biostudies-literatureUnknown9(28)Kim EJHere, we investigated whether over-activation of AKT pathway is important in the resistance to 5-fluorouracil (5-FU) in SNU-C5/5-FU cells, 5-FU-resistant human colon cancer cells. When compared to wild type SNU-C5 cells (WT), SNU-C5/5-FU cells showed over-activation of PI3K/AKT pathway, like increased phosphorylation of AKT, mTOR, and GSK-3β, nuclear localization of β-catenin, and decreased E-cadherin. Moreover, E-cadherin level was down-regulated in recurrent colon cancer tissues compared to primary colon cancer tissues. Gene silencing of AKT1 or treatment of LY294002 (PI3 kinase inhibitor) increased E-cadherin, whereas decreased phospho-GSK-3β. LY294002 also reduced protein level of β-catenin with no influence on mRNA level. PTEN level was higher in SNU-C5/WT than SNU-C5/5-FU cells, wherOncotarget19911-19928https://www.ebi.ac.uk/biostudies/studies/S-EPMC5929436biostudies-literatureOver-activation of AKT signaling leading to 5-Fluorouracil resistance in SNU-C5/5-FU cells.PMC5929436Kang GJKang HKKim EJKang JIMaeng YHKwon JMBoo HJKoh YSLee CHChang WYYoo ESHyun JWKim YRfalseOver-activation of AKT signaling leading to 5-Fluorouracil resistance in SNU-C5/5-FU cells.Here, we investigated whether over-activation of AKT pathway is important in the resistance to 5-fluorouracil (5-FU) in SNU-C5/5-FU cells, 5-FU-resistant human colon cancer cells. When compared to wild type SNU-C5 cells (WT), SNU-C5/5-FU cells showed over-activation of PI3K/AKT pathway, like increased phosphorylation of AKT, mTOR, and GSK-3β, nuclear localization of β-catenin, and decreased E-cadherin. Moreover, E-cadherin level was down-regulated in recurrent colon cancer tissues compared to primary colon cancer tissues. Gene silencing of AKT1 or treatment of LY294002 (PI3 kinase inhibitor) increased E-cadherin, whereas decreased phospho-GSK-3β. LY294002 also reduced protein level of β-catenin with no influence on mRNA level. PTEN level was higher in SNU-C5/WT than SNU-C5/5-FU cells, wher2018-01-01T00:00:00Z2018 Apr2025-05-18T13:46:43.793Z2025-05-18T13:46:43.793ZS-EPMC59294362973199310.18632/oncotarget.24952