Oct4 induces EMT through LEF1/β-catenin dependent WNT signaling pathway in hepatocellular carcinoma

Octamer-binding transcription factor 4-positive circulating tumor cell predicts worse treatment response and survival in advanced cholangiocarcinoma patients who receive immune checkpoint inhibitors treatment

BACKGROUND

Octamer-binding transcription factor 4-positive circulating tumor cell (OCT4+CTC) exhibits high stemness and invasive potential, which may influence the efficacy of immune checkpoint inhibitors (ICI). This study aimed to assess the prognostic role of OCT4+CTC in advanced cholangiocarcinoma (CCA) patients who received ICI treatment.

METHODS

In total, 40 advanced CCA patients who received ICI treatment were included, and CTC and OCT4 counts were detected via a Canpatrol system and an RNA in situ hybridization method before ICI treatment. Patients were subsequently divided into none CTC, OCT4-CTC, and OCT4+CTC groups. Patients were followed up for a median of 10.4 months.

RESULTS

The percentages of patients in none CTC, OCT4-CTC, and OCT4+CTC groups were 25.0%, 30.0%, and 45.0%, respectively. The proportion of patients with lymph node metastasis was highest in OCT4+CTC group, followed by none CTC group, and lowest in OCT4-CTC group (P = 0.025). The objective response rate (ORR) was lowest in OCT4+CTC group, moderate in OCT4-CTC group, and highest in none CTC group (P = 0.009), while disease control rate was not different among three groups (P = 0.293). In addition, progression-free survival (PFS) (P < 0.001) and overall survival (OS) (P = 0.001) were shorter in the OCT4+CTC group than in none CTC & OCT4-CTC group. Moreover, OCT4+CTC (versus none CTC) was independently linked with poorer PFS [hazard ratio (HR) = 6.752, P = 0.001] and OS (HR = 6.674, P = 0.003) in advanced CCA patients.

CONCLUSION

OCT4+CTC relates to lymph node metastasis and shows a good predictive value for poor treatment response and survival in advanced CCA patients who receive ICI treatment.

Pseudogene OCT4-pg5 upregulates OCT4B expression to promote bladder cancer progression by competing with miR-145-5p

Bladder cancer (BC) is one of the most common malignant neoplasms worldwide. Competing endogenous RNA (ceRNA) networks may identify potential biomarkers associated with the progression and prognosis of BC. The OCT4-pg5/miR-145-5p/OCT4B ceRNA network was found to be related to the progression and prognosis of BC. OCT4-pg5 expression was significantly higher in BC cell lines than in normal bladder cells, with OCT4-pg5 expression correlating with OCT4B expression and advanced tumor grade. Overexpression of OCT4-pg5 and OCT4B promoted the proliferation and invasion of BC cells, whereas miR-145-5p suppressed these activities. The 3' untranslated region (3'UTR) of OCT4-pg5 competed for miR-145-5p, thereby increasing OCT4B expression. In addition, OCT4-pg5 promoted epithelial-mesenchymal transition (EMT) by activating the Wnt/β-catenin pathway and upregulating the expression of matrix metalloproteinases (MMPs) 2 and 9 as well as the transcription factors zinc finger E-box binding homeobox (ZEB) 1 and 2. Elevated expression of OCT4-pg5 and OCT4B reduced the sensitivity of BC cells to cisplatin by reducing apoptosis and increasing the proportion of cells in G1. The OCT4-pg5/miR-145-5p/OCT4B axis promotes the progression of BC by inducing EMT via the Wnt/β-catenin pathway and enhances cisplatin resistance. This axis may represent a therapeutic target in patients with BC.

Wnt/β-catenin-driven EMT regulation in human cancers

Metastasis accounts for 90% of cancer-related deaths among the patients. The transformation of epithelial cells into mesenchymal cells with molecular alterations can occur during epithelial-mesenchymal transition (EMT). The EMT mechanism accelerates the cancer metastasis and drug resistance ability in human cancers. Among the different regulators of EMT, Wnt/β-catenin axis has been emerged as a versatile modulator. Wnt is in active form in physiological condition due to the function of GSK-3β that destructs β-catenin, while ligand-receptor interaction impairs GSK-3β function to increase β-catenin stability and promote its nuclear transfer. Regarding the oncogenic function of Wnt/β-catenin, its upregulation occurs in human cancers and it can accelerate EMT-mediated metastasis and drug resistance. The stimulation of Wnt by binding Wnt ligands into Frizzled receptors can enhance β-catenin accumulation in cytoplasm that stimulates EMT and related genes upon nuclear translocation. Wnt/β-catenin/EMT axis has been implicated in augmenting metastasis of both solid and hematological tumors. The Wnt/EMT-mediated cancer metastasis promotes the malignant behavior of tumor cells, causing therapy resistance. The Wnt/β-catenin/EMT axis can be modulated by upstream mediators in which non-coding RNAs are main regulators. Moreover, pharmacological intervention, mainly using phytochemicals, suppresses Wnt/EMT axis in metastasis suppression.

Downregulation of MAL2 inhibits breast cancer progression through regulating β-catenin/c-Myc axis

PURPOSE

Myelin and lymphocyte protein 2 (MAL2) is mainly involved in endocytosis under physiological conditions and mediates the transport of materials across the membranes of cell and organelle. It has been reported that MAL2 is significantly upregulated in diverse cancers. This study aimed to investigate the role of MAL2 in breast cancer (BC).

METHODS

Bioinformatics analysis and Immunohistochemical assay were applied to detect the correlation between MAL2 expression in breast cancer tissues and the prognosis of breast cancer patients. Functional experiments were carried out to investigate the role of MAL2 in vitro and in vivo. The molecular mechanisms involved in MAL2-induced β-catenin and c-Myc expression and β-catenin/c-Myc-mediated enhancement of BC progression were confirmed by western blot, β-catenin inhibitor and agonist, Co-IP and immunofluorescence colocalization assays.

RESULTS

Results from the cancer genome atlas (TCGA) and clinical samples confirmed a significant upregulation of MAL2 in BC tissues than in adjacent non-tumor tissues. High expression of MAL2 was associated with worse prognosis. Functional experiments demonstrated that MAL2 knockdown reduced the migration and invasion associating with EMT, increased the apoptosis of BC cells in vitro and reduced the metastatic capacity in vivo. Mechanistically, MAL2 interacts with β-catenin in BC cells. MAL2 silencing reduced the expression of β-catenin and c-Myc, while the β-catenin agonist SKL2001 partially rescued the downregulation of c-Myc and inhibition of migration and invasion caused by MAL2 knockdown in BC cells.

CONCLUSION

These observations provided evidence that MAL2 acted as a potential tumor promoter by regulating EMT and β-catenin/c-Myc axis, suggesting potential implications for anti-metastatic therapy for BC.

