Journal: Advanced Science
Article Title: NAT10 Promotes Gastric Cancer Liver Metastasis by Modulation of M2 Macrophage Polarization and Metastatic Tumor Cell Hepatic Adhesion
doi: 10.1002/advs.202410263
Figure Lengend Snippet: NAT10 recruits and polarizes M2‐like macrophages via ac4C modification of CXCL2 mRNA. A) scRNA‐seq data showing the proportions of each cell type in the normal, primary tumor, and metastatic tumor groups. B) MIF staining showing the differences in the expression of NAT10, the number of macrophages (marked by CD68), and the number of M2‐like macrophages (marked by CD206) between the primary tumors and liver metastases of GC patients. C) MIF staining showing the differences in the expression of NAT10, the number of macrophages (marked by F4/80), and the number of M2‐like macrophages (marked by CD206) between the liver metastases of nude mice injected intrasplenically with BGC823 cells overexpressing NAT10 or the corresponding control cells. D) M2‐like macrophages derived from THP‐1 cells that migrated through uncoated filter membranes after 16 h of culture in medium derived from BGC823 cells with NAT10 overexpression or the corresponding control cells. The cells were stained with crystal violet, visualized via microscopy (left panel, scale bars = 200 µm), and counted (right panel). E) qPCR was conducted to measure the mRNA levels of M2‐like markers (CD163 and CD206) in THP‐1 cells cultured with medium derived from BGC823 cells with NAT10 overexpression or the corresponding control cells. F,G) CXCL2, CXCL3, and CXCL8 were identified as overlapping genes between the scRNA‐seq and RNA‐seq (BGC‐P vs BGC‐M3 cells) data. (F) Box plots showing differences in the expression of well‐known macrophage recruitment‐related chemokines among normal, primary tumor, and metastatic tumor cells, as determined via scRNA‐seq. (G) Heatmap showing differences in well‐known macrophage recruitment‐related chemokines between BGC‐P and BGC‐M3 cells according to RNA‐seq. H) The mRNA levels of CXCL2, CXCL3, and CXCL8 in NAT10‐OE GC cells were measured by qRT‐PCR. I) Schematic overview of the experimental design for acRIP‐seq based on cells with stable overexpression and knockout of NAT10 compared with their corresponding controls. J) The ac4C abundance on CXCL2 mRNA transcripts in BGC823 cells and AGS cells, as determined by acRIP‐seq. K) acRIP–qPCR analysis was employed to demonstrate NAT10‐mediated CXCL2 ac4C modification. ac4C modification of CXCL2 increased upon overexpression of NAT10. L) The levels of CXCL2 expression in NAT10‐OE and the corresponding control GC cells treated with actinomycin D (2 µg mL −1 ) at the indicated time points were measured by qRT‐PCR. M) The protein level of CXCL2 in NAT10‐OE GC cells was measured by western blotting. N) The concentration of CXCL2 in the culture supernatant of NAT10‐OE GC cells was measured by ELISA. O) The protein level of CXCL2 in primary tumor and liver metastatic tumor tissues from GC patients was evaluated by IHC staining (scale bars = 100 µm). P) The distribution of the CXCL2 staining score in primary tumors and the corresponding liver metastatic tumors ( n = 12) was determined. Q) Representative images (left panel) and quantification (right panel) of migrated M2‐like macrophages derived from THP‐1 cells cultured in medium derived from NAT10‐KO AGS cells supplemented with human rCXCL2. The cells were stained with crystal violet and visualized via microscopy (scale bar = 200 µm). GC, gastric cancer; scRNA‐seq, single‐cell RNA sequencing; RNA‐seq, RNA sequencing; IHC, immunohistochemical; MIF, multiplex immunofluorescence; OE, overexpressing; KO, knockout. Data are represented as mean ± SEM of three independent experiments. NS, not significant.
Article Snippet: GC cells were plated in 24‐well plates (Corning) at densities that allowed growth to 100% confluence within 24 h. The medium was then collected and added to the lower compartments of a 24‐well Transwell plate (Corning) with or without recombinant CXCL2 (3.6 nm; Novoprotein, Suzhou, China).
Techniques: Modification, Staining, Expressing, Injection, Control, Derivative Assay, Over Expression, Microscopy, Cell Culture, RNA Sequencing, Quantitative RT-PCR, Knock-Out, Western Blot, Concentration Assay, Enzyme-linked Immunosorbent Assay, Immunohistochemistry, Immunohistochemical staining, Multiplex Assay, Immunofluorescence