Biomarker Could Indicate Response to Colorectal Cancer Drug

Researchers in a recent study discovered a molecule that could potentially dampen the effects of chemotherapy in patients with colorectal cancer (CRC).

Since approximately 50% of patients do not respond to first-line treatment, choosing the proper chemotherapy to treat the cancer can be difficult.

“The challenge is that we do not know beforehand in which 50% the treatment will work. This means we have to treat all patients in the same way - including the 50% who do not benefit,” said lead researcher Claus Lindbjerg Andersen, PhD.

Researchers in the study, which was published by Nature Communications, discovered a molecule associated with the effects of Oxaliplatin, an anticancer drug used to treat CRC. They discovered that patients who have tumors positive for the molecule have a 6 times greater chance of being treatment-resistant compared with those whose tumor is negative for the molecule.

Cancer cells that express a microRNA molecule do not respond to treatment. The researchers were able to show that this molecule prevents cells from dying, according to the study.

“In principle, this discovery opens up for the possibility to examine if a patient's tumor has the microRNA biomarker before treatment is initiated,” said Dr Andersen.

Patients whose tumor expresses this biomarker should receive other treatment that would likely be beneficial, and can avoid the adverse effects of ineffective treatments. Researchers believe that combination therapy could be an effective, new approach.

“Our discovery also opens up for development of new treatment strategies as we have shown that if the microRNA is eliminated from the tumor, the effect of Oxaliplatin is restored,” Dr Andersen concluded.