SOX9 is expressed in human fetal prostate epithelium and enhances prostate cancer invasion

Overexpression of MicroRNA-138 Affects the Proliferation and Invasion of Urothelial Carcinoma Cells by Suppressing SOX9 Expression

SRY-box transcription factor 9 (SOX9) is important for sexual differentiation, chondrogenic differentiation, and cell proliferation in cancer. It acts as a target molecule of microRNA (miR)-138 in various tumors and is associated with tumor development and growth. In this study, we analyzed the functions of miR-138 and SOX9 in urothelial carcinoma. SOX9 was highly expressed in invasive urothelial carcinoma tissues. miR-138 precursor transfection of T24 and UMUC2 cells significantly decreased SOX9 expression, indicating that SOX9 is a miR-138 target in urothelial carcinoma. Moreover, miR-138 precursor or SOX9 small interfering RNA (siRNA) transfection decreased the proliferation of urothelial carcinoma cell lines. To further confirm that miR-138-SOX9 signaling is involved in cell proliferation and invasion, urothelial carcinoma cells were transfected with the miR-138 precursor or SOX9 siRNA. This transfection reduced the proliferation and invasion of cells via the promotion of autophagy and apoptosis and G0/G1 cell cycle arrest. These results suggest that miR-138-SOX9 signaling modulates the growth and invasive potential of urothelial carcinoma cells.

MicroRNA-155 and cancer metastasis: Regulation of invasion, migration, and epithelial-to-mesenchymal transition

Among the leading causes of death globally has been cancer. Nearly 90% of all cancer-related fatalities are attributed to metastasis, which is the growing of additional malignant growths out of the original cancer origin. Therefore, a significant clinical need for a deeper comprehension of metastasis exists. Beginning investigations are being made on the function of microRNAs (miRNAs) in the metastatic process. Tiny non-coding RNAs called miRNAs have a crucial part in controlling the spread of cancer. Some miRNAs regulate migration, invasion, colonization, cancer stem cells' properties, the epithelial-mesenchymal transition (EMT), and the microenvironment, among other processes, to either promote or prevent metastasis. One of the most well-conserved and versatile miRNAs, miR-155 is primarily distinguished by overexpression in a variety of illnesses, including malignant tumors. It has been discovered that altered miR-155 expression is connected to a number of physiological and pathological processes, including metastasis. As a result, miR-155-mediated signaling pathways were identified as possible cancer molecular therapy targets. The current research on miR-155, which is important in controlling cancer cells' invasion, and metastasis as well as migration, will be summarized in the current work. The crucial significance of the lncRNA/circRNA-miR-155-mRNA network as a crucial regulator of carcinogenesis and a player in the regulation of signaling pathways or related genes implicated in cancer metastasis will be covered in the final section. These might provide light on the creation of fresh treatment plans for controlling cancer metastasis.

SOX9 and HMGB3 co-operatively transactivate NANOG and promote prostate cancer progression

BACKGROUND

The homeodomain-containing transcription factor NANOG is overexpressed in prostate adenocarcinoma (PCa) and predicts poor prognosis. The SOX family transcription factor SOX9, as well as the transcription co-activator HMGB3 of the HMGB family, are also overexpressed and may play pivotal roles in PCa. However, it is unknown whether SOX9 and HMGB3 interact with each other, or if they regulate NANOG gene transcription.

METHODS

We identified potential SOX9 responsive elements in NANOG promoter, and investigated if SOX9 regulated NANOG transcription in co-operation with HMGB3 by experimental analysis of potential SOX9 binding sites in NANOG promoter, reporter gene transcription assays with or without interference or artificial overexpression of SOX9 and/or HMGB3, and protein-binding assays of SOX9-HMGB3 interaction. Clinicopathologic and prognostic significance of SOX9-HMGB3 overexpression in PCa was analyzed.

RESULTS

SOX9 activated NANOG gene transcription by preferentially binding to a highly conserved consensus cis-regulatory element (-573 to -568) in NANOG promoter, and promoted the expression of NANOG downstream oncogenic genes. Importantly, HMGB3 functioned as a partner of SOX9 to co-operatively enhance transactivation of NANOG by interacting with SOX9, predominantly via the HMG Box A domain of HMGB3. Overexpression of SOX9 and/or HMGB3 enhanced PCa cell survival and cell migration and were significantly associated with PCa progression. Notably, Cox proportional regression analysis showed that co-overexpression of both SOX9 and HMGB3 was an independent unfavorable prognosticator for both CRPC-free survival (relative risk [RR] = 3.779，95% confidence interval [CI]: 1.159-12.322, p = 0.028) and overall survival (RR = 3.615，95% CI: 1.101-11.876, p = 0.034).

CONCLUSIONS

These findings showed a novel SOX9/HMGB3/NANOG regulatory mechanism, deregulation of which played important roles in PCa progression.

Emerging Developments in ETS-Positive Prostate Cancer Therapy

Prostate cancer is a global health concern, which has a low survival rate in its advanced stages. Even though second-generation androgen receptor-axis inhibitors serve as the mainstay treatment options, utmost of the metastatic cases progress into castration-resistant prostate cancer after their initial treatment response with poor prognostic outcomes. Hence, there is a dire need to develop effective inhibitors that aim the causal oncogenes tangled in the prostate cancer initiation and progression. Molecular-targeted therapy against E-26 transformation-specific (ETS) transcription factors, particularly ETS-related gene, has gained wide attention as a potential treatment strategy. ETS rearrangements with the male hormone responsive transmembrane protease serine 2 promoter defines a significant number of prostate cancer cases and is responsible for cancer initiation and progression. Notably, inhibition of ETS activity has shown to reduce tumorigenesis, thus highlighting its potential as a clinical therapeutic target. In this review, we recapitulate the various targeted drug approaches, including small molecules, peptidomimetics, nucleic acids, and many others, aimed to suppress ETS activity. Several inhibitors have demonstrated ERG antagonist activity in prostate cancer, but further investigations into their molecular mechanisms and impacts on nontumor ETS-containing tissues is warranted.

Comprehensive analysis, immune, and cordycepin regulation for SOX9 expression in pan-cancers and the matched healthy tissues

SRY-box transcription factor 9 (SOX9) (OMIM 608160) is a transcription factor. The expression of SOX9 in pan-cancers and the regulation by small molecules in cancer cell lines are unclear. In the current study, we comprehensively analyzed the expression of SOX9 in normal tissues, tumor tissues and their matched healthy tissues in pan-cancers. The study examined the correlation between immunomodulators and immune cell infiltrations in normal and tumor tissues. Cordycepin (CD), an adenosine analog for SOX9 expression regulation, was also conducted on cancer cells. The results found that SOX9 protein is expressed in a variety of organs, including high expression in 13 organs and no expression in only two organs; in 44 tissues, there was high expression in 31 tissues, medium expression in four tissues, low expression in two tissues, and no expression in the other seven tissues. In pan-cancers with 33 cancer types, SOX9 expression was significantly increased in fifteen cancers, including CESC, COAD, ESCA, GBM, KIRP, LGG, LIHC, LUSC, OV, PAAD, READ, STAD, THYM, UCES, and UCS, but significantly decreased in only two cancers (SKCM and TGCT) compared with the matched healthy tissues. It suggests that SOX9 expression is upregulated in the most cancer types (15/33) as a proto-oncogene. The fact that the decrease of SOX9 expression in SKCM and the increase of SOX9 in the cell lines of melanoma inhibit tumorigenicity in both mouse and human ex vivo models demonstrates that SOX9 could also be a tumor suppressor. Further analyzing the prognostic values for SOX9 expression in cancer individuals revealed that OS is long in ACC and short in LGG, CESC, and THYM, suggesting that high SOX9 expression is positively correlated with the worst OS in LGG, CESC, and THYM, which could be used as a prognostic maker. In addition, CD inhibited both protein and mRNA expressions of SOX9 in a dose-dependent manner in 22RV1, PC3, and H1975 cells, indicating CD's anticancer roles likely via SOX9 inhibition. Moreover, SOX9 might play an important role in tumor genesis and development by participating in immune infiltration. Altogether, SOX9 could be a biomarker for diagnostics and prognostics for pan-cancers and an emerging target for the development of anticancer drugs.

Clinicopathological and prognostic significance of SOX9 expression in gastric cancer patients: A meta-analysis

BACKGROUND

SOX9 is a potential prognostic marker in gastric cancer (GC) patients. This meta-analysis aimed to highlight the clinicopathological and prognostic implications of SOX9 expression in GC patients.

METHODS

A systematic literature search was conducted to identify relevant studies by the electronic literature databases (PubMed, Web of Science, EMBASE and Chinese databases). Review Manager version 5.4 was employed to evaluate the pooled odds ratio (OR) or hazard ratio (HR) with 95% confidence intervals (CIs).

