Interestingly, when cells were washed after 3 days of treatment with HMGB1-fl or HMGB1-ΔC and then cultured for 3 additional days in a HMGB1-free medium, the effect of the two proteins on the tumor cells growth was abolished (Figure 3, dashed lines), suggesting that both full-length and truncated forms of HMGB1 required a continuous exposure time to optimally exert their anti-proliferative activities. Here, HMGB1 is linked to neoplasm.