Oxymatrine induces mitochondria dependent apoptosis in human osteosarcoma MNNG/HOS cells through inhibition of PI3K/Akt pathway

Abstract

The cytostatic drug from traditional Chinese medicinal herb has acted as a chemotherapeutic agent used in treatment of a wide variety of cancers. Oxymatrine, classified as a quinolizidine alkaloid, is a phytochemical product derived from Sophora flavescens, and has been reported to possess anticancer activities. However, the cancer growth inhibitory effects and molecular mechanisms in human osteosarcoma MNNG/HOS cell have not been well studied. In the present study, the cytotoxic effects of oxymatrine on MNNG/HOS cells were examined by MTT and bromodeoxyuridine (BrdU) incorporation assays. The percentage of apoptotic cells and the level of mitochondrial membrane potential (Δψ m) were assayed by flow cytometry. The levels of apoptosis-related proteins were measured by Western blot analysis or enzyme assay Kit. Our results showed that treatment with oxymatrine resulted in a significant inhibition of cell proliferation and DNA synthesis in a dose-dependent manner, which has been attributed to apoptosis. Furthermore, we found that oxymatrine considerably inhibited the expression of Bcl-2 whilst increasing that of Bax. This promoted mitochondrial dysfunction, leading to the release of cytochrome c from the mitochondria to the cytoplasm, as well as the activation of caspase-9 and -3. Moreover, addition of oxymatrine to MNNG/HOS cells also attenuated phosphatidylinositol 3-kinase (PI3K) ⁄Akt signaling pathway cascade, evidenced by the dephosphorylation of P13K and Akt. Likewise, oxymatrine significantly suppressed tumor growth in female BALB/C nude mice bearing MNNG/HOS xenograft tumors. In addition, no evidence of drug-related toxicity was identified in the treated animals by comparing the body weight increase and mortality. Therefore, these findings should be useful for understanding the apoptotic cellular mechanism mediated by oxymatrine and might offer a therapeutic potential advantage for human osteosarcoma chemoprevention or chemotherapy.

MALAT1 promotes the proliferation and metastasis of osteosarcoma cells by activating the PI3K/Akt pathway

“…ERK/mitogen-activated protein kinase (MAPK) and PI3K/ Akt pathway are often aberrantly activated in human cancers and contribute to cell proliferation and metastasis [17,22,23]. As a result, Western blot analysis showed that MALAT1 c Western blots analysis of the ERK/MAPK and PI3K/Akt pathway-related proteins in the U-2 OS cells.…”

Fyn arrests swainsonine-induced apoptosis in 293T cells via Akt and its phosphorylation

“…Studies have proved that inhibition of Akt is involved in apoptosis (Zhang et al, 2013;Won et al, 2014). To identify whether Akt is involved in SW-induced apoptosis through overexpression of Fyn, we examined Akt and its phosphorylation at residue 473.…”

A map describing the association between effective components of traditional Chinese medicine and signaling pathways in cancer cells in vitro and in vivo

“…In human osteosarcoma MNNG/HOS cell line, oxymatrine induces mitochondria dependent apoptosis by inhibiting the PI3K/Akt pathway (15). In an in intro and in vivo experiment, oxymatrine shows an antiangiogenic effect on pancreatic cancer through inhibition of the NF-κB-mediated VEGF signaling pathway (16).…”