MRC1 and lung carcinoma: Signal transducer and activator of transcription 6 (STAT6) is an important member of the STAT family, which is of great significance in regulating cell differentiation and cytokine production.[43] Phosphorylation of STAT6 is crucial for M2 polarization and can regulate the transcription of M2‐related genes such as Mrc1, Arg1, and Ym1.[44] In addition, STAT6 also plays a key role in tumor development and was shown to promote lung cancer progression by triggering an IL‐4 positive feedback loop and increasing M2 myeloid cells.[45] STAT6 is also a promoter of PPAR‐γ transcription.