We examined the functional role of
clusterin in
chemotherapy-induced apoptosis and tested whether anti-sense transfection targeted against
clusterin enhances the chemosensitivity in human
bladder cancer cells in vitro.
Clusterin mRNA and
protein expression of 253J cells, a human bladder
carcinoma cell line,
after treatment with
cisplatin were measured by RT-PCR and Western blot analysis.
Clusterin expression and cell growth were compared between 253J cells transfected with constructed a
clusterin anti-sense plasmid vector (pCR-CLU-AS) and controls.
Tumor cell viability was measured with MTT assay after
cisplatin treatment. DNA fragmentation and CPP32 assay were performed.
Clusterin expression was increased
after treatment with
cisplatin and highest at 8 h in 253J cells.
Clusterin anti-sense transfectants were highly sensitive to apoptotic cell death induced by
cisplatin compared with parental 253J cells or control transfectants. Collectively, our results showed that expression of
clusterin was increased in the acute phase of cell death caused by
cisplatin and that suppressing the expression of
clusterin enhanced the susceptibility of apoptosis caused by
cisplatin in human
bladder cancer cells. These results suggest that lowering the expression of
clusterin might increase the sensitivity of
bladder cancer cells to chemotherapeutic agents.