Numerous researches have verified the vital role of MMPs, MMP‐2 and MMP‐9 in particular, in promoting the membrane‐basement invasion of tumour cells.22, 23 Related to MMPs, the activation of PI3K/Akt pathway is crucial for the growth and survival of cancer cells and it plays a dominant role in regulating EMT and the following process of migration and invasion.24 As shown in Figure 3, various studies have evaluated the in vitro anti‐cancer property in multiple cancer cell lines. Here, MMP9 is linked to cancer.