RESULTS

Seventeen studies with a total of 2893 GC patients were enrolled in this meta-analysis. The analysis with ten articles clarified that higher expression of SOX9 was observed in GC cancers than that of normal gastric samples (OR = 16.26; 95% CI: 8.16 to 32.42; P < .00001). Consequently, the results also showed that SOX9 expression was closely associated with age (OR = 1.34; 95% CI: 1.04-1.72; P = .03), tumor size (OR = 0.67; 95% CI: 0.49-0.91; P = .01), histological differentiation (OR = 0.62; 95% CI: 0.36-1.06; P = .002), tumor stage (OR = 0.48; 95% CI: 0.20-1.12; P = .04), lymph node metastasis (OR = 0.36; 95% CI: 0.19-0.67; P = .0010) and advanced TNM stage (OR = 0.46; 95% CI: 0.30-0.70; P = .0003), but not significantly related to gender, distant metastasis and vascular invasion. Furthermore, high SOX9 expression could significantly indicate poorer overall survival (OS) (HR = 1.40; 95% CI: 1.14-1.72; P = .001).

CONCLUSION

SOX9 overexpression might be related to poor prognosis and could serve as a potential predictive marker of poor clinicopathological prognosis factor in GC patients.

Effects of Multi-Omics Characteristics on Identification of Driver Genes Using Machine Learning Algorithms

Cancer is a complex disease caused by genomic and epigenetic alterations; hence, identifying meaningful cancer drivers is an important and challenging task. Most studies have detected cancer drivers with mutated traits, while few studies consider multiple omics characteristics as important factors. In this study, we present a framework to analyze the effects of multi-omics characteristics on the identification of driver genes. We utilize four machine learning algorithms within this framework to detect cancer driver genes in pan-cancer data, including 75 characteristics among 19,636 genes. The 75 features are divided into four types and analyzed using Kullback–Leibler divergence based on CGC genes and non-CGC genes. We detect cancer driver genes in two different ways. One is to detect driver genes from a single feature type, while the other is from the top N features. The first analysis denotes that the mutational features are the best characteristics. The second analysis reveals that the top 45 features are the most effective feature combinations and superior to the mutational features. The top 45 features not only contain mutational features but also three other types of features. Therefore, our study extends the detection of cancer driver genes and provides a more comprehensive understanding of cancer mechanisms.

SOX9: Advances in Gynecological Malignancies

Transcription factors of the SOX family were first discovered in mammals in 1990. The sex-determining region Y box 9 belongs to the SOX transcription factor family. It plays an important role in inducing tissue and cell morphogenesis, survival, and many developmental processes. Furthermore, it has been shown to be an oncogene in many tumors. Gynecological malignancies are tumors that occur in the female reproductive system and seriously threaten the lives of patients. Common gynecological malignancies include ovarian cancer, cervical cancer, and endometrial cancer. So far, the molecular mechanisms related to the incidence and development of gynecological malignancies remain unclear. This makes it particularly important to discover their common causative molecule and thus provide an effective therapeutic target. In recent years, studies have found that multiple mechanisms are involved in regulating the expression of the sex-determining region Y box 9, leading to the occurrence and development of gynecological malignancies. In this review, we discuss the prognostic value of SOX9 expression and the potential of targeting SOX9 for gynecological malignancy treatment. We also discuss progress regarding the role of SOX9 in gynecological malignancy pathogenesis through its mediation of important mechanisms, including tumor initiation and proliferation, apoptosis, migration, invasion, chemoresistance, and stem cell maintenance.

Inhibition of GATA2 in prostate cancer by a clinically available small molecule

Castration-resistant prostate cancer (CRPC) remains highly lethal and in need of novel, actionable therapeutic targets. The pioneer factor GATA2 is a significant prostate cancer (PC) driver and is linked to poor prognosis. GATA2 directly promotes androgen receptor (AR) gene expression (both full-length and splice-variant) and facilitates AR binding to chromatin, recruitment of coregulators, and target gene transcription. Unfortunately, there is no clinically applicable GATA2 inhibitor available at the moment. Using a bioinformatics algorithm, we screened in silico 2650 clinically relevant drugs for a potential GATA2 inhibitor. Validation studies used cytotoxicity and proliferation assays, global gene expression analysis, RT-qPCR, reporter assay, reverse phase protein array analysis (RPPA), and immunoblotting. We examined target engagement via cellular thermal shift assay (CETSA), ChIP-qPCR, and GATA2 DNA-binding assay. We identified the vasodilator dilazep as a potential GATA2 inhibitor and confirmed on-target activity via CETSA. Dilazep exerted anticancer activity across a broad panel of GATA2-dependent PC cell lines in vitro and in a PDX model in vivo. Dilazep inhibited GATA2 recruitment to chromatin and suppressed the cell-cycle program, transcriptional programs driven by GATA2, AR, and c-MYC, and the expression of several oncogenic drivers, including AR, c-MYC, FOXM1, CENPF, EZH2, UBE2C, and RRM2, as well as of several mediators of metastasis, DNA damage repair, and stemness. In conclusion, we provide, via an extensive compendium of methodologies, proof-of-principle that a small molecule can inhibit GATA2 function and suppress its downstream AR, c-MYC, and other PC-driving effectors. We propose GATA2 as a therapeutic target in CRPC.

Subcellular localization of HMGB1 in human cholangiocarcinoma: correlation with tumor stage

Cholangiocarcinoma (CCA) is a malignant disease with a poor prognosis, and several studies have been conducted using different molecular markers as a tool for CCA diagnosis, including Clonorchis sinensis (CS)-CCA. We initially identified the expression profiles of the three markers of interest, HMGB1, SOX9, and YAP1, using GSE (GSE76297 and GSE32958) datasets. Upregulated levels of these three proteins were detected in CCA samples compared to those in normal samples. To clarify this issue, 24 human CCA tissues with paired adjacent normal tissues were evaluated using immunohistochemical staining. Of the three markers, the total cellular staining intensities were scanned, and subcellular localization was scored in the nuclear and cytoplasmic regions. The intensities of HMGB1, SOX9, and YAP1 were elevated in CCA tissues than the adjacent normal tissues. Individual scoring of subcellular localization revealed that the expression levels of HMGB1 (nucleus) and YAP1 (nucleus and cytoplasm) were significantly different from the pathologic M stage. Moreover, the translocation pattern was categorized using "site-index", and the results demonstrated that the overexpression of HMGB1 and SOX9 was mostly observed in both the nucleus and cytoplasm, whereas YAP1 was predominantly expressed in the cytoplasm of tumor cells. Interestingly, the site index of HMGB1 was moderately correlated with the tumor stage (r = 0.441, p = 0.031). These findings imply that the overexpression of subcellular HMGB1 could be associated with the metastatic status of patients with CS-CCA, which was shown to be effective for CS-CCA prognosis.

Exosome circCMTM3 promotes angiogenesis and tumorigenesis of hepatocellular carcinoma through miR-3619-5p/SOX9

AIM

As one of the most common and lethal carcinomas, hepatocellular carcinoma (HCC) is a global health concern and affects millions of people worldwide. Current treatments for HCC are very limited due to its unclear pathogenesis. Here, we aim to further investigate the role of circCMTM3/microRNA (miR)-3619-5p in HCC.

METHODS

Human blood samples were collected from HCC patients and healthy people. Quantitative reverse transcription-polymerase chain reaction and western blot analysis were undertaken to measure levels of circCMTM3, miR-3619-5p, SOX9, and exosome markers. The MTT, colony formation, and Transwell assays were used to examine the viability, migration, and invasion of human umbilical vein endothelial cells (HUVECs), respectively. Tube formation assay was used to assess angiogenesis. Dual luciferase assay was used to validate circCMTM3/miR-3619-5p and miR-3619-5p/SOX9 interactions. A nude mouse xenograft model was used to test the role of circCMTM3 in HCC in vivo.

RESULTS

Levels of circCMTM3 in exosomes from HCC patients and cells were elevated. Knockdown of circCMTM3 greatly decreased viability, migration, and invasion of HUVECs, as well as angiogenesis. CircCMTM3 acted as a miR-3619-5p sponge and miR-3619-5p inhibitor reversed the effects of si-circCMTM3 on angiogenesis. MiR-3619-5p directly targeted SOX9 and modulated angiogenesis through SOX9. Furthermore, knockdown of circCMTM3 suppressed angiogenesis and HCC tumor growth in vivo.

CONCLUSION

The exosome circCMTM3/miR-3619-5p/SOX9 axis from HCC cells promotes angiogenesis and thus contributes to HCC tumorigenesis.

Angioregulatory microRNAs in breast cancer: Molecular mechanistic basis and implications for therapeutic strategies

•

Cancer-associated angiogenesis is a fundamental process in tumor growth and metastasis.

•

Angioregulatory miRNA–target gene interaction is not only involved in sprouting vessels of breast tumors but also, trans-differentiation of breast cancer cells to endothelial cells in a process termed vasculogenic mimicry.

•

Successful targeting of tumor angiogenesis is still a missing link in the treatment of Breast cancer (BC) due to the low effectiveness of anti-angiogenic therapies in this cancer.

•

Response to anti-angiogenic therapeutics are controlled by a miRNAs, so the identification of interaction networks of miRNAs–targets can be applicable in determining anti-angiogeneic therapy and new biomarkers in BC.

