Protease Cargo in Circulating Exosomes of Breast Cancer and Ovarian Cancer Patients

Document Type : Research Articles


1 Institute of Chemical Biology and Fundamental Medicine, SB RAS, Novosibirsk, Russia.

2 Novosibirsk State University, Novosibirsk, Russia.

3 Cancer Research Institute, Тomsk National Research Medical Center, Russian Academy of Science, Tomsk, Russia, Tomsk, Russia.

4 Siberian State Medical University, Tomsk, Russia.

5 Regional Clinical Oncological Hospital, Novosibirsk, Russia.

6 Novosibirsk Research Institute of Circulation Pathology Academician E.N. Meshalkin, Novosibirsk, Russia.


Background: As is known, exosomes play an important role in promoting progression of cancers by increasing
its invasive potential. The aim of this study was to evaluate the levels of tetraspanine-associated (ADAM-10) and
tetraspanine-nonassociated proteases (20S proteasomes) in exosomes from culture medium, plasma exosomes of
patients with breast tumors and plasma and ascites of ovarian tumor patients. Methods: MCF-7 and SVO-3 culture
mediums and blood samples from healthy females (n = 30, HFs), patients with diffuse dyshormonal dysplasia of the
breast (n=28, BBTPs), breast cancer patients (n=32, BCPs), borderline ovarian tumor patients (n=20, BOTPs) and
blood and ascites samples ovarian cancer patients (n=35, OCPs) were included in the study. Exosomes from plasma,
ascites and culture mediums were isolated and characterized in according to Extracellular Vesicles Society. The
expression levels of 20S proteasome and ADAM-10 in exosomes were determined using flow cytometry and western
blot analysis, correspondingly. Results: The subpopulation composition of the exosomes from MCF-7 culture medium
and from blood plasma of HFs and breast diseases patients is similar, however CD9/CD24 subpopulation significantly
increased at cell supernatant. The similar results was obtained for exosomes from SVO-3 medium and blood plasma
and ascites of ovary tumor patients, but CD9/CD24 subpopulation significantly decreased at cells and illness samples,
however CD63/CD24 exosomes increased significantly from cell supernatant. 20S proteasome level is significantly
increased in exosomes from MCF-7 and SVO-3 culture medium, breast tumor patients and OCPs plasma in comparison
to HUVEC culture medium and HFs plasma samples. At CD9-positive exosomes from BCPs plasma and MCF-7 was
reveal a high expression of ADAM-10 and low expression is from BBDPs plasma and ovarian tumor patients plasma/
ascites samples. Exosomes from ascites OCP had high expression of ADAM-10 in the CD24-positive subpopulation.
Conclusion: Breast and ovarian cancer development is connected with functioning of immune proteasome forms in
plasma and ascites exosomes, while increased ADAM10 expression at CD9-positive exosome was associated with
breast cancer and at CD24-positive subpopulation – with ovarian cancer. Obtained data confirm role of exosomal
proteases in tumor progression.


Main Subjects