Growth-promoting effect of transcription-involved protein upregulated in HCC (TIPUH1). (a) Anchorage-independent growth of NIH3T3-TIPUH1 cells in soft agar. The representative picture of NIH3T3-TIPUH1 cells expressing stably exogenous TIPUH1 (upper panel), and that of NIH3T3-mock cells (lower panel) were shown. The number of colonies was counted after 3 weeks of plating and shown in the histogram (right panel). *Significant difference (P<0.05) determined by a Student's t-test. (b) Gene-knockdown effect and growth-suppressive effect of plasmids expressing four different TIPUH1-siRNAs or EGFP-siRNA, and mock plasmid. Semiquantitative RT–PCR was carried out to examine expression of TIPUH1 48 h after transfection of the plasmids into HepG2 cells (lower panel). Viability of HepG2 cells transfected with the plasmids was analysed in triplicate by MTT assays on day 7 after transfection and subsequent maintenance of cells with an appropriate concentration of G418 (upper panel). (c–e) Growth-suppressive effect of TIPUH1-siRNA-02 in Huh7 (c), Alexander (d), and SNU449 cells (e). *Significant difference (P<0.05) determined by a Student's t-test.