Fig. 5: Depletion of TGFα rescues the promoting effect of rCAFs on chemoresistance in both tumor cells and patient derived organoids.

a Western blot and RT-PCR analysis of the TGFα expression in rCAFs after transfected with non-silencing control (NSC) siRNA or TGFα targeting siRNA-1/-2. b DDP IC₅₀ experiments of FaDu or Tu686 cells after exposed with either CM from siTGFα or siNSC transfected rCAFs. c DDP IC₅₀ experiments of FaDu or Tu686 cells after treated with CM from rCAFs in the presence of IgG control or cetuximab (n = 3 independent experiments). d Transwell invasion assays of DDP treated cancer cells in the presence of CM from siTGFα or siNSC transfected rCAFs. e Invasion assays for DDP treated FaDu cells exposed with CM from rCAFs in the presence or absence of IgG antibody or cetuximab. Bar charts show the relative invaded cell number in each group (n = 3 independent experiments). f Representative bright field images of HNSCC patient derived organoids after co-culture with/without rCAFs or sCAFs in the presence or absence of DDP -/+ IgG control or cetuximab. Line graphs show the growth of tumor organoids in each treatment group (n = 3 independent experiments). Ctrl represents tumor organoids without co-culture with sCAF or rCAF. g Western blot analysis of p-EGFR, total EGFR, p-Src, total Src, p-STAT3, and total STAT3 expression in FaDu cells after treated with CM from sCAFs or rCAFs in the presence or absence of 3 μM DDP. h Western blot analysis of the indicated protein expression in FaDu cells after treated with 3 μM DDP in the presence of CM from sCAFs or rCAFs together with or without 100 μg/mL cetuximab. Data are shown as means ± S.E.M. *P < 0.05, **P < 0.01, ***P < 0.001, N.S. not significant. a, d, e One-way ANOVA. f Two-way ANOVA. Scale bars in (d, e) represent 100 μm, (f) 200 μm.