Progressin Tumor-Associated Macrophages in the Treatment of Pancreatic Cancer / 中国医学科学院学报

Pancreatic cancer is one of the digestive system tumors with a high degree of malignancy,and most of the patients are diagnosed in advanced stages.Because of limited available therapies,the mortality of this disease remains high.Tumor-associated macrophages(TAM),the main immune cells in the tumor microenvironment,are involved in the regulation of the occurrence and development of pancreatic cancer.Specifically,TAM are involved in the proliferation,invasion,immune escape,and chemoresistance of pancreatic cancer cells,demonstrating potential in the targeted therapy of pancreatic cancer.In this paper,we summarize the TAM-based therapies including consuming TAM,reprogramming TAM,dynamic imaging of TAM with nanoprobes,and regulating the phagocytic ability of TAM for pancreatic cancer,aiming to provide a theoretical basis for developing new therapies for pancreatic cancer.

The effect of tumor-associated macrophage on proliferation of renal carcinoma cells and related mechanism / 中华泌尿外科杂志

Objective:To investigate the effect of tumor-associated macrophage(TAM) on proliferation of renal carcinoma cells and its related mechanism.Methods:The model of TAM was established by stimulating human monocytic leukemia cell line THP-1 with phorbol myristate acetate (PMA), bacterial endotoxin (LPS) and interferon-γ (IFN- γ). Then the TAM model was co-cultured with carcinoma cell lines ACHN and 786-O in vitro .The cytokines IL-6, TNF-α and IL-1β in TAM supernatant were detected by enzyme-linked immunosorbent assay (ELISA). MTT method was used to detect the proliferation of ACHN and 786-O cells treated with supernatant of TAM or TAM/Tocilizumab. Western blot was used to detect lactate dehydrogenase A (LDHA) expression of both renal cancer cells co-cultured with TAM or TAM/Tocilizumab. The ACHN and 786-O cells with LDHA-overexpression and LDHA-knockdown were cultured in TAM supernatant in vitro. The cell proliferation was detected by MTT and the relative proliferation rate was calculated.Results:THP-1 cells was differentiated into TAM through the treatment of 80 ng/ml PMA combined with 20 ng/ml LPS and 20 ng/ml IFN- γ.The expression rate of CD68, a cell surface marker on TAM, was (36.2 ±4.5)%. When TAM was co-cultured with ACHN cells, the results of ELISA showed that the secretion of IL-6 in the supernatant was significantly elevated compared with that in the supernatant when ACHN cells cultured alone [(138.0 ±12.4) pg/ml and (19.7±4.9) pg/ml], and the secretion of TNF- α [(122.5 ±14.2) pg/ml and (12.6 ±2.3) pg/ml] and IL-1 β [(89.2 ±6.4) pg/ml and (69.2 ±3.5) pg/ml] were also significantly increased. The secretion of IL-6 [(119.2 ±14.8) pg/ml and (17.1 ±3.3) pg/ml], TNF- α [(122.6 ±14.4) pg/ml and (45.7 ±7.2) pg/ml] and IL-1 β [(95.1 ±11.8) pg/ml and (88.2 ±12.7) pg/ml] in the supernatant were also significantly elevated when 786-O cells co-cultured with TAM compared with 786-O cells cultured alone. After treated with the supernatant of TAM for 72 hours, the relative proliferation rates of ACHN and 786-O cells [(128.6 ±21.4)% and (124.2 ±19.7)%] were significantly higher than that of the control group (100.0%). At the same time, the expression of LDHA in ACHN and 786-O cells increased significantly. After 72 hours of treatment with the supernatant of TAM combined with tocilizumab, the relative proliferation rates of ACHN and 786-O cells [(76.5±13.7)% and (74.8±12.5)%] were significantly lower than that of the control group(100.0%), and the expression of LDHA was also significantly decreased at the same time. The relative proliferation rates of ACHN and 786-O cells in LDHA overexpression group [(121.5 ±17.2)% and (122.7±21.6)%]were significantly higher than that in blank-vector-transfection group[(93.3±10.7)% and (89.8±11.2)%], while the relative proliferation rates in LDHA-knockdown group [(61.4±11.2)% and (58.0 ±10.6)% ]were significantly lower than that in blank-vector-transfection group.Conclusions:By secreting IL-6, TAM can up-regulate the expression of LDHA and promote the proliferation of renal cancer cells.

