Inhibition of a v b 3 integrin impairs adhesion and uptake of tumor-derived small extracellular vesicles
Background: Extracellular vesicles (EVs) are lipid-bound particles that are naturally released from cells and mediate cell-cell communication. Integrin adhesion receptors are enriched in small EVs (SEVs) and SEV-carried integrins have been shown to promote cancer cell migration and to mediate organ-specific metastasis; however, how integrins mediate these effects is not entirely clear and could represent a combination of EV binding to extracellular matrix and cells.
Methods: To probe integrin role in EVs binding and uptake, we employed a disintegrin inhibitor (DisBa-01) of integrin binding with specificity for αvβ3 integrin. EVs were purified from MDA-MB-231 cells conditioned media by serial centrifugation method. Isolated EVs were characterized by different techniques and further employed in adhesion, uptake and co-culture experiments.
Results: We find that SEVs secreted from MDA-MB-231 breast cancer cells carry αvβ3 integrin and bind directly to fibronectin-coated plates, which is inhibited by DisBa-01. SEV coating on tissue culture plates also induces adhesion of MDA-MB-231 cells, which is inhibited by DisBa-01 treatment. Analysis of EV uptake and interchange between cells reveals that the amount of CD63-positive EVs delivered from malignant MDA-MB-231 breast cells to non-malignant MCF10A breast epithelial cells is reduced by DisBa-01 treatment. Inhibition of αvβ3 integrin decreases CD63 expression in cancer cells suggesting an effect on SEV content.
Conclusion: In summary, our findings demonstrate for the first time a key role of αvβ3 integrin in cell-cell communication through SEVs.
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Posted 19 May, 2020
Received 19 May, 2020
On 19 May, 2020
Received 15 May, 2020
On 11 May, 2020
On 10 May, 2020
Invitations sent on 09 May, 2020
On 07 May, 2020
On 06 May, 2020
On 06 May, 2020
Received 01 Apr, 2020
On 01 Apr, 2020
Received 30 Mar, 2020
On 20 Mar, 2020
On 16 Mar, 2020
Invitations sent on 13 Mar, 2020
On 12 Mar, 2020
On 11 Mar, 2020
On 11 Mar, 2020
On 06 Mar, 2020
Inhibition of a v b 3 integrin impairs adhesion and uptake of tumor-derived small extracellular vesicles
Posted 19 May, 2020
Received 19 May, 2020
On 19 May, 2020
Received 15 May, 2020
On 11 May, 2020
On 10 May, 2020
Invitations sent on 09 May, 2020
On 07 May, 2020
On 06 May, 2020
On 06 May, 2020
Received 01 Apr, 2020
On 01 Apr, 2020
Received 30 Mar, 2020
On 20 Mar, 2020
On 16 Mar, 2020
Invitations sent on 13 Mar, 2020
On 12 Mar, 2020
On 11 Mar, 2020
On 11 Mar, 2020
On 06 Mar, 2020
Background: Extracellular vesicles (EVs) are lipid-bound particles that are naturally released from cells and mediate cell-cell communication. Integrin adhesion receptors are enriched in small EVs (SEVs) and SEV-carried integrins have been shown to promote cancer cell migration and to mediate organ-specific metastasis; however, how integrins mediate these effects is not entirely clear and could represent a combination of EV binding to extracellular matrix and cells.
Methods: To probe integrin role in EVs binding and uptake, we employed a disintegrin inhibitor (DisBa-01) of integrin binding with specificity for αvβ3 integrin. EVs were purified from MDA-MB-231 cells conditioned media by serial centrifugation method. Isolated EVs were characterized by different techniques and further employed in adhesion, uptake and co-culture experiments.
Results: We find that SEVs secreted from MDA-MB-231 breast cancer cells carry αvβ3 integrin and bind directly to fibronectin-coated plates, which is inhibited by DisBa-01. SEV coating on tissue culture plates also induces adhesion of MDA-MB-231 cells, which is inhibited by DisBa-01 treatment. Analysis of EV uptake and interchange between cells reveals that the amount of CD63-positive EVs delivered from malignant MDA-MB-231 breast cells to non-malignant MCF10A breast epithelial cells is reduced by DisBa-01 treatment. Inhibition of αvβ3 integrin decreases CD63 expression in cancer cells suggesting an effect on SEV content.
Conclusion: In summary, our findings demonstrate for the first time a key role of αvβ3 integrin in cell-cell communication through SEVs.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6