TY - JOUR
T1 - Prohibitin attenuates colitis-associated tumorigenesis in mice by modulating p53 and STAT3 apoptotic responses
AU - Kathiria, Arwa S.
AU - Neumann, William L.
AU - Rhees, Jennifer
AU - Hotchkiss, Erin
AU - Cheng, Yulan
AU - Genta, Robert M.
AU - Meltzer, Stephen J.
AU - Souza, Rhonda F.
AU - Theiss, Arianne L.
PY - 2012/11/15
Y1 - 2012/11/15
N2 - Although inflammatory bowel disease is associated with higher risk of colorectal cancer, the precise pathogenic mechanisms underlying this association are not completely understood. Prohibitin 1 (PHB), a protein implicated in the regulation of proliferation, apoptosis, and transcription, is decreased in intestinal inflammation. In this study, we have established a key function for PHB in mediating colitis-associated cancer. Wild-type and transgenic (Tg) mice specifically overexpressing PHB in intestinal epithelial cells were subjected to a classical two-stage protocol of colitis-associated carcinogenesis. In addition, wild-type and p53 null human cell models were used to assess PHB interaction with STAT3 and p53. Wild-type mice exhibited decreased mucosal PHB protein expression during colitis-associated carcinogenesis. Tg mice exhibited decreased susceptibility in a manner associated with increased apoptosis, p53, Bax, and Bad expression plus decreased Bcl-xL and Bcl-2 expression. PHB overexpression in wild-type but not p53 null human cells increased expression of Bax, Bad, and caspase-3 cleavage. In wild-type p53 cells, PHB overexpression decreased basal and interleukin-6-induced STAT3 activation and expression of the STAT3 responsive genes Bcl-xL and Bcl-2. PHB coimmunoprecipitated with phospho-STAT3 in addition to p53 in cultured cell lysates and colon mucosa. This is the first study to show interaction between PHB and STAT3 in vivo. In summary, our findings suggest that PHB protects against colitisassociated cancer by modulating p53- and STAT3-mediated apoptosis. Modulation of PHB expression in intestinal epithelial cells may offer a potential therapeutic approach to prevent colitis-associated carcinogenesis.
AB - Although inflammatory bowel disease is associated with higher risk of colorectal cancer, the precise pathogenic mechanisms underlying this association are not completely understood. Prohibitin 1 (PHB), a protein implicated in the regulation of proliferation, apoptosis, and transcription, is decreased in intestinal inflammation. In this study, we have established a key function for PHB in mediating colitis-associated cancer. Wild-type and transgenic (Tg) mice specifically overexpressing PHB in intestinal epithelial cells were subjected to a classical two-stage protocol of colitis-associated carcinogenesis. In addition, wild-type and p53 null human cell models were used to assess PHB interaction with STAT3 and p53. Wild-type mice exhibited decreased mucosal PHB protein expression during colitis-associated carcinogenesis. Tg mice exhibited decreased susceptibility in a manner associated with increased apoptosis, p53, Bax, and Bad expression plus decreased Bcl-xL and Bcl-2 expression. PHB overexpression in wild-type but not p53 null human cells increased expression of Bax, Bad, and caspase-3 cleavage. In wild-type p53 cells, PHB overexpression decreased basal and interleukin-6-induced STAT3 activation and expression of the STAT3 responsive genes Bcl-xL and Bcl-2. PHB coimmunoprecipitated with phospho-STAT3 in addition to p53 in cultured cell lysates and colon mucosa. This is the first study to show interaction between PHB and STAT3 in vivo. In summary, our findings suggest that PHB protects against colitisassociated cancer by modulating p53- and STAT3-mediated apoptosis. Modulation of PHB expression in intestinal epithelial cells may offer a potential therapeutic approach to prevent colitis-associated carcinogenesis.
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U2 - 10.1158/0008-5472.CAN-12-0603
DO - 10.1158/0008-5472.CAN-12-0603
M3 - Article
C2 - 22869582
AN - SCOPUS:84869224215
VL - 72
SP - 5778
EP - 5789
JO - Cancer Research
JF - Cancer Research
SN - 0008-5472
IS - 22
ER -