VASP and non-small cell lung carcinoma: To investigate whether KHSRP, PSIP1 and VASP were involved in human NSCLC metastasis progress, siRNA was used to knock down the expression of these genes in A549 cell line (Additional file 1: Figure S3A), and then the in vitro invasion and migration abilities of cells transfected with siRNAs were evaluated using transwell assays (Additional file 1: Figure S3B).