ABSTRACT
CD44, as a superficial cellular glycoprotein, is an essential factor in cell-cell and cell-matrix interaction. The CD44 expression level has been substantially up-regulated in breast cancer, and this upregulation facilitates tumor proliferation and angiogenesis. This study aims to evaluate the combination therapy of Jet Pei/CD44-specific-siRNA/doxorubicin in breast cancer MDA-MB468 cell line. The MTT assay, wound healing test, colony formation assay, DAPI staining, and flow cytometry were performed to investigate the tumoral cell viability, migration, clonogenesis, and apoptosis progression. The quantitative real-time PCR (qRT-PCR) was performed to demonstrate the CD44 expression level. Finally, the effect of CD44 silencing on the expression of VEGF, CXCR4, MMP9, and MiR-142-3p was measured. The combination of CD44-specific-siRNA with doxorubicin decreased tumoral metastasis, proliferation, invasion, and migration, and increased apoptosis in MDA-MB468 cells. In conclusions, CD44 can serve as a therapeutic target in breast cancer. Moreover, the combination therapy of CD44-specific-siRNA with doxorubicin can be a promising treatment for patients with breast cancer.
Subject(s)
Antibiotics, Antineoplastic/pharmacology , Apoptosis/drug effects , Doxorubicin/pharmacology , Gene Expression Regulation, Neoplastic , Hyaluronan Receptors/antagonists & inhibitors , RNA, Messenger/antagonists & inhibitors , Transfection/methods , Apoptosis/genetics , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , Female , Humans , Hyaluronan Receptors/genetics , Hyaluronan Receptors/metabolism , MCF-7 Cells , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase 9/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Polyethyleneimine/chemistry , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Receptors, CXCR4/genetics , Receptors, CXCR4/metabolism , Signal Transduction , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolismABSTRACT
AIMS: The extracellular matrix (ECM) within the tumor nest plays a key role in cancer cell proliferation and invasion. It has been proven that the increased density of ECM, especially collagen network, correlates with the poor distribution of gold-nanoparticles (GNPs) to the tumor mass. Here, for the first time, we examined the combined effect of collagenase (COL) with metformin (MET)-conjugated GNPs on mammosphere generated from JIMT-1 breast cell line in vitro. MAIN METHODS: Mammospheres (on days 7 and 14) and monolayer culture were treated with MET, MET-GNPs, and a mixture of COL-GNPs and MET-GNPs for 5â¯days. To assess the impacts of the engineered nanoparticles (NPs) on the survival/apoptosis of cancer cells and cancer stem cells (CSCs), the amount/activity of collagen and the expression of pyruvate kinase M2, different methods were applied, including MTT, flow cytometry, immunofluorescence, ELISA and real-time PCR analyses. Our results confirmed the enhanced cytotoxic effects of MET-GNPs combined with COL-GNPs on mammospheres compared to the cells treated with MET alone or MET-GNPs. KEY FINDINGS: Upon treatment with the mixture of MET-GNPs and COL-GNPs, the population of the apoptotic cells was significantly increased. A marked reduction was found in the number of CD24-/CD44+ CSCs and the amount of collagen in the group received a mixture of MET-GNPs and COL-GNPs. SIGNIFICANCE: Based on our findings, the use of COL can improve the cellular interaction/penetration of MET-GNPs in mammospheres and its antitumor impacts on the CSCs.
