Fig. 1

CLDN6 regulates breast cancer metastasis via autophagy in vitro and vivo. A Western blot showed levels of autophagy-related proteins in MCF-7 and MDA-MB-231 cells with or without CLDN6 overexpression. B LC3 puncta was visualized by IF analysis, and the percentage of LC3 positive cells was quantified, zoomed-in image (right). Scale bar: 50 μm. C Western blot showed levels of autophagy after treated with 2 mM 3-MA or 25 μM CQ for 24 h. (D-E) Wound healing assay and transwell migration and invasion assays were performed in CLDN6-overexpression cells treated with 3-MA or CQ. Scale bar: 200 μm (D) and 50 μm (E). Results of (A − E) were from three independent experiments. F Bioluminescence imaging (BLI) was used to monitor metastases of BALB/c-nu mice. Representative lung metastatic nodes (red arrowheads). Representative H&E staining of lung sections from the three groups (n = 5 mice/group), Scale bar: 2 mm (left), 200 μm (right). G The number of surface metastatic nodes per lung in each group. H The areas were quantified with Image-Pro Plus and the tumor ratio (%) was determined as (tumor area)/(total lung area) × 100%. I The number of mice with lung metastasis was counted in each group. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001 and ns: no significance