Nanoparticles and protein can challenge cancer

Russian scientists have developed new polymer-based nanoparticles for targeted delivery of anti-tumor drugs.

A collaborative team from Mendeleev University and two more Moscow-based research hubs has come up with nanoparticles that, when bonded to a specific protein called cytokine (designated TRAIL DR5), become capable of causing death of cancer cells. In the experiments, the cytokine closely interacted with the so-called “death receptors” on the surface of tumorous cells, thus triggering their self-destruction.

The human body is a self-regulating system that always keeps cells’ growth and development under control. The system “marks” the cells in which pathological change has been spotted, and then kick-starts the process of their self-annihilation. The cytokine proteins play a crucial role in this and have long been looked into as possible vehicles for cancer therapy.

Many attempts have been made across the world to harness the counter-tumor properties of the cytokine since the TRAIL was first discovered 25 or so years ago. Serious problems have been faced in the process, though. The TRAIL works with some cancer types and fails with others; why some tumorous cells can resist the protein and others can’t has yet to be fully understood. In addition, the human body may or may not generate enough cytokines to inhibit a tumor as it starts growing. The free (unbonded) TRAIL could be administered artificially, but the kidneys discharge it too fast for the protein to be able to do its expected job.

According to Dr. Andrei Kuskov of Mendeleev University, one of the co-experimenters, his team secured the molecules of the DR5-specific cytokine on the surface of polymer-based nanoparticles. The researchers found that the protein-nanoparticles conjugation stepped up the cytokine’s ability to kill cancer cells. What’s more, it took much fewer cytokines in their bonded form to achieve good enough therapeutic effect - just one-tenth of what would have been needed if the free protein had been used.

It is critical to note that healthy human cells that surrounded the cancer ones were left unscathed in the experiment. Research with breast adenocarcinoma cells has led the team to believe that the DR5-specific cytokine concentrates on its target and sends afflicted cells a very powerful signal that triggers their self-destruction.

Source