Fig. 7: TOPORS-editing sensitizes cells to HMA in a DNMT1-dependent manner.

A (left axis) Survival of polyclonally gene-edited or wild-type MDS-L cells cultured in 96-well plates in response to daily doses of the DNMTi GSK3685032 or vehicle on days 1–4. (left axis) tagRFP⁺ cells (or all cells for wild-type MDS-L) were counted on day 5 and normalized to vehicle counts; n = 3 technical replicate culture wells per data point. (right axis) In a separate experiment, relative demethylation of LINE-1 promoters in wild-type MDS-L was determined (see “Methods”) for a similar GSK3685032 dose range and normalized to vehicle control cells; n = 3 technical replicate culture wells per data point. B Polyclonally gene-edited MDS-L cells were plated into 96-well plates and treated with 1 µM GSK3685032 or vehicle on day 1. Varying DAC plus 1 µM GSK3685032 or vehicle was added daily on days 2–4, and tagRFP⁺ cells counted on day 5, and normalized to vehicle counts. C, D Polyclonally gene-edited MDS-L cells were plated into 96-well plates and treated on day 1 only with (C) Topotecan or (D) Etoposide or vehicle. Absorbance at 490 nm was measured in MTS assays on day 5 and normalized to vehicle. E Polyclonally gene-edited MDS-L cells in 96-well plates were treated with daily Hydroxyurea or vehicle on days 1–4. tagRFP⁺ cells were counted on day 5 and normalized to vehicle counts. In all panels, dots represent mean ± SD, (A, B) n = 3 technical replicate cultures per data point, (C–E) n = 4 technical replicate cultures per data point. EC50 values deduced from all panels are shown in Table S2. Each experiment was performed once. Source data are provided as a Source Data file.