The cross-regulation between SOX15 and Wnt signaling pathway

Cross-regulation between SOX9 and the canonical Wnt signalling pathway in stem cells

SOX9, a member of the SRY-related HMG-box transcription factors, has been reported to critically regulate fetal development and stem cell homeostasis. Wnt signalling is a highly conserved signalling pathway that controls stem cell fate decision and stemness maintenance throughout embryonic development and adult life. Many studies have shown that the interactions between SOX9 and the canonical Wnt signalling pathway are involved in many of the physiological and pathological processes of stem cells, including organ development, the proliferation, differentiation and stemness maintenance of stem cells, and tumorigenesis. In this review, we summarize the already-known molecular mechanism of cross-interactions between SOX9 and the canonical Wnt signalling pathway, outline its regulatory effects on the maintenance of homeostasis in different types of stem cells, and explore its potential in translational stem cell therapy.

Significance of miRNAs on the thyroid cancer progression and resistance to treatment with special attention to the role of cross-talk between signaling pathways

Thyroid cancer (TC) is the most prevalent endocrine malignant tumor. It has many types, the Papillary thyroid cancer (PTC)(most common and follicular thyroid carcinoma (FTC). Several risk factors have been associated with TC radiation exposure, autoimmunity, and genetics. Microribonucleic acids (miRNAs) are the most important genetic determinants of TC. They are small chains of nucleic acids that are able to inhibit the expression of several target genes. They could target several genes involved in TC proliferation, angiogenesis, apoptosis, development, and even resistance to therapy. Besides, they could influence the stemness of TC. Moreover, they could regulate several signaling pathways such as WNT/β-catenin, PI3K/AKT/mTOR axis, JAK/STAT, TGF- β, EGFR, and P53. Besides signaling pathways, miRNAs are also involved in the resistance of TC to major treatments such as surgery, thyroid hormone-inhibiting therapy, radioactive iodine, and adjuvant radiation. The stability and sensitivity of several miRNAs might be exploited as an approach for the usage of miRNAs as diagnostic and/or prognostic tools in TC.

SOX transcription factors direct TCF-independent WNT/β-catenin responsive transcription to govern cell fate in human pluripotent stem cells

WNT/β-catenin signaling controls gene expression across biological contexts from development and stem cell homeostasis to diseases including cancer. How β-catenin is recruited to distinct enhancers to activate context-specific transcription is unclear, given that most WNT/ß-catenin-responsive transcription is thought to be mediated by TCF/LEF transcription factors (TFs). With time-resolved multi-omic analyses, we show that SOX TFs can direct lineage-specific WNT-responsive transcription during the differentiation of human pluripotent stem cells (hPSCs) into definitive endoderm and neuromesodermal progenitors. We demonstrate that SOX17 and SOX2 are required to recruit β-catenin to lineage-specific WNT-responsive enhancers, many of which are not occupied by TCFs. At TCF-independent enhancers, SOX TFs establish a permissive chromatin landscape and recruit a WNT-enhanceosome complex to activate SOX/ß-catenin-dependent transcription. Given that SOX TFs and the WNT pathway are critical for specification of most cell types, these results have broad mechanistic implications for the specificity of WNT responses across developmental and disease contexts.

SOX15 transcriptionally increases the function of AOC1 to modulate ferroptosis and progression in prostate cancer

Amine oxidase copper-containing 1 (AOC1) is considered an oncogene in many types of tumors. Nevertheless, there have been no investigations of AOC1 and its regulatory mechanism in prostate cancer. Here, we reveal a novel action of AOC1 and a tumor suppressor mechanism in prostate cancer. AOC1 is downregulated in prostate cancer. Abatement of AOC1 in prostate cancer tissue is positively correlated with the tumor size, lymph node metastasis, and Gleason score for prostate cancer. Conversely, high expression of AOC1 is significantly associated with reduced proliferation and migration in prostate cancer both in vitro and in vivo. We show that the anticancer effect of AOC1 is mediated by its action on spermidine which leads to the activation of reactive oxygen species and ferroptosis. AOC1 expression in prostate cancer is positively regulated by the transcription factor SOX15. Therefore, SOX15 can transcriptionally promote AOC1 expression and strengthen this effect. Targeting AOC1 and SOX15 may be promising for the treatment of prostate cancer.

