中国生物工程杂志

Objective: Bladder cancer cell lines and organoid models with FGFR3 mutations were constructed at different sites first, and then their sensitivity to different tyrosine kinase inhibitors targeting FGFR3 gene mutations was determined. Methods: Cell line models with wild type FGFR3, point mutant FGFR3 (S249C, R248C and Y373C) and FGFR3-TACC3 fusion were established. Eight tyrosine kinase inhibitors were then used to test for differences in drug sensitivity in different stable cells. The phosphorylation level of FGFR3 downstream pathway protein was detected by Western blot analysis to analyze the mechanism of the difference in tyrosine kinase inhibitor (TKI) sensitivity in different stable cells. Organoid models were constructed using bladder cancer patient tissues, and the above experiment was repeated. The sensitivity of different mutant bladder cancer organoids to different TKIs was determined at the organoid level. Results: FGFR3 point mutation R248C and FGFR3-TACC3 fusion increased by 5-10 fold compared with wild type FGFR3 to half of tyrosine kinase inhibitors at the cell line level (P<0.05). Organoids derived from tumor tissue of bladder cancer patients were successfully constructed. This confirmed that the organoid has the organizational and genetic characteristics of the tumor in situ. The FGFR3 point mutations S249C and Y373C did not show significant differences in sensitivity, which can be 1-5 fold different from the wild type. The FGFR3-TACC3 fusion and the FGFR3 point mutation Y373C can significantly alter the sensitivity of cells to drugs at the organoid level. Conclusions: This study successfully constructed cell lines and organoids with different FGFR3 mutations, further demonstrating that different FGFR3 mutations have different sensitivities to tyrosine kinase inhibitors, and that organoids with the FGFR3 point mutation R248C have high sensitivity to all TKI drugs.