Fig. 6: Deletion of Tspan8 expression in the HR- luminal cells render Brca2^mut/WT organoids incapable of recovery from DNA damage.

A Dot plot showing the expression selected HR- luminal expressed marker genes upregulated or downregulated in Brca2^mut/WT P4 HU-treated organoids compared to the other groups. Circle size indicates the percentage of cells in which the gene expression was detected. Fill colour depicts the normalised and scaled mean expression level. B UMAP with overlaid expression of Tspan8 gene (purple) from control or HU-treated passage 4 wild-type or Brca2^mut/WT organoids. C Quantification of the percentage of Tspan8+ cells in the luminal progenitor population over different passages (P0, P2 and P4) from wild-type or Brca2^mut/WT organoids treated with HU. Data presented as the mean +/− SD (n = 7). A two-way ANOVA followed by a Fishers LSD test was performed. D Representative flow cytometry analysis of Tspan8 expression from control (upper) or Tspan8-knockout (ko, lower) wild-type and Brca2^mut/WT organoids. E Quantification of the percentage of epithelial cell types from control or Tspan8 KO wild-type or Brca2^mut/WT organoids. Data presented mean +/− SD (n = 3). A two-way ANOVA followed by a Fishers LSD test, Brca2^mut/WT Tspan8 KO CD49b+ *P = 0.0441, Brca2^mut/WT Tspan8 KO Sca1+ *P = 0.0206. F Representative brightfield images of Brca2^mut/WT organoids derived from control or Tspan8 KO cells at passage 3 after 4 intermittent HU treatments (left). Scale bar = 800 μm. Quantification (right) of the number of wild-type or Brca2^mut/WT organoids from control and Tspan8 KO post HU treatments at passage 3. Data presented mean +/− SEM (n = 3). A two-way ANOVA followed by a Tukey’s multiple comparison test, ***P < 0.001. Source data are provided as a Source Data file.