Astragaloside IV suppresses the migration and EMT progression of cervical cancer cells by inhibiting macrophage M2 polarization through TGFβ/Smad2/3 signaling.

Cervical cancer (CC) is a gynecological malignant tumor worldwide. Astragaloside IV (AS-IV) has been found to exert antitumor effects on CC. In addition, M2-polarized macrophages, known as tumor-associated macrophages (TAMs), play an important role in promoting cancer cell growth and angiogenesis. Thus, we explored the association between the antitumor effect of AS-IV and macrophage polarization in CC. Flow cytometry, ELISA, and RT‒qPCR assays were applied to detect the levels of CD163, IL-10, TGFβ, and CD206 in M2 macrophages with or without AS-IV treatment. In addition, conditioned medium (CM) was collected from these M2 macrophages, and CC cells were then cultured in various CMs. Wound healing and transwell assays were used to assess the migratory ability of CC cells. In this study, we found that AS-IV significantly inhibited M2 polarization of macrophages, as shown by decreased CD163, IL-10, TGFβ, and CD206 expression. In addition, compared with CM from M2 macrophages, CM from AS-IV-treated M2 macrophages notably inhibited angiogenesis, migration, and epithelial-mesenchymal transition (EMT) in CC cells. Furthermore, compared with CM from M2 macrophages, CM from AS-IV-treated M2 macrophages markedly reduced p-Smad2 and p-Smad3 protein expression in CC cells, and these changes were reversed by TGF-β treatment. Collectively, suppression of M2-like polarization of macrophages by AS-IV could prevent the migration and EMT of CC cells by inactivating TGF-β/Smad2/3 signaling. These findings might provide some theoretical support for exploring novel treatments for CC.

Shen L ，Li Y ，Hu G ，Song X ，Wang X ，Li X ，Xu X ... -  《-》

Astragaloside IV inhibits lung cancer progression and metastasis by modulating macrophage polarization through AMPK signaling.

Xu F ，Cui WQ ，Wei Y ，Cui J ，Qiu J ，Hu LL ，Gong WY ，Dong JC ，Liu BJ ... -  《JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH》

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

Nuclear factor of activated T cells 1 (NFATc1) is mainly expressed in tumor microenvironment, especially in macrophages. However, whether NFATc1 is involved in the polarization of tumor associated macrophages (TAMs) and tumor progression in cervical cancer (CC) remains unclear. Immunofluorescence staining was used to detect the expression of CD68 and NFATc1 in CC tissues or adjacent normal tissues of patients. RT-qPCR, flow cytometry, ELISA, and inhibitors treatment were used to observe the effect of NFATc1 on TAMs polarization. Clonal formation, scratch, and transwell assays were used to examine the effects of NFATc1-transfected macrophages or NFATc1-transfected TAM on tumor proliferation, migration, and invasion. Further, a xenograft model was established to confirm the roles of NFATc1+ TAM in CC tumorigenesis. NFATc1+CD68+/CD68+ TAMs ratio was significantly increased in CC tissues compared with the normal tissue, and NFATc1+ TAM showed an M2-like TAM subtype. NFATc1 induced macrophages to secrete IL-10, which further induced M2 polarization of macrophages. Mechanically, the c-myc-PKM2 pathway mediated the expression of IL-10 in NFATc1-induced macrophages. Functionally, NFATc1 induced M2 macrophages promoted the proliferation, migration, and invasion of CC cells, and the knockout of NFATc1 in TAMs significantly inhibited the tumor-promoting function of TAMs. Further, the tumorigenesis test in nude mice confirmed that NFATc1+ TAM promoted the tumorigenicity of CC cells in vivo. In conclusion, NFATc1 mediated IL-10 secretion by regulating the c-myc/PKM2 pathway, thereby inducing M2 polarization of TAMs and promoting the progression of CC.

Tan J ，Yang L ，Zhao H ，Ai Y ，Ren L ，Zhang F ，Dong W ，Shi R ，Sun D ，Feng Y ... -  《-》

Astragaloside IV inhibits the progression of liver cancer by modulating macrophage polarization through the TLR4/NF-κB/STAT3 signaling pathway.

The purpose of the present research was to investigate the effect and mechanism of Astragaloside IV (AS-IV) on liver cancer progression in vivo and in vitro. Since M1 macrophages play an essential role in suppressing tumors, while M2 macrophages can accelerate the incidence and progression of tumors by promoting angiogenesis, increasing tumor cell invasion and inhibiting tumor immune response, the effect and mechanism of AS-IV on macrophage polarization and their role in the development of HCC was explored. The effects of different concentrations of AS-IV (0, 50, 80, 100, 120, and 150 μM) on the capacity of hepatocellular carcinoma (HCC) cells to proliferate, migrate, and invade were detected. THP-1 cells were subjected to incubation in PMA for the purpose of stimulating differentiation into M0 macrophages. These macrophages were treated using LPS, IFN-γ, and PMA to produce M1 macrophages or treated using PMA, IL-13, and IL-4 to produce M2 macrophages. HCC cells and M1 or M2 macrophages were co-cultured for 48 hours, then the cell proliferation and migration were measured. The MTT assay was employed to determine cell viability. The capability of the cells to migrate and invade was investigated utilizing the Transwell assay and the wound healing assay. The expression of the M2 macrophage CD206 in macrophages treated with AS-IV was evaluated by flow cytometry. The expression of p-signal transducer and activator of transcription 3 (STAT3), phosphorylated (p)-NF-κB, and toll-like receptor 4 (TLR4) in macrophages was measured after treatment with AS-IV and M2 induction. To verify the function of the TLR4/NF-κB/STAT3 signaling pathway, TLR4 expression was knocked down in M2 macrophages, then the proliferation and migration and the M2 macrophage markers of HCC cells were measured. The effect of AS-IV on HCC in vivo was confirmed by a subcutaneous tumor mouse model. AS-IV was 2 was administered by gavage (0, 40, 80, and 100 mg/kg) for every 3 days. The tumor volume and weight were recorded. AS-IV suppressed the capacities of HCC cells to proliferate, migrate, and invade in a dose-dependent way. M2 macrophages could promote the proliferative, migratory, and invasive ability of Huh-7 cells, which were suppressed by AS-IV. AS-IV directly attenuated the expression of M2 macrophage markers, indicating that AS-IV can inhibit macrophage M2 polarization. M2 macrophages stimulated the expression of p-STAT3, p-NF-κB, and TLR4, while AS-IV decreased the expression compared to the M2 group, indicating that AS-IV can regulate the TLR4/NF-κB/STAT3 signaling pathway. TLR4 small interfering RNA (siRNA/si) inhibited the proliferation of Huh-7 cells. The tumor volume, as well as weight of mice, was significantly reduced by AS-IV, indicating the antitumor impact of AS-IV in vivo. AS-IV can inhibit the proliferative, invasive, and migratory ability of liver cancer through the suppression of the M2 polarization of macrophages, and the mechanism may involve the TLR4/NF-κB/STAT3 signaling pathway. The present study indicates that AS-IV could be an alternative drug to treat liver cancer, and the polarization of macrophages may be a novel treatment target for HCC.

Min L ，Wang H ，Qi H 《American Journal of Translational Research》

M2-polarized tumor-associated macrophages promoted epithelial-mesenchymal transition in pancreatic cancer cells, partially through TLR4/IL-10 signaling pathway.

Liu CY ，Xu JY ，Shi XY ，Huang W ，Ruan TY ，Xie P ，Ding JL ... -  《-》