OTX1 Contributes to Hepatocellular Carcinoma Progression by Regulation of ERK/MAPK Pathway

Hypermethylation Loci of ZNF671, IRF8, and OTX1 as Potential Urine-Based Predictive Biomarkers for Bladder Cancer

Bladder cancer (BCa) is a significant health issue and poses a healthcare burden on patients, highlighting the importance of an effective detection method. Here, we developed a urine DNA methylation diagnostic panel for distinguishing between BCa and non-BCa. In the discovery stage, an analysis of the TCGA database was conducted to identify BCa-specific DNA hypermethylation markers. In the validation phase, DNA methylation levels of urine samples were measured with real-time quantitative methylation-specific PCR (qMSP). Comparative analysis of the methylation levels between BCa and non-BCa, along with the receiver operating characteristic (ROC) analyses with machine learning algorithms (logistic regression and decision tree methods) were conducted to develop practical diagnostic panels. The performance evaluation of the panel shows that the individual biomarkers of ZNF671, OTX1, and IRF8 achieved AUCs of 0.86, 0.82, and 0.81, respectively, while the combined yielded an AUC of 0.91. The diagnostic panel using the decision tree algorithm attained an accuracy, sensitivity, and specificity of 82.6%, 75.0%, and 90.9%, respectively. Our results show that the urine-based DNA methylation diagnostic panel provides a sensitive and specific method for detecting and stratifying BCa, showing promise as a standard test that could enhance the diagnosis and prognosis of BCa in clinical settings.

OTX1 regulates tumorigenesis and metastasis in glioma

The most prevalent kind of primary brain tumors, gliomas, have a dismal prognosis. Recent advances in the tumor-promoting ability of OTX1 have drawn increasing attention. The overexpression of OTX1 has been reported to be associated with tumor-promoting effects in several malignancies, but its expression in gliomas is unknown. The oncogene OTX1 is increased in gliomas and is linked to a poor prognosis, as we show here. The degree of OTX1 positive expression is doubtlessly concomitant with the grade of glioma. We observed that OTX1 was up-regulated in gliomas, influenced the epithelial-mesenchymal transition (EMT), encouraged glioma cell growth and proliferation, and was linked to a poor clinical outcome for patients. At present, the prognosis of glioma is still not optimistic, and further research is needed to find a new target for treatment. According to our research, OTX1 is anticipated to emerge as a novel biological target for determining glioma prognosis and treatment.

MicroRNA-195-5p Attenuates Pregnancy-Induced Hypertension by Inhibiting Oxidative Stress via OTX1/MAPK Signaling Pathway

Pregnancy-induced hypertension (PIH) is a hypertensive disorder during pregnancy and can induce perinatal death of human infants. MicroRNA (miR)-195-5p was validated to display low expression in severe preeclampsia placentas, but the role of miR-195-5p in pregnancy-induced hypertension (PIH) has not been investigated. The study emphasized on the functions and mechanism of miR-195-5p in PIH. A reduced uterine perfusion pressure (RUPP) rat model was established to mimic PIH in vivo. Adenovirus (Ad)-miR-195-5p agomir and/or Ad-OTX1 were further injected into some model rats. RT-qPCR was conducted to assess the expression of miR-195-5p and orthodenticle homeobox 1 (OTX1) in rat placental tissues, the isolated aortic endothelial cells (AECs), and in serum samples of PIH patients. Western blot analysis was implemented to measure the protein levels of OTX1, VEGFA, and key factors involved in the MAPK signaling pathway. The concentrations of oxidative stress markers (superoxide dismutase, catalase, and lipid hydroperoxide) in AECs and placental tissues of RUPP rats were measured by corresponding kits. The binding relation between miR-195-5p and OTX1 was verified using the dual-luciferase reporter assay. Hematoxylin-eosin staining was conducted to evaluate the pathological features of rat placental tissues. MiR-195-5p was downregulated, while OTX1 was upregulated in rat placental tissues and human serum samples of PIH patients. MiR-195-5p could target OTX1 and inversely regulate OTX1 expression in AECs and rat placental tissues. In addition, miR-195-5p can negatively regulate VEGFA level. Furthermore, miR-195-5p inactivates oxidative stress and the MAPK signaling by downregulating OTX1 in AECs. In vivo experiments revealed that OTX1 overexpression reversed the protective effect of miR-195-5p overexpression on placental damage and oxidative stress. MiR-195-5p alleviates PIH by inhibiting oxidative stress via targeting OTX1 and inactivating MAPK signaling.

OTX Genes in Adult Tissues

OTX homeobox genes have been extensively studied for their role in development, especially in neuroectoderm formation. Recently, their expression has also been reported in adult physiological and pathological tissues, including retina, mammary and pituitary glands, sinonasal mucosa, in several types of cancer, and in response to inflammatory, ischemic, and hypoxic stimuli. Reactivation of OTX genes in adult tissues supports the notion of the evolutionary amplification of functions of genes by varying their temporal expression, with the selection of homeobox genes from the "toolbox" to drive or contribute to different processes at different stages of life. OTX involvement in pathologies points toward these genes as potential diagnostic and/or prognostic markers as well as possible therapeutic targets.

