23-Hydroxybetulinic acid attenuates 5-fluorouracil resistance of colorectal cancer by modulating M2 macrophage polarization via STAT6 signaling.

Macrophage polarization is closely associated with the inflammatory processes involved in the development and chemoresistance of colorectal cancer (CRC). M2 macrophages, the predominant subtype of tumor-associated macrophages (TAMs) in a wide variety of malignancies, have been demonstrated to promote the resistance of CRC to multiple chemotherapeutic drugs, such as 5-fluorouracil (5-FU). In our study, we investigated the potential of 23-Hydroxybetulinic Acid (23-HBA), a significant active component of Pulsatilla chinensis (P. chinensis), to inhibit the polarization of M2 macrophages induced by IL-4. Our results showed that 23-HBA reduced the expression of M2 specific marker CD206, while downregulating the mRNA levels of M2 related genes (CD206, Arg1, IL-10, and CCL2). Additionally, 23-HBA effectively attenuated the inhibitory effects of the conditioned medium from M2 macrophages on apoptosis in colorectal cancer SW480 cells. Mechanistically, 23-HBA prevented the phosphorylation and nuclear translocation of the STAT6 protein, resulting in the inhibition of IL-10 release in M2 macrophages. Moreover, it interfered with the activation of the IL-10/STAT3/Bcl-2 signaling pathway in SW480 cells, ultimately reducing M2 macrophage-induced resistance to 5-FU. Importantly, depleting STAT6 expression in macrophages abolished the suppressive effect of 23-HBA on M2 macrophage polarization, while also eliminating its ability to decrease M2 macrophage-induced 5-FU resistance in cancer cells. Furthermore, 23-HBA significantly diminished the proportion of M2 macrophages in the tumor tissues of colorectal cancer mice, simultaneously enhancing the anti-cancer efficacy of 5-FU. The findings presented in this study highlight the capacity of 23-HBA to inhibit M2 macrophage polarization, a process that contributes to reduced 5-FU resistance in colorectal cancer.

Anemoside A3 Inhibits Macrophage M2-Like Polarization to Prevent Triple-Negative Breast Cancer Metastasis.

Triple negative breast cancer (TNBC) exhibits the characteristics of strong metastatic ability and a high recurrence rate, and M2-type macrophages play an important role in this process. Previous research data suggested that Anemoside A3 (A3), a monomeric component of Pulsatilla Chinensis, could prevent and treat TNBC by converting M0 macrophages into M1 immunogen phenotypes. This study showed that A3 significantly restrained the lung metastases of 4 T1-Luc cells with bioluminescence imaging in vivo and Hematoxylin and Eosin (H&E) staining. Meanwhile, the percentage of M2-type macrophages (CD206+ labeled cells) in the lung tissues was evidently decreased through immunohistochemical assay. We further proved that A3 markedly prevented M2-type polarization induced by IL-4 in vitro, as illustrated by the down-regulated expression of the cell surface marker CD206 protein by FACS and Arg-1, and of the Fizz1 and Ym1 genes by RT-PCR in M2-type macrophages. Furthermore, the invasion and migration of 4 T1 cells, which was promoted by the conditioned medium from M2-type macrophages, could be suppressed by A3. Luminex assay demonstrated that A3 treatment resulted in a reduction of the levels of CCL2, VEGF, CCL7, and MMP-9 in conditioned medium. Additionally, the expression of phosphorylated-STAT3 protein was inhibited by A3, which resulted in the macrophage M2-type polarization arrest, while no significant difference in JAK2 phosphorylation was detected. SiRNA transfection experiments suggested that STAT3 might be the target of A3 inhibiting M2-type polarization of macrophages. In conclusion, these results indicate that A3 could attenuate the metastasis of TNBC by inhibiting the M2-type polarization of macrophages, which may be related to the STAT3 pathway.

Anemoside A3 activates TLR4-dependent M1-phenotype macrophage polarization to represses breast tumor growth and angiogenesis.

The polarization of macrophages has been previously demonstrated to be closely related to immune and inflammatory processes in the tumorigenesis and progression of breast cancer. In the present study, Anemoside A3 (A3), an active compound from Pulsatilla saponins, was screened out and polarized M0 macrophages into the classically activated macrophages (M1-phenotype). We found that A3 is an activator of TLR4/NF-κB/MAPK signaling pathway. A3 increased the expression of CD86+ (a marker of M1 macrophage) in M0 macrophage, and increased the typical M1 macrophage pro-inflammatory cytokines TNF-α, and IL-12 expression in a TLR4-dependent manner. A macrophage-cancer cell co-culture system was established to evaluate whether A3 can could switch tumor-associated macrophages (TAMs) to the M1-phenotype. In the co-culture system, A3 increased the expression of IL-12 in macrophages, whereby suppressing MCF-7 breast cancer cell line proliferation and VEGF-mediated angiogenesis. Moreover, A3 induced M1 macrophage polarization in the 4 T1 murine breast cancer model and effectively inhibited tumor growth and tumor angiogenesis. Collectively, these findings indicated that A3 induced M1 macrophages polarization to repress breast tumorigenesis via targeting the TLR4/NF-κB/MAPK signaling pathway. This study provides a rationale for utilizing traditional Chinese medicine extracts in the immunotherapy of breast cancer.

Self-Control and Problematic Internet Use in College Students: The Chain Mediating Effect of Rejection Sensitivity and Loneliness.

PURPOSE: To explore the relationship between self-control, rejection sensitivity, loneliness, and problematic internet use in college students. PATIENTS AND METHODS: A total of 725 college students were investigated using Self-control Scale, Rejection Sensitivity Questionnaire, Loneliness Scale, and Internet Addiction Scale. RESULTS: ① Correlation analysis showed that self-control was negatively related to rejection sensitivity, loneliness, and problematic internet use; rejection sensitivity was positively related to loneliness and problematic internet use; loneliness was positively related to problematic internet use. ② Chain mediating effect analysis showed that self-control can not only affect problematic internet use in college students, but also through three indirect paths, as follows: the mediating role of rejection sensitivity and loneliness, the chain mediating roles of rejection sensitivity and loneliness, and the mediating effect size, accounting for 9.76%, 20.73%, and 4.88% of the total effect, respectively. CONCLUSION: Rejection sensitivity and loneliness played a chain mediating role in the relationship between self-control and problematic internet use in college students.