PRAME Is a Novel Target of Tumor-Intrinsic Gas6/Axl Activation and Promotes Cancer Cell Invasion in Hepatocellular Carcinoma

(1) Background: Activation of the receptor tyrosine kinase Axl by Gas6 fosters oncogenic effects in hepatocellular carcinoma (HCC), associating with increased mortality of patients. The impact of Gas6/Axl signaling on the induction of individual target genes in HCC and its consequences is an open issue. (2) Methods: RNA-seq analysis of Gas6-stimulated Axl-proficient or Axl-deficient HCC cells was used to identify Gas6/Axl targets. Gain- and loss-of-function studies as well as proteomics were employed to characterize the role of PRAME (preferentially expressed antigen in melanoma). Expression of Axl/PRAME was assessed in publicly available HCC patient datasets and in 133 HCC cases. (3) Results: Exploitation of well-characterized HCC models expressing Axl or devoid of Axl allowed the identification of target genes including PRAME. Intervention with Axl signaling or MAPK/ERK1/2 resulted in reduced PRAME expression. PRAME levels were associated with a mesenchymal-like phenotype augmenting 2D cell migration and 3D cell invasion. Interactions with pro-oncogenic proteins such as CCAR1 suggested further tumor-promoting functions of PRAME in HCC. Moreover, PRAME showed elevated expression in Axl-stratified HCC patients, which correlates with vascular invasion and lowered patient survival. (4) Conclusions: PRAME is a bona fide target of Gas6/Axl/ERK signaling linked to EMT and cancer cell invasion in HCC.

Inside the stemness engine: Mechanistic links between deregulated transcription factors and stemness in cancer

Cell identity is largely determined by its transcriptional profile. In tumour, deregulation of transcription factor expression and/or activity enables cancer cell to acquire a stem-like state characterised by capacity to self-renew, differentiate and form tumours in vivo. These stem-like cancer cells are highly metastatic and therapy resistant, thus warranting a more complete understanding of the molecular mechanisms downstream of the transcription factors that mediate the establishment of stemness state. Here, we review recent research findings that provide a mechanistic link between the commonly deregulated transcription factors and stemness in cancer. In particular, we describe the role of master transcription factors (SOX, OCT4, NANOG, KLF, BRACHYURY, SALL, HOX, FOX and RUNX), signalling-regulated transcription factors (SMAD, β-catenin, YAP, TAZ, AP-1, NOTCH, STAT, GLI, ETS and NF-κB) and unclassified transcription factors (c-MYC, HIF, EMT transcription factors and P53) across diverse tumour types, thereby yielding a comprehensive overview identifying shared downstream targets, highlighting unique mechanisms and discussing complexities.

DYNLT3 overexpression induces apoptosis and inhibits cell growth and migration via inhibition of the Wnt pathway and EMT in cervical cancer

The role of the dynein light chain Tctex-type 3 (DYNLT3) protein in the biological behavior of cervical cancer and its relative molecular mechanisms were investigated. Immunohistochemical staining was used to detect DYNLT3 protein expression in cervical cancer tissues. Cell proliferation and apoptosis rates and invasiveness and migratory capacities were determined by CCK-8 assays, BrdU staining assays and colony formation assays, fluorescence activated cell sorting (FACS), wound healing assays, and Transwell invasion assays of cervical cancer cells after DYNLT3 modulation. The expression levels of Wnt signaling pathway- and EMT-related proteins were examined by Western blotting. Furthermore, the effects of DYNLT3 on the tumorigenicity and metastasis of cervical cancer in nude mice were analyzed by performing immunohistochemistry, and we found that the expression level of the DYNLT3 protein was higher in human normal cervical tissues than in cervical cancer tissues. Overexpression of DYNLT3 obviously attenuated the proliferation, migration and invasion of CaSki and SiHa cells, and promoted cell apoptosis. Upregulation of DYNLT3 expression markedly decreased the expression of Wnt signaling pathway-related proteins (Dvl2, Dvl3, p-LRP6, Wnt3a, Wnt5a/b, Naked1, Naked2, β-catenin and C-Myc) and EMT-related proteins (N-cadherin, SOX2, OCT4, vimentin and Snail), and increased the expression of E-cadherin and Axin1. However, the opposite results were observed after down-regulation of DYNLT3 expression. Up-regulation of DYNLT3 expression significantly inhibited tumor growth in a nude mouse model, while downregulation of DYNLT3 showed the opposite results. In addition, the major metastatic site of cervical cancer cells in mice was the lung, and downregulation of DYNLT3 expression increased cancer metastasis in vivo. DYNLT3 exerted inhibitory effects on cervical cancer by inhibiting cell proliferation, migration and invasion, promoting cell apoptosis in vitro, and inhibiting tumor growth and metastasis in vivo, possibly by suppressing the Wnt signaling pathway and the EMT.

OCT4-mediated inflammation induces cell reprogramming at the origin of cardiac valve development and calcification

Cell plasticity plays a key role in embryos by maintaining the differentiation potential of progenitors. Whether postnatal somatic cells revert to an embryonic-like naïve state regaining plasticity and redifferentiate into a cell type leading to a disease remains intriguing. Using genetic lineage tracing and single-cell RNA sequencing, we reveal that Oct4 is induced by nuclear factor κB (NFκB) at embyronic day 9.5 in a subset of mouse endocardial cells originating from the anterior heart forming field at the onset of endocardial-to-mesenchymal transition. These cells acquired a chondro-osteogenic fate. OCT4 in adult valvular aortic cells leads to calcification of mouse and human valves. These calcifying cells originate from the Oct4 embryonic lineage. Genetic deletion of Pou5f1 (Pit-Oct-Unc, OCT4) in the endocardial cell lineage prevents aortic stenosis and calcification of ApoE^−/− mouse valve. We established previously unidentified self-cell reprogramming NFκB- and OCT4-mediated inflammatory pathway triggering a dose-dependent mechanism of valve calcification.

Wnt Signaling Pathway Is among the Drivers of Liver Metastasis

Liver metastasis, originating either from a primary liver or other cancer types, represent a large cancer-related burden. Therefore, studies that add to better understanding of its molecular basis are needed. Herein, the role of the Wnt signaling pathway in liver metastasis is outlined. Its role in hepatocellular carcinoma (HCC) epithelial-mesenchymal transition (EMT), motility, migration, metastasis formation, and other steps of the metastatic cascade are presented. Additionally, the roles of the Wnt signaling pathway in the liver metastasis formation of colorectal, breast, gastric, lung, melanoma, pancreatic, and prostate cancer are explored. The special emphasis is given to the role of the Wnt signaling pathway in the communication between the many of the components of the primary and secondary cancer microenvironment that contribute to the metastatic outgrowth in the liver. The data presented herein are a review of the most recent publications and advances in the field that add to the idea that the Wnt pathway is among the drivers of liver metastasis and that its targeting could potentially relieve liver metastasis–related complications.

A Dimension Reduction Approach for Energy Landscape: Identifying Intermediate States in Metabolism-EMT Network

Dimension reduction is a challenging problem in complex dynamical systems. Here, a dimension reduction approach of landscape (DRL) for complex dynamical systems is proposed, by mapping a high-dimensional system on a low-dimensional energy landscape. The DRL approach is applied to three biological networks, which validates that new reduced dimensions preserve the major information of stability and transition of original high-dimensional systems. The consistency of barrier heights calculated from the low-dimensional landscape and transition actions calculated from the high-dimensional system further shows that the landscape after dimension reduction can quantify the global stability of the system. The epithelial-mesenchymal transition (EMT) and abnormal metabolism are two hallmarks of cancer. With the DRL approach, a quadrastable landscape for metabolism-EMT network is identified, including epithelial (E), abnormal metabolic (A), hybrid E/M (H), and mesenchymal (M) cell states. The quantified energy landscape and kinetic transition paths suggest that for the EMT process, the cells at E state need to first change their metabolism, then enter the M state. The work proposes a general framework for the dimension reduction of a stochastic dynamical system, and advances the mechanistic understanding of the underlying relationship between EMT and cellular metabolism.

