Open AccessNotch4+ cancer stem‐like cells promote the metastatic and invasive ability of melanoma
Author(s) -
Lin Xian,
Sun Baocun,
Zhu Dongwang,
Zhao Xiulan,
Sun Ran,
Zhang Yanhui,
Zhang Danfang,
Dong Xueyi,
Gu Qiang,
Li Yanlei,
Liu Fang
Publication year - 2016
Publication title -
cancer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 1347-9032
DOI - 10.1111/cas.12978
Subject(s) - epithelial–mesenchymal transition , vimentin , cancer research , biology , cancer stem cell , gene knockdown , metastasis , melanoma , cadherin , notch signaling pathway , transfection , stem cell , cancer , cell culture , signal transduction , immunohistochemistry , microbiology and biotechnology , immunology , cell , genetics
Sphere formation in conditioned serum‐free culture medium supplemented with epidermal growth factor and basic fibroblast growth factor (tumorospheres) is considered useful for the enrichment of cancer stem‐like cells, also known as tumor‐initiating cells. We used a gene expression microarray to investigate the gene expression profile of melanoma cancer stem‐like cells ( MCSLC s). The results showed that MCSLC s highly expressed the following Notch signaling pathway molecules: Notch3 ( NM _008716), Notch4 ( NM _010929), Dtx4 ( NM _172442), and JAG 2 ( NM _010588). Immunofluorescence staining showed tumorosphere cells highly expressed Notch4. Notch4 high B16F10 cells were isolated by FACS , and Western blotting showed that high Notch4 expression is related to the expression of epithelial–mesenchymal transition ( EMT )‐associated proteins. Reduced invasive and migratory properties concomitant with the downregulation of the EMT markers Twist1, vimentin, and VE ‐cadherin and the overexpression of E‐cadherin was observed in human melanoma A375 and MUM ‐2B cells. In these cells, Notch4 was also downregulated, both by Notch4 gene knockdown and by application of the γ‐secretase inhibitor, DAPT . Mechanistically, the re‐overexpression of Twist1 by the transfection of cells with a Twist1 expression plasmid led to an increase in VE ‐cadherin expression and a decrease in E‐cadherin expression. Immunohistochemical analysis of 120 human melanoma tissues revealed a significant correlation between the high expression of Notch4 and the metastasis of melanoma. Taken together, our findings indicate that Notch4+ MCSLC s trigger EMT and promote the metastasis of melanoma cells.