Qingdong Zhao1, Mingxia Ye1, Wen Yang1, Min Wang1,2, Mingxia Li1, Chenglei Gu1,3, Luyang Zhao4, Zhe Zhang1, Weidong Han5, Wensheng Fan1, Yuanguang Meng1. 1. Department of Gynecology and Obstetrics, People's Liberation Army Medical School, Chinese People's Liberation Army General Hospital, Beijing, China. 2. Department of Gynecology and Obstetrics, the 306th Hospital of Chinese People's Liberation Army, Beijing, China. 3. Department of Gynecology and Obstetrics, the 309th Hospital of Chinese People's Liberation Army, Beijing, China. 4. Department of Gynecology and Obstetrics, Peking University People's Hospital, Beijing, China. 5. Department of Molecular Biology, Institute of Basic Medicine, People's Liberation Army Medical School, Chinese People's Liberation Army General Hospital, Beijing, China.
Abstract
BACKGROUND/AIMS: Mitochondrial homeostasis is implicated in the development and progression of endometriosis through poorly defined mechanisms. Mst1 is the major growth suppressor related to cancer migration, apoptosis and proliferation. However, whether Mst1 is involved in endometriosis apoptosis and migration via regulating the mitochondrial function remains to be elucidated. METHODS: Expression of Mst1 in endometriosis was examined via western blots. Cellular apoptosis was detected via MTT and TUNEL assay. Gain of function assay about Mst1 was conducted via adenovirus over-expression. Mitochondrial functions were evaluated via mitochondrial membrane potential JC-1 staining, ROS flow cytometry analysis, mPTP opening assessment and immunofluorescence of HtrA2/Omi. The mitophagy activity were examined via western blots and immunofluorescence. RESULTS: First, we found that Mst1 was significantly downregulated in the ectopic endometrium of endometriosis compared to the normal endometrium. However, the recovery of Mst1 function was closely associated with the inability of endometrial stromal cells (ESCs) to migrate and survive. A functional study indicated that regaining Mst1 enhanced Drp1 post-transcriptional phosphorylation at Ser616 and repressed Parkin transcription activity via p53, leading to mitochondrial fission activation and mitophagy inhibition. Excessive Drp1-related fission forced the mitochondria to liberate HtrA2/Omi into the cytoplasm. Moreover, Mst1-induced defective mitophagy evoked cellular oxidative stress, energy metabolism and calcium overload. Through excessive mitochondrial fission and aberrant mitophagy, Mst1 launched caspase 9-related mitochondrial apoptosis and abrogated F-actin/lamellipodium-dependent cellular migration. Notably, we also defined NR4A/miR181c as the upstream signal for Mst1 dysfunction in endometriosis. CONCLUSION: Collectively, our results comprehensively described the important role of the NR4A-miR181c-Mst1 pathway in endometriosis, which handled mitochondrial apoptosis and F-actin/ lamellipodium-based migration via the regulation of Drp1-related mitochondrial fission and Parkin-required mitophagy, with a potential application in endometriosis therapy by limiting ESCs migration and promoting apoptosis.
BACKGROUND/AIMS: Mitochondrial homeostasis is implicated in the development and progression of endometriosis through poorly defined mechanisms. Mst1 is the major growth suppressor related to cancer migration, apoptosis and proliferation. However, whether Mst1 is involved in endometriosis apoptosis and migration via regulating the mitochondrial function remains to be elucidated. METHODS: Expression of Mst1 in endometriosis was examined via western blots. Cellular apoptosis was detected via MTT and TUNEL assay. Gain of function assay about Mst1 was conducted via adenovirus over-expression. Mitochondrial functions were evaluated via mitochondrial membrane potential JC-1 staining, ROS flow cytometry analysis, mPTP opening assessment and immunofluorescence of HtrA2/Omi. The mitophagy activity were examined via western blots and immunofluorescence. RESULTS: First, we found that Mst1 was significantly downregulated in the ectopic endometrium of endometriosis compared to the normal endometrium. However, the recovery of Mst1 function was closely associated with the inability of endometrial stromal cells (ESCs) to migrate and survive. A functional study indicated that regaining Mst1 enhanced Drp1 post-transcriptional phosphorylation at Ser616 and repressed Parkin transcription activity via p53, leading to mitochondrial fission activation and mitophagy inhibition. Excessive Drp1-related fission forced the mitochondria to liberate HtrA2/Omi into the cytoplasm. Moreover, Mst1-induced defective mitophagy evoked cellular oxidative stress, energy metabolism and calcium overload. Through excessive mitochondrial fission and aberrant mitophagy, Mst1 launched caspase 9-related mitochondrial apoptosis and abrogated F-actin/lamellipodium-dependent cellular migration. Notably, we also defined NR4A/miR181c as the upstream signal for Mst1 dysfunction in endometriosis. CONCLUSION: Collectively, our results comprehensively described the important role of the NR4A-miR181c-Mst1 pathway in endometriosis, which handled mitochondrial apoptosis and F-actin/ lamellipodium-based migration via the regulation of Drp1-related mitochondrial fission and Parkin-required mitophagy, with a potential application in endometriosis therapy by limiting ESCs migration and promoting apoptosis.