[Mechanism of polyphyllin â targeting EGFR to affect proliferation and apoptosis of human breast cancer cells].

This study aims to investigate the molecular mechanism of polyphyllin Ⅰ(PPⅠ) inhibiting proliferation of human breast cancer cells. Human breast cancer BT474 and MDA-MB-436 cells were treated with different concentrations of PPⅠ, and then the effect of PPⅠ on cell proliferation was detected by MTT assay, trypan blue dye exclusion assay, real-time cell analysis, and clone forming assay, respectively. The apoptosis was detected by Annexin V-FITC/PI staining and then analyzed by flow cytometry. The change of mitochondrial membrane potential was detected by flow cytometry after fluorescent probe JC-1 staining. Western blot was used to detect protein expression and phosphorylation. Molecular docking was performed to detect the binding between PPⅠ and EGFR. The affinity between PPⅠ and EGFR was determined by drug affinity responsive target stability assay. The results indicated that PPⅠ inhibited the proliferation and colony formation of BT474 and MDA-MB-436 cells in a time-and concentration-dependent manner. The PPⅠ treatment group showed significantly increased apoptosis rate and significantly decreased mitochondrial membrane potential. PPⅠ down-regulated the expression of pro-caspase-3 protein, promoted the cleavage of PARP, and significantly reduced the phosphorylation levels of EGFR, Akt, and ERK. Molecular docking showed that PPⅠ bound to the extracellular domain of EGFR and formed hydrogen bond with Gln366 residue. Drug affinity responsive target stability assay confirmed that PPⅠ significantly prevented pronase from hydrolyzing EGFR, indicating that PPⅠ and EGFR have a direct binding effect. In conclusion, PPⅠ inhibited the proliferation and induced apoptosis of breast cancer cells by targeting EGFR to block its downstream signaling pathway. This study lays a foundation for the further development of PPⅠ-targeted drugs against breast cancer.

Elucidating the role of 4-hydroxy-2(3H)-benzoxazolone in chronic alcoholic liver disease via transcriptomics and metabolomics.

Background: Chronic alcoholic liver disease (CALD) is a global health problem which includes multiple pathological processes such as immune inflammation and oxidative stress. 4-hydroxy-2(3H)-benzoxazolone (HBOA), an alkaloid isolated from Acanthus ilicifolius L, has been shown to exert hepatoprotective and immunomodulatory effects. However, its effects on CALD remain unclear. This study aimed to investigate the effects and underlying mechanisms of HBOA on CALD. Methods: Rats were administered alcohol by gavage continuously for 12 weeks to establish the CALD model, and then treated with HBOA by gavage for 4 weeks. Transcriptomics and metabolomics were used to predict the potential mechanisms of the effects of HBOA on CALD. Liver histology and function, oxidative stress, inflammatory cytokines, and the TLR4/NF-κB pathway components were evaluated. Results: HBOA significantly improved alcohol-induced liver injury and steatosis. It decreased the expression levels of pro-inflammatory cytokines (tumour necrosis factor-α [TNF-α], interleukin (IL)-1ß, and IL-6), and increased the activities of antioxidant enzymes (superoxide dismutase [SOD], glutathione [GSH], and glutathione peroxidase [GSH-Px]). Western blotting confirmed that HBOA treatment largely diminished NF-κBp65 nuclear translocation. Comprehensive transcriptomics and metabolomics analyses indicated that HBOA regulated the glycerophospholipid metabolism pathway to achieve therapeutic effects in rats with CALD. Conclusion: HBOA has a therapeutic effect on rats with CALD. Its mechanism of action mainly affects the glycerophospholipid metabolic pathway to promote lipid metabolism homeostasis by regulating the expression of Etnppl, Gpcpd1, and Pla2g4c. In addition, it may also inhibit the TLR4/NF-κB signaling pathway, thereby reducing the immune-inflammatory response.

Paris saponin VII, a direct activator of AMPK, induces autophagy and exhibits therapeutic potential in non-small-cell lung cancer.

Paris saponin VII (PSVII), a bioactive constituent extracted from Trillium tschonoskii Maxim., is cytotoxic to several cancer types. This study was designed to explore whether PSVII prevents non-small-cell lung cancer (NSCLC) proliferation and to investigate its molecular target. AMP-activated protein kinase (AMPK) has been implicated in the activation of autophagy in distinct tissues. In cultured human NSCLC cell lines, PSVII induces autophagy by activating AMPK and inhibiting mTOR signaling. Furthermore, PSVII-induced autophagy activation was reversed by the AMPK inhibitor compound C. Computational docking analysis showed that PSVII directly interacted with the allosteric drug and metabolite site of AMPK to stabilize its activation. Microscale thermophoresis assay and drug affinity responsive target stability assay further confirmed the high affinity between PSVII and AMPK. In summary, PSVII acts as a direct AMPK activator to induce cell autophagy, which inhibits the growth of NSCLC cells. In the future, PSVII therapy should be applied to treat patients with NSCLC.