Chemical engineers at Massachusetts Institute of Technology (MIT) have created a new sensor that helps in monitoring cancer therapy response by allowing visibility inside tumour cells.
The sensor is designed to detect hydrogen peroxide in human cells. It consists of a modified peroxiredoxin protein with two fluorescent molecules.
Peroxiredoxin is known to get oxidised with a rise in levels of hydrogen peroxide. The sensor glows red when it detects hydrogen peroxide but displays green if there is no molecule.
This capability to detect hydrogen peroxide is expected to facilitate the identification of new cancer therapies that increase hydrogen peroxide levels and trigger programmed cell death.
MIT chemical engineering associate professor Hadley Sikes said: “The same therapy isn’t going to work against all tumours. Currently, there’s a real dearth of quantitative, chemically specific tools to be able to measure the changes that occur in tumour cells versus normal cells in response to drug treatment.”
Mutations that lead to the production of abnormal hydrogen peroxide levels, which damages cells, are said to be common in cancer cells. These cells depend on antioxidant systems to remove the harmful molecules.
Various ‘redox drugs’ are currently being developed to disable the antioxidant systems or boost hydrogen peroxide production to ultimately result in cancer cell death. However, not all patients respond to such cancer therapy, and the new sensor is intended to address this concern by aiding clinicians in measuring a cell’s response to these drugs.
The team assessed the sensor in human cancer cells that were susceptible, as well as those resistant to a redox drug called piperlongumine.
It was observed that hydrogen peroxide levels increased in the susceptible cells, while they remained unchanged in the resistant cells.
In addition to the identification of effective cancer therapies, the researchers expect the new sensor will be potentially useful in screening individual patients’ tumours to predict the efficacy of the treatments to be used.