What new method are you referring to? We like to screen miRNAs to evaluate potential beneficial effects on everything from tumor growth to protein expression, similar to siRNA screening (https://altogen.com/transfection-resource/sirna-library-screening/) which can give basically the same information. Choose a few cell lines and some miRNA sequences you're interested in, transfect them, and look at the results. There's a chance you could find something interesting.