We next immunoblotted for the following proteins: Bcl‐2 and BAX, which are critical indicators used for detecting cell proliferation and apoptosis24, 25; MMP‐9, which plays a crucial role in tumour invasion and metastasis26; and cyclin D1, a key regulator of cell cycle transition from G1 to S phase.27 Our results showed that after HULC knockdown, BAX was up‐regulated, whereas Bcl‐2, MMP‐9, and cyclin D1 were down‐regulated (Figure 6B). The gene discussed is CCND1; the disease is neoplasm.