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Establishment and Characterization of Two New Rectal Neuroendocrine Cell Carcinoma Cell Lines

Background: Human colorectal neuroendocrine cell carcinoma (NEC) is a rare disease with a poor prognosis. The biological behavior of NEC remains poorly understood. Materials and Methods: We established two new NEC cell lines from a patient with rectal neuroendocrine carcinoma, NECS-P and NECS-L from the primary tumor and a liver metastasis, respectively. We investigated the biological differences between the two cell lines to study the mechanisms involved in liver metastasis. Results: There was no difference between NECS-P and NECS-L in the morphological, ultrastructural and immunohistochemical studies. After addition of TGF-β1, the doubling times of NECS-P were increased in a dose-dependent manner relative to untreated cells, whereas TGF-β1 had no effect on NECS-L. The attachment and chemotactic response of the two cell lines were not enhanced by TGF-β1. The invasive capacity and the production of matrix metalloproteinase-2 (MMP-2) were significantly increased only in NECS-L following the addition of TGF-β1. When anti-MMP-2 antibody was added to the medium with TGF-β1, NECS-L invasion was inhibited. Conclusion: It is considered that these differences are important to understand the mechanisms of liver metastasis of NEC.