Project description:Human mesenchymal stem cell (MSC)-conditioned medium (CM) was previously reported to affect the biology of tumor cells; however, the precise mechanisms remain unclear. Here, we show that MSCs secreted 40- to 100-nm particles, which have the typical characteristics of exosomes, and these MSC-derived exosomes promoted migration of the breast cancer cell line MCF7. To further investigate the effect of MSC-exosomes on MCF7, we analyzed the gene expression profiles of MCF7 treated with or without MSC-exosomes for 24 h. Investigation of whole genome gene expression level changes in breast cancer cell line MCF7 which were treated with or without mesenchymal stem cell-derived exosomes. This study uses total RNA recovered from two samples. One sample is MCF7 treated with PBS for 24 hours and another one is MCF7 treated with mesenchymal stem cell-derived exosomes for 24hours. The ultimate concentration of mesenchymal stem cell-derived exosomes used in this experiment was 400ng/ul.
Project description:Human mesenchymal stem cell (MSC)-conditioned medium (CM) was previously reported to affect the biology of tumor cells; however, the precise mechanisms remain unclear. Here, we show that MSCs secreted 40- to 100-nm particles, which have the typical characteristics of exosomes, and these MSC-derived exosomes promoted migration of the breast cancer cell line MCF7. To further investigate the effect of MSC-exosomes on MCF7, we analyzed the gene expression profiles of MCF7 treated with or without MSC-exosomes for 24 h.
Project description:We hypothesized that miRNAs in the bone maroow mesenchymal stem cells (BM-MSC)-derived exosomes contributed to the phenotype change of breast cancer cells through exosome transfer. We analyzed the miRNA expression signature in BM-MSC-derived exosomes. We compared the miRNA expression levels in exosomes between BM-MSCs and adult fibroblasts (as a control). In this study, miRNA expression including in bone-marrow mesenchymal cell (BM-MSC)-derived exosomes was examined, and compared with that of exosomes derived from adult fibroblast cells or the BM-MSC cells. In addition, miRNA expression of BM-MSC exosomes was also compared with that of breast cancer cells with or without cancer stem cell marker.
Project description:Introduction: Mesenchymal stem cells (MSCs) are commonly known to influence the progression of cancer due to their ability to migrate to the tumor microenvironment and interact with cancer cells. Exosomes have been found secreted by most cell types and have been shown to act as cargo carrying biomolecules including microRNA (miRNAs). Thus, understanding interaction between MSCs and cancer cells via exosomal miRNAs is crucial in determining the therapeutic role of MSC in treating breast cancer cells and relapse. Methods: Exosomes were harvested from the medium of indirect co-culture of MCF7-luminal and MDA-MB-231-basal breast cancer cells (BCCs) subtypes with adipose MSCs and profiled for miRNAs using next-generation sequencing. Results: The interaction resulted in the changes of exosomal miRNAs profiles that modulate essential signalling pathways and cell cycle arrest into dormancy via inhibition of epithelial-to-mesenchymal transition (EMT). The maintenance and induction of epithelial features in MCF7 and MDA cells have led to a positive correlation with the reduction of proliferation and metastasis as well as increased drug resistance. Overall, adipose MSCs mediated delivery of consensus miRNAs particularly miR-200 family in MCF7, miR-146a in MDA and miR-941 in both BCCs subtypes via exosomes.
Project description:Background: Docosahexaenoic acid (DHA) is a natural compound with anticancer and anti-angiogenesis activity that is currently under investigation as both a preventative agent and an adjuvant to breast cancer therapy. However, the precise mechanisms of DHA’s anticancer activities are unclear. It is understood that the intercommunication between cancer cells and their microenvironment is essential to tumor angiogenesis. Exosomes are extracellular vesicles that are important mediators of intercellular communication and play a role in promoting angiogenesis. However, very little is known about the contribution of breast cancer exosomes to tumor angiogenesis or whether exosomes can mediate DHA’s anticancer action. Results: Exosomes were collected from MCF7 and MDA-MB-231 breast cancer cells after treatment with DHA. We observed an increase in exosome secretion and exosome microRNA contents from the DHA-treated cells. The expression of 83 microRNAs in the MCF7 exosomes was altered by DHA (>2-fold). The most abundant exosome microRNAs (let-7a, miR-23b, miR-27a/b, miR-21, let-7, and miR-320b) are known to have anti-cancer and/or anti-angiogenic activity. These microRNAs were also increased by DHA treatment in the exosomes from other breast cancer lines (MDA-MB-231, ZR751 and BT20), but not in exosomes from normal breast cells (MCF10A). When DHA-treated MCF7 cells were co-cultured with or their exosomes were directly applied to endothelial cell cultures, we observed an increase in the expression of these microRNAs in the endothelial cells. Furthermore, overexpression of miR-23b and miR-320b in endothelial cells decreased the expression of their pro-angiogenic target genes (PLAU, AMOTL1, NRP1 and ETS2) and significantly inhibited tube formation by endothelial cells, suggesting that the microRNAs transferred by exosomes mediate DHA’s anti-angiogenic action. These effects could be reversed by knockdown of the Rab GTPase, Rab27A, which controls exosome release. Conclusions: We conclude that DHA alters breast cancer exosome secretion and microRNA contents, which leads to the inhibition of angiogenesis. Our data demonstrate that breast cancer exosome signaling can be targeted to inhibit tumor angiogenesis and provide new insight into DHA’s anticancer action, further supporting its use in cancer therapy. Examination of small RNA populations in MCF7 cells and exosomes after DHA treatment.
