Oxoaporphine Pr(III) complex inhibits hepatocellular carcinoma progression and metastasis by disrupting tumor cell-macrophage crosstalk.

Tumor cells and macrophages communicate through the secretion of various cytokines to jointly promote the malignant development of cancers. We synthesized and characterized an oxoaporphine Pr(III) complex (PrL3(NO3)3) and found that it inhibits hepatocellular carcinoma (HCC) progression and metastasis by disrupting HCC cell-macrophage crosstalk. PrL3(NO3)3 treatment upregulated CD86, TNF-α, and IL-1ß and downregulated CD163, CD206, CCL2, and VEGFA in macrophages. Our mRNA-Seq results demonstrated that PrL3(NO3)3 inhibited macrophage M2-like polarization by inhibiting the AMPK pathway and activating the NF-κB pathway by upregulating RelA/p65 Ser536 phosphorylation. This kind of macrophage polarization significantly inhibited HCC cell proliferation, migration, and invasion. In addition, PrL3(NO3)3 inhibited the migration, invasion, and chemotaxis of HCC cells by downregulating the expression of EMT-related markers and CCL2. hTFtarget database analysis revealed that PrL3(NO3)3 inhibited NF-κB nuclear translocation by upregulating RelA/p65 Ser536 phosphorylation in HCC cells, thereby downregulating the expression of Snail and CCL2. HCC tissue microarray analysis revealed that downregulation of RelA/p65 Ser536 phosphorylation is a driving event in HCC malignant progression. In conclusion, PrL3(NO3)3 effectively inhibits HCC cell-macrophage crosstalk by upregulating RelA/p65 Ser536 phosphorylation. This is the first report of a lanthanide complex exerting regulatory effects on both tumors and tumor-associated macrophages, providing a new strategy for the development of effective antitumor drugs.

Potent Zinc(II)-Based Immunogenic Cell Death Inducer Triggered by ROS-Mediated ERS and Mitochondrial Ca2+ Overload.

Zn1 and Zn2 are Zn-based complexes that activate the immunogenic cell death (ICD) effect by Ca2+-mediated endoplasmic reticulum stress (ERS) and mitochondrial dysfunction. Compared with Zn1, Zn2 effectively caused reactive oxidative species (ROS) overproduction in the early phase, leading to ERS response. Severe ERS caused the release of Ca2+ from ER to cytoplasm and further to mitochondria. Excessive Ca2+ in mitochondria triggered mitochondrial dysfunction. The damage-associated molecular patterns (DAMPs) of CRT, HMGB1, and ATP occurred in T-24 cells exposed to Zn1 and Zn2. The vaccination assay demonstrated that Zn1 and Zn2 efficiently suppressed the growth of distant tumors. The elevated CD8+ cytotoxic T cells and decreased Foxp3+ cells in vaccinated mice supported our conclusion. Moreover, Zn1 and Zn2 improved the survival rate of mice compared with oxaliplatin. Collectively, our findings provided a new design strategy for a zinc-based ICD inducer via ROS-induced ERS and mitochondrial Ca2+ overload.

One-pot synthesis of oxoaporphines as potent antitumor agents and investigation of their mechanisms of actions.

An efficient one-pot reaction for the synthesis of oxoaporphine alkaloids has been developed. Twenty-three compounds of oxoaporphine alkaloids were prepared and assessed for their antitumor activities. Most compounds inhibited the growth of T-24 tumor cells in vitro. Particularly, 4B displayed the most potent activity with an IC50 value of 0.5 µM, which was 19-fold more potent than the parent compound 4. The substitution at C3-position of oxoaporphine core by -NO2 significantly enhanced the anticancer activity. Mechanism studies indicated that 4 and 4B induced cell cycle arrest at G2/M phase; in contrast, 4V induced cell cycle arrest at the S phase. Increase of mitochondrial ROS/Ca2+ and decrease of MMP, accompanied by activation of caspase-3/9, were observed in T-24 cells after exposure to compounds 4, 4B and 4V, suggesting that the mitochondrial pathway was involved in the induced apoptosis. Moreover, compound 4B effectively inhibited tumor growth in a mouse xenograft model bearing T-24.