Notch and TNF-α signaling promote cytoplasmic accumulation of OLFM4 in intestinal epithelium cells and exhibit a cell protective role in the inflamed mucosa of IBD patients

Reiko Kuno; Go Ito; Ami Kawamoto; Yui Hiraguri; Hady Yuki Sugihara; Sayaka Takeoka; Sayaka Nagata; Junichi Takahashi; Mao Tsuchiya; Sho Anzai; Tomohiro Mizutani; Hiromichi Shimizu; Shiro Yui; Shigeru Oshima; Kiichiro Tsuchiya; Mamoru Watanabe; Ryuichi Okamoto

doi:10.1016/j.bbrep.2020.100906

Notch and TNF-α signaling promote cytoplasmic accumulation of OLFM4 in intestinal epithelium cells and exhibit a cell protective role in the inflamed mucosa of IBD patients

Biochem Biophys Rep. 2021 Jan 11:25:100906. doi: 10.1016/j.bbrep.2020.100906. eCollection 2021 Mar.

Authors

Reiko Kuno¹, Go Ito², Ami Kawamoto¹, Yui Hiraguri¹, Hady Yuki Sugihara¹, Sayaka Takeoka¹, Sayaka Nagata¹, Junichi Takahashi¹, Mao Tsuchiya¹, Sho Anzai¹, Tomohiro Mizutani¹, Hiromichi Shimizu³, Shiro Yui³, Shigeru Oshima¹, Kiichiro Tsuchiya¹, Mamoru Watanabe², Ryuichi Okamoto^{1

3}

Affiliations

¹ Department of Gastroenterology and Hepatology, Japan.
² Advanced Research Institute, Tokyo Medical and Dental University (TMDU), Tokyo, Japan.
³ Center for Stem Cell and Regenerative Medicine, Tokyo Medical and Dental University (TMDU), Tokyo, Japan.

Abstract

Notch signaling is activated in the intestinal epithelial cells (IECs) of patients with inflammatory bowel disease (IBD), and contributes to mucosal regeneration. Our previous study indicated that TNF-α and Notch signaling may synergistically promote the expression of the intestinal stem cell (ISC) marker OLFM4 in human IECs. In the present study, we investigated the gene regulation and function of OLFM4 in human IEC lines. We confirmed that TNF-α and Notch synergistically upregulate the mRNA expression of OLFM4. Luciferase reporter assay showed that OLFM4 transcription is regulated by the synergy of TNF-α and Notch. At the protein level, synergy between TNF-α and Notch promoted cytoplasmic accumulation of OLFM4, which has potential anti-apoptotic properties in human IECs. Analysis of patient-derived tissues and organoids consistently showed cytoplasmic accumulation of OLFM4 in response to NF-κB and Notch activation. Cytoplasmic accumulation of OLFM4 in human IECs is tightly regulated by Notch and TNF-α in synergy. Such cytoplasmic accumulation of OLFM4 may have a cell-protective role in the inflamed mucosa of patients with IBD.

Keywords: CD, Crohn's disease; ChIP, chromatin immunoprecipitation; DBZ, intestinal epithelial cells; Dox, doxycycline; IBD, inflammatory bowel disease; IEC, dibenzazepine; NICD, Notch intracellular domain; Notch pathway; OLFM4; TNF-α, tumour necrosis factor α; Tumour necrosis factor-α (TNF-α); UC, ulcerative colitis; qRT-PCR, quantitative reverse transcription-polymerase chain reaction analysis.