Cocktail therapy involves combining two or more drugs to treat a specific disease, while botanical cocktail therapy specifically refers to the method of selecting combinations of two or more botanical

Glioma is the most common primary malignant brain tumor. Despite advances in surgical techniques and treatment regimens, the therapeutic effects of glioma remain unsatisfactory. Immunotherapy has brought new hope to glioma patients, but its therapeutic outcomes are limited by the immunosuppressive nature of the tumor microenvironment (TME). This study aimed to reveal the subpopulations and functional characteristics of tumor-associated macrophages (TAMs) and explore the regulatory effects of CHA on the immune microenvironment, as well as its potential for clinical application.

CHA is a natural product that effectively inhibits tumor growth, demonstrated in many preclinical models, and phase II clinical trials for patients with glioma. However, its direct proteomic targets and anticancer molecular mechanisms remain unknown. Herein, we developed a novel bi-functional photo-affinity probe PAL/CHA and discovered mitochondrial acetyl-CoA acetyltransferase 1 (ACAT1) was one of the main target proteins of CHA by using affinity-based protein profiling (AfBPP) chemical proteomic approach. We performed in-depth studies on ACAT1/CHA interactions via multiple assays including SPR, ITC, and cryo-EM. Importantly, we demonstrated that CHA impaired cancer cell proliferation by inhibiting the phosphorylation of tetrameric ACAT1 on Y407 residue through a novel mode of action in vitro and in vivo. Our study highlights the use of AfBPP platforms in uncovering unique druggable modalities accessed by natural products. And identifying the molecular target of CHA sheds light on the future clinical application of CHA for cancer therapy.

Abnormal differentiation of cells is a hallmark of malignancy. Induction of cancer-cell differentiation is emerging as a novel therapeutic strategy with low toxicity in hematological malignances, but whether such treatment can be used in solid tumors is not known. Here, we uncovered a novel function of acetyl coenzyme A acetyltransferase (ACAT1) in regulating the differentiation of glioblastoma (GBM) cells. Inhibition of ACAT1 promoted the differentiation of GBM cells into astrocytes but also delayed tumor growth. Mechanistically, suppression of ACAT1 restored mitochondrial function and led to metabolic “reprogramming” in GBM cells: reduction of fatty-acid oxidation and acetyl-CoA, but an increase in free fatty acids. Importantly, ACAT1 negatively regulated the choline metabolic pathway, which is crucial for the differentiation of GBM cells. Finally, we demonstrated that a naturally available substance, CHA, could inhibit phosphorylation of ACAT1 and so delay GBM progression, CHA is a promising candidate to treat GBM because it could induce the differentiation of cancer cells.

As immune checkpoint inhibitors have shown good clinical efficacy, immune checkpoint blockade has become a vital strategy in cancer therapy. However, approximately only 12.5% patients experience benefits from immunotherapy. Herein, we identified the cancer differentiation inducer CHA, (now in the phase II clinical trial in China for glioma treatment) to be a small-molecular immune checkpoint inhibitor that boosted the antitumor effects of the anti-PD-1 antibody. CHA suppressed the expression of PD-L1 induced by interferon-γ in tumor cell culture through inhibition of the p-STAT1-IRF1 pathway and enhanced activity of activated T-cells. In two murine tumor xenografts, combination therapy of CHA with anti-PD-1 antibody decreased the expression of PD-L1 and IRF1 and increased the inhibitory effect of the anti-PD-1 antibody on tumor growth. Particularly, the activity of tumor infiltrated T cells was enhanced by CHA. CHA improved the gene expression of granzymes in tumor-infiltrated immune cells. In conclusion, through induction of differentiation, CHA appeared to suppress the expression of PD-L1 on cancer cells, effectively promoting infiltrated T cells in the tumor and boosting the antitumor effect of the anti-PD-1 antibody. Thus, CHA might serve as a promising agent to enhance anticancer immunotherapy if combined with anti-PD-1 antibodies.

CHA has been shown to have substantial biological activities, including anti-inflammatory, antioxidant, and antitumor effects. However, the pharmacological role of CHA in neuroblastoma has not yet been assessed. Neuroblastoma is a type of cancer that develops in undifferentiated sympathetic ganglion cells. This study aims to assess the antitumor activity of CHA against neuroblastoma and reveal its mechanism of action in cell differentiation.