Identification of CEA-interacting proteins in colon cancer cells and their changes in expression after irradiation
Radiation Oncology Journal
; : 281-288, 2017.
Article
in En
| WPRIM
| ID: wpr-144698
Responsible library:
WPRO
ABSTRACT
PURPOSE:
The serum carcinoembryonic antigen (CEA) level has been recognized as a prognostic factor in colorectal cancer, and associated with response of rectal cancer to radiotherapy. This study aimed to identify CEA-interacting proteins in colon cancer cells and observe post-irradiation changes in their expression. MATERIALS ANDMETHODS:
CEA expression in colon cancer cells was examined by Western blot analysis. Using an anti-CEA antibody or IgG as a negative control, immunoprecipitation was performed in colon cancer cell lysates. CEA and IgG immunoprecipitates were used for liquid chromatography–tandem mass spectrometry (LC-MS/MS) analysis. Proteins identified in the CEA immunoprecipitates but not in the IgG immunoprecipitates were selected as CEA-interacting proteins. After radiation treatment, changes in expression of CEA-interacting proteins were monitored by Western blot analysis.RESULTS:
CEA expression was higher in SNU-81 cells compared with LoVo cells. The membrane localization of CEA limited the immunoprecipitation results and thus the number of CEA-interacting proteins identified. Only the Ras-related protein Rab-6B and lysozyme C were identified as CEA-interacting proteins in LoVo and SNU-81 cells, respectively. Lysozyme C was detected only in SNU-81, and CEA expression was differently regulated in two cell lines; it was down-regulated in LoVo but up-regulated in SNU-81 in radiation dosage-dependent manner.CONCLUSION:
CEA-mediated radiation response appears to vary, depending on the characteristics of individual cancer cells. The lysozyme C and Rab subfamily proteins may play a role in the link between CEA and tumor response to radiation, although further studies are needed to clarify functional roles of the identified proteins.Key words
Full text:
1
Index:
WPRIM
Main subject:
Radiotherapy
/
Rectal Neoplasms
/
Mass Spectrometry
/
Immunoglobulin G
/
Colorectal Neoplasms
/
Carcinoembryonic Antigen
/
Muramidase
/
Cell Line
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Blotting, Western
/
Colon
Type of study:
Diagnostic_studies
/
Prognostic_studies
Language:
En
Journal:
Radiation Oncology Journal
Year:
2017
Type:
Article