Extended Data Figure 7. Both sorted basal and sorted luminal cell populations are required to reconstitute biclonal tumors.

Chimeric tumor relapses generated by injecting iWnt/mRFP⁺ tumor cells onto cWnt rescue hosts were resolved into their component basal (mRFP⁺/HRas^mut/Wnt1^low) and luminal (mRFP⁻/HRas^wt/Wnt1^high) cell subsets by FACS. Each sorted population was injected separately (10⁵ basal cells/injection or 10⁵ luminal cells/injection) or as a 1:1 admixture (5×10⁴ basal cells + 5×10⁴ luminal cells/injection) onto wild-type, Dox-naïve hosts. All reconstituted tumors faithfully recapitulated the biclonal configuration of the source tumor. Depicted are FACS plots from parental and reconstituted tumors showing both mRFP⁺ and mRFP⁻ subclonal populations. Colors indicate events within the basal (blue; CD49fHigh/EpCAMlow) and luminal (green; CD49fLow/EpCAMhigh) gates. Percentages depict mean +/− SEM for n = 5 clonally related parental tumor outgrowths and n = 11 tumor outgrowths reconstituted from injection of admixed cells.