Researchers in Japan have developed an experimental strategy that uses carbon monoxide produced by cancer cells to make an anticancer compound inside them. In tests on cultured cells, the approach generated the compound in cancer cell lines but not in a noncancerous cell line, according to research led by Katsunori Tanaka at RIKEN’s Pioneering Research Institute and published in Nature Communications.
The team’s method uses a palladium-based catalyst enclosed in albumin, a protein found in blood. The carrier is designed to protect the catalyst from glutathione, which can otherwise deactivate it inside cells. In cancer cells, carbon monoxide helps the catalyst produce phenanthridinone, a molecule with derivatives used in anticancer drugs.
Researchers exposed cultured liver, cervical, breast and lung cancer cells, as well as a noncancerous cell line, to the albumin-and-catalyst complex for 48 hours. They detected phenanthridinone in the cancer cells, but not in the normal cells. After modifying the system to produce a more toxic derivative, the team observed that compound forming inside cultured liver cancer cells, which then showed signs of damage.
The researchers also tested whether carbon monoxide in blood could trigger drug production before the system reached a tumor. The drug was not produced in blood in their laboratory tests. They suggest this may be because carbon monoxide there is largely bound to hemoglobin and unavailable for the reaction.
The findings are an early laboratory demonstration, not evidence that the approach is safe or effective in patients. The researchers plan to test it in animal models.
Sources: ScienceDaily.