Effect Mechanism of Modified Baitouwengtang Treating Colorectal Cancer by Regulating CSF1R/STING/TBK1 Signaling to Polarize Phenotype of Tumor-associated Macrophages （TAMs） / 中国实验方剂学杂志

ObjectiveThis study aims to investigate the effect of modified Baitouwengtang （MBTWD） on tumor growth and the number of tumor-associated macrophages （TAMs） in tumor tissue of MC38 cell tumor-bearing mice with colorectal cancer and explores whether MBTWD mediates the remodeling of TAM phenotype to play an immunologically antitumor effect. MethodFirstly， The C57BL/6 mouse tumor model grafted subcutaneously was established， and then model mice were classified into a model group， positive control group（3 mg·kg-1）， and MBTWD groups with high and low dosages（23.43、46.86 g·kg-1）， with 10 mice in each group. In addition， 10 healthy mice were set as the blank group， and the changes in body weight， tumor volume， and survival status of mice in each group were observed. Tumor tissue， spleen， and peripheral blood were collected to calculate the tumor volume change， tumor inhibition rate， and spleen mass. Hematoxylin-eosin （HE） staining was used to observe the morphological changes of tumor tissue， and an immunofluorescence assay was used to detect the expression levels of CD4， CD8， and CD206 in tumor tissues of tumor-bearing mice. The secretion levels of transforming growth factor （TGF）-β， interleukin （IL）-6， and chemokine （C-C Motif） ligand 2 （CCL2） in peripheral serum were measured by using enzyme-linked immunosorbent assay （ELISA）. Secondly， a co-culture model induced by IL-4 in vitro of MC38 cells and murine monocytic macrophage RAW264.7 cells was established. Cell proliferation and activity assay （CCK-8） was used to detect the inhibitory effect of MBTWD containing serum on cell proliferation. A transwell experiment was used to detect the effect of IL-4-induced M2 macrophages on the invasion of MC38 cells. Flow cytometry was used to detect the expression of CD86 on the membrane of M2 macrophages induced by IL-4 with MBTWD containing serum. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to detect the effect of MBTWD containing serum on the mRNA expression levels of M1 macrophage-related polarization factors CD86， nitric oxide synthase （iNOS）， and IL-12， as well as M2 macrophage-related polarization factors CD206， CD163， and IL-10 after co-cultivation. Finally， the protein expression levels of colony-stimulating factor 1 receptor （CSF1R）， stimulator of interferon genes （STING）， and TANK binding kinase 1 （TBK1） in tumor tissues of tumor-bearing mice were detected by Western blot. ResultIn vivo experimental results show that compared with the model group， the MBTWD can significantly inhibit the tumor growth of tumor-bearing mice. Immunofluorescence experiments show that the MBTWD can increase the number of CD8+ T cell infiltration in tumor tissue of tumor-bearing mice， reduce the number of CD206+ TAMs infiltration， and down-regulate the secretion levels of cytokines IL-6， TGF-β， and CCL2 in peripheral blood of tumor-bearing mice. The results of in vitro experiments show that the MBTWD containing serum has no obvious inhibitory effect on cell proliferation， but the cell supernatant after co-cultivation with RAW264.7 cells can inhibit the proliferation activity of MC38 cells， and the invasion ability of MC38 cells is enhanced by IL-4-induced M2 macrophages. However， this effect can be inhibited in a concentration-dependent manner by the MBTWD containing serum. At the same time， the results of Real-time PCR show that the MBTWD containing serum can up-regulate the mRNA expression levels of M1 macrophage-related polarization factors CD86， iNOS， and IL-12 and down-regulate those of M2 macrophage-related polarization factors CD206， CD163， and IL-10. Flow cytometry results also confirm that the MBTWD containing serum can increase the number of repolarized CD86+ M1 macrophages， indicating that MBTWD can induce M2 macrophages to repolarized M1 macrophages to play an anti-tumor growth role. Finally， Western blot results show that MBTWD can down-regulate the expression of CSF1R protein and up-regulate that of STING and TBK1 proteins in tumor tissue of tumor-bearing mice. ConclusionMBTWD can down-regulate the infiltration number of CD206+ TAMs and increase the infiltration of CD8+ T cells， thereby playing an immunologically antitumor effect on the growth inhibition of colorectal cancer， which may be related to regulating CSF1R signaling and then activating STING/TBK1 signaling pathway to induce phenotypic remodeling of TAMs.

