High expression of Sox10 correlates with tumor aggressiveness and poor prognosis in human nasopharyngeal carcinoma

Clinical Significance of SOX10 Expression in Human Pathology

The embryonic development of neural crest cells and subsequent tissue differentiation are intricately regulated by specific transcription factors. Among these, SOX10, a member of the SOX gene family, stands out. Located on chromosome 22q13, the SOX10 gene encodes a transcription factor crucial for the differentiation, migration, and maintenance of tissues derived from neural crest cells. It plays a pivotal role in developing various tissues, including the central and peripheral nervous systems, melanocytes, chondrocytes, and odontoblasts. Mutations in SOX10 have been associated with congenital disorders such as Waardenburg-Shah Syndrome, PCWH syndrome, and Kallman syndrome, underscoring its clinical significance. Furthermore, SOX10 is implicated in neural and neuroectodermal tumors, such as melanoma, malignant peripheral nerve sheath tumors (MPNSTs), and schwannomas, influencing processes like proliferation, migration, and differentiation. In mesenchymal tumors, SOX10 expression serves as a valuable marker for distinguishing between different tumor types. Additionally, SOX10 has been identified in various epithelial neoplasms, including breast, ovarian, salivary gland, nasopharyngeal, and bladder cancers, presenting itself as a potential diagnostic and prognostic marker. However, despite these associations, further research is imperative to elucidate its precise role in these malignancies.

Insights into the molecular roles of FOXR2 in the pathology of primary pediatric brain tumors

Forkhead box gene R2 (FOXR2) belongs to the family of FOX genes which codes for highly conserved transcription factors (TFs) with critical roles in biological processes ranging from development to organogenesis to metabolic and immune regulation to cellular homeostasis. A number of FOX genes are associated with cancer development and progression and poor prognosis. A growing body of evidence suggests that FOXR2 is an oncogene. Studies suggested important roles for FOXR2 in cancer cell growth, metastasis, and drug resistance. Recent studies showed that FOXR2 is overexpressed by a subset of newly identified entities of embryonal tumors. This review discusses the role(s) FOXR2 plays in the pathology of pediatric brain cancers and its potential as a therapeutic target.

Immunohistological Expression of SOX-10 in Triple-Negative Breast Cancer: A Descriptive Analysis of 113 Samples

Background: SRY-related HMG-box 10 (SOX-10) is commonly expressed in triple negative breast cancer (TNBC). However, data on the biological significance of SOX-10 expression is limited. Therefore, we investigated immunhistological SOX-10 expression in TNBC and correlated the results with genetic alterations and clinical data. Methods: A tissue microarray including 113 TNBC cases was stained by SOX-10. Immunohistological data of AR, BCL2, CD117, p53 and Vimentin was available from a previous study. Semiconductor-based panel sequencing data including commonly altered breast cancer genes was also available from a previous investigation. SOX-10 expression was correlated with clinicopathological, immunohistochemical and genetic data. Results: SOX-10 was significantly associated with CD117 and Vimentin, but not with AR expression. An association of SOX-10 with BCL2, EGFR or p53 staining was not observed. SOX-10-positive tumors harbored more often TP53 mutations but less frequent mutations of PIK3CA or alterations of the PIK3K pathway. SOX-10 expression had no prognostic impact either on disease-free, distant disease-free, or overall survival. Conclusions: While there might be a value of SOX-10 as a differential diagnostic marker to identify metastases of TNBC, its biological role remains to be investigated.

TGF-β-induced long non-coding RNA MIR155HG promotes the progression and EMT of laryngeal squamous cell carcinoma by regulating the miR-155-5p/SOX10 axis

