Intratumoral injection of two dosage forms of paclitaxel nanoparticles combined with photothermal therapy for breast cancer.

OBJECTIVE: In order to enhance the efficacy of anti-breast cancer, paclitaxel nanoparticles (PTX NPs) and polypyrrole nanoparticles (PPy NPs) were combined with photothermal therapy and chemotherapy. At the same time, the two dosage forms of PTX NPs and PTX NPs gel were compared. METHODS: PTX NPs were prepared by self-assembly method, and then the cytotoxicity in vitro was investigated by Methyl thiazolyl tetrazolium (MTT) and other methods, and the efficacy and side effects in vivo were further investigated. RESULTS: The average hydrated diameter, PDI and electric potential of PTX NPs were (210.20 ± 1.57) nm, (0.081 ± 0.003) mV and (15.80 ± 0.35) mV, respectively. MTT results showed that the IC(50) value of PTX NPs on 4 T1 cells was 0.490 μg/mL, while that of PTX injection was 1.737 μg/mL. The cell inhibitory effect of PTX NPs was about 3.5 times higher than that of PTX injection. The tumor inhibition rates of PTX NPs and gel were 48.64% and 56.79%, respectively. Together with local photothermal stimulation, the tumor inhibition rate of the PTX NPs reached 91.05%, surpassing that of the gel under the same conditions (48.98%), moreover, the organ index and H&E staining results of PTX NPs showed a decrease in toxicity. CONCLUSION: This combination therapy can significantly enhance the effect of anti-breast cancer, and the synergistic effect of chemotherapy and light and heat provides a feasible and effective strategy for the treatment of tumor.