Early detection of hepatocellular carcinoma via no end-repair enzymatic methylation sequencing of cell-free DNA and pre-trained neural network

BACKGROUND

Early detection of hepatocellular carcinoma (HCC) is important in order to improve patient prognosis and survival rate. Methylation sequencing combined with neural networks to identify cell-free DNA (cfDNA) carrying aberrant methylation offers an appealing and non-invasive approach for HCC detection. However, some limitations exist in traditional methylation detection technologies and models, which may impede their performance in the read-level detection of HCC.

METHODS

We developed a low DNA damage and high-fidelity methylation detection method called No End-repair Enzymatic Methyl-seq (NEEM-seq). We further developed a read-level neural detection model called DeepTrace that can better identify HCC-derived sequencing reads through a pre-trained and fine-tuned neural network. After pre-training on 11 million reads from NEEM-seq, DeepTrace was fine-tuned using 1.2 million HCC-derived reads from tumor tissue DNA after noise reduction, and 2.7 million non-tumor reads from non-tumor cfDNA. We validated the model using data from 130 individuals with cfDNA whole-genome NEEM-seq at around 1.6X depth.

RESULTS

NEEM-seq overcomes the drawbacks of traditional enzymatic methylation sequencing methods by avoiding the introduction of unmethylation errors in cfDNA. DeepTrace outperformed other models in identifying HCC-derived reads and detecting HCC individuals. Based on the whole-genome NEEM-seq data of cfDNA, our model showed high accuracy of 96.2%, sensitivity of 93.6%, and specificity of 98.5% in the validation cohort consisting of 62 HCC patients, 48 liver disease patients, and 20 healthy individuals. In the early stage of HCC (BCLC 0/A and TNM I), the sensitivity of DeepTrace was 89.6 and 89.5% respectively, outperforming Alpha Fetoprotein (AFP) which showed much lower sensitivity in both BCLC 0/A (50.5%) and TNM I (44.7%).

CONCLUSIONS

By combining high-fidelity methylation data from NEEM-seq with the DeepTrace model, our method has great potential for HCC early detection with high sensitivity and specificity, making it potentially suitable for clinical applications. DeepTrace: https://github.com/Bamrock/DeepTrace.

Orthodenticle Homeobox OTX1 Promotes Papillary Thyroid Carcinoma Progression and Is a Potential Prognostic Biomarker

Papillary thyroid carcinoma (PTC) is the most common type of thyroid neoplasms, characterized by evidence of follicular cell differentiation. Orthodenticle homeobox 1 (OTX1) is a transcription factor which has been implicated in numerous diseases, including malignancies. The objective of this research was to explore the function of OTX1 in PTC. Immunohistochemistry (IHC) was employed to determine the protein level of OTX1 in PTC specimens. Cell viability was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Furthermore, a xenograft model on nude mice was established to investigate in vivo effects of OTX1. Our results revealed that OTX1 was significantly upregulated within specific PTC tissues and was remarkably correlated with unfavorable clinical outcomes in PTC. Silencing OTX1 resulted in a significant inhibition in cell viability and suppressed cell proliferation. In addition, in vivo experiments demonstrated that OTX1 silencing resulted in a significant suppression of tumor growth in nude mice. Collectively, these results suggest that OTX1 may play crucial roles in promoting PTC progression.

MiR-195-5p suppresses gastric adenocarcinoma cell progression via targeting OTX1

Gastric adenocarcinoma (GAC) caused by malignant transformation of gastric adenocytes is a malignancy with high incidence. MiR-195-5p modulates a variety of cancers. One of its target genes, orthodenticle homeobox 1 (OTX1), is believed to be a key modulator of tumor progression. We aim to analyze the mechanism of miR-195-5p and OTX1 in GAC. MiR-195-5p and OTX1 mRNA levels in GAC cells were tested via qRT-PCR. OTX1 protein and EMT-related protein levels were examined through western blot. Several cell functional assays were designed to measure changes in cell malignant behaviors. Dual luciferase assay verified the targeting relation of miR-195-5p and OTX1. These experimental results showed significantly low miR-195-5p expression and significantly high OTX1 expression in GAC cells. Enforced miR-195-5p level repressed cell malignant progression and accelerated cell apoptosis in GAC. Increased OTX1 weakened the above-mentioned effect caused by overexpressing miR-195-5p. Thus, miR-195-5p restrained migration, proliferation, invasion and epithelial-mesenchymal transition process of GAC cells, and promoted cell apoptosis through regulating OTX1. A new insight is provided for searching for biomarkers or therapeutic targets of GAC.

Taurodeoxycholic acid-YAP1 upregulates OTX1 in promoting gallbladder cancer malignancy through IFITM3-dependent AKT activation

Orthodenticle homeobox (OTX1) is reported to be involved in numerous cancers, but the expression level and molecular function of OTX1 in gallbladder cancer (GBC) remain unknown. Here, we found the elevated level of OTX1 associated with poor prognosis in human gallbladder cancer. In vitro and in vivo studies of human gallbladder cancer cell lines demonstrated that overexpression of OTX1 promoted cell proliferation, whereas the downregulation inhibited it. Additionally, we found a tight correlation between the serum level of taurodeoxycholic acid (TDCA) and OTX1 expression. TDCA-induced activation of YAP1 by phosphorylation inhibition contributed to the transcriptional activation of OTX1. Mechanistically, we identified that OTX1 activated AKT signaling pathway by transactivating the expression of IFITM3 and thus promoted the proliferation of GBC cells. Taken together, our results showed that TDCA-YAP1-dependent expression of OTX1 regulated IFITM3 and affected GBC proliferation via the AKT signaling pathway. Our experiments also suggested that OTX1 is a novel therapeutic target for GBC.

