PCA3 and atypical carcinoid tumor: LncRNA-p21 is highly expressed in neuroendocrine prostate cancer patients and cells [86] while MEG3 and prostate cancer antigen 3 (PCA3) were aberrantly expressed in pulmonary NENs, including typical carcinoid tumors, atypical carcinoid tumors, small cell lung carcinoma (SCLC/NEC) and large cell neuroendocrine carcinoma (LCNEC/NEC) [59].