Inhibition of DNMT suppresses the stemness of colorectal cancer cells through down-regulating Wnt signaling pathway.

Abstract

Cancer stem cell (CSC) theory reveals a new insight into the understanding of tumorigenesis and metastasis. Recently, DNA methylation is suggested to be a potential epigenetic mechanism for maintenance of CSCs. What's more, studies have shown that DNA methyltransferase (DNMT) is essential for CSCs and deletion of DNMT can reduce tumorigenesis by limiting CSC pool. Therefore, targeting the epigenetic modifiers especially DNA methylation offers an optional strategy for treating human cancers. In the present study we found that DNMT inhibitor 5-Aza-2'-deoxycytidine (5-AzaDC) markedly reduced colorectal CSC abundance in vitro and suppressed liver metastatic tumor growth in vivo. And 5-AzaDC inhibited the expression of active β-catenin and down-regulated the Wnt signaling pathway. The Wnt inhibitors were frequently inactivated by promoter methylation in colorectal cancer; however analysis of TCGA data base showed that only the expression of SFRP1 was significantly reduced in tumors compared to normal tissues. In addition, restoring of SFRP1 expression inhibited the stem cell-like potential of colorectal cancer cells. Our results indicated that inhibition of DNMT blocked the self-renewal of colorectal CSCs and SFRP1 was essential for the maintenance of colorectal CSCs.

• Authors: Shanxin Li, Zhipeng Han, Naping Zhao, Bing Zhu, Qianwen Zhang, Xue Yang, Dandan Sheng, Jing Hou, Shiwei Guo, Lixin Wei, Li Zhang
• Journal: Cellular signalling (Cell Signal) Vol. 47 Pg. 79-87 (Jul 2018) ISSN: 1873-3913 [Electronic] England
• PMID: 29601907 (Publication Type: Journal Article)
• Copyright: Copyright © 2018. Published by Elsevier Inc.

Chemical References

• Hyaluronan Receptors
• Intercellular Signaling Peptides and Proteins
• Membrane Proteins
• SFRP1 protein, human
• beta Catenin
• Decitabine
• DNA Modification Methylases

Topics

• Animals
• Cell Line, Tumor
• Cell Proliferation (drug effects)
• Colorectal Neoplasms (drug therapy, metabolism, pathology)
• DNA Methylation (drug effects)
• DNA Modification Methylases (antagonists & inhibitors, metabolism)
• Decitabine (pharmacology, therapeutic use)
• Humans
• Hyaluronan Receptors (metabolism)
• Intercellular Signaling Peptides and Proteins (genetics, metabolism)
• Male
• Membrane Proteins (genetics, metabolism)
• Mice
• Mice, Inbred BALB C
• Neoplastic Stem Cells (cytology, metabolism)
• Survival Rate
• Transplantation, Heterologous
• Wnt Signaling Pathway (drug effects)
• beta Catenin (metabolism)