Non‑coding RNAs, particularly long non‑coding RNAs (lncRNAs), play important roles in tumorigenesis. The miR‑155 host gene (MIR155HG) lncRNA has been found to play a crucial role in tumor progression. However, the role of MIR155HG in laryngeal squamous cell carcinoma (LSCC) remains unclear. Thus, the aim of the present study was to explore the roles and underlying molecular mechanisms of action of MIR155HG and miR‑155‑5p in LSCC, in an effort to provide novel approaches for the antitumor therapy for LSCC. In the present study, the expression levels of miR‑155‑5p and MIR155HG were detected by reverse tran-scription‑quantitative polymerase chain reaction. In addition, the biological functions of MIR155HG and miR‑155‑5p on LSCC were evaluated in vitro by MTS assay, colony formation assay and Transwell assays, and in vivo by tumorigenesis assays. It was revealed that MIR155HG and miR‑155‑5p were significantly upregulated in LSCC tissues, and were associated with the TNM stage, pathological differentiation and lymph node metastasis. Moreover, the knockdown of MIR155HG and miR‑155‑5p inhibited the proliferation, migration and invasion of LSCC cells, whereas their overexpression exerted the opposite effects in vitro and MIR155HG overexpression promoted tumorigenesis in vivo. Furthermore, MIR155HG downregulation reduced the expression level of miR‑155‑5p. The inhibitory effect of MIR155HG knockdown on malignant behavior was abrogated by miR‑155‑5p overexpression. Bioinformatics analysis and luciferase reporter assay confirmed that miR‑155‑5p contributed to the progression of LSCC by directly binding to the 3' untranslated region of SRY‑related‑HMG‑box 10 (SOX10). In addition, MIR155HG and miR‑155‑5p were upregulated by the induction of transforming growth factor‑β (TGF‑β) and promoted the expression of mesenchymal markers synergistically. On the whole, the findings of the present study indicate a novel role of MIR155HG in the TGF‑β‑induced EMT of LSCC cells by regulating EMT markers through the miR‑155/SOX10 axis. The MIR155HG/miR‑155‑5p/SOX10 axis plays an important role in promoting the progression of LSCC and may thus serve as a potential therapeutic target for LSCC treatment.

Expression of HMB45, MelanA and SOX10 is rare in non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) and melanoma are frequent entities in routine diagnostics. Whereas the differential diagnosis is usually straight forward based on histomorphology, it can be challenging in poorly differentiated tumors as melanoma may mimic various histological patterns. Distinction of the two entities is of outmost importance as both are treated differently. HMB45 and MelanA are recommended immunohistological markers for melanoma in this scenario. SOX10 has been described as an additional marker for melanoma. However, comprehensive large-scale data about the expression of melanoma markers in NSCLC tumor tissue specimen are lacking so far.

METHODS

Therefore, we analyzed the expression of these markers in 1085 NSCLC tumor tissue samples. Tissue microarrays of NSCLC cases were immunohistochemically stained for HMB45, MelanA, and SOX10. Positivity of a marker was defined as ≥1% positive tumor cells.

RESULTS

In 1027 NSCLC tumor tissue samples all melanoma as well as conventional immunohistochemical markers for NSCLC could be evaluated. HMB45, MelanA, and SOX10 were positive in 1 (< 1%), 0 (0%) and 5 (< 1%) cases. The HMB45 positive case showed co-expression of SOX10 and was classified as large cell carcinoma. Three out of five SOX10 positive cases were SqCC and one case was an adenosquamous carcinoma.

CONCLUSIONS

Expression of HMB45, MelanA and SOX10 is evident but exceedingly rare in NSCLC cases. Together with conventional immunomarkers a respective marker panel allows a clear-cut differential diagnosis even in poorly differentiated tumors.

Clinicopathological, immunohistochemical and molecular correlation of neural crest transcription factor SOX10 expression in triple-negative breast carcinoma

