Objective To investigate the role of USP33 as an independent prognostic marker in the regulation of SLIT2/ROBO1 signaling pathway to inhibit lung adenocarcinoma invasion and metastasis. Methods The expression of USP33 in 20 lung adenocarcinoma specimens was detected by q PCR and immunohistochemistry. A549 and SPC-A-1 cells with small interfering RNA(si RNA)-mediated USP33 silencing were examined for changes in invasion and metastasis abilities using scratch assay and Matrigel assay. Western blotting was use...