PDE8A and pachyonychia congenita: Furthermore, lncRNA Sox2ot was overexpressed and was correlated with the tumor-node-metastasis (TNM) stage and overall survival rate in PDAC patients, and its levels decreased after tumor resection.73 In addition to identifying this lncRNA, this group identified a role of circRNAs in PC development, showing that high expression of a circRNA (circ-PDE8A) is correlated with lymphatic invasion, advanced TNM stage, and a poor survival rate in PDAC patients.