Well known differentiation marker analysis after IGFBP-rP1 transfection. The experiments were conducted in three colon cancer cell lines: RKO, SW620, CW2. The parental blank cells (-bl), PcDNA3.1 empty vector transfectants (-ev), and PcDNA3.1(IGFBP-rP1) transfectants (-rp), were cultured in DMEM medium. A:Total cell lysates and supernatants were harvested and assayed for alkaline phosphatase activity assessing. Results represent the mean (± SD) of three experiments.*p < 0.05. B. Total cell lysates were harvested and assayed for CEA, CDX2 expression. Also shown are the corresponding reprobings of these blots with actin as a loading control. This blot is representative of those obtained when the experiment was performed six times.