•

Angioregulatory miRNAs in breast cancer cells and their microenvironment have therapeutic potential in cancer treatment.

Background

Cancer-associated angiogenesis is a fundamental process in tumor growth and metastasis. A variety of signaling regulators and pathways contribute to establish neovascularization, among them as small endogenous non-coding RNAs, microRNAs (miRNAs) play prominent dual regulatory function in breast cancer (BC) angiogenesis.

Aim of Review

This review aims at describing the current state-of-the-art in BC angiogenesis-mediated by angioregulatory miRNAs, and an overview of miRNAs dysregulation association with the anti-angiogenic response in addition to potential clinical application of miRNAs-based therapeutics.

Key Scientific Concepts of Review

Angioregulatory miRNA–target gene interaction is not only involved in sprouting vessels of breast tumors but also, trans-differentiation of BC cells to endothelial cells (ECs) in a process termed vasculogenic mimicry. Using canonical and non-canonical angiogenesis pathways, the tumor cell employs the oncogenic characteristics such as miRNAs dysregulation to increase survival, proliferation, oxygen and nutrient supply, and treatment resistance. Angioregulatory miRNAs in BC cells and their microenvironment have therapeutic potential in cancer treatment. Although, miRNAs dysregulation can serve as tumor biomarker nevertheless, due to the association of miRNAs dysregulation with anti-angiogenic resistant phenotype, clinical benefits of anti-angiogenic therapy might be challenging in BC. Hence, unveiling the molecular mechanism underlying angioregulatory miRNAs sparked a booming interest in finding new treatment strategies such as miRNA-based therapies in BC.

SOX9 in prostate cancer is upregulated by cancer-associated fibroblasts to promote tumor progression through HGF/c-Met-FRA1 signaling

Transcription factor SOX9 was a biomarker for prostate cancer (Pca) with poor prognosis. Nevertheless, the regulatory mechanism underlying SOX9 upregulation still remains unclear. Several cytokines have been reported to be involved in the regulation of SOX9, suggesting that cancer-associated fibroblasts (CAFs), one of the main sources of secreted factors in the tumor microenvironment (TME), may play a role in regulating SOX9 expression. Herein, an in vitro model of paracrine interaction between primary CAFs and Pca cells was applied to investigate the molecular mechanism of SOX9 upregulation during Pca progression. The regulatory axis was validated by in vivo experiments and The Cancer Genome Atlas data. Conditional medium of CAFs (CAF-CM) upregulated the expression of SOX9, which was mutually proved to be essential for CAF-induced tumor progression. Further analysis showed that hepatocyte growth factor (HGF) secreted by CAFs was responsible for SOX9 elevation in Pca cells, via the activation of c-Met signaling. Mechanistically, HGF/c-Met signaling specifically activated MEK1/2-ERK1/2 pathway, which induced phosphorylation and upregulation of FRA1, which then transcriptionally upregulated SOX9 by binding to the promoter of SOX9 gene. Moreover, we identified that HGF/c-Met-ERK1/2-FRA1-SOX9 axis was relatively conserved between human and mouse species by validating in mouse Pca cells. Our results reveal a novel insight into the molecular mechanism that SOX9 in Pca cells is promoted by CAFs through HGF/c-Met-ERK1/2-FRA1 axis. Furthermore, SOX9 may serve as an alternative marker for the activated HGF/c-Met signaling to enroll the optimal Pca patients for HGF/c-Met inhibition treatment, since it is much more stable and easier to detect.

EGR1 promotes stemness and predicts a poor outcome of uterine cervical cancer by inducing SOX9 expression

BACKGROUND

Early growth response-1 (EGR1) is a transcription factor involved in the progression of several cancer types. However, the expression and clinical significance of EGR1 in uterine cervical cancer (CC) have not been elucidated.

OBJECTIVE

To investigate the expression, clinical significance and prognostic value of EGR1 in CC.

METHODS

The expression of EGR1 was detected in 13 CCs and paired adjacent tissues with qRT-PCR and in 144 CC tissues with immunohistochemistry (IHC). The IHC scores were used to divide the patients into subsets with low and high EGR1 expression. The correlations between the EGR1 expression and clinicopathological factors were analyzed with the chi-square test, and the prognostic significance of EGR1 expression was evaluated with univariate and multivariate analyses. The functions of EGR1 in the proliferation, invasion and stemness of CC cells were investigated, and the molecular mechanism was assessed by in vitro experiments.

RESULTS

High expression of EGR1 was significantly associated with low survival rates of CC. EGR1 is an independent prognostic biomarker of CC, and its high expression predicted a poor outcome. EGR1 facilitated stemness and thus promoted proliferation and invasion of CC cells. SOX9 played an essential role in the EGR1-induced progression of CC cells.

CONCLUSIONS

EGR1 is an independent prognostic biomarker of CC. High EGR1 expression promoted proliferation, invasion and stemness by increasing SOX9 expression in CC cells. Our results suggested that the EGR1-SOX9 axis may be a potential drug target and that blocking the EGR1-SOX9 axis may be a possible approach to treating CC.

Extracellular ATP promotes breast cancer invasion and chemoresistance via SOX9 signaling

Our previous research demonstrated that extracellular adenosine 5'-triphosphate (ATP) could promote breast cancer cell invasion. However, the impact of extracellular ATP on chemoresistance and the mechanisms behind ATP pro-invasion and pro-chemoresistance remain unclear. Here we aimed to determine the molecules or signaling pathways involved. cDNA microarray was performed to identify the differentially expressed genes before and after ATP treatment. As a result, Sex-determining region Y-box 9 (SOX9) was up-regulated after ATP treatment in breast cancer cells. In vitro invasion and migration assays demonstrated that knocking down SOX9 attenuated ATP-driven invasive capability. Mass spectrometry and co-IP revealed that SOX9 interacted with Janus kinase 1 (JAK1). Afterward, IL-6-JAK1-STAT3 signaling was demonstrated to promote SOX9 expression and invasion following ATP treatment. Notably, ATP-IL-6-SOX9 signaling was shown to stimulate chemoresistance in breast cancer cells. ChIP assays identified some potential SOX9 target genes, among which carcinoembryonic antigen-related cell adhesion molecule 5/6 (CEACAM5/6) was demonstrated to mediate ATP pro-invasive function, while ATP-binding cassette subfamily B member 1 (ABCB1) and ATP-binding cassette subfamily G member 2 (ABCG2) mediated ATP-driven chemoresistance. In addition, SOX9-knockdown and apyrase (an ATP hydrolase)-treated MDA-MB-231 cells illustrated decreased tumor growth and enhanced drug sensitivity in nude mice. In vitro spheroid formation assays also proved the significance of ATP-SOX9 in mediating chemoresistance. Moreover, molecules involved in ATP-SOX9 signaling were up-regulated in human breast carcinoma specimens and were associated with poor prognosis. Altogether, SOX9 signaling is vital in ATP-driven invasion and chemoresistance, which may serve as a potential target for breast cancer therapies.

The MRTF-A/miR-155/SOX1 pathway mediates gastric cancer migration and invasion

Background

Gastric cancer (GC) is the leading cause of death worldwide and is closely related to metastasis. MRTF-A is one of the most well-characterized genetic markers in cancer. However, the mechanism whereby MRTF-A mediate gastric cancer (GC) tumorigenesis is not fully clear. Increasing evidence has confirmed that miRNA dysregulation is involved in MRTF-A-mediated tumorigenesis, supporting their potential as therapeutic targets for cancer. Although miR-155 has been reported as an upregulated miRNA, the interplay between miR-155 and MRTF-A-mediated gastric cancer progression remain largely elusive.

Methods

Real-time PCR was performed to determine miR-155 expression after transfected with MRTF-A encoding plasmids and siRNA. Potential target genes were identified by Western blot and luciferase reporter assay. Chip assay was proved that MRTF-A binds in the promoter region of miR-155. Transwell assay and Scratch-healing migration assay was used to investigate the role of MRTF-A and SOX1 in gastric cancer cell migration and invasion.

Results

MRTF-A can interact with the miR-155 promoter to promote histone acetylation and RNA polymerase II recruitment via the Wnt-β-catenin pathway. miR-155 promotes gastric cancer cell migration by suppressing SOX1 expressiom by targeting its 3′UTR in vitro and in vivo. MRTF-A inhibited the inhibitory effects of SOX1 on gastric cancer cell migration by promoting the express -ion of miR-155.

Conclusion

Our data therefore provide important and novel insights into how the MRTF-A/miR-155/SOX1 pathway mediates migration and invasion in GC.

