Notch inhibits expression of the Krüppel-like factor 4 tumor suppressor in the intestinal epithelium

The zinc finger-containing transcription factor, Krüppel-like factor 4 (KLF4), inhibits cell proliferation. An in vivo tumor-suppressive role for KLF4 is shown by the recent finding that Klf4 haploinsufficiency in Apc(Min/+) mice promotes intestinal tumorigenesis. Studies also show that KLF4 is required for the terminal differentiation of goblet cells in the mouse intestine. The Notch signaling pathway suppresses goblet cell formation and is up-regulated in intestinal tumors. Here, we investigated the relationship between Notch signaling and KLF4 expression in intestinal epithelial cells. The rate of proliferation of HT29 human colon cancer cells was reduced when treated with the gamma-secretase inhibitor dibenzazepine to inhibit Notch signaling or small interfering RNA directed against Notch. KLF4 levels were increased in dibenzazepine-treated or Notch small interfering RNA-treated cells. Conversely, overexpression of Notch in HT29 cells reduced KLF4 levels, suppressed KLF4 promoter activity, and increased proliferation rate. Treatment of Apc(Min/+) mice with dibenzazepine resulted in a 50% reduction in the number of intestinal adenomas compared with the vehicle-treated group (P < 0.001). Both the normal-appearing intestinal mucosa and adenomas obtained from dibenzazepine-treated Apc(Min/+) mice had increased goblet cell numbers and Klf4 staining accompanied by reduced cyclin D1 and Ki-67 staining when compared with those from vehicle-treated mice. Results of these studies indicate that Notch signaling suppresses KLF4 expression in intestinal tumors and colorectal cancer cells. Inhibition of Notch signaling increases KLF4 expression and goblet cell differentiation and reduces proliferation and tumor formation. KLF4 is therefore a potential mediator for the antitumor effect of Notch inhibitors such as dibenzazepine.

Medienart:

E-Artikel

Erscheinungsjahr:

2008

Erschienen:

2008

Enthalten in:

Zur Gesamtaufnahme - volume:6

Enthalten in:

Molecular cancer research : MCR - 6(2008), 12 vom: 01. Dez., Seite 1920-7

Sprache:

Englisch

Beteiligte Personen:

Ghaleb, Amr M [VerfasserIn]
Aggarwal, Gaurav [VerfasserIn]
Bialkowska, Agnieszka B [VerfasserIn]
Nandan, Mandayam O [VerfasserIn]
Yang, Vincent W [VerfasserIn]

Links:

Volltext

Themen:

Adenomatous Polyposis Coli Protein
Dibenzazepine
Dibenzazepines
J411KQJ8C2
Journal Article
KLF4 protein, human
Klf4 protein, mouse
Kruppel-Like Factor 4
Kruppel-Like Transcription Factors
NOTCH1 protein, human
Receptor, Notch1
Research Support, N.I.H., Extramural

Anmerkungen:

Date Completed 02.02.2009

Date Revised 03.12.2021

published: Print

Citation Status MEDLINE

doi:

10.1158/1541-7786.MCR-08-0224

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM185103685