title: Period is involved in the proliferation of human pancreatic MIA-PaCa2 cancer cells by TNF-alpha.
abstract: Recent studies have found alterations to clock genes in several forms of cancer. Period (Per) gene plays an important role in the circadian system, the cell cycle, the induction of apoptosis, and DNA damage. However, the functions of Per in pancreatic cancer have not yet been elucidated. Here, we show that tumor necrosis factor-alpha (TNF-alpha) suppressed the expression of both Per1 and Per3 in MIA-PaCa2 cells, a human pancreatic cancer cell line. The levels of these proteins were 10% lower in the cells treated with 10 ng/mL TNF-alpha. Cell proliferation showed a 15%, 14%, and 16% decrease at 0.4, 2.0, and 10 ng/mL of TNF-alpha, respectively. In MTS-assays, MIA-PaCa2 cells transfected with siRNA against Per1 showed a 19% reduction in proliferation. However, the knockdown of Per3 did not significantly inhibit cell proliferation. The results suggest Per1 to be involved in the inhibition of the proliferation of MIA-PaCa2 cells by TNF-alpha.
authors.affiliation: Department of Pathology and Bioscience, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Suzuki
authors.forename: Fuyuki
authors.initials: F
authors.lastname: Sato
authors.forename: Jun
authors.initials: J
authors.lastname: Kondo
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Tomomi
authors.initials: T
authors.lastname: Kusumi
authors.forename: Katsumi
authors.initials: K
authors.lastname: Fujimoto
authors.forename: Yukio
authors.initials: Y
authors.lastname: Kato
authors.forename: Tatsusuke
authors.initials: T
authors.lastname: Sato
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kijima
mesh_terms: D021441:Carcinoma, Pancreatic Ductal / Q000378:metabolism / Q000473:pathology*; D018797:Cell Cycle Proteins / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000502:physiology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D006801:Humans; D009687:Nuclear Proteins / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000502:physiology*; D010190:Pancreatic Neoplasms / Q000378:metabolism / Q000473:pathology*; D056950:Period Circadian Proteins; D014157:Transcription Factors / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000502:physiology*; D014409:Tumor Necrosis Factor-alpha / Q000502:physiology*
chemical_list: D018797:Cell Cycle Proteins; D009687:Nuclear Proteins; C539022:PER1 protein, human; C512644:PER3 protein, human; D056950:Period Circadian Proteins; D014157:Transcription Factors; D014409:Tumor Necrosis Factor-alpha