Dynamics of Cellular Plasticity in Prostate Cancer Progression

Despite the current advances in the treatment for prostate cancer, the patients often develop resistance to the conventional therapeutic interventions. Therapy-induced drug resistance and tumor progression have been associated with cellular plasticity acquired due to reprogramming at the molecular and phenotypic levels. The plasticity of the tumor cells is mainly governed by two factors: cell-intrinsic and cell-extrinsic. The cell-intrinsic factors involve alteration in the genetic or epigenetic regulators, while cell-extrinsic factors include microenvironmental cues and drug-induced selective pressure. Epithelial-mesenchymal transition (EMT) and stemness are two important hallmarks that dictate cellular plasticity in multiple cancer types including prostate. Emerging evidence has also pinpointed the role of tumor cell plasticity in driving anti-androgen induced neuroendocrine prostate cancer (NEPC), a lethal and therapy-resistant subtype. In this review, we discuss the role of cellular plasticity manifested due to genetic, epigenetic alterations and cues from the tumor microenvironment, and their role in driving therapy resistant prostate cancer.

SOX9 interacts with FOXC1 to activate MYC and regulate CDK7 inhibitor sensitivity in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is particularly sensitive to cyclin-dependent kinase 7 inhibitor, THZ1, compared to hormone receptor (HR)+ breast cancer, but our data found that different TNBC cell lines had a wide range of IC₅₀ values of THZ1, suggesting a possible heterogeneity in sensitivity to THZ1 in TNBC. To seek potential biomarkers of THZ1 sensitivity, we re-analyzed the mRNAs profile in breast cancer cells treated with THZ1 from the previous study and demonstrated that elevated expression of SOX9 was significantly associated with the sensitivity of THZ1 in TNBC. We also verified that SOX9 expression promoted cell proliferation, migration, stemness, and predicted poor prognosis. Moreover, based on the tissue array of 278 patients and over 900 samples from TCGA data, we found that SOX9 expression was significantly higher in TNBC than HR+ breast cancers. Furthermore, ChIP-sequencing indicated that SOX9 binding to enhancer near transcription factor FOXC1, was remarkably inhibited by THZ1. And we also demonstrated that SOX9 and FOXC1 interacted with each other, which might co-operate and co-regulate the MYC signaling pathway in TNBC. Mechanistically, SOX9 may sensitize TNBC cells to THZ1, in a FOXC1-related manner, suggesting that SOX9 could be as a predictive factor of THZ1.

Long noncoding RNA LINC00339 promotes the oncogenicity of gastric cancer by regulating SRY-box 9 expression via sponging of microRNA-539

Differential expression of LINC00339 is involved in the malignancy of multiple human cancer types. Nonetheless, the expression profile, functions, and potential mechanisms of action of LINC00339 in gastric cancer are yet to be fully elucidated. This study aimed at measuring LINC00339 expression in gastric cancer and examining the prognostic significance of LINC00339 in patients with gastric cancer. The detailed functions of LINC00339 with regard to the aggressive characteristics of gastric cancer cells and the underlying molecular mechanisms were investigated. Here, we found that LINC00339 expression was aberrantly high in gastric cancer and significantly associated with lymph node metastasis, invasive depth, and TNM stage. Patients with gastric cancer in a LINC00339 high-expression group showed shorter overall survival than patients in a LINC00339 low-expression group. A knockdown of LINC00339 suppressed gastric cancer cell proliferation, migration, and invasion and induced apoptosis in vitro and slowed tumor growth in vivo. In terms of the mechanism, LINC00339 was found to act as a molecular sponge on microRNA-539 (miR-539). SRY-box 9 (SOX9) was confirmed as a direct target gene of miR-539 in gastric cancer cells. An miR-539 knockdown attenuated the effects of the LINC00339 knockdown on the malignant characteristics of gastric cancer cells. Overall, LINC00339 plays a critical role in the malignancy of gastric cancer by regulating SOX9 via sponging of miR‑539. Our findings highlight the importance of the LINC00339-miR-539-SOX9 pathway in gastric cancer pathogenesis and may point to novel targets for the diagnosis, prognosis, and/or treatment of gastric cancer.

Long Non-Coding RNA LEF1-AS1 Promotes Migration, Invasion and Metastasis of Colon Cancer Cells Through miR-30-5p/SOX9 Axis

INTRODUCTION

Aberrant expression of long non-coding RNAs (lncRNAs) has been implicated in the tumorigenesis and progression of colon cancer. Lymphoid enhancer-binding factor 1 antisense RNA 1 (LEF1-AS1), a highly conserved and newly discovered long non-coding RNA, has been reported to be upregulated and correlated with poor prognosis in colon cancer, but the exact role of it remains uncertain.

MATERIALS AND METHODS

In our study, the biological functions of LEF1-AS1 in colon cancer were analyzed by cell viability assay, colony formation assay, scratch wound healing assay, transwell cell invasion assay, soft agar assay, luciferase reporter assay, pull down assay, tumor xenograft model and Western blot.

RESULTS

We found that LEF1-AS1 was upregulated in colon cancer patients and correlated with poor overall survival and recurrent-free survival. Besides, enforced expression of LEF1-AS1 in HT29 and T84 cells promoted migration, invasion, anchorage-independent growth, tumor xenograft formation and lung metastasis, while knockdown of LEF1-AS1 in COLO320 cells suppressed cell migration, invasion, anchorage-independent growth and tumor xenograft formation. In addition, LEF1-AS1 was directly interacted and inversely correlated with miR-30-5p in colon cancer, and SOX9 was a downstream target for miR-30-5p. LEF1-AS1 overexpression increased the expression level of SOX9, and restoration of SOX9 attenuated the effects caused by LEF1-AS1 knockdown in cell migration, invasion, anchorage-independent growth and tumor xenograft formation.

CONCLUSION

Our results indicated that LEF1-AS1 promoted migration, invasion and metastasis of colon cancer cells partially through miR-30-5p/SOX9 axis. The oncogenic LEF1-AS1 could be a potential prognostic biomarker for colon cancer.

SOX9: The master regulator of cell fate in breast cancer

SRY-related high-mobility group box 9 (SOX9) is an indispensable transcription factor that regulates multiple developmental pathways related to stemness, differentiation, and progenitor development. Previous studies have demonstrated that the SOX9 protein directs pathways involved in tumor initiation, proliferation, migration, chemoresistance, and stem cell maintenance, thereby regulating tumorigenesis as an oncogene. SOX9 overexpression is a frequent event in breast cancer (BC) subtypes. Of note, the molecular mechanisms and functional regulation underlying SOX9 upregulation during BC progression are still being uncovered. The focus of this review is to appraise recent advances regarding the involvement of SOX9 in BC pathogenesis. First, we provide a general overview of SOX9 structure and function, as well as its involvement in various kinds of cancer. Next, we discuss pathways of SOX9 regulation, particularly its miRNA-mediated regulation, in BC. Finally, we describe the involvement of SOX9 in BC pathogenesis via its regulation of pathways involved in regulating cancer hallmarks, as well as its clinical and therapeutic importance. In general, this review article aims to serve as an ample source of knowledge on the involvement of SOX9 in BC progression. Targeting SOX9 activity may improve therapeutic strategies to treat BC, but precisely inhibiting SOX9 using drugs and/or small peptides remains a huge challenge for forthcoming cancer research.

DDP-resistant ovarian cancer cells-derived exosomal microRNA-30a-5p reduces the resistance of ovarian cancer cells to DDP

Exosomes carrying microRNAs (miRNAs) have been demonstrated to play critical roles in the regulation of development, growth and metastasis of cancer. Bioinformatic predictions identified differentially expressed SRY-box 9 (SOX9) in OC, and the regulatory miRNA miR-139-5p. Here, we aim to evaluate the function of exosomal miR-139-5p in the sensitivity of ovarian cancer (OC) cells to cis-diamminedichloroplatinum(II) (DDP). Expression pattern of miR-139-5p and SOX9 in ovarian cancer cells (SKOV3) and DDP-resistant cells (SKOV3/DDP) was identified using reverse transcription quantitative polymerase chain reaction and western blot analysis. The relationship between miR-139-5p and SOX9 was validated using a dual-luciferase reporter assay. SKOV3/DDP cell line was developed and introduced with miR-30a-5p mimic to analyse the effects of miR-30a-5p on resistance to DDP. The in vitro and in vivo effects of exosomal miR-30a-5p on resistance of SKOV3 cells to DDP were assessed in a co-culture system of exosomes and OC cells as well as in tumour-bearing nude mice. High expression of SOX9 and low expression of miR-30-5p were witnessed in OC. Furthermore, miR-30-5p, a downregulated miRNA in SKOV3/DDP cells, increased the rate of cell apoptosis and enhanced the sensitivity of SKOV3/DDP cells to DDP by targeting SOX9. Moreover, exosomes carrying miR-30a-5p were identified to sensitize SKOV3/DDP cells to DDP both in vitro and in vivo. These data together supported an important conclusion that DDP-resistant OC cell-derived exosomal miR-30a-5p enhanced cellular sensitivity to DDP, highlighting a potential strategy to overcome drug resistance.