Sox15 Methylation Inhibits Cell Proliferation Through Wnt Signaling in Hepatocellular Carcinoma

The expression of the SRY-Box Transcription Factor 15 (Sox15) is reduced by DNA methylation, and its progression is suppressed within numerous tumors. However, its effect on hepatocellular carcinoma (HCC) remains unknown. In the present work, the clinical importance and function of Sox15, as well as the underlying molecular mechanism, were explored within HCC. The expression of Sox15 is reduced and positively correlated with prognosis in HCC as analyzed by GEPIA (Gene Expression Profiling Interactive Analysis) and OncoLnc. Meanwhile, the hypermethylated Sox15 promoter CpG-site predicted a dismal HCC prognosis. Besides, ectopic Sox15 expression within the HCC cells (LM3, HUH7, SK-hep-1) remarkably inhibited in vitro cell growth and inhibited xenograft tumorigenesis in the nude mice. Moreover, Sox15 inactivated the Wnt pathway under both in vivo and in vitro conditions. To summarize, Sox15 played a tumor suppressor role within the HCC via the inactivated Wnt pathway. Sox15 and CpG-site methylation of its promoter are the factors that independently predict the prognosis of HCC.

Barrett's Metaplasia Progression towards Esophageal Adenocarcinoma: An Attempt to Select a Panel of Molecular Sensors and to Reflect Clinical Alterations by Experimental Models

The molecular processes that predispose the development of Barrett’s esophagus (BE) towards esophageal adenocarcinoma (EAC) induced by gastrointestinal reflux disease (GERD) are still under investigation. In this study, based on a scientific literature screening and an analysis of clinical datasets, we selected a panel of 20 genes covering BE- and EAC-specific molecular markers (FZD5, IFNGR1, IL1A, IL1B, IL1R1, IL1RN, KRT4, KRT8, KRT15, KRT18, NFKBIL1, PTGS1, PTGS2, SOCS3, SOX4, SOX9, SOX15, TIMP1, TMEM2, TNFRSF10B). Furthermore, we aimed to reflect these alterations within an experimental and translational in vitro model of BE to EAC progression. We performed a comparison between expression profiles in GSE clinical databases with an in vitro model of GERD involving a BE cell line (BAR-T) and EAC cell lines (OE33 and OE19). Molecular responses of cells treated with acidified bile mixture (BM) at concentration of 100 and 250 μM for 30 min per day were evaluated. We also determined a basal mRNA expression within untreated, wild type cell lines on subsequent stages of BE and EAC development. We observed that an appropriately optimized in vitro model based on the combination of BAR-T, OE33 and OE19 cell lines reflects in 65% and more the clinical molecular alterations observed during BE and EAC development. We also confirmed previous observations that exposure to BM (GERD in vitro) activated carcinogenesis in non-dysplastic cells, inducing molecular alternations in the advanced stages of BE. We conclude that it is possible to induce, to a high extent, the molecular profile observed clinically within appropriately and carefully optimized experimental models, triggering EAC development. This experimental scheme and molecular marker panel might be implemented in further research, e.g., aiming to develop and evaluate novel compounds and prodrugs targeting GERD as well as BE and EAC prevention and treatment.

Comprehensive analysis of R-spondin fusions and RNF43 mutations implicate novel therapeutic options in colorectal cancer

PURPOSE

Gene fusions involving R-spondin (RSPOfp) and RNF43 mutations have been shown to drive Wnt-dependent tumor initiation in colorectal cancer (CRC). Herein, we aimed to characterize the molecular features of RSPOfp/RNF43 mutated (mut) compared to wildtype CRCs to gain insights into potential rationales for therapeutic strategies.

EXPERIMENTAL DESIGN

A discovery cohort was classified for RSPOfp/RNF43 status using DNA/RNA sequencing and immunohistochemistry. An independent cohort was used to validate our findings.