OTX1 silencing suppresses ovarian cancer progression through inhibiting the JAK/STAT signaling

BACKGROUND

The aim of our study was to investigate the roles and the underlying mechanisms of orthodenticle homolog 1 (OTX1) in ovarian cancer.

METHODS

OTX1 expression was obtained from TCGA database. OTX1 expression in ovarian cancer cells was detected using qRT-PCR and western blot assay. The cell viability and proliferation was detected by CCK-8 and EdU assays. Cell invasion and migration were detected by transwell assay. Flow cytometry was utilized to determine cell apoptosis and cycle. In addition, western blot assay was used to detect the expression of cell cycle related protein (Cyclin D1 and p21), epithelial-mesenchymal transition (EMT) related protein (E-cadherin, N-cadherin, Vimentin, and Snail), apoptosis related protein (Bcl-2, Bax, and cleaved caspase-3), and JAK/STAT pathway related protein (p-JAK2, JAK2, STAT3, and p-STAT3).

RESULTS

OTX1 was highly expressed in ovarian cancer tissues and cells. OTX1 silencing blocked the cell cycle and repressed cell viability, proliferation, invasion, and migration, while OTX1 silencing facilitated the apoptosis of OVCAR3 and Caov3 cells. OTX1 silencing increased the protein levels of p21, E-cadherin, Bax, and cleaved caspase-3, while the protein levels of Cyclin D1, Bcl-2, N-cadherin, Vimentin, and Snail were decreased by OTX1 silencing. Furthermore, OTX1 silencing suppressed the protein levels of p-JAK2/JAK2 and p-STAT3/STAT3 in OVCAR3 and Caov3 cells. Moreover, overexpression of OTX1 promoted cell proliferation and invasion and inhibited apoptosis in Caov3 cells, but AG490 (an inhibitor of JAK/STAT pathway) reversed the influences on cell biological behavior induced by overexpression of OTX1.

CONCLUSIONS

OTX1 silencing repressed ovarian cancer cell proliferation, invasion, and migration and induced cell apoptosis, which might be involved in JAK/STAT signaling pathway. OTX1 may be considered as a novel therapeutic target for ovarian cancer.

MicroRNA-4516 suppresses proliferative vitreoretinopathy development via negatively regulating OTX1

Proliferative vitreoretinopathy (PVR) progression is associated with TGF-β2-induced epithelial–mesenchymal transition (EMT) in retinal pigment epithelial (RPE) cells. In cancer cells, miR-4516 downregulates orthodenticle homeobox 1 (OTX1)-mediated cell invasion. Moreover, OTX1 is shown to be involved in invasion and EMT. The purpose of this study was to assess whether microRNA (miR-4516) suppresses EMT in RPE cells. EMT features were assessed using Western blotting, immunocytochemical staining, scratch-wound healing, modified Boyden chamber assay, and collagen gel contraction assay. For in vivo testing, a rabbit model was used, which involved induction of PVR by injection of transfected spontaneously arising RPE (ARPE) cells into the vitreous chamber. The putative target of miR-4516 was identified by luciferase reporter assay. Results showed that TGF-β2-induced transdifferentiation and migration of RPE cells was inhibited by miR-4516 delivery. Overexpression of miR-4516 led to upregulation of zonula occludens-1, downregulation of α-smooth muscle actin and vimentin, and cell contractility—all EMT features—in the TGF-β2-treated ARPE-19 cells. MiR-4516 regulated OTX1 expression negatively by binding to its 3’-UTR. TGF-β2-induced phosphorylated ERK was inhibited in miR-4516-overexpressing ARPE-19 cells. MiR-4516 suppressed experimental PVR in vitro and in vivo. In conclusion, the overexpression of miR-4516 suppresses TGF-β2-induced EMT in a PVR model, and its role in PVR depends on OTX1/ERK. Further research is needed to develop a feasible treatment method to prevent and treat PVR.

