title: A critical role for Romo1-derived ROS in cell proliferation.
abstract: Low levels of endogenous reactive oxygen species (ROS) originating from NADPH oxidase have been implicated in various signaling pathways induced by growth factors and mediated by cytokines. However, the main source of ROS is known to be the mitochondria, and increased levels of ROS from the mitochondria have been observed in many cancer cells. Thus far, the mechanism of ROS production in cancer cell proliferation in the mitochondria is not well-understood. We recently identified a novel protein, ROS modulator 1 (Romo1), and reported that increased expression of Romo1-triggered ROS production in the mitochondria. The experiments conducted in the present study showed that Romo1-derived ROS were indispensable for the proliferation of both normal and cancer cells. Furthermore, whilst cell growth was inhibited by blocking the ERK pathway in cells transfected with siRNA directed against Romo1, the cell growth was recovered by addition of exogenous hydrogen peroxide. The results of this study suggest that Romo1-induced ROS may play an important role in redox signaling in cancer cells.
authors.affiliation: Graduate School of Medicine and Brain Korea 21 Program for Biomedical Science, Korea University College of Medicine, Korea University, Seoul 136-705, Republic of Korea.
authors.forename: Ah Ram
authors.initials: AR
authors.lastname: Na
authors.forename: Young Min
authors.initials: YM
authors.lastname: Chung
authors.forename: Seung Baek
authors.initials: SB
authors.lastname: Lee
authors.forename: Seon Ho
authors.initials: SH
authors.lastname: Park
authors.forename: Myeong-Sok
authors.initials: MS
authors.lastname: Lee
authors.forename: Young Do
authors.initials: YD
authors.lastname: Yoo
mesh_terms: D045744:Cell Line, Tumor; D049109:Cell Proliferation; D006367:HeLa Cells; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism*; D009369:Neoplasms / Q000378:metabolism* / Q000473:pathology*; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D008565:Membrane Proteins; D024101:Mitochondrial Proteins; C513338:ROMO1 protein, human; D017382:Reactive Oxygen Species