RESULTS

The discovery cohort consisted of 7,245 CRC samples. RSPOfp and RNF43 mutations were detected in 1.3% (n=94) and 6.1% (n=443) of cases. We found 5 RSPO fusion events that had not previously been reported (e.g. IFNGR1-RSPO3). RNF43-mut tumors were associated with right-sided primary tumors. No RSPOfp tumors had RNF43 mutations. In comparison to wildtype CRCs, RSPOfp tumors were characterized by a higher frequency of BRAF, BMPR1A and SMAD4 mutations. APC mutations were observed in only a minority of RSPOfp-positive compared to wildtype cases (4.4 vs. 81.4%). Regarding RNF43 mutations, a higher rate of KMT2D and BRAF mutations were detectable compared to wildtype samples. While RNF43 mutations were associated with a microsatellite instability (MSI-H)/mismatch repair deficiency (dMMR) phenotype (64.3%), and a TMB {greater than or equal to}10 mt/Mb (65.8%), RSPOfp was not associated with MSI-H/dMMR. The validation cohort replicated our genetic findings.

CONCLUSIONS

This is the largest series of RSPOfp/RNF43-mut CRCs reported to date. Comprehensive molecular analyses asserted the unique molecular landscape associated with RSPO/RNF43 and suggested potential alternative strategies to overcome the low clinical impact of Wnt-targeted agents and immunotherapy.

Inhibition of SOX15 Sensitizes Esophageal Squamous Carcinoma Cells to Paclitaxel

BACKGROUND

SOX15 is a crucial transcription factor involved in the regulation of embryonic development and in the cell fate determination. It is also an important mediator of tumorigenesis in cancer.

METHODS

Here, we sought to explore the expression patterns and biological functions of SOX15 in esophageal squamous cell carcinomas (ESCC). SOX15 was found aberrantly overexpressed in ESCC tumors.

RESULTS

Experimentally, inhibition of SOX15 through RNAi suppressed cell proliferation in ESCC cells and sensitized cancer cells to paclitaxel, but not to Cisplatin. Moreover, inhibition of SOX15 significantly repressed the expression of genes associated with WNT and NOTCH signaling pathways, which may contribute to the increased sensitivity to paclitaxel.

CONCLUSION

In conclusion, the current study revealed that inhibition of SOX15 in ESCC cells sensitizes the ESCC cells to paclitaxel, suggesting that the SOX15 expression level may predict the therapeutic outcomes for paclitaxel treatment for ESCC.

Neratinib decreases pro-survival responses of [sorafenib + vorinostat] in pancreatic cancer

The combination of the multi-kinase and chaperone inhibitor sorafenib and the histone deacetylase inhibitor vorinostat in pancreatic cancer patients has proven to be a safe and efficacious modality (NCT02349867). We determined the evolutionary mechanisms by with pancreatic tumors become resistant to [sorafenib + vorinostat] and developed a new three-drug therapy to circumvent the resistant phenotype. Pancreatic tumors previously exposed to [sorafenib + vorinostat] evolved to activate the receptors ERBB1, ERBB2, ERBB3, c-MET and the intracellular kinase AKT. The irreversible ERBB receptor family and MAP4K inhibitor neratinib significantly enhanced the anti-tumor efficacy of [sorafenib + vorinostat]. We then determined the mechanisms by which neratinib enhanced the efficacy of [sorafenib + vorinostat]. Compared to [sorafenib + vorinostat] or to neratinib alone, the three-drug combination further enhanced the phosphorylation of eIF2α and NFκB and the expression of Beclin1, ATG5 and CD95; and suppressed the levels of β-catenin. Knock down of Beclin1, ATG5, CD95, eIF2 α or NFκB suppressed cell killing whereas knock down of β-catenin enhanced killing. The drugs interacted to increase autophagosome formation; and autophagy and cell killing were suppressed by expression of activated mTOR. A portion of the killing mechanism required CD95 signaling and knock down of NFκB prevented the drugs from increasing CD95 expression. We conclude that neratinib, by down-regulation of evolutionary activated growth factor receptors, may represent a novel follow-on clinical concept after the completion of NCT02349867.

SOX15 exerts antitumor function in glioma by inhibiting cell proliferation and invasion via downregulation of Wnt/β-catenin signaling

AIMS

Sex-determining region of Y chromosome-related high-mobility-group box 15 (SOX15) has recently emerged as a candidate tumor-inhibitor in multiple types of human tumors. To date, the involvement of SOX15 in glioma is undetermined. The purpose of this study was to investigate the expression, function and potential molecular mechanism of SOX15 in glioma.

