Fig. 2

Riboflavin significantly accumulates in bronchial carcinoid spheroids. a Monolayer grown H727 and H720 cell lines and 3rd generation cultured spheroids were incubated with riboflavin, a marker for stemness, and uptake visualized by fluorescence microscopy. Autofluorescence images were captured. b Autofluorescence indicating riboflavin uptake mainly in the nucleus was quantified and shown as a percentage. Experiments conducted in triplicates