Further research discovered that HER2 gene amplification might govern the generation of invasive pseudopods by activating the WAVE2-Arp2/3 signaling pathway, which in turn increased MMP-independent breast cancer cell invasion and migration.[56] In another study, Ko et al[57] found that inhibiting the Rac1/WAVE2/Arp2/3 pathway with pterostilbene greatly reduced the invasion and migration of MDAMB-231 breast cancer cells without causing cytotoxicity. This evidence concerns the gene ERBB2 and breast cancer.