Docosahexaenoic acid induces autophagy through p53/AMPK/mTOR signaling and promotes apoptosis in human cancer cells harboring wild-type p53

作者：Jing Kaipeng; Song Kyoung Sub; Shin Soyeon; Kim Nayeong; Jeong Soyeon; Oh Hye Rim; Park Ji Hoon; Seo Kang Sik; Heo Jun Young; Han Jeongsu; Park Jong Il; Han Chang; Wu Tong; Kweon Gi Ryang; Park Seung Kiel; Yoon Wan Hee; Hwang Byung Doo; Lim Kyu^*

来源：Autophagy, 2011, 7(11): 1348-1358.

DOI：10.4161/auto.7.11.16658

• DHA
• autophagy
• apoptosis
• p53
• cancer
• mTOR
• AMPK
• p27

Docosahexaenoic acid (DHA) has been reported to induce tumor cell death by apoptosis. However, little is known about the effects of DHA on autophagy, another complex well-programmed process characterized by the sequestration of cytoplasmic material within autophagosomes. Here we show that DHA increased both the level of microtubule-associated protein 1 light chain 3 and the number of autophagic vacuoles without impairing autophagic vesicle turnover, indicating that DHA induces not only apoptosis but also autophagy. We also observed that DHA-induced autophagy was accompanied by p53 loss. Inhibition of p53 increased DHA-induced autophagy and prevention of p53 degradation significantly led to the attenuation of DHA-induced autophagy, suggesting that DHA-induced autophagy is mediated by p53. Further experiments showed that the mechanism of DHA-induced autophagy associated with p53 attenuation involved an increase in the active form of AMP-activated protein kinase and a decrease in the activity of mammalian target of rapamycin. In addition, compelling evidence for the interplay between autophagy and apoptosis induced by DHA is supported by the findings that autophagy inhibition suppressed apoptosis and further autophagy induction enhanced apoptosis in response to DHA treatment. Overall, our results demonstrate that autophagy contributes to the cytotoxicity of DHA in cancer cells harboring wild-type p53.

• 出版日期2011-11