The role of NFATc1/c-myc/PKM2/IL-10 axis in activating cervical cancer tumor-associated M2 macrophage polarization to promote cervical cancer progression

Active Substances from the Micro-Immunotherapy Medicine 2LC1® Show In Vitro Anti-Cancer Properties in Colon, Prostate, and Breast Cancer Models and Immune-Enhancing Capabilities in Human Macrophages

Tumor-associated macrophages (TAMs) play a pivotal role in cancer regulation by influencing tumor growth, metastasis, and the immune microenvironment. By providing low doses and ultra-low doses (ULD) of immune regulators to the organism, micro-immunotherapy (MI) medicines (MIM) could be seen as valuable adjuvant drugs in the context of a wide range of pathological conditions, including cancers. Thus, these MIM could target TAMs, affecting their phenotype and activities. In this study, the anti-tumor and the immune-stimulatory effects of four capsules out of the ten composing the Labo'life's MIM 2LC1® (2LC1-1, 2LC1-6, 2LC1-7, and 2LC1-8), as well as the specific nucleic acid (SNA®) sequence SNA-MYC present at ULD in this medicine have been evaluated in vitro, in several cancer models, and in human monocyte-derived macrophages. Our results showed that the tested MI formulations increased the tumor cell death of spheroids from HCT-116 colon cancer cells, while reducing the spheroid volume. Moreover, the treatments impaired the clonogenic capabilities of two cancer cell lines from epithelial origin, the LNCaP prostate cancer and the MCF-7 breast cancer cells. Interestingly, ULD of the SNA-MYC shared similar anti-cancer capabilities in those models, and it led to a significant reduction in the expression of C-MYC when evaluated in a model of human M2 macrophages. In the same model, the MI formulations also increased the expression of CD86 and HLA-DR, two markers of M1 anti-tumor macrophages. In addition, the tested items modulated the secretion of a panel of chemokines related to macrophage activity and immune cell recruitment. Finally, our results showed that 2LC1-8 increased the phagocytosis capabilities of human monocyte-derived macrophages, thus possibly contributing to sustaining the immune functions of M1, which are crucial in the context of cancer. Even if more research is needed to uncover their exact mechanism of action, these results suggest that the tested capsules of 2LC1 as well as ULD of SNA-MYC display both anti-tumor and immune-enhancing effects.

Phillygenin regulates the colorectal cancer tumor microenvironment by inhibiting hypoxia-inducible factor 1 alpha

The tumor microenvironment (TME) is important in the recurrence and metastasis of colorectal cancer (CRC). Phillygenin is an effective component of Forsythiae fructus that has long been used in cancer therapy. The mechanism by which phillygenin regulates the TME remains unknown. Methods and Results: A co-culture system of CRC cells and Jurkat T cells was used to simulate the TME in vitro. Network pharmacology and Human XL cytokine arrays were used to preliminarily evaluate the role of phillygenin in the TME. The target of phillygenin was determined using transfection of plasmid-producing overexpression of hypoxia-inducible factor 1 alpha (HIF-1α) overexpression or abrogated HIF-1α expression via short hairpin RNA plasmid. The therapeutic effect of phillygenin in vivo was assessed in a subcutaneous tumor mouse model. In vitro, phillygenin enhanced the immune response of T cells and prevented the immune escape of cancer cells via the inhibition of HIF-1α. Phillygenin upregulated interleukin (IL)-2 and downregulates IL-10 and FOXP3 in Jurkat T cells co-cultured with CRC cells. Phillygenin inhibited expressions of HIF-1α, transforming growth factor-beta, vascular endothelial growth factor, and CD31 in CRC cells cultured alone or with Jurkat T cells. Phillygenin considerably suppressed tumor growth and improved the TME in vivo. Conclusions: Phillygenin can enhance the immune response and inhibit angiogenesis in the TME in CRC by inhibiting HIF-1α.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10616-024-00679-2.

