Elevated Levels of SOX10 in Serum from Vitiligo and Melanoma Patients, Analyzed by Proximity Ligation Assay

High expression of SOX10 is correlated with poor prognosis and immune infiltrates in skin cutaneous melanoma

Background

Skin Cutaneous Melanoma (SKCM) is a malignant tumor and the prediction of its prognosis remains challenging. Sex determining region Y-box 10 (SOX10) is over-expressed in SKCM and reported to accelerate tumor invasion and immunosuppression. Although studies have suggested the correlation of immune infiltration between SOX10 and SKCM, further in-depth explore of the immunomodulatory role of SOX10 is still needed. Therefore, we assessed the prognostic role of SOX10 and its correlation with immune infiltration and checkpoint expression.

Methods

RNA sequencing data were obtained for analysis of SOX10 expression and differentially expressed genes (DEGs) from the Cancer Genome Atlas (TCGA). Moreover, functional enrichment analysis of SOX10-related DEGs was performed by GO/KEGG, GSEA. Receiver operating characteristic (ROC) curves were used to assess the diagnostic value of SOX10 in SKCM. Kaplan-Meier method was conducted to assess the effect of SOX10 on survival. Additionally, the clinical significance of SOX10 in SKCM was figured out by LASSO and prognostic nomogram model. We analyzed SOX10-related immune cell infiltration and expression of immune checkpoints. Finally, validations were performed through immunohistochemical analysis.

Results

SOX10 was low expressed in a range of malignant tumor tissues except SKCM. Totally, 1029 differentially significant genes (DSGs) were identified between SOX10 low- and high- expression group, of which 50 genes were upregulated and 979 genes were downregulated. Additionally, SOX10 high expression was remarkably associated with pathologic stage, age and breslow depth in a sample of 472 cases (P < 0.05). Screening was performed by LASSO coefficients to select non-zero variables that satisfied the coefficients of lambda, and 8 genes were screened out. The forest plot results showed that only OCA2 and TRAT1 had statistical significance (P < 0.05) by multi-factor COX regression analysis. SOX10, OCA2, TRAT1, pathologic stage, age and breslow depth were included in the nomogram prognostic model. Furthermore, upregulation of SOX10 expression inhibited immune infiltration in SKCM.

Conclusion

Overall, high expression of SOX10 was correlated with poor prognosis in SKCM, which may be related to suppression of immune infiltration. The DSGs and pathways identified in our research have initially provided an insight into the molecular mechanisms underlying the progression of SKCM.

Identification of Upregulating Genes, Transcription Factors, and miRNAs in Vitiligo. In silico Study

Background

Depigmentation of specific areas of the skin is a persistent and long-lasting dermatologic disorder known as vitiligo, stemming from the impairment and disruption of melanocytes both structurally and functionally, leading to the loss of pigmentation in those regions.

Aim

Our objective was to identify the pivotal genes and upstream regulators, transcription factors (TFs), microRNAs (miRNAs), and pathways implicated in the pathogenesis of vitiligo.

Methods

An integrated analysis was conducted using microarray datasets on vitiligo obtained from the Gene Expression Omnibus (GEO) database. The functional annotation and potential pathways of differentially expressed genes (DEGs) were additionally investigated through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Various bioinformatics approaches were utilized, making use of publicly accessible databases to identify appropriate TFs and miRNAs.

Results

Our investigation identified TYR, MLANA, TYRP1, PMEL, OCA2, SLC45A2, GPR143, DCT, TRPM1, and EDNRB as the most appropriate genes associated with vitiligo. Our suggestion is that the identified biological processes include developmental pigmentation (GO:0048066) and pigment metabolic processes (GO:0042440) as the most suitable biological processes. In contrast, the KEGG pathways that showed significance in our analysis are Tyrosine metabolism (Path: hsa00350) and Melanogenesis (Path: hsa04916). We hypothesized the involvement of ten TFs and 73 miRNAs in the regulation of genes related to vitiligo.

Conclusion

TYR, MLANA, TYRP1, PMEL, OCA2, SLC45A2, GPR143, DCT, TRPM1, and EDNRB are the top ten genes that are pivotal in the progression and exhibition of vitiligo. The biological, cellular, molecular, and KEGG pathways of those genes has an imperative role in the pathogenesis of vitiligo. TFs and miRNAs that interact with this gene are listed, shedding light on the regulatory mechanisms governing the expression of these key genes in vitiligo.

