Abstract
Background/Aim: Epidermal growth factor receptor (EGFR) has been suggested to play an important role in survival, proliferation, migration, differentiation, and tumorigenesis of many cell types. Breast cancer patients with high EGFR expression have a poor prognosis. In this study, we investigated the molecular mechanism of the inhibitory effect of isochlorogenic acid c (ICAC) extracted from Lonicera japonica on elevated EGFR levels of the triple-negative breast cancer (TNBC) cell line, MDA-MB-231. Materials and Methods: The cell viability and cell-cycle analysis were evaluated using 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay and flow cytometry, respectively. The migration ability and invasiveness of ICAC-treated MDA-MB-231 were examined by migration and Matrigel invasion assay. The epithelial-mesenchymal-transition (EMT)-related protein expression was examined by western blotting and reverse transcriptase-polymerase chain reaction (RT-PCR). Results: ICAC led to significant morphological changes and suppressed migration and invasion capacities of highly metastatic MDA-MB-231 cells. Western blot analysis for EGFR/EMT-associated proteins suggested that ICAC attenuated the mesenchymal traits as observed by up-regulation of epithelial markers and down-regulation of mesenchymal markers as well as decreased activities of matrix metalloproteinase-9 (MMP-9). Conclusion: These results suggested that the inhibitory effects of ICAC against EGFR-induced EMT and MDA-MB-231 cell invasion were dependent on the EGFR/ phospholipase Cγ (PLCγ)/extracellular regulated protein kinase ½ (ERK½)/slug signaling pathway. Therefore, the obtained results could provide us clues for the next therapeutic strategy in the treatment of TNBC.
- Isochlorogenic acid c (ICAC)
- epithelial–mesenchymal transition (EMT)
- epidermal growth factor receptor (EGFR)
- triple-negative breast cancer (TNBC)
- MDA-MB-231 cells
- Received January 5, 2018.
- Revision received February 15, 2018.
- Accepted February 16, 2018.
- Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved