Fig. 4

Disruption of PLOD2 or knockdown of PAI-1 abrogates linearized collagen and tumor metastasis in vivo. a Schematic diagram of the development of the breast cancer metastasis model. b Kaplan-Meier survival analysis for the mice. c,d Representative images and quantification bioluminescence of breast tumor bearing mice treated with minoxidil (2.5 mg/kg). Metastatic burden was detected by bioluminescent imaging (BLI) 56 days after injection. e The metastatic nodes in the lungs were detected by hematoxylin and eosin (H&E) staining. Arrows indicate metastatic colonization. Scale bars, 100 μm. f Human DNA content in mouse lungs determined by qPCR (n = 6). g The collagen deposition and PAI-1, PLOD2 expression in tumors were detected by Masson trichrome staining and immunohistochemistry staining, respectively. h The degree of fibrillar organization was evaluated by a pathologist. The linearity score (from 0 to10) indicates the degree of fibrillar organization. Higher score suggested greater fibrillar organization. i Immunoblot analysis of PLOD2 expression in tumor tissues from MDA-MB-231 injected alone, or co-injection MDA-MB-231 cells with adipose, with or without minoxidil treatment, or silencing of PAI-1 in the MDA-MB-231 cells co-injection with adipose tissues. j The relative PLOD2 expression at protein levels were analyzed by using GAPDH as the loading control (n = 4 in different groups). The P-values < 0.05 were considered statistically significant for all tests.