Title:Comparative Proteomic Analysis of Colon Cancer Cell HCT-15 in Response to All-Trans Retinoic Acid Treatment
VOLUME: 19 ISSUE: 12
Author(s):Jie Zhao, Gaotian Wen, Ming Ding, Jian-Yi Pan, Mei-Lan Yu, Fukun Zhao, Xia-Lian Weng and Jiang-Li Du
Affiliation:College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, People’s Republic of China.
Keywords:All-trans retinoic acid, colon cancer, 2-DE, HCT-15 cell, mass spectrometry, proteomics, biological mechanisms, cell proliferation, gene expression, gene transcription.
Abstract:Colon cancer is one of the most common malignances. In vitro and in vivo study show that retinoic acids inhibit
a wide variety of cancer cells but the molecular mechanism of their anti-tumor effects are not yet fully understood. Alltrans
retinoic acid (ATRA), an isomer of retinoic acid, can inhibit the proliferation of HCT-15 human colon cancer cell
line. A proteomic analysis was performed using HCT-15 treated with ATRA to further elucidate the retinoic acid signaling
pathway and its anti-tumor effect mechanism. MTT results showed that the growth of HCT-15 cells were significantly
inhibited by ATRA. The alkaline phosphatase activity assay showed that ATRA failed to induce the differentiation of
HCT-15. The DNA ladder detection showed that ATRA induced apoptosis in HCT-15. Two-dimensional gel electrophoresis
coupled with MALDI-TOF/TOF mass spectrometry identified 13 differentially expressed proteins in HCT-15 cells
after all-trans retinoic acid treatment. Among the identified differentially expressed proteins, there were four scaffold proteins
(YWHAE, SFN, YWHAB, and YWHAZ), two ubiquitin modification related proteins (ISG-15 and UBE2N), two
translational initiation factors (EIF1AX and EIF3K), two cytoskeleton related proteins (EZRI and CNN3), two proteinmodification
related proteins (TXNDC17 and PIMT), and one enzyme related to phospholipid metabolism (PSP). Both
EZRI and UBE2N were rendered to western-blot validation and the results were consistent with the two-dimension electrophoresis
analysis. In this study, the differentially expressed proteins in HCT-15 treated by ATRA were identified,
which will assist the further elucidation of the anti-tumor mechanism of retinoic acids.
