Design and Characterization of Liposomal Methotrexate and Its Effect on BT-474 Breast Cancer Cell Line

Breast cancer is the most common type of cancer among women worldwide. Traditional treatments, including chemotherapy, surgery, mastectomy, and radiotherapy, are commonly used. Because of the limitation of the aforementioned methods, novel treatment strategies are needed. Methotrexate is a chemotherapeutic drug, which is commonly used to treat breast cancer. Because of the side effects of the free drug, the liposomal form of the drug is suggested.

Liposomal methotrexate was prepared and the encapsulation efficiency was measured. Moreover, the particle size and the zeta potential were measured. The liposome morphology was confirmed using transmission electron microscopy. The MTT assay was done to examine the cytotoxicity of free and encapsulated methotrexate on BT-474 cell line. The Annexin-V/PI dual staining assay was performed to assess the apoptosis in BT-474 breast cancer cells via the flow cytometry method.

The transmission electron microscopy results confirmed the integrated and spherical structure of the nanoparticles. The results of drug release showed that in acidic pH (5.4), more than 90% of the drug was released after 24 hours, which was higher than 2 other pHs. Furthermore, the IC50 value of liposomal methotrexate was determined as 2.15 and 0.82 mg/mL for 24 and 48 hours. The flow cytometry results confirmed that liposomal methotrexate had a greater cytotoxic effect on cancer cells compared with free methotrexate.

Because of the advantages of liposomal based nanocarriers, in this study, liposomal methotrexate could be suggested as an appropriate candidate to treat breast cancer.