Therapeutic Effects of Mesenchymal Stem Cells Carrying Echovirus inMouse Models of Breast Cancer

INTRODUCTION: Breast Cancer (BC) is treatable in early stages but has high mortality rates in advanced cases, highlighting the need for better treatment methods. Oncolytic Viruses (OVs) have emerged as a promising approach to specifically target and kill BC tumor cells, although their effectiveness is limited by the immune response. To overcome this challenge, researchers are investigating the use of cell carriers. This study aims to evaluate the effects of mesenchymal stem cells carrying Echovirus (MSCs-ECHO) in a BC mouse model. METHOD: The effectiveness of MSCs-ECHO was evaluated in a mouse model of BC induced by the subcutaneous injection of live 4T1 cells (1×104) in female Balb/c mice. Its effects were assessed using several parameters, including Tumor Size (TS), Survival Probability (SP), and indicators of immune system response, such as the Splenocyte Proliferation Index (SPI), Nitric Oxide (NO), Lactate Dehydrogenase (LDH), and cytokines (IL-4, IL-10, IFN-γ, and TGF-β) in the supernatant of splenocytes. RESULTS: Our findings revealed that treatment with MSCs-ECHO significantly increased SP, SPI, LDH, NO, and IFN-γ levels, while reducing TS, TGF-β, IL-4, and IL-10 levels in treated mice compared to the control group. Additionally, MSCs-ECHO demonstrated superior therapeutic effects compared to treatment with cell-free virus. CONCLUSION: These findings indicate that ECHO treatment may represent a promising therapeutic approach for BC. Based on the results of the present study, the utilization of MSCs as carriers for OV appears to be a viable complementary strategy in the management of BC.