Assays were performed in triplicate. Statistical
analysis All check details experiments were performed in triplicate and data Tanespimycin cell line were expressed as mean values ± SD. The Pearson product-moment correlation coefficient was used to evaluate the correlation (linear dependence) of cell proliferation, viability and sirolimus concentration. Data were analysed using SPSS 12 statistical software (SPSS Inc. USA) and statistical significance was set at p < 0.05. Results Cell proliferation The results of the MTT assay to detect sirolimus-induced anti-proliferative activity in T24 cell line are found in Table 1. T24 cancer cells were treated with various concentrations of sirolimus. As shown in Figure 1, sirolimus had growth inhibition effects on T24 cancer cells in a dose-dependent manner. Statistically, anti-proliferative activity was correlated with sirolimus concentration, the Pearson correlation of these two markers is r = 0.830 to p < 0.01. Figure 1 Linear relationship between the proliferation
inhibitory rate (%) and sirolimus concentration (y = 0.2074x + 23.299; r 2 = 0.6882). Table 1 Effect of sirolimus in T24 cancer cell line. Concentration A570 nm A690 nm Mean ± SD 0.525 0.201 0 ng/mL 0.828 0.108 0.557 ± 0.207 0.828 0.201 0.588 0.096 5 ng/mL 0.639 0.078 0.481 ± 0.086 0.72 0.33 0.528 0.054 10 ng/mL 0.468 0.063 0.374 ± 0.117 0.47 0.225 0.516 0.213 40 ng/mL 0.489 0.087 0.310 ± 0.087 0.477 0.25 0.78 0.489 60 ng/mL 0.687 0.354 0.267 ± 0.080 0.339 0.162 0.474 0.288 100 ng/mL 0.573 0.246 0.301 ± 0.104 0.657 0.267 0.501 0.276 STI571 150 ng/mL 0.42 0.318 0.22 ± 0.115 0.618 0.285 0.504 0.417 200 ng/mL 0.294 0.255 0.193 ± 0.226 0.576 0.123 0.345 0.264 250 ng/mL 0.3 0.27 0.199 ± 0.249 0.618 0.132 Cell viability The results of cell viability after the incubation of OSBPL9 the T24 cell line with sirolimus at different concentrations are displayed in Figure 2. It can be seen from the figure that there was a concentration-dependent decrease in cell viability
for all concentrations tested. A significant correlation was found between cell viability and sirolimus concentration (r = -0.896, p < 0.01). Figure 2 Linear relationship between the cell viability rate (%) and sirolimus concentration (y = -0.1993x + 85.162; r 2 = 0.8023). Discussion The findings of the present study revealed that sirolimus inhibits T24 bladder cancer cell proliferation and decrease the cell viability including in clinical dose of this mTOR inhibitor. These data may be relevant if we remember the action of the mTOR pathway. mTOR is a 290 kDa serine-threonine kinase that regulates both cell growth and cell cycle progression through its ability to integrate signals from nutrient and growth factor stimuli [24]. Tumour angiogenesis may depend on mTOR signalling.