human fibronectin protein, cf  (Bio-Techne corporation)

Journal: Oncology Research

Article Title: The FN1-ITGB4 Axis Drives Acquired Chemoresistance in Bladder Cancer by Activating FAK Signaling

doi: 10.32604/or.2025.072084

Figure Lengend Snippet: Establishment and characterization of GC (Gemcitabine and Cisplatin)-resistant bladder cancer cell lines and identification of resistance-related proteins. ( A ) GC-resistant T24-R and UC3-R cell lines were generated by gradually increasing GC concentrations. Created in BioRender ( https://BioRender.com ). ( B ) Dose-response curves and calculated half-maximal inhibitory concentration (IC50) values for cisplatin (upper panel) and gemcitabine (lower panel) in parental (T24, UC3) and GC-resistant (T24-R, UC3-R) cell lines. Data are presented as the mean ± SD from at least three independent experiments. ( C ) Apoptosis rates of parental and resistant cell lines after treatment with cisplatin, as determined by flow cytometry. Data are presented as the mean ± SD ( n ≥ 3). ( D ) Transcriptomic and proteomic analyses identified FN1 (Fibronectin), EEF1A2 (Eukaryotic Translation Elongation Factor 1 Alpha 2), MRC2 (Mannose Receptor C-Type 2), RAB6B (RAB6B, Member RAS Oncogene Family), THBS1 (Thrombospondin 1), DYSF (Dysferlin), TMOD1 (Tropomodulin 1), NES (Nestin), and APOE (Apolipoprotein E) as overexpressed in GC-resistant cells. ( E ) RT-qPCR (Reverse Transcription Quantitative Polymerase Chain Reaction) and Western blot confirmed FN1 overexpression in T24-R and UC3-R. ( F ) FN1 staining was stronger in GC-resistant bladder cancer tissues (Chemotherapy Sensitive Group: n = 6; Chemotherapy Resistant Group: n = 6). For all panels, a t -test was used for comparisons between two groups, and one-way ANOVA was used for comparisons among multiple groups. Statistical significance was set at p < 0.05. ns, not significant, * p < 0.05, ** p < 0.01

Article Snippet: For exogenous FN1 stimulation, recombinant human FN1 protein (rFN1) (R&D Systems, 1030-FN, Minneapolis, MN, USA) was used.

Techniques: Generated, Concentration Assay, Flow Cytometry, Quantitative RT-PCR, Reverse Transcription, Real-time Polymerase Chain Reaction, Western Blot, Over Expression, Staining

Journal: Oncology Research

Article Title: The FN1-ITGB4 Axis Drives Acquired Chemoresistance in Bladder Cancer by Activating FAK Signaling

doi: 10.32604/or.2025.072084

Figure Lengend Snippet: ITGB4 is critical for FN1-mediated chemotherapy resistance in bladder cancer cells. ( A ) Differential expression analysis revealed that ITGB4 (highlighted by the red box) was significantly overexpressed in T24-R cells compared to T24, suggesting a role in FN1-mediated resistance. ( B ) Structural modeling shows multiple binding sites between FN1 (blue ribbon) and ITGB4 (green ribbon). ( C ) The interaction between FN1 and ITGB4 had a binding score of −318.75 with a confidence score of 96%, indicating a stable interaction. ( D ) The Co-IP experiment confirmed that there is a mutual binding interaction between FN1 and ITGB4. ( E ) Adding rFN1 to resistant strains increased FAK (Y397) phosphorylation and inhibited apoptosis, whereas ITGB4 silencing reversed these effects, highlighting the dependency of FN1-mediated resistance on ITGB4 expression and activation. For panels ( A , C , E ), a t -test was used for comparisons between two groups, and one-way ANOVA was used for comparisons among multiple groups

Article Snippet: For exogenous FN1 stimulation, recombinant human FN1 protein (rFN1) (R&D Systems, 1030-FN, Minneapolis, MN, USA) was used.

