Breast cancer metastasis is a complex and still weakly understood process that involves diverse cellular pathways. It accounts for the majority of deaths from breast cancer. Recently, microRNAs (miRNAs), small non-coding RNAs that regulate gene expression post-transcriptionally, have been shown to be involved in breast cancer metastasis. In particular, in a recent work it has been found that miR-429 may have a role in the inhibition of migration and invasion of breast cancer cells. Its target gene CRKL has been identified as a potential candidate. In this paper, by using systems biology tools we have shown that CRKL is involved in positive regulation of ERK1/2 signaling pathway and contribute to the regulation of LYN through a topological generalization of feed forward loop.