The role and research progress of tumor-associated macrophages in cervical cancer

Tumor-associated macrophages (TAMs) are important immune cells in the tumor micro-environment (TME) and play a key role in the occurrence and development of cervical cancer. Besides, targeting TAMs can significantly inhibit cervical cancer tumor growth, invasion, metastasis, and angiogenesis as well as affect immune regulation. This review summarizes the correlation between TAM and tumors, the mechanism of action of TAM in cervical cancer, and the potential application of TAM in the treatment of cervical cancer. Therefore, this study may provide new ideas and targets for the development of further treatment strategies for cervical cancer patients.

Nuclear Factor of Activated T Cells (NFAT) Proteins as Targeted Molecules in Diseases: A Narrative Review

The nuclear factor of activated T cells (NFAT) is a key player in the NFAT pathway, regulating various cellular processes physiologically and pathologically. NFAT signaling is implicated in developing multiple diseases, such as cancer progression, that are associated with angiogenesis. Despite numerous studies on NFAT, there is still a dearth of information on the proteins and signaling pathway compared to other established pathways. With five NFAT proteins in the spotlight, this review aims to update the understanding of their roles and signaling by analyzing the most recent studies on the NFAT pathway. The recent insights into NFAT proteins and their association with diseases enhance our understanding of these proteins and open the possibility of developing therapeutic strategies for such diseases.

Structural elucidation of a capsular polysaccharide from Bacteroides uniformis and its ameliorative impact on DSS-induced colitis in mice

Capsular polysaccharides derived from Bacteroides species have emerged as potential mitigators of intestinal inflammation in murine models. However, research on capsular polysaccharides from B. uniformis, a Bacteroides species with reduced abundance in colons of patients with ulcerative colitis, remains scarce. In this study, we extracted a neutral polysaccharide component from B. uniformis ATCC8492, termed BUCPS1B, using ultrasonic disruption, ethanol precipitation, and anion exchange chromatography. Structural characterization revealed BUCPS1B as a water-soluble polysaccharide with an α-1,4-glucan main chain adorned with minor substituent sugar residues. BUCPS1B alleviated intestinal inflammation in a mouse model of colitis and induced polarization of macrophages into M2-type. Furthermore, BUCPS1B modulated the gut microbiota composition, increased the abundance of the probiotic Akkermansia muciniphila and altered the gut metabolic profile to promote phenylalanine and short chain fatty acids metabolism. BUCPS1B is therefore a promising candidate to prevent inflammation and augment intestinal health.

Targeting Molecular Signaling Pathways and Cytokine Responses to Modulate c-MYC in Acute Myeloid Leukemia

Overexpression of the MYC oncogene, encoding c-MYC protein, contributes to the pathogenesis and drug resistance of acute myeloid leukemia (AML) and many other hematopoietic malignancies. Although standard chemotherapy has predominated in AML therapy over the past five decades, the clinical outcomes and patient response to treatment remain suboptimal. Deeper insight into the molecular basis of this disease should facilitate the development of novel therapeutics targeting specific molecules and pathways that are dysregulated in AML, including fms-like tyrosine kinase 3 (FLT3) gene mutation and cluster of differentiation 33 (CD33) protein expression. Elevated expression of c-MYC is one of the molecular features of AML that determines the clinical prognosis in patients. Increased expression of c-MYC is also one of the cytogenetic characteristics of drug resistance in AML. However, direct targeting of c-MYC has been challenging due to its lack of binding sites for small molecules. In this review, we focused on the mechanisms involving the bromodomain and extra-terminal (BET) and cyclin-dependent kinase 9 (CDK9) proteins, phosphoinositide-Akt-mammalian target of rapamycin (PI3K/AKT/mTOR) and Janus kinase-signal transduction and activation of transcription (JAK/STAT) pathways, as well as various inflammatory cytokines, as an indirect means of regulating MYC overexpression in AML. Furthermore, we highlight Food and Drug Administration (FDA)-approved drugs for AML, and the results of preclinical and clinical studies on novel agents that have been or are currently being tested for efficacy and tolerability in AML therapy. Overall, this review summarizes our current knowledge of the molecular processes that promote leukemogenesis, as well as the various agents that intervene in specific pathways and directly or indirectly modulate c-MYC to disrupt AML pathogenesis and drug resistance.