Techniques: Quantitative Proteomics, Binding Assay, Co-Immunoprecipitation Assay, Phospho-proteomics, Expressing, Activation Assay

Journal: Oncology Research

Article Title: The FN1-ITGB4 Axis Drives Acquired Chemoresistance in Bladder Cancer by Activating FAK Signaling

doi: 10.32604/or.2025.072084

Figure Lengend Snippet: FN1 silencing enhances cisplatin-induced apoptosis in bladder cancer cells. ( A ) FN1 knockdown efficiency in T24-R and UC3-R cells was confirmed by Western blot analysis. ( B ) FN1 knockdown efficiency in T24-R and UC3-R cells was confirmed by RT-qPCR analysis. ( C ) Silencing FN1 significantly increased apoptosis in the resistant cell lines by TUNEL staining. ( D ) Silencing FN1 reduced the IC50 of cisplatin in the resistant cell lines by CCK-8 assay. ( E ) In resistant cells, FN1 knockdown induced the expression of pro-apoptotic mediators, including BAX and cleaved-caspase-3, but suppressed levels of the anti-apoptotic protein Bcl-2. ( F ) Cell apoptosis rates were quantified by flow cytometry. For all panels, a t-test was used for comparisons between two groups, and one-way ANOVA was used for comparisons among multiple groups. Statistical significance was set at p < 0.05. ns, not significant, * p < 0.05, ** p < 0.01

Article Snippet: For exogenous FN1 stimulation, recombinant human FN1 protein (rFN1) (R&D Systems, 1030-FN, Minneapolis, MN, USA) was used.

Techniques: Knockdown, Western Blot, Quantitative RT-PCR, TUNEL Assay, Staining, CCK-8 Assay, Expressing, Flow Cytometry

Journal: Oncology Research

Article Title: The FN1-ITGB4 Axis Drives Acquired Chemoresistance in Bladder Cancer by Activating FAK Signaling

doi: 10.32604/or.2025.072084

Figure Lengend Snippet: FN1 silencing inhibits tumor growth in vivo , enhancing cisplatin sensitivity. ( A ) Representative images of tumors from each treatment group. ( B ) Tumor volume growth curves over time measured in the T24-R xenograft model. ( C ) Apoptosis in tumor tissues was detected by TUNEL staining. ( D ) Immunohistochemical analysis showed decreased FN1 expression in tumor sections from the FN1 knockdown group. For all panels, a t -test was used for comparisons between two groups, and one-way ANOVA was used for comparisons among multiple groups. Statistical significance was set at p < 0.05. * p < 0.05, *** p < 0.001

Article Snippet: For exogenous FN1 stimulation, recombinant human FN1 protein (rFN1) (R&D Systems, 1030-FN, Minneapolis, MN, USA) was used.

Techniques: In Vivo, TUNEL Assay, Staining, Immunohistochemical staining, Expressing, Knockdown

Journal: Oncology Research

Article Title: The FN1-ITGB4 Axis Drives Acquired Chemoresistance in Bladder Cancer by Activating FAK Signaling

doi: 10.32604/or.2025.072084

Figure Lengend Snippet: FN1 regulates FAK (Y397) phosphorylation and mediates cisplatin resistance in bladder cancer cells. ( A ) Silencing FN1 in resistant cell lines reduced the phosphorylation of FAK (Y397) as detected by Western blot. ( B ) T24 and UC3 parental and resistant cells were treated with a fixed dose of cisplatin along with a gradient of rFN1 for 48 h. Phosphorylation of FAK (Y397) was assessed by Western blot. Resistant cells (T24-R, UC3-R) showed sensitivity to rFN1 at lower concentrations under cisplatin stress. ( C ) Silencing FN1 in resistant cell lines reduced the phosphorylation of FAK (Y397) as detected by immunofluorescence. ( D ) rFN1 addition increased resistance index in resistant strains. ( E ) The addition of rFN1 reduced apoptosis in resistant strains. For all panels, a t -test was used for comparisons between two groups, and one-way ANOVA was used for comparisons among multiple groups. Statistical significance was set at p < 0.05. ns, not significant, * p < 0.05, *** p < 0.001

Article Snippet: For exogenous FN1 stimulation, recombinant human FN1 protein (rFN1) (R&D Systems, 1030-FN, Minneapolis, MN, USA) was used.

Techniques: Phospho-proteomics, Western Blot, Immunofluorescence