(A) MCF10A cells expressing 6 genes WHSC1L1, BRF2, DDHD2, PROSC, ERLIN2 and ASH2L formed expanding colonies in insulin-free medium, while MCF10A cells expressing HOOK3 and control LacZ did not form colonies. (B) In vitro growth rate of the MCF10A cells that stably over express the 5 genes (ERLIN2, WHSC1L1, DDHD2, PROSC and BRF2) relative to MCF10A-LacZ control cells in insulin deficient media. Cells were seeded into 35-mm culture wells and grown in the absence of insulin-like growth factors.