（2019-06-25，EH）

        Metastasis is the leading cause of cancer death. The Identification of new anti-metastasis drugs is critical for improving current cancer therapeutics. By analysing the mechanism of metastasis and EMT (epithelial-mesenchymal transition) pathways, we identified a key biomarker for metastasis. After many experiments and tests, we set up a powerful anti-metastasis drug screening system through combining the biomarker with a GFP-Luciferase reporting system. We knocked-in the reporter genes (GFP-Luciferase) into the biomarker gene to make a Biomarker-GFP-Luciferase fusion gene. The fusion gene was expected to express a Biomarker-GFP-Luciferase protein. Thus, we are able to detect the expression of the biomarker by measuring the GFP or luciferase expression. A higher level of GFP/luciferase indicates higher expression of the biomarker, while a lower level of GFP/luciferase means a lower expression of the biomarker. When the system is used to screen a compound library, a lower expression of the biomarker indicates that the cell mobility is inhibited by a corresponding compound.

      The Integra liquid dispenser (Switzerland) was used for aliquoting cells evenly into a 96-well plate. The machine can be manipulated for dispensing compounds, cell lysis buffer, and more.

       For detecting the expression of the GFP/luciferase, A PerkinElmer or a BioTek microplate reader was used to measure the fluorescence level.

       By comparing the fluorescence value of the treated cells with that of the negative and positive controls, we identified candidate anti-metastasis lead compounds. The candidates are subjected to in vitro and in vivo validation systems such as Wound-Healing Assay, Transwell Assay, Western Blot, and animal model tests.

      Currently, we have screened three compound libraries (Beijing University Compound Library, Sun Yat-Sen University Compound Library, and an FDA compound library) and identified 41 candidate anti-metastasis lead compounds. The vilidation process is going smoothly.