCGA) database program were identified. Weighted correlation network analysis (WGCNA) and line plot of least absolute shrinkage and selection operator (LASSO) were performed to find prognosis-related transcription factors. The cellular functions of transcription factors were performed by 5-ethynyl-2'-deoxyuridine (EdU) assay, wound healing assay, cell invasion assay in lung cancer cells.

Results

We identified 725 differentially expressed transcription factors between NSCLC and normal tissues. Three highly related modules for survival were discovered, and transcription factors highly associated with survival were obtained by using WGCNA. Then line plot of LASSO was applied to screen transcription factors related to prognosis and build a prognostic model. Consequently, SETDB2, SNAI3, SCML4, and ZNF540 were identified as prognosis-related transcription factors and validated in multiple databases. The low expression of these hub genes in NSCLC was associated with poor prognosis. The deletions of both SETDB2 and SNAI3 were found to promote proliferation, invasion, and stemness in lung cancer cells. Furthermore, there were significant differences in the proportions of 22 immune cells between the high- and low-score groups.

Discussion

Therefore, our study identified the transcription factors involved in regulating NSCLC, and we constructed a panel for the prediction of prognosis and immune infiltration to inform the clinical application of transcription factor analysis in the prevention and treatment of NSCLC.

3D cancer models: One step closer to in vitro human studies

Cancer immunotherapy is the great breakthrough in cancer treatment as it displayed prolonged progression-free survival over conventional therapies, yet, to date, in only a minority of patients. In order to broad cancer immunotherapy clinical applicability some roadblocks need to be overcome, first among all the lack of preclinical models that faithfully depict the local tumor microenvironment (TME), which is known to dramatically affect disease onset, progression and response to therapy. In this review, we provide the reader with a detailed overview of current 3D models developed to mimick the complexity and the dynamics of the TME, with a focus on understanding why the TME is a major target in anticancer therapy. We highlight the advantages and translational potentials of tumor spheroids, organoids and immune Tumor-on-a-Chip models in disease modeling and therapeutic response, while outlining pending challenges and limitations. Thinking forward, we focus on the possibility to integrate the know-hows of micro-engineers, cancer immunologists, pharmaceutical researchers and bioinformaticians to meet the needs of cancer researchers and clinicians interested in using these platforms with high fidelity for patient-tailored disease modeling and drug discovery.

Disabled-2 (DAB2): A Key Regulator of Anti- and Pro-Tumorigenic Pathways

Disabled-2 (DAB2), a key adaptor protein in clathrin mediated endocytosis, is implicated in the regulation of key signalling pathways involved in homeostasis, cell positioning and epithelial to mesenchymal transition (EMT). It was initially identified as a tumour suppressor implicated in the initiation of ovarian cancer, but was subsequently linked to many other cancer types. DAB2 contains key functional domains which allow it to negatively regulate key signalling pathways including the mitogen activated protein kinase (MAPK), wingless/integrated (Wnt) and transforming growth factor beta (TGFβ) pathways. Loss of DAB2 is primarily associated with activation of these pathways and tumour progression, however this review also explores studies which demonstrate the complex nature of DAB2 function with pro-tumorigenic effects. A recent strong interest in microRNAs (miRNA) in cancer has identified DAB2 as a common target. This has reignited an interest in DAB2 research in cancer. Transcriptomics of tumour associated macrophages (TAMs) has also identified a pro-metastatic role of DAB2 in the tumour microenvironment. This review will cover the broad depth literature on the tumour suppressor role of DAB2, highlighting its complex relationships with different pathways. Furthermore, it will explore recent findings which suggest DAB2 has a more complex role in cancer than initially thought.

[Exosomal miR-10b Promotes Invasion and Epithelial-mesenchymal Transformation of Lung Adenocarcinoma A549 Cells by Regulating Macrophage M2 Polarization]

BACKGROUND

Metastasis is the main cause of death in patients with lung cancer. Macrophages are innate immune cells that play important roles in cancer metastasis. Exosomes could play an important role of communication between tumor cells and macrophages. This study investigated the effect of miR-10b on cell growth invasion and epithelial mesenchymal transition (EMT) in lung adenocarcinoma A549 cell exosomes.

METHODS

Exosomes were isolated from A549 cells and identified by transmission electron microscopy (TEM) and Western blot. CCK-8 assay and flow cytometry were used to detect cell proliferation and apoptosis. Cell migration and invasion were detected by Transwell assay. The expression of mRNA and protein were assessed by quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blot, respectively.

