BTG2/TIS21 enhanced DOXO-induced cell death in human cancer
cell lines. A, increase of chromatin condensation in HeLa cells
after treatment with DOXO and Ad-TIS21 virus. HeLa cells were infected with
adenoviral vector expressing HA-tagged BTG2/TIS21 (Ad-TIS21-HA) or
β-galactosidase (Ad-β-Gal) for 36 h and then treated with DMSO or
DOXO (1.0 μg/ml) for 12 h. Hoechst dye staining was performed, and the
cells with chromatin condensation were counted. ⋆, p < 0.05
versus DOXO and Ad-β-Gal treated cells; #, p < 0.05
versus DOXO and Ad-BTG2/TIS21 (10 m.o.i.)-treated cells.
The data represent the means and standard deviation from four independent
experiments. B, Western blot analysis showing the increased cleavage
of PARP and lamin A/C in HeLa cells after infection with Ad-TIS21 virus (50
m.o.i.) compared with the cells treated with DOXO alone or DMSO for 12 h.
Anti-HA shows the level of TIS21 expression. C, inhibition of
DOXO-induced cell death by lentivirus infection containing short hairpin-BTG2
sequences. HeLa cells were infected either with empty vector (Con) or
sh-BTG2 virus (H4 and H5), and knockdown of BTG2 expression
and the accompanying inhibition of cell death were examined then by RT-PCR and
Western blot analyses, respectively. RT-PCR analysis of the level of BTG2 mRNA
was normalized to the level of glyceraldehyde-3-phosphate dehydrogenase mRNA,
and the level was indicated at the bottom of the data. Note inhibition of BTG2
expression by sh-RNA (H5) more than 60%. D, enhanced cell death by
Ad-TIS21 infection in liver cancer cells. Huh7, HepG2, and Hep3B cells were
infected with Ad-TIS21 virus and then treated with either DMSO or DOXO (1.0
μg/ml) for 36 h. The cleavages of PARP and lamin A/C were examined by
Western blotting. Note the increase of PARP and lamin A/C cleavages. The data
represent a typical result from four independent experiments.