Effect of vitiligo treatment by compound Glycyrrhizin combined with fractional laser and Triamcinolone Acetonide injection on T Lymphocyte subpopulation

OBJECTIVES

To discuss the effective mechanism of vitiligo treatment by compound glycyrrhizin combined with fractional laser and triamcinolone acetonide injection.

METHODS

Forty-two patients with vitiligo vulgaris in the stable phase were classified into combined group (19 cases) and medicine group (23) admitted in dermatology department, Baoding First Central Hospital from January 2017 to July 2018. Both groups took 50mg compound glycyrrhizin orally three times per day, and applied halometasone cream externally once per day. Based on this treatment method, after the combined group adopted fractional laser, triamcinolone acetonide injection encapsulation was used immediately. After the treatment for six months, the curative effect was judged for both groups. Flow cytometry was used to test the changes of T lymphocyte subpopulation in peripheral blood before and after treatment. Meanwhile, immunohistochemical method was adopted to determine CD4 + and CD8 + T lymphocyte expression level. Besides, the normal control group was set up.

RESULTS

The efficacy of combined group and medicine group were 73.68% and 56.52% respectively, P<0.05. The comparison of CD3 +, CD4 +, CD8 + and CD4 +/CD8 + T lymphocyte level in serum and skin damage before and after treatment had no statistical significance (P>0.05). Serum CD4 + T cells of vitiligo patients reduced, compared with the normal control group (P<0.05), and CD4 +/CD8 + declined (P<0.05). CD4 + and CD8 + T lymphocytes at the skin damage of patients increased, compared with normal control group (P<0.05).

CONCLUSIONS

Compound glycyrrhizin combined with fractional laser and triamcinolone acetonide injection has good clinical effect in the treatment of vitiligo vulgaris in the stable phase, and its effective mechanism may have nothing to do with T lymphocyte subpopulation.

Sex-Determining Region Y Chromosome-Related High-Mobility-Group Box 10 in Cancer: A Potential Therapeutic Target

Sex-determining region Y-related high mobility group-box 10 (SOX10), a member of the SOX family, has recently been highlighted as an essential transcriptional factor involved in developmental biology. Recently, the functionality of SOX 10 has been increasingly revealed by researchers worldwide. It has been reported that SOX10 significantly regulates the proliferation, migration, and apoptosis of tumors and is closely associated with the progression of cancer. In this review, we first introduce the basic background of the SOX family and SOX10 and then discuss the pathophysiological roles of SOX10 in cancer. Besides, we enumerate the application of SOX10 in the pathological diagnosis and therapeutic potential of cancer. Eventually, we summarize the potential directions and perspectives of SOX10 in neoplastic theranostics. The information compiled herein may assist in additional studies and increase the potential of SOX10 as a therapeutic target for cancer.

Interleukin 8 mediates bcl-xL-induced enhancement of human melanoma cell dissemination and angiogenesis in a zebrafish xenograft model

The protein bcl-xL is able to enhance the secretion of the proinflammatory chemokine interleukin 8 (CXCL8) in human melanoma lines. In this study, we investigate whether the bcl-xL/CXCL8 axis is important for promoting melanoma angiogenesis and aggressiveness in vivo, using angiogenesis and xenotransplantation assays in zebrafish embryos. When injected into wild-type embryos, bcl-xL-overexpressing melanoma cells showed enhanced dissemination and angiogenic activity compared with control cells. Human CXCL8 protein elicited a strong proangiogenic activity in zebrafish embryos and zebrafish Cxcr2 receptor was identified as the mediator of CXCL8 proangiogenic activity using a morpholino-mediated gene knockdown. However, human CXCL8 failed to induce neutrophil recruitment in contrast to its zebrafish homolog. Interestingly, the greater aggressiveness of bcl-xL-overexpressing melanoma cells was mediated by an autocrine effect of CXCL8 on its CXCR2 receptor, as confirmed by an shRNA approach. Finally, correlation studies of gene expression and survival analyses using microarray and RNA-seq public databases of human melanoma biopsies revealed that bcl-xL expression significantly correlated with the expression of CXCL8 and other markers of melanoma progression. More importantly, a high level of co-expression of bcl-xL and CXCL8 was associated with poor prognosis in melanoma patients. In conclusion, these data demonstrate the existence of an autocrine CXCL8/CXCR2 signaling pathway in the bcl-xL-induced melanoma aggressiveness, encouraging the development of novel therapeutic approaches for high bcl-xL-expressing melanoma.