MAIN METHODS

Relative mRNA expression was analyzed by real-time quantitative PCR. Protein expression was determined by Western blot. Cell proliferation was assessed by cell counting kit-8 and colony formation assay. Cell invasion was evaluated by Matrigel invasion assay. Wnt/β-catenin activation was monitored by luciferase reporter assay.

KEY FINDINGS

SOX15 expression was decreased in glioma tissues and cell lines compared with normal controls. Kaplan-Meier analysis revealed that patients with low expression of SOX15 had shorter survival than those who had high expression of SOX15. The upregulation of SOX15 markedly repressed the proliferation and invasion of glioma cells, whereas its depletion enhanced glioma cell proliferation and invasion. Research into the mechanism revealed that SOX15 exerted an inhibitory effect on Wnt/β-catenin signaling in glioma cells. Notably, overexpression of β-catenin partially reversed the SOX15 overexpression-mediated tumor-suppressive effect. In addition, SOX15 overexpression significantly impeded tumor formation by glioma cells in vivo in a mouse xenograft model associated with downregulation of active β-catenin expression.

SIGNIFICANCE

These data demonstrate that SOX15 functions as a potential tumor-suppressor in glioma by inhibiting cell proliferation and invasion via the downregulation of Wnt/β-catenin signaling.

Downregulation of microR-147b represses the proliferation and invasion of thyroid carcinoma cells by inhibiting Wnt/β-catenin signaling via targeting SOX15

microRNA-147b (miR-147b) is a newly identified tumor-related miRNA that is dysregulated in multiple cancer types. Yet, the role of miR-147b in thyroid carcinoma remains unknown. Herein, we found that miR-147b expression was upregulated in thyroid carcinoma tissues and cell lines. miR-147b inhibition decreased the proliferation, colony formation, and invasion of thyroid carcinoma cells. The tumor suppressive gene SRY-related high-mobility-group box gene 15 (SOX15) was predicted as a miR-147b target gene. SOX15 expression was markedly decreased in thyroid carcinoma tissues and inversely correlated with the miR-147b expression. SOX15 overexpression repressed the proliferation and invasion of thyroid carcinoma cells associated with downregulation of Wnt/β-catenin signaling. SOX15 knockdown abolished the miR-147b-inhibition-mediated antitumor effect. miR-147b inhibition or SOX15 overexpression retarded the tumor growth of thyroid carcinoma cells in vivo. Overall, our study suggests that miR-147b inhibition restrains the proliferation and invasion of thyroid carcinoma cells through upregulation of SOX15 and inhibition of Wnt/β-catenin signaling.

SOX30, a target gene of miR-653-5p, represses the proliferation and invasion of prostate cancer cells through inhibition of Wnt/β-catenin signaling

Background

Sex-determining region Y-box containing gene 30 (SOX30) is a newly identified tumor-associated gene in several types of cancer. However, whether SOX30 is involved in the development and progression of prostate cancer remains unknown. This study investigated the potential role of SOX30 in prostate cancer.

Methods

Prostate cancer cell lines and a normal prostate epithelial cell line were used for the experiments. The expression of SOX30 was determined using quantitative real-time PCR and western blot analysis. The malignant cellular behaviors of prostate cancer were assessed using the Cell Counting Kit-8, colony formation and Matrigel invasion assays. The miRNA-mRNA interaction was validated using the dual-luciferase reporter assay.

Results

SOX30 expression was lower in cells of prostate cancer lines than in cells of the normal prostate epithelial line. Its overexpression repressed the proliferation and invasion of prostate cancer cells. SOX30 was identified as a target gene of microRNA-653-5p (miR-653-5p), which is upregulated in prostate cancer tissues. MiR-653-5p overexpression decreased SOX30 expression, while its inhibition increased SOX30 expression in prostate cancer cells. MiR-653-5p inhibition also markedly restricted prostate cancer cell proliferation and invasion. SOX30 overexpression or miR-653-5p inhibition significantly reduced β-catenin expression and downregulated the activation of Wnt/β-catenin signaling. SOX30 knockdown significantly reversed the miR-653-5p inhibition-mediated inhibitory effect on the proliferation, invasion and Wnt/β-catenin signaling in prostate cancer cells.