RESULTS

The expression of miR-10b was up-regulated in non-small cell lung cancer, and miR-10b inhibitor could inhibit the proliferation of A549 cell. Meanwhile, the tumor cell-derived exosome miR-10b promoted the invasion of A549 cell and EMT by promoting the M2 polarization of macrophages.

CONCLUSIONS

Tumor cell-derived exosome miR-10b promotes A549 cell invasion and EMT through M2 macrophage polarization.

Integration of single-cell and bulk RNA-seq to establish a predictive signature based on the differentiation trajectory of M2 macrophages in lung adenocarcinoma

Background: Tumor-associated macrophages as important members of the tumor microenvironment, are highly plastic and heterogeneous. TAMs can be classified into two preliminary subtypes: M1 and M2 macrophages. M2 macrophages are significantly associated with the progression of lung adenocarcinoma. However, no study has investigated the heterogeneity among M2 macrophages and their differentiation-related genes at the single-cell level to guide the clinical treatment of lung adenocarcinoma.

Methods: Using the available annotation information from the Tumor Immune Single-cell Hub database, we clustered and annotated 12 lung adenocarcinoma samples using the R package ‘Seurat’. Subsequently, we extracted M2 macrophages for secondary clustering analysis and performed cell trajectory analysis using the R package ‘monocle2’. Based on heterogeneous genes associated with the differentiation trajectory of M2 macrophages, we established a prognostic lung adenocarcinoma model using Lasso-Cox and multivariate stepwise regression. In addition, we also performed immunotherapy and chemotherapy predictions.

Results: M2 macrophages exhibit heterogeneity among themselves. M2 macrophages in different differentiation states showed significant differences in pathway activation and immune cell communication. Prognostic signature based on heterogeneous genes can be used to classify the prognostic status and abundance of immune cell infiltration in lung adenocarcinoma patients. In addition, the calculation of the Tumor Immune Dysfunction and Exclusion (TIDE) algorithm and the validation of the GSE126044 database indicated that lung adenocarcinoma patients with high-risk scores had poorer treatment outcomes when receiving immune checkpoint inhibitors treatment.

Conclusion: Based on scRNA-seq and Bulk-seq data, we identified M2 macrophage-associated prognostic signature with a potential clinical utility to improve precision therapy.

Tumor microenvironment in lung cancer-derived brain metastasis

ABSTRACT

Brain metastasis (BM) is the leading cause of mortality in lung cancer patients. The process of BM (from initial primary tumor development, migration and intravasation, dissemination and survival in the bloodstream, extravasation, to colonization and growth to metastases) is a complex process for which few tumor cells complete the entire process. Recent research on BM of lung cancer has recently stressed the essential role of tumor microenvironment (TME) in assisting tumor cells in the completion of each BM step. This review summarizes recent studies regarding the effects of TME on tumor cells in the entire process of BM derived from lung cancer. The identification of vulnerable targets in the TME and their prospects to provide novel therapeutic opportunities are also discussed.

A multi-organ-on-chip to recapitulate the infiltration and the cytotoxic activity of circulating NK cells in 3D matrix-based tumor model

The success of immunotherapeutic approaches strictly depends on the immune cells interaction with cancer cells. While conventional in vitro cell cultures under-represent the complexity and dynamic crosstalk of the tumor microenvironment, animal models do not allow deciphering the anti-tumor activity of the human immune system. Therefore, the development of reliable and predictive preclinical models has become crucial for the screening of immune-therapeutic approaches. We here present an organ-on-chip organ on chips (OOC)-based approach for recapitulating the immune cell Natural Killer (NK) migration under physiological fluid flow, infiltration within a 3D tumor matrix, and activation against neuroblastoma cancer cells in a humanized, fluid-dynamic environment. Circulating NK cells actively initiate a spontaneous “extravasation” process toward the physically separated tumor niche, retaining their ability to interact with matrix-embedded tumor cells, and to display a cytotoxic effect (tumor cell apoptosis). Since NK cells infiltration and phenotype is correlated with prognosis and response to immunotherapy, their phenotype is also investigated: most importantly, a clear decrease in CD16-positive NK cells within the migrated and infiltrated population is observed. The proposed immune-tumor OOC-based model represents a promising approach for faithfully recapitulating the human pathology and efficiently employing the immunotherapies testing, eventually in a personalized perspective. An immune-organ on chip to recapitulate the tumor-mediated infiltration of circulating immune cells within 3D tumor model.

