Roles of CCL2-CCR2 Axis in the Tumor Microenvironment

Patient-specific vascularized tumor model: Blocking monocyte recruitment with multispecific antibodies targeting CCR2 and CSF-1R

Tumor-associated inflammation drives cancer progression and therapy resistance, often linked to the infiltration of monocyte-derived tumor-associated macrophages (TAMs), which are associated with poor prognosis in various cancers. To advance immunotherapies, testing on immunocompetent pre-clinical models of human tissue is crucial. We have developed an in vitro model of microvascular networks with tumor spheroids or patient tissues to assess monocyte trafficking into tumors and evaluate immunotherapies targeting the human tumor microenvironment. Our findings demonstrate that macrophages in vascularized breast and lung tumor models can enhance monocyte recruitment via CCL7 and CCL2, mediated by CSF-1R. Additionally, a multispecific antibody targeting CSF-1R, CCR2, and neutralizing TGF-β (CSF1R/CCR2/TGF-β Ab) repolarizes TAMs towards an anti-tumoral M1-like phenotype, reduces monocyte chemoattractant protein secretion, and blocks monocyte migration. This antibody also inhibits monocyte recruitment in patient-specific vascularized tumor models. In summary, this vascularized tumor model recapitulates the monocyte recruitment cascade, enabling functional testing of innovative therapeutic antibodies targeting TAMs in the tumor microenvironment.

Bindarit Attenuates Neuroinflammation After Subarachnoid Hemorrhage by Regulating the CCL2/CCR2/NF-κB Pathway

BACKGROUND AND PURPOSE

The poor prognosis of subarachnoid hemorrhage (SAH) is closely linked to neuroinflammation and neuronal apoptosis. The CCL2/CCR2 signaling axis, a cytoplasmic pathway responsible for recruiting immune cells, plays a significant role in regulating neuroinflammation in neurological diseases. Bindarit, an inhibitor of chemokine CC motif ligand 2(CCL2), has been shown to demonstrate neuroprotective effects in various central nervous system diseases. This study aimed to investigate the anti-inflammatory effects of Bindarit after SAH.

METHODS

Pre-processed RNA-seq transcriptome datasets GSE79416 from the Gene Expression Omnibus (GEO) database were analyzed to identify genes differentially expressed between mice with SAH and control mice using bioinformatics methods. Bindarit, a CCL2 inhibitor, was administered intraperitoneally one hour after SAH. Recombinant CCL2 protein was administered via the lateral ventricle one hour before SAH induction. HT22 cells were cultured and stimulated by oxyhemoglobin to establish an in vitro model of SAH.

RESULTS

Analysis of GSE79416 datasets revealed upregulation of CCL2 expression, identifying it as a hub gene in SAH. Following SAH, CCL2 expression increased in rat brain tissue, reaching the highest level 24hours after SAH. Bindarit improved the short-term and long-term neurological deficits after SAH and also exhibited the anti-inflammatory effects following SAH. Conversely, administration of recombinant CCL2 protein attenuated the protective effects of Bindarit. In vitro, Bindarit significantly reduced neuronal inflammation.

CONCLUSION

Endogenous CCL2 expression was upregulated in the rat SAH model. Bindarit improved neurological functions and reduced neuroinflammation by regulating the CCL2/CCR2/NF-κB pathway in early brain injury after SAH.

Decoding the complex web: Cellular and molecular interactions in the lung tumor microenvironment

The lung tumor microenvironment (TME) or stroma is a dynamic space of numerous cells and their released molecules. This complicated web regulates tumor progression and resistance to different modalities. Lung cancer cells in conjunction with their stroma liberate a wide range of factors that dampen antitumor attacks by innate immunity cells like natural killer (NK) cells and also adaptive responses by effector T cells. These factors include numerous growth factors, exosomes and epigenetic regulators, and also anti-inflammatory cytokines. Understanding the intricate interactions between tumor cells and various elements within the lung TME, such as immune and stromal cells can help provide novel strategies for better management and treatment of lung malignancies. The current article discusses the complex network of cells and signaling molecules, which mediate communications in lung TME. By elucidating these multifaceted interactions, we aim to provide insights into potential therapeutic targets and strategies for lung cancer treatment.

Increased CCL2/CCR2 axis promotes tumor progression by increasing M2 macrophages in MYC/BCL2 double-expressor DLBCL

ABSTRACT

The pathogenesis of myelocytomatosis oncogene (MYC) and B-cell lymphoma 2 (BCL2) double-expressor diffuse large B-cell lymphoma (DE-DLBCL) remains unclear. To investigate how MYC and BCL2 contribute to tumor aggressiveness, we analyzed tumors from 14 patients each with DE-DLBCL and non-DE-DLBCL using whole transcriptome sequencing. Validation was performed using publicly available data sets, tumor tissues from 126 patients, DLBCL cell lines, and a syngeneic mouse lymphoma model. Our transcriptome analysis revealed significantly elevated messenger RNA levels of C-C motif chemokine ligand 2 (CCL2) and C-C chemokine receptor type 2 (CCR2) in DE-DLBCLs when compared with non-DE-DLBCLs (adjusted P value < .05). Transcriptomic analysis of public data sets and immunohistochemistry corroborated these findings, indicating increased levels of M2 macrophages but a reduction in T-cell infiltration in DE-DLBCLs when compared with non-DE-DLBCLs (all P < .05). CCR2 expression was observed mainly in tumor-infiltrating macrophages and not in DLBCL cells. Increased expression of CCL2 and CCR2 was significantly associated with a poor prognosis in patients with DLBCL. In the in vitro analyses, MYChigh/BCL2high DLBCL cells showed higher CCL2 expression and secretion than MYClow/BCL2low cells. MYC and BCL2 increased CCL2 expression and secretion by upregulation of nuclear factor κB p65 in DLBCL cells, and CCL2 promoted M2 polarization of macrophages. In a mouse lymphoma model, CCL2 contributed to the immunosuppressive microenvironment and tumor growth of MYChigh/BCL2high tumors. We demonstrated that the increased CCL2/CCR2 axis confers aggressiveness to DE-DLBCL by increasing M2 polarization and can be a potential therapeutic target.

Increased QPCT gene expression by the hepatitis B virus promotes HBV replication

Glutamine cyclase, an enzyme involved in posttranslational modifications, is encoded by the glutaminyl-peptide cyclotransferase (QPCT) gene. Gene microarray analysis revealed that the QPCT gene was highly expressed in HepG2.2.15 cells compared with that in HepG2 cells. The serum expression level of the QPCT gene was detected by ELISA and was significantly greater in HBV-infected patients than in healthy controls. The mRNA and protein expression levels of the QPCT gene were markedly greater in the HBV-expressing cell lines (HepG2.2.15, and HepG2 and Huh7 cells transfected with the pBlu-HBV plasmid) than in the HepG2 and Huh7 cells. The levels of HBV pgRNA and HBV-DNA copy number, as well as the levels of HBeAg and HBsAg, also increased in the HepG2 and Huh7 cell lines cotransfected with the QPCT gene expression plasmid and the HBV 1.3-fold plasmid. Our study indicated that HBV can promote the expression of the QPCT gene, which in turn promotes the expression and replication of HBV.

Identification of SPP1+ macrophages in promoting cancer stemness via vitronectin and CCL15 signals crosstalk in liver cancer

Macrophages play a multifaceted role in cancer biology, with both pro-tumorigenic and anti-tumorigenic functions. Understanding the mechanisms underlying macrophage involvement in cancer progression is essential for the development of therapeutic strategies. Our study analyzed single-cell RNA sequencing data from 12 patients with liver cancer and identified a subpopulation of macrophages characterized by elevated expression of SPP1, which correlates with poor prognosis in liver cancer patients. These SPP1+ macrophages induce upregulation of tumor stemness through a vitronectin (VTN)-dependent paracrine mechanism. Mechanistically, VTN derived from SPP1+ macrophages promote integrin αvβ5/adenosine 5'-monophosphate-activated protein kinase (AMPK)/Yes-associated protein 1 (YAP1)/SYR-box transcription factor 4 (SOX4) signaling, mediating liver tumor stemness and progression. Conversely, CCL15 produced by liver cancer cells drives polarization of M0 macrophages toward an SPP1+ macrophage phenotype, establishing a positive feedback loop of macrophage-tumor stemness. Furthermore, the presence of SPP1+ macrophages confers chemoresistance in liver cancer, and inhibition of the macrophage-tumor feedback loop through targeting integrin αvβ5/YAP1 signaling sensitizes liver cancer cells to chemotherapy. Our study highlights the crucial role of SPP1+ macrophages in liver cancer progression, providing novel insights for clinical liver cancer therapy.

Interactions and communications in the prostate tumour microenvironment: evolving towards effective cancer therapy

Prostate cancer is one of the most common malignancies in men. The tumour microenvironment (TME) has a critical role in the initiation, progression, and metastasis of prostate cancer. TME contains various cell types, including cancer-associated fibroblasts (CAFs), endothelial cells, immune cells such as macrophages, lymphocytes B and T, natural killer (NK) cells, and other proteins such as extracellular matrix (ECM) components. The interactions and communications between these cells within the TME are crucial for the growth and response of various solid tumours, such as prostate cancer to different anticancer modalities. In this review article, we exemplify the various mechanisms by which the TME influences prostate cancer progression. The roles of different cells, cytokines, chemokines, and growth factors in modulating the immune response and prostate tumour growth will be discussed. The impact of these cells and factors and other ECM components on tumour cell invasion and metastasis will also be discussed. We explain how these interactions in TME can affect the response of prostate cancer to therapy. We also highlight the importance of understanding these interactions to develop novel therapeutic approaches for prostate cancer.

