title: CDK5RAP1 deficiency induces cell cycle arrest and apoptosis in human breast cancer cell line by the ROS/JNK signaling pathway.
abstract: Cyclin-dependent kinase 5 regulatory subunit associated protein 1 (CDK5RAP1) is an enzyme which post-synthetically converts the RNA modification N6-iso-pentenyladenosine (i6A) into 2-methylthio-N6-isopentenyladenosine (ms2i6A). However, the interaction between CDK5RAP1 deficiency and cell apoptosis has not been studied. Breast cancer has long been a leading cause of mortality in the world. Therefore, in the present study, CDK5RAP1 deficiency in a human breast cancer cell line was investigated. CDK5RAP1 small interfering RNA (siRNA) and negative control siRNA were transfected into MCF-7 cells, and the cells were further incubated for 48 h. CDK5RAP1 deficiency suppressed tumor growth in MCF-7 cells and arrested the cells at G2/M phase. CDK5RAP1 deficiency also induced cell apoptosis and reactive oxygen species (ROS) generation. Furthermore, western blot analysis showed that the expression of phospho-c-Jun N-terminal kinase (p-JNK), p53, caspase-9 and caspase-3 were upregulated in CDK5RAP1-deficient MCF-7 cells. Pretreatment with N-acetyl-cysteine (NAC), the inhibitor of ROS, or with SP600125, the inhibitor of JNK, prevented the apoptosis and the high expression of p-JNK, p53, caspase-9 and caspase-3 in CDK5RAP1-deficient MCF-7 cells. Taken together, these data indicated that CDK5RAP1 deficiency induced cell cycle arrest and apoptosis in human breast cancer MCF-7 cells by the ROS/JNK signaling pathway. Our findings indicated a novel therapeutic strategy for cancer.
authors.affiliation: Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang 150081, P.R. China.
authors.forename: Hongbin
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang 150081, P.R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Wei
authors.affiliation: Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang 150081, P.R. China.
authors.forename: Changli
authors.initials: C
authors.lastname: Li
authors.affiliation: Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang 150081, P.R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang 150081, P.R. China.
authors.forename: Zhigao
authors.initials: Z
authors.lastname: Li
mesh_terms: D017209:Apoptosis / Q000502:physiology*; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D059447:Cell Cycle Checkpoints / Q000502:physiology*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D020935:MAP Kinase Signaling System / Q000502:physiology*; D061986:MCF-7 Cells; D009419:Nerve Tissue Proteins / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D034741:RNA, Small Interfering / Q000037:antagonists & inhibitors; D017382:Reactive Oxygen Species / Q000378:metabolism; D014162:Transfection; D019885:Sulfur Group Transferases; D024101:Mitochondrial Proteins
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; C405930:CDK5RAP1 protein, human; D019885:Sulfur Group Transferases; D024101:Mitochondrial Proteins