Surgical stress induced tumor immune suppressive environment

Despite significant advances in cancer treatment over the decades, surgical resection remains a prominent management approach for solid neoplasms. Unfortunately, accumulating evidence suggests that surgical stress caused by tumor resection may potentially trigger postoperative metastatic niche formation. Surgical stress not only activates the sympathetic-adrenomedullary axis and hypothalamic-pituitary-adrenocortical axis but also induces hypoxia and hypercoagulable state. These adverse factors can negatively impact the immune system by downregulating immune effector cells and upregulating immune suppressor cells, which contribute to the colonization and progression of postoperative tumor metastatic niche. This review summarizes the effects of surgical stress on four types of immune effector cells (neutrophils, macrophages, natural killer cells and cytotoxic T lymphocytes) and two types of immunosuppressive cells (regulatory T cells and myeloid-derived suppressor cells), and discusses the immune mechanisms of postoperative tumor relapse and progression. Additionally, relevant therapeutic strategies to minimize the pro-tumorigenic effects of surgical stress are elucidated.

Role of Tumor-Associated Macrophages in Cervical Cancer: Integrating Classical Perspectives with Recent Technological Advances

Tumor-associated macrophages (TAMs) play a pivotal role in the tumor microenvironment, influencing cancer progression and contributing to poor prognosis. However, in cervical cancer (CC), their significance and involvement are relatively less studied than in other gynecological cancers such as ovarian and endometrial cancer. This review aims to provide an overview of TAMs, covering their origins and phenotypes and their impact on CC progression, along with major TAM-targeted therapeutic approaches. Furthermore, we advocate for the integration of cutting-edge research methodologies, such as single-cell RNA sequencing and spatial RNA sequencing, to enable in-depth and comprehensive investigations into TAMs in CC, which would be beneficial in leading to more personalized and effective immunotherapy strategies for patients with CC.

ZMIZ1 Upregulation of TET3-Mediated Hydroxymethylation Induces M2 Polarization of Kupffer Cells in Hepatocellular Carcinogenesis by Mediating Notch1/c-Myc Signaling

Hydroxymethylation of DNA, mediated by the ten-eleven translocation (TET) family of methylcytosine dioxygenases, represents a crucial epigenetic modification that manipulates gene expression in numerous biological processes. This study focuses on the effect of TET3 on the polarization of Kupffer cells (KCs) and its connection to the development of hepatocellular carcinoma (HCC). TET3 was found to be abundant in KCs, and its knockdown induced an M2-M1 phenotype shift, resulting in the suppression of viability, migration, and invasion of cocultured HCC cells. Additionally, the TET3 knockdown inhibited the tumorigenesis of HCC cells in nude mice. Downstream targets of TET3 were predicted using bioinformatics. TET3-mediated DNA hydroxymethylation of zinc finger MIZ-type containing 1 (ZMIZ1) promoter. The ZMIZ1 protein interacted with notch receptor 1 (Notch1) protein to activate the transcription of c-Myc. Silencing of ZMIZ1 in KCs similarly suppressed M2 polarization of KCs and malignant phenotype of cocultured HCC cells. However, these changes were counteracted by the overexpression of either Notch1 or c-Myc overexpression in KCs. In summary, this study demonstrates that TET3-mediated hydroxymethylation of ZMIZ1 enhances hepatocellular carcinogenesis by promoting M2 skewing of KCs through the Notch1/c-Myc axis.