KLF5 promotes HpSlyD induced gastric intestinal metaplasia by activating Wnt/β-catenin pathway

BACKGROUND

Krüppel like factor 5 (KLF5) and the Wnt/β-catenin pathway are hot topics in the research of tumorigenesis. Some studies have found that KLF5 is related to the differentiation and proliferation of intestinal epithelial cells, suggesting that KLF5 may be involved in the occurrence of intestinal metaplasia. However, there are few reports on the effect of KLF5 on intestinal metaplasia and the underlying molecular mechanism.

AIM

To explore the effect of KLF5 on gastric intestinal metaplasia (GIM) induced by Helicobacter pylori (H. pylori) and the underlying mechanism.

METHODS

The mRNA and protein expression of KLF5 and Wnt3a was detected by RT-PCR and Western blot, respectively. Gastric epithelial cell line GES1 was cultured in vitro and divided into a blank control group, HpSlyD group (200 ng/mL HpSlyD + negative sequence), KLF5 interference group (200 ng/mL HpSlyD + KLF5 siRNA), Wnt agonist group (200 ng/mL HpSlyD + KLF5 siRNA + lithium chloride), and Wnt agonist + KLF5 interference group. GES1 cell proliferation and apoptosis were determined by MTT assay and flow cytometry, respectively. RT-PCR was used to detect KLF5, Wnt3a, beta-catenin, wool protein 1 (VIL1), trefoil factor 2 (TFF2), and caudal homeobox factor 2 (CDX2) mRNA expression. The expression of VIL1, TFF2, and CDX2 proteins was detected by Western blot.

RESULTS

The expression of KLF5 and Wnt3a mRNA and protein in intestinal metaplasia was significantly higher than that in the normal gastric mucosa (P < 0.01). The cell proliferation rates in the HpSlyD group and interference control group were significantly higher than that of the blank control group, and the apoptosis rates were significantly lower than that of the blank control group (P < 0.05). The cell proliferation rate of the KLF5 interference group was significantly lower than that of the HpSlyD group, and the apoptosis rate was significantly higher than that of the HpSlyD group (P < 0.05). The mRNA and protein expression of VIL1, TFF2, and CDX2 in the HpSlyD group and interference control group was significantly higher than that of the blank control group (P < 0.05), while the mRNA and protein expression of VIL1, TFF2, and CDX2 in the KLF5 interference group were significantly lower than those of the HpSlyD group (P < 0.05). The expression of Wnt3a, β-catenin, and CDX2 mRNA in the KLF5 interference group was significantly lower than that of the HpSlyD group (P < 0.05). The expression of Wnt3a, β-catenin, and CDX2 mRNA in the Wnt agonist + KLF5 interference group was significantly higher than that of the KLF5 interference group (P < 0.05).

CONCLUSION

Interference of KLF5 expression can significantly inhibit HpSlyD induced gastric metaplasia. KLF5 may promote HpSlyD induced gastric metaplasia by activating the Wnt/β-catenin pathway, which provides a new target for clinical prevention of gastric cancer.

The role and mechanism of β-arrestin2 in signal transduction

β-arrestin2 is a ubiquitously expressed scaffold protein localized on the cytoplasm and plasma membrane. It was originally found to bind to GPCRs, uncoupling G proteins and receptors' binding and inhibiting the signal transduction of the GPCRs. Further investigations have revealed that β-arrestin2 not only mediates the desensitization of GPCRs but also serves as a multifunctional scaffold to mediate receptor internalization, kinase activation, and regulation of various signaling pathways, such as TLR4/NF-κB, MAPK, Wnt, TGF-β, and AMPK/mTOR pathways. β-arrestin2 regulates cell invasion, migration, autophagy, angiogenesis, and anti-inflammatory effects by regulating various signaling pathways, which play a vital role in many physiological and pathological processes. This paper reviews the structure and function of β-arrestin2, the regulation of β-arrestin2 based signaling pathways. The role and mechanism of β-arrestin2 signaling have been delineated in sufficient detail. The prospect of regulating the expression and activity of β-arrestin2 in multisystem diseases holds substantial therapeutic promise.

PDLIM2 prevents the malignant phenotype of hepatocellular carcinoma cells by negatively regulating β-catenin

Hepatocellular carcinoma (HCC) is one of the most common malignancies and leading causes of cancer-related deaths globally. Despite significant advances in therapy, the molecular mechanisms underlying HCC development and progression remain unclear. Here, we aimed to explore the potential role of PDLIM2 in the development and epithelial-mesenchymal transition (EMT) of HCC via a possible modulation of β-catenin. We first confirmed that PDLIM2 was downregulated in HCC tissues and cells and found lower PDLIM2 expression was associated with worse prognosis in HCC patients. Loss- and gain- of function experiments were performed to evaluate the roles of PDLIM2 and β-catenin in HCC cell proliferation, migration, invasion, EMT, and colony formation. EMT was determined based on the levels of E-cadherin, zonula occludens-1, N-cadherin, and vimentin expression. In vivo, the roles of PDLIM2 and β-catenin in HCC were investigated by using a nude mouse xenograft model. It should be noted that PDLIM2 led to the inhibition of β-catenin activity and its downstream gene expression. Importantly, ectopic PDLIM2 expression inhibited the proliferation, migration, invasion, and EMT of HCC cells by reducing β-catenin expression both in vitro and in vivo, thereby suppressing the occurrence and progression of HCC. Taken together, our results demonstrated that overexpressed PDLIM2 exerts a tumor-suppressive role in HCC by regulating β-catenin. This study suggests that the PDLIM2 may be a promising target for the treatment of HCC.

Remodeling of whole-body lipid metabolism and a diabetic-like phenotype caused by loss of CDK1 and hepatocyte division

Cell cycle progression and lipid metabolism are well-coordinated processes required for proper cell proliferation. In liver diseases that arise from dysregulated lipid metabolism, hepatocyte proliferation is diminished. To study the outcome of CDK1 loss and blocked hepatocyte proliferation on lipid metabolism and the consequent impact on whole-body physiology, we performed lipidomics, metabolomics, and RNA-seq analyses on a mouse model. We observed reduced triacylglycerides in liver of young mice, caused by oxidative stress that activated FOXO1 to promote the expression of Pnpla2/ATGL. Additionally, we discovered that hepatocytes displayed malfunctioning β-oxidation, reflected by increased acylcarnitines (ACs) and reduced β-hydroxybutyrate. This led to elevated plasma free fatty acids (FFAs), which were transported to the adipose tissue for storage and triggered greater insulin secretion. Upon aging, chronic hyperinsulinemia resulted in insulin resistance and hepatic steatosis through activation of LXR. Here, we demonstrate that loss of hepatocyte proliferation is not only an outcome but also possibly a causative factor for liver pathology.