Knockdown of circMYOF inhibits cell growth, metastasis, and glycolysis through miR-145-5p/OTX1 regulatory axis in laryngeal squamous cell carcinoma

New evidence suggests that abnormal expression of circular RNA (circRNA) is associated with the development of human cancers. This study aims to reveal circMYOF roles in the malignant phenotype of laryngeal squamous cell carcinoma (LSCC). The expression of circMYOF, microRNA (miR)-145-5p, and orthodenticle homeobox 1 (OTX1) was detected by quantitative real-time PCR. Cell proliferation, migration, invasion, and apoptosis were determined using colony formation assay and EdU assay, wound healing assay, transwell assay, and flow cytometry, respectively. Protein expression was examined by western blot analysis. Cell glycolysis was assessed by detecting glucose consumption and lactate production. Mice xenograft models were constructed to evaluate the regulation of circMYOF on LSCC tumorigenesis. The regulatory relationships among circMYOF, miR-145-5p, and OTX1 were identified using dual-luciferase reporter assay and RIP assay. Serum exosomes were isolated to confirm the existence of circMYOF in LSCC patients. CircMYOF was upregulated in LSCC tissues and cells, and its knockdown suppressed LSCC cell growth, metastasis, and glycolysis, as well as inhibited LSCC tumor growth. MiR-145-5p had decreased expression in LSCC, and it could be sponged by circMYOF. The inhibition effect of circMYOF lentivirus short hairpin RNA (sh-circMYOF) on LSCC progression was restored by the inhibitor of miR-145-5p (in-miR-145-5p). Also, OTX1 was targeted by miR-145-5p and was positively regulated by circMYOF. MiR-145-5p could repress LSCC progression, and OTX1 overexpression also eliminated this effect. In addition, we found that circMYOF was significantly overexpressed in the serum exosomes of LSCC patients. Our data revealed that circMYOF contributed to LSCC progression by promoting cell growth, metastasis, and glycolysis through miR-145-5p/OTX1 axis.

Genetic Regulation of Vertebrate Forebrain Development by Homeobox Genes

Forebrain development in vertebrates is regulated by transcription factors encoded by homeobox, bHLH and forkhead gene families throughout the progressive and overlapping stages of neural induction and patterning, regional specification and generation of neurons and glia from central nervous system (CNS) progenitor cells. Moreover, cell fate decisions, differentiation and migration of these committed CNS progenitors are controlled by the gene regulatory networks that are regulated by various homeodomain-containing transcription factors, including but not limited to those of the Pax (paired), Nkx, Otx (orthodenticle), Gsx/Gsh (genetic screened), and Dlx (distal-less) homeobox gene families. This comprehensive review outlines the integral role of key homeobox transcription factors and their target genes on forebrain development, focused primarily on the telencephalon. Furthermore, links of these transcription factors to human diseases, such as neurodevelopmental disorders and brain tumors are provided.

Orthodenticle homeobox OTX1 is a potential prognostic biomarker for bladder cancer

Bladder cancer (BC) is one of the most aggressive tumors worldwide. OTX1 (orthodenticle homeobox 1) is an important transcription factor involved in various diseases, such as cancers. The aim of this study was to further investigate the role of OTX1 in BC. In this study, differentially expressed genes (DEGs) were screened from tumor tissues and para-cancerous tissues by bioinformatics. The expression of protein and RNA was separately detected by western blotting and immunohistochemistry (IHC), and quantitative polymerase chain reaction (qPCR); cell viability and cell growth were determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and clone formation assays, respectively; cell motility was measured by transwell and wound healing assays; cell cycle was measured by flow cytometry. In this study, 9 DEGs were screened out, and OTX1 was employed as a candidate gene for subsequent study. Results found that OTX1 was highly expressed in BC cells and BC tissues, which was significantly associated with poor prognosis of patients. In addition, OTX1 silencing significantly reduced cell viability, and inhibited cell growth and motility, while OTX1 overexpression got opposite results. Moreover, OTX1 co-expressed genes were enriched in cell cycle-related pathways, suggesting that the role of OTX1 in BC may be related to cell cycle, which was confirmed by flow cytometry analysis. Furthermore, in vivo experiments showed that OTX1 silencing significantly inhibited tumor growth in tumor-bearing mice. Taken together, our findings suggested that OTX1 may play a promotional role in BC progression.

A Co-Expression Network Reveals the Potential Regulatory Mechanism of lncRNAs in Relapsed Hepatocellular Carcinoma

Background

The mechanistic basis for relapsed hepatocellular carcinoma (HCC) remains poorly understood. Recent research has highlighted the important roles of long non-coding RNAs (lncRNAs) in HCC. However, there are only a few studies on the association between lncRNAs and HCC relapse.

Methods

Differentially expressed lncRNAs and mRNAs between a primary HCC group and relapsed HCC group were identified using the edge R package to analyze the GSE101432 dataset. The differentially expressed lncRNAs and mRNAs were used to construct a lncRNA–mRNA co-expression network. Weighted gene co-expression network analysis followed by Gene Ontology (GO) enrichment analyses were conducted on the database. Furthermore, correlation and survival analyses were performed using The Cancer Genome Atlas database, and expression in the clinical samples was verified by qRT-PCR. Thereafter, we inputted the genes from the two groups into the HCC TNM stage and tumor grade database from TCGA. Finally, we performed Kaplan–Meier survival analysis on the lncRNAs related to relapsed HCC.

Results

In this study, lncRNAs and mRNAs associated with HCC relapse were identified. Two gene modules were found to be closely linked to this. The GO terms in the yellow and black modules were related to cell proliferation, differentiation, and survival, as well as some transcription-related biological processes. Through qRT-PCR, we found that the expression levels of LINC00941 and LINC00668 in relapsed HCC were higher than those in primary HCC. Further, mRNA levels of LOX, OTX1, MICB, NDUFA4L2, BAIAP2L2, and KCTD17 were changed in relapsed HCC compared to levels in primary HCC. In addition, we verified that these genes could predict the overall survival and recurrence-free survival of HCC. Moreover, we found that LINC00668 and LINC00941 could affect tumor grade and TNM stages. In total, we identified and validated two lncRNAs (LINC00941 and LINC00668) and six mRNAs (LOX, MICB, OTX1, BAIAP2L2, KCTD17, NDUFA4L2) associated with HCC relapse.

