RT Journal Article
SR Electronic
T1 Mitosis-Independent <em>Survivin</em> Gene Expression <em>In vivo</em> and Regulation by p53
JF Cancer Research
JO Cancer Res
FD American Association for Cancer Research
SP 3392
OP 3395
DO 10.1158/0008-5472.CAN-05-4537
VO 66
IS 7
A1 Xia, Fang
A1 Altieri, Dario C.
YR 2006
UL http://cancerres.aacrjournals.org/content/66/7/3392.abstract
AB Survivin is an essential mitotic gene, and this has been speculated to reflect its primary function in development and cancer. Here, we generated a knock-in transgenic mouse (SVVp-GFP) in which a green fluorescent protein (GFP) reporter gene was placed under the control of the survivin promoter that regulates transcription at mitosis. The expression of endogenous survivin was widespread in mouse tissues during development and shortly after birth. In contrast, GFP reactivity was undetectable in transgenic mouse embryos, and was largely limited postnatally to mitotic cells in the testes. Double transgenic mice generated in the tumor-prone Min/+ background exhibited intestinal adenomas that strongly expressed endogenous survivin, but only isolated GFP-positive cells. Conversely, dysplastic adenomas (16%) stained intensely for GFP, and revealed focal reactivity for mutant, but not wild-type, p53. The expression of GFP was increased by ∼10-fold in p53−/− as opposed to p53+/+ HCT116 colorectal cancer cells, and reintroduction of p53 in p53−/− cells abolished GFP expression. Therefore, the mitotic transcription of the survivin gene is highly restricted in vivo, and unexpectedly negatively regulated by p53. Contrary to a commonly held view, the dominant function(s) of survivin in development and tumor ontogeny are largely cell cycle–independent. (Cancer Res 2006; (66)7: 3392-5) ©2006 American Association for Cancer Research.