2,2- dimethylbenzopyran derivatives containing pyridone structural fragments as selective dual-targeting inhibitors of HIF-1α and EZH2 for the treatment of lung cancer.

We formerly reported that EZH2 inhibitors sensitized HIF-1 inhibitor-resistant cells and inhibited HIF-1α to promote SUZ12 transcription, leading to enhanced EZH2 enzyme activity and elevated H3K27me3 levels, and conversely, inhibition of EZH2 promoted HIF-1α transcription. HIF-1α and EZH2 interacted to form a negative feedback loop that reinforced each other's activity. In this paper, a series of 2,2- dimethylbenzopyran derivatives containing pyridone structural fragments were designed and synthesized with DYB-03, a HIF-1α inhibitor previously reported by our group, and Tazemetostat, an EZH2 inhibitor approved by FDA, as lead compounds. Among these compounds, D-01 had significant inhibitory activities on HIF-1α and EZH2. In vitro experiments showed that D-01 significantly inhibited the migration of A549 cells, clone, invasion and angiogenesis. Moreover, D-01 had good pharmacokinetic profiles. All the results about compound D-01 could lay a foundation for the research and development of HIF-1α and EZH2 dual-targeting compounds.

Design and Synthesis of Dual-Targeting Inhibitors of sEH and HDAC6 for the Treatment of Neuropathic Pain and Lipopolysaccharide-Induced Mortality.

Epoxyeicosatrienoic acids with anti-inflammatory effects are inactivated by soluble epoxide hydrolase (sEH). Both sEH and histone deacetylase 6 (HDAC6) inhibitors are being developed as neuropathic pain relieving agents. Based on the structural similarity, we designed a new group of compounds with inhibition of both HDAC6 and sEH and obtained compound M9. M9 exhibits selective inhibition of HDAC6 over class I HDACs in cells. M9 shows good microsomal stability, moderate plasma protein binding rate, and oral bioavailability. M9 exhibited a strong analgesic effect in vivo, and its analgesic tolerance was better than gabapentin. M9 improved the survival time of mice treated with lipopolysaccharide (LPS) and reversed the levels of inflammatory factors induced by LPS in mouse plasma. M9 represents the first sEH/HDAC6 dual inhibitors with in vivo antineuropathic pain and anti-inflammation.

The Interplay Between HIF-1α and EZH2 in Lung Cancer and Dual-Targeted Drug Therapy.

Interactions between oncogenic proteins contribute to the phenotype and drug resistance. Here, EZH2 (enhancer of zest homolog 2) is identified as a crucial factor that mediates HIF-1 (hypoxia-inducible factor) inhibitor resistance. Mechanistically, targeting HIF-1 enhanced the activity of EZH2 through transcription activation of SUZ12 (suppressor of zest 12 protein homolog). Conversely, inhibiting EZH2 increased HIF-1α transcription, but not the transcription of other HIF family members. Additionally, the negative feedback regulation between EZH2 and HIF-1α is confirmed in lung cancer patient tissues and a database of cell lines. Moreover, molecular prediction showed that a newly screened dual-target compound, DYB-03, forms multiple hydrogen bonds with HIF-1α and EZH2 to effectively inhibit the activity of both targets. Subsequent studies revealed that DYB-03 could better inhibit migration, invasion, and angiogenesis of lung cancer cells and HUVECs in vitro and in vivo compared to single agent. DYB-03 showed promising antitumor activity in a xenograft tumor model by promoting apoptosis and inhibiting angiogenesis, which could be almost abolished by the deletion of HIF-1α and EZH2. Notably, DYB-03 could reverse 2-ME2 and GSK126-resistance in lung cancer. These findings clarified the molecular mechanism of cross-regulation of HIF-1α and EZH2, and the potential of DYB-03 for clinical combination target therapy.

Design, synthesis and evaluation of the novel chalcone derivatives with 2,2-dimethylbenzopyran as HIF-1 inhibitors that possess anti-angiogenic potential.

Hypoxia-inducible factor-1 (HIF-1) as a key mediator in tumor metastasis, angiogenesis and poor patient prognosis, has been recognized as an important cancer drug target. Up to now, some HIF-1 inhibitors with diverse skeletal structures were reported as anticancer agents, mostly natural product-derived compounds. In this study, we designed and synthesized a series of chalcone-based compounds with 2,2-dimethylbenzopyran using the combination principles to select benzopyrans and chalcones natural products. A novel series of chalcone-based compounds with 2,2-dimethylbenzopyran were evaluated as HIF-1 inhibitor. HRE luciferase reporter assay demonstrated compounds showed superior HIF-1 inhibitory activity. Among them, compound 16e exhibited the best features: the strongest HIF-1 inhibitory activity (IC50 = 2.38 µM, 3-fold higher than that of LXH-SYP-7). Meanwhile, it also significantly suppressed migration and VEGF-induced invasion of A549 cells in nontoxic concentrations. Additionally, tube formation assay demonstrated its anti-angiogenesis activity. Moreover, the in vivo study indicated that compound 16e could retard angiogenesis in the matrigel plug assay model, and almost no new blood vessels were formed in the suppository when it reached 20 µM. Finally, we also performed a subchronic toxicity test in which doses up to 50 mg/kg were administered orally for 10 days in Kunming mice with no toxic adverse effects and were well tolerated. These findings support the further investigation on the anti-invasive and anti-angiogenic potential of this class of compounds as HIF-1 inhibitor.

Structure-Directed Discovery of Potent Soluble Epoxide Hydrolase Inhibitors for the Treatment of Inflammatory Diseases.

Soluble epoxide hydrolase (sEH) has been identified as an attractive target for anti-inflammatory drug design in recent years. Picomolar level compound G1 against sEH was obtained by introducing the hydrophilic group homopiperazine and hydrophobic fragment propionyl onto the structure of lead compound A. G1 showed good microsomal stability, a moderate plasma protein binding rate, and good oral bioavailability and was well tolerated in rats. G1 has significant analgesic effects on CFA-induced AIA mice, ameliorated the pancreatic injury in acute pancreatitis induced by l-arginine, reversed pancreatic injury, edema, and neutrophil infiltration, and increased the survival time of C57BL/6 mice in a lipopolysaccharide (LPS)-induced sepsis model. Moreover the expression levels of sEH, COX-2, NOS-2, vascular cell adhesion molecule (VCAM), IL-6, MCP-5, and tumor necrosis factor α (TNF-α) were measured by Western blot or enzyme-linked immunosorbent assay (ELISA), with varying degrees of decrease. These results suggested that G1 is a drug candidate worthy of further evaluation for the treatment of inflammation-induced diseases such as arthritis, acute pancreatitis, and sepsis.