The role of NFATc1 in the progression and metastasis of prostate cancer: A review on the molecular mechanisms and signaling pathways

A common type of cancer among men is the prostate cancer that kills many people every year. The multistage of this disease and the involvement of the vital organs of the body have reduced the life span and quality of life of the people involved and turned the treatment process into a complex one. NFATc1 biomarker contributes significantly in the diagnosis and treatment of this disease by increasing its expression in prostate cancer and helping the proliferation, differentiation, and invasion of cancer cells through different signaling pathways. NFATc1 is also able to target the metabolism of cancer cells by inserting specific oncogene molecules such as c-myc that it causes cell growth and proliferation. Bone is a common tissue where prostate cancer cells metastasize. In this regard, the activity of NFATc1, through the regulation of different signaling cascades, including the RANKL/RANK signaling pathway, in turn, increases the activity of osteoclasts, and as a result, bone tissue is gradually ruined. Using Silibinin as a medicinal plant extract can inhibit the activity of osteoclasts related to prostate cancer by targeting NFATc. Undoubtedly, NFATc1 is one of the effective oncogenes related to prostate cancer, which has the potential to put this cancer on the path of progression and metastasis. In this review, we will highlight the role of NFATc1 in the progression and metastasis of prostate cancer. Furthermore, we will summarize signaling pathways and molecular mechanism, through which NFATc1 regulates the process of prostate cancer.

Circular RNA P4HB promotes glycolysis and tumor progression by binding with PKM2 in lung adenocarcinoma

BACKGROUND

Emerging evidence indicates that circular RNAs (circRNAs) play vital roles in tumor progression, including lung adenocarcinomas (LUAD). However, the mechanisms by which circRNAs promote the progression of LUAD still require further investigation.

METHODS

Quantitative real-time PCR was performed to detect the expression of circP4HB in LUAD tissues and cells. Then, Kaplan-Meier analysis was used to determine the prognostic value of circP4HB expression. We employed RNA pull-down, RNA immunoprecipitation, mass spectrometry, cells fraction, glucose consumption, lactate production, pyruvate kinase M2 (PKM2) activity, and macrophage polarization assays to uncover the underlying mechanisms of circP4HB in LUAD.

RESULTS

We found that circP4HB is upregulated in LUAD tissues and correlated with advanced TNM stages and lymph node metastasis. LUAD patients with high circP4HB expression had poor prognoses. Functionally, circP4HB promoted LUAD progression in vivo and in vitro. Upregulated circP4HB increased glucose consumption, lactate production and accelerated aerobic glycolysis in LUAD cells. Mechanically, circP4HB mainly accumulated in the cytoplasm of LUAD cells and bound with PKM2 and subsequently upregulating PKM2 enzymatic activity by increasing its tetramer formation. Additionally, circP4HB promoted M2 macrophage phenotype shift via targeting PKM2. Finally, rescue assays further confirmed that circP4HB could promote LUAD cell progression through its interaction with PKM2.

CONCLUSION

These results demonstrate that circP4HB could promote LUAD progression, indicating circP4HB might be a potential therapeutic target of LUAD.

Role of the tumor microenvironment in the lymphatic metastasis of cervical cancer (Review)

Lymphatic metastasis is the primary type of cervical cancer metastasis and is associated with an extremely poor prognosis in patients. The tumor microenvironment primarily includes cancer-associated fibroblasts, tumor-associated macrophages, myeloid-derived suppressor cells, immune and inflammatory cells, and blood and lymphatic vascular networks, which can promote the establishment of lymphatic metastatic sites within immunosuppressive microenvironments or promote lymphatic metastasis by stimulating lymphangiogenesis and epithelial-mesenchymal transformation. As the most important feature of the tumor microenvironment, hypoxia plays an essential role in lymph node metastasis. In this review, the known mechanisms of hypoxia, and the involvement of stromal components and immune inflammatory cells in the tumor microenvironment of lymphatic metastasis of cervical cancer are discussed. Additionally, a summary of the clinical trials targeting the tumor microenvironment for the treatment of cervical cancer is provided, emphasizing the potential and challenges of immunotherapy.

