TFF1 and breast cancer: Meanwhile, we discovered the host gene of circ‐TFF1, TFF1, was also highly expressed in breast cancer tissues, in accordance with previous researches that TFF1 was specifically found to be elevated and promoted the development of breast cancer.14, 15, 27 Besides, we uncovered that TFF1 expression was positively associated with circ‐TFF1 expression in breast cancer tissues.