MicroRNAs(miRNAs)aresmallnon-codingRNAmoleculesthatplayacrucialroleinregulatinggeneexpressionatthepost-transcriptionallevel.Incancer,thebiogenesispathwaysofmiRNAsareoftendisrupted,leadingtoabnormalmiRNAexpressionprofilesthatcontributetotumorigenesis,metastasis,anddrugresistance.ThemiRNAbiogenesisprocessinvolvesmultiplesteps,includingtranscription,nuclearprocessingbyDrosha-DGCR8complex,exporttothecytoplasmviaExportin-5,andfurtherprocessingbyDicertogeneratematuremiRNAs.DysregulationatanyofthesestepscanresultinalteredmiRNAfunction.CancercellsfrequentlyexhibitmutationsorepigeneticchangesinkeycomponentsofthemiRNAbiogenesismachinery,suchasDrosha,DGCR8,Dicer,andExportin-5.Additionally,oncogenicsignalingpathwayscandirectlyinfluencemiRNAprocessing.Understandingthesedysregulatedbiogenesispathwaysprovidesvaluableinsightsintocancerbiologyandmayleadtothedevelopmentofnoveldiagnosticmarkersandtherapeutictargetsforcancertreatment.
