title: MicroRNA-34a induces a senescence-like change via the down-regulation of SIRT1 and up-regulation of p53 protein in human esophageal squamous cancer cells with a wild-type p53 gene background.
abstract: MiR-34a has been reported as a non-coding RNA universally expressed in normal old cells and a probable suppressor of diverse cancer cells; however, this miRNA's expression and anti-tumor mechanism in esophageal squamous cancer cells (ESCC) remains unclear. We explored these questions in three human ESCC lines, KYSE-450, KYSE-410, and ECa-109, with wild-type p53 and mutant p53 backgrounds. Through a specific stem-loop RT primer for miR-34a, we examined the relevant expression level of miR-34a in these three cell lines using real-time reverse transcription PCR (qRT-PCR). We found that the expression level of miR-34a induced by the DNA damage agent adrmycin (ADR) was both p53- and time-dependent. Following incubation with miR-34a, cellular growth inhibition was exhibited differently in the three cell lines harbored with different p53 backgrounds. Furthermore, the MTT assay demonstrated an miR-34a-related cytotoxic effect in cell growth. Senescence-associated β-galactosidase (SA-β-Gal) staining was used to examine senescence-like phenotypes induced by miR-34a. Mechanistic investigation suggested that the down-regulation of Sirtuin1 (SIRT1) and up-regulation of p53/p21 contributed to the anti-tumor mechanism of miR-34a in wild-type p53 ECa-109 cells, while neither of the apoptosis-related proteins PARP and caspase-3 caused significant changes. In summary, our findings indicated that the intrinsic expression of miR-34a was relatively low and was expressed differently among different p53 backgrounds and ADR treatment times. The anti-tumor effect of miR-34a was primarily dependent on the regulation of SIRT1 and p53/p21 protein, not apoptosis-associated proteins.
authors.affiliation: Department of Radiation Oncology, Zhejiang Province Cancer Hospital, NO. 38 of Guang ji Road, Hangzhou 310022, China.
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Ye
authors.affiliation: Department of Radiation Oncology, Zhejiang Province Cancer Hospital, NO. 38 of Guang ji Road, Hangzhou 310022, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Fang
authors.affiliation: Department of Intense Care Unit, the Second Affiliated Hospital, Zhejiang University School of Medicine, NO. 88 of Jie fang Road, Hangzhou 310009, China.
authors.forename: Shujun
authors.initials: S
authors.lastname: Dai
authors.affiliation: Department of Radiation Oncology, Zhejiang Province Cancer Hospital, NO. 38 of Guang ji Road, Hangzhou 310022, China.
authors.forename: Yuezhen
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Radiation Oncology, Zhejiang Province Cancer Hospital, NO. 38 of Guang ji Road, Hangzhou 310022, China.
authors.forename: Zhenfu
authors.initials: Z
authors.lastname: Fu
authors.affiliation: Department of Radiation Oncology, Zhejiang Province Cancer Hospital, NO. 38 of Guang ji Road, Hangzhou 310022, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Feng
authors.affiliation: Department of Radiation Oncology, the Second Affiliated Hospital, Zhejiang University School of Medicine, NO. 88 of Jie fang Road, Hangzhou 310009, China.
authors.forename: Qichun
authors.initials: Q
authors.lastname: Wei
authors.affiliation: Department of Ultrasonography, the Second Affiliated Hospital, Zhejiang University School of Medicine, NO. 88 of Jie fang Road, Hangzhou 310009, China. Electronic address: huangpintong@126.com.
authors.forename: Pintong
authors.initials: P
authors.lastname: Huang
mesh_terms: D017209:Apoptosis; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D016922:Cellular Senescence; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000502:physiology; D015536:Down-Regulation; D004317:Doxorubicin / Q000494:pharmacology; D004938:Esophageal Neoplasms / Q000235:genetics / Q000473:pathology*; D000077277:Esophageal Squamous Cell Carcinoma; D015972:Gene Expression Regulation, Neoplastic; D016158:Genes, p53 / Q000502:physiology*; D006801:Humans; D035683:MicroRNAs / Q000502:physiology*; D056564:Sirtuin 1 / Q000502:physiology*; D016159:Tumor Suppressor Protein p53 / Q000502:physiology*; D015854:Up-Regulation
chemical_list: C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; C522425:MIRN34 microRNA, human; D035683:MicroRNAs; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D004317:Doxorubicin; C447939:SIRT1 protein, human; D056564:Sirtuin 1
keywords: Esophageal squamous cancer cell; Senescence; miR-34a; p53