Intratumoral CXCL12 Gradients Contextualize Tumor Cell Invasion, Migration and Immune Suppression in Breast Cancer

Although the CXCL12/CXCR4 pathway has been prior investigated for its prometastatic and immuno- suppressive roles in the tumor microenvironment, evidence on the spatiotemporal regulation of these hallmarks has been lacking. Here, we demonstrate that CXCL12 forms a gradient specifically around cancer cell intravasation doorways, also known as Tumor Microenvironment of Metastasis (TMEM) doorways, thus facilitating the chemotactic translocation of prometastatic tumor cells expressing CXCR4 toward the perivascular TMEM doorways for subsequent entry into peripheral circulation. Fur- thermore, we demonstrate that the CXCL12-rich micro-environment around TMEM doorways may cre- ate immunosuppressive niches, whereby CD8 + T cells, despite being attracted to these regions, often exhibit reduced effector functions, limiting their efficacy. While the CXCL12/CXCR4 pathway can mini- mally influence the overall composition of immune cell populations, it biases the distribution of CD8 + T cells away from TMEM doorways, justifying its prior-established role as immunosuppressive factor for CD8 + T cells. Our research suggests that the complex interactions between CXCL12 and the various tumor and immune cell types contributes not only to the completion of the initial steps of the metastatic cascade, but also offers an immunological "sanctuary" to prometastatic tumor cells homed around TMEM doorways. Overall, our study enhances our current understanding on the mechanisms, via which CXCL12 orchestrates tumor cell behavior and immune dynamics, potentially guiding future thera- peutic strategies to combat breast cancer metastasis and improve anti-tumor immunity.

Development of a Competitive Nutrient-Based T-Cell Immunotherapy Designed to Block the Adaptive Warburg Effect in Acute Myeloid Leukemia

Background: T-cell-based adoptive cell therapies have emerged at the forefront of cancer immunotherapies; however, failed long-term survival and inevitable exhaustion of transplanted T lymphocytes in vivo limits clinical efficacy. Leukemia blasts possess enhanced glycolysis (Warburg effect), exploiting their microenvironment to deprive nutrients (e.g., glucose) from T cells, leading to T-cell dysfunction and leukemia progression. Methods: Thus, we explored whether genetic reprogramming of T-cell metabolism could improve their survival and empower T cells with a competitive glucose-uptake advantage against blasts and inhibit their uncontrolled proliferation. Results: Here, we discovered that high-glucose concentration reduced the T-cell expression of glucose transporter GLUT1 (SLC2A1) and TFAM (mitochondrion transcription factor A), an essential transcriptional regulator of mitochondrial biogenesis, leading to their impaired expansion ex vivo. To overcome the glucose-induced genetic deficiency in metabolism, we engineered T cells with lentiviral overexpression of SLC2A1 and/or TFAM transgene. Multi-omics analyses revealed that metabolic reprogramming promoted T-cell proliferation by increasing IL-2 release and reducing exhaustion. Moreover, the engineered T cells competitively deprived glucose from allogenic blasts and lessened leukemia burden in vitro. Conclusions: Our findings propose a novel T-cell immunotherapy that utilizes a dual strategy of starving blasts and cytotoxicity for preventing uncontrolled leukemia proliferation.

Inducible CCR2+ nonclassical monocytes mediate the regression of cancer metastasis

A major limitation of immunotherapy is the development of resistance resulting from cancer-mediated inhibition of host lymphocytes. Cancer cells release CCL2 to recruit classical monocytes expressing its receptor CCR2 for the promotion of metastasis and resistance to immunosurveillance. In the circulation, some CCR2-expressing classical monocytes lose CCR2 and differentiate into intravascular nonclassical monocytes that have anticancer properties but are unable to access extravascular tumor sites. We found that in mice and humans, an ontogenetically distinct subset of naturally underrepresented CCR2-expressing nonclassical monocytes was expanded during inflammatory states such as organ transplant and COVID-19 infection. These cells could be induced during health by treatment of classical monocytes with small-molecule activators of NOD2. The presence of CCR2 enabled these inducible nonclassical monocytes to infiltrate both intra- and extravascular metastatic sites of melanoma, lung, breast, and colon cancer in murine models, and they reversed the increased susceptibility of Nod2-/- mutant mice to cancer metastasis. Within the tumor colonies, CCR2+ nonclassical monocytes secreted CCL6 to recruit NK cells that mediated tumor regression, independent of T and B lymphocytes. Hence, pharmacological induction of CCR2+ nonclassical monocytes might be useful for immunotherapy-resistant cancers.

Comprehensive exploration on the role of base excision repair genes in modulating immune infiltration in low-grade glioma

INTRODUCTION

Glioma is a brain tumour occurring in all age groups but common in adults. Despite advances in the understanding of tumours, we cannot improve the survival of the patients and do not have an appropriate biomarker for progression and prognosis prediction. The base excision repair mechanism maintains the integrity of the genome, preventing tumour formation. However, continuous chemical damage to the cells results in mutations that escape the repair mechanism and support tumour growth. The tumour microenvironment in cancer is crucial in determining the tumour growth, development, and response to treatments. The present study explored the significance of Base Excision Repair genes (BER) in modulating the tumour microenvironment.

METHODS

We used the publically available data sets from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) to explore the role of the base excision repair gene in the modulating tumour microenvironment. The data was analysed for the expression of base excision repair genes, their correlation with the immune markers, their prognostic potential, and enrichment analysis to understand the pathways they modulate in low-grade glioma (LGG) progression.

RESULTS

The analysis showed BER genes contribute an integral role in the overall and disease-free survival of LGG. Genes like MUTYH, PNKP, UNG and XRCC1 showed a correlation with the immune infiltration levels and a significant correlation with various immune markers associated with different immune cells, including tumour-associated macrophages. MUTYH, UNG and XRCC1 correlated with IDH1 mutation status, and functional enrichment analysis showed that these genes are enriched in several pathways like Wnt, PD-1 and Integrin signalling.

CONCLUSION

Our findings suggest that the BER genes MUTYH, PNKP, UNG and XRCC1 can potentially be prognostic biomarkers and highly correlate with the immune cells of the tumour microenvironment.

Membrane-camouflaged biomimetic nanoplatform with arsenic complex for synergistic reinforcement of liver cancer therapy

Aim: Arsenic has excellent anti-advanced liver cancer effects through a variety of pathways, but its severe systemic toxicity forces the need for a safe and effective delivery strategy.Methods: Based on the chelating metal ion properties of polydopamine (PDA), arsenic was immobilized on an organic carrier, and a M1-like macrophage cell membrane (MM)-camouflaged manganese-arsenic complex mesoporous polydopamine (MnAsOx@MP@M) nanoplatform was successfully constructed. MnAsOx@MP@M was evaluated at the cellular level for tumor inhibition and tumor localization, and in vivo for its anti-liver cancer effect in a Hepa1-6 tumor-bearing mouse model.Results: The nanoplatform targeted the tumor site through the natural homing property of MM, completely degraded and released drugs to kill tumor cells in an acidic environment, while playing an immunomodulatory role in promoting tumor-associated macrophages (TAMs) repolarization.Conclusion: MnAsOx@MP@M has synergistically enhanced the targeted therapeutics against liver cancer via nanotechnology and immunotherapy, and it is expected to become a safe and multifunctional treatment platform in clinical oncology.

Molecular understanding and clinical aspects of tumor-associated macrophages in the immunotherapy of renal cell carcinoma

Renal cell carcinoma (RCC) is one of the most common tumors that afflicts the urinary system, accounting for 90-95% of kidney cancer cases. Although its incidence has increased over the past decades, its pathogenesis is still unclear. Tumor-associated macrophages (TAMs) are the most prominent immune cells in the tumor microenvironment (TME), comprising more than 50% of the tumor volume. By interacting with cancer cells, TAMs can be polarized into two distinct phenotypes, M1-type and M2-type TAMs. In the TME, M2-type TAMs, which are known to promote tumorigenesis, are more abundant than M1-type TAMs, which are known to suppress tumor growth. This ratio of M1 to M2 TAMs can create an immunosuppressive environment that contributes to tumor cell progression and survival. This review focused on the role of TAMs in RCC, including their polarization, impacts on tumor proliferation, angiogenesis, invasion, migration, drug resistance, and immunosuppression. In addition, we discussed the potential of targeting TAMs for clinical therapy in RCC. A deeper understanding of the molecular biology of TAMs is essential for exploring innovative therapeutic strategies for the treatment of RCC.

