Fig. 3

Loss of galectin-3 (Gal3) leads to an increase of functional CSC abilities. a Breast cancer cells were seeded into sphere-formation assays (SFA). Loss of Gal3 correlates with the inherent SFA ability displayed as number of spheres per 1000 seeded cells (n = 3). b Aldefluor activity of the breast cancer cell lines GI-101A, GI-LM2, and GI-LM2G was determined by flow cytometry. Similar to (a), loss of Gal3 increased the percentage of Aldefluor^pos cells from 26.6 % (GI-101A) and 39.7 % (GI-LM2) to 72.8 % (GI-LM2G). c Drug resistance to the FAC regimen (5-fluorouracil (5-FU), doxorubicin (adriamycin), and cyclophosphamide) was evaluated in CD24^neg/CD44^pos CSCs of GI-LM2C and GI-LM2G by APO-BrDU TUNEL assay (detected by an Alexa Fluor™ 488 dye-labeled anti-BrdU antibody as shown on the y-axis). GI-LM2C undergo cell death upon treatment, whereas GI-LM2G are mostly resistant (83.0 % vs. 7.68 %). d Cell cycle distribution was carried out by propidium iodide staining of GI-LM2 (red, left panel) and GI-LM2G (green, right panel) and evaluated by flow cytometry. Numbers including standard deviations are shown in the table. e MTT proliferation assay of spheres of GI-LM2 (red) and GI-LM2G (green) over 3 days. The relative OD490 on day 1 was defined as the starting point. Experiments were repeated at least three times. The criteria for significance were p < 0.05 (*) and p < 0.01 (**)