New Actors Driving the Epithelial-Mesenchymal Transition in Cancer: The Role of Leptin

Leptin is a hormone secreted mainly by adipocytes; physiologically, it participates in the control of appetite and energy expenditure. However, it has also been linked to tumor progression in different epithelial cancers. In this review, we describe the effect of leptin on epithelial-mesenchymal transition (EMT) markers in different study models, including in vitro, in vivo, and patient studies and in various types of cancer, including breast, prostate, lung, and ovarian cancer. The different studies report that leptin promotes the expression of mesenchymal markers and a decrease in epithelial markers, in addition to promoting EMT-related processes such as cell migration and invasion and poor prognosis in patients with cancer. Finally, we report that leptin has the greatest biological relevance in EMT and tumor progression in breast, lung, prostate, esophageal, and ovarian cancer. This relationship could be due to the key role played by the enriched tumor microenvironment in adipose tissue. Together, these findings demonstrate that leptin is a key biomolecule that drives EMT and metastasis in cancer.

Prognostic and Predictive Value of a 15 Transcription Factors (TFs) Panel for Hepatocellular Carcinoma

Purpose

Hepatocellular carcinoma (HCC) is one of the most devastating diseases worldwide. Limited performance of clinicopathologic parameters as prognostic factors underscores more accurate and effective biomarkers for high-confidence prognosis that guide decision-making for optimal treatment of HCC. The aim of the present study was to establish a novel panel to improve prognosis prediction of HCC patients, with a particular interest in transcription factors (TFs).

Materials and Methods

A TF-related prognosis model of liver cancer with data from ICGC-LIRP-JI cohort successively were processed by univariate and multivariate Cox regression analysis. Then, for evaluating the prognostic prediction value of the model, receiver operating characteristic (ROC) curve and survival analysis were performed both with internal data from the International Cancer Genome Consortium (ICGC) and external data from The Cancer Genome Atlas (TCGA). Furthermore, we verified the expression of three genes in HCC cell lines by Western blot and qPCR and protein expression level by IHC in liver cancer patients’ sample. Finally, we constructed a TF clinical characteristics nomogram to furtherly predict liver cancer patient survival probability with TCGA cohort.

Results

By Cox regression analysis, a panel of 15 TFs (ZNF331, MYCN, AHRR, LEF1, ZNF780A, POU1F1, DLX5, ZNF775, PLSCR1, FOXK1, TAL2, ZNF558, SOX9, TCFL5, GSC) was identified to present with powerful predictive performance for overall survival of HCC patients based on internal ICGC cohort and external TCGA cohort. A nomogram that integrates these factors was established, allowing efficient prediction of survival probabilities and displaying higher clinical utility.

Conclusion

The 15-TF panel is an independent prognostic factor for HCC, and 15 TF-based nomogram might provide implication an effective approach for HCC patient management and treatment.

Signaling pathways promoting epithelial mesenchymal transition in oral submucous fibrosis and oral squamous cell carcinoma

Epithelial-mesenchymal transition (EMT) is a critical process that occurs during the embryonic development, wound healing, organ fibrosis and the onset of malignancy. Emerging evidence suggests that the EMT is involved in the invasion and metastasis of cancers. The inflammatory reaction antecedent to fibrosis in the onset of oral submucous fibrosis (OSF) and the role of EMT in its malignant transformation indicates a hitherto unexplored involvement of EMT. This review focuses on the role of EMT markers which are regulators of the EMT mediated complex network of molecular mechanisms involved in the pathogenesis of OSF and OSCC. Further the gene enrichment analysis and pathway analysis supports the association of the upregulated and downregulated genes in various EMT regulating pathways.

Mesenchymal to epithelial transition driven by canine distemper virus infection of canine histiocytic sarcoma cells contributes to a reduced cell motility in vitro

Sarcomas especially of histiocytic origin often possess a poor prognosis and response to conventional therapies. Interestingly, tumours undergoing mesenchymal to epithelial transition (MET) are often associated with a favourable clinical outcome. This process is characterized by an increased expression of epithelial markers leading to a decreased invasion and metastatic rate. Based on the failure of conventional therapies, viral oncolysis might represent a promising alternative with canine distemper virus (CDV) as a possible candidate. This study hypothesizes that a CDV infection of canine histiocytic sarcoma cells (DH82 cells) triggers the MET process leading to a decreased cellular motility. Immunofluorescence and immunoblotting were used to investigate the expression of epithelial and mesenchymal markers followed by scratch assay and an invasion assay as functional confirmation. Furthermore, microarray data were analysed for genes associated with the MET process, invasion and angiogenesis. CDV‐infected cells exhibited an increased expression of epithelial markers such as E‐cadherin and cytokeratin 8 compared to controls, indicating a MET process. This was accompanied by a reduced cell motility and invasiveness. Summarized, these results suggest that CDV infection of DH82 cells triggers the MET process by an increased expression of epithelial markers resulting in a decreased cell motility in vitro.

A three-gene signature might predict prognosis in patients with acute myeloid leukemia

The identification of effective signatures is crucial to predict the prognosis of acute myeloid leukemia (AML). The investigation aimed to identify a new signature for AML prognostic prediction by using the three-gene expression (octamer-binding transcription factor 4 (OCT4), POU domain type 5 transcription factor 1B (POU5F1B) and B-cell-specific Moloney murine leukemia virus integration site-1 pseudogene 1 (BMI1P1). The expressions of genes were obtained from our previous study. Only the specimens in which three genes were all expressed were included in this research. A three-gene signature was constructed by the multivariate Cox regression analyses to divide patients into high-risk and low-risk groups. Receiver operating characteristic (ROC) analysis of the three-gene signature (area under ROC curve (AUC) = 0.901, 95% CI: 0.821–0.981, P<0.001) indicated that it was a more valuable signature for distinguishing between patients and controls than any of the three genes. Moreover, white blood cells (WBCs, P=0.004), platelets (PLTs, P=0.017), percentage of blasts in bone marrow (BM) (P=0.011) and complete remission (CR, P=0.027) had significant differences between two groups. Furthermore, high-risk group had shorter leukemia-free survival (LFS) and overall survival (OS) than low-risk group (P=0.026; P=0.006), and the three-gene signature was a prognostic factor. Our three-gene signature for prognosis prediction in AML may serve as a prognostic biomarker.

Cellular Functions of OCT-3/4 Regulated by Ubiquitination in Proliferating Cells

Octamer-binding transcription factor 3/4 (OCT-3/4), which is involved in the tumorigenesis of somatic cancers, has diverse functions during cancer development. Overexpression of OCT-3/4 has been detected in various human somatic tumors, indicating that OCT-3/4 activation may contribute to the development and progression of cancers. Stem cells can undergo self-renewal, pluripotency, and reprogramming with the help of at least four transcription factors, OCT-3/4, SRY box-containing gene 2 (SOX2), Krüppel-like factor 4 (KLF4), and c-MYC. Of these, OCT-3/4 plays a critical role in maintenance of undifferentiated state of embryonic stem cells (ESCs) and in production of induced pluripotent stem cells (iPSCs). Stem cells can undergo partitioning through mitosis and separate into specific cell types, three embryonic germ layers: the endoderm, the mesoderm, and the trophectoderm. It has been demonstrated that the stability of OCT-3/4 is mediated by the ubiquitin-proteasome system (UPS), which is one of the key cellular mechanisms for cellular homeostasis. The framework of the mechanism is simple, but the proteolytic machinery is complicated. Ubiquitination promotes protein degradation, and ubiquitination of OCT-3/4 leads to regulation of cellular proliferation and differentiation. Therefore, it is expected that OCT-3/4 may play a key role in proliferation and differentiation of proliferating cells.