G-CSF/GM-CSF-induced hematopoietic dysregulation in the progression of solid tumors

There are two types of abnormal hematopoiesis in solid tumor occurrence and treatment: pathological hematopoiesis, and myelosuppression induced by radiotherapy and chemotherapy. In this review, we primarily focus on the abnormal pathological hematopoietic differentiation in cancer induced by tumor-released granulocyte colony stimulating factor (G-CSF) and granulocyte-macrophage colony stimulating factor (GM-CSF). As key factors in hematopoietic development, G-CSF/GM-CSF are well-known facilitators of myelopoiesis and mobilization of hematopoietic stem cells (HSCs). In addition, these two cytokines can also promote or inhibit tumors, dependent on tumor type. In multiple cancer types, hematopoiesis is greatly enhanced and abnormal lineage differentiation is induced by these two cytokines. Here, dysregulated hematopoiesis induced by G-CSF/GM-CSF in solid tumors and its mechanism are summarized, and the prognostic value of G-CSF/GM-CSF-associated dysregulated hematopoiesis for tumor metastasis is also briefly highlighted.

Oxy210, a Semi-Synthetic Oxysterol, Exerts Anti-Inflammatory Effects in Macrophages via Inhibition of Toll-like Receptor (TLR) 4 and TLR2 Signaling and Modulation of Macrophage Polarization

Inflammatory responses by the innate and adaptive immune systems protect against infections and are essential to health and survival. Many diseases including atherosclerosis, osteoarthritis, rheumatoid arthritis, psoriasis, and obesity involve persistent chronic inflammation. Currently available anti-inflammatory agents, including non-steroidal anti-inflammatory drugs, steroids, and biologics, are often unsafe for chronic use due to adverse effects. The development of effective non-toxic anti-inflammatory agents for chronic use remains an important research arena. We previously reported that oral administration of Oxy210, a semi-synthetic oxysterol, ameliorates non-alcoholic steatohepatitis (NASH) induced by a high-fat diet in APOE*3-Leiden.CETP humanized mouse model of NASH and inhibits expression of hepatic and circulating levels of inflammatory cytokines. Here, we show that Oxy210 also inhibits diet-induced white adipose tissue inflammation in APOE*3-Leiden.CETP mice, evidenced by the inhibition of adipose tissue expression of IL-6, MCP-1, and CD68 macrophage marker. Oxy210 and related analogs exhibit anti-inflammatory effects in macrophages treated with lipopolysaccharide in vitro, mediated through inhibition of toll-like receptor 4 (TLR4), TLR2, and AP-1 signaling, independent of cyclooxygenase enzymes or steroid receptors. The anti-inflammatory effects of Oxy210 are correlated with the inhibition of macrophage polarization. We propose that Oxy210 and its structural analogs may be attractive candidates for future therapeutic development for targeting inflammatory diseases.

13-Methyl-palmatrubine shows an anti-tumor role in non-small cell lung cancer via shifting M2 to M1 polarization of tumor macrophages

BACKGROUND

Previous studies have substantiated that M2-activated tumor-associated macrophages (M2-TAMs) are involved in multiple malignancies. Presently, we probe the impact and related mechanisms of 13-methyl-palmatrubine (13MP), the Corydalis yanhusuo extract, on M2-TAM-mediated non-small cell lung cancer (NSCLC) development.

METHODS

IL-4 and IL-13 were adopted to induce M2-TAMs. The polarization state of TAMs was evaluated by quantitative reverse transcription PCR (qRT-PCR), Western blot (WB) and cellular immunofluorescence. NSCLC cells (A549 and NCL-H1975) were co-cultured with the conditioned medium (CM) of M2-TAMs. Followed by 13MP treatment, cell viability, proliferation, invasion, epithelial-mesenchymal transition (EMT), and in-vivo growth of NSCLC cells were determined. Additionally, human umbilical vein endothelial cells (HUVECs) were co-cultured with the CM of M2-TAMs. The tube formation assay was made to test the tube formation capacity of HUVECs, and the expression of MMP3, MMP9, and VEGF was assessed by WB in the co-culture model. Mechanistically, WB was performed to validate the expression of the PI3K/AKT and JAK/STAT3 pathways in NSCLC cells (A549 and NCL-H1975) as well as in endothelial cell lines co-cultured with M2-TAMs.