Shuyuwan Regulates M1/M2 Polarization of Tumor-associated Macrophages to Inhibit Progression of Colorectal Cancer / 中国实验方剂学杂志

ObjectiveTo explore the molecular mechanism of Shuyuwan regulating polarization of tumor-associated macrophages （TAMs） to inhibit the progression of colorectal cancer （CRC）. MethodThe nude mouse model of orthotopic transplantation of colon cancer was established. Male BALB/c-nu nude mice （n=28， 4 weeks old） were randomly assigned into 4 groups （n=7）： Model group （normal saline） and low-， medium-， and high-dose （1.725， 2.310， 2.895 g·kg-1·d-1， respectively） Shuyuwan groups. On day 9 after the tumor block was inoculated， the mice were administrated by gavage with corresponding agents at a dose of 15 mL·kg-1 once a day， 6 days a week， and no agent on the 7th day. After two consecutive weeks of intervention， the nude mice were sacrificed and the tumor samples were collected. A part of the colon tissue and the tumor tissue was used to prepare sections， and hematoxylin-eosin （HE） staining was performed for pathological observation. The expression of inducible nitric oxide synthase （iNOS） and arginase-1 （Arg-1） in the tumor tissue was detected by immunohistochemistry （IHC）. The mRNA levels of interleukin-12 （IL-12）， epidermal growth factor （EGF）， and transforming growth factor-β1 （TGF-β1） in the tumor tissue were determined by Real-time polymerase chain reaction （PCR）. Western blot was employed to determine the protein levels of iNOS， IL-12， EGF， and TGF-β1 in the tumor tissue. ResultCompared with the model group， Shuyuwan inhibited the growth of colon cancer cells in nude mice and caused the tumor cell necrosis in different degrees. The high-dose Shuyuwan group had the strongest inhibitory effect on the growth of tumor cells， which basically lost the normal morphology. Furthermore， Shuyuwan up-regulated the expression of iNOS and IL-12 in M1-type macrophages （P<0.05） and down-regulated the expression of Arg-1， EGF， and TGF-β1 in M2-type macrophages （P<0.05）， which indicated the weakened polarization of macrophages toward M2 type and the enhanced polarization toward M1 type after treatment with Shuyuwan. ConclusionShuyuwan can inhibit the growth of orthotopically transplanted colon tumor by blocking the polarization of TAMs to M2 type and promoting the polarization of TAMs to M1 type.

Research advances in tumor-associated macrophages in hepatocellular carcinoma microenvironment / 临床肝胆病杂志

Since there is a lack of obvious clinical symptoms in the early stage of hepatocellular carcinoma (HCC), most patients have progressed to the advanced stage at the time of confirmed diagnosis. There are limited treatment options for HCC patients who miss the opportunity for surgery, so it is of great importance to find new therapeutic targets. Tumor-associated macrophages (TAMs) are a group of macrophages existing in the tumor immune microenvironment and affect the malignant behaviors of HCC cells and the state of immune escape within the tumor. This article introduces the origin and classification of TAM, summarizes the role and mechanism of TAMs in vascular proliferation, invasion and metastasis, formation and maintenance of stemness, and anti-tumor immunity in HCC, and briefly describes the current research advances in therapeutic targets for TAM, and it is pointed out that targeting TAM may be a promising direction for clinical treatment.

Research Progress on the Role of Tumor-Associated Macrophages in Multiple Myeloma --Review / 中国实验血液学杂志

Bone marrow microenvironment is a highly complex environment surrounding tumor, which plays an important role in the survival, proliferation, drug resistance and migration of multiple myeloma (MM) cells. As an important cellular component in tumor microenvironment, tumor-associated macrophages(TAM) has attracted attention due to its key role in tumor progression and drug resistance. Targeting TAM has shown potential therapeutic value in cancer treatment. In order to clarify the role of macrophages in MM progression, it is necessary to understand the differentiation of TAM and its characteristics of promoting MM. This paper reviews the research progress on how TAM is programmed in MM and the mechanism of TAM promoting tumor development and drug resistance.