OCT4B1 Promoted EMT and Regulated the Self-Renewal of CSCs in CRC: Effects Associated with the Balance of miR-8064/PLK1

Cancer stem cells (CSCs) are the main cause of tumor generation, recurrence, metastasis, and therapy failure in various malignancies including colorectal cancer (CRC). Accumulating evidence suggests that tumor cells can acquire CSC characteristics through the epithelial-mesenchymal transition (EMT) process. However, the molecular mechanism of CSCs remains unclear. OCT4B1 is a transcript of OCT4, which is initially expressed in embryonic stem and carcinoma cells, and is involved in the regulation and maintenance of an undifferentiated state of stem cells. In this study, three-dimensional (3D) microspheres were confirmed as CRC stem cells. Compared with that of parental cells, their self-renewal ability was significantly increased, and OCT4B1 expression was increased and promoted the EMT process. The knockdown of OCT4B1 decreased the self-renewal of CSCs and reversed EMT. Moreover, OCT4B1 induced the expression of Polo-like kinase 1 (PLK1), which is a key regulator of EMT in tumor cells. Further examination showed that OCT4B1 regulated the miR-8064/PLK1 balance to exert its function. Taken together, our data suggest that OCT4B1 may be involved in regulating the self-renewal of colorectal CSCs through EMT, which is at least partially due to the miR-8064/PLK1 balance. This study indicates that OCT4B1 is a potential therapeutic target for CRC by targeting CSCs.

The transcription factor LEF1 promotes tumorigenicity and activates the TGF-β signaling pathway in esophageal squamous cell carcinoma

Background

Esophageal squamous cell carcinoma (ESCC) is the most difficult subtype of esophageal cancer to treat due to the paucity of effective targeted therapy. ESCC is believed to arise from cancer stem cells (CSCs) that contribute to metastasis and chemoresistance. Despite advances in diagnosis and treatment, the prognosis of ESCC patients remains poor.

Methods

In this study, we applied western blot, quantitative real-time polymerase chain reaction (qRT-PCR), immunohistochemistry, RNA-Seq analysis, luciferase reporter assay, Chip-qPCR, bioinformatics analysis, and a series of functional assays to show the potential role of LEF1 in regulating esophageal CSCs.

Results

We found that the overexpression of LEF1 was associated with aberrant clinicopathological characteristics and the poor prognosis of ESCC patients. In addition, the elevated expression of LEF1 and OV6 was significantly associated with aberrant clinicopathological features, and poor patient prognosis. Moreover, the overexpression of LEF1 was observed in esophageal CSCs purified by the magnetic sorting of adherent and spheroidal ESCC cells. The increased level of LEF1 in CSCs facilitated the expression of CSC markers, stem cell-like properties, resistance to chemotherapy, and tumorigenicity and increased the percentage of CSCs in ESCC samples. Conversely, the knockdown of LEF1 significantly diminished the self-renewal properties of ESCC. We showed that LEF1 played an important mechanical role in activating the TGF-β signaling pathway by directly binding to the ID1 gene promoter. A positive association between LEF1 and ID1 expression was also observed in clinical ESCC samples.

Conclusion

Our results indicate that the overexpression of LEF1 promotes a CSC-like phenotype in and the tumorigenicity of ESCC by activating the TGF-β signaling pathway. The inhibition of LEF1 might therefore be a novel therapeutic target to inactivate CSCs and inhibit tumor progression.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1296-7) contains supplementary material, which is available to authorized users.

DUXAP10 inhibition attenuates the proliferation and metastasis of hepatocellular carcinoma cells by regulation of the Wnt/β-catenin and PI3K/Akt signaling pathways

The long non-coding RNA DUXAP10 has been involved in the development, progression, and metastasis in several human cancers, but its biological function and underlying mechanism in hepatocellular carcinoma (HCC) still undetermined. The present study was proposed to explore the effect of DUXAP10 on the growth and metastasis of HCC cells and the potential mechanisms involved. The results showed that DUXAP10 is dramatically elevated in HCC tumor tissues and cell lines. Knockdown of DUXAP10 by DUXAP10 si-RNA significantly inhibited the cell viability, proliferation and induce the apoptosis of HCC cell line. Meanwhile, inhibition of DUXAP10 attenuates the cell migration, invasion, and epithelial-mesenchymal transition (EMT) process. No significant change of JNK MAPK pathway was detected in DUXAP10 siRNA transfected HCC cell lines. The β-catenin and pAkt levels were decreased in the Hep G2+DUXAP10 siRNA and SMMC7721+DUXAP10 siRNA groups, while the activation of Wnt/β-catenin or PI₃K/Akt suppressed the inhibition of DUXAP10 siRNA on cell proliferation and migration. Collectively, DUXAP10 plays a critical role in regulating HCC development, potentially by regulating EMT and cell proliferation through the PI₃K/Akt and Wnt/β-catenin signaling. Inhibition of DUXAP10 in HCC HepG2 cells could attenuate the EMT and cell proliferation and invasion. Therefore, DUXAP10 might be a promising therapy target to inhibit the growth of HCC.

Octamer binding transcription factor-4 expression is associated with cervical cancer malignancy and histological differentiation: a systematic review and meta-analysis

Objective: In this work, the relationship between octamer binding transcription factor 4 (OCT-4) expression and the clinicopathological features of cervical cancer (CC) is evaluated in detail.

Methods: The library databases Pubmed, Embase, Cochrane library, Wan Fang and Chinese National Knowledge Infrastructure (CNKI) were searched for research related to these concepts published from the time the databases were established until May 2018. The obtained studies are screened, extracted, and evaluated according to the inclusion and exclusion criteria, and meta-analysis is carried out via RevMan 5.3.

Results: Ten case–control studies, including 408 cases of CC, 164 cases of cervical intraepithelial neoplasia (CIN), and 148 cases of normal cervix, are included in the analysis. Results show that OCT-4 levels are statistically significantly different between the CC and normal cervical tissue groups (odds ratio (OR) = 15.59, 95% confidence interval (CI): 8.70, 27.94), the CC and CIN groups (OR = 5.64, 95% CI: 3.23, 9.86), the CIN and normal cervical tissues groups (OR = 7.13, 95% CI: 2.41, 21.05), and the CC well/moderately differentiated and poorly differentiated groups (OR = 0.44, 95% CI: 0.24, 0.81). OCT-4 is not statistically significantly different between CIN I + II and CIN III tissues (OR = 0.40, 95% CI: −0.02, 0.81), the CC lymphatic and non-lymphatic metastasis groups (OR = 1.93, 95% CI: 0.83, 4.47), the FIGO I and FIGO II groups (OR = 0.79, 95% CI: 0.29, 2.13), and the adenocarcinoma and squamous cell carcinoma groups (OR = 1.55, 95% CI: 0.70, 3.44).

Conclusions: The available evidence suggests that OCT-4 expression is associated with CC malignancy and histological differentiation. This finding, however, is subject to quantitative studies and quality tests.