Two Different Immune Profiles Are Identified in Sentinel Lymph Nodes of Early-Stage Breast Cancer

In the management of early-stage breast cancer (BC), lymph nodes (LNs) are typically characterised using the One-Step Nucleic Acid Amplification (OSNA) assay, a standard procedure for assessing subclinical metastasis in sentinel LNs (SLNs). The pivotal role of LNs in coordinating the immune response against BC is often overlooked. Our aim was to improve prognostic information provided by the OSNA assay and explore immune-related gene signatures in SLNs. The expression of an immune gene panel was analysed in SLNs from 32 patients with Luminal A early-stage BC (cT1-T2 N0). Using an unsupervised approach based on these expression values, this study identified two clusters, regardless of the SLN invasion: one evidencing an adaptive anti-tumoral immune response, characterised by an increase in naive B cells, follicular T helper cells, and activated NK cells; and another with a more undifferentiated response, with an increase in the activated-to-resting dendritic cells (DCs) ratio. Through a protein-protein interaction (PPI) network, we identified seven immunoregulatory hub genes: CD80, CD40, TNF, FCGR3A, CD163, FCGR3B, and CCR2. This study shows that, in Luminal A early-stage BC, SLNs gene expression studies enable the identification of distinct immune profiles that may influence prognosis stratification and highlight key genes that could serve as potential targets for immunotherapy.

Dissecting the emerging role of cancer-associated adipocyte-derived cytokines in remodeling breast cancer progression

Breast cancer has been reported to transcend lung cancer as the most commonly diagnosed cancer in women all over the world. Adipocytes, serving as energy storage and endocrine cells, are the major stromal cells in the breast. Cancer-associated adipocytes (CAAs) are adjacent and dedifferentiated adipocytes located at the invasive front of human breast tumors. Adipocytes can transform into CAA phenotype with morphological and biological changes under the remodeling of breast cancer cells. CAAs play an essential role in breast cancer progression, including remodeling the tumor microenvironment (TME), regulating immunity, and interacting with breast cancer cells. CAAs possess peculiar secretomes and are accordingly capable to promote proliferation, invasiveness, angiogenesis, metastasis, immune escape, and drug resistance of breast cancer cells. There is a complex and coordinated crosstalk among CAAs, immune cells, and breast cancer cells. CAAs can release a variety of cytokines, including IL-6, IL-8, IL-1β, CCL5, CCL2, VEGF, G-CSF, IGF-1, and IGFBP, thereby promoting immune cell recruitment and macrophage polarization, and ultimately stimulating malignant behaviors in breast cancer cells. Here, we aim to provide a comprehensive description of CAA-derived cytokines, including their impact on cancer cell behaviors, immune regulation, breast cancer diagnosis, and treatment. A deeper understanding of CAA performance and interactions with specific TME cell populations will provide better strategies for cancer treatment and breast reconstruction after mastectomy.

M2-like tumor-associated macrophage-secreted CCL2 facilitates gallbladder cancer stemness and metastasis

BACKGROUND

The predominant immune cells in solid tumors are M2-like tumor-associated macrophages (M2-like TAMs), which significantly impact the promotion of epithelial-mesenchymal transition (EMT) in tumors, enhancing stemness and facilitating tumor invasion and metastasis. However, the contribution of M2-like TAMs to tumor progression in gallbladder cancer (GBC) is partially known.

METHODS

Immunohistochemistry was used to evaluate the expression of M2-like TAMs and cancer stem cell (CSC) markers in 24 pairs of GBC and adjacent noncancerous tissues from patients with GBC. Subsequently, GBC cells and M2-like TAMs were co-cultured to examine the expression of CSC markers, EMT markers, and migratory behavior. Proteomics was performed on the culture supernatant of M2-like TAMs. The mechanisms underlying the induction of EMT, stemness, and metastasis in GBC by M2-like TAMs were elucidated using proteomics and transcriptomics. GBC cells were co-cultured with undifferentiated macrophages (M0) and analyzed. The therapeutic effect of gemcitabine combined with a chemokine (C-C motif) receptor 2 (CCR2) antagonist on GBC was observed in vivo.

RESULTS

The expression levels of CD68 and CD163 in M2-like TAMs and CD44 and CD133 in gallbladder cancer stem cells (GBCSCs) were increased and positively correlated in GBC tissues compared with those in neighboring noncancerous tissues. M2-like TAMs secreted a significant amount of chemotactic cytokine ligand 2 (CCL2), which activated the MEK/extracellular regulated protein kinase (ERK) pathway and enhanced SNAIL expression after binding to the receptor CCR2 on GBC cells. Activation of the ERK pathway caused nuclear translocation of ELK1, which subsequently led to increased SNAIL expression. GBCSCs mediated the recruitment and polarization of M0 into M2-like TAMs within the GBC microenvironment via CCL2 secretion. In the murine models, the combination of a CCR2 antagonist and gemcitabine efficiently inhibited the growth of subcutaneous tumors in GBC.

CONCLUSIONS

The interaction between M2-like TAMs and GBC cells is mediated by the chemokine CCL2, which activates the MEK/ERK/ELK1/SNAIL pathway in GBC cells, promoting EMT, stemness, and metastasis. A combination of a CCR2 inhibitor and gemcitabine effectively suppressed the growth of subcutaneous tumors. Consequently, our study identified promising therapeutic targets and strategies for treating GBC.

CCL2/CCR2 Expression in Locally Advanced Prostate Cancer and Patient Long-Term Outcome: 10-Year Results from the TROG 03.04 RADAR Trial

This study investigated the prognostic value of the chemokine C-C motif ligand 2 (CCL2) and its receptor C-C motif chemokine receptor 2 (CCR2) expression in locally advanced prostate cancer treated with radiotherapy and androgen deprivation using the 10-year outcome data from the TROG 03.04 RADAR clinical trial. CCL2 and CCR2 protein expression in prostate cancer biopsies at the time of diagnosis were quantified by immunohistochemistry and digital quantification. CCR2 protein expression was detected in prostate cancer cells and was associated with prostate-specific antigen serum concentration (p = 0.045). However, neither CCL2 nor CCR2 tissue expression could predict prostate cancer progression, or other clinicopathological parameters including perineural invasion and patient outcome. In serum samples, CCL2 concentration at the time of diagnosis, as assayed by enzyme-linked immunosorbent assay, was significantly higher in patients with prostate cancer compared with benign prostatic hyperplasia (median difference 0.22 ng/mL, 95% CI, 0.17-0.30) (p < 0.0001) and normal controls (median difference 0.13 ng/mL, 95% CI, 0.13-0.17) (p < 0.0001). However, circulating CCL2 was not statistically significant as a predictor of disease progression and patient outcome. In conclusion, this study shows that although CCL2 and CCR2 are expressed in prostate cancer, with an increased level of CCL2 in the serum, neither CCL2 nor CCR2 expression has a clinical prognostic value in locally advanced prostate cancer.

Focal Adhesion Kinase and Colony Stimulating Factors: Intestinal Homeostasis and Innate Immunity Crosstalk

Thousands struggle with acute and chronic intestinal injury due to various causes. Epithelial intestinal healing is dependent on phenotypic transitions to a mobile phenotype. Focal adhesion kinase (FAK) is a ubiquitous protein that is essential for cell mobility. This phenotype change is mediated by FAK activation and proves to be a promising target for pharmaceutical intervention. While FAK is crucial for intestinal healing, new evidence connects FAK with innate immunity and the importance it plays in macrophage/monocyte chemotaxis, as well as other intracellular signaling cascades. These cascades play a part in macrophage/monocyte polarization, maturation, and inflammation that is associated with intestinal injury. Colony stimulating factors (CSFs) such as macrophage colony stimulating factor (M-CSF/CSF-1) and granulocyte macrophage colony stimulating factor (GM-CSF/CSF-2) play a critical role in maintaining homeostasis within intestinal mucosa by crosstalk capabilities between macrophages and epithelial cells. The communication between these cells is imperative in orchestrating healing upon injury. Diving deeper into these connections may allow us a greater insight into the role that our immune system plays in healing, as well as a better comprehension of inflammatory diseases of the gut.

Phosphoglycerate mutase 1 promotes breast cancer progression through inducing immunosuppressive M2 macrophages

Immunosuppressive tumor microenvironment (TME) contributes to tumor progression and causes major obstacles for cancer therapy. Phosphoglycerate mutase 1 (PGAM1) is a key enzyme involved in cancer metabolism while its role in remodeling TME remains unclear. In this study, we reported that PGAM1 suppression in breast cancer (BC) cells led to a decrease in M2 polarization, migration, and interleukin-10 (IL-10) production of macrophages. PGAM1 regulation on CCL2 expression was essential to macrophage recruitment, which further mediated by activating JAK-STAT pathway. Additionally, the CCL2/CCR2 axis was observed to participate in PGAM1-mediated immunosuppression via regulating PD-1 expression in macrophages. Combined targeting of PGAM1 and the CCL2/CCR2 axis led to a reduction in tumor growth in vivo. Furthermore, clinical validation in BC tissues indicated a positive correlation between PGAM1, CCL2 and macrophage infiltration. Our study provides novel insights into the induction of immunosuppressive TME by PGAM1 and propose a new strategy for combination therapies targeting PGAM1 and macrophages in BC.