RESULTS

13MP inhibited the proliferation, invasion, EMT, growth and enhanced apoptosis of NSCLC cells. 13MP dose-dependently boosted the polarization of TAM from M2 to M1 state. M2-TAMs enhanced the malignant behaviors of NSCLC cells, whereas 13MP hindered M2-TAM-mediated NSCLC cell proliferation and invasion. Meanwhile, 13MP weakened the M2-TAM-mediated angiogenesis. Moreover, 13MP inactivated the PI3K/AKT and JAK/STAT3 signaling in A549 cells, NCL-H1975 cells and HUVECs.

CONCLUSION

13MP suppresses TAM-mediated NSCLC progression via transforming the polarization of TAM from M2 to M1.

Atractylenolide II inhibits tumor-associated macrophages (TAMs)-induced lung cancer cell metastasis

OBJECTIVE

M2-like tumor-associated macrophages (TAMs) play a crucial role in promoting tumor proliferation, angiogenesis, and metastasis. In the current study, we investigated the relationship between macrophage polarization and the antitumor effect of Atractylenolide II (AT-II) in lung cancer cells.

MATERIALS AND METHODS

Cell viability, migration, and invasion were determined by MTT assay, wound healing assay, and transwell assay, respectively. Flow cytometry analysis showed the percentage of CD206⁺ cells. Gene expression was determined by real-time PCR, western blotting, and immunofluorescence staining. Lewis lung carcinoma mouse xenograft and metastasis models were used to examine the effects of AT-II on lung cancer in vivo.

RESULTS

AT-II (2.5 and 5 µM) did not cause significant inhibition of A549 cell viability but markedly inhibited IL-4/IL-13-induced M2-like polarization, evidenced by the decreased expression of the M2 surface marker CD206, down-regulation of specific M2-marker genes (Arg-1, IL-10 and TGF-β) as well as inhibition of M2 macrophages-mediated invasion and migration of A549 cells. In addition, AT-II inhibited IL-4/IL-13-induced activation of the STAT6 signaling pathway that is vital in the M2-like polarization of macrophages. In animal models, administration of AT-II (50 mg kg^-1, i.g., QD for 21 days) significantly inhibited tumor growth, reduced pulmonary metastatic nodules, and down-regulated the percentages of M2 macrophages (F4/80⁺ and CD206⁺) in total macrophages (F4/80⁺) in tumor tissues and pulmonary metastatic nodules.

CONCLUSIONS

AT-II effectively inhibits M2-like polarization, thereby inhibiting lung cancer cell metastasis both in vivo and in vitro, revealing a novel potential strategy for the antitumor effect of AT-II.

The centromere-associated protein CENPU promotes cell proliferation, migration, and invasiveness in lung adenocarcinoma

CENPU, encoding an important factor involved in kinetochore assembly during mitosis, is associated with shorter survival rates in lung adenocarcinoma (LUAD) patients. CENPU promotes growth rates and invasive behavior of LUAD cells; however, its mechanism of action in LUAD progression remains to be elucidated. CENPU mRNA and protein expression were elevated in LUAD tumors, and high CENPU gene expression was associated with inferior survival prognosis in LUAD patients. CENPU knockdown inhibited LUAD cell proliferation, clone formation, migration, invasion, and epithelial-mesenchymal transition (EMT) in addition to inducing cell cycle arrest and apoptosis in vitro and reduced LUAD xenograft tumor growth in vivo. Furthermore, we identified CENPU-regulated genes significantly enriched for proliferation and apoptosis pathways, and identified HSP Family Member C10 (DNAJC10) as putative effector of CENPU. CENPU knockdown produced DNAJC10 protein downregulation, and DNAJC10 overexpression partially rescued the phenotypic effects of CENPU knockdown in LUAD cells. Moreover, CENPU's coiled-coil domain was essential for CENPU's phenotypic effects in LUAD cells. In conclusion, the kinetochore component CENPU plays a critical role in LUAD cell proliferation and invasiveness. Targeting CENPU-DNAJC10 axis may inhibit LUAD tumor cell proliferation and metastasis.

Omega-3 fatty acids decrease CRYAB, production of oncogenic prostaglandin E2 and suppress tumor growth in medulloblastoma

AIMS

Medulloblastoma (MB) is one of the most common malignant central nervous system tumors of childhood. Despite intensive treatments that often leads to severe neurological sequelae, the risk for resistant relapses remains significant. In this study we have evaluated the effects of the ω3-long chain polyunsaturated fatty acids (ω3-LCPUFA) docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) on MB cell lines and in a MB xenograft model.

