Chen et al revealed that knockdown of SNHG15 suppressed cell proliferation and invasion and induced a strong apoptotic response in GC cells.40 Additionally, SNHG15 amplification could promote GC cell proliferation and invasion and largely increase the expression level of matrix metallopeptidase 2 (MMP2) and matrix metallopeptidase 9 (MMP9) at protein levels.40 These results showed that elevated expression of SNHG15 could facilitate GC development and progression partly through modulating MMP2 and MMP9.40 However, the molecular mechanism between SNHG15 and MMP2/MMP9 is not clear. Here, MMP9 is linked to gastric cancer.