Osamu Handa1, Kyousuke Goda2, Yukiko Handa2, Shinya Fukushima2, Motoyasu Osawa2, Takahisa Murao2, Hiroshi Matsumoto2, Eiji Umegaki2, Yoshihiko Fujita3, Kazuto Nishio3, Akiko Shiotani2. 1. Division of Gastroenterology, Department of Internal Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki-City, Okayama, 701-0192, Japan. handao@med.kawasaki-m.ac.jp. 2. Division of Gastroenterology, Department of Internal Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki-City, Okayama, 701-0192, Japan. 3. Department of Medical Oncology, Kindai University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka, 589-8511, Japan.
Abstract
BACKGROUND: Esophageal cancer is a lethal malignancy with a poor prognosis. The incidence of esophageal adenocarcinoma, which develops from Barrett's esophagus (BE), has recently been increasing. In a previous study, we found that PDZK1 expression is higher in long segment BE compared to that in short-segment BE. However, the function of PDZK1 in the mucosa of BE is unclear. AIMS: Clarify the role of PDZK1 in BE mucosa using PDZK1 overexpressed cells. METHODS: Human adenocarcinoma-derived OE33 cells were used as a parental cell line and transfected to generate PDZK1 overexpressed OE33 cells (PC cells) or transfected with empty vector as control cells (NC cells). Cell growth of NC and PC cells in 10% fetal bovine serum was evaluated by cell counting. The effect of PDZK1 on proteasome inhibitor (PSI)-induced apoptosis was qualified by fluorescence microscopy and quantified by flow cytometry. Expression of apoptosis-related proteins was evaluated by western blotting. RESULTS: There were no significant differences in cell growth between NC and PC cells. PSI significantly increased apoptosis in NC cells, but not in PC cells. In response to PSI, increased levels of cleaved-caspase3 and decreased pro-caspase3 levels were found in NC cells, but not in PC cells. In NC cells, PSI significantly decreased Bcl-2 expression without affecting Bax levels. In contrast, high expression of both Bcl-2 and Bax was observed in PC cells. CONCLUSION: Overexpression of PDZK1 protein induces an apoptosis-resistant phenotype in BE cells, which may be a potential therapeutic target.
BACKGROUND: Esophageal cancer is a lethal malignancy with a poor prognosis. The incidence of esophageal adenocarcinoma, which develops from Barrett's esophagus (BE), has recently been increasing. In a previous study, we found that PDZK1 expression is higher in long segment BE compared to that in short-segment BE. However, the function of PDZK1 in the mucosa of BE is unclear. AIMS: Clarify the role of PDZK1 in BE mucosa using PDZK1 overexpressed cells. METHODS: Human adenocarcinoma-derived OE33 cells were used as a parental cell line and transfected to generate PDZK1 overexpressed OE33 cells (PC cells) or transfected with empty vector as control cells (NC cells). Cell growth of NC and PC cells in 10% fetal bovine serum was evaluated by cell counting. The effect of PDZK1 on proteasome inhibitor (PSI)-induced apoptosis was qualified by fluorescence microscopy and quantified by flow cytometry. Expression of apoptosis-related proteins was evaluated by western blotting. RESULTS: There were no significant differences in cell growth between NC and PC cells. PSI significantly increased apoptosis in NC cells, but not in PC cells. In response to PSI, increased levels of cleaved-caspase3 and decreased pro-caspase3 levels were found in NC cells, but not in PC cells. In NC cells, PSI significantly decreased Bcl-2 expression without affecting Bax levels. In contrast, high expression of both Bcl-2 and Bax was observed in PC cells. CONCLUSION: Overexpression of PDZK1 protein induces an apoptosis-resistant phenotype in BE cells, which may be a potential therapeutic target.
Authors: Heiko Pohl; Oliver Pech; Haris Arash; Manfred Stolte; Hendrik Manner; Andrea May; Klaus Kraywinkel; Amnon Sonnenberg; Christian Ell Journal: Gut Date: 2015-06-25 Impact factor: 23.059
Authors: Martin C S Wong; Willie Hamilton; David C Whiteman; Johnny Y Jiang; Youlin Qiao; Franklin D H Fung; Harry H X Wang; Philip W Y Chiu; Enders K W Ng; Justin C Y Wu; Jun Yu; Francis K L Chan; Joseph J Y Sung Journal: Sci Rep Date: 2018-03-14 Impact factor: 4.379