Decoding the role of the CCL2/CCR2 axis in Alzheimer's disease and innovating therapeutic approaches: Keeping All options open

Alzheimer's disease (AD), as a neurodegenerative disorder, distresses the elderly in large numbers and is characterized by β-amyloid (Aβ) accumulation, elevated tau protein levels, and chronic inflammation. The brain's immune system is aided by microglia and astrocytes, which produce chemokines and cytokines. Nevertheless, dysregulated expression can cause hyperinflammation and lead to neurodegeneration. CCL2/CCR2 chemokines are implicated in neurodegenerative diseases exacerbating. Inflicting damage on nerves and central nervous system (CNS) cells is the function of this axis, which recruits and migrates immune cells, including monocytes and macrophages. It has been shown that targeting the CCL2/CCR2 axis may be a therapeutic option for inflammatory diseases. Using the current knowledge about the involvement of the CCL2/CCR2 axis in the immunopathogenesis of AD, this comprehensive review synthesizes existing information. It also explores potential therapeutic options, including modulation of the CCL2/CCR2 axis as a possible strategy in AD.

Extracellular vesicles as modulators of monocyte and macrophage function in tumors

The tumor microenvironment (TME) harbors several cell types, such as tumor cells, immune cells, and non-immune cells. These cells communicate through several mechanisms, such as cell-cell contact, cytokines, chemokines, and extracellular vesicles (EVs). Tumor-derived vesicles are known to have the ability to modulate the immune response. Monocytes are a subset of circulating innate immune cells and play a crucial role in immune surveillance, being recruited to tissues where they differentiate into macrophages. In the context of tumors, it has been observed that tumor cells can attract monocytes to the TME and induce their differentiation into tumor-associated macrophages with a pro-tumor phenotype. Tumor-derived EVs have emerged as essential structures mediating this process. Through the transfer of specific molecules and signaling factors, tumor-derived EVs can shape the phenotype and function of monocytes, inducing the expression of cytokines and molecules by these cells, thus modulating the TME towards an immunosuppressive environment.

The role of CCL2/CCR2 axis in cancer and inflammation: The next frontier in nanomedicine

The communication between cells and their microenvironment represents an intrinsic and essential attribute that takes place in several biological processes, including tissue homeostasis and tissue repair. Among these interactions, inflammation is certainly a central biological response that occurs through cytokines and the crosstalk with their respective receptors. In particular, the interaction between CCL2 and its main receptor, CCR2, plays a pivotal role in both harmful and protective inflammatory states, including cancer-mediated inflammation. The activation of the CCL2/CCR2 axis was shown to dictate the migration of macrophages with immune-suppressive phenotype and to aggravate the progression of different cancer types. In addition, this interaction mediates metastasis formation, further limiting the potential therapeutic outcome of anti-cancer drugs. Attempts to inhibit pharmacologically the CCL2/CCR2 axis have yet to show its anti-cancer efficacy as a single agent, but it sheds light on its role as a powerful tool to selectively alleviate pro-tumorigenic and anti-repair inflammation. In this review, we will elucidate the role of CCL2/CCR2 axis in promoting cancer inflammation by activating the host pro-tumorigenic phenotype. Moreover, we will provide some insight into the potential therapeutic benefit of targeting the CCL2/CCR2 axis for cancer and inflammation using novel delivery systems, aiming to sensitize non-responders to currently approved immunotherapies and offer new combinatory approaches.

Targeting tumor‑associated macrophages: Critical players in tumor progression and therapeutic strategies (Review)

Tumor‑associated macrophages (TAMs) are essential components of the tumor microenvironment (TME) and display phenotypic heterogeneity and plasticity associated with the stimulation of bioactive molecules within the TME. TAMs predominantly exhibit tumor‑promoting phenotypes involved in tumor progression, such as tumor angiogenesis, metastasis, immunosuppression and resistance to therapies. In addition, TAMs have the potential to regulate the cytotoxic elimination and phagocytosis of cancer cells and interact with other immune cells to engage in the innate and adaptive immune systems. In this context, targeting TAMs has been a popular area of research in cancer therapy, and a comprehensive understanding of the complex role of TAMs in tumor progression and exploration of macrophage‑based therapeutic approaches are essential for future therapeutics against cancers. The present review provided a comprehensive and updated overview of the function of TAMs in tumor progression, summarized recent advances in TAM‑targeting therapeutic strategies and discussed the obstacles and perspectives of TAM‑targeting therapies for cancers.

Gut microbiome-mediated monocytes promote liver metastasis

The gut microbiome plays an important role in tumor growth by regulating immune cell function. However, the role of the gut microbiome-mediated monocytes in liver metastasis remains unclear. In this study, we found that fecal microbiome transplantation (FMT) from the stool of patients with liver metastasis (LM) significantly promoted liver metastasis compared with healthy donors (HD). Monocytes were upregulated in liver tissues by the CCL2/CCR2 axis in LM patients' stool transplanted mouse model. CCL2/CCR2 inhibition and monocyte depletion significantly suppress liver metastasis. FMT using LM patients' stool enhanced the plasma lipopolysaccharides (LPS) concentration. The LPS/TLR4 signaling pathway is crucial for gut microbiome-mediated liver metastasis. These results indicated that monocytes contribute to liver metastasis via the CCL2/CCR2 axis.

Endolysosomal transient receptor potential mucolipins and two-pore channels: implications for cancer immunity

Past research has identified that cancer cells sustain several cancer hallmarks by impairing function of the endolysosomal system (ES). Thus, maintaining the functional integrity of endolysosomes is crucial, which heavily relies on two key protein families: soluble hydrolases and endolysosomal membrane proteins. Particularly members of the TPC (two-pore channel) and TRPML (transient receptor potential mucolipins) families have emerged as essential regulators of ES function as a potential target in cancer therapy. Targeting TPCs and TRPMLs has demonstrated significant impact on multiple cancer hallmarks, including proliferation, growth, migration, and angiogenesis both in vitro and in vivo. Notably, endosomes and lysosomes also actively participate in various immune regulatory mechanisms, such as phagocytosis, antigen presentation, and the release of proinflammatory mediators. Yet, knowledge about the role of TPCs and TRPMLs in immunity is scarce. This prompts a discussion regarding the potential role of endolysosomal ion channels in aiding cancers to evade immune surveillance and destruction. Specifically, understanding the interplay between endolysosomal ion channels and cancer immunity becomes crucial. Our review aims to comprehensively explore the current knowledge surrounding the roles of TPCs and TRPMLs in immunity, whilst emphasizing the critical need to elucidate their specific contributions to cancer immunity by pointing out current research gaps that should be addressed.

DEP domain containing 1 as a biomarker for poor prognosis in lung adenocarcinoma

Objective

The DEP domain-containing 1 (DEPDC1) gene is essential in the development and advancement of different types of cancer. This study is to examine the levels of DEPDC1 in lung adenocarcinoma (LUAD), and to determine its relationship with clinical results and immune response. The goal is to assess its potential as a biomarker and therapeutic target for LUAD.

Methods

By comprehensively utilizing the Cancer Genome Atlas (TCGA), gene Expression Synthesis (GEO), UALCAN, cBioPortal, TISIDB databases and online platforms, we conducted a bioinformatics analysis to investigate DEPDC1 gene survival analysis, prognostic diagnosis, prognostic survival, immune cell infiltration, DNA methylation, and the correlation of genetic mutations in LUAD. The results were validated through cell assay and immunohistochemical staining.

Results

DEPDC1 shows high levels of expression in the majority of tumors, with its expression being notably elevated in LUAD compablue to normal tissues. The expression of DEPDC1 varies based on the clinical characteristics of patients with LUAD. DEPDC1 expression affects the survival prognosis and prognostic model construction of LUAD patients. In addition, the presence of DEPDC1 is linked to immune infiltration. Various chemokines and chemokine receptors, immunoinhibitors and immune-stimulators in LUAD are significantly correlated with DEPDC1 methylation levels. Cell experiments confirmed through qPCR that the mRNA expression of DEPDC1 in LUAD was markedly elevated in comparison to the normal population, and immunohistochemistry showed positive DEPDC1 expression in LUAD pathological sections.

Conclusion

Systematic analysis and experiments have verified that DEPDC1 serves as a biomarker for detecting early, prediction of survival, and evaluation of immune cell infiltration in LUAD.

Do PFCAs drive the establishment of thyroid cancer microenvironment? Effects of C6O4, PFOA and PFHxA exposure in two models of human thyroid cells in primary culture

BACKGROUND

Exposure to environmental pollutants is suspected to be one of the potential causes accounting for the increase in thyroid cancer (TC) incidence worldwide. Among the ubiquitous pollutants, per-polyfluoroalkyl substances (PFASs), were demonstrated to exert thyroid disrupting effects. Perfluoroalkyl carboxylates (PFCAs) represent a subgroup of PFAS and include perfluoro carboxylic acids (PFOA and PFHxA) and perfluoropolyether carboxylic acid (C6O4). The potential relationship between exposure to PFCAs and TC was not yet fully elucidated. This in vitro study investigated whether certain PFCAs (C6O4, PFOA, and PFHxA) can influence the composition of TC microenvironment.

METHODS

Two models of normal thyroid cells in primary cultures: Adherent (A-NHT) and Spheroids (S-NHT) were employed. A-NHT and S-NHT were exposed to C6O4, PFOA or PFHxA (0; 0.01; 0.1, 1; 10; 100; 1000 ng/mL) to assess viability (WST-1 and AV/PI assay), evaluate spherification index (SI) and volume specifically in S-NHT. CXCL8 and CCL2 (mRNA and protein), and EMT-related genes were assessed in both models after exposure to PFCAs.