Prevention and treatment of lung cancer by regulating tumor-associated macrophages with traditional Chinese medicine / 中国中药杂志

Lung cancer is one of the common malignant tumors in the world, and its incidence and mortality is increasing year by year. Interactions between tumor cells and immune cells in the tumor microenvironment(TME) affect tumor proliferation, infiltration, and metastasis. Tumor-associated macrophages(TAMs) are prominent components of TME, and they have dual regulation effects on malignant progression of lung cancer. The number, activity, and function of M2 macrophages are related to the poor prognosis of lung cancer, and M2 macrophages participate in tumor angiogenesis and immune escape. It has been proved that traditional Chinese medicines(TCMs) and their active ingredients can enhance the antitumor effects, reduce the toxicity of chemotherapy and radiotherapy, and prolong the survival rates of patients with cancer. This paper summarized the role of TAMs in the lung cancer initiation and progression, explored the molecular mechanism of TCM in regulating the recruitment, polarization phenotype, activity, and expression of related factors and proteins of TAMs, and discussed related signal pathways in the prevention and treatment of lung cancer based on the TCM theory of "reinforcing healthy qi and eliminating pathogen". This paper is expected to provide new ideas for the immunotherapy of targeted TAMs.

Experimental study of exosome derived from bone marrow mesenchymal stem cells in treating pancreatic cancer through regulation of tumor-associated macrophages polarization / 中华肝胆外科杂志

Objective:To investigate the therapeutic effect of exosomes divided from bone marrow mesenchymal stem cell (BMSC) on pancreatic cancer in vivo through regulation of tumor-associated macrophages (TAM) polarization.Methods:Ten male C57BL/6 mice weighing approximately 20 g, ages 4 weeks, were used for BMSC exosomes extraction and PKH26 labelling. Thirty female SPF BALB/c-nu/nu nude mice weighing approximately (18.56±0.85) g, ages 4-6 weeks, were adopted for pancreatic carcinoma models. The models were randomly divided into 3 groups with 10 in each: control group (injected with PBS through tail vein), portal vein treatment group (injected with exosomes in PBS through portal vein), tail vein treatment group (injected with exosomes in PBS through tail vein). After the models were executive 8 weeks later, the percentage of PKH26 positive-exosomes in pancreas tissue was quantified by flow cytometry technique. The volume of the primary pancreatic tumor, the tumor volume of inhibitory rate, the number of metastatic nodule, and the ascitic fluid were assess. Also, the weight of liver and the tumor weight were evaluated. The expression of M1 and M2 macrophage-activate biomarkers and the content of pancreatic cancer marker B7-H4 tumor carbohydrate antigen 199 in peripheral blood was detected. Moreover, the expression of Survivin and matrix metalloproteinase-9 (MMP-9) in pancreatic cancer tissue cells was also detected.Results:There was no significant difference for the tumor volume of inhibitory rate between portal vein treatment group (72.4±21.6)% and tail vein treatment group (70.1±20.7)% ( t=0.24, P=0.811). Compared with control group, the volume of the primary pancreatic tumor, the weight of liver, the tumor weight, the number and rate of liver metastatic nodule, the ascitic fluid, and the number of other metastatic nodule were totally lower in the 2 treatment groups with significant difference (all P<0.05). Compared with the control group, iNOS and CD68 in portal vein treatment group and tail vein treatment group were increased, while Arginase, CD206, B7-H4, tumor carbohydrate antigen 199, Survivin and matrix metalloprotein-9 were decreased, with statistically significant differences (all P<0.05). Conclusion:Exosomes derived from BMSC can inhibit the polarization of TAM to the M2 phenotype and induce their polarization to the M1 phenotype, thereby suppressing the proliferation, invasion and migration of pancreatic cancer.

Advances in the Study of Tumor-associated Macrophages in Lung Cancer / 中国肺癌杂志

Lung cancer is one of the malignant tumors with the highest morbidity and mortality in China. Therefore, the research on the treatment of lung cancer is also deepening. At present, there are mainly systemic chemotherapy, targeted therapy for positive driver genes, the application of immune checkpoint inhibitors, anti-tumor angiogenesis therapy and the combination of the different treatment methods mentioned above. The use of these regimens has significantly improved the prognosis of most lung cancer patients, but the prognosis of patients with advanced lung cancer remains unsatisfactory. Recently, more and more attention has been paid to the study of tumor microenvironment (TME). TME consists of immune cells, fibroblasts, vascular endothelial cells and other cellular components as well as related cytokines, which is the basis for the survival and development of tumor cells. As an important immune cell of TME, tumor-associated macrophages (TAMs) refer to macrophages infiltrating in tumor tissues, which can promote tumor cell proliferation, induce tumor immune tolerance, stimulate tumor angiogenesis, and increase the invasion and metastasis ability of tumor cells. Therefore, targeting TAMs has become a hot topic in lung cancer immunotherapy. In this review, the sources, phenotypes, mechanisms of TAMs in lung cancer, as well as future therapeutic targets of TAMs were reviewed to provide reference for optimal treatment of lung cancer.
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The Expression and Clinical Correlation of the CD68 Factor in Acute Myeloid Leukemia Patients / 中国实验血液学杂志