IL-1-conferred gene expression pattern in ERα+ BCa and AR+ PCa cells is intrinsic to ERα- BCa and AR- PCa cells and promotes cell survival

Background

Breast (BCa) and prostate (PCa) cancers are hormone receptor (HR)-driven cancers. Thus, BCa and PCa patients are given therapies that reduce hormone levels or directly block HR activity; but most patients eventually develop treatment resistance. We have previously reported that interleukin-1 (IL-1) inflammatory cytokine downregulates ERα and AR mRNA in HR-positive (HR⁺) BCa and PCa cell lines, yet the cells can remain viable. Additionally, we identified pro-survival proteins and processes upregulated by IL-1 in HR⁺ BCa and PCa cells, that are basally high in HR⁻ BCa and PCa cells. Therefore, we hypothesize that IL-1 confers a conserved gene expression pattern in HR⁺ BCa and PCa cells that mimics conserved basal gene expression patterns in HR⁻ BCa and PCa cells to promote HR-independent survival and tumorigenicity.

Methods

We performed RNA sequencing (RNA-seq) for HR⁺ BCa and PCa cell lines exposed to IL-1 and for untreated HR⁻ BCa and PCa cell lines. We confirmed expression patterns of select genes by RT-qPCR and used siRNA and/or drug inhibition to silence select genes in the BCa and PCa cell lines. Finally, we performed Ingenuity Pathway Analysis (IPA) and used the gene ontology web-based tool, GOrilla, to identify signaling pathways encoded by our RNA-seq data set.

Results

We identified 350 genes in common between BCa and PCa cells that are induced or repressed by IL-1 in HR⁺ cells that are, respectively, basally high or low in HR⁻ cells. Among these genes, we identified Sequestome-1 (SQSTM1/p62) and SRY (Sex-Determining Region Y)-Box 9 (SOX9) to be essential for survival of HR⁻ BCa and PCa cell lines. Analysis of publicly available data indicates that p62 and SOX9 expression are elevated in HR-independent BCa and PCa sublines generated in vitro, suggesting that p62 and SOX9 have a role in acquired hormone receptor independence and treatment resistance. We also assessed HR⁻ cell line viability in response to the p62-targeting drug, verteporfin, and found that verteporfin is cytotoxic for HR⁻ cell lines.

Conclusions

Our 350 gene set can be used to identify novel therapeutic targets and/or biomarkers conserved among acquired (e.g. due to inflammation) or intrinsic HR-independent BCa and PCa.

Cistrome Partitioning Reveals Convergence of Somatic Mutations and Risk Variants on Master Transcription Regulators in Primary Prostate Tumors

Thousands of noncoding somatic single-nucleotide variants (SNVs) of unknown function are reported in tumors. Partitioning the genome according to cistromes reveals the enrichment of somatic SNVs in prostate tumors as opposed to adjacent normal tissue cistromes of master transcription regulators, including AR, FOXA1, and HOXB13. This parallels enrichment of prostate cancer genetic predispositions over these transcription regulators' tumor cistromes, exemplified at the 8q24 locus harboring both risk variants and somatic SNVs in cis-regulatory elements upregulating MYC expression. However, Massively Parallel Reporter Assays reveal that few SNVs can alter the transactivation potential of individual cis-regulatory elements. Instead, similar to inherited risk variants, SNVs accumulate in cistromes of master transcription regulators required for prostate cancer development.

Sox9 in mouse urogenital sinus epithelium mediates elongation of prostatic buds and expression of genes involved in epithelial cell migration

Previous studies identified Sox9 as a critical mediator of prostate development but the precise stage when Sox9 acts had not been determined. A genetic approach was used to delete Sox9 from mouse urogenital sinus epithelium (UGE) prior to prostate specification. All prostatic bud types (anterior, dorsolateral and ventral) were stunted in Sox9 conditional knockouts (cKOs) even though the number of prostatic buds did not differ from that of controls. We concluded that Sox9 is required for prostatic bud elongation and compared control male, control female, Sox9 cKO male and Sox9 cKO female UGE transcriptomes to identify potential molecular mediators. We identified 702 sex-dependent and 95 Sox9-dependent genes. Thirty-one genes were expressed in both a sex- and Sox9-dependent pattern. A comparison of Sox9 cKO female vs control female UGE transcriptomes revealed 74 Sox9-dependent genes, some of which also function in cell migration. SOX9 regulates, directly or indirectly, a largely different profile of genes in male and female UGE. Eighty-three percent of Sox9-dependent genes in male UGE were not Sox9-dependent in female UGE. Only 16 genes were Sox9-dependent in the UGE of both sexes and seven had cell migration functions. These results support the notion that Sox9 promotes cell migration activities needed for prostate ductal elongation.

Induction of ALP and MMP9 activity facilitates invasive behavior in heterogeneous human BMSC and HNSCC 3D spheroids

Mesenchymal stem cells (MSCs) are multipotent progenitor cells capable of differentiating into adipocytic, osteogenic, chondrogenic, and myogenic lineages. There is growing evidence that MSCs home into the tumor microenvironment attracted by a variety of signals such as chemokines, growth factors, and cytokines. Tumor-homing stem cells may originate from bone marrow-derived MSCs (BMSCs) or adipose tissue-derived MSCs. Recent scientific data suggest that MSCs in combination with tumor cells can either promote or inhibit tumorigenic behavior. In head and neck squamous cell carcinoma (HNSCC), BMSCs are reported to be enriched with a potential negative role. Here, we evaluated the effect of BMSCs from 4 different donors in combination with 4 HNSCC cell lines in a 3-dimensional multicellular spheroid model. Heterogeneous combinations revealed an up-regulation of gene and protein expression of osteogenic markers runt-related transcription factor 2 (RUNX2) and alkaline phosphatase (ALP) together with a substantial secretion of matrix metalloproteinase 9. Moreover, heterogenous BMSC/tumor spheroids showed increased invasion compared with homogenous spheroids in a Boyden chamber invasion assay. Furthermore, inhibition of ALP resulted in a substantially decreased spreading of heterogeneous spheroids on laminin-rich matrix. In summary, our data suggest a prometastatic effect of BMSCs combined with HNSCC.-Wessely, A., Waltera, A., Reichert, T. E., Stöckl, S., Grässel, S., Bauer, R. J. Induction of ALP and MMP9 activity facilitates invasive behavior in heterogeneous human BMSC and HNSCC 3D-spheroids.

SOX9 drives the epithelial-mesenchymal transition in non-small-cell lung cancer through the Wnt/β-catenin pathway

Background

The distant metastasis of cancer cells is a risk factor for tumor lethality and poor prognosis in non-small-cell lung carcinoma (NSCLC). Increased SOX9 expression has been associated with clinical stage and poor prognosis in NSCLC, but the molecular mechanisms by which SOX9 promotes metastasis in NSCLC are still unknown.

Methods

The relationship between SOX9 expression and T, N, M classification was assessed using the χ² test and Spearman’s analysis in 142 immunohistochemically diagnosed specimens of NSCLC. We also generated SOX9-overexpression and SOX9-knockdown cells lines and their corresponding control cell lines by transfection with lentiviral constructs. In vivo assay, SOX9-overexpressing and SOX9-knockdown NSCLC cells were injected in zebrafish to examine distance metastasis. Gene set enrichment analysis (GSEA) was applied to analysis the correlation between SOX9 overexpression and Wnt/β-catenin pathway. Luciferase assay was used to check transcriptional activity of TCF/LEF and western blot and immunofluorescence was employed to detect β-catenin translocation in SOX9-overexpression, SOX9-knockdown and their corresponding control cell lines.

Results

We found that SOX9 overexpression correlates with the T, N and M stage significantly (p = 0.03, 0.000, and 0.032 respectively) in 142 immunohistochemically diagnosed specimens of NSCLC. SOX9 overexpression was found to decrease the expression of the epithelial cell markers E-cadherin and γ-catenin and increase the expression of the mesenchymal cell markers N-cadherin and vimentin. An in vivo assay showed distant metastasis of the SOX9-overexpressing cells, which was not observed in the SOX9-knockdown cells. These findings indicate that SOX9 promotes distant metastasis by promoting EMT in NSCLC cells. GSEA showed that SOX9 overexpression was significantly correlated with the Wnt/β-catenin pathway which was corroborated by the expression of EMT-associated proteins in this pathway and its downstream target genes. SOX9 overexpression was also found to enhance the transcriptional activity of TCF/LEF, promote the nuclear translocation of β-catenin and increase the phosphorylation of GSK3β at Ser9. Further, inhibition of β-catenin suppressed the metastasis-promoting effects of SOX9 overexpression.

Conclusions

This study is the first to report that SOX9 is associated with clinical TNM stage and indicates that SOX9 promotes migration, invasion and the EMT process through the Wnt/β-catenin pathway.

Interplay Between SOX9, Wnt/β-Catenin and Androgen Receptor Signaling in Castration-Resistant Prostate Cancer

Androgen receptor (AR) signaling plays a key role not only in the initiation of prostate cancer (PCa) but also in its transition to aggressive and invasive castration-resistant prostate cancer (CRPC). However, the crosstalk of AR with other signaling pathways contributes significantly to the emergence and growth of CRPC. Wnt/β-catenin signaling facilitates ductal morphogenesis in fetal prostate and its anomalous expression has been linked with PCa. β-catenin has also been reported to form complex with AR and thus augment AR signaling in PCa. The transcription factor SOX9 has been shown to be the driving force of aggressive and invasive PCa cells and regulate AR expression in PCa cells. Furthermore, SOX9 has also been shown to propel PCa by the reactivation of Wnt/β-catenin signaling. In this review, we discuss the critical role of SOX9/AR/Wnt/β-catenin signaling axis in the development and progression of CRPC. The phytochemicals like sulforaphane and curcumin that can concurrently target SOX9, AR and Wnt/β-catenin signaling pathways in PCa may thus be beneficial in the chemoprevention of PCa.

