ABSTRACT
BACKGROUND: There are currently a number of barriers hindering the successful treatment of breast cancer, including the metastatic spread of cancer cells. In looking for new anticancer agents, we reported two novel hydrazide derivatives with anti-cancer activity in human breast cancer cells. The current study aims to explore the therapeutic potential of the most effective one, N'-((5-nitrothiophen-2-yl)methylene)-2-(phenylthio)benzohydrazide (compound B), on metastatic breast cancer, which is resistant to available chemotherapeutics. METHODS: 4T1 mammary carcinoma cells were inoculated into the fat pad mammary of 5-7-week-old female BALB/c mice and then the effective compound was intraperitoneally administered for 4 weeks. Proliferation index and angiogenesis in tumor and lung tissues were examined with immunohistochemistry. In vitro assessments were also carried out to evaluate the effect of the compound on invasion of MDA-MB-231 cells. RESULTS: Our results demonstrated that this effective derivative significantly inhibited invasion of MDA-MB-231 cells in vitro as shown by Matrigel assay and quantitative real-time method for MMP-9 expression after 48 h of treatment. Daily administration of the compound suppressed the growth of primary tumor and its metastasis to lung, which was confirmed by H&E experiment at a dose of 1 mg/kg in a well-known metastatic model of 4T1 breast cancer in syngeneic BALB/c mice. These outcomes were supported by the immunohistochemical examinations of the tumor and lung tissues of mice. Tumors and lungs in mice treated with the effective compound showed a reduced proliferation index and a smaller microvessel density compared to the control. CONCLUSION: This study highlights an anti-metastatic role for a novel hydrazide derivative in both in vitro and in vivo models of breast cancer.