['To study whether the infection of Schistosomiasis japanicum (S. japanicum) is related to enhanced proliferation and migration of cancer cells, and the molecular mechanism pertains to cancer cell metastasis in human host.', 'The gene of S. japanicum glutathione transferase (sjGST) cloned from S. japanicum was expressed, purified and applied in a series of assays to explore the effect of sjGST on proliferation and migration of MDA-MB-435S, and the expression of MMP2 and MMP9. Immunofluorescence assay for the binding of sjGST to MDA-MB-435S was also carried out.', 'Results showed that sjGST enhanced proliferation and migration in human breast cancer cell MDA-MB-435S signifycantly at 50-200 nM, but did not enhance them in human lung cancer cell A549. Immunofluorescence assay for the binding of sjGST to MDA-MB-435S and A549 showed that GST was readily bound to the breast cancer cells, but showed almost no binding to human lung cancer cells. The assays for gelatinase activity showed that both MMP2 and MMP9 activities were increased significantly in the presence of sjGST (50-200 nM) in MDA-MB-435S, but they were not significant in A549.'] Is infection of Schistosomiasis japanicum likely to enhance proliferation and migration of human breast cancer cells : mechanism of action of differential expression of MMP2 and MMP9?