Issue Archive

Silk fibroin/collagen composite hydrogels with different matrix stiffness influence the growth and phenotype of human mammary epithelial cells

ZHANG Yi-Ning, JIAO Hui, GUO Li-Na, MA Xin-Yu, GAI Gao-Cheng, ZHANG Jin-Tao, YANG Wen-Qing, WANG Xiu-Li^*

College of Basic Medical Sciences, Dalian Medical University, Dalian 116044, China

Abstract

Extracellular matrix (ECM) stiffness is closely related to the physiological and pathological states of breast tissue. The current study was aimed to investigate the effect of silk fibroin/collagen composite hydrogels with adjustable matrix stiffness on the growth and phenotype of normal breast epithelial cells. In this study, the enzymatic reaction of horseradish peroxidase (HRP) with hydrogen peroxide (H2O2) was used to change the degree of cross-linking of the silk fibroin solution. The rotational rheometer was used to characterize the composite hydrogel’s biomechanical properties. Human normal mammary epithelial cell line MCF-10A were inoculated into composite hydrogels with various stiffness (19.10–4 932.36 Pa) to construct a three dimensional (3D) culture system of mammary epithelial cells. The CCK-8 assay was applied to detect the cell proliferation rate and active states in each group. Hematoxylin-Eosin (HE) staining and whole-mount magenta staining were used for histological evaluation of cell morphology and distribution. The results showed that with the increase of matrix stiffness, MCF-10A cells exhibited inhibited proliferation rate, decreased formation of acinus structures and increased branching structures. Meanwhile, with the increase of matrix stiffness, the polarity of MCF-10A cells was impeded. And the increase of matrix stiffness up-regulated the expression levels of mmp-2, mmp-3, and mmp-9 in MCF-10A cells. Among the genes related to epithelial-mesenchymal transition (EMT), the expression level of the epithelial marker gene E-cadherin was significantly down-regulated, while the interstitial cell marker gene Vimentin was up-regulated, and the expression levels of Snail, Wnt5b and Integrin β1 in the Wnt pathway were up-regulated. These results suggest that the silk fibroin/collagen composite hydrogels with adjustable matrix stiffness regulates the proliferation and the phenotype of MCF-10A cells. The effects of increased matrix stiffness may be closely related to the changes of the polar structures and function of MCF-10A cells, as well as the occurrence of ECM-remodeling and EMT. 

Key words: matrix stiffness; three dimensional culture; microenvironment; epithelial-mesenchymal transition

Received: 　　Accepted:

Corresponding author: 王秀丽　　E-mail: panpan1210@dicp.ac.cn

DOI: 10.13294/j.aps.2022.0043

Citing This Article：

ZHANG Yi-Ning, JIAO Hui, GUO Li-Na, MA Xin-Yu, GAI Gao-Cheng, ZHANG Jin-Tao, YANG Wen-Qing, WANG Xiu-Li. Silk fibroin/collagen composite hydrogels with different matrix stiffness influence the growth and phenotype of human mammary epithelial cells. Acta Physiol Sin 2022; 74 (3): 381-391 (in Chinese with English abstract).