Tiny non-coding bits of RNA could hold the key to identifying malignant mesothelioma earlier and potentially improving mesothelioma survival. That finding comes from a team of cancer researchers in Ancona, Italy.
A microRNA (miRNA) is a small part of an RNA molecule. Containing about 22 nucleotides, miRNAs play a key role in the regulation of gene expression in cells, including mesothelioma cells. This makes them prime candidates for use as mesothelioma biomarkers.
MiRNAs as Mesothelioma Biomarkers
Mesothelioma biomarkers are biological signposts found in tissue, blood, lung fluid, etc., that clinicians can use to guide them in treating mesothelioma patients and predicting mesothelioma outcomes.
Recently, a group of scientists in Italy combed the scientific literature to find the miRNAs most closely associated with asbestos exposure and with malignant mesothelioma.
The team identified a pool of miRNAs found in the blood and tissues of mesothelioma patients that have “biomarker potential” for mesothelioma. They called miRNAs in this group “mesomiRs”.
Testing the Potential of “MesomiRs”
Using the pool of mesomiRs as their starting point, the team identified the ones that they deemed the most promising candidates for diagnosing mesothelioma, particularly when used in combination with the biomarker protein mesothelin.
“The qualitative meta-analysis and functional investigation confirmed the early diagnostic value of two miRNA signatures for malignant mesothelioma,” writes lead study author Luigina Micolucci with the Universita Politecnica delle Marche.
The team recommends that these miRNAs, which they say provide a “diagnostic signature” for mesothelioma, be subjected to further study, not only as diagnostic tools, but also as possible therapeutic targets.
“Large-scale, standardized validation studies are needed to assess their clinical relevance, so as to move from the workbench to the clinic,” states the report in Oncotarget.
In the meantime, the protein mesothelin remains the primary biomarker for diagnosing malignant mesothelioma.
In addition to mesothelin and miRNAs, other recently identified mesothelioma biomarkers with prognostic potential include neutrophil to lymphocyte ratio, (a measure of how well the immune system is functioning), c-MET expression (associated with blood vessel formation for the tumor), ki-67 ratios (associated with cancer cell proliferation), and levels of a protein called fibulin-3.
Minolucci, L, et al, “Diagnostic valu eof micoRNAs in asbestos exposure and malignant mesothelioma: systematic review and qualitative meta-analysis”, June 1, 2016, Oncotarget, Epub ahead of print