Conclusion

In summary, we identified the key gene modules and central genes associated with relapsed HCC and constructed lncRNA–mRNA networks related to this. These genes are likely to have potential prognostic value for relapsed HCC and might shed new light on novel biomarkers or diagnostic targets for relapsed HCC.

miR-223-5p Suppresses OTX1 to Mediate Malignant Progression of Lung Squamous Cell Carcinoma Cells

BACKGROUND

Lung squamous cell carcinoma (LUSC) features high morbidity and mortality as a worldwide malignant tumor. This study mainly explored a miR-223-5p-dependent mechanism that affected proliferation, invasion, and migration of LUSC cells.

METHODS

Expression data of mature miRNAs and sequencing data of total RNA of LUSC were downloaded from TCGA database. Differentially expressed mRNAs were obtained. Function of miR-223-5p in LUSC cells was detected by assays like qRT-PCR, MTT, wound healing assay, Western blot, and Transwell assay. Western blot was performed to analyze the relationship between OTX1 and JAK/STAT signaling pathways. Dual-luciferase assay detected the relationship between miR-223-5p and OTX1. The way how miR-223-5p regulated LUSC cell biological functions via OTX1 was further explored.

RESULTS

It was noted that miR-223-5p expression in LUSC tissue and cells was significantly reduced. Overexpression of miR-223-5p negatively regulated the proliferation, invasion, and migration of LUSC cells. The downstream target gene OTX1 was detected to be notably elevated in LUSC cells. A negative correlation between OTX1 and miR-223-5p was also found. As analyzed by GSEA, OTX1 was significantly enriched in the JAK/STAT signaling pathway and activated the pathway. Dual-luciferase assay demonstrated that OTX1 was a direct molecular target of miR-223-5p in LUSC cells. Rescue experiment verified that miR-223-5p regulated the malignant phenotypes of LUSC cells by pairing with OTX1.

CONCLUSION

This study indicated that miR-223-5p was lowly expressed in LUSC cells. The impact of miR-223-5p on cell proliferation, invasion, and migration was realized by targeting OTX1. It is likely that miR-223-5p can be a novel target for LUSC treatment, which provides new ideas for future LUSC treatment.

MiR-4269 suppresses the tumorigenesis and development of pancreatic cancer by targeting ZEB1/OTX1 pathway

As one of the most prevalent malignant tumors, pancreatic cancer (PC) is a leading fatal cancer worldwide. Surging evidence has unraveled that miRNAs are involved in the occurrence and progression of multiple cancers, including PC. The tumor suppressor effects of miR-4269 have been certified in gastric carcinoma. However, the potential function of miR-4269 remains largely unclear, which drives us to identify the role of miR-4269 in PC development. In the present study, we determined the expression pattern of miR-4269 in PC cells and normal cells. Results of RT-qPCR analysis illuminated that miR-4269 expression level in PC cells was lower than that in normal cells. Functional assays demonstrated that up-regulation of miR-4269 obviously inhibited the proliferation, migration and invasion of PC cells. In order to elucidate the mechanism governing miR-4269 in PC, we carried out bioinformatics analysis and further experimental investigations. Our results validated that ZEB1 was a direct target of miR-4269. Additionally, ZEB1 activated the transcription of OXT1. More importantly, miR-4269 attenuated the expression level of OXT1 via targeting ZEB1. Ultimately, our findings confirmed that miR-4269 served as a cancer suppressor in PC through regulation of ZEB1/OTX1 pathway, which suggested that miR-4269 might represent a promising target for the clinical treatment of PC.

Long non-coding RNA MIR100HG promotes the migration, invasion and proliferation of triple-negative breast cancer cells by targeting the miR-5590-3p/OTX1 axis

Background

As an aggressive subtype of breast cancer with a high risk of recurrence, triple-negative breast cancer (TNBC) lacks available treatment targets. LncRNA MIR100HG promotes cell proliferation in TNBC. However, few studies have investigated the molecular mechanism of MIR100HG in TNBC. Thus, additional in-depth investigations are needed to unravel its associated regulatory mechanism.

Methods

MIR100HG and miR-5590-3p expression in TNBC tissue samples and cell lines was detected by RT-qPCR. Flow cytometry, transwell, wound-healing, CCK8 and colony formation assays were performed to analyse cell apoptosis, cell cycle, invasion, migration and proliferation. The protein expression of orthodenticle homeobox 1 (OTX1) and proteins in the ERK/MAPK signalling pathway were assessed by western blot analysis. Bioinformatics and luciferase assay were performed to predict and validate the interaction between MIR100HG and miR-5590-3p as well as OTX1 and miR-5590-3p. RNA immunoprecipitation (RIP) was used to detect the interaction between MIR100HG and miR-5590-3p. Subcutaneous tumour growth was observed in nude mice. Immunohistochemistry (IHC) analysis was used to assess OTX1 expression in tumour tissues.

