Evaluation of Cytotoxicity of Gold Glyconanoparticles of Human Colon Adenocarcinoma Cells

INTRODUCTION: Use of metal nanoparticles is a promising trend in oncotherapy.

AIM: To evaluate cytotoxicity of gold nanoparticles (GNPs) modified with fucose, lactose and galactose residues, on Caco-2 cells.

MATERIALS AND METHODS: Cells were cultured to a monolayer with GHPs in concentrations of 10 µg/ml–600 µg/ml for particles with fucose, 10 µg/ml–900 µg/ml for particles with lactose and 10 µg/ml–550 µg/ml for particles with galactose. As non-tumor cells, Caco-2 cells were used after differentiation into small-intestine enterocytes (incubation time — 21 days). The cytotoxicity of GNPs was evaluated in MTT-test after incubation with cells for 2 hours, 8 hours and 24 hours. A comparison drug was fluorouracil in concentrations of 50 µg/ml–2000 µg/ml. The half-maximal inhibitory concentration (IC₅₀) was calculated in GraphPad Prism 8.4.3 program.

RESULTS: IC₅₀ for GNPs with fucose for tumor cells was 582 ± 29 and 336 ± 36 µg/ml after incubation for 2 hours and 8 hours, respectively; for GNPs with lactose — 769 ± 50 and 515 ± 45 µg/ml, for GNPs with galactose — 467 ± 299 and 299 ± 28 µg/ml. For differentiated cells, IC₅₀ for all types of GNPs was higher than for tumor cells after incubation for 2 and 8 hours: for particles with fucose — 530 ± 3 and 410 ± 15 µg/ml; for particles with lactose — 831 ± 7 and 639 ± 14 µg/ml; for particles with galactose — 511 ± 21 (p = 0.018) and 376 ± 36 µg/ml, respectively. After 24-hour incubation of Caco-2 cells with fucose, IC50 did not differ for tumor and differentiated varieties. For other GNPs, IC₅₀ for tumor cells was higher than for differentiated cells. Fluorouracil showed cytotoxicity for tumor cells with IC₅₀ 2108 ± 19 and 1764 ± 193 µg/ml after 2 hours and 8 hours of incubation, respectively. For differentiated cells, IC₅₀ of fluorouracil was 1694 ± 102 µg/ml after 2-hour incubation and 1694 ± 102 µg/ml after 8-hour incubation. There were no differences between IC₅₀ of fluorouracil for differentiated and tumor cells with equal incubation time.

CONCLUSION: GNPs with fucose, lactose and galactose have a cytotoxic effect on human colon adenocarcinoma cells and in the activity are superior to fluorouracil.