The human cholinergic neuroepithelioma cell line SK-N-MCIXC, which expresses high levels of cholecystokinin (CCK) mRNA and secretes intact CCK into the media, was used to examine CCK processing and metabolism.
However, we have used a radioimmunoassay that detects the CCK precursor to demonstrate synthesis of CCK precursor-like peptides by all of the Ewing sarcoma and neuroepithelioma lines that were tested and by the rhabdomyosarcoma cell line that expresses CCK mRNA.
In contrast, the cholecystokinin (CCK) gene which is widely present in nervous and endocrine systems was abundantly expressed in the human primitive neuroepithelioma cell line SK-N-MC and its clonal derivative SK-N-MC-IX-C.
The human small-cell lung carcinoma line (SCLC) U-1690 expressed moderate levels of CCK mRNA as compared to the human neuroepithelioma cell line SK-N-MC.
The cholecystokinin gene is abundantly co-expressed with gastrin-releasing peptide, enkephalin and neuropeptide Y genes in a clonal human neuroepithelioma cell line.