title: Telomerase- and angiogenesis-related gene responses to irradiation in human umbilical vein endothelial cells.
abstract: In this study, we investigated the effects of ionizing radiation (IR) on human umbilical vein endothelial cells (HUVECs) in the context of senescence. HUVECs at passage number (PN)1, PN2 and PN3 were exposed to irradiation (2 Gy). The growth rate of the HUVECS was measured by proliferation assay and senescence-associated β-galactosidase assay was used to measure the number of senescent cells. Telomerase activity and the expression of telomerase- and angiogenesis-related genes were measured by telomerase assay and real-time PCR, respectively. The number of senescent cells was significantly increased in the irradiated HUVECs at all PNs. Compared to the controls, telomerase activity, the expression of human telomerase reverse transcriptase (hTERT) and c-Myc in the irradiated HUVECs were downregulated during serial passage. The downregulation of vascular endothelial growth factor (VEGF) was observed in the irradiated HUVECs as the PN increased. The data presented in this study may aid in the understanding of the mechanisms behind IR‑induced EC senescence and telomerase- and angiogenesis‑related gene response.
authors.affiliation: Division of Medical Oncology, Department of Internal Medicine, Yonsei University College of Medicine, Seodaemun‑gu, Seoul 120-752, Republic of Korea.
authors.forename: Hyun
authors.initials: H
authors.lastname: Chang
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Rha
authors.forename: Hei-Cheul
authors.initials: HC
authors.lastname: Jeung
authors.forename: Kyu Hyun
authors.initials: KH
authors.lastname: Park
authors.forename: Tae Soo
authors.initials: TS
authors.lastname: Kim
authors.forename: Yong-Bae
authors.initials: YB
authors.lastname: Kim
authors.forename: Hyun Cheol
authors.initials: HC
authors.lastname: Chung
mesh_terms: D016922:Cellular Senescence / Q000235:genetics / Q000528:radiation effects; D005786:Gene Expression Regulation / Q000528:radiation effects*; D061307:Human Umbilical Vein Endothelial Cells / Q000201:enzymology / Q000378:metabolism* / Q000528:radiation effects*; D006801:Humans; D018919:Neovascularization, Physiologic / Q000235:genetics* / Q000528:radiation effects*; D010641:Phenotype; D011839:Radiation, Ionizing; D019098:Telomerase / Q000378:metabolism*
chemical_list: C509186:TERT protein, human; D019098:Telomerase