High SOX8 expression promotes tumor growth and predicts poor prognosis through GOLPH3 signaling in tongue squamous cell carcinoma

SRY-Related Transcription Factors in Head and Neck Squamous Cell Carcinomas: In Silico Based Analysis

Head and neck squamous cell carcinoma (HNSCC) is the sixth leading cancer and the fifth cause of cancer-related deaths worldwide with a poor 5-year survival. SOX family genes play a role in the processes involved in cancer development such as epithelial-mesenchymal transition (EMT), the maintenance of cancer stem cells (CSCs) and the regulation of drug resistance. We analyzed the expression of SOX2-OT, SOX6, SOX8, SOX21, SOX30 and SRY genes in HNSCC patients using the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets, to assess their biological role and their potential utility as biomarkers. We demonstrated statistically significant differences in expression between normal and primary tumor tissues for SOX6, SOX8, SOX21 and SOX30 genes and pointed to SOX6 as the one that met the independent diagnostic markers criteria. SOX21 or SRY alone, or the panel of six SRY-related genes, could be used to estimate patient survival. SRY-related genes are positively correlated with immunological processes, as well as with keratinization and formation of the cornified envelope, and negatively correlated with DNA repair and response to stress. Moreover, except SRY, all analyzed genes were associated with a different tumor composition and immunological profiles. Based on validation results, the expression of SOX30 is higher in HPV(+) patients and is associated with patients' survival. SRY-related transcription factors have vast importance in HNSCC biology. SOX30 seems to be a potential biomarker of HPV infection and could be used as a prognostic marker, but further research is required to fully understand the role of SOX family genes in HNSCC.

Crucial role of the transcription factors family activator protein 2 in cancer: current clue and views

The transcription factor family activator protein 2 (TFAP2) is vital for regulating both embryonic and oncogenic development. The TFAP2 family consists of five DNA-binding proteins, including TFAP2A, TFAP2B, TFAP2C, TFAP2D and TFAP2E. The importance of TFAP2 in tumor biology is becoming more widely recognized. While TFAP2D is not well studied, here, we mainly focus on the other four TFAP2 members. As a transcription factor, TFAP2 regulates the downstream targets directly by binding to their regulatory region. In addition, the regulation of downstream targets by epigenetic modification, posttranslational regulation, and interaction with noncoding RNA have also been identified. According to the pathways in which the downstream targets are involved in, the regulatory effects of TFAP2 on tumorigenesis are generally summarized as follows: stemness and EMT, interaction between TFAP2 and tumor microenvironment, cell cycle and DNA damage repair, ER- and ERBB2-related signaling pathway, ferroptosis and therapeutic response. Moreover, the factors that affect TFAP2 expression in oncogenesis are also summarized. Here, we review and discuss the most recent studies on TFAP2 and its effects on carcinogenesis and regulatory mechanisms.

Downregulation of Sox8 mediates monosodium urate crystal-induced autophagic impairment of cartilage in gout arthritis

The deposition of monosodium urate (MSU) crystals in arthritic joints of gout seriously damages cartilage. This study aimed to investigate whether MSU crystal-induced cartilage impairment was related to autophagic signaling. mRNAs of cartilage from MSU-induced gouty arthritis rat model were sequenced. MSU crystal-treated human chondrocytes were used to evaluate the function of Sox8. The recombinant Sox8 lentiviral vector (lenti-Sox8) was applied to upregulate the expression of Sox8. Transfection of the mRFP-GFP-LC3 plasmid was evaluated by confocal microscopy. The autophagic vacuoles were stained with monodansylcadaverine and examined by flow cytometry. The morphology of autophagosomes was observed by transmission electron microscopy. The ratio of LC3-II/I in the presence or absence of bafilomycin A1 and the expression levels of Beclin1, Sox8, p-PI3K, PI3K, p-AKT, AKT, p-mTOR, and mTOR were detected by Western blot. In vivo, the effect of Sox8 on cartilage of acute gouty model rats was evaluated by safranin-O/fast green staining and Western blot. The expression of Sox8 was significantly downregulated both in vivo and in vitro. In chondrocytes, MSU crystals reduced the expression of Sox8, inhibited the PI3K/AKT/mTOR signaling pathway, and increased the level of autophagy. Overexpression of Sox8 notably inhibited MSU crystal-induced autophagy by rescuing the phosphorylation levels in the PI3K/AKT/mTOR signaling pathway. In vivo, overexpression of Sox8 remarkably alleviated cartilage damage in acute gouty model rats. These results indicate that downregulation of Sox8 plays an important role in MSU-induced chondrocyte autophagy by modulating PI3K/AKT/mTOR signaling, and overexpression of Sox8 may serve as a novel therapy to prevent the impairment of cartilage in gout arthritis.

