['To investigate the effect of small interfering RNA (siRNA)-mediated islet neogenesis associated protein (INGAP) gene silencing on the proliferation of islet cells.', 'Different siRNAs targeting INGAP gene were designed and transfected into INS-1 islet cells, and the expression levels of INGAP mRNA and protein following the transfection were detected using RT-PCR, flow cytometry and Western blotting. The proliferation of the transfected INS-1 cells was evaluated using MTT assay.', 'Compared with those in the irrelevant siRNA, empty vector control, and un-transfected groups, the expression levels of INGAP mRNA and protein in the cells transfected with siRNA6 were reduced significantly. The cell proliferation rate significantly increased after transfection with siRNA6 (P<0.05).'] Does [ Small interfering RNA-mediated islet neogenesis associated protein gene silencing inhibit the proliferation of INS-1 islet cells ]?