Anti-tumor efficacy of phellamurin in osteosarcoma cells: Involvement of the PI3K/AKT/mTOR pathway.

The extracts of Phellodendron amurense (P. amurense) have been shown to contain many active ingredients e.g. flavone glycosides and to exert a wide range of physiological activities including anti-tumor activity. However, the effects of phellamurin (Phe), a plant flavonone glycoside from the leaves of P. amurense, on osteosarcoma (OS) have never been reported. The effects of Phe on cell viability and apoptosis were evaluated by MTT assay and flow cytometry analysis, respectively. Western blot analysis was performed to detect the protein levels of phosphorylated phosphatidylinositol 3 kinase (PI3K) (p-PI3K), phosphorylated protein kinase B (AKT) (p-AKT), AKT, phosphorylated mammalian target of rapamycin (mTOR) (p-mTOR), and mTOR. We found that Phe suppressed the viability and promoted apoptosis in OS cells in a dose-dependent manner. Notably, Phe repressed the PI3K/AKT/mTOR pathway in OS cells. LY294002 effectively inhibited the PI3K/AKT/mTOR signaling pathway, repressed cell viability and induced apoptosis in OS cells. Activation of PI3K/AKT/mTOR pathway by 740Y-P abolished the effects of Phe on the viability and apoptosis of OS cells. We also found that Phe repressed OS tumor growth and inhibited the PI3K/AKT/mTOR pathway in vivo. In conclusion, Phe suppressed the viability and induced apoptosis in OS cells, at least, partially by inhibiting the PI3K/AKT/mTOR pathway. Our study suggested that Phe might be a new and potential chemotherapeutic agent for the treatment of OS.

Zhang H ，Jiang H ，Zhang H ，Liu J ，Hu X ，Chen L ... -  《-》

Calycosin, a Phytoestrogen Isoflavone, Induces Apoptosis of Estrogen Receptor-Positive MG-63 Osteosarcoma Cells via the Phosphatidylinositol 3-Kinase (PI3K)/AKT/Mammalian Target of Rapamycin (mTOR) Pathway.

Sun H ，Yin M ，Qian W ，Yin H ... -  《MEDICAL SCIENCE MONITOR》

Pro-apoptotic and pro-autophagic effects of the Aurora kinase A inhibitor alisertib (MLN8237) on human osteosarcoma U-2 OS and MG-63 cells through the activation of mitochondria-mediated pathway and inhibition of p38 MAPK/PI3K/Akt/mTOR signaling pathway.

Niu NK ，Wang ZL ，Pan ST ，Ding HQ ，Au GH ，He ZX ，Zhou ZW ，Xiao G ，Yang YX ，Zhang X ，Yang T ，Chen XW ，Qiu JX ，Zhou SF ... -  《Drug Design Development and Therapy》

MicroRNA‑22 mediates the cisplatin resistance of osteosarcoma cells by inhibiting autophagy via the PI3K/Akt/mTOR pathway.

Meng CY ，Zhao ZQ ，Bai R ，Zhao W ，Wang YX ，Xue HQ ，Sun L ，Sun C ，Feng W ，Guo SB ... -  《-》

Anti-tumoral potential of MDA19 in human osteosarcoma via suppressing PI3K/Akt/mTOR signaling pathway.

Osteosarcoma (OS) is the most common primary malignancy of skeleton with higher mortality rates amongst children and young adults worldwide, whereas effective and secure therapies have also been sought by researches with ongoing efforts. The purpose of the present study was to investigate the impact of N'-[(3Z)-1-(1-hexyl)-2-oxo-1,2-dihydro-3H-indol-3-ylidene] benzohydrazide (MDA19) on OS and explore its potential mechanism. Cell Counting Kit-8 (CCK8) and colony formation assay were employed to evaluate the potential effect of MDA19 on U2OS and MG-63 cells proliferation. Moreover, transwell migration and invasion assay were performed to assess the influence of MDA19 on U2OS and MG-63 cells migration and invasion. In addition, Annexin V-FITC/propidium iodide (Annexin V-FITC/PI) staining and flow cytometry were used to examine apoptotic ratio of the U2OS and MG-63 cells. Meanwhile, Western blot analysis was applied to explore change of relevant mechanism proteins in OS cells treated with MDA19. Our study showed that MDA19 had anti-proliferative activity of OS cells in a dose- and time-dependent manner, simultaneously, inhibition of colony formation was also observed in U2OS and MG-63 cells after incubation of MDA19. Besides, MDA19 could significantly inhibit the number of migrated and invaded OS cells and markedly increase the OS cells apoptosis rate. Mechanistically, we detected detectable reductions in apoptosis related proteins, epithelial-mesenchymal transition (EMT)-related proteins and activity of phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling in U2OS and MG-63 cells exposure to MDA19. Overall, the current study indicates in vitro anti-proliferative, anti-metastatic, and pro-apoptotic potential of MDA19 in U2OS and MG-63 cells. Our findings propose a clue for further studies with this compound in preclinical and clinical treatment for OS.

Liu B ，Xu L ，Dai EN ，Tian JX ，Li JM ... -  《-》