OBJECTIVE@#To analyze the expression and clinical characteristics of CD68 in bone marrow and peripheral blood of patients with acute myeloid leukemia (AML).@*METHODS@#The expression of CD68 in bone marrow blast cells was detected by four-color flow cytometry in 50 newly diagnosed AML patients and 23 controls. The expression of CD68 in peripheral blood of 85 newly diagnosed AML patients, 29 remission AML patients and 24 controls was detected by ELISA. The correlation between the expression rate of non-M3 AML bone marrow CD68, peripheral blood CD68 concentration and white blood cell count and other clinical data was compared respectively.@*RESULTS@#The median CD68 expression rate in myeloid leukemia cells of non-M3 AML patients was 19.7%, significantly higher than control (0.2%) (P<0.001). The median concentration of non-M3 CD68 in peripheral blood was 67.97 pg/ml, significantly higher than in control (29.94 pg/ml)（P<0.01）. There was no statistically significant difference in the plasma CD68 concentration of the peripheral blood between the newly diagnosed (45.72 pg/ml) and the remission stage (55.12 pg/ml) of non-M3 AML patients by paired analysis (P>0.05). The results showed that the higher the expression rate of CD68 in bone marrow, the higher the count of white blood cells in peripheral blood, and the lower the count of hemoglobin and platelet in peripheral blood. The higher the plasma concentration of CD68 in peripheral blood, the higher the white blood cell count and the lower the complete remission rate.@*CONCLUSION@#The expression of CD68 both in bone marrow and peripheral blood of patients with non-M3 AML is higher than that of control group. Patients with high expression of CD68 show a low rate of complete remission, suggesting that the expression level of CD68 is correlated with treatment response.

Long non-coding RNA lnc-SLC2A12-10:1 derived from tumor-associated macrophage exosome aggravates the proliferation and invasion of breast cancer cells through miR-296-5p / 中华内分泌外科杂志

Objective:To investigate the effect of the mechanism of lnc-SLC2A12-10:1 derived from tumor-associated macrophages (TAMs) exosomes on the proliferation and invasion of breast cancer (BC) cells.Methods:GEO microarray analysis was used to screen out the differentially expressed lnc-SLC2A12-10:1 in BC. qRT-PCR was performed to determine the expression level of lnc-SLC2A12-10:1 and miR-296-5p in tissue and cells. Then TAMs and exosomes were isolated. After, interfering the expression level of lnc-SLC2A12-10:1 in exosomes and miR-296-5p expression in cells, then cell proliferation and invasion were detected with the help of MTT and Transwell assays.Results:Compared with adjacent tissues, lnc-SLC2A12-10:1 was significantly up-regulated in BC tissues ( t=7.09, P<0.001) . Compared with normal breast cells, the expression of lnc-SLC2A12-10:1 in T47D and MDA-MB-468 cells was significantly up-regulated ( t=9.90, P<0.001) ( t=12.18, P<0.001) . lnc-SLC2A12-10:1 could act as a ceRNA of miR-296-5p. Knockdown of lnc-SLC2A12-10:1 inhibited BC cell proliferation and invasion, miR-296-5p inhibitor promoted BC cell proliferation and invasion, but this effect could be partially rescued by si--lnc-SLC2A12-10:1-Exo (all P<0.05) . Conclusion:lnc-SLC2A12-10:1 derived from TAMs exosomes promotes BC cell proliferation, invasion and thus advance BC progression.

