MMP9 and cancer: To investigate the SNHG1 downstream effectors responsible for ISO suppression of human BMIBC cell invasion and cell anchorage-independent growth, we first analyzed the expression of MMP-2 and MMP-9, which are positive regulators of cancer invasion, and of PTEN, a tumor suppressor that negatively regulates cancer cell proliferation and growth [36], in 5637 cells after ISO treatment using Western blotting.