Anticancer activity, hTERT expression and telomere length analysis in SH-SY5Y neuroblastoma cell lines applied to docetaxel

Abstract

Neuroblastoma is the most common extracranial solid tumor of infancy in a broad range of clinical courses, ranging from spontaneous regression to fatal progression. Telomere maintenance plays an important role in genome stability and cell proliferation. Telomerase reverse transcriptase (hTERT in humans) is a catalytic subunit of the enzyme telomerase. In this study, it was aimed to determine the anticancer activity of the docetaxel chemotherapeutic agent in neuroblastoma cell line (SH-SY5Y) and to investigate its effect on hTERT gene expression level and telomere length. Molecular docking studies were performed on docetaxel with the crystal structure of telomerase. The electronic properties of docetaxel were calculated using the density functional theory (DFT) method. SH-SY5Y cells were treated for 24, 48 and 72 h with specific concentrations of docetaxel drug ranging from 1 to 100 µg/ml. IC50 doses of docetaxel were determined and administered to SH-SY5Y cells, followed by RNA isolation. hTERT and MYC gene expression levels and telomere length were measured in the docetaxel-treated sample using the RT-PCR method. In addition, theoretical analyzes were made. The IC50 values of docetaxel after 24, 48 and 72 h were 8.32±1.45 μg/ml, 7.67±2.56 μg/ml and 5.51±1.24 μg/ml, respectively. According to the results obtained, docetaxel was found to have the highest activity in 72 h of incubation. It was determined that the docetaxel drug decreased the expression level of the hTERT gene in SH-SY5Y cells. Telomere lengths were significantly reduced in the docetaxel treated SH-SY5Y cell line compared to the control group (p < 0.05). Molecular docking analysis results were in agreement with the experiments. Analysis results indicated a good interaction between docetaxel and the active site of telomerase. The results of this study, reinforced by molecular docking analyzes, might be proved valuable for the development of potent telomerase inhibitors.