Zahra Abbasi-Malati
1 
, Çığır Biray Avci
2, Parisa Khanicheragh
3, Zeinab Aliyari Serej
1, Maryam Sabour Takanlou
2, Leila Sabour Takanlou
2, Seyed Ghader Azizi
4, Reza Rahbarghazi
5* , Zohreh Sanaat
6, Nafiseh Didar Khosrowshahi
7, Hassan Amini
8, Rasoul Hosseinpour
9,101 Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
2 Department of Medical Biology, Faculty of Medicine, Ege University, Izmir, Turkey
3 Stem Cell and Regenerative Medicine Institute (SCARM), Tabriz University of Medical Sciences, Tabriz, Iran
4 Clinical Immunology Research Center, Zahedan University of Medical Sciences, Zahedan, Iran
5 Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
6 Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
7 Stem Cell and Tissue Engineering Research Laboratory, Sahand University of Technology, Tabriz, 51335-1996, Iran
8 Department of General and Thoracic Surgery, Tabriz University of Medical Sciences, Tabriz, Iran
9 Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
10 Department of Medical Nanotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
Abstract
Introduction: Breast cancer (BC) is a devastating condition with high morbidity and mortality rates in females. Autophagy is an early-stage cell response against stressful conditions. Emerging data have revealed the autophagy-angiogenesis interaction in terms of tumor development and metastasis.
Methods: Here, the angiogenesis behavior of human MDA-MB-231 cells was monitored after modulation of autophagy response in the presence of free 3-methyladenine (3-MA), metformin (Met), or drug-loaded exosomes (3-MA@Exos and Met@Exos). Orthotopic transplantation was done using human BC cell-laden alginate/gelatin (Alg/Gel) microspheres in mice after treatment with Met and/or 3-MA.
Results: Met, and/or Met@Exos increased the cell migration rate and promoted human endothelial cell migration compared to the control cells (P<0.05). However, these features were blunted in 3-MA and 3-MA@Exos groups (P<0.05). Flow cytometry analysis revealed that the drug loading into Exos did not influence internalization capacity or cell survival (P>0.05). ELISA revealed that vascular endothelial growth factor (VEGF) levels were reduced in Met and 3-MA-treated cells, with more pronounced reductions in the free 3-MA groups. Real-time PCR analysis showed diminished expression of several angiogenesis-related genes, except for platelet endothelial cell adhesion molecule-1 (PECAM-1) in the Met@Exos, 3-MA, and 3-MA@Exos groups. Met treatment increased the metastasis and tumor formation in mice mammary glands after orthotopic transplantation of BC tumoroids.
Conclusion: These data indicate that autophagy modulation can alter the angiogenesis and metastatic behavior of human BC cells in vitro and in vivo. Exos are valid bio-shuttles for the delivery of autophagy modulators in CSC-targeted therapies.