IL6 and neoplasm: In our study, according to the endogenous IL-6 level (Table 2, Supplementary Table S1, Figure3, Supplementary Figures S1 and S2), the BMSC-CM we used (Table 1, approximately 589pg/105 cells) can stimulate the invasion and STAT3 signalingpathway of Bel-7404 cells, but not HepG2 cells (Figures 2 and 6), furthersuggesting that the endogenous cytokine composition markedly affects cell responsesto tumor microenvironmental stimuli.