EWI2 prevents EGFR from clustering and endocytosis to reduce tumor cell movement and proliferation

Actinidia chinensis polysaccharide interferes with the epithelial-mesenchymal transition of gastric cancer by regulating the nuclear transcription factor-κB pathway to inhibit invasion and metastasis

OBJECTIVE

To investigate the mechanisms of the effect of Actinidia chinensis polysaccharide (ACPS) on the invasion and metastasis of gastric cancer cells.

METHODS

BGC-823-Luc gastric cancer cells stably transfected with a luciferase gene were used to establish an insitutransplanted tumor mouse model. A live mouse imaging system was used to observe tumor growth, and hematoxylin and eosin staining was applied to analyze tissue histopathology. Transwell and scratch wound assays were performed to examine the invasive and migratory ability of BGC-823 cells. Immunofluorescence, confocal microscopy, immunohistochemistry, and Western blot assays were used to analyze the expressions of the nuclear transcription factor-κB (NF-κB) signaling pathway and epithelial-mesenchymal transition (EMT)-related proteins.

RESULTS

ACPS significantly inhibited the growth of subcutaneously transplanted BGC-823-Luc gastric cancer tumors in nude mice and reduced inflammatory cell infiltration in tumor tissues. ACPS inhibited Epidermal Growth Factor-induced invasion, migration, and morphological changes in the cytoskeleton of BGC-823 cells. ACPS inhibited gastric cancer EMT and decreased the expression of matrix metallopeptidase 9, N-cadherin and p-NF-κB p65 in transplanted tumor tissues. ACPS inhibited the expression of matrix metalloproteinases and vascular adhesion factors in BGC-823 cells, promoted p65-NF-κB nuclear translocation, and regulated proteins associated with the NF-κB p65 pathway.

CONCLUSIONS

ACPS inhibited gastric cancer invasion and metastasis both in vivo and in vitro, which evidenced the inhibition of gastric cancer EMT viaregulating the NF-κB inflammatory pathway.

IGSF8 is a potential target for the treatment of gliomas

BACKGROUND

Immunoglobulin superfamily member 8, or IGSF8, is a member of the recently identified immunoglobulin family of proteins. It is mostly produced on cell membranes and has a unique transmembrane structure. It has recently been demonstrated that there is a strong correlation between the expression variation of IGSF8 and the growth of gliomas. Therefore, we used data from the TCGA and CGGA databases to evaluate the function of IGSF8.

METHODS

The TCGA and GTEx data sets' RNA-seq data were utilized to examine IGSF8 expression. The Gene Cards database was utilized to get IGSF8 protein data. The Cluster Profiler data package was used to carry out the IGSF8 enrichment study. The GO and KEGG databases were used to examine the relationship between IGSF8 and cellular physiological and biochemical processes. The TCGA immune cell infiltration scores were obtained from online databases and published studies. Clinical survival data from TCGA and CGGA were used to investigate the predictive significance of IGSF8.

RESULTS

TGGA revealed that the majority of cancers had differential expression of IGSF8. IGSF8 was discovered to be enriched in numerous significant pathways in tumor cells by GO and KEGG. Moreover, a strong correlation was seen between the expression of IGSF8 and the immunomodulatory interactions that occur between non-lymphocytes and lymphocytes. T-cell infiltration, immunological checkpoints, immune-activating and immune-suppressive genes, chemokines, and chemokine receptors were all strongly correlated with IGSF8 expression. Lastly, the TCGA and CGGA databases showed a strong correlation between IGSF8 and the grade and prognosis of gliomas.

CONCLUSION

According to our findings, IGSF8 may be a glioma marker. In order to control the immunological microenvironment, IGSF8 may cooperate with a number of immune checkpoints. This information may be utilized to create novel targeted immunotherapy medications.

EWI2 and its relatives in Tetraspanin-enriched membrane domains regulate malignancy

Experimental studies on immunoglobulin superfamily (IgSF) member EWI2 reveal that it suppresses a variety of solid malignant tumors including brain, lung, skin, and prostate cancers in animal models and inhibits tumor cell movement and growth in vitro. While EWI2 appears to support myeloid leukemia in mouse models and maintain leukemia stem cells. Bioinformatics analyses suggest that EWI2 gene expression is downregulated in glioblastoma but upregulated in melanoma, pancreatic cancer, and liver cancer. The mechanism of action for EWI2 is linked to its inhibition of growth factor receptors and cell adhesion proteins through its associated tetraspanin-enriched membrane domains (TEMDs), by altering the cell surface clustering and endolysosome trafficking/turnover of these transmembrane proteins. Recent studies also show that EWI2 modulates the nuclear translocation of ERK and TFEB to change the activities of these gene expression regulators. For EWI2 relatives including FPRP, IgSF3, and CD101, although their roles in malignant diseases are not fully clear and remain to be determined experimentally, FPRP and IgSF3 likely promote the progression of solid malignant tumors while CD101 seems to modulate immune cells of tumor microenvironment. Distinctive from other tumor regulators, the impacts of EWI subfamily members on solid malignant tumors are likely to be context dependent. In other words, the effect of a given EWI subfamily member on a tumor probably depends on the molecular network and composition of TEMDs in that tumor. Collectively, EWI2 and its relatives are emerged as important regulators of malignant diseases with promising potentials to become anti-cancer therapeutics and cancer therapy targets.