Epithelial-mesenchymal transition is regulated at post-transcriptional levels by transforming growth factor-β signaling during tumor progression

Sarcomatoid carcinoma of the pancreas (Review)

Sarcomatoid carcinoma of the pancreas (SCP) is a rare and aggressive subtype of undifferentiated pancreatic ductal adenocarcinoma, with a generally poor prognosis and only sporadic cases reported worldwide. Histologically, the most notable feature of SCP is the presence of abundant of mesenchymatoid spindle tumor cells in the tumor, which lack glandular differentiation. Immunohistochemically, SCP is characterized by the expression of both mesenchymal and epithelial markers. With only a few reported cases, there is limited knowledge about its molecular and clinicopathological characteristics. Therefore, the present study performed a literature search to identify all relevant published studies. The present review provides an overview of the histogenesis, diagnosis, genetic features, prognosis and treatment of SCP, specifically focusing on the molecular alterations. Furthermore, a single-center experience is reported, which adds to the limited evidence available in the literature.

Metabolic landscaping of extracellular vesicles from body fluids by phosphatidylserine imprinted polymer enrichment and mass spectrometry analysis

Extracellular vesicles (EVs) are emerging as new source of biomarkers discovery in liquid biopsy due to their stabilization in body fluids, protected by phospholipid bilayers. However, the metabolomics study of EVs is very little reported due to the lack of efficient and high-throughput isolation methods for clinical samples. In this study, phosphatidylserine imprinted polymers were employed for rapid and efficient EVs isolation from five human body fluids, including plasma, urine, amniotic fluid, cerebrospinal fluid, and saliva. The isolated EVs were subsequently analyzed for metabolomic studies by high-resolution mass spectrometry. Metabolic landscaping was conducted between the body fluids and their EVs, indicating EVs contain a large number of metabolites that are completely specific to the body fluid source. Finally, quantitative metabolomic analysis of EVs was carried out with plasma samples of hepatocellular carcinoma. Several differentially expressed exosomal metabolites were revealed including the upregulation of sphingosine (d18:1), taurochenodeoxycholic acid (TCDCA), pipecolic acid (PA), and 4-hydroxynonenal (4-HNE) and down-regulation of piperine, caffeine, and indole. We believe the proposed methodology will provide a deeper understanding of the molecular composition and functions of EVs as an alternative source for biomarker discovery.

Factors Determining Epithelial-Mesenchymal Transition in Cancer Progression

Epithelial-mesenchymal transition (EMT) is a process in which an epithelial cell undergoes multiple modifications, acquiring both morphological and functional characteristics of a mesenchymal cell. This dynamic process is initiated by various inducing signals that activate numerous signaling pathways, leading to the stimulation of transcription factors. EMT plays a significant role in cancer progression, such as metastasis and tumor heterogeneity, as well as in drug resistance. In this article, we studied molecular mechanisms, epigenetic regulation, and cellular plasticity of EMT, as well as microenvironmental factors influencing this process. We included both in vivo and in vitro models in EMT investigation and clinical implications of EMT, such as the use of EMT in curing oncological patients and targeting its use in therapies. Additionally, this review concludes with future directions and challenges in the wide field of EMT.

MiR-338-5p, a novel metastasis-related miRNA, inhibits triple-negative breast cancer progression by targeting the ETS1/NOTCH1 axis

Breast cancer ranks as the most prevalent cancer globally, surpassing lung cancer, with recurrence/metastasis to be its main account for the cancer-related mortality. MicroRNAs (miRNAs) participate critically in various physiological and pathological processes through posttranscriptional regulation of downstream genes. Our preliminary findings identified miR-338-5p, potentially linked to metastasis in breast cancer, a previously unexplored area. Analysis of the GSE38867 dataset revealed the decreased miR-338-5p expression in metastatic breast cancer compared to normal tissues. Cellular function experiments and a xenograft tumor model demonstrated the inhibitory function of miR-338-5p on the progression of breast cancer in vitro and in vivo. Furthermore, it downregulated the expression of mesenchymal biomarkers and NOTCH1 significantly. With the predicting targets of miR-338-5p and transcription factors of the NOTCH1 gene, coupled with dual luciferase reporter assays, it is identified ETS1 as the interactor between miR-338-5p and NOTCH1. In breast cancer tissues, as well as in our xenograft tumor model, expression of ETS1 and NOTCH1 was positively correlated using immunohistochemical staining. This study reports, for the first time, on the miR-338-5p/ETS1/NOTCH1 axis and its pivotal role in breast cancer proliferation and metastasis. These findings propose a novel therapeutic strategy for breast cancer patients and lays a foundation for its clinical detection and treatment evaluation.

