title: MicroRNA-216b/Beclin 1 axis regulates autophagy and apoptosis in human Tenon's capsule fibroblasts upon hydroxycamptothecin exposure.
abstract: Proliferation and fibrosis of human Tenon's fibroblasts (HTFs) have significantly challenged the outcome of glaucoma filtration surgery. Hydroxycamptothecin (HCPT) is considered as a potential chemical to overcome this issue as it was previously shown that HCPT inhibited cell proliferation and induced apoptosis in fibroblasts. Here, we further dissected the molecular pathway, through which the HCPT inhibit the proliferation of HTFs. We showed that HCPT induced significant autophagy as well as apoptosis, two self-destructive processes, and down-regulated the expression of miR-216b in HTFs. Overexpression of miR-216b in HTFs suppressed the autophagy and apoptosis induced by HCPT, whereas silence of miR-216b led to effects that were similar to those caused by the treatment with HCPT. Further, we showed that miR-216b could directly target a specific fragment in the 3' untranslated region of Beclin 1 as demonstrated by luciferase assay, and consequently decreased the expression of Beclin 1. Consistently, knocking down Beclin 1 significantly decreased HCPT-triggered autophagy and apoptosis, and increased the viability of HTFs treated with HCPT, thus implicating that Beclin 1 functions as a pro-apoptotic molecule in this circumstance. Altogether, we concluded that miR-216b regulated both autophagy and apoptosis by modulating Beclin 1 in HTFs treated with HCPT. We also demonstrated that HCPT-induced autophagy is one of the agent's anti-proliferative effects.
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, Guangzhou Road 300, Nanjing 210029, Jiangsu Province, China.
authors.forename: Xinyu
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu Province, China.
authors.forename: Yuxuan
authors.initials: Y
authors.lastname: Fu
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, Guangzhou Road 300, Nanjing 210029, Jiangsu Province, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Tong
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, Guangzhou Road 300, Nanjing 210029, Jiangsu Province, China.
authors.forename: Shuxin
authors.initials: S
authors.lastname: Fan
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, Guangzhou Road 300, Nanjing 210029, Jiangsu Province, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Xu
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, Guangzhou Road 300, Nanjing 210029, Jiangsu Province, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Sun
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, Guangzhou Road 300, Nanjing 210029, Jiangsu Province, China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Liang
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, Guangzhou Road 300, Nanjing 210029, Jiangsu Province, China.
authors.forename: Chuqi
authors.initials: C
authors.lastname: Yan
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, Guangzhou Road 300, Nanjing 210029, Jiangsu Province, China. Electronic address: zhilanyuan@vip.sina.com.
authors.forename: Zhilan
authors.initials: Z
authors.lastname: Yuan
authors.affiliation: Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu Province, China. Electronic address: ybge@njmu.edu.cn.
authors.forename: Yingbin
authors.initials: Y
authors.lastname: Ge
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins / Q000235:genetics / Q000378:metabolism*; D001343:Autophagy / Q000187:drug effects*; D000071186:Beclin-1; D015153:Blotting, Western; D002166:Camptothecin / Q000031:analogs & derivatives* / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival; D002478:Cells, Cultured; D005347:Fibroblasts / Q000378:metabolism / Q000473:pathology*; D005822:Genetic Vectors; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D034741:RNA, Small Interfering / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D058475:Tenon Capsule / Q000378:metabolism / Q000473:pathology*; D014162:Transfection
chemical_list: D051017:Apoptosis Regulatory Proteins; C491997:BECN1 protein, human; D000071186:Beclin-1; C575482:MIRN216 microRNA, human; D008565:Membrane Proteins; D035683:MicroRNAs; D034741:RNA, Small Interfering; C527042:hydroxycamptothecinum; D002166:Camptothecin
keywords: Beclin 1; apoptosis; autophagy; glaucoma; human Tenon's capsule fibroblasts; hydroxycamptothecin; microRNA-216b