Conclusions

These results reveal a tumor suppressive function for SOX30 in prostate cancer and confirmed the gene as a target of miR-653-5p. SOX30 upregulation due to miR-653-5p inhibition restricted the proliferation and invasion of prostate cancer cells, and this was associated with Wnt/β-catenin signaling suppression. These findings highlight the importance of the miR-653-5p-SOX30-Wnt/β-catenin signaling axis in prostate cancer progression.

Testing the role of SOX15 in human primordial germ cell fate

Background: Potentially novel regulators of early human germline development have been identified recently, including SOX15 and SOX17, both of which show specific expression in human primordial germ cells. SOX17 is now known to be a critical specifier of human germ cell identity. There have been suggestions, as yet without evidence, that SOX15 might also play a prominent role. The early human germline is inaccessible for direct study, but an in vitro model of human primordial germ cell-like cell (hPGCLC) specification from human embryonic stem cells (hESCs) has been developed. This enables mechanistic study of human germ cell specification using genetic tools to manipulate the levels of SOX15 and SOX17 proteins to explore their roles in hPGCLC specification. Methods: SOX15 and SOX17 proteins were depleted during hPGCLC specification from hESCs using the auxin-inducible degron system, combined with a fluorescent reporter for tracking protein levels. Additionally, SOX15 protein was overexpressed using the ProteoTuner system. Protein-level expression changes were confirmed by immunofluorescence. The impact on hPGCLC specification efficiency was determined by flow cytometry at various time points. qPCR experiments were performed to determine some transcriptional effects of SOX15 perturbations. Results: We observed specific SOX15 expression in hPGCLCs by using immunofluorescence and flow cytometry analysis. Depletion of SOX15 had no significant effect on hPGCLC specification efficiency on day 4 after induction, but there was a significant and progressive decrease in hPGCLCs on days 6 and 8. By contrast, depletion of SOX17 completely abrogated hPGCLC specification. Furthermore, SOX15 overexpression resulted in a significant increase in hPGCLC fraction on day 8. qPCR analysis revealed a possible role for the germ cell and pluripotency regulator PRDM14 in compensating for changes to SOX15 protein levels. Conclusions: SOX17 is essential for hPGCLC specification, yet SOX15 is dispensable. However, SOX15 may have a role in maintaining germ cell identity.

Testing the role of SOX15 in human primordial germ cell fate

Background: Potentially novel regulators of early human germline development have been identified recently, including SOX15 and SOX17, both of which show specific expression in human primordial germ cells. SOX17 is now known to be a critical specifier of human germ cell identity. There have been suggestions, as yet without evidence, that SOX15 might also play a prominent role. The early human germline is inaccessible for direct study, but an in vitro model of human primordial germ cell-like cell (hPGCLC) specification from human embryonic stem cells (hESCs) has been developed. This enables mechanistic study of human germ cell specification using genetic tools to manipulate the levels of SOX15 and SOX17 proteins to explore their roles in hPGCLC specification. Methods: SOX15 and SOX17 proteins were depleted during hPGCLC specification from hESCs using the auxin-inducible degron system, combined with a fluorescent reporter for tracking protein levels. Additionally, SOX15 protein was overexpressed using the ProteoTuner system. Protein-level expression changes were confirmed by immunofluorescence. The impact on hPGCLC specification efficiency was determined by flow cytometry at various time points. qPCR experiments were performed to determine some transcriptional effects of SOX15 perturbations. Results: We observed specific SOX15 expression in hPGCLCs by using immunofluorescence and flow cytometry analysis. Depletion of SOX15 had no significant effect on hPGCLC specification efficiency on day 4 after induction, but there was a significant and progressive decrease in hPGCLCs on days 6 and 8. By contrast, depletion of SOX17 completely abrogated hPGCLC specification. Furthermore, SOX15 overexpression resulted in a significant increase in hPGCLC fraction on day 8. qPCR analysis revealed a possible role for the germ cell and pluripotency regulator PRDM14 in compensating for changes to SOX15 protein levels. Conclusions: SOX17 is essential for hPGCLC specification, yet SOX15 is dispensable. However, SOX15 may have a role in maintaining germ cell identity.