Apoptotic protease activating factor-1 negatively regulates Wnt signaling in hepatocellular carcinoma

The current study aims to evaluate the mechanism of apoptotic protease activating factor-1 (Apaf-1) in hepatocellular carcinoma (HCC) cells by verifying the regulation of the wnt/beta-catenin signaling pathway via Apal-1. Our data showed that transfection with Ad-Apaf-1 could inhibit the activity of a lymphoid enhancer factor (LEF) luciferase plasmid activated by β-catenin. Overexpressing Apaf-1 could suppress the β-catenin-induced LEF luciferase activity in a dose-dependent manner. Western blot assays demonstrated that the overexpression of Apaf1 significantly suppressed the expression of Wnt/β-catenin signaling-related proteins. Further study demonstrated that Apaf-1 suppressed HepG2 cell migration, invasion, and viability. Knocking down the expression of Apaf-1 activated the wnt/β-catenin pathway in HepG2 cells. In contrast, silencing β-catenin decreased the activation of wnt/β-catenin, even in the presence of si-Apaf-1. Cell cycle distribution analysis demonstrated a decrease in the number of cells in the G0/G1 phase in the Apaf-1 silencing group. In contrast, knocking down the expression of β-catenin increased the number of cells in the G0/G1 phase, even in the presence of si-Apaf-1. In summary, the Apaf-1-mediated suppression of HepG2 cell malignancy is achieved by inhibiting the wnt/β-catenin pathway.

ZSCAN10 promotes cell proliferation, upregulates OCT4 expression, and activates Wnt/β-catenin signaling in glioma

Glioma is the most common malignant brain tumor. The dominant therapeutics including surgery, radiotherapy and chemotherapy do little to improve the survival of patients and the prognosis is disappointing. ZSCAN10 is critical in maintaining the pluripotency of embryonic stem cells. Little information was known about its function in glioma. In this study, ZSCAN10 was shown to be expressed significantly higher in glioma tissues and in cell lines. High ZSCAN10 expression was associated with poor prognosis in glioma. When ZSCAN10 was knocked down, proliferation as well as colony formation of glioma cells were inhibited drastically. In contrast, overexpression of ZSCAN10 promoted cell proliferation and colony formation. However, apoptosis was not affected by ZSCAN10. ZSCAN10 was shown to enhance expression of OCT4 through interaction with the promoter of OCT4 gene by ChIP-qPCR assay and luciferase reporter assay. ZSCAN10 could not promote proliferation of U251 cells when OCT4 was knocked down. In addition, the expression of β-catenin was down-regulated after ZSCAN10 knockdown in U251 cells However, the expression level of DKK1 increased inversely. In summary, ZSCAN10 was associated with survival of glioma patients and contributed to cell proliferation through upregulating OCT4 expression. Moreover, ZSCAN10 might partially participate in the activation of Wnt/β-catenin signaling in glioma.

miR‑300 regulates tumor proliferation and metastasis by targeting lymphoid enhancer‑binding factor 1 in hepatocellular carcinoma

Accumulating evidence indicates that microRNAs (miRNAs) have a critical role in cell proliferation and metastasis in hepatocellular carcinoma (HCC). However, the effect of miR-300 on the development and progression of HCC remains unclear. In the present study, it was observed that miRNA (miR)-300 expression was significantly decreased in HCC cell lines compared with normal liver cells. Furthermore, we detected the effects of miR-300 on cell proliferation and apoptosis, cell cycle, migration and invasion by using MTT, colony formation assay, wound healing, Transwell assay and flow cytometry methods, respectively. The results demonstrated that miR-300 overexpression inhibited proliferation, induced apoptosis and G1/S cell cycle arrest, and suppressed migration and invasion in Huh-7 cells, whereas miR-300 silencing promoted the proliferation, migration and invasion of Hep3B cells. Mechanistically, the transcription factor lymphoid enhancer-binding factor 1 (LEF-1), which was verified as a direct target gene of miR-300, promoted cell proliferation, migration and invasion and mediates the effects of miR-300 on HCC cells. In addition, low expression of miR-300 and high expression of LEF-1 in HCC tissues were found to be associated with poor prognosis of patients with HCC. These findings indicate that miR-300 may be a potential prognostic predictor and therapeutic target for patients with HCC.

SOX2 knockdown inhibits the migration and invasion of basal cell carcinoma cells by targeting the SRPK1-mediated PI3K/AKT signaling pathway

Basal cell carcinoma (BCC) is the most common type of human skin cancer, which is driven by the aberrant activation of Hedgehog signaling. Previous evidence indicated that sex determining region Y-box 2 (SOX2) is associated with the tumor metastasis. However, the expression and role of SOX2 in BCC remain unknown. Therefore, the aim of the current study was to analyze the possible mechanism of SOX2 in the progression of BCC. The levels of SOX2 in BCC cells were detected by reverse transcription-quantitative polymerase chain reaction. Transwell assays were also used to determine the migration and invasion of BCC cells. Immunoblotting and immunofluorescence were used for analyzing the role of SOX2 knockdown in the serine-arginine protein kinase 1 (SRPK1)-mediated phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) signaling pathway in BCC cells. The results demonstrated that SOX2 is overexpressed in BCC tissues and cells. In addition, SOX2 knockdown inhibited the migration and invasion of BCC cells, and the epithelial-mesenchymal transition (EMT) progress of BCC cells. It was also observed that SOX2 knockdown decreased SRPK1 expression, which further led to the downregulation of PI3K and AKT expression levels in BCC cells. Furthermore, SRPK1 transfection or PI3K/AKT pathway activation abolished the inhibitory effects of SOX2 knockdown on the migration, invasion and EMT progress of BCC cells. In conclusion, these results indicated that SOX2 may potentially serve as a target for BCC therapy by targeting the SRPK1-mediated PI3K/AKT signaling pathway.

Lymphoid Enhancer Factor 1 Contributes to Hepatocellular Carcinoma Progression Through Transcriptional Regulation of Epithelial-Mesenchymal Transition Regulators and Stemness Genes

Lymphoid enhancer factor 1 (LEF1) activity is associated with progression of several types of cancers. The role of LEF1 in progression of hepatocellular carcinoma (HCC) remains poorly known. We investigated LEF1 expression in HCC and its interactions with epithelial-mesenchymal transition (EMT) regulators (e.g., Snail, Slug, Twist) and stemness genes (e.g., octamer-binding transcription factor 4 [Oct4], sex determining region Y-box 2 [Sox2], Nanog homeobox [Nanog]). Microarray analysis was performed on resected tumor samples from patients with HCC with or without postoperative recurrence. LEF1 expression was associated with postoperative recurrence as validated by immunohistochemical staining in another HCC cohort. Among 74 patients, 44 displayed a relatively high percentage of LEF1 staining (>30% of HCC cells), which was associated with a reduced recurrence-free interval (P < 0.001) and overall survival (P = 0.009). In multivariate analysis, a high percentage of LEF1 staining was significantly associated with low albumin level (P = 0.035), Twist overexpression (P = 0.018), Snail overexpression (P = 0.064), co-expression of Twist and Snail (P = 0.054), and multinodular tumors (P = 0.025). Down-regulation of LEF1 by short hairpin RNA decreased tumor sphere formation, soft agar colony formation, and transwell invasiveness of HCC cell lines Mahlavu and PLC. Xenotransplant and tail vein injection experiments revealed that LEF1 down-regulation in Mahlavu reduced tumor size and metastasis. LEF1 up-regulation in Huh7 increased sphere formation, soft agar colony formation, and transwell invasiveness. LEF1 was shown to physically interact with and transcriptionally activate promoter regions of Oct4, Snail, Slug, and Twist. Furthermore, Oct4, Snail, and Twist transactivated LEF1 to form a regulatory positive-feedback loop. Conclusion: LEF1 plays a pivotal role in HCC progression through transcriptional regulation of Oct4 and EMT regulators.

