Qilan Preparation Inhibits Proliferation and Induces Apoptosis by down-regulating microRNA-21 in Human Tca8113 Tongue Squamous Cell Carcinoma Cells

Abstract Background: Qilan preparation, a complex Chinese herbal medicine consisting of ingredients extracted from Radix Astragali, Gynostemma Pentaphyllum, Rhizoma Chuanxiong and selenium- rich green tea and known for ‘fortifying the spleen and boosting qi, quickening the blood and transforming stasis, and resolving toxins and relieving pain, is used for the prevention and management of oral diseases. The aim of this study was to examine the antitumor effects of Qilan preparation on oral squamous cell carcinoma (OSCC) in vitro and to explore its underlying mechanisms of action. Methods: Human Tca8113 tongue squamous cell carcinoma (TSCC) cells were tested. Cell proliferation, cell cycle distribution and apoptosis were examined using cell counting kit-8 (CCK8) and flow cytometry (FCM). The expression of PTEN and PDCD4 were determined by western blot. Changes in miR-21 levels were quantified using TaqMan stem-loop real-time PCR. After miR-21 was transiently transfected into Tca8113 cells using Lipofectamine®3000, cell proliferation, apoptosis and miR-21 and PDCD4 expression levels were measured.Results: Qilan preparation inhibited Tca8113 cell growth in a dose- and time-dependent manner by inducing apoptosis and cell cycle arrest in S-phase, decreasing miR-21 levels and increasing PTEN and PDCD4 expression. MiR-21 overexpression reversed the Qilan preparation-induced suppression of cell proliferation and induction of apoptosis while also blocking the increase in PDCD4.Conclusions: Our study revealed, for the first time, the ability of Qilan preparation to suppress TSCC cell growth and elucidated that Qilan preparation elicits its anti-cancer actions via either the miR-21/PDCD4 or PTEN pathway.