Fig 2: ADAMTS19 downregulates S100A16 by participating in the process of P65 phosphorylation of the NF-?B pathway. (A) Nucleus phospho-P65 was decreased in MGC803-ADAMTS19 and increased in BGC823-shADAMTS19 cells. (B) Co-immunoprecipitation assays revealed that ADAMTS19 interacted with P65 in MGC803. (C) Double immunofluorescence assays revealed that ADAMTS19 was co-localized with P65 in cytoplasm in MGC803 and MKN45 cells after transfection with pCDNA3.1-ADAMTS19-3xFlag, and nucleus P65 was significantly downregulated in MGC803 cells. (D) The positive correlation between S100A16 and P65 was verified using GEPIA 2. (E) Dual-luciferase reporter gene assays showed that P65 acted as a transcription factor of S100A16. (F) Brief schematic model showing that ADAMTS19 regulated S100A16 via the NF-?B pathway and participated in P65 phosphorylation. The data are presented as means ± standard deviations. * p < 0.05; ** p < 0.01; *** p < 0.001.

Fig 3: ADAMTS19 suppresses GC cell migration and invasion in vitro. (A) ADAMTS19 protein expression levels measured in seven gastric cancer cell lines (MKN1, MKN45, SGC7901, AGS, BGC823, HGC27, and MGC803) and one normal gastric epithelial cell line (GES1) by Western blotting. (B) MGC803 and MKN45 cells with low expression of endogenous ADAMTS19 were chosen to construct stably-overexpressed ADAMTS19 cells transfected with a lentiviral vector, and BGC823 and SGC7901 cell lines with high endogenous ADAMTS19 were stably transfected with shRNA through a lentiviral vector. ADAMTS19 expression in stably transfected cells was confirmed by Western blotting. (C–F) Overexpression of ADAMTS19 suppressed GC cell migration and invasion, while ADAMTS19 knockdown reversed the effects. (G–J) Wound healing assays showed that overexpression of ADAMTS19 significantly inhibited wound healing in MKN45 and MGC803, whereas ADAMTS19 knockdown promoted wound healing in BGC823 and SGC7901. The data are presented as means ± standard deviations. * p < 0.05; ** p < 0.01; *** p < 0.001.

Fig 4: ADAMTS19 is downregulated in gastric cancer (GC). (A) Oncomine analysis revealed that ADAMTS19 mRNA expression levels are lower in tumor tissue than in normal tissue by meta-analysis. The intensity gene expression indexed with the color code bars, the median rank is used to demonstrated the gene rank in each analysis. (B) Quantitative real-time polymerase chain reaction (qRT-PCR) on 45 paired samples showed that ADAMTS19 mRNA expression levels were lower in tumor tissue than in adjacent normal tissue. (C) Immunohistochemistry (IHC) analysis of 53 paired samples showed that ADAMTS19 expression was lower in tumor tissue than in adjacent normal tissue. (D) Representative IHC images of tumor and adjacent normal tissue. (E) High ADAMTS19 expression predicted better overall survival than low ADAMTS19 expression in GC patients (the best cutoff score of 5.5 was obtained using X-tile). The data are presented as means ± standard deviations. * p < 0.05; *** p < 0.001.

Fig 5: S100A16 is a downstream of ADAMTS19 and acts as a tumor promoter, promoting cell migration and invasion. (A) Heat map analysis showed altered genes in MGC803-ADAMTS19 and MGC803-vector cells. (B) Gene Ontology analysis showed that the altered genes are involved in biological processes, such as cell adhesion, extracellular matrix organization, inflammatory response, and cell surface receptor signaling pathway. (C) Gene set enrichment analysis (GSEA) showed the enrichment of ADAMTS19-associated genes in HALLMARK_TNF_SIGNALING VIA_NFKB and other pathways. The plot was drawn using R and RStudio. (D) Dual-luciferase gene reporter assays revealed that ADAMTS19 could regulate the S100A16 transcription directly in MKN45 and BGC823. (E,F) Quantitative RT-PCR and Western blot analysis showed that S100A16 protein levels were affected by ADAMTS19. (G,H) Ectopic expression of S100A16 reversed the inhibition of cell migration and invasion by ADAMTS19 in MGC803 and BGC823 cells. The data are presented as means ± standard deviations. * p < 0.05; ** p < 0.01; *** p < 0.001.