SOX9 Stem-Cell Factor: Clinical and Functional Relevance in Cancer

Transcriptional and epigenetic embryonic programs can be reactivated in cancer cells. As result, a specific subset of undifferentiated cells with stem-cells properties emerges and drives tumorigenesis. Recent findings have shown that ectoderm- and endoderm-derived tissues continue expressing stem-cells related transcription factors of the SOX-family of proteins such as SOX2 and SOX9 which have been implicated in the presence of cancer stem-like cells (CSCs) in tumors. Currently, there is enough evidence suggesting an oncogenic role for SOX9 in different types of human cancers. This review provides a summary of the current knowledge about the involvement of SOX9 in development and progression of cancer. Understanding the functional roles of SOX9 and clinical relevance is crucial for developing novel treatments targeting CSCs in cancer.

[Effect of down-regulation of sex determining region Y-box 9 on epithelial mesenchymal transition and cloning of oral squamous carcinoma cells]

OBJECTIVE

To investigate the effect of sex determining region Y-box 9 (SOX9) on epithelial mesenchymal transition (EMT) and cloning of oral squamous cell carcinoma (OSCC).

METHODS

siRNA control, SOX9 siRNA were transfected into BcaCD885 cells in OSCC. Simultaneously, cells that did not undergo transfection were used as the control. Quantitative real time polymerase chain reaction (qRT-PCR) and Western blot were used to select SOX9 siRNA1 with enhanced interference effect. A cell cloning assay was used to determine the cell's clone formation ability. E-cadherin and Vimentin expressions were detected by immunofluorescence. The expressions of E-cadherin, matrix metalloprotease 2 (MMP-2), Vimentin and matrix metalloprotease 9 (MMP-9) were detected by Western blot. Cell invasion and migration were detected in the Transwell compartment.

RESULTS

The levels of SOX9 mRNA and protein in SOX9 siRNA cells were significantly lower than those of the control (P<0.05). An increase in the number of SOX9 siRNA1 cell clonesled to the considerable decrease of the number of cell invasion and migration. In addition, levels of MMP-2 and MMP-9 proteins in cells decreased significantly compared with the control (P<0.05). The level of Vimentin expression in SOX9 siRNA1 cells decreased, and expression level of E-cadherin was elevated. Cell EMT was inhibited compared with the control, and the difference was statistically significant (P<0.05).

CONCLUSIONS

Down-regulation of SOX9 inhibited EMT, clonogenic formation, cell invasion and OSCC migration.

Increased SOX9 Expression in Premalignant and Malignant Pancreatic Neoplasms

BACKGROUND

SOX9, a progenitor cell marker, is important for pancreatic ductal development. Our goal was to examine SOX9 expression differences in intraductal papillary mucinous neoplasms (IPMNs) and ductal adenocarcinoma (PDAC) compared with benign pancreatic duct (BP).

METHODS

SOX9 expression was evaluated by immunohistochemistry performed on 93 specimens: 37 BP, 24 low grade (LG) IPMN, 12 high grade (HG) IPMN, and 20 PDAC. A linear mixed-effects model was used to compare the percentage of cells expressing SOX9 by specimen type. A separate linear mixed-effects model evaluated differences in SOX9 expression by staining intensity in pancreatic epithelial cells.

RESULTS

Nuclear SOX9 expression was detected in the epithelial cells of 98% HG IPMN, 93% LG IPMN, 83% PDAC, and 60% BP. Compared with BP, SOX9 was expressed from a significantly greater percentage of cells in LG IMPN, HG IMPN, and PDAC (p < 0.001 for each). BP and PDAC showed greater variability in SOX9 expression in epithelial cells compared with IPMNs which showed strong, homogenous SOX9 expression in almost all cells. Compared with BP, both LG and HG IPMN showed significantly greater SOX9 expression (p < 0.001 for each), but there was no significant difference in SOX9 expression between LG and HG IPMN (p > 0.05). PDAC had significantly higher expression of SOX9 compared with BP but significantly lower SOX9 expression compared with LG or HG IPMN (p < 0.001 for each).

CONCLUSIONS

IPMNs demonstrated the highest expression levels of SOX9. SOX9 expression in BP and PDAC demonstrated much more heterogeneity compared with the strong, uniform expression in IPMN.

Construction of an miRNA‑gene regulatory network in colorectal cancer through integrated analysis of mRNA and miRNA microarrays

The aim of the present study was to identify potential biomarkers associated with colorectal cancer (CRC). The GSE32323 and GSE53592 mRNA and microRNA (miRNA) expression profiles were selected from the Gene Expression Omnibus database. The differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) in CRC tissue samples compared with surrounding control tissue samples (DEGs‑CC), and DEGs in cells treated with 5‑aza‑2'‑deoxycitidine compared with untreated cells (DEGs‑TC) were identified with the Limma package. The Database for Annotation, Visualization and Integrated Discovery was used to conduct the functional and pathways enrichment analysis. Differential co‑regulation networks were constructed using the DCGL package of R. The targets of DEMs were identified using TargetScan. The overlaps between DEGs and the targets were selected. The miRNA‑gene regulatory network of the overlaps was established. There were 145 DEMs, and 1,284 DEGs in DEGs‑CC, and 101 DEGs in DEGs‑TC. DEGs‑CC were enriched in 196 Gene Ontology (GO) terms and 23 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. DEGs‑TC were enriched in 46 GO terms and two KEGG pathways. A differential co‑regulation network of the DEGs and a miRNA‑gene regulatory network between DEMs and overlapped DEGs were respectively constructed. miR‑124‑3p, miR‑145‑5p and miR‑320a may be critical in CRC, and serum/glucocorticoid regulated kinase 1 and SRY‑box 9 may be potential biomarkers for CRC tumor progression.

MicroRNA-511 inhibits malignant behaviors of breast cancer by directly targeting SOX9 and regulating the PI3K/Akt pathway

Numerous studies have revealed that a subset of microRNAs (miRNAs) is aberrantly expressed in breast cancer. The dysregulation of miRNAs is involved in the tumorigenesis and progression of breast cancer due to their negative regulation of downstream target genes. Therefore, the identification of deregulated miRNAs in breast cancer may provide important insights into the diagnosis and treatment of patients with this disease. miRNA‑511 (miR‑511) has been identified to be deregulated in diverse human cancer types; however, neither the expression status nor the detailed roles of miR‑511 in breast cancer have been clarified. Thus, it was aimed to determine the expression of miR‑511 in breast cancer, examine the role in malignant progression and explore its downstream targets. The results of the present study revealed that the expression of miR‑511 was downregulated in breast cancer tissues and cell lines. Decreased expression of miR‑511 was significantly associated with lymph node metastasis and tumor stage in patients with breast cancer. Functional analyses revealed that restoring miR‑511 expression suppressed breast cancer cell proliferation and colony formation, promoted apoptosis and reduced metastasis in vitro, while it attenuated tumor growth in vivo. Additionally, it was revealed that SRY‑box 9 (SOX9) was a direct target gene of miR‑511 in breast cancer cells. SOX9 was upregulated in breast cancer tissues and its expression was inversely correlated with that of miR‑511. Furthermore, SOX9 inhibition simulated the tumor‑suppressive roles of miR‑511 overexpression in breast cancer cells, while SOX9 reintroduction partially rescued these effects of miR‑511. Notably, the upregulation of miR‑511 targeted SOX9 to deactivate the PI3K/Akt signaling in breast cancer in vitro and in vivo. In conclusion, miR‑511 was downregulated in breast cancer, and impeded its malignant progression by directly targeting SOX9 and regulating the PI3K/Akt pathway. Thus, miR‑511 is a potential therapeutic target in breast cancer.

TGF-β1-SOX9 axis-inducible COL10A1 promotes invasion and metastasis in gastric cancer via epithelial-to-mesenchymal transition

Molecular biomarkers that predict disease progression might promote drug development and therapeutic strategies in aggressive cancers, such as gastric cancer (GC). High-throughput mRNA sequencing (RNA-seq) revealed that collagen type X alpha 1 (COL10A1) is a disease progression-associated gene. Analysis of 103 GC patients showed that high COL10A1 mRNA expression was associated with GC metastasis and reduced survival. We analyzed the COL10A1 promoter using the UCSC genome website and JASPAR database, and we found potential SOX9 binding site. Here, we demonstrated that SOX9 and COL10A1 were both up-regulated in GC. We observed a positive correlation between the expression patterns of SOX9 and COL10A1 in GC cells and tissues. The results of electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP) assay and promoter reporter indicated that SOX9 could directly bind to the COL10A1 gene promoter and activate its transcription. Biological function experiments showed that COL10A1 regulated the migration and invasion of GC cells. Knockdown COL10A1 inhibited lung and abdominal cavity metastasis in a nude mouse model. Moreover, transforming growth factor-β1 (TGF-β1) treatment up-regulated the phosphorylation of Smad2 and increased SOX9 and COL10A1 expression. COL10A1 was confirmed to be a potential inducer of epithelial-to-mesenchymal transition (EMT). SOX9 was essential for COL10A1-mediated EMT, and cell migration, invasion and metastasis. Co-expression of SOX9 and COL10A1 was associated with tumor progression and was strongly predictive of overall survival in GC patients. In summary, this study elucidated the mechanistic link between COL10A1 and the TGF-β1-SOX9 axis. These findings indicated that COL10A1 might play a crucial role in GC progression and serve as a potential biomarker and therapeutic target in GC patients.