Results

MIR100HG expression was upregulated, whereas that of miR-5590-3p was downregulated in TNBC. MIR100HG was shown to directly interact with miR-5590-3p. Furthermore, MIR100HG knockdown could promote TNBC cell apoptosis and cell cycle arrest in G0/G1 phase while inhibiting migration, invasion and proliferation. Furthermore, miR-5590-3p inhibition showed the opposite results and could reverse the effect of MIR100HG knockdown in TNBC cells. MiR-5590-3p downregulated the ERK/MAPK signalling pathway, suppressed the migration, invasion and proliferation of TNBC cells and promoted their apoptosis and cell cycle arrest in G0/G1 phase by targeting OTX1. In addition, MIR100HG knockdown inhibited OTX1 expression by upregulating miR-5590-3p in vivo, thereby inhibiting tumour growth.

Conclusions

MIR100HG promotes the progression of TNBC by sponging miR-5590-3p, thereby upregulating OTX1, suggesting a new potential treatment target for TNBC.

OTX1 exerts an oncogenic role and is negatively regulated by miR129-5p in laryngeal squamous cell carcinoma

Background

Orthodenticle homeobox 1 (OTX1) is a transcription factor that plays an important role in various human cancers. However, the function of OTX1 in laryngeal squamous cell carcinoma (LSCC) is largely unknown. We aimed to explore the roles of OTX1 in LSCC and its possible molecular mechanism.

Methods

The expression levels of OTX1 were assessed in LSCC cell lines and tissue samples. We further examined the effect of OTX1 on LSCC progression. The upstream regulator of OTX1 was identified using a computer algorithm and confirmed experimentally.

Results

OTX1 was highly expressed in 70.7% (70/99) of LSCC tissue samples. The OTX1 expression in LSCC was significantly correlated with lymph node metastasis. High OTX1 expression in patients with LSCC was correlated with poor prognosis. Knockdown of OTX1 inhibited proliferation, colony formation, migration and invasion in LSCC cells. Knockdown of OTX1 inhibited tumor growth in a xenograft mouse model. Mechanistically, OTX1 might act as a direct target of miR-129-5p. OTX1 enhanced tumorigenicity and tumor growth both in vitro and in vivo.

Conclusions

Our findings support that OTX1 is an oncogene in LSCC tumorigenesis and progression. Furthermore, OTX1 is a direct target of miR-129-5p in LSCC cells. Taken together, OTX1 is a promising diagnostic and therapeutic marker for LSCC.

A Genetic Screen for Human Genes Suppressing FUS Induced Toxicity in Yeast

FUS is a nucleic acid binding protein that, when mutated, cause a subset of familial amyotrophic lateral sclerosis (ALS). Expression of FUS in yeast recapitulates several pathological features of the disease-causing mutant proteins, including nuclear to cytoplasmic translocation, formation of cytoplasmic inclusions, and cytotoxicity. Genetic screens using the yeast model of FUS have identified yeast genes and their corresponding human homologs suppressing FUS induced toxicity in yeast, neurons and animal models. To expand the search for human suppressor genes of FUS induced toxicity, we carried out a genome-scale genetic screen using a newly constructed library containing 13570 human genes cloned in an inducible yeast-expression vector. Through multiple rounds of verification, we found 37 human genes that, when overexpressed, suppress FUS induced toxicity in yeast. Human genes with DNA or RNA binding functions are overrepresented among the identified suppressor genes, supporting that perturbations of RNA metabolism is a key underlying mechanism of FUS toxicity.

MicroRNA-4516 suppresses pancreatic cancer development via negatively regulating orthodenticle homeobox 1

Pancreatic cancer remains one of the most lethal human cancers without efficient therapeutic strategy. MicoRNAs (miRNAs) are a group of small non-coding RNAs involved in multiple biological processes including tumor development and progression. In this study, we investigated the expression and function of miR-4516 in pancreatic cancer. MiR-4516 was low-expressed in pancreatic cancer tissues and cell lines. Overexpression of miR-4516 inhibited pancreatic cancer cell proliferation, migration and invasion, while promoted cell apoptosis in vitro. Further, overexpression of miR-4516 suppressed xenograft pancreatic tumor growth in vivo. Bioinformatics analysis was performed and miR-4516 was predicted to negatively regulate orthodenticle homeobox 1 (OTX1) expression by binding to its 3'-UTR. Consistently, OTX1 was highly expressed in pancreatic cancer tissues and cell lines. Knockdown of OTX1 expression suppressed pancreatic cancer cell migration and invasion, with down-regulated MMP2 and MMP9 expression. Moreover, we demonstrated that miR-4516 regulated pancreatic cancer cell growth, migration, invasion and apoptosis via targeting OTX1. Overexpression of OTX1 could partially abrogate the inhibitory effect of miR-4516. Taken together, we conclude that miR-4516 could function as a tumor suppressor via targeting OTX1. These findings suggest that miR-4516/OTX1 axis might be a novel therapeutic target for miRNA-based therapy for pancreatic cancer patients.

