Sonosensitive MRI Nanosystems as Cancer Theranostics: A Recent Update

Abstract

In the tireless search for innovative and more efficient cancer therapies, sonosensitive Magnetic Resonance Imaging (MRI) agents play an important role. Basically, these systems consist of nano/microvesicles composed by a biocompatible membrane, responsive to ultrasound-induced thermal or mechanical effects, and an aqueous core, filled up with a MRI detectable probe and a therapeutic agent. They offer the possibility to trigger and monitor in real time drug release in a spatio-temporal domain, with the expectation to predict the therapeutic outcome. In this review, the key items to design sonosensitive MRI agents will be examined and an overview on the different approaches available so far will be given. Due to the extremely wide range of adopted ultrasound settings and formulations conceived, it is hard to compare the numerous preclinical studies reported. However, in general, a significantly better therapeutic outcome was noticed when exploiting ultrasound triggered drug release in comparison to traditional therapies, thus paving the way to the possible clinical translation of optimized sonosensitive MRI agents.

Nano-Enhanced Drug Delivery and Therapeutic Ultrasound for Cancer Treatment and Beyond

“…Supply of high concentration of drug to plasma while being hyperthermia treatment is applied (Liu D. et al, 2016; Garello and Terreno, 2018).…”

Nanocarriers as Magic Bullets in the Treatment of Leukemia

“…T m is defined as the temperature at which a transition occurs from an ordered gel phase to a disordered fluid phase [33]; during this transition, the liposomal payload is generally released, due to the loosening of the tightly packaging of the phospholipid bilayer. The first thermosensitive liposomes developed were mainly composed of phosphatidylcholines, bearing a T m in the range of mild hyperthermia (40-43 • C) [34]. While, ThermoDox TM , a liposomal formulation containing doxorubicin currently in a clinical trial for the treatment of hepatocellular carcinoma (clinicaltrials.org identifier: NCT00617981), exploits the lysolipid thermally sensitive liposome technology to encapsulate doxorubicin and release it selectively at 41.3 • C, thanks to pore formation into the membrane [35,36].…”

“…phosphatidylcholines, bearing a Tm in the range of mild hyperthermia (40-43 °C) [34]. While, ThermoDox TM , a liposomal formulation containing doxorubicin currently in a clinical trial for the treatment of hepatocellular carcinoma (clinicaltrials.org identifier: NCT00617981), exploits the lysolipid thermally sensitive liposome technology to encapsulate doxorubicin and release it selectively at 41.3 °C, thanks to pore formation into the membrane [35,36].…”

Following nanomedicine activation with magnetic resonance imaging: why, how, and what’s next?

“…As opposed to HIFU, which is used to locally increase the temperature and enable payload release from thermosensitive liposomes (see the section on heat-triggered drug release), the triggered delivery of the cargo using pulsed low intensity non-focused ultrasound (pLINFU) relies on mechanical interaction of the nanocontainer with acoustic waves [40,41]. The use of low energy US limits the cytotoxicity related to cavitation effects and heating, and enables the activation of nonthermosensitive nanocontainers [29].…”