CACSTL1 and thyroid gland papillary carcinoma: For instance, the lncRNA CASTL1 has been found to promote the CCDC6-RET fusion (RET/PTC1) that is frequently expressed in papillary thyroid carcinoma by facilitating chromosomal rearrangements; in tumors with the CCDC6-RET fusion, there is increased CASTL1 expression, demonstrating a potential mechanism for how lncRNA dysregulation might lead to formation of oncogenic mutations [99].