Varying Opinions on the Authenticity of a Human Midgut Carcinoid Cell Line – Letter

In 2007, our laboratory published an article in Clinical Cancer Research reporting on the development of a human midgut carcinoid tumor cell line (1). This cell line has now been shared with over 20 laboratories around the world. Investigators in the field of neuroendocrine tumor research are aware that there are very few human carcinoid cell lines available for use in vitro and for murine studies. At the time of publication of this article, we believed that we had developed the first human midgut carcinoid cell line in North America. These cells expressed dense neurosecretory granules on electron microscopy, VMAT-1/2, and somatostatin receptors (1). Recently, we performed short tandem repeat genotyping of the CNDT cell line, and we were unable to match this cell line to any other cell line in our own database at M.D. Anderson Cancer Center, The John Hopkins database, or the American Type Culture Collection database. This, in some ways, was reassuring as these databases contain data on thousands of cell lines, and we could rule out contamination of our CNDT2 cells by other well-characterized cell lines. However, we then tried to match our cell line with frozen carcinoid specimens in our tissue bank, and unfortunately, we were unable to match our short tandem repeat genotype to the carcinoid tumor that we thought was the source of this cell line. The short tandem repeat data for CNDT2 is listed in Table 1 below:Several investigators who have obtained this cell line have questioned the authenticity of its neuroendocrine background. At the Carcinoid and Neuroendocrine Tumor Scientific Forum 2010, a joint conference sponsored by the Verto Institute, The Raymond and Beverly Sackler Foundation, and The Caring for Carcinoid Foundation, held in Boston, MA, May 7, 2010, there were mixed opinions on the neuroendocrine tumor origin of this cell line, as summarized below. Some of these findings were in contrast with our own findings, whereas other observations were unique from those found in our studies.Researchers are advised to keep in mind the questions and skepticism of investigators in the field regarding the neuroendocrine authenticity of this cell line when reading articles that report on its use.No potential conflicts of interest were disclosed.