These robotic cells intelligently seek out and attack cancer that has metastasized.

A team of engineers from the University of California (California) has developed microscopic biorobots that can swim in body fluids. The purpose of these devices is as unique as their design: to deliver oncology drugs directly to metastatic tumors in a controlled manner.

The results of treating cancerous tissues with these hybrid biorobots have been positive and encouraging, as detailed in a recent paper Science Advance Journal. The most recent experiment, conducted on mice, showed that it is possible to suppress tumor growth and its spread to other lungs.

The experimental treatment was administered through a tube inserted into the trachea of ​​the rodents. The animals were diagnosed with melanoma and metastases to the lungs. After receiving microrobots, the average survival of mice was 37 days. Those who did not receive treatment lived an average of only 27 days. The researchers say their treatment method can reduce the required dose of the drug while significantly reducing associated side effects.

This is how microrobots fight cancer

Microrobots are the result of the convergence of disciplines such as biology and nanotechnology. University of California (UC) team combines algae cells Chlamydomonas Reinhardty with nanoparticles loaded with doxorubicin, a key drug in the fight against cancer. The cellular structure provides flagella that enable the robot’s mobility, while the attached nanoparticles release their cargo upon contact with cancer cells. Thus, these microrobots are not silicon devices with microchips, but organic cells modified and programmed to perform specific functions.

The introduction of external therapeutic agents into the body poses a significant challenge. Once a microrobot is developed, researchers must outsmart the patient’s immune system to prevent the payload from being lost before reaching its goal. In this UC study, researchers coated nanoparticles with the membranes of red blood cells, cells specialized in oxygen transport.

This coating of the red blood cell membrane allows the body to mistake the microrobots for its own blood cells. This biological camouflage provides the time needed for anticancer drugs to work. In addition, the coating prevents the occurrence of serious immune reactions such as fever, hives or anaphylaxis.

The importance of examining your lungs

The concept of hybrid biorobots is not new to the University of California team. In September 2022, they applied the idea of ​​algae cells loaded with drugs to fight bacteria that cause pneumonia. In this case, microrobots administered antibiotics, which destroyed the respiratory infection in experimental animals with 100% efficiency.

Treating the lungs presents challenges that are rarely considered. The University of California notes that only a small portion of antibiotics administered intravenously reach the lung tissue. According to the authors of the experiment, treatment of pneumonia and lung cancer is ineffective because of the delivery method, and not because of the weakness of the drug or the resistance of microorganisms associated with these conditions. In a 2022 experiment, pneumonia was cured in mice using 3,000 times fewer antibiotics.

The lungs play a critical role in the process of metastasis. According to UC studies, 20 to 54% of patients with malignancies experience respiratory involvement after an initial cancer diagnosis. However, to date there is no specific treatment for lung metastases. Microrobots represent a promising new strategy for targeting drugs such as doxorubicin directly to diseased tissue.