Long non-coding RNA HNF1A-AS1 upregulates OTX1 to enhance angiogenesis in colon cancer via the binding of transcription factor PBX3

Colon cancer shows characteristics of metastasis, which is associated with angiogenesis. Increasing evidence highlights long non-coding RNAs (lncRNAs) as important participants in angiogenesis of cancers, including colon cancer. Hence, this study investigated the role of HNF1A-AS1 in angiogenesis of colon cancer. RT-qPCR and Western blot analysis were applied to detect HNF1A-AS1 and OTX1 expression in colon cancer tissues and cell lines. Then the interactions among HNF1A-AS1, PBX3, OTX1 and ERK/MAPK pathway were evaluated with RNA pull-down, RIP, ChIP and dual-luciferase reporter gene assays. Next, HCT116 and SW620 cells were treated with si-HNF1A-AS1 and/or oe-OTX1 plasmids to assess the effects of HNF1A-AS1 and OTX1 on angiogenesis, which was further evaluated in nude mice injected with SW620 cells transfected with sh-HNF1A-AS1 or sh-OTX1 lentivirus. HNF1A-AS1 and OTX1 were highly expressed in colon cancer. Silencing of HNF1A-AS1 inhibited angiogenesis of colon cancer in vivo and in vitro. HNF1A-AS1 increased the OTX1 expression by binding to transcription factor PBX3 to promote angiogenesis in colon cancer. Further, HNF1A-AS1 upregulated OTX1 to activate the ERK/MAPK pathway. Altogether, our findings identified HNF1A-AS1 as a tumor-promoting RNA in colon cancer, which could serve as a potential therapeutic target for colon cancer treatment.

The lncRNA FEZF1-AS1 Promotes the Progression of Colorectal Cancer Through Regulating OTX1 and Targeting miR-30a-5p

Long noncoding RNAs (lncRNAs) participate in and regulate the biological process of colorectal cancer (CRC) progression. Our previous research identified differentially expressed lncRNAs in 10 CRC tissues and 10 matched nontumor tissues by next-generation sequencing (NGS). In this study, we identified an lncRNA, FEZF1 antisense RNA 1 (FEZF1-AS1), and further explored its function and mechanism in CRC. We verified that FEZF1-AS1 is highly expressed in CRC tissues and cell lines. Through functional experiments, we found that reduced levels of FEZF1-AS1 significantly suppressed CRC cell migration, invasion, and proliferation and inhibited tumor growth in vivo. Mechanistically, we discovered that reduced levels of the lncRNA FEZF1-AS1 inhibited the activation of epithelial-mesenchymal transition (EMT); the overexpression of orthodenticle homeobox 1 (OTX1) partially rescued the FEZF1-AS1-induced inhibition of protein expression. It indicated that FEZF1-AS1 may play a role in the occurrence and development of CRC by regulating the FEZF1-AS1/OTX1/EMT pathway. Furthermore, it was reported that FEZF1-AS1 is located in both the nucleus and cytoplasm of HCT116 cells. Dual-luciferase reporter assays verified that FEZF1-AS1 directly binds miR-30a-5p and negatively regulated each other. Further, we showed that 5'-nucleotidase ecto (NT5E) is a direct target of miR-30a-5p, and the inhibition of miR-30a-5p expression partially rescued the inhibitory effect of FEZF1-AS1 on NT5E. Our results indicated that the mechanism by which FEZF1-AS1 positively regulates the expression of NT5E is through sponging miR-30a-5p. Our study demonstrated that lncRNA FEZF1-AS1 is involved in the development of CRC and may serve as a diagnostic and therapeutic target for CRC patients.

Identification of a 5-Gene Signature Predicting Progression and Prognosis of Clear Cell Renal Cell Carcinoma

Background

Although the mortality rates of clear cell renal cell carcinoma (ccRCC) have decreased in recent years, the clinical outcome remains highly dependent on the individual patient. Therefore, identifying novel biomarkers for ccRCC patients is crucial.

Material/Methods

In this study, we obtained RNA sequencing data and clinical information from the TCGA database. Subsequently, we performed integrated bioinformatic analysis that includes differently expressed genes analysis, gene ontology and KEGG pathway analysis, protein-protein interaction analysis, and survival analysis. Moreover, univariate and multivariate Cox proportional hazards regression models were constructed.

Results

As a result, we identified a total of 263 dysregulated genes that may participate in the metastasis of ccRCC, and established a predictive signature relying on the expression of OTX1, MATN4, PI3, ERVV-2, and NFE4, which could serve as significant progressive and prognostic biomarkers for ccRCC.

Conclusions

We identified differentially expressed genes that may be involved in the metastasis of ccRCC. Moreover, a predictive signature based on the expression of OTX1, MATN4, PI3, ERVV-2, and NFE4 could be an independent prognostic factor for ccRCC.

