Secreted HMGB1 from Wnt activated intestinal cells is required to maintain a crypt progenitor phenotype.
Colorectal cancer (CRC) arises via multiple genetic changes. Mutation of the tumour suppressor gene APC, a key regulator of Wnt signalling, is recognised as a frequent early driving mutation in CRC. We have previously shown that conditional loss of Apc within the murine small intestine (Apcfloxmice) results in acute Wnt signalling activation, altered crypt-villus architecture and many hallmarks of neoplasia. Our transctipomic profiling (Affymetrix Microarrays) and proteomic profiling (iTRAQ-QSTAR) of Apc-deficient intestine inferred the involvement of High Mobility Group Box 1 (Hmgb1) in CRC pathogenesis. Here we assess the contribution of HMGB1 to the crypt progenitor phenotype seen following Apc loss.



Elevated HMGB1 was confirmed in intestinal epithelia and serum following conditional loss of Apc. Treatment of Apcflox mice with anti-HMGB1 neutralising antibody significantly reduced many of the crypt progenitor phenotypes associated with Apc loss; proliferation and apoptosis levels were reduced, cell differentiation was restored and the expansion of stem cell marker expression was eradicated.



Hmgb1 levels in intestinal epithelia and serum in Apcflox and ApcMin mice were assessed using qRT-PCR, Western blot and ELISA assays. The functional importance of elevated extracellular Hmgb1 was assessed using an anti-HMGB1 neutralising antibody in Apcflox mice.



HMGB1 is expressed and secreted from intestinal epithelial cells in response to Wnt signalling activation. This secreted HMGB1 is required to maintain nearly all aspects of the crypt progenitor phenotype observed following Apc loss and add to the body of accumulating evidence indicating that targeting HMGB1 may be a viable novel therapeutic approach.
European Cancer Stem Cell Research Institute, School of Biosciences, Cardiff University, Cardiff, CF24 4HQ, UK.
Karen R
KR
Reed
Infrafrontier GmbH, Neuherberg / München, 85764, Germany.|Institute of Translational Medicine, University of Liverpool, Liverpool, L69 3BX, UK.
Fei
F
Song
European Cancer Stem Cell Research Institute, School of Biosciences, Cardiff University, Cardiff, CF24 4HQ, UK.
Maddy A
MA
Young
European Cancer Stem Cell Research Institute, School of Biosciences, Cardiff University, Cardiff, CF24 4HQ, UK.|Cardiff School of Health Sciences at Cardiff Metropolitan University, Cardiff, CF5 2YB, UK.
Nurudeen
N
Hassan
Institute of Translational Medicine, University of Liverpool, Liverpool, L69 3BX, UK.
Daniel J
DJ
Antoine
European Cancer Stem Cell Research Institute, School of Biosciences, Cardiff University, Cardiff, CF24 4HQ, UK.
Nesibe-Princess B
NB
Gemici
European Cancer Stem Cell Research Institute, School of Biosciences, Cardiff University, Cardiff, CF24 4HQ, UK.
Alan R
AR
Clarke
Institute of Translational Medicine, University of Liverpool, Liverpool, L69 3BX, UK.
John R
JR
Jenkins
D000818:Animals; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D017491:Genes, APC; D024243:HMGB1 Protein / Q000235:genetics / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000378:metabolism*; D007421:Intestine, Small / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D046228:Microarray Analysis; D010641:Phenotype; D055153:Stem Cell Niche; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism; D051153:Wnt Proteins / Q000378:metabolism*; D060449:Wnt Signaling Pathway
D024243:HMGB1 Protein; D051153:Wnt Proteins
Apc; Hmgb1; Wnt signalling; colorectal cancer; intestinal stem cells