RESULTS

PFHxA reduced the viability of both A-NHT and S-NHT. None of the PFCAs interfered with the volume or spherification process in S-NHT. CXCL8 and CCL2 mRNA and protein levels were differently up-regulated by each PFCAs, being PFOA and PFHxA the stronger inducers. Moreover, among the tested PFCAs, PFHxA induced a more consistent increase in the mRNA levels of EMT-related genes.

CONCLUSIONS

This is the first evaluation of the effects of exposure to PFCAs on factors potentially involved in establishing the TC microenvironment. PFHxA modulated the TC microenvironment at three levels: cell viability, pro-tumorigenic chemokines, and EMT-genes. The results provide further evidence of the pro-tumorigenic effect of PFOA. On the other hand, a marginal effect was observed for C6O4 on pro-tumorigenic chemokines.

Advance in the role of chemokines/chemokine receptors in carcinogenesis: Focus on pancreatic cancer

The chemokines/chemokine receptors pathway significantly influences cell migration, particularly in recruiting immune cells to the tumor microenvironment (TME), impacting tumor progression and treatment outcomes. Emerging research emphasizes the involvement of chemokines in drug resistance across various tumor therapies, including immunotherapy, chemotherapy, and targeted therapy. This review focuses on the role of chemokines/chemokine receptors in pancreatic cancer (PC) development, highlighting their impact on TME remodeling, immunotherapy, and relevant signaling pathways. The unique immunosuppressive microenvironment formed by the interaction of tumor cells, stromal cells and immune cells plays an important role in the tumor proliferation, invasion, migration and therapeutic resistance. Chemokines/chemokine receptors, such as chemokine ligand (CCL) 2, CCL3, CCL5, CCL20, CCL21, C-X-C motif chemokine ligand (CXCL) 1, CXCL2, CXCL3, CXCL4, CXCL5, CXCL8, CXCL9, CXCL10, CXCL11, CXCL12, CXCL13, CXCL14, CXCL16, CXCL17, and C-X3-C motif chemokine ligand (CX3CL)1, derived mainly from leukocyte cells, cancer-related fibroblasts (CAFs), pancreatic stellate cells (PSCs), and tumor-associated macrophages (TAMs), contribute to PC progression and treatment resistance. Chemokines recruit myeloid-derived suppressor cells (MDSC), regulatory T cells (Tregs), and M2 macrophages, inhibiting the anti-tumor activity of immune cells. Simultaneously, they enhance pathways like epithelial-mesenchymal transition (EMT), Akt serine/threonine kinase (AKT), extracellular regulated protein kinases (ERK) 1/2, and nuclear factor kappa-B (NF-κB), etc., elevating the risk of PC metastasis and compromising the efficacy of radiotherapy, chemotherapy, and anti-PD-1/PD-L1 immunotherapy. Notably, the CCLx-CCR2 and CXCLx-CXCR2/4 axis emerge as potential therapeutic targets in PC. This review integrates recent findings on chemokines and receptors in PC treatment, offering valuable insights for innovative therapeutic approaches.

Dendritic cell-derived exosomes (Dex): Underlying the role of exosomes derived from diverse DC subtypes in cancer pathogenesis

Exosomes are nanometric membrane vesicles of late endosomal origin that are released by most, if not all, cell types as a sophisticated means of intercellular communication. They play an essential role in the movement of materials and information between cells, transport a variety of proteins, lipids, RNA, and other vital data, and over time, they become an essential part of the drug delivery system and a marker for the early detection of many diseases. Dendritic cells have generated interest in cancer immunotherapy due to their ability to initiate and modify effective immune responses. Apart from their cytokine release and direct interactions with other cell types, DCs also emit nanovesicles, such as exosomes, that contribute to their overall activity. Numerous studies have demonstrated exosomes to mediate and regulate immune responses against cancers. Dendritic cell-derived exosomes (DCs) have attracted a lot of attention as immunotherapeutic anti-cancer treatments since it was found that they contain functional MHC-peptide complexes along with a variety of other immune-stimulating components that together enable immune cell-dependent tumor rejection. By enhancing tumor and immunosuppressive immune cells or changing a pro-inflammatory milieu to inhibit tumor advancement, exosomes generated from dendritic cells can initiate and support tumor growth. This study reviewed the immunogenicity of dendritic cell-derived exosomes and strategies for expanding their immunogenic potential as novel and effective anti-cancer therapies.

MRI Detection of Lymph Node Metastasis through Molecular Targeting of C-C Chemokine Receptor Type 2 and Monocyte Hitchhiking

Biopsy is the clinical standard for diagnosing lymph node (LN) metastasis, but it is invasive and poses significant risk to patient health. Magnetic resonance imaging (MRI) has been utilized as a noninvasive alternative but is limited by low sensitivity, with only ∼35% of LN metastases detected, as clinical contrast agents cannot discriminate between healthy and metastatic LNs due to nonspecific accumulation. Nanoparticles targeted to the C-C chemokine receptor 2 (CCR2), a biomarker highly expressed in metastatic LNs, have the potential to guide the delivery of contrast agents, improving the sensitivity of MRI. Additionally, cancer cells in metastatic LNs produce monocyte chemotactic protein 1 (MCP1), which binds to CCR2+ inflammatory monocytes and stimulates their migration. Thus, the molecular targeting of CCR2 may enable nanoparticle hitchhiking onto monocytes, providing an additional mechanism for metastatic LN targeting and early detection. Hence, we developed micelles incorporating gadolinium (Gd) and peptides derived from the CCR2-binding motif of MCP1 (MCP1-Gd) and evaluated the potential of MCP1-Gd to detect LN metastasis. When incubated with migrating monocytes in vitro, MCP1-Gd transport across lymphatic endothelium increased 2-fold relative to nontargeting controls. After administration into mouse models with initial LN metastasis and recurrent LN metastasis, MCP1-Gd detected metastatic LNs by increasing MRI signal by 30-50% relative to healthy LNs. Furthermore, LN targeting was dependent on monocyte hitchhiking, as monocyte depletion decreased accumulation by >70%. Herein, we present a nanoparticle contrast agent for MRI detection of LN metastasis mediated by CCR2-targeting and demonstrate the potential of monocyte hitchhiking for enhanced nanoparticle delivery.

Traversing through the Mechanistic Event Analysis in IL-6 and IL-17 Signaling for a New Therapeutic Paradigm in NSCLC

IL-6 and IL-17 are paradoxical cytokines that progress inflammatory states in chronic diseases, including cancer. In lung cancer, their role has been elucidated to favor cancer development by modulating signaling mechanisms critical to cellular growth. The intrinsic ability of these cytokines to influence macroautophagy is yet another reason to facilitate lung cancer. Here, we employed a systems immunology approach to discover the mechanistic role of these cytokines in cancer development. In a biological system, at later stages, the activation of NFkB stimulates immunosuppressive phenotypes to achieve tolerating effects in a transformed cell. We found that the upregulation of cytokines signaled M2 macrophages to modulate tumor responses through the activation of autophagic intermediates and inflammasome mediators. This caused immune perturbations in the tumor microenvironment, which were associated with cancer inflammation. To address these inflammatory states, we performed triggered event analysis to examine whether overexpressing immune effectors or downregulating immune suppressors may have an effect on cancer reversal. Interestingly, the inhibition of immune regulators opposed the model outcome to an increased immune response. Therefore, IL6-IL17-mediated regulation of lung cancer may address tumor malignancy and potentiate the development of newer therapeutics for NSCLC.

Integrative analysis reveals chemokines CCL2 and CXCL5 mediated shear stress-induced aortic dissection formation

Background

Aortic dissection (AD) is a critical emergency in cardiovascular disease. AD occurs only in specific sites of the aorta, and the variation of shear stress in different aortic segments is a possible cause not reported. This study investigated the key molecules involved in shear stress-induced AD through quantitative bioinformatic analysis of a public RNA sequencing database and clinical tissue sample validation.

Methods

Gene expression data from the GSE153434, GSE147026, and GSE52093 datasets were downloaded from the Gene Expression Omnibus. Next, differently expressed genes (DEGs) in each dataset were identified and integrated to identify common AD DEGs. STRING, Cytoscape, and MCODE were used to identify hub genes and crucial clustering modules, and Connectivity Map (CMap) was used to identify positive and negative agents. The same procedure was performed for the GSE160611 dataset to obtain shear stress-induced human aortic endothelial cell (HAEC) DEGs. After the integration of these two DEGs sets to identify shear stress-associated hub DEGs in AD, Gene Ontology Enrichment Analysis was performed. The common chemokine receptors and ligands in AD were identified by analyzing AD's three RNA sequencing datasets. Their origin was verified by analyzing AD single-cell sequencing data and validated by immunoblotting and immunofluorescence.