The transcription factor SOX10 mediates the differentiation of neural crest-derived cells, and SOX10 by immunohistochemistry (IHC) is used primarily for the diagnosis of melanoma. SOX10 expression has been previously documented in benign breast myoepithelial cells. However there is limited literature on its expression in triple-negative breast carcinoma (TNBC). The aim was to study the clinical, pathologic and molecular profiles of SOX10+ tumors in TNBC. Tissue microarrays of TNBC were evaluated for SOX10 expression in 48 cases. SOX10 expression was correlated with clinical and pathologic features such as age, grade, and stage. Gene expression was analyzed on RNA extracted from formalin-fixed paraffin-embedded (FFPE) specimens with Affymetrix 2.0 HTA. Co-expression of SOX10 with androgen receptor (AR), WT1, gross cystic disease fluid protein-15 (GCDFP-15), mammaglobin, epidermal growth factor receptor (EGFR), CK5/6 and GATA transcription factor 3 (GATA3) were also assessed. The mean age was 59.38 (range, 28-90 years). Overall, 37.5% cases (18/48) were SOX10+. There was no association between SOX10 expression and age, grade or stage of patients; 6 of 10 (60%) cases of basal-like 1 (BL1), and 5 of 8 cases of unstable (UNS) molecular subtype were SOX10+. One of 5 basal-like-2 (BL2), 1 of 6 immunomodulatory (IM), 1 of 4 mesenchymal (M), 1 of 5 luminal androgen receptor (LAR) and 2 of 8 mesenchymal stem cell (MSL) showed lower frequencies of SOX10 expression. There was negative correlation between SOX10 and AR+ subtypes (P < .002). SOX10 was positively correlated with WT1 (P = .05). SOX10 did not show significant correlation with mammaglobin, GCDFP15, EGFR, CK5/6 and GATA3. SOX10 expression in the basal-like and unstable molecular subtypes supports the concept that these neoplasms show myoepithelial differentiation.

SOX10 induces epithelial-mesenchymal transition and contributes to nasopharyngeal carcinoma progression

OBJECTIVE

The aim of this study was to investigate the role of SOX10 in nasopharyngeal carcinoma (NPC) and the underlying molecular mechanisms.

METHODS

The expression of SOX10 was initially assessed in human NPC tissues and a series of NPC cell lines through quantitative real-time PCR (qRT-PCR) and Western blot. Then, cell proliferation, cycle, migration, and the invasiveness of NPC cells with knockdown of SOX10 were examined by MTT, flow cytometry, and Transwell migration and invasion assays, respectively. Finally, nude mice tumorigenicity experiments were performed to evaluate the effects of SOX10 on NPC growth and metastasis in vivo.

RESULTS

SOX10 was significantly increased in NPC tissues and cell lines. In-vitro experiments revealed that loss of SOX10 obviously inhibited cell proliferation, migration, and invasiveness, as well as the epithelial-mesenchymal transition (EMT) process in NPC cells. In-vivo experiments further demonstrated that disrupted SOX10 expression restrained NPC growth and metastasis, especially in lung and liver.

CONCLUSION

Taken together, our data confirmed the role of SOX10 as an oncogene in NPC progression, and revealed that SOX10 may serve as a novel biomarker for diagnosis of NPC, as well as a potential therapeutic target against this disease.

An autophagy-driven pathway of ATP secretion supports the aggressive phenotype of BRAFV600E inhibitor-resistant metastatic melanoma cells

The ingrained capacity of melanoma cells to rapidly evolve toward an aggressive phenotype is manifested by their increased ability to develop drug-resistance, evident in the case of vemurafenib, a therapeutic-agent targeting BRAF^V600E. Previous studies indicated a tight correlation between heightened melanoma-associated macroautophagy/autophagy and acquired Vemurafenib resistance. However, how this vesicular trafficking pathway supports Vemurafenib resistance remains unclear. Here, using isogenic human and murine melanoma cell lines of Vemurafenib-resistant and patient-derived melanoma cells with primary resistance to the BRAF^V600E inhibitor, we found that the enhanced migration and invasion of the resistant melanoma cells correlated with an enhanced autophagic capacity and autophagosome-mediated secretion of ATP. Extracellular ATP (eATP) was instrumental for the invasive phenotype and the expansion of a subset of Vemurafenib-resistant melanoma cells. Compromising the heightened autophagy in these BRAF^V600E inhibitor-resistant melanoma cells through the knockdown of different autophagy genes (ATG5, ATG7, ULK1), reduced their invasive and eATP-secreting capacity. Furthermore, eATP promoted the aggressive nature of the BRAF^V600E inhibitor-resistant melanoma cells by signaling through the purinergic receptor P2RX7. This autophagy-propelled eATP-dependent autocrine-paracrine pathway supported the maintenance and expansion of a drug-resistant melanoma phenotype. In conclusion, we have identified an autophagy-driven response that relies on the secretion of ATP to drive P2RX7-based migration and expansion of the Vemurafenib-resistant phenotype. This emphasizes the potential of targeting autophagy in the treatment and management of metastatic melanoma.