(CR)4-Targeted Liposomal Doxorubicin as Promising Therapeutic Approach for Breast Cancer Therapy

One of the main causes of death globally is cancer, hence the present study is based on the designing and formulation of DOX-loaded pegylated liposomal systems. Further, the surfaces of the prepared formulation were modified with the (CR)₄ peptide to improve the efficiency and targeting with reduced systemic side effects. Both LD (DOX-loaded liposomes) and LDM (DOX-loaded surface-modified liposomes) were prepared by remote loading technique and optimized using Box-Behnken design (BBD) within the Response Surface Methodology (RSM). LDM showed spherical shape, vesicle size 118.5 ± 1.28 nm, PDI 0.291 ± 0.006, zeta potential 12.35 ± 0.91 mV, and % entrapment efficiency 67.344 ± 1.27%. In vitro drug release from LDM at pH 6.8 was approximately 66.66 ± 1.98% after 72 h. Using the SRB assessment, in vitro cytotoxicity investigations showed that LDM displayed the most potent cytotoxicity, especially against MCF-7 (breast cancer) with an IC₅₀ of 4.9 ± 0.91 µM, and demonstrated a cytotoxicity hierarchy of HCT-116 < MiaPaca-2 < A549 < MCF-7. Reactive oxygen species production, increased nuclear fragmentation, and variations in the potential of the mitochondrial membrane were all seen in the LDM. LDM exhibited significantly lower hemolysis (4.23 ± 0.17%) compared to the free drug (D) (44.5 ± 0.23%), with no adverse effects on blood coagulation pathways. In vivo, biodistribution, and histopathological studies revealed that LDM exhibited sustained drug release and highest retention in tumor tissue with minimal organ toxicity, as compared to formulations D and LD. So, LDM demonstrates outstanding safety and compatibility for treating breast cancer, exhibiting potent anti-tumor effects while being well-tolerated, making it a potentially effective therapeutic choice.