Telomerase Activity And Sialic Acid Levels In Human Glioma Cell Lines Insan Glioma Hücre Dizilerinde Telomeraz Aktivitesi ve Siyalik Asit

Objective: The telomerase enzyme complex comprises among other proteins, two main subunits; TERT and TR component. Polysialic acid chains modify the adhesive function of NCAM molecules, presumably by making it easier to relinquish the cells to which they are stuck. Telomerase activity and sialic acid levels may be used to predict the biological behavior of gliomas. Materials and Methods: Telomerase activity and sialic acid levels were investigated in the cell extracts taken from human glioma cell lines. To detect telomerase activity, telomeric repeat amplification protocol was performed. To examine sialic acid levels, a Sialic Acid Quantification Kit was used. The expression of hTERT, hTR and GAPDH in cell line, respectively, was analyzed by using a RT-PCR kit. Cells fixed on the flask base were used for NCAM through the streptavidin-biotinperoxidase staining method. Results: Telomerase activity was found to be increased in the later passages of human glioma cells, although it demonstrated a fluctuating pattern. Telomerase RNA and TERT expression were positive in all passages. Sialic acid levels were also seen to be increased, showing regular rising in the consecutive passages of human glioma cell line. Immuno-staining of the NCAM molecule was positive. Conclusion: The telomerase activity, which has been initially expected to increase in the proceeding passages, was increased by manifesting undulation. Besides, the fact that sialic acid levels showed a regular increase gradually in the proceeding passages of the glioma cell line may indicate that this increase is more regular than that of the telomerase activity.