ABSTRACT
It has been suggested that progression of bladder transitional cell cancer (BTCC) may be regulated at the molecular level by a typical pattern of expression of genes involved in apoptosis. Re- cently Livin, belonging to the inhibitors of apoptosis (IAP) family, has been found to be expressed in most solid tumors, where its expression is suggested to have clinical significance. In order to explore the significance of Livin expression in the development of BTCC, immunohistochemistry and RT-QPCR were used to detect the expression of Livin mRNA in tumor tissues and adjacent normal tissues of 30 cases of BTCC. The results showed that the positive rate of Livin expression in adjacent normal tissues and tumor tissues was 0 and 60% (18/30) respectively. The -△△CT value of Livin in BTCC tissues was 8.0454 (7.4264-8.6644) times of that in adjacent normal tissues. The expression of Livin mRNA had no correlation with tumor pathological grades and clinical stages. It was sug- gested that there was weak expression ? Livin mRNA in adjacent normal tissues, but strong in tumor tissues.
ABSTRACT
The effects of synthetic Smac peptide (SmacN7) on chemotherapeutic sensitivity of bladder cancer cells were investigated. SmacN7 penetratin peptide was synthesized and delivered into T24 cells. MTT assay was used to evaluate the viability of T24 cells induced by low-dosage of MMC. Flow cytometry was used to analyze the proportions of apoptosis. Western blot was used to detect the expression of XIAP and Caspase-3. The activity of Caspase-3 was measured and the effect of SmacN7 combined with MMC on T24 cell lines was also determined. The results showed that SmacN7 penetratin peptide could successfully interact with endogenous XIAP, increase the proportions of apoptosis of T24 cell lines induced by low-dosage of MMC in a dose-and time-dependent manner. An obvious down-regulation of XIAP expression and up-regulation of Caspase-3 was identified by Western blot. The activity of Caspase-3 in experimental group was significantly increased as compared with that in the control group. As compared with MMC group, the viability of T24 cells in SmacN7 penetratin peptide + MMC group was markedly decreased to 2.22 and 3.61 folds at 24h and 48h respectively. It was concluded that SmacN7 penetratin peptide could act as a cell-permeable IAP inhibitor, inhibit the proliferation, induce apoptosis and enhance the chemo-sensitivity of bladder cancer cells to MMC. These findings indicate that SmacN7 penetratin peptide may be a very promising ageut for bladder cancer treatment when used in combination with chemotherapy.