A Panel of Genes Identified as Targets for 8q24.13-24.3 Gain Contributing to Unfavorable Overall Survival in Patients with Hepatocellular Carcinoma

Copy number aberrations (CNAs) in chromosome arm 8q have been associated with unfavorable clinical outcomes of several cancers and progressive tumor characteristics of hepatocellular carcinoma (HCC). This study was to identify correlation of CNAs in 8q with clinical outcomes of HCC patients, and further screen for differentially expressed genes in outcome-related CNAs. Array comparative genomic hybridization and expression arrays were performed to detect CNAs and expression levels, respectively. The correlations between CNAs in 8q and outcomes were analyzed in 66 patients, with a median follow-up time of 45.0 months (range, 2.6-108.6 months). One hundred and nine cases were further evaluated to identify differentially expressed genes in the potential outcome-related CNAs. Copy number gain in 8q was observed in 22 (33.3%) of the 66 HCC cases. The most recurrent gains (with frequencies >20%) were 8q13.3-21.3,8q21.3-23.3,8q23.3-24.13,8q24.13-24.3, and 8q24.3. Survival analysis showed that 8q24.13-24.3 gain was significantly associated with reduced overall survival (jP=0.010). Multivariate Cox analysis identified 8q24.13-24.3 gain as an independent prognostic factor for poor overall survival (HR=2.47; 95% CI=1.16-5.26; Р=0.019). Apanel of 17 genes within the 8q24.13-24.3 region, including ATAD2,SQLE,PVT1,ASAP1, and NDRG1 were significantly upregulated in HCCs with 8q24.13-24.3 gain compared to those without. These results suggest that copy number gain at 8q24.13-24.3 is an unfavorable prognostic marker for HCC patients, and the potential oncogenes ATAD2,SQLE, PVT1, ASAP1,and NDRG1 within the regional gain, may contribute coordinately to the 8q24.13-24.3 gain-related poor prognosis.

OCT4 Potentiates Radio-Resistance and Migration Activity of Rectal Cancer Cells by Improving Epithelial-Mesenchymal Transition in a ZEB1 Dependent Manner

Radiotherapy is an important strategy for rectal cancer patient treatment. However, the efficiency of radiation is usually poor, especially in patients with advanced stage rectal cancer due to the radio-resistance developed. At the present study, OCT4 was found to play a critical role in radio-resistance development in human rectal cancer cells by improving the epithelial-mesenchymal transition process (EMT). Endogenous OCT4 expression could confer resistant phonotype on human rectal cancer cells, which was supported by the data from clonogenic forming assay and cell cycle arrest recovering experiment. EMT related transcription factor ZEB1 might take part in the radio-resistance induced by OCT4, as its expression could be upregulated by OCT4 and its silence could reverse the OCT4 induced resistance to radiation in SW480 cells. More interestingly, CHK1 was also upregulated in OCT4/ZEB1 dependent manner conferring stronger DNA damage repair activity on cancer cells, which might explain the underlying mechanisms why OCT4/ZEB1 axis could promote the resistance of human rectal cancer cell to radiation. Taken together, our results provided a novel mechanism for radio-resistance development in human rectal cancer cells and a new target to overcome this resistance.

Prognostic value of association of OCT4 with LEF1 expression in esophageal squamous cell carcinoma and their impact on epithelial-mesenchymal transition, invasion, and migration

Esophageal squamous cell carcinoma (ESCC) is a malignant disease with poor prognosis. Because of early metastasis prior to diagnosis and therapeutic resistance, ESCC has become one of the leading causes of cancer-related death. Here, we investigated the clinicopathological significance of the association of octamer-binding transcription factor 4 (OCT4) with lymphoid enhancer-binding factor 1 (LEF1) expression and the potential molecular mechanism in the epithelial-mesenchymal transition (EMT), invasion, and migration of ESCC. The expression of OCT4 and LEF1 was detected via immunohistochemistry analysis. High levels of LEF1 expression were observed in 95 ESCC specimens and were obviously associated with aberrant clinicopathological features and poor patient prognosis. Our previous study showed that OCT4 expression level is elevated in ESCC, and statistical analysis showed that the elevated expression of OCT4 and LEF1 in ESCC was significantly associated with histologic grade, lymph node metastasis, TNM stage, and poor patient prognosis. The specific inhibition of OCT4 expression via a lentivirus encoding OCT4-shRNA (LV-shOCT4) in Eca109 cells led to decreased levels of OCT4 and LEF1 in vitro. Additionally, we applied a rescue strategy by infecting LV-shOCT4 Eca109 cells with a LEF1 overexpression plasmid (p-LEF1) and detected changes in EMT, migration, and invasion. Unsurprisingly, the p-LEF1 group exhibited greater EMT, invasion, and migration than did the LV-shOCT4 and negative control groups. This study demonstrates for the first time the relationship between OCT4 and LEF1 expression. The combination of high expression of OCT4 and LEF1 was associated with clinicopathological features of atypical patients, and this combination might be an ideal prognostic factor in ESCC. OCT4 positively regulated LEF1 expression, and LEF1 mediated the effects of OCT4 in cancer cell EMT, invasion, and migration. The data presented here suggest that the inhibition of OCT4-LEF1 signaling may be a new therapeutic target for the treatment of ESCC.

Role of p38 MAPK in disease relapse and therapeutic resistance by maintenance of cancer stem cells in head and neck squamous cell carcinoma

AIM

This study aimed to investigate the role of p38 MAPK in maintenance of cancer stem cell (CSC) phenotype, therapy resistance, and DNA damage repair and response in head and neck squamous cell carcinoma (HNSCC).

METHODS

In this study, 104 HNSCC patients were included. Western blot, immunohistochemistry, and qPCR analysis were performed to investigate the expression level of p-p38 and CSC markers in cut margin and tumor area of HNSCC patients. The expression level of p-p38 and CSC markers was also evaluated in HNSCC cells with or without p38 inhibitor. Chemoresistance, wound healing capacity, and multicellular tumor spheroids (MCTS) formation capacity were evaluated in HNSCC-derived cell lines with or without p38 inhibitor. In addition, DNA damage response and repair capacities were also evaluated in HNSCC cells after p38 inhibition using alkaline comet assay and γ-H₂ AX immunostaining.

RESULT

We observed that recurrence could be associated with upregulated status of p-p38 and p38α gene in cut margin area of HNSCC patients as compared to tumor region. p38-inhibited cells showed significantly reduced expression of CSC markers, chemosensitivity toward cisplatin, reduced migration potential, and sphere-forming ability along with increased apoptotic population after treatment with increasing concentration of cisplatin. p38-inhibited cells also exhibited significantly increased comet olive tail moment and accumulation of γ-H₂ AX, demonstrating increased DNA damage.

CONCLUSION

This study demonstrated that p38 MAPK activation may play a role in therapeutic resistance and disease relapse in HNSCC by maintenance of CSCs phenotype.

