STAT3 and renal cell carcinoma: To induce macrophage polarization toward the M2 phenotype, renal cell carcinoma (RCC)-derived EVs containing lncARSR delivered to macrophages acted as competing endogenous RNA for the microRNAs miR-34/miR-449, thus increasing signal transducer and activator of transcription 3 (STAT3) expression as the primary type of signaling of macrophage polarization (88).