Marsdenia tenacissima enhances immune response of tumor infiltrating T lymphocytes to colorectal cancer

INTRODUCTION

Tumor-infiltrating T lymphocytes in the tumor microenvironment are critical factors influencing the prognosis and chemotherapy outcomes. As a Chinese herbal medicine, Marsdenia tenacissima extract (MTE) has been widely used to treat cancer in China. Its immunoregulatory effects on tumor-associated macrophages is well known, but whether it regulates tumor-infiltrating T-cell functions remains unclear.

METHOD

We collected 17 tumor samples from MTE-administered colorectal cancer patients, 13 of which showed upregulation of CD3+/CD8+ tumor-infiltrating T cells. Further in vitro and in vivo experiments were performed to investigate the regulatory effects of MTE on tumor-infiltrating T cells and immune escape of tumors.

RESULTS

Under single and co-culture conditions, MTE inhibited TGF-β1 and PD-L1 expression in the colorectal cancer (CRC) cell lines HCT116 and LoVo. In Jurkat cells, MTE inhibited FOXP3 and IL-10 expression, increased IL-2 expression, but had no effect on PD-1 expression. These findings were confirmed in vitro using subcutaneous and colitis-associated CRC mouse models. MTE also increased the density of CD3+/CD8+ tumor-infiltrating T cells and exhibited considerable tumor-suppressive effects in these two tumor mouse models.

CONCLUSIONS

Our findings suggested that MTE inhibits the immune escape of cancer cells, a precipitating factor increasing the immune response of T lymphocytes.

Rhein-attenuates LPS-induced acute lung injury via targeting NFATc1/Trem2 axis

BACKGROUND

Evidence indicated that the early stage transition of macrophages' polarization stages yielded a superior prognosis for acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). Rhein (cassic acid) is one major component of many traditional Chinese medicines, and has been reported to perform with strong anti-inflammation capabilities. However, the role rhein played and the mechanism via which it did so in LPS-induced ALI/ARDS remain unclear.

METHODS

ALI/ARDS was induced by LPS (3 mg/kg, i.n, st), accompanied by the applications of rhein (50 and 100 mg/kg, i.p, qd), and a vehicle or NFATc1 inhibitor (10 mg/kg, i.p, qd) in vivo. Mice were sacrificed 48 h after modeling. Lung injury parameters, epithelial cell apoptosis, macrophage polarization, and oxidative stress were examined. In vitro, conditioned medium from alveolar epithelial cells stimulated by LPS was used for culturing a RAW264.7 cell line, along with rhein administrations (5 and 25 μM). RNA sequencing, molecule docking, biotin pull-down, ChIP-qPCR, and dual luciferase assay were performed to clarify the mechanisms of rhein in this pathological process.

RESULTS

Rhein significantly attenuated tissue inflammation and promoted macrophage M2 polarization transition in LPS-induced ALI/ARDS. In vitro, rhein alleviated the intracellular ROS level, the activation of P65, and thus the M1 polarization of macrophages. In terms of mechanism, rhein played its protective roles via targeting the NFATc1/Trem2 axis, whose function was significantly mitigated in both Trem2 and NFATc1 blocking experiments.

CONCLUSION

Rhein promoted macrophage M2 polarization transition by targeting the NFATc1/Trem2 axis to regulate inflammation response and prognosis after ALI/ARDS, which shed more light on possibilities for the clinical treatments of this pathological process.

Tumor microenvironment promotes lymphatic metastasis of cervical cancer: its mechanisms and clinical implications

Although previous studies have shed light on the etiology of cervical cancer, metastasis of advanced cervical cancer remains the main reason for the poor outcome and high cancer-related mortality rate. Cervical cancer cells closely communicate with immune cells recruited to the tumor microenvironment (TME), such as lymphocytes, tumor-associated macrophages, and myeloid-derived suppressor cells. The crosstalk between tumors and immune cells has been clearly shown to foster metastatic dissemination. Therefore, unraveling the mechanisms of tumor metastasis is crucial to develop more effective therapies. In this review, we interpret several characteristics of the TME that promote the lymphatic metastasis of cervical cancer, such as immune suppression and premetastatic niche formation. Furthermore, we summarize the complex interactions between tumor cells and immune cells within the TME, as well as potential therapeutic strategies to target the TME.