MAIN METHODS

Effects of ω3-LCPUFA treatment of MB cells were assessed using the following: WST-1 assay, cell death probes, clonogenic assay, ELISA and western blot. MB cells were implanted into nude mice and the mice were randomized to DHA, or a combination of DHA and EPA treatment, or to control group. Treatment effects in tumor tissues were evaluated with: LC-MS/MS, RNA-sequencing and immunohistochemistry, and tumors, erythrocytes and brain tissues were analyzed with gas chromatography.

KEY FINDINGS

ω3-LCPUFA decreased prostaglandin E2 (PGE₂) secretion from MB cells, and impaired MB cell viability and colony forming ability and increased apoptosis in a dose-dependent manner. DHA reduced tumor growth in vivo, and both PGE₂ and prostacyclin were significantly decreased in tumor tissue from treated mice compared to control animals. All ω3-LCPUFA and dihomo-γ-linolenic acid increased in tumors from treated mice. RNA-sequencing revealed 10 downregulated genes in common among ω3-LCPUFA treated tumors. CRYAB was the most significantly altered gene and the downregulation was confirmed by immunohistochemistry.

SIGNIFICANCE

Our findings suggest that addition of DHA and EPA to the standard MB treatment regimen might be a novel approach to target inflammation in the tumor microenvironment.

Epigenome-wide three-way interaction study identifies a complex pattern between TRIM27, KIAA0226, and smoking associated with overall survival of early-stage NSCLC

The interaction between DNA methylation of tripartite motif containing 27 (cg05293407_TRIM27 ) and smoking has previously been identified to reveal histologically heterogeneous effects of TRIM27 DNA methylation on early-stage non-small-cell lung cancer (NSCLC) survival. However, to understand the complex mechanisms underlying NSCLC progression, we searched three-way interactions. A two-phase study was adopted to identify three-way interactions in the form of pack-year of smoking (number of cigarettes smoked per day × number of years smoked) × cg05293407_TRIM27  × epigenome-wide DNA methylation CpG probe. Two CpG probes were identified with FDR-q ≤ 0.05 in the discovery phase and P ≤ 0.05 in the validation phase: cg00060500_KIAA0226 and cg17479956_EXT2 . Compared to a prediction model with only clinical information, the model added 42 significant three-way interactions using a looser criterion (discovery: FDR-q ≤ 0.10, validation: P ≤ 0.05) had substantially improved the area under the receiver operating characteristic curve (AUC) of the prognostic prediction model for both 3-year and 5-year survival. Our research identified the complex interaction effects among multiple environment and epigenetic factors, and provided therapeutic target for NSCLC patients.

Cancer-on-a-Chip: Models for Studying Metastasis

Simple Summary

Microfluidic-based cancer-on-a-chip models are powerful tools to study the tumor microenvironment (TME). Two-dimensional cell culture cannot recapitulate TME. In vivo animal models can better represent the TME, but their physiology is vastly different from that of humans. Although three-dimensional tumor models can bridge the gap between in vitro and in vivo examination, they are still unable to test many crucial cues from the TME, such as mechanical cues, cell–cell, and cell–extracellular interactions. Cancer-on-a-chip platforms enable studying the metastatic process in a step-wise manner with precise control. We present an overview of the recent advances in cancer-on-a-chip models on metastasis including models that mimic mechanical cues. This review article will provide knowledge of the latest progress made on cancer-on-a-chip models.

Abstract

The microfluidic-based cancer-on-a-chip models work as a powerful tool to study the tumor microenvironment and its role in metastasis. The models recapitulate and systematically simplify the in vitro tumor microenvironment. This enables the study of a metastatic process in unprecedented detail. This review examines the development of cancer-on-a-chip microfluidic platforms at the invasion/intravasation, extravasation, and angiogenesis steps over the last three years. The on-chip modeling of mechanical cues involved in the metastasis cascade are also discussed. Finally, the popular design of microfluidic chip models for each step are discussed along with the challenges and perspectives of cancer-on-a-chip models.

CRYAB predicts clinical prognosis and is associated with immunocyte infiltration in colorectal cancer

Background

αB-Crystallin (CRYAB) is differentially expressed in various tumors. However, the correlation between CRYAB and immune cell infiltration in colorectal cancer (CRC) remains unclear.

Materials & Methods

Kaplan-Meier survival curves in The Cancer Genome Atlas (TCGA) were used to evaluate the relationship between CRYAB expression and both overall survival and progression-free survival. The relationships between CRYAB expression and infiltrating immune cells and their corresponding gene marker sets were examined using the TIMER database.

