In vitro cell viability assay. A. NCI-H82 small cell lung cancer cells (H82) and 3T3 fibroblasts (3T3) were plated at 2,000 cells/well. Pentastatin-1 peptide was applied at increasing concentrations up to 100 μg/mL, and incubated for three days. Cell viability was determined using the WST-1 colorimetric agent, and scaled to the untreated experimental control. Differences between H82 and 3T3 treatments are statistically significant as determined by the Student's t-test at p < 0.05 * and p < 0.01 **. B. BrdU incorporation for NCI-H82 small cell lung cancer cells and 3T3 fibroblasts. Cells were plated at 10,000 cells/well with pentastatin-1 at concentrations of 3.8, 15 and 60 μg/mL in the presence of a BrdU label for 24 hours. BrdU incorporation was detected by the BrdU-antibody peroxidase conjugate as a measurement for cell proliferation by DNA synthesis. Pentastatin-1 decreases cell proliferation by 50% for H82 and 33% for 3T3 at 60 μg/mL. Statistical significance is determined at p < 0.05 * and p < 0.01 ** by Student's t-test.