Figure 6. Refinement of lead 67LR inhibitor NSC47924.

A. LR-293 cells were plated in LM-coated wells in the presence of the selected molecules, dissolved in DMSO at a concentration of 20 μM, DMSO was used as negative control (■). The attached cells were stained and the absorbance at 540 nm was measured. The values represent the mean ± SD of three experiments performed in triplicate. (*) p < 0.05, as determined by the Student's t test. Among the 19 small molecules tested, only eight compounds were able to inhibit LR-293 cell binding to LM and are shown in figure. B. LR-293 cell adhesion to LM (■) and FN (□), in the presence of 20 μM of inhibitory molecules or DMSO, as a negative control. The attached cells were stained and the absorbance at 540 nm was measured. The values represent the mean ± SD of three experiments performed in triplicate. (*) p < 0.05, as determined by the Student's t test. Only four compounds specifically decreased LR-293 cell binding to LM, without affecting cell adherence to FN and are shown in figure. C. r37LRP was placed for 1 hour at 37°C on LM-coated wells in the presence of NSC47924 and selected analogs at a concentration of 50 μM; DMSO (■), was used as a vehicle control. Bound r37LRP was revealed by anti-His-HRP and OPD staining; the absorbance at 490 nm was measured. r37LRP binding to BSA-coated wells was subtracted to obtain specific binding. Values represent the mean ± SD of three experiments carried out in triplicate; (*, P < 0.05; **, P < 0.01; ***, P < 0.001), as determined by the Student's t test.