Abstract
Purpose:
Until now only limited information about cultivated tumor initiating cells out of squamous cell carcinoma (SCC) from the human bulbar conjunctiva are available. Therefore, the establishment of a model cell line would be a useful tool for further studies. In particular, the phenotypic and molecular characterization in comparison to other SCC cells is of high interest. This would enable the development of new treatment options for clinical application.
Methods:
Epithelial cells were isolated from a bulbar conjunctival SCC obtained from a 74 year old male and were named PeCa-UkHb-01. For receiving a pure cell culture, epithelial cells were harvested by stepwise trypsinisation. Furthermore, mycoplasma contamination was tested. Cell doubling time and number of passages were determined. STR (short tandem repeats) and karyotype analyses were performed to verify the origin of the cells and to analyze chromosomal heterogeneity. For further characterization semiquantitative real-time PCR and immunofluorescence staining were carried out to detect tumor and epithelial progenitor cell markers. Spheroid and colony forming ability were performed.
Results:
The morphology of the new cell line resembled other epithelial SCC cell lines, furthermore STR experiments confirmed the origin of the cells from the donor. The cells were free of mycoplasma. They grew above passage number forty and could be frozen and recultured. Karyotype analyses revealed a heterogeneous composition of the cell culture and the karyogram itself showed aberrations and changes in the chromosome numbers. PeCa-UkHb-01 cells were able to build colonies and spheroids. Semiquantitative real-time PCR results displayed an upregulation of SOX2 in comparison with A-431 SCC cells. Furthermore the cells showed expression of the putitative ocular surface stem cell markers ABCG2, c Myc, Lin28, Oct4, P63, which indicates stem-cell like characteristics.
Conclusions:
PeCa-UkHb-01 cells fulfill the criteria of a cell line which might display characteristics of cancer stem cells. They showed similarities to established cell lines from SCCs and other tumors. Further characterizations are needed to confirm the hint of stem cell characteristics. This cell line will be a huge advantage for further basic research and development of therapeutic applications due to the fact that it is the first of its kind.
Keywords: 474 conjunctiva •
744 tumors