MicroRNA-140 inhibits skeletal muscle glycolysis and atrophy in endotoxin-induced sepsis in mice via the WNT signaling pathway

Sepsis is a systemic inflammatory response syndrome resulting from infection. This study aimed at exploring the role of microRNA-140 (miR-140) in septic mice. Wnt family member 11 (WNT11) was verified to be a target gene of miR-140 after bioinformatic prediction and dual luciferase reporter gene assay. Importantly, miR-140 negatively regulated WNT11. We initially induced the model of sepsis by endotoxin, and then ectopic expression and knockdown experiments were performed to explore the functional role of miR-140 in sepsis. Additionally, cross-sectional areas of muscle fiber, lactic acid production, 3-methylhistidine (3-MH) and tyrosine (Tyr) production in extensor digitorium longus (EDL) muscles, and serum levels of inflammatory factors were examined. The effect of miR-140 on the expression of WNT signaling pathway-related and apoptosis-related factors in skeletal muscle tissue was determined. The experimental results indicated that upregulated miR-140 or silenced WNT11 increased cross-sectional areas of muscle fiber while decreasing lactic acid production, skeletal muscle cell apoptosis [corresponding to downregulated B cell lymphoma 2 (Bcl-2)-associated X protein (Bax) and caspase-3 and upregulated Bcl-2], and the proteolytic rate of Tyr and 3-MH. Also, overexpressed miR-140 or silenced WNT11 reduced inflammation as reflected by decreased serum levels of IL-6, IL-10, and TNF-α. Furthermore, overexpression of miR-140 was shown to suppress the activation of the WNT signaling pathway, accompanied by decreased expression of WNT11, β-catenin, and GSK-3β. Taken together, upregulation of miR-140 could potentially inhibit skeletal muscle lactate release, an indirect measure of glycolysis, and atrophy in septic mice through suppressing the WNT signaling pathway via inhibiting WNT11 expression.

Detection for disease tipping points by landscape dynamic network biomarkers

A new model-free method has been developed and termed the landscape dynamic network biomarker (l-DNB) methodology. The method is based on bifurcation theory, which can identify tipping points prior to serious disease deterioration using only single-sample omics data. Here, we show that l-DNB provides early-warning signals of disease deterioration on a single-sample basis and also detects critical genes or network biomarkers (i.e. DNB members) that promote the transition from normal to disease states. As a case study, l-DNB was used to predict severe influenza symptoms prior to the actual symptomatic appearance in influenza virus infections. The l-DNB approach was then also applied to three tumor disease datasets from the TCGA and was used to detect critical stages prior to tumor deterioration using an individual DNB for each patient. The individual DNBs were further used as individual biomarkers in the analysis of physiological data, which led to the identification of two biomarker types that were surprisingly effective in predicting the prognosis of tumors. The biomarkers can be considered as common biomarkers for cancer, wherein one indicates a poor prognosis and the other indicates a good prognosis.

Knockdown of Sox2 Inhibits OS Cells Invasion and Migration via Modulating Wnt/β-Catenin Signaling Pathway

Osteosarcoma (OS) was a prevalent malignant bone tumor which threatens people's health worldwide. Wnt/β catenin signaling pathway had been proved significant in various cancers, indicating its possible function in OS as well. Sox2, a crucial member among SOX family could regulate cells biologically. How Sox2 modulated Wnt/β catenin signaling pathway in OS remained to be discussed. The study aimed to investigate the effects of Sox2 on the invasion and migration of OS cells and the related molecular mechanisms. Twenty-four human OS and adjacent tissue samples were involved in this study. Human OS cell lines MG63 and HOS were selected for further investigation. The liposome carrier si-Sox2 which could interfere with the expression of Sox2 gene was built to transfect MG63 and HOS cells). QRT-PCR assay and western blot were utilized to analyze the expression of mRNA and proteins of Sox2. Transwell assay and wound healing assay were conducted to test the invasion and migration level of cells. The expression of GSK3, β-catenin, cyclin D1 and c-myc proteins were detected by western blot assay after transfection with si-Sox2. Compared with normal tissues and cells, the expression of Sox2 in OS tissues and cells was significantly higher. The mRNA and protein levels of Sox2 significantly decreased after transfection with si-Sox2. The invasion and migration of OS cells were down-regulated significantly through the inhibition of Sox2 by inactivating Wnt/β-catenin signaling pathway related proteins. Knockdown of Sox2 could inhibit invasion and migration of OS cells via modulating Wnt/β-catenin signaling pathway.