Engineering a folic acid-decorated ultrasmall gemcitabine nanocarrier for breast cancer therapy: Dual targeting of tumor cells and tumor-associated macrophages

Combination of passive targeting with active targeting is a promising approach to improve the therapeutic efficacy of nanotherapy. However, most reported polymeric systems have sizes above 100 nm, which limits effective extravasation into tumors that are poorly vascularized and have dense stroma. This will, in turn, limit the overall effectiveness of the subsequent uptake by tumor cells via active targeting. In this study, we combined the passive targeting via ultra-small-sized gemcitabine (GEM)-based nanoparticles (NPs) with the active targeting provided by folic acid (FA) conjugation for enhanced dual targeted delivery to tumor cells and tumor-associated macrophages (TAMs). We developed an FA-modified prodrug carrier based on GEM (PGEM) to load doxorubicin (DOX), for co-delivery of GEM and DOX to tumors. The co-delivery system showed small particle size of ∼10 nm in diameter. The ligand-free and FA-targeted micelles showed comparable drug loading efficiency and a sustained DOX release profile. The FA-conjugated micelles effectively increased DOX uptake in cultured KB cancer cells that express a high level of folate receptor (FR), but no obvious increase was observed in 4T1.2 breast cancer cells that have a low-level expression of FR. Interestingly, in vivo, systemic delivery of FA-PGEM/DOX led to enhanced accumulation of the NPs in tumor and drastic reduction of tumor growth in a murine 4T1.2 breast cancer model. Mechanistic study showed that 4T1.2 tumor grown in mice expressed a significantly higher level of FOLR2, which was selectively expressed on TAMs. Thus, targeting of TAM may also contribute to the improved in vivo targeted delivery and therapeutic efficacy.

Research Progress of M2-type Tumor-associated Macrophages in Lung Cancer / 肿瘤防治研究

Tumor-associated macrophages (TAMs) account for a large proportion in tumor stroma, and can be divided into M1 type (anti-tumoral) and M2 type (pro-tumoral). Recently, many experimental and clinical studies have shown that M2-type TAMs are significantly correlated with tumor stage, tumor cell differentiation, depth of invasion, angiogenesis, lymph node metastasis and therapeutic drug resistance, which eventually affects the prognosis of tumor patients. Targeted TAMs therapy is expected to benefit cancer patients. This paper reviews the recent research of M2-type TAMs in lung cancer.

Bushen Jiedu Prescription Inhibits Metastasis of Colorectal Cancer by Regulating Polarization of M2-TAMs in Vivo / 中国实验方剂学杂志

ObjectiveTo explore the inhibitory effect of Bushen Jiedu prescription （BSJDP） on the metastasis of colorectal cancer （CRC） via activation of M2 tumor-associated macrophages （M2-TAMs） in vivo. MethodThe model of xenograft tumor was established with C57BL/6 mice， and then the model mice were randomly assigned into blank control group， Bushen Jiedu recipe-low dose （11.2 g·kg-1） group （BSJDP-L）， and Bushen Jiedu Recipe-high dose （22.4 g·kg-1） group （BSJDP-H）. Tumors were abolished when the volume reached 1.5-2.0 cm3. The mice were sacrificed 28 days post tumor abolishing and then the lung metastasis was observed. Histopathological changes in lung metastasis were examined by hematoxylin-eosin （HE） staining of metastasis tissues， and immunofluorescence （IF） staining was employed to observe the effect of BSJDP on tumor apoptosis and hypoxia. Flow cytometry was performed to analyze the macrophages M1/M2 ratio of tumor tissue. The expression levels of the genes （Arg1， CD206， and CD163） associated with the polarization of M2-TAMs were determined by Real-time fluorescent quantitative polymerase chain reaction （Real-time PCR）. ResultThe metastasis rate was 70%， 40%， and 10% in the blank control group， BSJDP-L group， and BSJDP-H group， respectively. The lower metastasis rates of BSJDP-L and BSJDP-H groups proved that BSJDP significantly inhibited lung metastasis of CRC. Compared with the blank control group， BSJDP-L and BSJDP-H reduced the tumor cell infiltration in tumor tissue （P<0.01）， increased the apoptosis of tumor cells， alleviated the hypoxic environment， and down-regulated the expression of Arg1， CD206， and CD163 in the tumor tissue （P<0.01）. In addition， the ratio of M2 macrophages ranked in a descending order of blank control group （34.867%） > BSJDP-L group （22.033%） > BSJDP-H group （11.633%） （P<0.01）. ConclusionBSJDP inhibits the lung metastasis of CRC by inhibiting the activation of M2-TAMs in the tumor microenvironment.

