Quercetin is a natural flavonoid phytochemical that is extracted from various plants. Having an advantages due to its varied biological properties, such as anti-inflammatory, anti-viral, anti-oxidant, and anti-cancer effects, quercetin is used to treat many diseases. Recently, it has been reported that autophagy inhibition may play a key role in anti-cancer therapy. Therefore, in this study, we investigated the molecular mechanisms and anti-cancer effects of quercetin in human osteosarcoma cells via autophagy inhibition. We ascertained that quercetin inhibited cell proliferation and induced cell death, these process is demonstrated that apoptosis via the mitochondrial pathway and the caspase cascade. Quercetin also induced autophagy which was inhibited by 3-MA, autophagy inhibitor and the blockade of autophagy promoted the quercetin-induced apoptosis, confirming that autophagy is a pro-survival process. Thus, these findings demonstrate that quercetin is an effective anti-cancer agent, and the combination of quercetin and an autophagy inhibitor should enhance the effect of anti-cancer therapy.

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 Materials and Methods
 Results
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 Conflict of interest
 References

• Sung-Jin Park(Department of Oral Anatomy, School of Dentistry, Pusan National Universit)
• Su-Bin Yu(Department of Oral Anatomy, School of Dentistry, Pusan National University)
• Yong-Ho Kim(Department of Oral Anatomy, School of Dentistry, Pusan National University)
• In-Ryoung Kim(Department of Oral Anatomy, School of Dentistry, Pusan National University)
• Hae-Ryoun Park(Department of Oral Pathology, School of Dentistry, Pusan National University)
• ong-Soo Park(Department of Oral Anatomy, School of Dentistry, Pusan National University) Correspondence to