A Comprehensive View of the Cancer-Immunity Cycle (CIC) in HPV-Mediated Cervical Cancer and Prospects for Emerging Therapeutic Opportunities

Cervical cancer (CC) is the fourth most common cancer in women worldwide, with more than 500,000 new cases each year and a mortality rate of around 55%. Over 80% of these deaths occur in developing countries. The most important risk factor for CC is persistent infection by a sexually transmitted virus, the human papillomavirus (HPV). Conventional treatments to eradicate this type of cancer are accompanied by high rates of resistance and a large number of side effects. Hence, it is crucial to devise novel effective therapeutic strategies. In recent years, an increasing number of studies have aimed to develop immunotherapeutic methods for treating cancer. However, these strategies have not proven to be effective enough to combat CC. This means there is a need to investigate immune molecular targets. An adaptive immune response against cancer has been described in seven key stages or steps defined as the cancer-immunity cycle (CIC). The CIC begins with the release of antigens by tumor cells and ends with their destruction by cytotoxic T-cells. In this paper, we discuss several molecular alterations found in each stage of the CIC of CC. In addition, we analyze the evidence discovered, the molecular mechanisms and their relationship with variables such as histological subtype and HPV infection, as well as their potential impact for adopting novel immunotherapeutic approaches.

Tumor associated macrophage in HPV+ tumors: Between immunosuppression and inflammation

Over the past few decades, with the rise of immunotherapies, tumor infiltrating immune cells were increasingly investigated. Indeed, they may represent biomarkers for patient outcome prediction, they may bear immune checkpoint markers that can be targeted by therapeutic antibodies and mechanistic studies may reveal how to tweak their activation profile so that we can re-direct them towards tumor cells. Macrophages possess a central place in tissue homeostasis for tissue remodeling and cleaning, transformed cell elimination, phagocytosis and regulation of inflammation via cytokine production. All these functions allow the discovery of approaches to target Tumor Associated Macrophages (TAMs) using immunotherapies. Indeed, TAMs express known immune checkpoint markers such as PD-L1, CD40, Sirp-α and markers such as CD163, CD204, TREM2, TREM1 associated with prognosis. In the context of therapies TAM may participate to antibody dependent cell phagocytosis (ADCP) thanks to FCγ-Receptors. Here, we will review the recent literature on TAMs in the specific context of HPV⁺ tumors. Indeed, HPV infection of mucosal tissue may lead to head and neck, cervical, penile, anal and vaginal cancers. HPV⁺ tumors exhibit a higher immune cell infiltrate, which relies on inflammation, immunosuppression and anti-viral response. In this context, and considering the many functions on macrophages, we will show the versatility of TAMs in a tumor microenvironment with viral infection features.

A panel of seven immune-related genes can serve as a good predictive biomarker for cervical squamous cell carcinoma

Objective: Cervical cancer is one of the most common gynecological malignancies. The interaction between tumor microenvironment and immune infiltration is closely related to the progression of cervical squamous cell carcinoma (CSCC) and patients' prognosis. Herein, a panel of immune-related genes was established for more accurate prognostic prediction. Methods: The transcriptome information of tumor and normal samples were obtained from TCGA-CSCC and GTEx. Differentially expressed genes (DEGs) were defined from it. Immune-related genes (IRGs) were retrieved from the ImmPort database. After removing the transcriptome data which not mentioned in GSE44001, IR-DEGs were preliminarily identified. Then, TCGA-CSCC samples were divided into training and testing set (3:1) randomly. Univariate Cox analysis, LASSO regression analysis and multivariate Cox analysis were used in turn to construct the signature to predict the overall survival (OS) and disease-free survival (DFS). External validation was performed in GSE44001, and initial clinical validation was performed by qRT-PCR. Function enrichment analysis, immune infiltration analysis and establishment of nomogram were conducted as well. Results: A prognostic prediction signature consisting of seven IR-DEGs was established. High expression of NRP1, IGF2R, SERPINA3, TNF and low expression of ICOS, DES, HCK suggested that CSCC patients had shorter OS (POS<0.001) and DFS (PDFS<0.001). AUC values of 1-, 3-, five- year OS were 0.800, 0.831 and 0.809. Analyses in other validation sets showed good consistency with the results in training set. The signature can serve as an independent prognostic factor for OS (HR = 1.166, p < 0.001). AUC values of 1-, 3-, five- year OS based on the nomogram were 0.769, 0.820 and 0.807. Functional enrichment analysis suggested that these IR-DEGs were associated with receptor interaction and immune cell activity. Immune infiltration analysis indicated that patients in high-risk group had lower immune infiltration, weaker immune function, and were more likely to benefit from immune checkpoint inhibitor therapy. Through qRT-PCR on clinical samples, expression of NRP1, IGF2R, SERPINA3 and TNF were significantly upregulated in tumor tissue, while ICOS and DES were significantly downregulated. Conclusion: To conclude, the immune-related signature can provide strong support for exploration of immune infiltration, prediction of prognosis and response to immunotherapy through stratify CSCC patients into subgroups.