Project description:We hypothesized that miRNAs in the bone maroow mesenchymal stem cells (BM-MSC)-derived exosomes contributed to the phenotype change of breast cancer cells through exosome transfer. We analyzed the miRNA expression signature in BM-MSC-derived exosomes. We compared the miRNA expression levels in exosomes between BM-MSCs and adult fibroblasts (as a control).
Project description:Deregulation of Src kinases is associated with cancer. We previously showed that SrcDN conditional expression in MCF7 cells diminished tumorigenesis and causes tumor regression in mice. However, it remained unclear whether SrcDN affected breast cancer stem cell functionality or it reduced tumor mass. Here, we address this question by isolating an enriched population of BCSCs (ESA+-CD44+-CD24-) and the tumor-differentiated cells (ESA+-CD44+-CD24+) from MCF7-Tet-On-SrcDN. ESA+-CD44+-CD24- grew in suspension forming mammospheres, and producing tumors in nude mice, while ESA+-CD44+-CD24+ were poorly/non-tumorigenic. Doxycycline-induction of SrcDN inhibited BCSC tumorigenesis, selfrenewal, and stem-cell markers expression. SrcDN significantly inhibited SFE, and stem-cell markers expression in triple-negative breast cancer (TNBC) MDA-MB-231 and SUM159PT cells. Inducible depletion of c-Src caused similar effects in MDA-MB-231 cells. In MCF7-Tet-On-SrcDN derived mammospheres SrcDN-induction inhibited expression, and activity of hexokinase, pyruvate kinase and lactate dehydrogenase, resulting in diminished glucose consumption and lactate production, which restricted Warburg effect. Thus, c-Src functionality is important for breast cancer stem cell maintenance and renewal, tumorigenicity, and stem cell transcription factor expression, effects linked to glucose metabolism reduction.
Project description:We analyzed RNA from 2 breast cancer cell lines (MDA-MB-231 (MM231) and MCF7) and exosomes derived from them We used Affymetrix miRNA-3 array to determine the miRNA profile to find out whether miRs content in exosomes and expression levels were different after 17β-estradiol .
Project description:Background: Docosahexaenoic acid (DHA) is a natural compound with anticancer and anti-angiogenesis activity that is currently under investigation as both a preventative agent and an adjuvant to breast cancer therapy. However, the precise mechanisms of DHA’s anticancer activities are unclear. It is understood that the intercommunication between cancer cells and their microenvironment is essential to tumor angiogenesis. Exosomes are extracellular vesicles that are important mediators of intercellular communication and play a role in promoting angiogenesis. However, very little is known about the contribution of breast cancer exosomes to tumor angiogenesis or whether exosomes can mediate DHA’s anticancer action. Results: Exosomes were collected from MCF7 and MDA-MB-231 breast cancer cells after treatment with DHA. We observed an increase in exosome secretion and exosome microRNA contents from the DHA-treated cells. The expression of 83 microRNAs in the MCF7 exosomes was altered by DHA (>2-fold). The most abundant exosome microRNAs (let-7a, miR-23b, miR-27a/b, miR-21, let-7, and miR-320b) are known to have anti-cancer and/or anti-angiogenic activity. These microRNAs were also increased by DHA treatment in the exosomes from other breast cancer lines (MDA-MB-231, ZR751 and BT20), but not in exosomes from normal breast cells (MCF10A). When DHA-treated MCF7 cells were co-cultured with or their exosomes were directly applied to endothelial cell cultures, we observed an increase in the expression of these microRNAs in the endothelial cells. Furthermore, overexpression of miR-23b and miR-320b in endothelial cells decreased the expression of their pro-angiogenic target genes (PLAU, AMOTL1, NRP1 and ETS2) and significantly inhibited tube formation by endothelial cells, suggesting that the microRNAs transferred by exosomes mediate DHA’s anti-angiogenic action. These effects could be reversed by knockdown of the Rab GTPase, Rab27A, which controls exosome release. Conclusions: We conclude that DHA alters breast cancer exosome secretion and microRNA contents, which leads to the inhibition of angiogenesis. Our data demonstrate that breast cancer exosome signaling can be targeted to inhibit tumor angiogenesis and provide new insight into DHA’s anticancer action, further supporting its use in cancer therapy.