New biomarker to monitor skin cancer therapies
Merkel cell carcinoma is often treated with immune checkpoint inhibitors. This treatment method was awarded the Nobel Prize for Medicine in 2018 and is used successfully at University Hospital Essen. The carcinoma responds to treatment in around 40 to 60 percent of cases, especially if it is the first time the cancer has appeared. If the treatment is not successful, the patient has to have an operation and chemotherapy.
“We therefore looked for a biomarker that can be used to reliably assess the tumor burden throughout the course of the disease,” explains Professor Jürgen C. Becker, head of the DKTK Translational Skin Cancer Research (TSCR) department at UDE’s Center of Medical Biotechnology (ZMB). Eventually, after a long search, the scientists found the cf miR-375 molecule that is released into the blood in excessive amounts by Merkel cell tumor cells, among other things. “This means that a blood test can check whether a patient is likely to respond to treatment and identify any relapses at an early stage,” says Prof. Becker.
The use of microRNAs as biomarkers is already established, for instance in colon cancer and breast cancer. “We hope that this will be the case for miR-375 in the future as well,” says Professor Becker. “In any case, it is a useful tool for monitoring response to treatment. It also allows more accurate indication for PET-CT imaging.”
Fan et. al. Circulating Cell-Free miR-375 as Surrogate Marker of Tumor Burden in Merkel Cell Carcinoma. Clin Cancer Res. 2018 Dec 1;24(23):5873-5882. DOI: 10.1158/1078-0432.