Study of antibodies to PMP22, IL-6 and TNF-alpha concentrations in serum in a CMTX1 family

High expression of EMP1 predicts a poor prognosis and correlates with immune infiltrates in bladder urothelial carcinoma

Epithelial membrane protein 1 (EMP1) is a key gene that regulates cell proliferation and metastatic capability in various types of cancer, and serves an important role in tumor-immune interactions. However, the association between EMP1 and clinical prognosis, as well as the presence of tumor-infiltrating lymphocytes in bladder urothelial carcinoma (BLCA) remains unclear. The present study aimed to explore the relationship between EMP1 expression and tumor immune cell infiltration in BLCA. In the present study, EMP1 expression in BLCA was analyzed using the Oncomine database, The Cancer Genome Atlas (TCGA) and the Tumor Immune Estimation Resource (TIMER). The effects of EMP1 on clinical prognosis were evaluated using the Kaplan-Meier plotter and Gene Expression Profiling Interactive Analysis. The correlations between EMP1, cancer immune infiltrates and lymphocyte abundance were determined using the TIMER and Tumor immune system interaction database. In addition, correlations between EMP1 expression and gene markers in immune infiltrates were analyzed using cBioportal. The results demonstrated that, compared with adjacent normal tissues, EMP1 was downregulated in BLCA tissues. High expression of EMP1 was significantly associated with poor overall survival (OS) in BLCA cases obtained from TCGA. Multivariate Cox analysis revealed that EMP1 was an independent predictor of OS in patients with BLCA. Gene set enrichment analysis revealed that EMP1 was associated with cancer-related pathways and was positively correlated with the levels of infiltrating CD8⁺ T cells, macrophages, neutrophils and dendritic cells in BLCA. Further analysis demonstrated that EMP1 was significantly associated with the enrichment of multiple types of lymphocyte. EMP1 expression exhibited a strong correlation with a range of immune markers in BLCA. In conclusion, the results of the present study demonstrated that EMP1 was associated with a poor prognosis in patients with BLCA, and that the levels of immune infiltration and multiple immunomarker groups were associated with EMP1 expression. These results suggested that EMP1 may be used as a predictive biomarker to determine the prognosis and immune infiltration in BLCA.

Aberrant trafficking of a Leu89Pro connexin32 mutant associated with X-linked dominant Charcot-Marie-Tooth disease

OBJECTIVE

To determine the functional abnormalities of the Leu89Pro mutation in connexin32 (CX32), which we have previously reported is present within an X-linked dominant Charcot-Marie-Tooth disease family. In this family, male patients were moderately to severely affected.

METHODS

We performed immunofluorescence to investigate whether the Leu89Pro CX32 protein was transported to the cell membrane in HeLa and Schwann cells. First, we constructed the eukaryotic express plasmids expressing CX32 (wild-type or Leu89Pro) and enhanced green fluorescent protein by the gene recombination technology. Then the recombinant plasmids were transiently transfected into communication-incompetent HeLa cells and human Schwann cells by the lipofectamine method. Later, we double-labeled cells for both CX32 and markers of the ER (calnexin) or the Golgi (58-kDa protein) at 24 h or 48 h. The images were collected using a Leica TCS SP5 II confocal microscope.

RESULTS

The mutant CX32 protein was localized in the endoplasmic reticulum and failed to reach the cell membrane to form gap junctions.

CONCLUSION

Our results indicated that the Leu89Pro substitution in the second transmembrane domain of CX32 disrupts the trafficking of the protein, inhibiting the assembly of CX32 gap junctions, which in turn may result in peripheral neuropathy. This functional abnormality may explain the moderate to severe phenotype seen in Leu89Pro patients, and as such represents a promising therapeutic target in the treatment of this subset of CMTX patients.