Enhanced cytotoxic activity of beta carotene conjugated liposomes towards breast cancer cell line: comparative studies with cyclophosphamide.

This work aims to evaluate cyclophosphamide (Cyclo) cytotoxic efficacy combined with liposomes in the presence or absence of beta carotene (beta) by detecting the effects of these compounds on the breast cancer cell line (MCF-7) DNA damage. The IC50 value for beta in cytotoxic assay with MCF-7 treated cells was 21.15 μg/ml, while with liposomal beta (LipoBeta) being 121 μg/ml. The free Cyclo IC50 value was 719.86 μg/ml, its liposomal form (LipoCyclo) was 172 μg/ml. The results indicated that in contrast with Cyclo and control values, all comet assay parameters for the LipoBeta were significantly increased (P < 0.05). In MCF-7 cells treated with beta, the findings show a higher intensity of comet tail than those treated with LipoBeta. The presence of several double-strand breaks suggests this high intensity relative to the head. The molecular combination between Cyclo and liposomes in the presence or absence of beta was characterized. Dynamic light scattering measurements confirmed the mono-dispersity of all samples. The incorporation of Cyclo or beta into liposomes exhibited a slight shift to higher temperature compared to the main peak of empty liposomes that exists at 101.5°C which creates a conformational disorder within the phospholipids. The FTIR study showed structural alterations in vesicles after liposome encapsulation.