Delivery of thymoquinone through hyaluronic acid-decorated mixed Pluronic® nanoparticles to attenuate angiogenesis and metastasis of triple-negative breast cancer.

Triple-negative breast cancer (TNBC) is a highly aggressive and metastatic subtype of breast cancer showing non-responsiveness to most available therapeutic options. Therefore, smart therapeutic approaches to selectively transport and target TNBCs are required. Herein, we developed thymoquinone (TQ)-loaded, hyaluronic acid (HA)-conjugated Pluronic® P123 and F127 copolymer nanoparticles (HA-TQ-Nps) as a selective drug-carrying vehicle to deliver anticancer phytochemical TQ to TNBC cells. The mean size of nanoparticles was around 19.3 ± 3.2 nm. and they were stable at room temperature up to 4 months. HA-TQ-Nps were immensely cytotoxic towards TNBC cells but did not show the toxic effect on normal cells. Detailed investigations also demonstrated its pro-apoptotic, anti-metastatic and anti-angiogenic activity. In-depth mechanistic studies highlighted that HA-TQ-Nps retarded cell migration of TNBC cells through up-regulation of microRNA-361 which in turn down-regulated Rac1 and RhoA mediated cell migration and also perturbed the cancer cell migration under the influence of the autocrine effect of VEGF-A. Moreover, HA-TQ-Np-treatment also perturbed tumor-induced vascularization by reducing the secretion of VEGF-A. The anti-metastatic and anti-angiogenic activity of HA-TQ-Nps was found to be evident in both MDA-MB-231 xenograft chick embryos and 4T1-mammary solid tumor model in syngeneic mice. Thus, an innovative targeted nano-therapeutic approach is being established to reduce the tumor burden and inhibit metastasis and angiogenesis simultaneously for better management of TNBC.