To examine the expression of gal-1 in two subpopulations of lung adenocarcinoma cells, we performed Western blotting by using CD133+ and CD133− cancer cell lysates from different human patients, as shown in Fig. 2A, CD133+ cells express significantly higher gal-1 than CD133− cells from the same patient (gal-1 is highly upregulated in CD133+ cells in eight out of nine patients, while CD133+ cells derived from patient No. 6 only showed minor overexpression of gal-1). The gene discussed is PROM1; the disease is cancer.