Cytogenetic characterization of the malignant primitive neuroectodermal SK-PN-DW tumor cell line.

Background: The SK-PN-DW cell line was established in 1979 and is commercially available. Despite the use of this cell line as an in vitro model for functional and therapeutic studies of malignant primitive neuroectodermal tumor (PNET), there is a lack of complete information about the genetic alterations that are present at the cytogenetic level. Thus, the current study aimed to characterize the cytogenetic profile of this cell line.

Methods: Routine G-banded chromosome analysis, fluorescence in situ hybridization, and oligonucleotide array comparative genomic hybridization assays were performed to characterize the chromosomal changes in this cell line.

Results: The G-banded karyotype analysis showed that the number of chromosomes in this cell line ranged between 36 and 41. Importantly, all cells displayed a loss of chromosomes Y, 11, 13, and 18. However, some cells showed an additional loss of chromosome 10. Additionally, the observed structural changes indicated: a) unbalanced translocation between chromosomes 1 and 7; b) translocation between chromosomes 11 and 22 at breakpoints 11q24 and 22q12, which is a classical translocation that is associated with Ewing sarcoma; c) a derivative chromosome due to a whole arm translocation between chromosomes 16 and 17 at likely breakpoints 16p10 and 17q10; and d) possible rearrangement in the short arm of chromosome 18. Moreover, a variable number of double minutes were also observed in each metaphase cell. Furthermore, the microarray assay results not only demonstrated genomic-wide chromosomal imbalance in this cell line and precisely placed chromosomal breakpoints on unbalanced, rearranged chromosomes, but also revealed information about subtle chromosomal changes and the chromosomal origin of double minutes. Finally, the fluorescence in situ hybridization assay confirmed the findings of the routine cytogenetic analysis and microarrays.

Conclusion: The accurate determination of the cytogenetic profile of the SK-PN-DW cell line is helpful in enabling the research community to utilize this cell line for future identity and comparability studies, in addition to demonstrating the utility of the complete cytogenetic profile, as a public resource.