Establishment and genetic characterization of an immortal tumor cell line derived from intestinal-type sinonasal adenocarcinoma

Abstract

Intestinal-type sinonasal adenocarcinoma (ITAC) is a rare tumor etiologically related to professional exposure to wood dust. The overall prognosis is poor, mainly due to the difficulty to resect the tumor completely in this anatomically complex region. Therefore, there is great need for alternative treatments. However, the lack of a good tumor model system for ITAC has hampered the development and testing of new therapeutic agents. Here, we report the establishment and characterization of the first human ITAC cell line named ITAC-3. The cell line was initiated from small explants of a T4bN0M0 colonic type ITAC from the ethmoid sinus. Growth and invasion parameters as well as genetic characteristics were analyzed. The population doubling time was 18 h and the cell line was capable of invasion in matrigel. Chromosomal analysis showed a tetraploid karyotype with both numerical and structural aberrations. High resolution microarray CGH analysis identified many copy number alterations, including homozygous deletions. TP53 carried a mutation c.818G>T in exon eight concurring with a strong nuclear protein overexpression. Immunohistochemical analysis showed protein overexpression of EGFR and normal expression of β-catenin and p16. This is the first report of the establishment of a cell line derived from a primary ITAC. The genomic profile of the cell line was the same as the primary tumor from which it was derived. This new cell line will be a useful tool for the development and testing of new therapeutic agents for this tumor type.