Extended Data Fig. 3: The cleaved to intact Col I ratio controls macropinocytosis and mitochondrial biogenesis.
From: Collagenolysis-dependent DDR1 signalling dictates pancreatic cancer outcome
a, Macropinocytosis (MP) visualization and quantification using TMR-DEX in KPC cells co-cultured with WT or R/R fibroblasts and incubated in LG medium for 24 h. KPC cells were marked by cytokeratin 18 (CK18, green). b, Representative images, and MP quantification in TMR-DEX-injected pancreatic tissue from Col IWT or Col Ir/r mice 4 wk after orthotopic KPC cell transplantation. Carcinoma cells are marked by EpCAM staining (green). Quantification is on the right. c, qRT-PCR analysis of MP-related mRNAs in liver tumours 2 wk after i.s. KPC cell transplantation into CCl4 pretreated ColWT or Colr/r mice. Exact P values are shown in Source Data. d, IB analysis of MP-related proteins in above liver tumours. e, Representative images, and quantification of Mito. (ATP5B, green) in pancreatic tissue from indicated mice analysed as in (b). Carcinoma cells are marked by EpCAM staining (red). Quantification is on the right. f,g, Representative images, and quantification of Mito. (TIM23) and MP in TMR-DEX-incubated KPC cells grown on mixed ECM produced by R/R and WT (R:W) (f) or R/R and Col IΔ R/R (R:KO) (g) fibroblasts in the indicated ratios and incubated in LG medium for 24 h. IB analysis of iCol I or cCol I (3/4 Col I) in above ECM preparations is shown at the bottom. Results in (a,f,g) (n = 6 fields), (b,c,e) (n = 4 mice) are mean ± s.e.m. Statistical significance determined by two-tailed t-test. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001. Scale bars, 10 μm.