Gold nanoparticle-directed autophagy intervention for antitumor immunotherapy via inhibiting tumor-associated macrophage M2 polarization

Tumor-associated macrophages (TAMs), one of the dominating constituents of tumor microenvironment, are important contributors to cancer progression and treatment resistance. Therefore, regulation of TAMs polarization from M2 phenotype towards M1 phenotype has emerged as a new strategy for tumor immunotherapy. Herein, we successfully initiated antitumor immunotherapy by inhibiting TAMs M2 polarization via autophagy intervention with polyethylene glycol-conjugated gold nanoparticles (PEG-AuNPs). PEG-AuNPs suppressed TAMs M2 polarization in both in vitro and in vivo models, elicited antitumor immunotherapy and inhibited subcutaneous tumor growth in mice. As demonstrated by the mRFP-GFP-LC3 assay and analyzing the autophagy-related proteins (LC3, beclin1 and P62), PEG-AuNPs induced autophagic flux inhibition in TAMs, which is attributed to the PEG-AuNPs induced lysosome alkalization and membrane permeabilization. Besides, TAMs were prone to polarize towards M2 phenotype following autophagy activation, whereas inhibition of autophagic flux could reduce the M2 polarization of TAMs. Our results revealed a mechanism underlying PEG-AuNPs induced antitumor immunotherapy, where PEG-AuNPs reduce TAMs M2 polarization via induction of lysosome dysfunction and autophagic flux inhibition. This study elucidated the biological effects of nanomaterials on TAMs polarization and provided insight into harnessing the intrinsic immunomodulation capacity of nanomaterials for effective cancer treatment.

Interference of P2X4 receptor expression in tumor-associated macrophages suppresses migration and invasion of glioma cells / 南方医科大学学报

OBJECTIVE@#To investigate the effect of interference of P2X4 receptor expression in tumor-associated macrophages (TAMs) on invasion and migration of glioma cells.@*METHODS@#C57BL/6 mouse models bearing gliomas in the caudate nucleus were examined for glioma pathology with HE staining and expressions of Iba-1 and P2X4 receptor with immunofluorescence assay. RAW264.7 cells were induced into TAMs using conditioned medium from GL261 cells, and the changes in mRNA expressions of macrophage polarization-related markers and the mRNA and protein expressions of P2X4 receptor were detected with RT-qPCR and Western blotting. The effect of siRNA-mediated P2X4 interference on IL-1β and IL-18 mRNA and protein expressions in the TAMs was detected with RT-qPCR and Western blotting. GL261 cells were cultured in the conditioned medium from the transfected TAMs, and the invasion and migration abilities of the cells were assessed with Transwell invasion and migration experiment.@*RESULTS@#The glioma tissues from the tumor-bearing mice showed a significantly greater number of Iba-1-positive cells, where an obviously increased P2X4 receptor expression was detected (P=0.001), than the brain tissues of the control mice (P < 0.001). The M2 macrophage markers (Arg-1 and IL-10) and M1 macrophage markers (iNOS and TNF-α) were both significantly up-regulated in the TAMs derived from RAW264.7 cells (all P < 0.01), but the up-regulation of the M2 macrophage markers was more prominent; the expression levels of P2X4 receptor protein and mRNA were both increased in the TAMs (P < 0.05). Interference of P2X4 receptor expression significantly lowered the mRNA(P < 0.01)and protein (P < 0.01, P < 0.05)expression levels of IL-1β and IL-18 in the TAMs and obviously inhibited the ability of the TAMs to promote invasion and migration of the glioma cells (P < 0.05).@*CONCLUSION@#Interference of P2X4 receptor in the TAMs suppresses the migration and invasion of glioma cells possibly by lowering the expressions of IL-1β and IL-18.

Evaluation of the immunomodulatory activity of thalidomide on tumor-associated macrophages in the 4T1 murine metastatic breast cancer model / [Avaliação do efeito imunomodulador da talidomida em macrófagos associados a tumores no modelo murino de câncer de mama metastático 4T1]

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

No presente trabalho, foi avaliado o efeito imunomodulador de diferentes doses de talidomida em macrófagos associados ao tumor (TAMs), em um modelo murino de câncer de mama. Camundongos foram inoculados com células 4T1, na região do flanco esquerdo, e tratados com talidomida, uma vez ao dia, nas doses de 50, 100 e 150mg/k, por massa corporal, do quinto dia ao 28º dia de inoculação tumoral. Os tumores foram medidos, o índice de proliferação celular e a contagem de TAMs foram avaliados nos tumores primários e nos pulmões com metástases. Além disso, a taxa de metástases pulmonares também foi avaliada. A talidomida na dose de 150mg/kg diminuiu significativamente o crescimento tumoral, o índice de proliferação celular e a infiltração de TAMs nos tumores primários. Por outro lado, maior número de TAMs e menor índice de proliferação celular foram observados nos pulmões metastáticos, em camundongos tratados com 150mg/kg de talidomida. Ademais, a talidomida na dose de 150mg/kg diminuiu significativamente os nódulos metastáticos nos pulmões. Os resultados demonstraram que o tratamento com talidomida diminuiu o crescimento tumoral e as metástases pulmonares em camundongos, associado com diferentes efeitos na infiltração de TAMs nesses locais.(AU)

