Fig. 4: Cytotoxicity and selectivity of the quadruple-conjugated C-dot nanomodel in high-grade glioma cell lines.

Brain tumor cell lines SJ-GBM2 (A). U87 (B) and NP53 (C) were treated with the single peptide conjugates; C-dots-shpep1-epi-AIC and C-dots-lnpep1-epi-AIC, and the quadruple nanomodel at concentrations shown, and viability assessed 72 h later. *p < 0.05 quadruple nanomodel vs. shpep1 single peptide conjugate. #p < 0.05 quadruple nanomodel vs. lnpep1 single peptide conjugate. n = 3 (0.05 µM), n = 4 (0.1 and 1 µM), n = 6 (5 µM) biologically independent experiments). D Cell viability of non-cancer cell line, VSMC, in response to treatment with the quadruple nanomodel. (n = 3 biologically independent experiments) For A–D, data is presented as percent viability relative to non-treated controls. E Cells were treated with concentrations ranging from 0.01 to 10 µM and IC₅₀ values determined. IC₅₀ values of single peptides conjugates and quadruple nanomodel for U87, SJ-GBM2 and NP53 cells, n = 6 biologically independent experiments; IC₅₀ value of the quadruple nanomodel for VSMC, n = 3 biologically independent experiments. IC₅₀ values for each cell line were compared using one-way ANOVA with post-hoc Tukey Test. For U87 cells, one-way ANOVA revealed a significant effect of treatment [F(2, 15) = 13.41, p = 0.0005, η² = 0.641] followed by Tukey’s HSD post-hoc test: a p = 0.001, b p = 0.002. For SJ-GBM2 cells one-way ANOVA revealed a significant effect of treatment [F(2, 15) = 10.68, p = 0.0013, η² = 0.59] followed by Tukey’s HSD post-hoc test: c p = 0.0022, d p = 0.0047. For NP53, p values were not significant. Next, we compared the quadruple IC₅₀ values across all the cell lines treated. One-way ANOVA revealed significant differences among treatments (F(3, 18) = 244.53, p = 8.99 × 10⁻¹⁵, η² = 0.98), followed by Tukey’s HSD post-hoc test: e, f and g p = 0.001. All graphs were generated in GraphPad Prism; error bars represent SEM; each biological replicate data point is shown.