Bladder cancer, a common and challenging disease, has led researchers to explore innovative treatment approaches. One such approach involves the use of self-powered nanoparticles, known as nanomotors, which offer a promising solution for drug delivery. These nanomotors have the ability to navigate complex fluid environments, a task beyond the reach of traditional drugs and passive nanoparticles. By converting the chemical energy of the surrounding fluid into mechanical thrust, nanomotors open up exciting possibilities for biomedical applications.
One strategy involves the use of glucose oxidase (Gox), an enzyme that converts glucose into gluconic acid and hydrogen peroxide (H2O2). This reaction, however, requires oxygen (O2), which can be limited in tumor environments. To address this challenge, researchers developed a bio-mineralization technique to create Gox-Mn nanoparticles. These nanoparticles, known as nanozymes, generate oxygen from H2O2 in the tumor microenvironment, supporting the glucose consumption and glycolysis process. This self-amplifying cycle intensifies glucose depletion, promoting a cancer starvation therapy.
Building on this strategy, researchers created a novel multifunctional nanomotor (UG-M@Gem) by combining Gem-loaded tumor-membrane nanoparticles (M@Gem) with triple-enzyme-active nanoparticles (UG). This design leverages the catalytic activities of enzymes to enhance drug delivery and efficacy. Unlike traditional nanomotors, which require complex synthesis steps, this study simply conjugates drug-loaded membrane nanoparticles with the power source (UG) to achieve an asymmetric distribution of urease. This approach not only simplifies the synthesis process but also maintains the activity of urease, a critical component for self-propulsion.
Following intravesical instillation, the urease on the nanomotors catalyzes the conversion of urea in urine into carbon dioxide and ammonia, generating a self-propulsion force. This force enables the rapid movement of nanoparticles, allowing them to penetrate deep into the bladder wall. The tumor-membrane homing directs the nanomotors to gather at tumor sites, achieving targeted and deep-penetrating tumor treatment. Once internalized by tumor cells, the Gox enzyme oxidizes intratumoral glucose, producing gluconic acid and H2O2, creating an H2O2-rich microenvironment. The released manganese ions then catalyze H2O2 into oxygen, compensating for the oxygen consumption by Gox. This self-amplified glucose depletion effectively kills tumor cells, while the Gem in the membrane nanoparticles is gradually released.
The biocompatibility of all nanomotor components holds promise for clinical translation. In vitro and in vivo studies have demonstrated the superior penetration capabilities and antitumor effects of these nanomotors. The preclinical data strongly support the potential of these dual-spherical nanomotors as a promising platform for bladder cancer treatment, warranting further exploration for clinical applications.
This innovative approach offers a new perspective on cancer treatment, combining the power of nanotechnology and enzyme-based therapies. While further research is needed, the potential impact on bladder cancer treatment is significant, offering hope for improved outcomes and quality of life for patients.
