Engineered EVs were used to deliver the antitumor drug fluorouracil (5-FU) and miR-21 inhibitor oligonucleotides to colon cancer cells expressing human epidermal growth factor receptor-2 (HER2), which reversed the resistance of the cancer cells to 5-FU and enhanced antitumor cytotoxicity [142]. Here, ERBB2 is linked to cancer.