Prostate Organogenesis

The prostate is a male exocrine gland that secretes components of the seminal fluid. In men, prostate tumors are one of the most prevalent cancers. Studies on the development of the prostate have given a better understanding of the processes and genes that are important in the formation of this organ and have provided insights into the mechanisms of prostate tumorigenesis. These developmental studies have provided evidence that some of the genes and signaling pathways involved in development are reactivated or deregulated during prostate cancer. The prostate goes through a number of different stages during organogenesis, which include organ specification, epithelial budding, branching morphogenesis, canalization, and cytodifferentiation. During development, these processes are tightly regulated, many of which are controlled by the male hormone androgens. The majority of prostate tumors remain hormone regulated, and antiandrogen therapy is a first-line therapy, highlighting the important link between prostate organogenesis and cancer. In this review, we describe some of the data on genes that have important roles during prostate development that also have strong evidence linking them to prostate cancer.

Identification of an IL-1-induced gene expression pattern in AR+ PCa cells that mimics the molecular phenotype of AR- PCa cells

BACKGROUND

In immunosurveillance, bone-derived immune cells infiltrate the tumor and secrete inflammatory cytokines to destroy cancer cells. However, cancer cells have evolved mechanisms to usurp inflammatory cytokines to promote tumor progression. In particular, the inflammatory cytokine, interleukin-1 (IL-1), is elevated in prostate cancer (PCa) patient tissue and serum, and promotes PCa bone metastasis. IL-1 also represses androgen receptor (AR) accumulation and activity in PCa cells, yet the cells remain viable and tumorigenic; suggesting that IL-1 may also contribute to AR-targeted therapy resistance. Furthermore, IL-1 and AR protein levels negatively correlate in PCa tumor cells. Taken together, we hypothesize that IL-1 reprograms AR positive (AR⁺ ) PCa cells into AR negative (AR^- ) PCa cells that co-opt IL-1 signaling to ensure AR-independent survival and tumor progression in the inflammatory tumor microenvironment.

METHODS

LNCaP and PC3 PCa cells were treated with IL-1β or HS-5 bone marrow stromal cell (BMSC) conditioned medium and analyzed by RNA sequencing and RT-QPCR. To verify genes identified by RNA sequencing, LNCaP, MDA-PCa-2b, PC3, and DU145 PCa cell lines were treated with the IL-1 family members, IL-1α or IL-1β, or exposed to HS-5 BMSC in the presence or absence of Interleukin-1 Receptor Antagonist (IL-1RA). Treated cells were analyzed by western blot and/or RT-QPCR.

RESULTS

Comparative analysis of sequencing data from the AR⁺ LNCaP PCa cell line versus the AR^- PC3 PCa cell line reveals an IL-1-conferred gene suite in LNCaP cells that is constitutive in PC3 cells. Bioinformatics analysis of the IL-1 regulated gene suite revealed that inflammatory and immune response pathways are primarily elicited; likely facilitating PCa cell survival and tumorigenicity in an inflammatory tumor microenvironment.

CONCLUSIONS

Our data supports that IL-1 reprograms AR⁺ PCa cells to mimic AR^- PCa gene expression patterns that favor AR-targeted treatment resistance and cell survival.

MicroRNA-216b regulated proliferation and invasion of non-small cell lung cancer by targeting SOX9

Micro (mi)RNAs are small, evolutionarily conserved and endogenous noncoding RNA molecules between 19 and 24 nucleotides in length. The potential roles of miRNAs in the carcinogenesis and progression of non-small cell lung cancer (NSCLC) have been studied previously. In the present study, it was revealed that miRNA-216b (miR-216b) expression was lower in NSCLC tissue and cell lines compared with that in adjacent healthy lung tissue samples and the normal bronchial epithelial 16HBE cell line, respectively. The ectopic expression of miR-216b inhibited the proliferation and invasion of NSCLC cells in vitro. SRY-Box 9 (SOX9) was identified as a direct target of miR-216b in NSCLC. In addition, SOX9 small interfering RNA was able to mimic the effects of miR-216b overexpression on cell proliferation and invasion in NSCLC. Therefore, the data reported in the present study demonstrate that miR-216b is an important tumor suppressor in NSCLC. These data may contribute to the understanding of the molecular mechanism underlying the carcinogenesis and progression of NSCLC, and provide novel therapies for patients with NSCLC.

Discovery and characterization of small molecules targeting the DNA-binding ETS domain of ERG in prostate cancer

Genomic alterations involving translocations of the ETS-related gene ERG occur in approximately half of prostate cancer cases. These alterations result in aberrant, androgen-regulated production of ERG protein variants that directly contribute to disease development and progression. This study describes the discovery and characterization of a new class of small molecule ERG antagonists identified through rational in silico methods. These antagonists are designed to sterically block DNA binding by the ETS domain of ERG and thereby disrupt transcriptional activity. We confirmed the direct binding of a lead compound, VPC-18005, with the ERG-ETS domain using biophysical approaches. We then demonstrated VPC-18005 reduced migration and invasion rates of ERG expressing prostate cancer cells, and reduced metastasis in a zebrafish xenograft model. These results demonstrate proof-of-principal that small molecule targeting of the ERG-ETS domain can suppress transcriptional activity and reverse transformed characteristics of prostate cancers aberrantly expressing ERG. Clinical advancement of the developed small molecule inhibitors may provide new therapeutic agents for use as alternatives to, or in combination with, current therapies for men with ERG-expressing metastatic castration-resistant prostate cancer.

SOX9 is an atypical intestinal tumor suppressor controlling the oncogenic Wnt/ß-catenin signaling

SOX9 inactivation is frequent in colorectal cancer (CRC) due to SOX9 gene mutations and/or to ectopic expression of MiniSOX9, a dominant negative inhibitor of SOX9. In the present study, we report a heterozygous L142P inactivating mutation of SOX9 in the DLD-1 CRC cell line and we demonstrate that the conditional expression of a wild type SOX9 in this cell line inhibits cell growth, clonal capacity and colonosphere formation while decreasing both the activity of the oncogenic Wnt/ß-catenin signaling pathway and the expression of the c-myc oncogene. This activity does not require SOX9 transcriptional function but, rather, involves an interaction of SOX9 with nuclear ß-catenin. Furthermore, we report that SOX9 inhibits tumor development when conditionally expressed in CRC cells injected either subcutaneous or intraperitoneous in BALB/c mice as an abdominal metastasis model. These observations argue in favor of a tumor suppressor activity for SOX9. As an siRNA targeting SOX9 paradoxically also inhibits DLD-1 and HCT116 CRC cell growth, we conclude that there is a critical level of endogenous active SOX9 needed to maintain CRC cell growth.

In vitro study on the role of SOX9 in trastuzumab resistance of adenocarcinoma of the esophagogastric junction

Trastuzumab is recommended for the treatment of human epidermal growth factor receptor 2-positive adenocarcinoma of the esophagogastric junction (AEG) in combination with chemotherapy; however, drug resistance has severely affected its clinical application. The present study aimed to investigate the effect of sex determining region Y-box 9 (SOX9), a prognostic marker in adjuvant oncological settings, on AEG cell proliferation and apoptosis in the presence or absence of trastuzumab. Furthermore, the molecular mechanism underlying the role of SOX9 in trastuzumab resistance was explored. ESO26 cells were treated with various concentrations of trastuzumab, and trastuzumab induced SOX9 expression in a concentration-dependent manner, as determined by reverse transcription-quantitative polymerase chain reaction and western blotting analyses. Transfection of ESO26 cells with SOX9 small interfering RNA was conducted to knock down SOX9 expression, and the results of MTT and flow cytometry assays demonstrated that SOX9 knockdown sensitized ESO26 cells to trastuzumab by inhibiting cell proliferation and enhancing cell apoptosis. In addition, it was observed that the trastuzumab-induced phosphorylation of AKT was suppressed by SOX9 knockdown. In conclusion, the present study demonstrated that SOX9 participated in trastuzumab resistance by affecting cell proliferation and apoptosis, and indicated that SOX9 may exert its effect on trastuzumab resistance via activation of the phosphatidylinositol-3-kinase/AKT signaling pathway. This study identified a novel mechanism underlying trastuzumab resistance in vitro and may be useful in improving the efficacy of trastuzumab treatment.

