Comparative Study of Apoptotic Antitumor Effect between Angiogenesis Inhibitor AGM-1470 and MVAC Chemotherapy on Rat Urinary Bladder Cancer

Abstract

Objectives: To investigate the antitumor apoptotic effect of AGM-1470 by comparing it to that induced by methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) therapy, currently the standard chemotherapy for bladder cancer, in a rat bladder cancer model. Materials and Methods: A total of 45 six-week-old female rats were divided into 3 equal groups: those receiving AGM-1470 treatment; those receiving MVAC treatment, and controls. All rats were cystectomized to evaluate the therapeutic effect with regard to macroscopic tumor findings, hematoxylin and eosin pathology, apoptosis detection, and immunohistochemistry (IHC) for bcl-2. Results: Our experimental protocol succeeded in producing invasive bladder tumors in the majority of rats. Tumor volume was significantly reduced in the AGM-1470 and MVAC treatment groups compared with that in the control group. The apoptotic indices of tumor cells was significantly higher in the AGM-1470 and MVAC treatment groups than in the control group. IHC for bcl-2 demonstrated no statistical difference in expression among the groups. However, the apoptotic indices of high-level bcl-2 expression were significantly lower than the indices of low-level expression in the AGM-1470 group. Conclusions: AGM-1470 and MVAC appear to exert a prominent mass reduction effect via tumor cell apoptosis in cases of invasive bladder tumor, although these therapies did not demonstrate any obvious modulation of bcl-2 protein expression status. Bcl-2 overexpression might be an obstacle to AGM-1470 therapy because of its significant inhibitory effect on apoptosis.

Vinblastine, a Chemotherapeutic Drug, Inhibits Palmitoylation of Tubulin in Human Leukemic Lymphocytes

“…The role that microtubules play in the vinblastineinduced apoptotic process is not clear [15][16][17] . One basic question is: does a low, clinically relevant concentration of vinblastine alter microtubule physiology during the apoptotic process.…”