Thymus‑expressed chemokine secreted by breast cancer cells promotes metastasis and inhibits apoptosis

Acetyltransferase NAT10 promotes an immunosuppressive microenvironment by modulating CD8+ T cell activity in prostate cancer

N-acetyltransferase 10 (NAT10), an enzyme responsible for ac4C acetylation, is implicated in cancer progression, though its specific biological function in prostate cancer remains insufficiently understood. This study clarifies NAT10's role in prostate cancer and its effects on the tumor immune microenvironment. NAT10 expression and clinical relevance were assessed through bioinformatics, RT-qPCR, and IHC analyses, comparing prostate cancer tissues with normal controls. The impact of NAT10 on tumor cell proliferation, migration, and invasion was investigated via in vitro assays-including CCK-8, EdU, wound healing, and 3D-Transwell-as well as in vivo mouse xenograft models and organoid studies. Further, NAT10's influence on immune cell infiltration was examined using flow cytometry, IHC, cell co-culture assays, and ELISA to elucidate downstream chemokine effects, specifically targeting CD8+ T cells. Findings indicated significant upregulation of NAT10 in prostate cancer cells, enhancing their proliferative and invasive capacities. Notably, NAT10 suppresses CD8+ T cell recruitment and cytotoxicity through the CCL25/CCR9 axis, fostering an immunosuppressive microenvironment that exacerbates tumor progression. An ac4C modification score was also devised based on NAT10's downstream targets, providing a novel predictive tool for evaluating immune infiltration and forecasting immunotherapy responses in patients with prostate cancer. This study underscores NAT10's pivotal role in modulating the prostate cancer immune microenvironment, offering insights into the immune desert phenomenon and identifying NAT10 as a promising therapeutic target for improving immunotherapy efficacy.

Biology of breast cancer brain metastases and novel therapies targeting the blood brain barrier: an updated review

Brain metastasis (BM) is a critical cause of morbidity and mortality in patients with breast cancer (BC). Compared with other cancer cells, BC cells (BCs) exhibit special features in the metastatic process. However, the underlying mechanisms are still unclear, especially the crosstalk between tumour cells and the microenvironment. To date, novel therapies for BM, including targeted therapy and antibody‒drug conjugates, have been developed. Due to an improved understanding of the blood‒brain barrier (BBB) and blood-tumour barrier (BTB), the development and testing of therapeutic agents in clinical phases have substantially increased. However, these therapies face a major challenge due to the low penetration of the BBB or BTB. As a result, researchers have increasingly focused on finding ways to promote drug penetration through these barriers. This review provides an updated overview of breast cancer brain metastases (BCBM) and summarizes the newly developed therapies for BCBM, especially drugs targeting the BBB or BTB.

Oxymatrine inhibits proliferation and apoptosis of human breast cancer cells through the regulation of miRNA-140-5P

OBJECTIVE

Oxymatrine has shown strong anti-cancer ability, but its mechanism is not well-studied.

METHODS

The inhibitory rates of oxymatrine with various concentrations (0, 1, 2, 4, 6, 8, 16, 32 mg/ml) on MCF-7 cells were detected by CCK-8. The effects of oxymatrine on the expression of miRNA-140-5P in MCF-7 cells were detected by real-time fluorescent quantitative PCR (RT-PCR). miRNA-140-5P mimics or NC mimics were transfected into cells using Lipofectamine 2000. Eventually, the cells were divided into control-group, drug-group, miRNA-140-5P mimics group, NC mimics group, and miRNA-140-5P mimics + drug group. Cell viability was detected by CCK-8 assay and apoptosis rate of each group were measured by using Flow cytometry. Western blot was carried out to detect the protein expression of TGFBR1 and FGF9.

RESULTS

Oxymatrine at various concentrations had conspicuous inhibitory effect on the proliferation of MCF-7 cells (P<0.05), and the inhibitory effect of oxymatrine on MCF-7 cells showed both dose- and time-dependent manners. The relative expression of miRNA-140-5P in MCF cells was remarkably lower than that in MCF-10A. Oxymatrine could effectively promote the expression of miRNA-140-5P in MCF-7 cells, and the relative expression of miRNA-140-5P increased significantly with the increased dose of oxymatrine (P<0.05). Both transfection of miRNA-140-5P mimics and oxymatrine treatment could reduce the proliferation of MCF-7 cells (P<0.05), and the proliferation of cells in miRNA-140-5P mimics + drug-group was significantly lower than that of other groups (P<0.05). Compared with the control-group, the protein expressions of TGFbR1 and FGF9 in low-dose, medium-dose and high-dose groups were dramatically decreased (P<0.05), in a dose-dependent manner (P<0.05).

