Figure 1: HMGB3 depletion increases cisplatin sensitivity in cisplatin-resistant human ovarian cancer cells.

A, Clonogenic survival of U2OS cells, treated with psoralen and 1.8 J/cm² UVA (365 nm) to induce ICLs, as a function of HMGB protein depletion. NTC=non-treated control, NSsi=non-specific siRNA, HMGB1–3=specific siRNAs against each protein as listed. B, Alteration of the HMGB genes. Red represents gene amplification, blue represents deletions, and green represents point mutations. C, Schematic outline of the siRNA treatment and clonogenic survival assay along with siRNA-mediated depletion of HMGB3 in A2780/CP70 cells, evaluated by western blot analysis. On average, ~90% HMGB3 depletion was detected from 3 independent experiments. KD refers to knockdown. NT refers to cells treated with non-targeting siRNA (Mock KD). D, Colony formation was evaluated using a clonogenic assay and visualized by fixing the cells with 95% alcohol and staining with 0.05% crystal violet. Various treatments are listed on the right side of the panel. The bar graph represents quantification of colony numbers from three independent experiments. Error bars represent ± SD. The p-values were determined via t test and p-values of 0.05 or lower were considered significant.