Fig. 1

Nalbuphine selectively inhibits tumor cell proliferation. a, b MDA-MB-231 and MCF-7 cells were treated with the indicated concentration of nalbuphine (Nal) for the indicated times, and cell viability was measured using the MTT method (n = 3). c Colony formation of MDA-MB-231 cells treated with indicated concentration of Nal (n = 3). d Cell lines derived from various tumor types were treated with 100 μM nalbuphine for 48 h and cell viability was measured by MTT assay (n = 3). e MCF-10A and MCF-10F were treated with 100 μM nalbuphine for 48 h and cell viability was measured by MTT assay (n = 3). Data are presented as mean ± SEM. The p-value was determined by Student’s t-test (*p < 0.05, **p < 0.01, ***p < 0.001). See also Additional file 2: Figure S1