However, several migratory and invasive cancerous cell types have been associated with high expression of claudin-1 including breast cancer, colon cancer, liver cancer, oral squamous carcinoma, and melanoma (Leotlela et al., 2007; Akasaka et al., 2010; Yoon et al., 2010; Blanchard et al., 2013). This evidence concerns the gene CLDN1 and breast cancer.