title: miR-221/222 suppression protects against endoplasmic reticulum stress-induced apoptosis via p27(Kip1)- and MEK/ERK-mediated cell cycle regulation.
abstract: Cancer cells are relatively resistant to endoplasmic reticulum (ER) stress-induced apoptosis. However, the underlying mechanisms remain largely unclear. We observed that the microRNAs miR-221/222 are associated with apoptosis regulation under ER stress in human hepatocellular carcinoma (HCC) cells. Induction of ER stress does not trigger significant apoptosis but obviously causes downregulation of miR-221/222 in HCC cells. In these cells, ER stress-induced apoptosis is enhanced by miR-221/222 mimics and attenuated by miR-221/222 inhibitors. miR-221/222 promoted-apoptosis under ER stress is associated with p27(Kip1)- and MEK/ERK-mediated cell cycle regulation. Our results suggest that suppression of miR-221/222 plays a crucial role in the protection against apoptosis induced by ER stress in HCC cells.
authors.affiliation: Department of Biochemistry of Luzhou Medical College, Luzhou 646000, Sichuan, China.
authors.forename: Rongyang
authors.initials: R
authors.lastname: Dai
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.forename: Youping
authors.initials: Y
authors.lastname: Liu
authors.forename: Dongmei
authors.initials: D
authors.lastname: Yan
authors.forename: Shaokun
authors.initials: S
authors.lastname: Chen
authors.forename: Chunyan
authors.initials: C
authors.lastname: Duan
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Liu
authors.forename: Tao
authors.initials: T
authors.lastname: He
authors.forename: Hong
authors.initials: H
authors.lastname: Li
mesh_terms: D017209:Apoptosis; D002453:Cell Cycle; D050760:Cyclin-Dependent Kinase Inhibitor p27; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D035683:MicroRNAs / Q000378:metabolism*; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism*; D018384:Oxidative Stress; D014407:Tumor Cells, Cultured
chemical_list: D050760:Cyclin-Dependent Kinase Inhibitor p27; D048049:Extracellular Signal-Regulated MAP Kinases; D047908:Intracellular Signaling Peptides and Proteins; D035683:MicroRNAs; D020929:Mitogen-Activated Protein Kinase Kinases; C436291:CDKN1B protein, human; C525709:MIR221, human; C525710:MIR222, human