Inhibition of SDF-1/CXCR4-induced epithelial–mesenchymal transition by kisspeptin-10

Abstract

Recently we have shown that breast cancer cell invasion was dramatically increased when co-cultured with MG63 cells. In addition we have generated mesenchymal transformed MCF-7 breast cancer cells (MCF-7-EMT), showing significantly increased invasion in contrast to wild type MCF-7 cells (MCF-7 WT). In this study we have analyzed whether stromal derived factor-1 (SDF-1) is responsible for MCF-7 and T-47-D breast cancer cell invasion and epithelial-mesenchymal-transition (EMT). In addition we have analyzed whether kisspeptin-10 (KP-10) treatment affects SDF-1-induced invasion and EMT. Invasion was quantified by assessment of MCF-7 and T-47-D breast cancer cell migration rate through an artificial basement membrane in a modified Boyden chamber during co-culture with MG63 cells or after treatment with SDF-1α, SDF-1β or the combination of both isoforms. Induction of EMT was verified by analysis of protein expression of epithelial marker E-cadherin (CDH1) and mesenchymal markers N-cadherin (CDH2) and Vimentin (VIM). The role of SDF-1 for invasion and induction of EMT in breast cancer cells was analyzed by blocking SDF-1 secretion during co-culture with MG63 cells. In addition effects of KP-10 treatment on SDF-1-induced invasion and EMT were analyzed. Breast cancer cell invasion was significantly increased when co-cultured with MG63 cells. During co-culture SDF-1 protein expression of MG63 cells was significantly induced. The increased breast cancer cell invasion could be blocked by anti-SDF-1 antibodies. Treatment of breast cancer cells in monoculture (without MG63) with SDF-1α, SDF-1β or the combination of both isoforms resulted in a significant escalation of breast cancer cell invasion and induction of EMT. Protein expression of mesenchymal markers CDH2 and VIM was clearly elevated, whereas protein expression of epithelial marker CDH1 was clearly decreased. The SDF-1-induced increase of cell invasion was significantly reduced after treatment with KP-10. In addition, induction of EMT was inhibited. Furthermore, protein expression of the binding site of SDF-1, CXC-motive-chemokine receptor 4 (CXCR-4), was reduced by KP-10. Treatment of MCF-7-EMT cells with KP-10 resulted in a significant drop of cell invasion and CXCR-4 protein expression. Our findings suggest that SDF-1 plays a major role in breast cancer invasion and EMT. SDF-1-induced invasion and EMT can be inhibited by KP-10 treatment by down-regulating CXCR-4 expression.

Cancer-associated fibroblast heterogeneity in axillary lymph nodes drives metastases in breast cancer through complementary mechanisms

“…Although the impact of CAF in metastatic spread has been previously demonstrated [50][51][52][53] , we show here the complementary role of two distinct CAF subpopulations in metastases. We identify a crosstalk between CAF-S1 and cancer cells involving both CXCL12 and TGFβ, consistent with data showing that CAFs secrete CXCL12 and promote cancer cell migration 16,17,[54][55][56][57][58] . In addition, we highlight the role of TGFβ, a well-known EMT inducer 4,59,60 and an important player in fibroblast activation 50,[61][62][63] .…”

Invasion and increased expression of S100A4 and CYR61 in mesenchymal transformed breast cancer cells is downregulated by GnRH

“…showing significantly increased invasion in contrast to wild-type MCF-7 (MCF-7 WT) cells were generated using prolonged mammosphere culture (34,35). Expression of S100A4 mRNA in MCF-7-EMT cells was significantly increased to 165.1±21.0% as compared with MCF-7 WT cells (=100%; P<0.05) ( Fig.…”

The metastasis suppressor gene KISS-1 regulates osteosarcoma apoptosis and autophagy processes

“…In osteosarcoma cells cultured in vitro , the expression of the KISS-1 gene is negatively correlated to the cell proliferation and invasion (6), moreover, after KISS-1 transfection and overexpression, the proliferation and invasion of human osteosarcoma MG-63 and U-2OS cells decline. However, clinical studies have found that the patients with high expression of KISS-1 and GPR54 suffer a higher tumor metastasis rate and mortality (7,8). This study was designed with those findings in mind, we used KISS-1 overexpression vector or siRNA to either highly express or knockdown expression of KISS-1 in the MG-63 osteosarcoma cell line in vitro , in order to analyze the mechanism of proliferation, apoptosis and autophagy of the tumor cells.…”