Identification and differentiation of breast cancer stem cells under tumor microenvironment

Zhang Shu-qing; Zhang Bo; Hong Liang; Zhou Yong-an; Zhao Liang

doi:10.3969/j.issn.2095-4344.2015.14.005

Abstract：BACKGROUND:Breast cancer stem cel s have a greater impact on the occurrence and metastasis of breast cancer. Under simulated tumor microenvironment, we can better analyze the proliferation and differentiation of breast cancer stem cel s. OBJECTIVE:To explore the tumor microenvironment effect on the differentiation of breast cancer stem cel s. METHODS:Breast cancer cel s and MCF-7 cel s were primarily cultured in fibroblast supernatant and serum-free PCM-2 medium, and formation of breast cancer cel s microspheres was observed. Proliferative ability of breast cancer cel s was detected using MTT colorimetry, and the surface markers of breast cancer stem cel s and epithelial-mesenchymal transition markers were measured using immunocytochemistry and RT-PCR methods. RESULTS AND CONCLUSION:The diameter of primary cel microspheres was larger in the serum-free PCM-2 medium than in the fibroblast supernatant, but the culture speed was faster in the fibroblast supernatant than the serum-free PCM-2 medium. At 3 days of primary culture, the expression of ALDH1 in primary cel s was greatly higher in the serum-free PCM-2 medium than in the fibroblast supernatant. However, the expressions of E-cadherin and vimentin were up-regulated in the fibroblast supernatant than in the serum-free PCM-2 medium. In addition, the expressions of E-cadherin and vimentin in MCF-7 cel s cultured in the fibroblast supernatant were up-regulated, while the expressions of ALDH1 and Oct-4 were downregulated. These findings indicate that the tumor environment has some certain effects on the growth and differentiation of breast cancer stem cel s, and some cytokines secreted from fibroblast supernatant can promote the proliferation and differentiation of breast cancer stem cel microspheres to some extent.