To evaluate the roles of other RAB3 members in the chordoma stemness and tumorigenic functions, we found that RAB3A, RAB3C, and RAB3D regulated the proliferation of CH22 cells, whereas they did not control the expressions of stemness markers, such as TBXT, NANOG, OCT4 and SOX2 (Figure S6, Supporting Information). This evidence concerns the gene POU5F1 and chordoma.