A review on the relationship of mast cells and macrophages in breast cancer - Can herbs or natural products facilitate their anti-tumor effects?

Garcinone E suppresses breast cancer growth and metastasis by modulating tumor-associated macrophages polarization via STAT6 signaling

Cancer metastasis remains the most common cause of death in breast cancer patients. Tumor-associated macrophages (TAMs) are a novel therapeutic target for the treatment of metastatic breast cancer. Despite the good anti-cancer activity of garcinone E (GE), there are no reports on its therapeutic effects on breast cancer metastasis. The objective of this study was to examine the anti-cancer effects of GE on metastatic breast cancer. RAW 264.7 and THP-1 cells were polarized to M2 macrophages by IL-4/IL-13 in vitro. A 4T1 mouse breast cancer model and the tail vein breast cancer metastasis model were used to explore the effect of GE on breast cancer growth and metastasis in vivo. In vitro studies showed that GE dose-dependently suppressed IL-4 + IL-13-induced expression of CD206 in both RAW 264.7 cells and differentiated THP-1 macrophages. However, GE did not affect the LPS + IFN-γ-induced polarization to the M1-like macrophages in vitro. GE inhibited the expression of the M2 macrophage specific genes in RAW 264.7 cells, and simultaneously impaired M2 macrophage-induced breast cancer cell proliferation and migration, and angiogenesis. In animal studies, GE significantly suppressed tumor growth, angiogenesis, and lung metastasis in 4T1 tumor-bearing mice, without causing toxicity. In both tumor and lung tissues, the proportion of M2-like TAMs was significantly decreased while the proportion of M1-like TAMs was markedly increased by GE treatment. Mechanistically, GE inhibited phosphorylation of STAT6 in vitro and in vivo. Our results demonstrate for the first time that GE suppresses breast cancer growth and pulmonary metastasis by modulating M2-like macrophage polarization through the STAT6 signaling pathway.

Morphofunctional Parameters of Mast Cell Population in Experimentally Induced Breast Cancer in Rats

Structural and functional parameters of mast cells (MC) in rat mammary glands during experimentally provoked breast cancer were studied by the cytogram, index of cell saturation with secretory products, and degranulation index. The cytogram was calculated in histological sections stained with toluidine blue. The functional conditions of MC were determined by electron microscopy. The study revealed expansion of MC population and activation of their functional state evidenced by significant prevalence of cells with high degranulation degree and reduced saturation index. At the ultrastructural level, MC were characterized by deformation, polymorphism, paleness of secretory granules, and elevation of the number of lacunae in the cytoplasm. The study showed that MC are active players in tumor microenvironment. Remembering heteromorphism of MC, further study of their role in pathogenesis of various tumor diseases seems promising.

dl-THP recovered the decreased NKp44 expression level on CD56dim CD16+ natural killer cells partially in choriocarcinoma microenvironment

Natural killer cell-based immunotherapy has become a leading-edge tool against cancer, but still faces a variety of challenges, such as phenotype shift and dysfunction of NK cells in tumor microenvironment. Thus, finding potent agents that could inhibit the phenotype shift and incapacity of NK cells in the tumor microenvironment is essential for improving antitumor effects. dl-tetrahydropalmatine (dl-THP), one of the active alkaloids of Chinese herb Corydalis Rhizoma, has been proven to possess antitumor activity. However, whether dl-THP acts on NK cells to enhance antitumor activity remains unknown. In this study, we found that the proportion of blood CD56^dimCD16⁺ NK cells was decreased while the proportion of CD56^brightCD16^- NK cells was increased when the cells were cultured in conditional medium (CM, medium from the human choriocarcinoma cell lines JEG-3). dl-THP could alter the varied proportion of CD56^dimCD16⁺ NK cells and CD56^brightCD16^- NK cells in CM respectively. Importantly, the expression level of NKp44 on CD56^dimCD16⁺ NK cells was dramatically reduced when the cells were cultured in CM, which could also be reversed by dl-THP. Furthermore, dl-THP increased the decreased NK-cell cytotoxicity when cells were cultured in CM. In summary, our study demonstrated that dl-THP could recover the decreased NKp44 expression level on CD56^dimCD16⁺ NK cells and restore the cytotoxicity of NK cells in tumor microenvironment.

Ultrasound-Assisted Extraction of Anthocyanins from Malus ‘Royalty’ Fruits: Optimization, Separation, and Antitumor Activity

