Endoglin Expression on Cancer-Associated Fibroblasts Regulates Invasion and Stimulates Colorectal Cancer Metastasis.

Abstract

PURPOSE:

Cancer-associated fibroblasts (CAF) are a major component of the colorectal cancer tumor microenvironment. CAFs play an important role in tumor progression and metastasis, partly through TGF-β signaling pathway. We investigated whether the TGF-β family coreceptor endoglin is involved in CAF-mediated invasion and metastasis.

EXPERIMENTAL DESIGN:

CAF-specific endoglin expression was studied in colorectal cancer resection specimens using IHC and related to metastases-free survival. Endoglin-mediated invasion was assessed in vitro by transwell invasion, using primary colorectal cancer-derived CAFs. Effects of CAF-specific endoglin expression on tumor cell invasion were investigated in a colorectal cancer zebrafish model, whereas liver metastases were assessed in a mouse model.

RESULTS:

CAFs specifically at invasive borders of colorectal cancer express endoglin and increased expression intensity correlated with increased disease stage. Endoglin-expressing CAFs were also detected in lymph node and liver metastases, suggesting a role in colorectal cancer metastasis formation. In stage II colorectal cancer, CAF-specific endoglin expression at invasive borders correlated with poor metastasis-free survival. In vitro experiments revealed that endoglin is indispensable for bone morphogenetic protein (BMP)-9-induced signaling and CAF survival. Targeting endoglin using the neutralizing antibody TRC105 inhibited CAF invasion in vitro. In zebrafish, endoglin-expressing fibroblasts enhanced colorectal tumor cell infiltration into the liver and decreased survival. Finally, CAF-specific endoglin targeting with TRC105 decreased metastatic spread of colorectal cancer cells to the mouse liver.

CONCLUSIONS:

Endoglin-expressing CAFs contribute to colorectal cancer progression and metastasis. TRC105 treatment inhibits CAF invasion and tumor metastasis, indicating an additional target beyond the angiogenic endothelium, possibly contributing to beneficial effects reported during clinical evaluations.See related commentary by Becker and LeBleu, p. 6110.

• Authors: Madelon Paauwe, Mark J A Schoonderwoerd, Roxan F C P Helderman, Tom J Harryvan, Arwin Groenewoud, Gabi W van Pelt, Rosalie Bor, Danielle M Hemmer, Henri H Versteeg, B Ewa Snaar-Jagalska, Charles P Theuer, James C H Hardwick, Cornelis F M Sier, Peter Ten Dijke, Lukas J A C Hawinkels
• Journal: Clinical cancer research : an official journal of the American Association for Cancer Research (Clin Cancer Res) Vol. 24 Issue 24 Pg. 6331-6344 (12 15 2018) ISSN: 1557-3265 [Electronic] United States
• PMID: 29945992 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: ©2018 American Association for Cancer Research.

Chemical References

• Biomarkers
• Endoglin
• Ligands
• Transforming Growth Factor beta

Topics

• Animals
• Biomarkers
• Cancer-Associated Fibroblasts (metabolism, pathology)
• Cell Line, Tumor
• Cell Movement
• Cell Survival (genetics)
• Colorectal Neoplasms (genetics, metabolism, mortality, pathology)
• Disease Models, Animal
• Endoglin (genetics, metabolism)
• Fibroblasts (metabolism)
• Fluorescent Antibody Technique
• Gene Expression Regulation, Neoplastic
• Humans
• Immunohistochemistry
• Ligands
• Male
• Mice
• Neoplasm Metastasis
• Neoplasm Staging
• Prognosis
• Signal Transduction
• Transforming Growth Factor beta (metabolism)
• Tumor Microenvironment (genetics)
• Zebrafish