A Disintegrin and Metalloproteinase with Thrombospondin motifs 19 (ADAMTS19) has been reported to participate in the pathogenesis of solid cancers. However, its role in gastric cancer (GC) remains undocumented. Using immunohistochemistry (IHC) staining and quantitative real-time polymerase chain reaction (qRT-PCR) on GC tissues and adjacent normal tissues, we found that ADAMTS19 was downregulated in GC tissues (IHC: p < 0.001; qRT-PCR: p = 0.017). Further investigation revealed that ADAMTS19 correlated with distant metastasis (p = 0.008) and perineural invasion (p = 0.018) and that patients with low ADAMTS19 had worse overall survival (p = 0.021). Gain- and loss-of-function assays showed that ADAMTS19 suppressed cell migration and invasion in vitro. Using bioinformatics analysis and co-immunoprecipitation, immunofluorescence, and dual-luciferase reporter gene assays, we confirmed that ADAMTS19 binds with cytoplasm P65, decreasing the nucleus phosphorylation of P65, a crucial transcription factor in the nuclear factor kappa-B (NF-κB) pathway, thereby downregulating S100 calcium-binding protein A16 (S100A16) expression. S100A16 acted as the downstream of ADAMTS19, reversing the suppression of cell migration and invasion by ADAMTS19 in vitro. A combination of ADAMTS19 and S100A16 expression provided the optimal prognostic indicator for GC. Patients with ADAMTS19^high-S100A16^low had better overall survival than ADAMTS19^low-S100A16^high patients (p = 0.006). These results suggest that ADAMTS19 suppresses cell migration and invasion by targeting S100A16 via the NF-κB pathway and that ADAMTS19 and S100A16 are potential metastasis and survival biomarkers for GC.

A disintegrin and metalloproteinase with thrombospondin motifs 16 (ADAMTS16) has been reported to be involved in the pathogenesis of solid cancers. However, its role in gastric cancer (GC) is unclear. In this study, the role of ADAMTS16 in gastric cancer was investigated. The effects of ADAMTS16 on cell migration, invasion, and proliferation were investigated by functional experiments in vivo and in vitro. Downstream signal pathways of ADAMTS16 were confirmed by using bioinformatics analysis, co-immunoprecipitation, and immunofluorescence. Meanwhile, bioinformatics analysis, qRT-PCR, western blot, and dual-luciferase reporter gene analysis assays were used to identify ADAMTS16 targets. The expression of ADAMTS16 in GC was analyzed in public datasets. The expression of ADAMTS16 and its correlations with the clinical characteristics of GC were investigated by immunohistochemistry. Ectopic ADAMTS16 expression significantly promoted tumor cell migration, invasion, and growth. Bioinformatics analysis and western blot showed that ADAMTS16 upregulated the IFI27 protein through the NF-κb pathway, which was confirmed by immunofluorescence and western blot. Dual-luciferase reporter gene analysis identified a binding site between P65 and IFI27 that may be directly involved in the transcriptional regulation of IFI27. IFI27 knockdown reversed the promoting effect of ADAMTS16 on cell invasion, migration, and proliferation indicating that ADAMTS16 acts on GC cells by targeting the NF-κb/IFI27 axis. ADAMTS16 was associated with poor prognosis in clinical characteristics. ADAMTS16 promotes cell migration, invasion, and proliferation by targeting IFI27 through the NF-κB pathway and is a potential progressive and survival biomarker of GC.

Background: Gastric cancer (GC) is a fatal cancer with unclear pathogenesis. In this study, we explored the function and potential mechanisms of intercellular adhesion molecule 2 (ICAM2) in the development and advancement of GC. Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were performed to quantify ICAM2 expression in harvested GC tissues and cultured cell lines. Immunohistochemical analyses were conducted on a GC tissue microarray to quantify ICAM2 expression and explore its implication on the prognosis of GC patients. In vitro experiments were carried out to reveal the biological functions of ICAM2 in GC cell lines. Further, in vivo experiments were conducted using xenograft models to assess the impact of ICAM2 on GC development and metastasis. Western blot, immunofluorescence, immunoprecipitation, luciferase assay, chromatin immunoprecipitation, and ubiquitination analysis were employed to investigate the underlying mechanisms. Results: ICAM2 expression was downregulated in GC, positively correlating with advanced T stage, distant metastasis, advanced clinical stage, vessel invasion, and shorter patient survival time. ICAM2 overexpression suppressed the proliferation, migration, invasion, metastasis of GC cells as well as their ability to form tumors, whereas ICAM2 knockdown yielded opposite results. Erythroblast transformation-specific-related gene (ERG) as a transcription factor promoted the transcription of ICAM2 by binding to the crucial response element localized within its promoter region. Further analysis revealed that ICAM2 reduced radixin (RDX) protein stability and expression. In these cells, ICAM2 bound to the RDX protein to promote the ubiquitination and degradation of RDX via NEDD4 Like E3 Ubiquitin Protein Ligase (NEDD4L), and this post-translational modification resulted in the inhibition of GC. Conclusions: In summary, this study demonstrates that ICAM2, which is induced by ERG, suppresses GC progression by enhancing the ubiquitination and degradation of RDX in a NEDD4L-dependent manner. Therefore, these results suggest that ICAM2 is a potential prognostic marker and a therapeutic target for GC.

Background: Ladinin-1 (LAD1), an anchoring filament protein, has been associated with several cancer types, including cancers of the colon, lungs, and breast. However, it is still unclear how and why LAD1 causes gastric cancer (GC). Methods: Multiple in vitro and in vivo, functional gains and loss experiments were carried out in the current study to confirm the function of LAD1. Mass spectrometry was used to find the proteins that interact with LAD1. Immunoprecipitation analyses revealed the mechanism of LAD1 involved in promoting aggressiveness. Results: The results revealed that the LAD1 was overexpressed in GC tissues, and participants with increased LAD1 expression exhibited poorer disease-free survival (DFS) and overall survival (OS). Functionally, LAD1 promotes cellular invasion, migration, proliferation, and chemoresistance in vivo and in vitro in the subcutaneous patient-and cell-derived xenograft (PDX and CDX) tumor models. Mechanistically, LAD1 competitively bound to Vimentin, preventing it from interacting with the E3 ubiquitin ligase macrophage erythroblast attacher (MAEA), which led to a reduction in K48-linked ubiquitination of Vimentin and an increase in Vimentin protein levels in GC cells. Conclusions: In conclusion, the current investigation indicated that LAD1 has been predicted as a possible prognostic biomarker and therapeutic target for GC due to its ability to suppress Vimentin–MAEA interaction.