Influence of the Postmortem/Storage Time of Human Corneas on the Properties of Cultured Limbal Epithelial Cells

Besides being a powerful model to study the mechanisms of corneal wound healing, tissue-engineered human corneas (hTECs) are sparking interest as suitable substitutes for grafting purposes. To ensure the histological and physiological integrity of hTECs, the primary cultures generated from human cornea (identified as human limbal epithelial cells (hLECs) that are used to produce them must be of the highest possible quality. The goal of the present study consisted in evaluating the impact of the postmortem/storage time (PM/ST) on their properties in culture. hLECs were isolated from the entire cornea comprising the limbus and central cornea. When grown as monolayers, short PM/ST hLECs displayed increased daily doublings and generated more colonies per seeded cells than long PM/ST hLECs. Moreover, hLECs with a short PM/ST exhibited a markedly faster wound closure kinetic both in scratch wound assays and hTECs. Collectively, these results suggest that short PM/ST hLECs have a greater number of highly proliferative stem cells, exhibit a faster and more efficient wound healing response in vitro, and produce hTECs of a higher quality, making them the best candidates to produce biomaterial substitutes for clinical studies.

Linc00467 promotes invasion and inhibits apoptosis of head and neck squamous cell carcinoma by regulating miR-1285-3p/TFAP2A

OBJECTIVE

To explore the invasion and apoptosis of head and neck squamous cell carcinoma (HNSCC) regulated by Linc00467 through the miR-1285-3p/TFAP2A axis.

METHODS

qRT-PCR was used to detect the expressions of Linc00467, miR-1285-3p, and TFAP2A in tissues and cells of HNSCC patients. The targeting relationships between Linc00467 and miR-1285-3p, miR-1285-3p, and TFAP2A were verified by dual-luciferase reporter assay. Transfection and grouping were carried out, after HNSCC cell lines were screened. Transwell assay and flow cytometry were used to test cell invasion and apoptosis, respectively.

RESULTS

Compared with normal tissues adjacent to the tumor, the expressions of Linc00467 and TFAP2A increased significantly in cancer tissues, while the expression of miR-1285-3p decreased (all P<0.05). Compared with the si-NC group, the invasion of the si-Linc00467 group decreased and the apoptosis rate increased (both P<0.05). In HNSCC cells, over-expression of Linc00467 promoted increased cell invasion and decreased apoptosis rate, which could be partially rescued by over-expression of miR-1285-3p (all P<0.05). Over-expression of miR-1285-3p caused decreased cell invasion and increased apoptosis rate, which was partially reversed by over-expression of TFAP2A (all P<0.05).

CONCLUSION

Linc00467 can be used as ceRNA to adsorb miR-1285-3p to regulate the expression of TFAP2A, promote invasion and inhibit apoptosis of HNSCC cells. Linc00467 inhibitors may become one of the targeted therapeutic drugs for HNSCC.

