And at the end of experiment, the xenograft cancer cells generated overexpression of piR-19166 of were stained by immunostaining of anti-CTTN anti-MT1-MMP, anti-MMP2 and anti-MMP9, which showed that the percentage of positive cells were much lower than blank control cells using BN-880a pathological image analysis system (Shanghai Hanfei Medical Instrument Co., Ltd., Shanghai, China) (Figure 9C, P < 0.01). The gene discussed is MMP9; the disease is cancer.