Combretastatin A-4 inhibits cell growth and metastasis in bladder cancer cells and retards tumour growth in a murine orthotopic bladder tumour model
作者:Cheng-Huang Shen、Jia-Jen Shee、Jin-Yi Wu、Yi-Wen Lin、Jiann-Der Wu、Yi-Wen Liu
DOI:10.1111/j.1476-5381.2010.00861.x
日期:2010.8
BACKGROUND AND PURPOSEBladder cancer is a highly recurrent cancer after intravesical therapy, so new drugs are needed to treat this cancer. Hence, we investigated the anti‐cancer activity of combretastatin A‐4 (CA‐4), an anti‐tubulin agent, in human bladder cancer cells and in a murine orthotopic bladder tumour model.EXPERIMENTAL APPROACHCytotoxicity of CA‐4 was measured by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay, propidium iodide (PI) staining assay and clonogenic survival assay. In vivo microtubule assembly assay, cell cycle analyses, Western blot and cell migration assay were used to study the mechanism of CA‐4. The effect of intravesical CA‐4 therapy on the development of tumours was studied in the murine orthotopic bladder tumour model.KEY RESULTSCA‐4 inhibited microtubule polymerization in vivo. Cytotoxic IC50 values of CA‐4 in human bladder cancer cells were below 4 nM. Analyses of cell‐cycle distribution showed CA‐4 obviously induced G2‐M phase arrest with sub‐G1 formation. The analyses of apoptosis showed that CA‐4 induced caspase‐3 activation and decreased BubR1 and Bub3 in cancer cells. In addition to apoptosis, CA‐4 was also found to induce the formation of multinucleated cells. CA‐4 had a significantly reduced cell migration in vitro. Importantly, the in vivo study revealed that intravesical CA‐4 therapy retarded the development of murine bladder tumours.CONCLUSIONS AND IMPLICATIONSThese data demonstrate that CA‐4 kills bladder cancer cells by inducing apoptosis and mitotic catastrophe. It inhibited cell migration in vitro and tumour growth in vivo. Hence, CA‐4 intravesical therapy could provide another strategy for treating superficial bladder cancers.