47 research outputs found
Exosomes derived from mesenchymal stem cells enhance radiotherapy-induced cell death in tumor and metastatic tumor foci
We have recently shown that radiotherapy may not only be a successful local and regional treatment
but, when combined with MSCs, may also be a novel systemic cancer therapy. This study aimed to investigate the
role of exosomes derived from irradiated MSCs in the delay of tumor growth and metastasis after treatment with
MSC + radiotherapy (RT). The tumor cell loss rates found after treatment with the combination of MSC and RT and for exclusive RT, were:
44.4% % and 12,1%, respectively. Concomitant and adjuvant use of RT and MSC, increased the mice surviving time 22,5%
in this group, with regard to the group of mice treated with exclusive RT and in a 45,3% respect control group. Moreover,
the number of metastatic foci found in the internal organs of the mice treated with MSC + RT was 60% less than the
mice group treated with RT alone. We reasoned that the exosome secreted by the MSC, could be implicated in tumor
growth delay and metastasis control after treatment. Our results show that exosomes derived form MSCs, combined with radiotherapy, are determinant in
the enhancement of radiation effects observed in the control of metastatic spread of melanoma cells and suggest that
exosome-derived factors could be involved in the bystander, and abscopal effects found after treatment of the tumors
with RT plus MSC. Radiotherapy itself may not be systemic, although it might contribute to a systemic effect when used
in combination with mesenchymal stem cells owing the ability of irradiated MSCs-derived exosomes to increase the
control of tumor growth and metastasis.This work was supported by CNPq, Conselho Nacional de
Desenvolvimento CientĂfico e TecnolĂłgico â Brasil, Junta de AndalucĂa,
project of Excellence from Junta de AndalucĂa P12-CTS-383 to FJO, Spanish
Ministry of Economy and Competitiveness SAF2015-70520-R to FJO and
JMRdA, RTICC RD12/0036/0026 and CIBER CĂĄncer ISCIII CB16/12/00421 to
FJO
Circulating Extracellular Vesicles Contain miRNAs and are Released as Early Biomarkers for Cardiac Injury
Extracellular Vesicle (EV) Array: microarray capturing of exosomes and other extracellular vesicles for multiplexed phenotyping
Background: Exosomes are one of the several types of cell-derived vesicles with a diameter of 30–100 nm. These extracellular vesicles are recognized as potential markers of human diseases such as cancer. However, their use in diagnostic tests requires an objective and high-throughput method to define their phenotype and determine their concentration in biological fluids. To identify circulating as well as cell culture-derived vesicles, the current standard is immunoblotting or a flow cytometrical analysis for specific proteins, both of which requires large amounts of purified vesicles. Methods: Based on the technology of protein microarray, we hereby present a highly sensitive Extracellular Vesicle (EV) Array capable of detecting and phenotyping exosomes and other extracellular vesicles from unpurified starting material in a high-throughput manner. To only detect the exosomes captured on the EV Array, a cocktail of antibodies against the tetraspanins CD9, CD63 and CD81 was used. These antibodies were selected to ensure that all exosomes captured are detected, and concomitantly excluding the detection of other types of microvesicles. Results: The limit of detection (LOD) was determined on exosomes derived from the colon cancer cell line LS180. It clarified that supernatant from only approximately 104 cells was needed to obtain signals or that only 2.5×104 exosomes were required for each microarray spot (~1 nL). Phenotyping was performed on plasma (1–10 µL) from 7 healthy donors, which were applied to the EV Array with a panel of antibodies against 21 different cellular surface antigens and cancer antigens. For each donor, there was considerable heterogeneity in the expression levels of individual markers. The protein profiles of the exosomes (defined as positive for CD9, CD63 and CD81) revealed that only the expression level of CD9 and CD81 was approximately equal in the 7 donors. This implies questioning the use of CD63 as a standard exosomal marker since the expression level of this tetraspanin was considerably lower