In Brief
Scientists at the Institute of Nanosciences in Germany have developed a drug delivery method that can effectively send drugs to combat tumor cells through the manipulation of hybrid-sperm micromotors.

Killer Sperm

Humanity’s battle with cancer has goaded us to turn to some of the most unconventional therapies possible in hope of combating the deeply emotional and turbulent disease. Physicians are prescribing electric caps like the Optune to zap tumors away, while others are suggesting the analysis of a quick breath can detect cancer. There might be something a little bit more unorthodox  on the horizon to tackle cancer: physician scientists from the Institute of Nanosciences in Germany claim the answer may be human sperm.

Mariana Medina-Sánchez and her team led a study looking into the unique drug delivery benefits human sperm could provide. The team noticed that when sperm are submerged in an active ingredient found in cancer treating drugs, it can absorb large doses. The sperm can then be assembled into microscopic mechanical harnesses, creating sperm-hybrid micromotors. The iron in these harnesses allows clinicians to manipulate the direction of the sperm with external magnetic fields, which in turn allows doctors to direct the drug-coated sperm in the direction of the tumor.

Once the metal harness reaches a surface, its quick release system relinquishes its grip on the sperm’s and allows them swim away once they reach their target. In theory, this would enable the sperm to burrow deeper into tumor tissue, exposing more cancer cells to the drugs in a more direct way than has been possible by other current treatments.

While Medina-Sánchez’s team has only experimented with bull sperm (as they are similar in size to human sperm) the team noticed that the sperm-hybrid micromotor reduced cancerous cells by 87% in just 72 hours. The method proved to be far more effective than treating cancer cells with the drugs alone.

Revolutionizing Drug Delivery

The sperm-hybrids could be potentially advantageous for the hundreds of thousands of women with gynecological cancers, and perhaps even other diseases of the female reproductive tract. The sperm-hybrid micromotor boasts significant advantages: not only do sperm cells provide added protection when it comes to keeping the drug from degrading prematurely. They also wouldn’t unnecessarily trigger the immune system, like a drug piggybacking on bacteria would.

Drug delivery comes in many forms: swallowing, inhalation, absorption through the skin, or intravenous injections. That being said, it’s not surprising that nanotechnology is a hot topic in drug delivery. Even with new technologies, science seems to have stagnated around several central topics: delivering drugs past the blood-brain barrier, enhancing individual cellular delivery, and combining diagnostics and treatments.

Chemotherapies that inadvertently target non-cancerous cells result in the death of normal cells. This is a consequence that can be avoided if Medina-Sánchez’s sperm-hybrid micromotors are approved by national standards.

While Medina-Sánchez’s new approach does have many questions to left to answer — including how sperm could be introduced into the reproductive system as drug-delivery agents while not also potentially causing pregnancy — the method certainly seems promising.