Can Microrobots Cure Cancer?

Written: February 2023

The risk of dying from cancer in the United States has decreased over the past 28 years according to annual statistics reported by the American Cancer Society (ACS). The cancer death rate for men and women combined fell 32% from its peak in 1991 to 2019, the most recent year for which data were available. The decline in the cancer death rate translates to almost 3.5 million fewer cancer deaths during these years than what would have been expected if the death rate had not fallen. Although the trend line is good, a total of 1.9 million new cancer cases and 609,360 deaths from cancer are expected to occur in the US in 2022, which is about 1,670 deaths a day.

Several factors have contributed to the lower cancer mortality. A large factor is fewer people smoking. Other factors include prevention, screening, early diagnosis, and treatment. Treatments include surgery, chemotherapy, radiation therapy, immunotherapy, stem cell or bone marrow transplant, hormone therapy. There is plenty of room to believe in our overall potential to move closer to a world without cancer.

Despite some reasons for optimism about cancer, issues remain. One is the high cost of treatment. The pharmaceutical industry sees cancer treatment as a high growth and high profit opportunity. They are spending billions on acquisitions and R&D to develop breakthrough cures. They expect high returns on investment. A study by the West Health Policy Center, a nonprofit and nonpartisan policy research group, found more than 1.1 million Medicare patients could die over the next decade because they cannot afford to pay for their prescription medications.

In addition to financial toxicity, there is toxicity of chemotherapy. Chemotherapy can be effective in inhibiting or killing cancer cells. Unfortunately, the chemo often does a lot of collateral damage to other parts of the body. Losing hair is just one example. Numerous studies have evaluated whether chemotherapy does more harm than good.

If it was possible to deliver drugs directly to cancer cells, it could help reduce the unpleasant symptoms. Now, in a proof-of-concept study, researchers reporting in ACS Nano made fish-shaped microrobots that are guided with magnets to cancer cells, where a pH change triggers them to open their mouths and release their chemotherapy cargo directly at the cancer cells. A video is worth a thousand words. Watch a video of the microrobots in action.

The research is in the early stages, but the proof of concept showed optimism the goal can be achieved. Delivering chemotherapy without the side effects would be more than welcomed. Cancer’s days may be numbered.