Red Malus ‘Royalty’ fruits are rich in anthocyanins. This study aimed to obtain the optimal parameters for the extraction and separation of anthocyanins from Malus ‘Royalty’ fruits and to evaluate the inhibitory effect of the enriched anthocyanin fraction on gastric cancer cells. Ultrasonic-assisted extraction was used for the extraction of the anthocyanins of Malus ‘Royalty’ fruit, and the extraction results showed that the optimum parameters were an extraction temperature of 20 °C, a solid–liquid ratio of 1:6 (g/mL), ethanol and formic acid contents of 70% and 0.4%, respectively, an extraction time of 40 min, and an ultrasonic power of 300 W. The optimum extraction parameters to achieve the highest anthocyanin yield by a single-factor experiment coupled with response surface methodology were identified. The separation results showed that the AB-8 macroporous resin was a better purifying material, with 60% ethanol as an adsorbent, and the adsorption–desorption equilibrium times were 6 h and 1 h, respectively. Cyanidin-3-galactoside was the main body composition separation of anthocyanins by a high-performance liquid chromatography-diode array detector. The antitumor activity results showed that the anthocyanins of Malus ‘Royalty’ fruits have a significant inhibitory effect on the gastric cancer cell line BGC-803. The in vitro cell viability test of CCK-8 showed that the inhibitory effect on tumor cells was more significant with the increased anthocyanin concentration, with a half maximal inhibitory concentration (IC₅₀) value of 105.5 μg/mL. The cell morphology was observed by an inverted microscope, and it was found that the backbone of BGC-803 treated with a high concentration of anthocyanins was disintegrated and the nucleoplasm was concentrated. The mechanism of apoptosis was analyzed by Western blotting, and the results showed that with increasing anthocyanin concentration in the medium, the expression levels of the proapoptotic proteins Bax and Bak increased, and the expression levels of the antiapoptotic proteins Bcl-2 and Bcl-xL decreased, which coordinated the regulation of cell apoptosis. This research suggests that the enriched anthocyanin fraction from Malus ‘Royalty’ fruits have potential antitumor and adjuvant therapeutic effects on gastric cancer.

Anti-tumor alkaloids from Peganum harmala

Six alkaloids peharmalines F-K, along with 14 known ones, were isolated from the aerial part of Peganum harmala L.. The structures of the isolated compounds were determined based on their HR-ESI-MS data, extensive NMR spectroscopic analyses, and ECD calculations. 3-(4-Hydroxyphenyl)quinoline exhibited potent antiproliferative activity against the HepG-2 cell lines with an IC₅₀ value of 3.05 μM. Norharmane displayed a moderate inhibition against A549 and HepG-2 cells with IC₅₀ values of 16.45 μM and 17.27 μM, respectively.

Identification of m6A-Associated Gene DST as a Prognostic and Immune-Associated Biomarker in Breast Cancer Patients

Background

N6-methyladenosine (m6A) is most common internal RNA modification in eukaryotic cells. Existing evidence shows that m6A is closely related to pathogenesis and progression in breast cancer (BRCA). Therefore, it is critical to investigate the key role of m6A target genes in BRCA.

Methods

M6A target genes in BRCA are acquired using RMVar online database. The differentially expressed genes (DEGs) from three microarray datasets (GSE5764, GSE22358, GSE9014) is processed by GEO2R. Oncomine, GEPIA, UALCAN and TNMplot were applied to validate the expression of DST. Survival analyses were performed via DRUGSURV and Kaplan–Meier Plotter database. Univariable survival and multivariate Cox analysis were completed to assess the prognostic value of DST and receiver operating characteristic (ROC) curve was performed to evaluate the diagnostic value of DST. We also investigated the correlation between DST and cancer immune infiltration via using CIBERSORT, TIMER and TISIDB.

Results

DST and COL11A1 were significantly expressed in both DEGs and m6A target genes set. COL11A1 show no significance on the patients’ survival. However, high expression of DST was related to the favorable prognosis. Multivariate analysis revealed that the DST dysregulation is an independent prognostic factor and ROC indicated that the great diagnostic value of DST with AUC of 0.948. Subsequently, immunological analyses showed that DST was significantly associated with various immune infiltration cells, including NK cells, T helper cells and Mast cells. Furthermore, DST was also related with multiple immune checkpoints and chemokines, including LAG3, LMTK3 CD24, CXCL12, KDR and CX3CR1. These results indicated the potential roles of DST in the development of BRCA via altering the immune response.

Conclusion

DST can influence the development and progression of BRCA by altering the immune microenvironment.

Vulpinic acid as a natural compound inhibits the proliferation of metastatic prostate cancer cells by inducing apoptosis

BACKGROUND

Lichen secondary metabolites have drawn considerable attention in recent years due to the limitations of current treatment options. Vulpinic acid (VA) obtained from Letharia vulpina lichen species exerts a remarkable cytotoxic effect on different cancer types. However, the therapeutic efficacy of VA in metastatic prostate cancer (mPC) cells has not been investigated. In the present study, we aimed to identify VA-mediated cytotoxicity in PC-3 mPC cells compared with control cells.

METHODS AND RESULTS

After identifying the cytotoxic concentrations of VA, VA induced apoptosis was analyzed by Annexin V, cell cycle, acridine orange and propidium iodide staining and RT-PCR analysis. Our findings showed that VA significantly decreased the viability of PC-3 cells (p < 0.01) and caused a considerable early apoptotic effects through G0/G1 arrest, nuclear blebbing and the activation of particularly initiator caspases.

CONCLUSIONS

Therefore, VA may be a potential treatment option for mPC patients. However, the underlying molecular mechanisms of VA-induced apoptosis with advanced analysis should be further investigated.