title: Malignant progression in O6-methylguanine-DNA methyltransferase-deficient esophageal cancer cells is associated with Ezrin protein.
abstract: The abnormal function of O(6)-methylguanine-DNA methyltransferase (MGMT) is reported to be associated with the occurrence of various tumors and malignant tumor progression. However, little evidence is available to describe its role in esophageal carcinogenesis. To address this issue, we constructed a stable MGMT-silenced esophageal cancer cell line by RNA interference, and exposed the cells to N-methyl-N-nitro-N-nitrosoguanidine (MNNG) to investigate the role that MGMT plays in toxicity. During this time, we also observed the malignant behavior of cells in vitro and in vivo. In addition, two-dimensional electrophoresis and mass spectrometry were used to detect and confirm the proteins that were differentially expressed in the MGMT-deficient and MGMT-proficient cells, which might be responsible for the malignant alteration of cells. Results showed that the IC(50) of MGMT-deficient and MGMT-proficient cells exposed to MNNG was 30 μM and 65 μM, respectively, and MGMT-deficient cells had more aggressive motility and invasive abilities compared with MGMT-proficient cells. Nineteen differentially expressed proteins were detected between the MGMT-deficient and MGMT-proficient cells, 14 of which were identified, including the membrane-cytoskeleton linker protein, Ezrin, which was confirmed by both mass spectrometry and western blot analysis. The correlation between MGMT, Ezrin expression, and the malignant behavior of one normal epithelial esophageal cell line and seven esophageal cancer lines is discussed. In conclusion, loss of MGMT expression leads EC109 esophageal cancer cells to have increased malignant behavior, which may correlate with its high Ezrin protein expression.
authors.affiliation: Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China.
authors.forename: Yaoyao
authors.initials: Y
authors.lastname: Su
authors.forename: Ran
authors.initials: R
authors.lastname: Liu
authors.forename: JingYi
authors.initials: J
authors.lastname: Sheng
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.forename: Enchun
authors.initials: E
authors.lastname: Pan
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.forename: Yuepu
authors.initials: Y
authors.lastname: Pu
authors.forename: Juan
authors.initials: J
authors.lastname: Zhang
authors.forename: Geyu
authors.initials: G
authors.lastname: Liang
authors.forename: Derong
authors.initials: D
authors.lastname: Tang
authors.forename: Lihong
authors.initials: L
authors.lastname: Yin
mesh_terms: D000818:Animals; D015153:Blotting, Western; D016466:CHO Cells; D002448:Cell Adhesion; D002465:Cell Movement; D049109:Cell Proliferation; D006224:Cricetinae; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D004938:Esophageal Neoplasms / Q000378:metabolism* / Q000473:pathology*; D004947:Esophagus / Q000378:metabolism / Q000473:pathology; D005455:Fluorescent Antibody Technique; D006147:Guanine / Q000031:analogs & derivatives / Q000378:metabolism; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009154:Mutation / Q000235:genetics; D019853:O(6)-Methylguanine-DNA Methyltransferase / Q000037:antagonists & inhibitors / Q000172:deficiency* / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014162:Transfection; D000099149:Ezrin
chemical_list: D003598:Cytoskeletal Proteins; D006147:Guanine; D019853:O(6)-Methylguanine-DNA Methyltransferase; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D000099149:Ezrin; C008449:O-(6)-methylguanine