Results

The expression of CRYAB was lower in CRC tumor tissues than in normal tissues (P < 0.05). High CRYAB gene expression and high levels of CRYAB gene methylation were correlated with high-grade malignant tumors and more advanced tumor, nodes and metastasis (TNM) cancer stages. In addition, in colorectal cancer, there was a positive correlation between CRYAB expression and immune infiltrating cells including neutrophils, macrophages, CD8 + T cells, and CD4 + T cells, as well as immune-related genes including CD2, CD3D, and CD3E. Methylation sites such as cg13084335, cg15545878, cg13210534, and cg15318568 were positively correlated with low expression of CRYAB.

Conclusion

Because CRYAB likely plays an important role in immune cell infiltration, it may be a potential tumor-suppressor gene in CRC and a potential novel therapeutic target and predictive biomarker for colorectal cancer (CRC).

Roles of tumor-associated macrophages in tumor progression: implications on therapeutic strategies

Macrophages are heterogeneous cells that present as different functional phenotypes due to their plasticity. They can be classified into two categories, namely M1- and M2-like macrophages, which are involved in processes as diverse as anti-tumor activity and immunosuppressive tumor promotion. Tumor-associated macrophages (TAMs) are defined as being of an M2-type and are considered as the active component in tumor microenvironment. TAMs are involved in multiple processes of tumor progression through the expression of cytokines, chemokines, growth factors, protein hydrolases and more, which lead to enhance tumor cell proliferation, angiogenesis, and immunosuppression, which in turn supports invasion and metastasis. It is assumed that the abundance of TAMs in major solid tumors is correlated to a negative patient prognosis. Because of the currently available data of the TAMs’ role in tumor development, these cells have emerged as a promising target for novel cancer treatment strategies. In this paper, we will briefly describe the origins and types of TAMs and will try to comprehensively show how TAMs contribute to tumorigenesis and disease progression. Finally, we will present the main TAM-based therapeutic strategies currently available.

Tumor-associated macrophages in lung carcinoma: From mechanism to therapy

Tumor-associated macrophages (TAMs), which could be classified into the classical (M1-like) and alternatively activated (M2-like) phenotype, were considered to be important tumor-promoting components in lung cancer microenvironment. Several studies reported that TAMs in lung tumor islet or stroma are usually correlated with poor prognosis. Further studies showed that TAMs could promote the initiation of tumor cells, inhibit antitumor immune responses, and stimulate tumor angiogenesis and subsequently tumor metastasis of lung carcinoma. Currently, TAMs have been considered as penitential targets of lung cancer. This review summarizes from the fundamental information of TAMs to the its role in metastasis and present evidence for TAMs as a potential target of cancer therapy.

Molecular insights of metastasis and cancer progression derived using 3D cancer spheroid co-culture in vitro platform

The multistep metastasis process is carried out by the combinatorial effect of the stromal cells and the cancerous cells and plays vital role in the cancer progression. The scaffold/physical cues aided 3D cancer spheroid imitates the spatiotemporal organization and physiological properties of the tumor. Understanding the role of the key players in different stages of metastasis, the molecular cross-talk between the stromal cells and the cancer cells contributing in the advancement of the metastasis through 3D cancer spheroid co-culture in vitro platform is the center of discussion in the present review. This state-of-art in vitro platform utilized to study the cancer cell host defence and the role of exosomes in the cross talk leading to cancer progression has been critically examined here. 3D cancer spheroid co-culture technique is the promising next-generation in vitro approach for exploring potent treatments and personalized medicines to combat cancer metastasis leading to cancer progression.

Benzo[a]pyrene immunogenetics and immune archetype reprogramming of lung

Overexposure to carcinogenic precursor, benzo[a]pyrene [BaP], modulates the lung immune microenvironment. The present review seeks to elucidate novel pathways behind the tumor effect of BaP in the lungs, emphasizing immunomodulatory mediators and immune cells. In this review, BaP reprograms lung immune microenvironment through modulating transforming growth factor-beta (TGF-β), programmed cell death 1 (PD-1), cytotoxic T lymphocyte antigen-4 (CTLA-4), Interleukin 12 (IL-12), indoleamine 2,3 dioxygenase (IDO), forkhead box protein P3 (FOXP3) and interferon-gamma (IFN-γ) levels. Moreover, BaP modulated lung immune cellular architecture such as dendritic cells, T cells, Tregs, macrophages, neutrophils, and myeloid-derived suppressor cells (MDSCs). All mentioned changes in immune architecture and mediators lead to the induction of lung cancer.