Open AccessBile acid regulates MUC2 transcription in colon cancer cells via positive EGFR/PKC/Ras/ERK/CREB, PI3K/Akt/IκB/NF-κB and p38/MSK1/CREB pathways and negative JNK/c-Jun/AP-1 pathway
Author(s) -
Hwa Young Lee,
Suzanne C. Crawley,
Ryota Hokari,
Sung Won Kwon,
Young S. Kim
Publication year - 2010
Publication title -
international journal of oncology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.405
H-Index - 122
ISSN - 1019-6439
DOI - 10.3892/ijo_00000573
Subject(s) - creb , protein kinase b , cancer research , mucin , mapk/erk pathway , biology , carcinogenesis , bile acid , pi3k/akt/mtor pathway , transcription factor , microbiology and biotechnology , signal transduction , chemistry , cancer , endocrinology , biochemistry , gene , genetics
MUC2 is a major secretory mucin normally expressed by goblet cells of the intestine, but is aberrantly expressed in colonic neoplasia. Bile acids have been implicated in colorectal carcinogenesis and, therefore, we sought to determine the effects of bile acids on MUC2 expression and regulation in colon cancer cells. Since deoxycholic acid (DCA), a secondary bile acid, has been reported to be a potent mucin secretagogue and tumor promoter, DCA-treated HM3 colon cancer cells were analyzed using promoter-reporter assays of the 5' flanking region of the MUC2 gene. Chemical inhibitors, mutant reporter constructs and EMSA showed that DCA upregulates MUC2 transcription via multiple pathways involving activation of EGFR/PKC/Ras/Raf-1/MEK1/ERK/CREB, PI3/Akt/IkappaB/NF-kappaB and p38/MSK1/CREB while DCA induced MUC2 transcription is inhibited by JNK/c-Jun/AP-1 pathway. These results provide new insight into the complex molecular mechanisms involved in the regulation of mucin gene by bile acids in colon cancer cells that may contribute to further elucidation of colorectal carcinogenesis.