Results

We identified 100 down-regulated and 50 up-regulated AD common DEGs. Enrichment results showed that common DEGs were closely related to blood vessel morphogenesis, muscle structure development, muscle tissue development, and chemotaxis. Among those DEGs, MYC, CCL2, and SPP1 are the three molecules with the highest degree. A crucial cluster of 15 genes was identified using MCODE, which contained inflammation-related genes with elevated expression and muscle cell-related genes with decreased expression, and CCL2 is central to immune-related genes. CMap confirmed MEK inhibitors and ALK inhibitors as possible therapeutic agents for AD. Moreover, 366 shear stress-associated DEGs in HAEC were identified in the GSE160611 dataset. After taking the intersection, we identified five shear stress-associated hub DEGs in AD (ANGPTL4, SNAI2, CCL2, GADD45B, and PROM1), and the enrichment analysis indicated they were related to the endothelial cell apoptotic process. Chemokine CCL2 was the molecule with a high degree in both DEG sets. Besides CCL2, CXCL5 was the only chemokine ligand differentially expressed in the three datasets. Additionally, immunoblotting confirmed the increased expression of CCL2 and CXCL5 in clinical tissue samples. Further research at the single-cell level revealed that CCL2 has multiple origins, and CXCL5 is macrophage-derived.

Conclusion

Through integrative analysis, we identified core common AD DEGs and possible therapeutic agents based on these DEGs. We elucidated that the chemokine CCL2 and CXCL5-mediated "Endothelial-Monocyte-Neutrophil" axis may contribute to the development of shear stress-induced AD. These findings provide possible therapeutic targets for the prevention and treatment of AD.

Obesity modulates the cellular and molecular microenvironment in the peritoneal cavity: implication for ovarian cancer risk

Introduction

Abdominal obesity increases the risk of developing ovarian cancer but the molecular mechanisms of how obesity supports ovarian cancer development remain unknown. Here we investigated the impact of obesity on the immune cell and gene expression profiles of distinct abdominal tissues, focusing on the peritoneal serous fluid (PSF) and the omental fat band (OFB) as critical determinants for the dissemination of ovarian metastases and early metastatic events within the peritoneal cavity.

Methods

Female C57BL/6 mice were fed a low-fat (LFD) or a high-fat diet (HFD) for 12 weeks until the body weights in the HFD group were significantly higher and the mice displayed an impaired glucose tolerance. Then the mice were injected with the murine ovarian cancer cells (MOSE-LTICv) while remaining on their diets. After 21 days, the mice were sacrificed, tumor burden was evaluated and tissues were harvested. The immune cell composition of abdominal tissues and changes in gene expression in the PSF and OFB were evaluated by flow cytometry and qPCR RT2-profiler PCR arrays and confirmed by qRT-PCR, respectively. Other peritoneal adipose tissues including parametrial and retroperitoneal white adipose tissues as well as blood were also investigated.

Results

While limited effects were observed in the other peritoneal adipose tissues, feeding mice the HFD led to distinct changes in the immune cell composition in the PSF and the OFB: a depletion of B cells but an increase in myeloid-derived suppressor cells (MDSC) and mono/granulocytes, generating pro-inflammatory environments with increased expression of cyto- and chemokines, and genes supporting adhesion, survival, and growth, as well as suppression of apoptosis. This was associated with a higher peritoneal tumor burden compared to mice fed a LFD. Changes in cellular and genetic profiles were often exacerbated by the HFD. There was a large overlap in genes that were modulated by both the HFD and the cancer cells, suggesting that this 'genetic fingerprint' is important for ovarian metastases to the OFB.

Discussion

In accordance with the 'seed and soil' theory, our studies show that obesity contributes to the generation of a pro-inflammatory peritoneal environment that supports the survival of disseminating ovarian cancer cells in the PSF and the OFB and enhances the early metastatic adhesion events in the OFB through an increase in extracellular matrix proteins and modulators such as fibronectin 1 and collagen I expression as well as in genes supporting growth and invasion such as Tenacin C. The identified genes could potentially be used as targets for prevention strategies to lower the ovarian cancer risk in women with obesity.

Angiogenesis and Pancreatic Cancer: Novel Approaches to Overcome Treatment Resistance

Pancreatic cancer (PCa) is acknowledged as a significant contributor to global cancer- related mortality and is widely recognized as one of the most challenging malignant diseases to treat. Pancreatic ductal adenocarcinoma (PDAC), which is the most common type of PCa, is highly aggressive and is mostly incurable. The poor prognosis of this neoplasm is exacerbated by the prevalence of angiogenic molecules, which contribute to stromal stiffness and immune escape. PDAC overexpresses various proangiogenic proteins, including vascular endothelial growth factor (VEGF)-A, and the levels of these molecules correlate with poor prognosis and treatment resistance. Moreover, VEGF-targeting anti-angiogenesis treatments are associated with the onset of resistance due to the development of hypoxia, which in turn induces the production of angiogenic molecules. Furthermore, excessive angiogenesis is one of the hallmarks of the second most common form of PCa, namely, pancreatic neuroendocrine tumor (PNET). In this review, the role of angiogenesis regulators in promoting disease progression in PCa, and the impact of these molecules on resistance to gemcitabine and various therapies against PCa are discussed. Finally, the use of anti-angiogenic agents in combination with chemotherapy and other targeted therapeutic molecules is discussed as a novel solution to overcome current treatment limitations in PCa.

Immune Evasion in Cancer Is Regulated by Tumor-Asociated Macrophages (TAMs): Targeting TAMs

Recent advancements in cancer treatment have explored a variety of approaches to address the needs of patients. Recently, immunotherapy has evolved as an efficacious treatment for various cancers resistant to conventional therapies. Hence, significant milestones in immunotherapy were achieved clinically in a large subset of cancer patients. Unfortunately, some cancer types do not respond to treatment, and among the responsive cancers, some patients remain unresponsive to treatment. Consequently, there is a critical need to examine the mechanisms of immune resistance and devise strategies to target immune suppressor cells or factors, thereby allowing for tumor sensitivity to immune cytotoxic cells. M2 macrophages, also known as tumor-associated macrophages (TAMs), are of interest due to their role in suppressing the immune system and influencing antitumor immune responses through modulating T cell activity and immune checkpoint expression. TAMs are associated with signaling pathways that modulate the tumor microenvironment (TME), contributing to immune evasion. One approach targets TAMs, focusing on preventing the polarization of M1 macrophages into the protumoral M2 phenotype. Other strategies focus on direct or indirect targeting of M2 macrophages through understanding the interaction of TAMs with immune factors or signaling pathways. Clinically, biomarkers associated with TAMs' immune resistance in cancer patients have been identified, opening avenues for intervention using pharmacological agents or immunotherapeutic approaches. Ultimately, these multifaceted approaches are promising in overcoming immune resistance and improving cancer treatment outcomes.

A Novel Gene Signature based on Immune Cell Infiltration Landscape Predicts Prognosis in Lung Adenocarcinoma Patients

BACKGROUND

The tumor microenvironment (TME) is created by the tumor and dominated by tumor-induced interactions. Long-term survival of lung adenocarcinoma (LUAD) patients is strongly influenced by immune cell infiltration in TME. The current article intends to construct a gene signature from LUAD ICI for predicting patient outcomes.

METHODS

For the initial phase of the study, the TCGA-LUAD dataset was chosen as the training group for dataset selection. We found two datasets named GSE72094 and GSE68465 in the Gene Expression Omnibus (GEO) database for model validation. Unsupervised clustering was performed on the training cohort patients using the ICI profiles. We employed Kaplan-Meier estimators and univariate Cox proportional-hazard models to identify prognostic differentially expressed genes in immune cell infiltration (ICI) clusters. These prognostic genes are then used to develop a LASSO Cox model that generates a prognostic gene signature. Validation was performed using Kaplan-Meier estimation, Cox, and ROC analysis. Our signature and vital immune-relevant signatures were analyzed. Finally, we performed gene set enrichment analysis (GSEA) and immune infiltration analysis on our finding gene signature to further examine the functional mechanisms and immune cellular interactions.

RESULTS

Our study found a sixteen-gene signature (EREG, HPGDS, TSPAN32, ACSM5, SFTPD, SCN7A, CCR2, S100P, KLK12, MS4A1, INHA, HOXB9, CYP4B1, SPOCK1, STAP1, and ACAP1) to be prognostic based on data from the training cohort. This prognostic signature was certified by Kaplan-Meier, Cox proportional-hazards, and ROC curves. 11/15 immune-relevant signatures were related to our signature. The GSEA results indicated our gene signature strongly correlates with immune-related pathways. Based on the immune infiltration analysis findings, it can be deduced that a significant portion of the prognostic significance of the signature can be attributed to resting mast cells.

CONCLUSION

We used bioinformatics to determine a new, robust sixteen-gene signature. We also found that this signature's prognostic ability was closely related to the resting mast cell infiltration of LUAD patients.