CONCLUSION

Oxymatrine inhibits proliferation and promotes cell apoptosis of breast cancer MCF-7 cells. The mechanism may contribute to the regulation of miRNA-140-5p and its target genes.

An Immune-Related Gene Prognostic Index for Triple-Negative Breast Cancer Integrates Multiple Aspects of Tumor-Immune Microenvironment

Simple Summary

Triple-negative breast cancer (TNBC) is the most refractory subtype of breast cancer. Immune checkpoint inhibitor (ICI) therapy has made progress in TNBC treatment. PD-L1 expression is a useful biomarker of ICI therapy efficacy. However, tumor-immune microenvironment (TIME) factors, such as immune cell compositions and tumor-infiltrating lymphocyte (TIL) status, also influence tumor immunity. Therefore, it is necessary to seek biomarkers that are associated with multiple aspects of TIME in TNBC. In this study, we developed an immune-related gene prognostic index (IRGPI) with a substantial prognostic value for TNBC. Moreover, the results from multiple cohorts reproducibly demonstrate that IRGPI is significantly associated with immune cell compositions, the exclusion and dysfunction of TILs, as well as PD-1 and PD-L1 expression in TIME. Therefore, IRGPI is a promising biomarker closely related to patient survival and TIME of TNBC and may have a potential effect on the immunotherapy strategy of TNBC.

Abstract

Tumor-immune cell compositions and immune checkpoints comprehensively affect TNBC outcomes. With the significantly improved survival rate of TNBC patients treated with ICI therapies, a biomarker integrating multiple aspects of TIME may have prognostic value for improving the efficacy of ICI therapy. Immune-related hub genes were identified with weighted gene co-expression network analysis and differential gene expression assay using The Cancer Genome Atlas TNBC data set (n = 115). IRGPI was constructed with Cox regression analysis. Immune cell compositions and TIL status were analyzed with CIBERSORT and TIDE. The discovery was validated with the Molecular Taxonomy of Breast Cancer International Consortium data set (n = 196) and a patient cohort from our hospital. Tumor expression or serum concentrations of CCL5, CCL25, or PD-L1 were determined with immunohistochemistry or ELISA. The constructed IRGPI was composed of CCL5 and CCL25 genes and was negatively associated with the patient’s survival. IRGPI also predicts the compositions of M0 and M2 macrophages, memory B cells, CD8⁺ T cells, activated memory CD4 T cells, and the exclusion and dysfunction of TILs, as well as PD-1 and PD-L1 expression of TNBC. IRGPI is a promising biomarker for predicting the prognosis and multiple immune characteristics of TNBC.

CC Chemokines in a Tumor: A Review of Pro-Cancer and Anti-Cancer Properties of Receptors CCR5, CCR6, CCR7, CCR8, CCR9, and CCR10 Ligands

CC chemokines (or β-chemokines) are 28 chemotactic cytokines with an N-terminal CC domain that play an important role in immune system cells, such as CD4⁺ and CD8⁺ lymphocytes, dendritic cells, eosinophils, macrophages, monocytes, and NK cells, as well in neoplasia. In this review, we discuss human CC motif chemokine ligands: CCL1, CCL3, CCL4, CCL5, CCL18, CCL19, CCL20, CCL21, CCL25, CCL27, and CCL28 (CC motif chemokine receptor CCR5, CCR6, CCR7, CCR8, CCR9, and CCR10 ligands). We present their functioning in human physiology and in neoplasia, including their role in the proliferation, apoptosis resistance, drug resistance, migration, and invasion of cancer cells. We discuss the significance of chemokine receptors in organ-specific metastasis, as well as the influence of each chemokine on the recruitment of various cells to the tumor niche, such as cancer-associated fibroblasts (CAF), Kupffer cells, myeloid-derived suppressor cells (MDSC), osteoclasts, tumor-associated macrophages (TAM), tumor-infiltrating lymphocytes (TIL), and regulatory T cells (T_reg). Finally, we show how the effect of the chemokines on vascular endothelial cells and lymphatic endothelial cells leads to angiogenesis and lymphangiogenesis.