CLDN15 and cancer: Additionally, cluster SPSB4 KCTD6 COMMD5 is involved in neddylation, CLDN12 CLDN15 cluster is involved in calcium-independent cell–cell adhesion via plasma membrane cell-adhesion molecules, tight junction interactions, and epithelial-to-mesenchymal transition in cancer, and CTSB M6PR is involved in lysosome activity.