Ultrasound-Induced Microbubble Cavitation Combined with Paclitaxel-Loaded Nanoparticles for the Elimination of PC-3 Cells in vitro

Castration-resistant prostate cancer (CRPC) and its metastases are the main reasons for the high mortality of prostate cancer. Currently, paclitaxel (PTX)-based chemotherapeutics are used as first-line drugs to treat CRPC, but this treatment does not show good effects and is accompanied by serious side effects, which may be because intravenously injected chemotherapeutic drugs have difficulties gathering at the tumor site. Therefore, a safe and effective drug delivery carrier is urgently needed to enhance the therapeutic effects of chemotherapeutic drugs against CRPC. Methoxy polyethylene glycol-polylacticco-glycolic acid-polylysine (mPEG-PLGA-PLL) nanoparticles (NPs) have shown high drug encapsulation efficiency and good therapeutic effects against ovarian cancer and pancreatic cancer, but there are few studies on their treatment against CRPC. To expand the applications of mPEG-PLGA-PLL NPs, in this study, mPEG-PLGA-PLL NPs loaded with PTX (PTX-NPs) were synthesized. The synthesized PTX-NPs had a uniform particle size and no obvious aggregation. PTX-NPs can be uptaked by PC-3 cells, which significantly promotes the inhibition of proliferation and apoptosis effects of PTX on cells and reduces the expression levels of CDK6, Cyclin D1 and Bcl-2 (cyclins and an apoptosis inhibitor), and these effects can be further enhanced by ultrasound-induced microbubble cavitation (UIMC). Our research provides a new nanocarrier for the treatment of CRPC, laying the foundation for further research in the future.