Tabriz University of Medical Sciences Medical Journal of Tabriz University of Medical Sciences 2783-2031 42 5 2020 12 30 The effects of Silibinin on nitrosative stress and matrix metalloproteinase -9 expression in Balb/c mice with breast cancer tumor 529 536 10.34172/mj.2020.076 EN Farhad Soleimani https://orcid.org/0000-0003-0625-1073 Rasoul Sharifi https://orcid.org/0000-0001-5079-5655 Minoo Mahmoodi https://orcid.org/0000-0002-3541-8832 Mehrdad Kasaee https://orcid.org/0000-0002-0066-9260 Journal Article 10.34172/mj.2020.076 2019 02 28 Background: Among the factors associated with cancer are the nitrosative stress and increased expression of some Matrix Metalloproteinase (MMP). Silibinin has an anti-tumor effect, therefore, the present study evaluates the effects of slibinin on nitrosative stress indices and Matrix Metalloproteinase -9 (MMP-9) expression in the animal models of breast cancer. Methods: In this study, 48 Balb/c mice were divided into 6 groups (each group contains 8 mouse): healthy ( control and cancer ) and treatment groups: treatment groups included cancerous mice which receiving 20 mg, 40 mg and 80 mg of silibinin for 3 weeks. In order to induce cancer, 4T1 cell line was used. After enrolling serum and breast tumor samples, NO level and MMP-9 expression in breast tumor biopsy were evaluated. Data were analyzed using one-way ANOVA, Kruskal-Wallis and T-test (p <0.05). Results: The results revealed that the use 80 mg of silibinin resulted in significantly decreased in NO level in cancerous mice(170.88±15.42μM/ml) compared with untreated cancerous mice(190.38±21.19 μM/ml) (p=0.05). Furthermore, the use of three dose of silibinin led to a non-significant reduction of MMP-9 in the treatment group compared to untreated cancerous mice. Conclusion: Silibinin treatment has been shown to improve nitrosative stress in breast cancer mice.