The interaction between tumor cells and their immunosuppressive microenvironment promotes tumor progression and drug resistance. Thus, simultaneously targeting tumor cells and stromal cells is expected to have synergistic antitumor effects. Herein, we present for the first time a preclinical antitumor investigation of 3D185, a novel dual inhibitor targeting FGFRs, which are oncogenic drivers, and CSF-1R, which is the major survival factor for protumor macrophages. The antitumor characteristics of 3D185 were assessed by a range of assays, including kinase profiling, cell viability, cell migration, immunoblotting, CD8+ T cell suppression, and in vivo antitumor efficacy, followed by flow cytometric and immunohistochemical analyses of tumor-infiltrating immune cells and endothelial cells in nude mice and immune-competent mice. 3D185 significantly inhibited the kinase activity of FGFR1/2/3 and CSF-1R, with equal potency and high selectivity over other kinases. 3D185 suppressed FGFR signaling and tumor cell growth in FGFR-driven models both in vitro and in vivo. In addition, 3D185 could inhibit the survival and M2-like polarization of macrophages, reversing the immunosuppressive effect of macrophages on CD8+ T cells as well as CSF1-differentiated macrophage induced-FGFR3-aberrant cancer cell migration. Furthermore, 3D185 inhibited tumor growth via remodeling the tumor microenvironment in TAM-dominated tumor models. 3D185 is a promising antitumor candidate drug that simultaneously targets tumor cells and their immunosuppressive microenvironment and has therapeutic potential due to synergistic effects. Our study provides a solid foundation for the investigation of 3D185 in cancer patients, particularly in patients with aberrant FGFR and abundant macrophages, who respond poorly to classic pan-FGFRi treatment.

A series of compounds containing a novel 3-carboxypiperidin-2-one scaffold based on the lead structure BMS-777607 were designed, synthesized and evaluated for their c-Met kinase inhibition and cytotoxicity against MKN45 cancer cell lines. The results indicated that five compounds exhibited significant inhibitory effect on c-Met with IC₅₀ values of 8.6−81 nM and four compounds showed potent inhibitory activity against MKN45 cell proliferation, with IC₅₀s ranging from 0.57−16 μM.

Tumor-associated macrophages (TAMs) are pivotal for tumor development and progression. Reprogramming the M2-like pro-tumoral behavior of TAMs towards the M1-like anti-tumor phenotype to unleash their potential against tumors has become one of the most promising anti-tumor immunotherapy strategies. In this work, the natural product pseudolaric acid B (PAB, 1) was found to markedly decrease ARG1 mRNA expression and significantly increase NOS2 expression in the IL-4/IL-13-pre-stimulated RAW 264.7 cells through cellular phenotype screening of a series of pseudolaric acid-related natural products, suggesting its potential to reprogram the pro-tumoral TAMs towards the M1-like phenotype against tumors. Further chemical modification of the carboxylic acid moiety of 1 led to a series of amide or pyranoside derivatives with ARG1- and NOS2-modulating activity. Among them, hydrazineyl amide 12 stands out as the most potent, without significant diminution in cell viability. It inhibited the M2-like polarized tumor-promoting phenotype of macrophages, as evidenced by a decrease in CD206 expression and an increase in CD86 expression in flow cytometry, as well as a decrease in ARG1 protein level in Western blot assays. In addition, 12 could reverse the suppression of Ki67+, IFN γ+, and granzyme B⁺ CD8⁺ T cell proliferation and activation induced by pro-tumoral macrophages. More importantly, it could reshape the tumor immune microenvironment and inhibit tumor growth in immunocompetent murine tumor models. Hsp90 was predicted to be a potential target of 12 by a target fishing software, which was further demonstrated by molecular docking. Collectively, the amide derivative 12 of PAB demonstrated promising anti-tumor TAM-reprogramming activity, which is worthy of further investigation.

Sesterterpenoids are a very rare class of important natural products. Three new skeletal spiro sesterterpenoids, named orientanoids A–C (1–3), were isolated from Hedyosmum orientale. Their structures were determined by a combination of spectroscopic data, X-ray crystallography, and total synthesis. To obtain adequate materials for biological research, the bioinspired total syntheses of 1–3 were effectively achieved in 7–8 steps in the overall yields of 2.3–6.4% from the commercially available santonin without using any protecting groups and transition-metal catalysts, which mimicked their biosynthetic proposal chemically. In addition, this work also revised hedyosumins B (7) and C (8) as 11R-configuration. Tumor-associated macrophages (TAMs) have emerged as important therapeutic targets in cancer therapy. The in-depth biological evaluation revealed that these sesterterpenoids antagonized the protumoral and immunosuppressive functional phenotype of macrophages in vitro. Among them, the most potent and major compound 1 inhibited protumoral M2-like macrophages and activated cytotoxic CD8+ T cells, and consequently contained tumor growth in vivo.