Functionalization of Carbon Nanotubes Loaded with Tamoxifen and Their Anticancer Potential against Human Breast Cancer Cells

Carbon nanotubes (CNTs) serve as molecular carriers for in vivo and in vitro delivery. Initial studies have suggested that nanotubes in drug delivery can enhance the therapeutic response to anti-cancer drugs. The present study intended to investigate the effect of CNTs carrying tamoxifen (TAM-CNTs) on the induction of apoptosis in the MDA-MB-231 cell line.

The cells were treated with various concentrations of TAM and TAM-CNTs. The IC50 for these compounds was determined using a MTT assay. The cells were then treated with a lower concentration of IC50. The BAX and BCL-2 genes expression were evaluated by Real-Time PCR and Western blot. Flow cytometry was employed for evaluating apoptosis induction by TAM and TAM-CNTs.

The IC50 value of TAM and TAM-CNTs in a 48-hour period was 66.19 mg/mL and 36.59 mg/mL, respectively. The results demonstrated that BAX in the cells treated with TAM and TAM-CNTs was upregulated 3.64 and 7.88 times, respectively (P <0.05). Conversely, BCL-2 was downregulated 3.98 and 5.31 times (P <0.05). Furthermore, Western blot experiments confirmed the expression of BAX and BCL-2 proteins based on their gene expression. Flow cytometry results indicated that the viability of MDA-MB-231 cells in the control group, TAM-treated, and TAM-CNTs-treated cells was 95.3%, 64.9%, and 13.75%, respectively. This suggests that TAM-CNTs significantly diminishes cell viability compared to TAM (P <0.001).

The findings revealed that TAM accompanied by CNTs exhibits a greater cytotoxic and apoptotic effect on MDA-MB-231 cells.