The in vivo xenograft experiments verified that ZF-598SKD significantly inhibits tumor growth of breast cancers with a long-term effect.255 Likewise, ATF-based SOX2 inhibition technology also shows impressive effect in growth suppression of SCC in lung and esophageal cancers.256 However, ZF-ATFs in most cases are delivered by virus, limiting its utility due to poor delivery efficiency and nonspecific nature of viral infections. Here, SOX2 is linked to breast cancer.