The assessment of the cytotoxic activity of 2-(1,1-dimethyl-1H-benzo[e]indolin-2-yl)-5,6,7-trichloro-1,3-tropolone against the human glioblastoma U87 MG cell line

Purpose of the study. To study the cytotoxic effect of 2-(1,1-dimethyl-1H-benzo[e]indolin-2-yl)-5,6,7-trichloro-1,3-tropolone (JO-122 (2)) on the U87 MG cell line.

Materials and methods. The investigation of the cytotoxic effect of synthesized tropolone JO-122 (2) was performed using the standard MTT colorimetric assay on the human glioblastoma cell line U87 MG. Test substance samples were prepared by sequential twofold dilutions of the original stock solution with concentrations of 24 μM. Temozolomide was used as a reference drug, and its tested doses fell in the range of 250 to 0.4883 μM. Incubation time after the addition of the substances were 24, 48, and 72 hours. The statistical processing of the obtained data was carried out using Microsoft Excel 2013 and Statistica 10 software.

Results. The cytotoxic effect of 2-(1,1-dimethyl-1H-benzo[e]indolin-2-yl)-5,6,7-trichloro-1,3-tropolone on the U87 MG cell line was investigated in the study. The assessment of cytotoxicity showed that at all investigated doses of tropolone, there was a statistically significant inhibition of cell growth in the U87 MG cell line. After 24, 48, and 72 hours, the necessary minimum concentration of JO-122 (2) for suppressing tumor cell growth was 3 μM, 0.0469 μM, and 0.1875 μM, respectively.

The comparison drug showed less pronounced suppression of tumor cell growth compared to tropolone. For an incubation time of 24 hours, no significant decrease in cell viability was observed in any of the tested concentrations. The minimum concentration of Temozolomide required to inhibit U87 MG cell culture growth was obtained after 72 hours and was 3.9063 μM.

Conclusion. The conducted research demonstrated that both substances exhibited concentration-dependent toxicity towards the human glioblastoma cell line. However, tropolone JO-122 (2) showed a more pronounced ability to suppress the growth of the U87 MG cell line.

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