2 research outputs found
Sensitizing Tumors to Immune Checkpoint Blockage via STING Agonists Delivered by Tumor-Penetrating Neutrophil Cytopharmaceuticals
Immune
checkpoint inhibitors (ICIs) have displayed potential efficacy
in triple-negative breast cancer (TNBC) treatment, while only a minority
of patients benefit from ICI therapy currently. Although activation
of the innate immune stimulator of interferon genes (STING) pathway
potentiates antitumor immunity and thus sensitizes tumors to ICIs,
the efficient tumor penetration of STING agonists remains critically
challenging. Herein, we prepare a tumor-penetrating neotype neutrophil
cytopharmaceutical (NEs@STING-Mal-NP) with liposomal STING agonists
conjugating on the surface of neutrophils, which is different from
the typical neutrophil cytopharmaceutical that loads drugs inside
the neutrophils. We show NEs@STING-Mal-NP that inherit the merits
of neutrophils including proactive tumor vascular extravasation and
tissue penetration significantly boost the tumor penetration of STING
agonists. Moreover, the backpacked liposomal STING agonists can be
released in response to hyaluronidase rich in the tumor environment,
leading to enhanced uptake by tumor-infiltrating immune cells and
tumor cells. Thus, NEs@STING-Mal-NP effectively activate the STING
pathway and reinvigorate the tumor environment through converting
macrophages and neutrophils to antitumor phenotypes, promoting the
maturation of dendritic cells, and enhancing the infiltration and
tumoricidal ability of T cells. Specifically, this cytopharmaceutical
displays a significant inhibition on tumor growth and prolongs the
survival of TNBC-bearing mice when combined with ICIs. We demonstrate
that neutrophils serve as promising vehicles for delivering STING
agonists throughout solid tumors and the developed neutrophil cytopharmaceuticals
with backpacked STING agonists exhibit huge potential in boosting
the immunotherapy of ICIs
Novel β‑Carboline/Hydroxamic Acid Hybrids Targeting Both Histone Deacetylase and DNA Display High Anticancer Activity via Regulation of the p53 Signaling Pathway
A novel
series of hybrids from β-carboline and hydroxamic
acid were designed and synthesized. Several compounds (<b>5m</b>, <b>11b</b>–<b>d</b>, and <b>11h</b>) not
only exerted significant antiproliferation activity against four human
colorectal cancer (CRC) cell lines but also showed histone deacetylase
inhibitory effects in vitro. The most potent compound, <b>11c</b>, exhibited anticancer potency sevenfold higher than that of SAHA. <b>11c</b> triggered more significant cancer cell apoptosis than
did SAHA by cleavage of both PARP and caspase 3 in a dose-dependent
manner. Furthermore, <b>11c</b> simultaneously increased the
acetylation of histone H3 and α-tubulin, enhanced expression
of DNA damage markers histone H2AX phosphorylation and p-p53 (Ser15),
and activated p53 signaling pathway in HCT116 cells. Finally, <b>11c</b> showed low acute toxicity in mice and inhibited the growth
of implanted human CRC in mice more potently than did SAHA. Together, <b>11c</b> possessed potent antitumor activity and may be a promising
candidate for the potential treatment of human CRC