Emerging Immunotherapy Approaches for Advanced Clear Cell Renal Cell Carcinoma

The most common subtype of renal cell carcinoma is clear cell renal cell carcinoma (ccRCC). While localized ccRCC can be cured with surgery, metastatic disease has a poor prognosis. Recently, immunotherapy has emerged as a promising approach for advanced ccRCC. This review provides a comprehensive overview of the evolving immunotherapeutic landscape for metastatic ccRCC. Immune checkpoint inhibitors (ICIs) like PD-1/PD-L1 and CTLA-4 inhibitors have demonstrated clinical efficacy as monotherapies and in combination regimens. Combination immunotherapies pairing ICIs with antiangiogenic agents, other immunomodulators, or novel therapeutic platforms such as bispecific antibodies and chimeric antigen receptor (CAR) T-cell therapy are areas of active research. Beyond the checkpoint blockade, additional modalities including therapeutic vaccines, cytokines, and oncolytic viruses are also being explored for ccRCC. This review discusses the mechanisms, major clinical trials, challenges, and future directions for these emerging immunotherapies. While current strategies have shown promise in improving patient outcomes, continued research is critical for expanding and optimizing immunotherapy approaches for advanced ccRCC. Realizing the full potential of immunotherapy will require elucidating mechanisms of response and resistance, developing predictive biomarkers, and rationally designing combination therapeutic regimens tailored to individual patients. Advances in immunotherapy carry immense promise for transforming the management of metastatic ccRCC.

Patient-Specific Vascularized Tumor Model: Blocking TAM Recruitment with Multispecific Antibodies Targeting CCR2 and CSF-1R

Tumor-associated inflammation drives cancer progression and therapy resistance, with the infiltration of monocyte-derived tumor-associated macrophages (TAMs) associated with poor prognosis in diverse cancers. Targeting TAMs holds potential against solid tumors, but effective immunotherapies require testing on immunocompetent human models prior to clinical trials. Here, we develop an in vitro model of microvascular networks that incorporates tumor spheroids or patient tissues. By perfusing the vasculature with human monocytes, we investigate monocyte trafficking into the tumor and evaluate immunotherapies targeting the human tumor microenvironment. Our findings demonstrate that macrophages in vascularized breast and lung tumor models can enhance monocyte recruitment via TAM-produced CCL7 and CCL2, mediated by CSF-1R. Additionally, we assess a novel multispecific antibody targeting CCR2, CSF-1R, and neutralizing TGF-β, referred to as CSF1R/CCR2/TGF-β Ab, on monocytes and macrophages using our 3D models. This antibody repolarizes TAMs towards an anti-tumoral M1-like phenotype, reduces monocyte chemoattractant protein secretion, and effectively blocks monocyte migration. Finally, we show that the CSF1R/CCR2/TGF-β Ab inhibits monocyte recruitment in patient-specific vascularized tumor models. Overall, this vascularized tumor model offers valuable insights into monocyte recruitment and enables functional testing of innovative therapeutic antibodies targeting TAMs in the tumor microenvironment (TME).

Targeting TREM1 augments antitumor T cell immunity by inhibiting myeloid-derived suppressor cells and restraining anti-PD-1 resistance

The triggering receptor expressed on myeloid cell 1 (TREM1) plays a critical role in development of chronic inflammatory disorders and the inflamed tumor microenvironment (TME) associated with most solid tumors. We examined whether loss of TREM1 signaling can abrogate the immunosuppressive TME and enhance cancer immunity. To investigate the therapeutic potential of TREM1 in cancer, we used mice deficient in Trem1 and developed a novel small molecule TREM1 inhibitor, VJDT. We demonstrated that genetic or pharmacological TREM1 silencing significantly delayed tumor growth in murine melanoma (B16F10) and fibrosarcoma (MCA205) models. Single-cell RNA-Seq combined with functional assays during TREM1 deficiency revealed decreased immunosuppressive capacity of myeloid-derived suppressor cells (MDSCs) accompanied by expansion in cytotoxic CD8+ T cells and increased PD-1 expression. Furthermore, TREM1 inhibition enhanced the antitumorigenic effect of anti-PD-1 treatment, in part, by limiting MDSC frequency and abrogating T cell exhaustion. In patient-derived melanoma xenograft tumors, treatment with VJDT downregulated key oncogenic signaling pathways involved in cell proliferation, migration, and survival. Our work highlights the role of TREM1 in cancer progression, both intrinsically expressed in cancer cells and extrinsically in the TME. Thus, targeting TREM1 to modify an immunosuppressive TME and improve efficacy of immune checkpoint therapy represents what we believe to be a promising therapeutic approach to cancer.

Role of MCP-1/CCR2 axis in renal fibrosis: Mechanisms and therapeutic targeting

Renal fibrosis is a common pathological manifestation in various chronic kidney diseases. Inflammation plays a central role in renal fibrosis development. Owing to their significant participation in inflammation and autoimmunity, chemokines have always been the hot spot and focus of scientific research and clinical intervention. Among the chemokines, monocyte chemoattractant protein-1 (MCP-1), also known as C-C motif chemokine ligand 2, together with its main receptor C-C chemokine receptor type 2 (CCR2) are important chemokines in renal fibrosis. The MCP-1/CCR2 axis is activated when MCP-1 binds to CCR2. Activation of MCP-1/CCR2 axis can induce chemotaxis and activation of inflammatory cells, and initiate a series of signaling cascades in renal fibrosis. It mediates and promotes renal fibrosis by recruiting monocyte, promoting the activation and transdifferentiation of macrophages. This review summarizes the complex physical processes of MCP-1/CCR2 axis in renal fibrosis and addresses its general mechanism in renal fibrosis by using specific examples, together with the progress of targeting MCP-1/CCR2 in renal fibrosis with a view to providing a new direction for renal fibrosis treatment.

Systematic Pan-Cancer Analysis Reveals X-C Motif Chemokine Receptor 1 as a Prognostic and Immunological Biomarker

Chemokines and their receptors play an important role in immune monitoring and immune defense during tumor growth and metastasis. However, their prognostic roles in pan-cancer have not been elucidated. In this work, we screened all chemokine receptors in pan-cancer and discovered X-C Motif Chemokine Receptor 1 (XCR1) as a reliable immunological and prognostic biomarker in pan-cancer using bioinformation. The TCGA database served as the foundation for the primary research database analysis in this work. XCR1 was downregulated in tumors. Patients with reduced XCR1 showed worse prognoses and a concomitant decrease in immune cell infiltration (DCs and CD8+ T cells). According to a gene enrichment study, XCR1 enhanced immune system performance by promoting T-cell infiltration through the C-X-C Motif Chemokine Ligand 9 (CXCL9)- C-X-C Motif Chemokine Receptor 3 (CXCR3) axis. In addition, XCR1 is mainly expressed in infiltrated DCs and some malignant cells in tumor tissues. Our data revealed the important role of XCR1 in remodeling the tumor microenvironment and predicting the survival prognosis, which could also be used as a sensitive biomarker for tumor immunotherapy.

Unveiling the Immune Microenvironment's Role in Breast Cancer: A Glimpse into Promising Frontiers

Breast cancer (BC), one of the most widespread and devastating diseases affecting women worldwide, presents a significant public health challenge. This review explores the emerging frontiers of research focused on deciphering the intricate interplay between BC cells and the immune microenvironment. Understanding the role of the immune system in BC is critical as it holds promise for novel therapeutic approaches and precision medicine strategies. This review delves into the current literature regarding the immune microenvironment's contribution to BC initiation, progression, and metastasis. It examines the complex mechanisms by which BC cells interact with various immune cell populations, including tumor-infiltrating lymphocytes (TILs) and tumor-associated macrophages (TAMs). Furthermore, this review highlights the impact of immune-related factors, such as cytokines and immune checkpoint molecules. Additionally, this comprehensive analysis sheds light on the potential biomarkers associated with the immune response in BC, enabling early diagnosis and prognostic assessment. The therapeutic implications of targeting the immune microenvironment are also explored, encompassing immunotherapeutic strategies and combination therapies to enhance treatment efficacy. The significance of this review lies in its potential to pave the way for novel therapeutic interventions, providing clinicians and researchers with essential knowledge to design targeted and personalized treatment regimens for BC patients.

Chemokine Ligand 2 Promotes Migration in Osteosarcoma by Regulating the miR-3659/MMP-3 Axis

Osteosarcoma is a common malignant tumor in children and adolescents, known for its aggressive invasion and distant metastasis, leading to a poor prognosis. Matrix metalloproteinases (MMPs) can degrade the extracellular matrix and basement membranes through their proteolytic activity, thereby promoting osteosarcoma metastasis. Chemokine ligand 2 (CCL2) is a well-studied chemokine that plays a significant role in the cell motility of many cancers. However, its specific involvement in osteosarcoma metastasis is not fully understood. The aim of this study is to examine the role of miRNAs in CCL2-mediated MMP expression and cell motility in human osteosarcoma. The analysis of immunohistochemistry data and databases associated a positive correlation between CCL2 or MMP-3 levels with the metastasis of osteosarcoma patients. The in vivo lung metastatic osteosarcoma model also demonstrated similar effects, showing higher levels of CCL2 and MMP-3 in lung metastatic osteosarcoma tissues. The stimulation of osteosarcoma cells with CCL2 enhanced migration and invasion abilities through the upregulation of MMP-3 synthesis. Our results also indicate that CCL2 enhances MMP-3-dependent cell motility by inhibiting miR-3659 synthesis. Therefore, CCL2 represents a promising therapeutic target for treating metastasis in osteosarcoma.