Regulatory effects of plant polysaccharides on tumor-associated macrophages (TAMs): progress and perspectives / 中华微生物学和免疫学杂志

With the appearance of the disadvantages of traditional tumor treatment, immunotherapy has entered people′s horizons as modern emerging treatment strategies, among which plant polysaccharides have received much more attention due to their antitumor activity and significant immunomodulatory effects. Tumor-associated macrophages (TAMs), as a component of tumor microenvironment, are important factors affecting tumors, and the regulation of TAMs by plant polysaccharides is one of the effective immunotherapy to treat tumor. In this review, we mainly described the regulation of TAMs by plant polysaccharides and the underlying mechanisms, and then gave an outlook on the research interests and the development of plant polysaccharides as immune adjuvants, aiming to provide reference for the study of plant polysaccharides in the immunotherapy for tumors.

Role of Tumor Associated Macrophages in Chemotherapy Resistance and Intervention with Traditional Chinese Medicine： A Review / 中国实验方剂学杂志

The tumor incidence goes up with every passing year. Chemotherapy， as one of the main treatment methods， is faced with a major challenge of drug resistance in clinical practice. Tumor-associated macrophages （TAMs） are the key factors inducing chemotherapy resistance of tumors. TAMs are inflammatory cells with the largest number in the tumor microenvironment， which are widely distributed in such epithelial tissues as large intestine and stomach in the immune environment and closely associated with multiple common cancers like breast cancer and colorectal cancer. TAMs can be divided into two phenotypes， with M2-polarized TAMs into the tumor-promoting phenotype that affects the oncogenesis and progression and promotes drug resistance via immune escape， angiogenesis and other ways. At the same time， the frequently utilized chemotherapeutic agents will increase the recruitment of TAMs and trigger the secretion of cytokines， leading to the excessive polarization of macrophages to M2 type， followed by tumor drug resistance. The molecular mechanism of chemotherapy resistance is complex， which is becoming an urgent problem in the field of chemotherapy. Traditional Chinese medicine （TCM） has exhibited unique advantages in resisting tumor drug resistance. It has been proved efficient and safe in improving tumor microenvironment and regulating TAMs by acting on multiple targets via multiple ways， thus adjusting tumor progression and improving drug resistance. Based on related articles published in recent years， this paper reviewed the drug resistance-promoting effect of TAMs via regulating the immune microenvironment and interacting with tumor stem cells and the driving effect of chemotherapeutic agents on drug resistance to figure out the role of TAMs in chemotherapy resistance. Besides， it summarized the mechanisms of TCM in regulating related cytokines， proteins， activity， and the polarization direction of TAMs to expound the effective components of TCM in the intervention of drug resistance. The aim of this paper was to provide reference for further research on the biological mechanism of chemotherapy resistance and its targeted intervention with TCM.

Antitumor strategies based on targeted modulation of tumor-associated macrophages / 中国药科大学学报

@#Tumor-associated macrophages (TAMs) are the most abundant innate immune cells in tumors, which generally exhibit anti-inflammatory M2 phenotypes, and are the key inducers of tumor development, metastasis and drug resistance, and thus becoming a popular target in the field of antitumor immunotherapy.The study and application of nanocarriers optimize TAMs-targeted antitumor therapy.According to the characteristics and functions of TAMs, modulation strategies based on TAMs are elaborated, including TAMs depletion, inhibition of TAMs recruitment and TAMs repolarization.At the same time, in order to apply the above strategies more efficiently and overcome the general off-target problems in treatment, specific TAMs-targeted therapies based on nanocarriers are reviewed and analyzed, including passive targeting to TAMs, active targeting to macrophages and specifically active targeting to M2-TAMs. Finally, based on the limitations of targeting TAMs alone, new therapeutic strategies of targeting both TAMs and tumor cells via nanocarrier based delivery systems are introduced to provide new ideas for the application of these strategies in the field of tumor immunotherapy and combination therapy with other antitumor strategies.