ERBB2 and cancer: Moreover, human epidermal growth factor receptor 2 (HER2) signaling activates the transcription of mir-21, which is further stabilized by miR-4728-3p through the inhibition of TUT3/PAPD5/TENT4B [76], suggesting the significance of the non-canonical poly(A) polymerase TUT3/PAPD5/TENT4B pathway in cancer.