Dowregulation of OTX1 attenuates gastric cancer cell proliferation, migration and invasion

Orthodenticle homolog 1 (OTX1) has previously been revealed to be tightly associated with the development and progression of several human tumors. However, the functional roles and underlying molecular mechanisms of OTX1 in gastric cancer (GC) remain poorly understood. In the present study, we observed that OTX1 was highly expressed in GC tissues compared with adjacent non-tumor tissues based on a large cohort of samples from The Cancer Genome Atlas (TCGA) database. An immunohistochemical analysis indicated that OTX1 levels were increased in tumors that became metastatic compared with those in tumors that did not. This finding was significantly associated with patients who had shorter overall survival times. The knockdown of OTX1 significantly inhibited the proliferation, migration and invasion of SGC-7901 and MGC-803 cells. Furthermore, the knockdown of OTX1 induced cell cycle arrest in the G₀/G₁ phase and reduced the expression of cyclin D1. In addition, the inhibition of OTX1 led to increased GC cell apoptosis by upregulating cleaved PARP, cleaved caspase-3 and Bax. In conclusion, our data indicated that OTX1 functions as a key regulator in tumor growth and metastasis of GC cells. Thus, OTX1 may be a promising novel target for molecular therapy directed toward GC.

High-throughput analysis reveals novel maternal germline RNAs crucial for primordial germ cell preservation and proper migration

During oogenesis, hundreds of maternal RNAs are selectively localized to the animal or vegetal pole, including determinants of somatic and germline fates. Although microarray analysis has identified localized determinants, it is not comprehensive and is limited to known transcripts. Here, we utilized high-throughput RNA-sequencing analysis to comprehensively interrogate animal and vegetal pole RNAs in the fully grown Xenopus laevis oocyte. We identified 411 (198 annotated) and 27 (15 annotated) enriched mRNAs at the vegetal and animal pole, respectively. Ninety were novel mRNAs over 4-fold enriched at the vegetal pole and six were over 10-fold enriched at the animal pole. Unlike mRNAs, microRNAs were not asymmetrically distributed. Whole-mount in situ hybridization confirmed that all 17 selected mRNAs were localized. Biological function and network analysis of vegetally enriched transcripts identified protein-modifying enzymes, receptors, ligands, RNA-binding proteins, transcription factors and co-factors with five defining hubs linking 47 genes in a network. Initial functional studies of maternal vegetally localized mRNAs show that sox7 plays a novel and important role in primordial germ cell (PGC) development and that ephrinB1 (efnb1) is required for proper PGC migration. We propose potential pathways operating at the vegetal pole that highlight where future investigations might be most fruitful.

A qRT-PCR and Gene Functional Enrichment Study Focused on Downregulation of miR-141-3p in Hepatocellular Carcinoma and Its Clinicopathological Significance

BACKGROUND

The clinical significance of miR-141-3p in hepatocellular carcinoma has not been verified. Therefore, we conducted this study to examine miR-141-3p expression and its clinical significance in hepatocellular carcinoma and to investigate the functions of its potential targets.

METHODS

The Cancer Genome Atlas database and the Gene Expression Omnibus database were used to explore the aberrant expression of miR-141-3p in hepatocellular carcinoma. Furthermore, we assessed the miR-141-3p levels in 95 hepatocellular carcinoma tissues with 95 matched adjacent tissues using real-time quantitative polymerase chain reaction. Moreover, a target gene prediction analysis of miR-141-3p, a natural language processing analysis for hepatocellular carcinoma using PubMed, and a gene functional enrichment analysis were conducted to search the potential function of miR-141-3p in the pathogenesis of hepatocellular carcinoma.

RESULTS

Regarding The Cancer Genome Atlas data, miR-141-3p levels were markedly downregulated in hepatocellular carcinoma tissue compared to para- or nontumor tissue (4.6112 [1.7096] vs 5.3053 [1.4254], P = .045). MiR-141-3p expression was reduced in patients with hepatocellular carcinoma with a low pathologic T stage (P = .006), a low grade (P = .01), elderly hepatocellular carcinoma patients (P = .001), and male patients with hepatocellular carcinoma (P = .01) compared with that in patients with hepatocellular carcinoma with high pathologic T stages, high grades, young patients with hepatocellular carcinoma, and female patients with hepatocellular carcinoma. However, according to the Gene Expression Omnibus database, no significant differences in the expression of miR-141-3p were observed between hepatocellular carcinoma tissue and normal liver tissue (P = .984). Real-time quantitative polymerase chain reaction confirmed a similar trend of decreased miR-141-3p in hepatocellular carcinoma tissue (1.7542 [0.8663] vs 2.5562 [1.7913], P = .001) as observed in The Cancer Genome Atlas. In addition, decreased miR-141-3p levels were detected in the multiple tumor nodes group (P = .004), the metastasis group (P < .001), and the advanced TNM stage group (P = .01), compared to the single tumor nodes group, the nonmetastasis group, and the early TNM stage group. Two hundred eighty-two genes were identified from the overlap between the predicted targets and the natural language processing analysis. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed several significant biological functions and pathways related to the pathogenesis of cancers, including hepatocellular carcinoma.

CONCLUSION

Downregulation of miR-141-3p might be responsible for the carcinogenesis and aggressiveness of hepatocellular carcinoma. MiR-141-3p may act as an antitumor microRNA, which is essential for hepatocellular carcinoma progression through the regulation of various signaling pathways. Thus, interactions with miR-141-3p may provide a novel strategy for hepatocellular carcinoma treatment in the future.