Danish researchers identified a microRNA shown to predict whether a patient with colorectal cancer would be resistant to oxaliplatin treatment, a discovery that holds promise of improving both current treatment options and development of future treatment strategies.1

Many chemotherapeutic regimens are available to treat colorectal cancer; however, approximately 50% of patients do not respond to the first-line treatment, making choosing the most effective treatment difficult. Adding to this challenge is that resistance is impossible to predict; therefore, patients often undergo treatments that are ineffective and have to cope with the side effects of the treatment, as well.

A team of researchers at Aarhus University Hospital, Aarhus, Denmark, found a molecule closely associated with the effects of oxaliplatin, an anticancer drug commonly used to treat colorectal cancer. The molecule, a microRNA known as miR-625-3p, could serve as a biomarker to predict the likelihood of treatment resistance.

The researchers found the risk of treatment resistance was 6 times higher in patients whose tumors expressed this molecule. Their research has also shown that miR-625-3p directly prevents a normal response to the drug. However, they were able to show that if the microRNA is eliminated from the tumor, response to oxaliplatin treatment is restored.

With this information, clinicians can identify which patients are not likely to respond to oxaliplatin and choose a different treatment regimen at the outset. It also creates avenues for development of new treatment strategies that have a better potential for effectively treating colorectal cancer in these patients.

Reference

1. Rasmussen MH, Lyskjær I, Jersie-Christensen RR, et al. miR-625-3p regulates oxaliplatin resistance by targeting MAP2K6-p38 signalling in human colorectal adenocarcinoma cells. Nat Commun. 2016 Aug 16. doi: 10.1038/ncomms12436. [Epub ahead of print]