Genome-Wide Methylation Patterns in Androgen-Independent Prostate Cancer Cells: A Comprehensive Analysis Combining MeDIP-Bisulfite, RNA, and microRNA Sequencing Data

This study aimed to investigate the mechanisms underlying the development of the androgen-independent phenotype in prostate cancer. Methylation patterns were detected in androgen-independent and androgen-dependent lymph node carcinoma of the prostate (LNCaP) prostate carcinoma cells based on methylated DNA immunoprecipitation-bisulfite sequencing data and differentially methylated regions (DMRs) were identified. Differentially expressed genes (DEGs) and micro RNAs (miRNAs) with DMRs (named MDEGs and MDEmiRNAs) were identified by combining transcriptome and methylation data, and transcription factor (TF)-DEGs with DMRs in promoter (PMDEGs) and MDEmiRNA-MDEGs networks were constructed. Furthermore, a time-course analysis of gene transcription during androgen deprivation was performed based on microarray data and DMRs, MDEGs, and DEmiRNAs were validated. In total, 18,447 DMRs, 3369 MDEGs, 850 PMDEGs, and 1 MDEmiRNA (miR-429) were identified. A TF-target network (94 PMDEGs and 5 TFs) and a miRNA–target network (172 MDEGs and miR-429) were constructed. Based on the time-course analysis of genes in the networks, NEDD4L and PBX3 were targeted by SOX5, while GNAQ, ANLN, and KIF11 were targeted by miR-429. The expression levels of these genes and miR-429 were confirmed by quantitative real-time polymerase chain reaction. Additionally, 109 DMRs were confirmed using additional public datasets. The regulatory pathways SOX5-NEDD4L/PBX3, miR429-GNAQ/ANLN—RHOA, and miR429-ANLN—KIF11 may participate in the progression of the androgen-independent phenotype in prostate cancer.

SOX9-PDK1 axis is essential for glioma stem cell self-renewal and temozolomide resistance

Glioblastoma multiforme (GBM) is the most common and aggressive brain tumor with limited therapeutic options. Glioma stem cell (GSC) is thought to be greatly responsible for glioma tumor progression and drug resistance. But the molecular mechanisms of GSC deriving recurrence and drug resistance are still unclear. SOX9 (sex-determining region Y (SRY)-box9 protein), a transcription factor expressed in most solid tumors, is reported as a key regulator involved in maintaining cancer hallmarks including the GSCs state. Previously, we have observed that silencing of SOX9 suppressed glioma cells proliferation both in vitro and in vivo. Here, we found that SOX9 was essential for GSC self-renewal. Silencing of SOX9 down-regulated a broad range of stem cell markers and inhibited glioma cell colony and sphere formation. We identified pyruvate dehydrogenase kinase 1 (PDK1) as a target gene of SOX9 using microarray analyses. PDK1 inactivation greatly inhibited glioma cell colony and sphere formation and sensitized glioma spheres to temozolomide (TMZ) toxicity. In addition, SOX9-shRNA and PDK1 inhibitor could greatly sensitize GSC to TMZ in vivo. Taken together, our data reveals that SOX9-PDK1 axis is a key regulator of GSC self-renewal and GSC temozolomide resistance. These findings may provide help for future human GBM therapy.

Upregulated SOX9 expression indicates worse prognosis in solid tumors: a systematic review and meta-analysis

It was recently reported that increased SOX9 expression drives tumor growth and promotes cancer invasion during human tumorigenicity and metastasis. However, the prognostic value of SOX9 for the survival of patients with solid tumors remains controversial. The present meta-analysis was thus performed to highlight the link between dysregulated SOX9 expression and prognosis in cancer patients. A systematic literature search was conducted using the electronic databases PubMed, Web of Science and Embase to identify eligible studies. A random-effects meta-analytical model was employed to correlate SOX9 expression with overall survival (OS), disease-free survival (DFS) and clinicopathological features. In total, 17 studies with 3307 patients were eligible for the final analysis. Combined hazard ratios (HRs) and 95% confidence intervals (CIs) suggested that high SOX9 expression has an unfavourable impact on OS (HR = 1.66, 95% CI 1.36-2.02, P < 0.001) and DFS (HR = 3.54, 95% CI 2.29-5.47, P = 0.008) in multivariate analysis. Additionally, the pooled odds ratios (ORs) indicated that SOX9 over-expression is associated with large tumor size, lymph node metastasis, distant metastasis and a higher clinical stage. Overall, these results indicated that SOX9 over-expression in patients with solid tumors might be related to poor prognosis and could serve as a potential predictive marker of poor clinicopathological prognosis factor.

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.

DNA hypermethylated status and gene expression of PAX1/SOX1 in patients with colorectal carcinoma

Background

Colorectal cancer (CRC) is a widespread and aggressive carcinoma with poor prognosis. Hypermethylation of specific gene promoters is an important mechanism of CRC. In this study, we investigated the hypermethylation of paired boxed gene 1 (PAX1) and sex-determining region Y-related high-mobility group box 1 (SOX1) genes in CRC tissues.

Methods

DNA methylation at cg2,09,07,471 PAX1 and cg0,66,75,478 SOX1 from 166 cancer tissues and 37 normal tissues from CRC patients were compared using datasets downloaded from The Cancer Genome Atlas. Quantitative methylation-specific polymerase chain reaction and assay of PAX1 and SOX1 were performed in dissected tumor and paracancerous tissues by surgery from 41 CRC patients. Quantitative reverse transcription polymerase chain reaction and immunohistochemistry assay were performed in both CRC and paired normal tissues to detect mRNA and protein expression, respectively.

Results

Methylation levels of PAX1/SOX1 genes were significantly higher in cancer tissues than in paired normal tissues. PAX1 and SOX1 genes were methylated in 28 (68.3%) of the 41 CRC samples but in 5 (12.2%) and 0 (0%) of the paired normal control samples (both P<0.001), respectively. Sensitivities and specificities of PAX1 methylation for the detection of cancer were 68.3% and 87.8%, respectively, whereas the corresponding values for SOX1 were 68.3% and 100%. However, the Kaplan–Meier analysis illustrated no significant difference in the overall survivals between patients with high and low methylation levels of SOX1 or PAX1 (P>0.5). In addition, the methylation level of PAX1/SOX1 was significantly higher in CRC patients with high TNM stage (TNM stage III/IV, 3.11±2.43) than those with low TNM stage (TNM stage I/II, 1.26±2.94, P<0.05). Relative RNA and protein expression levels of PAX1/SOX1 were both significantly lower in CRC tissues than in their paired normal tissue.

Conclusions

This study is the first analysis of the methylation of PAX1/SOX1, which may be new biomarkers for CRC screening.

Prostate organogenesis: tissue induction, hormonal regulation and cell type specification

Prostate organogenesis is a complex process that is primarily mediated by the presence of androgens and subsequent mesenchyme-epithelial interactions. The investigation of prostate development is partly driven by its potential relevance to prostate cancer, in particular the apparent re-awakening of key developmental programs that occur during tumorigenesis. However, our current knowledge of the mechanisms that drive prostate organogenesis is far from complete. Here, we provide a comprehensive overview of prostate development, focusing on recent findings regarding sexual dimorphism, bud induction, branching morphogenesis and cellular differentiation.

Expression and Therapeutic Potential of SOX9 in Chordoma

Purpose: Conventional chemotherapeutic agents are ineffective in the treatment of chordoma. We investigated the functional roles and therapeutic relevance of the sex-determining region Y (SRY)-box 9 (SOX9) in chordoma.Experimental Design: SOX9 expression was examined by immunohistochemistry (IHC) using 50 chordoma tissue samples. SOX9 expression in chordoma cell lines was examined by Western blot and immunofluorescent assays. We used synthetic human SOX9 siRNA to inhibit the expression of SOX9. Cell proliferation ability and cytotoxicity of inhibiting SOX9 were assessed by 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) and clonogenic assays. The effect of SOX9 knockdown on chordoma cell motility was evaluated by a wound-healing assay and a Transwell invasion chamber assay. Knockdown of SOX9 induced apoptosis, cell-cycle arrest, as well as decreased expression of cancer stem cell markers were determined by Western blot and flow cytometric assays. The effect of the combination of SOX9 siRNA and the chemotherapeutic drug doxorubicin/cisplatin on chordoma cells was assessed by an MTT assay.Results: Tissue microarray and IHC analysis showed that SOX9 is broadly expressed in chordomas and that higher expression levels of SOX9 correlated with a poor prognosis. RNA interference (RNAi)-mediated knockdown of SOX9 inhibited chordoma cell growth, decreased cell motility, and induced apoptosis as well as cell-cycle arrest. Moreover, the combination of SOX9 inhibition and chemotherapeutic drugs had an enhanced anti-cancer effect on chordoma cells.Conclusions: Our results demonstrate that SOX9 plays a crucial role in chordoma. Targeting SOX9 provides a new rationale for treatment of chordoma. Clin Cancer Res; 23(17); 5176-86. ©2017 AACR.