The chloride channel appendage CLCA gene is involved in a variety of biological processes, including cell differentiation, adhesion, apoptosis, and airway inflammation, with CLCA 2 responsible for mediating tumor cell invasion and the absence of CLCA2 promoting the transformation of epithelial cells into mesenchymal cells, suggesting a higher chance of cancer metastasis [76]. This evidence concerns the gene CLCA2 and neoplasm.