Rapid noninvasive detection of bladder cancer using survivin antibody-conjugated gold nanoparticles (GNPs) based on localized surface plasmon resonance (LSPR).

BACKGROUND: Bladder cancer is diagnosed by the use of several biomarkers, including survivin. This protein has an important role in the cancer progression by controlling the rate of cell apoptosis. Findings show that there is no survivin in normal tissues, whereas the level of survivin expression increases in tumor cells.

DESIGN: The purpose of this study was to specify the reactive antibodies to survivin protein as a biomarker to determine the bladder cancer stage with ELISA method and using GNPs conjugated with survivin antibody. The serum and urine samples of patients with bladder cancer were collected among those referred to Sina Hospital, Tehran, Iran. The survivin protein level was measured in the serum and urine by ELISA technique and in the urine by GNPs conjugated with survivin.

RESULTS: Based on the results of ELISA, the serum and urinary levels of survivin increased significantly in T3 and T4 stages of the disease (high grades), compared with the healthy individuals. Also, using conjugated GNPs, survivin protein was detected in the urine specimens of patients at all grades (low and high grades).

CONCLUSION: Our findings showed that using the ELISA technique, the increased level of survivin could be identified in high grades of bladder cancer, but using anti-survivin antibody-conjugated GNPs, bladder cancer can be detected in early stages. The applied method was found to be a rapid tool, dependent on visible color changes and colorimetric detection, without any need for reader devices.