MicroRNA-671-3p inhibits the development of breast cancer: A study based on in vitro experiments, in-house quantitative polymerase chain reaction and bioinformatics analysis

MicroRNAs (miRNAs or miRs) are highly conserved small noncoding RNA molecules involved in gene regulation. An increasing number of studies have demonstrated that miRNAs act as oncogenes or antioncogenes in various types of cancer, including breast cancer (BC). However, the exact role of miR‑671‑3p in BC has not yet been reported. In the present study, in vitro experiments were implemented to explore the effects of miR‑671‑3p on the proliferation and apoptosis of BC cells, and reverse transcription‑quantitative polymerase chain reaction was conducted using in‑house clinical BC samples to address the expression level and clinical value of miR‑671‑3p in BC. Simultaneously, miR‑671‑3p target genes were collected, and subsequent bioinformatics analyses were executed to probe the potential signaling pathway through which miR‑671‑3p influenced the occurrence and progression of BC. According to the results, the expression level of miR‑671‑3p was lower in BC tissues compared with that in adjacent non‑tumorous tissues (P=0.048), and the area under the curve was 0.697 (95% confidence interval=0.538‑0.856), with a sensitivity and specificity of 0.818 and 0.579, respectively. Forced miR‑671‑3p expression in the BC cell line MDA‑MB‑231 evidently arrested cell proliferation and induced cell apoptosis. Furthermore, in silico enrichment analyses suggested that miR‑671‑3p may be involved in the initiation and progression of BC through the targeting of genes associated with the Wnt signaling pathway. In conclusion, the present study findings suggested that miR‑671‑3p may function as a tumor suppressor in BC by influencing the Wnt signaling cascade, which provides a prospective molecular target for the therapy of BC.

NEAT1 acts as an inducer of cancer stem cell-like phenotypes in NSCLC by inhibiting EGCG-upregulated CTR1

Long non-coding RNAs (lncRNAs) play significant roles in the pathogenesis of various cancers, including lung cancer. In this study, we aimed to investigate the biological function of lncRNA nuclear enriched abundant transcript 1 (NEAT1) in cancer stem cells (CSCs). CSCs have been suggested as the main cause of tumor metastasis, tumor recurrence, and chemotherapy resistance. The copper transporter 1 (CTR1) has been the focus of many recent studies because of its correlation with cisplatin (CDDP) resistance. So far, the mechanism of how NEAT1 regulates CSCs in NSCLC remains unknown. In the current study, lung cancer stem cells were enriched from the parental NSCLC cells. We observed that NEAT1 was up-regulated while copper transporter 1 (CTR1) was down-regulated in the enriched NSCLC cancer stem cells. Knockdown of NEAT1 was able to decrease the CSC-like properties in NSCLC cells, while over-expression of NEAT1 could contribute to the stemness respectively. Meanwhile, appropriate doses of EGCG restrained the stemness triggered by over-expressing NEAT1 via inducing CTR1 expression. Wnt signal pathway and epithelial-to-mesenchymal transition (EMT) process were involved in NEAT1-induced CSCs in NSCLC. These findings may suggest a novel role of NEAT1 for NSCLC treatment.

The role and mechanism of β‑arrestins in cancer invasion and metastasis (Review)

β-arrestins are a family of adaptor proteins that regulate the signaling and trafficking of various G protein-coupled receptors (GPCRs). They consist of β-arrestin1 and β-arrestin2 and are considered to be scaffolding proteins. β-arrestins regulate cell proliferation, promote cell invasion and migration, transmit anti-apoptotic survival signals and affect other characteristics of tumors, including tumor growth rate, angiogenesis, drug resistance, invasion and metastatic potential. It has been demonstrated that β-arrestins serve roles in various physiological and pathological processes and exhibit a similar function to GPCRs. β-arrestins serve primary roles in cancer invasion and metastasis via various signaling pathways. The present review assessed the function and mechanism of β-arrestins in cancer invasion and metastasis via multiple signaling pathways, including mitogen-activated protein kinase/extracellular signal regulated kinase, Wnt/β-catenin, nuclear factor-κB and phosphoinositide-3 kinase/Akt.

Effects of microRNA-708 on Epithelial-Mesenchymal Transition, Cell Proliferation and Apoptosis in Melanoma Cells by Targeting LEF1 through the Wnt Signaling Pathway

This study was conducted in order to elucidate the role microRNA-708 (miR-708) plays between proliferation, invasion, migration, and epithelial-mesenchymal transition (EMT) involving melanoma cells by targeting using LEF1 through the Wnt signaling pathway. Male Kunming mice were selected and subsequently divided into normal and model groups to take part in this study. Following cell line selection, the B16 cells with the highest miR-708 expression were selected and assigned into the control, blank, negative control (NC), miR-708 mimic, miR-708 inhibitor, siRNA-LEF1, and miR-708 inhibitor + siRNA-LEF1 groups. A Bioinformatics Web service and dual-luciferase reporter assay were conducted in order to determine the relationship between LEF1 and miR-708. The RT-qPCR method was performed in order to detect the miR-708 expression and mRNA expressions of LEF1, β-catenin, Wnt3a, N-cadherin, Bcl-2, Bax, Caspase3, E-cadherin, and western blotting was used in order to detect the protein expressions of these genes. MTT assay, scratch test, Transwell assay, and flow cytometry were all conducted in order to detect the cell proliferation, migration, invasion, and cycle/apoptosis, respectively. LEF1 was verified as the target gene of miR-708. In comparison with the normal group, the model group had reduced expressions of miR-708, Bax, Caspase3, and E-cadherin, while showing elevated expressions of LEF1, β-catenin, Bcl-2, Wnt3a, and N-cadherin. In comparison to the blank and control groups, the miR-708, mimic, and siRNA-LEF1 groups had elevated expressions of Bax, Caspase3, and E-cadherin, while also showing enhanced cell apoptosis. The miR-708, mimic, and siRNA-LEF1 groups also had decreased expressions of LEF1, β-catenin, Bcl-2, Wnt3a, and N-cadherin, and reduced optical density value 48 h and 72 h after transfection. Besides, these two groups showed declined cell migration and invasion, as well as lengthened G0/G1 phase (increased cell number) and shortened S phase (decreased cell number). Our findings demonstrated that an overexpressed miR-708 inhibits the proliferation, invasion, migration, and EMT, but also promotes the apoptosis of melanoma cells by targeting LEF1 through the suppression of the Wnt signaling pathway.

Progress and prospects of circular RNAs in Hepatocellular carcinoma: Novel insights into their function

Hepatocellular carcinoma (HCC) is one of the most predominant subjects of liver malignancies, which arouses global concern in the recent years. Advanced studies have found that Circular RNAs (circRNAs) are differentially expressed in HCC, with its regulatory capacity in HCC pathogenesis and metastasis. However, the underlying mechanism remains largely unknown. In this review, we summarized the functions and mechanisms of those aberrantly expressed circRNAs in HCC tissues. We hope to enlighten more comprehensive studies on the detailed mechanisms of circRNAs and explore their potential values in clinic applications. It revealed that hsa_circ_0004018 can be used as a potential biomarker in HCC diagnosis, with its superior sensitivity to alpha-fetoprotein (AFP). Notably, the correlation of circRNA abundance in the proliferation of liver regeneration (LR) has recently been clarified and different circRNA profiles served as candidates for nonalcoholic steatohepatitis (NASH) diagnosis also be discussed. Therefore, the improved understanding of circRNAs in HCC pathogenesis and metastasis proposed a novel basis for the early diagnosis in HCC patients, which provides a useful resource to explore the pathogenesis of HCC.