Fig. 2: BCa cells can better promote the transformation of NFs into CAFs than non-malignant bladder cells, and appropriate concentrations of cisplatin can accelerate this process.

a Cartoon showing the transwell co-culture system: CM from BCa cells or SVHUCs was plated into the lower chambers of the transwells, and 1 × 10⁵ NFs cells were plated onto the upper chambers. When implementing fibroblast recruitment assays, a polycarbonate membrane with a 5-μm pore size was inserted between the two chambers. For the noncontact co-culture system, a polycarbonate membrane with a 0.4-μm pore size was used. b After 8 h of incubation, the fibroblasts that migrated into the lower chambers were collected and counted. c The α-SMA immunofluorescence staining assay was implemented on all fibroblasts in the noncontact co-culture system after 8 h of incubation, and the percentage of α-SMA(+) fibroblasts was counted. d Western blot and quantitative real-time PCR (qRT-PCR) results showed the expression of the CAF-specific markers ACTA2 (α-SMA) and FAP in fibroblasts in the noncontact co-culture system after 8 h of incubation. e Different concentrations of cisplatin were added to the noncontact co-culture system. After 8 h of incubation, the protein and mRNA levels of ACTA2 and FAP in fibroblasts were analysed. f, g Different concentrations of cisplatin were added to the noncontact co-culture system. After 8 h of incubation, the percentage of α-SMA(+) fibroblasts was counted in the upper chambers using immunofluorescence. The first column of Fig. 2g (no cisplatin added) is also the experimental condition of Fig. 2c. In the qRT-PCR analysis, we used the β-actin gene as the normalization control. Data are presented as the mean ± SD. *P < 0.05