CLDN15 and breast cancer: CLDN15 has been shown to be a positive indicator associated with malignant pleural mesothelioma in clinical contexts (Watanabe et al., 2021), while CLDN16 is a predictor of oral squamous cell carcinoma, breast cancer, and thyroid cancer (Chen et al., 2010; Gomez-Rueda et al., 2016; Ribeiro et al., 2021).