Fig. 4

Potential molecular mechanism of lysosomal membrane hyperpermeability induced by PPT1 inhibitor. A Fluorescence images of acridine orange staining in HCC cells treated with DC661 (3 µM, 6 h). Hoechst 33,258 staining marks the nuclei. Scale bar, 50 μm. B Gene correlation analysis using TCGA dataset. Heat map of the correlation between multiple genes and one gene. PPT1 expression was positively correlated with HSP70.1 and BMP expression in HCC (linear regression); **P < 0.01. C Immunofluorescent staining of HSP70.1 in HCC cells treated with DC661 (3 µM, 6 h). Scale bar, 10 μm. D Semiquantitative analysis of the mean fluorescence intensity (MFI) in HCC cells according to (C) was performed by using ImageJ software (n = 6). Data represent mean ± SD; *P < 0.05. E Gene correlation analysis using TCGA dataset. PPT1 expression was positively correlated with HSF1 and calpain expression in HCC (linear regression); P < 0.001. F Gene correlation analysis using TCGA dataset. PPT1 expression was positively correlated with EP300 and mTOR expression in HCC (linear regression); P < 0.001. G Schematic illustration of a potential molecular mechanism of lysosomal membrane hyperpermeability induced by PPT1 inhibitor. HSE: heat shock element