Total glucosides of paeony inhibit breast cancer growth by inhibiting TAMs infiltration through NF-κB/CCL2 signaling

PURPOSE

The high density of tumor-associated macrophages (TAMs) and inflammatory factors are crucial elements leading to tumor immune tolerance. Previously, we found that total glucosides of paeony (TGP) have strong inhibitory effects on the release of various inflammatory factors; however, it is unclear whether the inhibitory effects can improve the inflammatory microenvironment of tumors. Therefore, in the present study, we investigated the mechanism via which TGP depresses tumor growth and metastasis via modulation of TAM infiltration in breast cancer.

METHODS

We assessed the effects of TGP on various mouse models of tumor. Lung metastasis was detected using hematoxylin and eosin staining. T cell (CD3⁺CD4⁺ and CD3⁺CD8⁺) effector and memory subsets, and TAM (CD45⁺CD11b⁺F4/80⁺) populations in the tumor microenvironment (TME) were examined using flow cytometry. Lipopolysaccharide (LPS)-stimulated macrophage experiments were used to investigate the TGP anti-inflammatory effects in vitro. Furthermore, conditional medium (CM) was added to detect 4T1 breast cancer cell growth using a Real-Time Cell Analyzer (RTCA) xCELLigence system. Inflammatory cytokine and chemokine levels were measured using cytometric bead array (CBA) kits and quantitative polymerase chain reaction (qPCR). NF-κB expression in the nucleus was examined by immunofluorescence and Western blot analysis.

RESULTS

TGP suppressed tumor growth and lung metastasis, decreased CD45⁺CD11b⁺F4/80⁺ (TAMs) population obviously, and increased CD44^LowCD62L^Hi (T memory stem cells) and CD44^HiCD62L^Hi (central memory cells) populations in the tumor-infiltrating CD4⁺ and CD8⁺ T cells. In addition, TGP reduced inflammatory factor levels in tumors, thus inhibiting the infiltration of TAMs to improve the inflammation immunosuppressive microenvironment. In the in vitro experiment, TGP inhibited IL-10 and C-C Motif Chemokine Ligand 2 (CCL2) secretion and mRNA expression in LPS-stimulated macrophages to inhibit 4T1 cell growth and restrain macrophages M2 polarization. In addition, TGP can directly inhibit 4T1 cell proliferation by restraining autocrine CCL2 and IL-10. Further mechanistic studies reavealed that TGP inhibited CCL2 secretion by inhibiting NF-κB accumulation in the nucleus in macrophages.

CONCLUSION

TGP reduced TAM recruitment mainly through the NF-κB/CCL2 signaling pathway, thereby promoting T cell infiltration in the TME. TGP has a unique advantage in balancing the inflammatory response. Furthermore, our results present novel insights on the mechanisms underlying TAM infiltration that were inhibited by TGP, with potential application in development of novel therapies targeting CCL2 pathways.