Establishment and characterization of urine-resistance cell sub-strain of human bladder cancer

Background: Metastasis of tumor implantation includes a series of processes from detachment from the primary tumor to formation of the implanted metastase. Tumor cells survival in urine is a necessary condition for metastasis. Adaptation to urine is essential for this.

Objective: Establish a urine-resistant cell sub-strain of human bladder cancer cell line (ET cell lines), and study different characteristics compared to parent cells.

Methods: EJ cell lines were cultured in nutrient medium. Urine-resistance cell sub-strain (EJ-U) was harvested after prolonged culture by gradually increasing the concentration of urine. Gen chip was used to detect the genome series of EJ and EJ-U and to analyze the difference of gene expression.

Results: EJ-U in urine had a higher survival rate after 24 hours in urine compared with EJ. The EJ-U had almost the same growth velocity with EJ, and they had the analogous growth curves. The time-duration for EJ-U to survive was longer than EJ in urine. In gene ontology analysis, 272 significant different genes were found.

Conclusion: EJ-U cell sub-strain was more adaptable than its parent cell lines EJ. The different genes may explain the reason why bladder cancer cells could survive for a long time in urine.