Bypassing multidrug resistant ovarian cancer using ultrasound responsive doxorubicin/curcumin co-deliver alginate nanodroplets.

Ultrasound-responsive perfluorocarbon nanoemulsions are a class of new multifunctional smart nanocarriers which combine diagnostic properties with therapeutic properties and release their drug payload in a controlled manner in response to ultrasound. Therefore, combination therapy using chemotherapeutic and chemosensitizing agents co-entrapped in these nanocarriers seems beneficial for cancer treatment. In the present study, multifunctional smart alginate/perfluorohexane nanodroplets were developed for co-delivery of doxorubicin and curcumin (a strong chemosensitizer). The nanodroplets with the average particle size of 55.1nm were synthesized via nanoemulsion process. The entrapment efficiency of doxorubicin was 92.3%. To improve curcumin entrapment into the alginate shell, Span 60 was added to the formulation as a co-surfactant and finally curcumin entrapment of about 40% was achieved. Ultrasound-mediated drug release kinetic was evaluated at two different frequencies of 28kHz (low frequency) and 1MHz (high frequency). Low frequency ultrasound resulted in higher triggered drug release from nanodroplets. The nanodroplets showed strong ultrasound contrast via droplet to bubble transition as confirmed via B-mode ultrasound imaging. Enhanced cytotoxicity in adriamycin-resistant A2780 ovarian cancer cells was observed for Dox-Cur-NDs compared to Dox-NDs because of the synergistic effects of doxorubicin and curcumin. However, ultrasound irradiation significantly increased the cytotoxicity of Dox-Cur-NDs. Finally, in vivo ovarian cancer treatment using Dox/Cur-NDs combined with ultrasound irradiation resulted in efficient tumor regression. According to the present study, nanotherapy of multidrug resistant human ovarian cancer using ultrasound responsive doxorubicin/curcumin co-loaded alginate-shelled nanodroplets combined with ultrasound irradiation could be a promising modality for the future of cancer treatment.