A molecular test for patients with metastatic colorectal cancer (mCRC) based on the miR-31-3p biomarker will allow for a more personalized approach to cancer care.

What is a micro-RNA?MiRNA

MicroRNAs (miRNA) are small 19 to 25 nucleotides, noncoding RNAs that negative regulate gene expression posttranscriptionally by inhibiting translation or degrading mRNAs. miRNAs control biologic processes such as cell proliferation, differentiation, angiogenesis, and apoptosis. miRNAs are involved in the occurrence of many types of cancer, including colorectal cancer.

Click here to learn more about the formation and function of miRNAs.

Why study miR-31-3p in colorectal cancer?

The discovery and development of the miR-31-3p biomarker for patients with metastatic colorectal cancer (mCRC) is based on original research led by Pierre Laurent-Puig, M.D., Ph.D., Professor, Department of Genetics and head of the Clinical Oncogenetic Unit, European Georges Pompidou Hospital, University Paris Descartes, Paris, France.

While anti-EGFR (epidermal growth factor receptor)  are not indicated for approximately 50% of mCRC patients since they carry a KRAS or NRAS mutations which makes them non-responsive to these agents, anti-EGFRs remain an option for RAS wild-type (WT) patients. Unfortunately, the response to these agents is variable in this patient population.

Clinical studies with miR-31-3p in Metastatic colorectal cancer

MiR 31 3p mCRC PFSClinical studies have demonstrated that the expression level of miR-31-3p in primary tumors of KRAS WT patients with mCRC predicts response to EGFR inhibitors. Determining the expression level of the miR-31-3p biomarker will allow for a more personalized approach to cancer care, sparing patients who would not likely benefit from anti-EGFR agents from therapy-associated toxicities while also preventing the loss of time and opportunity to receive other treatment options which may be more appropriate and reducing cost of care.

Click here to review the results of studies to date which have demonstrated the predictive effect miR-31-3p expression has on response to EGFR inhibitors in patients with mCRC.