The significance of post-translational removal of α-DG-N in early stage endometrial cancer development

Polymerizing laminins in development, health, and disease

Polymerizing laminins are multi-domain basement membrane (BM) glycoproteins that self-assemble into cell-anchored planar lattices to establish the initial BM scaffold. Nidogens, collagen-IV and proteoglycans then bind to the scaffold at different domain loci to create a mature BM. The LN domains of adjacent laminins bind to each other to form a polymer node, while the LG domains attach to cytoskeletal-anchoring integrins and dystroglycan, as well as to sulfatides and heparan sulfates. The polymer node, the repeating unit of the polymer scaffold, is organized into a near-symmetrical triskelion. The structure, recently solved by cryo-electron microscopy in combination with AlphaFold2 modeling and biochemical studies, reveals how the LN surface residues interact with each other and how mutations cause failures of self-assembly in an emerging group of diseases, the LN-lamininopathies, that include LAMA2-related dystrophy and Pierson syndrome.

Protective role for the N-terminal domain of α-dystroglycan in Influenza A virus proliferation

α-Dystroglycan (α-DG) is a highly glycosylated basement membrane receptor that is cleaved by the proprotein convertase furin, which releases its N-terminal domain (α-DGN). Before cleavage, α-DGN interacts with the glycosyltransferase LARGE1 and initiates functional O-glycosylation of the mucin-like domain of α-DG. Notably, α-DGN has been detected in a wide variety of human bodily fluids, but the physiological significance of secreted α-DGN remains unknown. Here, we show that mice lacking α-DGN exhibit significantly higher viral titers in the lungs after Influenza A virus (IAV) infection (strain A/Puerto Rico/8/1934 H1N1), suggesting an inability to control virus load. Consistent with this, overexpression of α-DGN before infection or intranasal treatment with recombinant α-DGN prior and during infection, significantly reduced IAV titers in the lungs of wild-type mice. Hemagglutination inhibition assays using recombinant α-DGN showed in vitro neutralization of IAV. Collectively, our results support a protective role for α-DGN in IAV proliferation.

Expression and potential role of SNF5 in endometrial carcinoma

Background

SNF5 is a key protein in regulating cell proliferation and apoptosis in various cancers. However, the physiological roles of SNF5 in Endometrial carcinoma (EC), which is one of the most frequent malignancies of the female reproduction worldwide, remains unclear. This study aims to investigate the role of SNF5 and its correlation with clinicopathologic characteristics in EC.

Methods

We performed immunohistochemistry to detect the SNF5 expression in 46 endometrial carcinomas and 20 normal endometrium (non-EC) specimens, as well as analyzed the correlations between SNF5 expression and clinicopathologic features of patients using a statistics software (GraphPad Prism V6.0). Western blotting had been used to confirm the protein level of SNF5 in endometrial tissues. In addition, we evaluated the correlations between SNF5 and p21 in EC.

Results

The positive immunostaining rate for SNF5 in EC and non-EC specimens were 65% (30/46) and 25% (5/20) respectively, and the expression of SNF5 was dramatically increased in EC compared with the normal endometrium (P < 0.01). The overexpression of SNF5 was associated with the PR levels, but not with age, FIGO stage, grade, lymphatic metastasis, myometrial invasion or ER status. Knockdown of SNF5 inhibits the expression of p21.

Conclusions

Our results indicate that SNF5 plays an important role of promoting oncogenesis in EC. These findings open up the possibility for various novel and effective combination therapies targeting SNF5 in the EC.

Mifepristone inhibits proliferation, migration and invasion of HUUA cells and promotes its apoptosis by regulation of FAK and PI3K/AKT signaling pathway

Purpose

The aim was to investigate mifepristone effects on endometrial carcinoma and the related mechanism.

Methods

HHUA cells were treated with DMEM containing different concentrations of mifepristone. HHUA cells treated with 100 μmol/L mifepristone were named the Mifepristone group. HHUA cells co-transfected with pcDNA3.1-PI3K and pcDNA3.1-AKT overexpression vectors were treated with 100 μmol/L mifepristone and named the Mifepristone + PI3K/AKT group. mRNA expression was detected by quantitative reverse transcription PCR. Protein expression was performed by Western blot. Cell proliferation was conducted by MTT assay. Wound-healing assay was conducted. Transwell was used to detect cells migration and invasion. Apoptosis detection was performed by flow cytometry.

Results

Mifepristone inhibited HHUA cells proliferation in a dose-dependent manner. Compared with HHUA cells treated with 0 μmol/L mifepristone, HHUA cells treated by 50–100 μmol/L mifepristone had a lower wound-healing rate, a greater number of migrating and invasive cells (P<0.01), as well as a higher percentage of apoptotic cells and Caspase-3 expression (P<0.01). When HHUA cells were treated with 50–100 μmol/L of mifepristone, FAK, p-FAK, p-PI3K and p-AKT relative expression was all significantly lower than HHUA cells treated with 0 μmol/L of mifepristone (P<0.01). Compared with the Mifepristone group, HHUA cells of the Mifepristone + PI3K/AKT group had a lower cell growth inhibition rate and percentage of apoptotic cells (P<0.01).

Conclusion

Mifepristone inhibited HUUA cells proliferation, migration and invasion and promoted its apoptosis by regulation of FAK and PI3K/AKT signaling pathway.