In a recent study, the up-regulation of six fibrogenic genes (COL5A2, COL1A2, COL3A1, ITGA5, ITGB1, and ITGB1) in pulmonary neuroendocrine carcinoma and the down-regulation of pulmonary neuroendocrine neoplasms were strongly related to no metastasis and overall survival [41]. Here, COL3A1 is linked to lung neuroendocrine neoplasm.