Suppression of the antitumoral activity of natural killer cells under indirect coculture with cancer-associated fibroblasts in a pancreatic TIME-on-chip model

BACKGROUND

Recently, natural killer (NK) cells emerged as a treatment option for various solid tumors. However, the immunosuppressive tumor immune microenvironment (TIME) can reduce the cytotoxic ability of NK cells in pancreatic ductal adenocarcinoma. Cancer-associated fibroblasts within the tumor stroma can suppress immune surveillance by dysregulating factors involved in the cellular activity of NK cells. Herein, the effect of activated pancreatic stellate cells (aPSCs) on NK cell-mediated anticancer efficacy under three-dimensional (3D) coculture conditions was investigated.

METHODS

3D cocultures of PANC-1 tumor spheroids (TSs) with aPSCs and NK-92 cells in a collagen matrix were optimized to identify the occurring cellular interactions and differential cytokine profiles in conditioned media using microchannel chips. PANC-1 TSs and aPSCs were indirectly cocultured, whereas NK-92 cells were allowed to infiltrate the TS channel using convective medium flow.

RESULTS

Coculture with aPSCs promoted PANC-1 TSs growth and suppressed the antitumor cytotoxic effects of NK-92 cells. Mutual inhibition of cellular activity without compromising migration ability was observed between aPSCs and NK-92 cells. Moreover, the reduced killing activity of NK-92 cells was found to be related with reduced granzyme B expression in NK cells.

CONCLUSIONS

Herein, a novel TIME-on-chip model based on the coculture of PANC-1 TSs, aPSCs, and NK-92 cells was described. This model may be useful for studying the detailed mechanisms underlying NK cells dysregulation and for exploring future therapeutic interventions to restore NK cell activity in the tumor microenvironment.

Single-cell profiling of murine bladder cancer identifies sex-specific transcriptional signatures with prognostic relevance

Bladder cancer (BLCA) is more common in men but more aggressive in women. Sex-based differences in cancer biology are commonly studied using a murine model with BLCA generated by N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN). While tumors in the BBN model have been profiled, these profiles provide limited information on the tumor microenvironment. Here, we applied single-cell RNA sequencing to characterize cell-type specific transcriptional differences between male and female BBN-induced tumors. We found proportional and gene expression differences in epithelial and non-epithelial subpopulations between male and female tumors. Expression of several genes predicted sex-specific survival in several human BLCA datasets. We identified novel and clinically relevant sex-specific transcriptional signatures including immune cells in the tumor microenvironment and it validated the relevance of the BBN model for studying sex differences in human BLCA. This work highlights the importance of considering sex as a biological variable in the development of new and accurate cancer markers.

Tryptophan Modulation in Cancer-Associated Cachexia Mouse Models

Cancer cachexia is a multifactorial syndrome that interferes with treatment and reduces the quality of life and survival of patients. Currently, there is no effective treatment or biomarkers, and pathophysiology is not clear. Our group reported alterations on tryptophan metabolites in cachectic patients, so we aim to investigate the role of tryptophan using two cancer-associated cachexia syngeneic murine models, melanoma B16F10, and pancreatic adenocarcinoma that is KPC-based. Injected mice showed signs of cancer-associated cachexia as reduction in body weight and raised spleen weight, MCP1, and carbonilated proteins in plasma. CRP and Myostatin also increased in B16F10 mice. Skeletal muscle showed a decrease in quadriceps weight and cross-sectional area (especially in B16F10). Higher expression of atrophy genes, mainly Atrogin1, was also observed. Plasmatic tryptophan levels in B16F10 tumor-bearing mice decreased even at early steps of tumorigenesis. In KPC-injected mice, tryptophan fluctuated but were also reduced and in cachectic patients were significantly lower. Treatment with 1-methyl-tryptophan, an inhibitor of tryptophan degradation, in the murine models resulted in the restoration of plasmatic tryptophan levels and an improvement on splenomegaly and carbonilated proteins levels, while changes in plasmatic inflammatory markers were mild. After the treatment, CCR2 expression in monocytes diminished and lymphocytes, Tregs, and CD8+, were activated (seen by increased in CD127 and CD25 expression, respectively). These immune cell changes pointed to an improvement in systemic inflammation. While treatment with 1-MT did not show benefits in terms of muscle wasting and atrophy in our experimental setting, muscle functionality was not affected and central nuclei fibers appeared, being a feature of regeneration. Therefore, tryptophan metabolism pathway is a promising target for inflammation modulation in cancer-associated cachexia.

Macrophages as Promising Carriers for Nanoparticle Delivery in Anticancer Therapy

Macrophages play a critical role in the immune response due to their ability to recognize and remove pathogens, as well as present antigens, which are involved in inflammation, but they are also one of the most abundant immune cell populations present in the tumor microenvironment. In recent years, macrophages have become promising cellular carriers for drug and nanoparticle delivery to the tumor microenvironment, mainly due to their natural properties such as biocompatibility, degradability, lack of immunogenicity, long half-life in circulation, crossing biological barriers, and the possibility of migration and accumulation at a site of inflammation such as a tumor. For the effectiveness of this therapeutic strategy, known as "Trojan horse", it is important that the nanoparticles engulfed by macrophages do not affect their proper functioning. In our review, we discussed how the size, shape, chemical and mechanical properties of nanoparticles influence their internalization by macrophages. In addition, we described the promising research utilizing macrophages, their cell membranes and macrophage-derived exosomes as drug carriers in anticancer therapy. As a prospect of the wider use of this therapeutic strategy, we postulate its future application in boron delivery to the tumor environment in boron neutron capture therapy.

Cancer-associated mesothelial cells are regulated by the anti-Müllerian hormone axis

Cancer-associated mesothelial cells (CAMCs) in the tumor microenvironment are thought to promote growth and immune evasion. We find that, in mouse and human ovarian tumors, cancer cells express anti-Müllerian hormone (AMH) while CAMCs express its receptor AMHR2, suggesting a paracrine axis. Factors secreted by cancer cells induce AMHR2 expression during their reprogramming into CAMCs in mouse and human in vitro models. Overexpression of AMHR2 in the Met5a mesothelial cell line is sufficient to induce expression of immunosuppressive cytokines and growth factors that stimulate ovarian cancer cell growth in an AMH-dependent way. Finally, syngeneic cancer cells implanted in transgenic mice with Amhr2-/- CAMCs grow significantly slower than in wild-type hosts. The cytokine profile of Amhr2-/- tumor-bearing mice is altered and their tumors express less immune checkpoint markers programmed-cell-death 1 (PD1) and cytotoxic T lymphocyte-associated protein 4 (CTLA4). Taken together, these data suggest that the AMH/AMHR2 axis plays a critical role in regulating the pro-tumoral function of CAMCs in ovarian cancer.

Liver Cell Type-Specific Targeting by Nanoformulations for Therapeutic Applications

Hepatocytes exert pivotal roles in metabolism, protein synthesis and detoxification. Non-parenchymal liver cells (NPCs), largely comprising macrophages, dendritic cells, hepatic stellate cells and liver sinusoidal cells (LSECs), serve to induce immunological tolerance. Therefore, the liver is an important target for therapeutic approaches, in case of both (inflammatory) metabolic diseases and immunological disorders. This review aims to summarize current preclinical nanodrug-based approaches for the treatment of liver disorders. So far, nano-vaccines that aim to induce hepatitis virus-specific immune responses and nanoformulated adjuvants to overcome the default tolerogenic state of liver NPCs for the treatment of chronic hepatitis have been tested. Moreover, liver cancer may be treated using nanodrugs which specifically target and kill tumor cells. Alternatively, nanodrugs may target and reprogram or deplete immunosuppressive cells of the tumor microenvironment, such as tumor-associated macrophages. Here, combination therapies have been demonstrated to yield synergistic effects. In the case of autoimmune hepatitis and other inflammatory liver diseases, anti-inflammatory agents can be encapsulated into nanoparticles to dampen inflammatory processes specifically in the liver. Finally, the tolerance-promoting activity especially of LSECs has been exploited to induce antigen-specific tolerance for the treatment of allergic and autoimmune diseases.

Promising Modulatory Effects of Cenicriviroc on the Progression of Mouse Colorectal Cancer through Inhibition of CCR2_CCL2 Signaling Pathway

The study was designed to assay the efficacy of cenicriviroc (CVC) on the progression of mouse colorectal cancer by downregulation of CCR2_CCL2. In this study, CVC was used to inhibit the CCR2 receptor. Next, an MTT assay was performed to evaluate the cytotoxic effects of CVC on the CT26 cell line. CT26 cells were implanted subcutaneously in BALB/c mice. After tumor implantation, one group of animals received 20 mg/kg of CVC several times. The mRNA levels of CCR2, CCL2, VEGF, NF-κB, c-Myc, vimentin, and IL33 were determined in the CT26 cell line and then tumor tissues (after 21 days), by qRT-PCR. Protein levels of the above-mentioned targets were determined by western blot and ELISA. Flow cytometry was performed to assess the changes in apoptosis. Tumor growth inhibition was measured on the 1st, 7th, and 21st days after the first treatment. In both cell line and tumor cells treated with CVC, expression levels of the markers of our interest in mRNA and protein levels were significantly reduced compared to controls. A significantly higher apoptotic index was observed in CVC-treated groups. The rates of tumor growth were significantly decreased on the 7th and 21st days after the first injection. To our knowledge, this was the first time that we demonstrated the promising effect of CVC on the development of CRC through inhibition of the CCR2_CCL2 signaling and its downstream biomarkers.