Effect of TCTP on the expression and secretion of HMGB1 in LoVo cells. (A) Immunofluorescence analysis of the expression of HMGB1 following modulation of the expression of TCTP in LoVo cells (magnification, ×400). Green, HMGB1; blue, nuclei; red, F-actin. (B) Immunoblotting analysis of the expression of HMGB1 in the cytoplasm and the culture medium of LoVo cells following modulation of the expression of TCTP. Values were normalized to the internal control GAPDH. **P<0.01, compared with LoVo-NC cells. Similar results were obtained in four independent experiments. (C) Measurement of extracellular LDH release from control LoVo cells or cells transfected with vectors. The results are expressed as a percentage relative to the control group. No significant difference was observed in LDH activity among the three cell lines. LoVo-NC, normal control LoVo cells; TCTP-K, LoVo cells transfected with TCTP-knockdown vector; TCTP-O, LoVo cells transfected with TCTP-overexpression vector; TCTP, translationally controlled tumor protein; HMGB1, high mobility group box 1; LDH, lactate dehydrogenase.