Premium
Pipoxolan exhibits antitumor activity toward oral squamous cell carcinoma cell through the reactive oxygen species mediated apoptosis
Author(s) -
Hsiao JunHan,
Chou PeiYu,
Sheu MingJyh
Publication year - 2017
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.31.1_supplement.670.9
Subject(s) - apoptosis , cytochrome c , reactive oxygen species , annexin , pi3k/akt/mtor pathway , protein kinase b , chemistry , intrinsic apoptosis , microbiology and biotechnology , mtt assay , biology , cancer research , caspase , programmed cell death , biochemistry
Pipoxolan is a well‐known smooth muscle relaxant. However, its apoptotic effects and mechanism in oral squamous cell carcinoma (OSCC) have not been clarified. In the present study, we investigated whether pipoxolan could induce apoptosis in OSCC and explored its potential mechanisms. Cell cytotoxicity were evaluated by MTT assay and apoptosis were measured by Annexin V/PI double staining and flow cytometry analysis. Apoptotic‐related proteins were assessed by Western blotting. Our results demonstrated that pipoxolan treatment caused a time‐dependent decrease the protein expressions of Fas/CD95, cytosolic cytochrome c, active form of caspase‐8, ‐9 and ‐3, hydrolysis of PARP, and Bcl‐2. However, Bax was increased. Clearly, an apoptosis was associated with an increased Bax/Bcl‐2 ratio. Pipoxolan markedly suppressed the expressions of PI3K and phosphorylation of Akt. Reactive oxygen species (ROS) generation and mitochondrial membrane potential (MMP) were measured with fluorescent probes. Furthermore, following exposure of TW206 cells with pipoxolan, a time‐dependently decrease in the MMP and an increase in the ROS. Since high levels of ROS were produced early in the drug treatment, intracellular ROS seemed to play a key role in the pipoxolan‐induced apoptosis. Obviously, apoptosis was significantly abrogated by the free radical scavenger N‐acetyl‐L‐cysteine (NAC). Also, pipoxolan‐induced apoptosis can be blocked by pan‐caspase inhibitor (Z‐VAD‐FMK). The abovementioned data suggested that pipoxolan acted against TW206 and HSC‐3 in vitro via both intrinsic, extrinsic apoptotic signaling pathways, and exhibited in PI3K/Akt signaling pathway. Thus, pipoxolan might be a candidate therapeutic agent for OSCC. Support or Funding Information MOST104‐2320‐ B‐039‐ 007