Generation of highly reproducible 3D lung tumor spheroids in culture.

A) Eight cell lines were monitored over six days for formation and growth of tumor spheroids. Bright field images were taken daily. Magnification: 2x objective, scan bar: 1mm. B) Total area (μm²) of the tumor spheroids at day three were measured using the Operetta imaging system. N is equal to two to five replicates. C) Cell viability was determined at day one and three in six of the eight cell lines by CellTiter-Glo Assay (Promega). N is equal to fourteen replicates.