Overexpression of SOX11 and TFE3 in Solid-Pseudopapillary Neoplasms of the Pancreas

OBJECTIVES

To characterize the expression of SOX11 and TFE3 proteins in solid-pseudopapillary neoplasms (SPNs) and their histologic mimickers.

METHODS

Immunohistochemistry for SOX11, TFE3, and β-catenin was performed on 31 cases of surgically resected SPNs. Neuroendocrine tumors, acinar cell carcinomas, and pancreatoblastomas served as controls.

RESULTS

Nuclear immunoreactivity for SOX11 was detected in all SPNs and five of 31 control tumors. Nuclear immunoreactivity for TFE3 was detected in 30 SPNs and three control tumors. Nuclear immunoreactivity for β-catenin was detected in all SPNs and four control tumors. The combination of three markers as immunohistochemical panels resulted in optimal sensitivity and specificity.

CONCLUSIONS

Both SOX11 and TFE3 were overexpressed in SPNs and may be involved in the pathogenesis. Clinically, SOX11 and TFE3 can be potentially used as diagnostic markers in distinguishing indeterminate SPNs from their histologic mimickers.

Curcumin Suppresses the Colon Cancer Proliferation by Inhibiting Wnt/β-Catenin Pathways via miR-130a

Curcumin exhibits anti-tumor effects in several cancers, including colorectal carcinoma (CRC), but the detailed mechanisms are still unclear. Here we studied the mechanisms underlying the anti-tumor effect of curcumin in colon cancer cells. SW480 cells were injected into mice to establish the xenograft tumor model, followed by evaluation of survival rate with the treatment of curcumin. The expression levels of β-catenin, Axin and TCF4 were measured in the SW480 cells in the absence or presence of curcumin. Moreover, miRNAs related to the curcumin treatment were also detected in vitro. Curcumin could suppress the growth of colon cancer cells in the mouse model. This anti-tumor activity of curcumin was exerted by inhibiting cell proliferation rather than promoting cell apoptosis. Further study suggested that curcumin inhibited cell proliferation by suppressing the Wnt/β-catenin pathway. MiR-130a was down-regulated by curcumin treatment, and overexpressing miR-130a could abolish the anti-tumor activity of curcumin. Our study confirms that curcumin is able to inhibit colon cancer by suppressing the Wnt/β-catenin pathways via miR-130a. MiR-130a may serve as a new target of curcumin for CRC treatment.

SOX15 regulates proliferation and migration of endometrial cancer cells

The study aimed to investigate the effects of Sry-like high mobility group box 15 (SOX15) on proliferation and migration of endometrial cancer (EC) cells. Immunohistochemistry (IHC) was applied to determine the expression of SOX15 in EC tissues and adjacent tissues. We used cell transfection method to construct the HEC-1-A and Ishikawa cell lines with stable overexpression and low expression SOX15. Reverse-transcription quantitative real-time PCR (RT-qPCR) and Western blot were performed to examine expression of SOX15 mRNA and SOX15 protein, respectively. By conducting a series of cell proliferation assay and migration assay, we analyzed the influence of SOX15 overexpression or low expression on EC cell proliferation and migration. The expression of SOX15 mRNA and protein in EC tissues was significantly lower than that in adjacent tissues. After lentivirus-transfecting SOX15, the expression level of SOX15 mRNA and protein was significantly increased in cells of SOX15 group, and decreased in sh-SOX15 group. Overexpression of SOX15 could suppress cell proliferation, while down-regulation of SOX15 increased cell proliferation. Flow cytometry results indicated that overexpression of SOX15 induced the ratio of cell-cycle arrest in G₁ stage. In addition, Transwell migration assay results showed that SOX15 overexpression significantly inhibited cell migration, and also down-regulation of SOX15 promoted the migration. As a whole, SOX15 could regulate the proliferation and migration of EC cells and up- regulation of SOX15 could be valuable for EC treatment.