The role of SOX family transcription factors in gastric cancer

Gastric cancer (GC) is a leading cause of death worldwide. GC is the third-most common cause of cancer-related death after lung and colorectal cancer. It is also the fifth-most commonly diagnosed cancer. Accumulating evidence has revealed the role of signaling networks in GC progression. Identification of these molecular pathways can provide new insight into therapeutic approaches for GC. Several molecular factors involved in GC can play both onco-suppressor and oncogene roles. Sex-determining region Y (Sry)-box-containing (SOX) family members are transcription factors with a well-known role in cancer. SOX proteins can bind to DNA to regulate cellular pathways via a highly conserved domain known as high mobility group (HMG). In the present review, the roles of SOX proteins in the progression and/or inhibition of GC are discussed. The dual role of SOX proteins as tumor-promoting and tumor-suppressing factors is highlighted. SOX members can affect upstream mediators (microRNAs, long non-coding RNAs and NF-κB) and down-stream mediators (FAK, HIF-1α, CDX2 and PTEN) in GC. The possible role of anti-tumor compounds to target SOX pathway members in GC therapy is described. Moreover, SOX proteins may be used as diagnostic or prognostic biomarkers in GC.

MicroRNA-139 Suppresses the Tumorigenicity of Triple Negative Breast Cancer Cells by Targeting SOX8

Purpose

The effects of miR-139 on the tumorigenicity of triple negative breast cancer (TNBC) and the underlying mechanisms were investigated.

Methods

Normal human breast epithelial (MCF-10A) and TNBC cell lines (HCC1806 and BT549) were used for microRNA (miR)-139 overexpression, SOX8 overexpression, and knockdown studies as in vitro models of TNBC. The expression of SOX8 and miR-139 was detected by reverse transcription-polymerase chain reaction. CCK8 and clone formation assays were used to evaluate cell proliferation ability. Transwell assays and flow cytometry were used to test cell migration and apoptosis, respectively. Cell tumorigenicity was examined by tumor sphere formation assays. The interaction between miR-139 and SOX8 was examined by dual-luciferase reporter assays. The expression of SOX8, cleaved caspase-3, and cleaved caspase-9 was analyzed by Western blotting. The findings were validated in vivo using a nude mouse transplanted tumor model.

Results

SOX8 expression was higher (P < 0.05) and miR-139 expression was lower (P < 0.05) in HCC1806 and BT549 cells than in MCF-10A cells. SOX8 overexpression significantly enhanced cell proliferation and migration, reduced the rate of cell apoptosis, and increased tumor sphere formation (P < 0.05) compared with the control group, whereas SOX8 knockdown had the opposite effect (P < 0.05). Overexpression of miR-139 markedly decreased cell proliferation and migration, increased cell apoptosis in vitro, and decreased tumor angiogenesis and volume in vivo (P < 0.05).

Conclusion

miR-139 suppressed the tumorigenicity of TNBC cells by targeting SOX8.

High SOX8 expression promotes tumor growth and predicts poor prognosis through GOLPH3 signaling in tongue squamous cell carcinoma

According to our previous study, GOLPH3 is markedly up-expressed in tongue squamous cell carcinoma (TSCC), which is also associated with poor survival. However, it remains unclear about key upstream and downstream mechanisms of GOLPH3. This study aimed to illuminate new mechanisms modulating GOLPH3 upregulation and promoting TSCC development at the molecular level. Using mass spectrometry and agarose-streptavidin-biotin pull-down analyses, SOX8 (SRY-Box 8) was identified to be the new protein to bind the GOLPH3 promoter within TSCC cells, which was further verified to be the regulator of GOLPH3 upregulation. The knockdown of SOX8 suppressed the promoter activity of GOLPH3, while secondarily inhibiting TSCC cell proliferation both in vivo and in vitro. Interestingly, GOLPH3 overexpression rescued the SOX8 knockdown-mediated suppression on TSCC proliferation. Additionally, exogenous over-expression of SOX8 also activated the activity of promoter as well as GOLPH3 expression, in the meantime of promoting TSCC development. Moreover it was discovered that SOX8 regulated GOLPH3 expression through interacting with TFAP2A. Moreover our results suggested that the SOX8 level was increased within tumor tissue compared with that in para-cancer normal counterpart, which showed positive correlation with the GOLPH3 level. According to Kaplan-Meier analyses, TSCC cases having higher SOX8 and GOLPH3 expression were associated with poorer prognostic outcomes. Taken together, this study reveals that SOX8 enhances the TSCC cell growth via the direct transcriptional activation of GOLPH3, which also indicates the potential to use SOX8/GOLPH3 pathway as the treatment target among TSCC patients.