Nebivolol ameliorates sepsis-evoked kidney dysfunction by targeting oxidative stress and TGF-β/Smad/p53 pathway

Sepsis is a potential fetal organ destruction brought on through an overzealous immunologic reaction to infection, causing severe inflammation, septic shock, and damage to different organs. Although there has been progress in the identification and controlling of clinical sepsis, the fatality rates are still significant. This study, for the first time, intended to examine the possible ameliorative impact of Nebivolol, a β1-adrenergic antagonist antihypertensive drug, against nephrotoxicity resulted from cecal ligation and puncture (CLP)-induced sepsis in rats, on molecular basis. Sixty male Wistar albino rats were chosen. Oxidative stress indicators and biochemical markers of kidney activity were evaluated. Inflammatory mediators, fibrosis- and apoptosis-related proteins and gene expressions were investigated. Moreover, renal histopathological investigation was performed. CLP-induced nephrotoxicity characterized by markedly elevated serum levels of creatinine, blood urea nitrogen, uric acid, and renal malondialdhyde. On the other hand, it decreased serum total protein level, renal superoxide dismutase activity and reduced glutathione level. Additionally, it significantly elevated the renal inflammatory mediators (tumor necrosis factor-alpha, ilnerlukin (IL)-6, and IL-1β) and Caspase-3 protein, reduced IL-10 level, amplified the expression of transforming growth factor-beta 1 (TGF-β1), p-Smad2/3 and alpha-smooth-muscle actin proteins, downregulated the B cell lymphoma-2 (Bcl-2) gene and elevated the transcription of Bcl-2-associated X-protein (Bax), p53 and Nuclear factor-kappa B (NF-κB) genes. Furtheremor, kidney tissues exhibited significant histopathological changes with CLP. On the contrary, Nebivolol significantly improved all these biochemical changes and enhanced the histopathological alterations obtained by CLP. This research showed, for the first time, that Nebivolol effectively mitigated the CLP-induced kidney dysfunction via its antioxidant, antifibrotic and anti-apoptotic activity through modulation of oxidative stress, TGF-β/NF-κB and TGF-β/Smad/p53 signaling pathways.

Circ6834 suppresses non-small cell lung cancer progression by destabilizing ANHAK and regulating miR-873-5p/TXNIP axis

BACKGROUND

Circular RNAs (circRNAs) play important roles in cancer progression and metastasis. However, the expression profiles and biological roles of circRNAs in non-small cell lung cancer (NSCLC) remain unclear.

METHODS

In this study, we identified a novel circRNA, hsa_circ_0006834 (termed circ6834), in NSCLC by RNA-seq and investigated the biological role of circ6834 in NSCLC progression in vitro and in vivo. Finally, the molecular mechanism of circ6834 was revealed by tagged RNA affinity purification (TRAP), western blot, RNA immunoprecipitation, dual luciferase reporter gene assays and rescue experiments.

RESULTS

Our results showed that circ6834 was downregulated in NSCLC tumor tissues and cell lines. Circ6834 overexpression inhibited NSCLC cell growth and metastasis both in vitro and in vivo, while circ6834 knockdown had the opposite effect. We found that TGF-β treatment decreased circ6834 expression, which was associated with the QKI reduction in NSCLC cells and circ6834 antagonized TGF-β-induced EMT and metastasis in NSCLC cells. Mechanistically, circ6834 bound to AHNAK protein, a key regulator of TGF-β/Smad signaling, and inhibited its stability by enhancing TRIM25-mediated ubiquitination and degradation. In addition, circ6834 acted as a miRNA sponge for miR-873-5p and upregulated TXNIP gene expression, which together inactivated the TGF-β/Smad signaling pathway in NSCLC cells.

CONCLUSION

In conclusion, circ6834 is a tumor-suppressive circRNA that inhibits NSCLC progression by forming a negative regulatory feedback loop with the TGF-β/Smad signaling pathway and represents a novel therapeutic target for NSCLC.

N6-methyladenosine modification and post-translational modification of epithelial-mesenchymal transition in colorectal cancer

Colorectal cancer is a leading cause of cancer-related mortality worldwide. Traditionally, colorectal cancer has been recognized as a disease caused by genetic mutations. However, recent studies have revealed the significant role of epigenetic alterations in the progression of colorectal cancer. Epithelial-mesenchymal transition, a critical step in cancer cell metastasis, has been found to be closely associated with the tumor microenvironment and immune factors, thereby playing a crucial role in many kinds of biological behaviors of cancers. In this review, we explored the impact of N6-methyladenosine and post-translational modifications (like methylation, acetylation, ubiquitination, SUMOylation, glycosylation, etc.) on the process of epithelial-mesenchymal transition in colorectal cancer and the epigenetic regulation for the transcription factors and pathways correlated to epithelial-mesenchymal transition. Furthermore, we emphasized that the complex regulation of epithelial-mesenchymal transition by epigenetics can provide new strategies for overcoming drug resistance and improving treatment outcomes. This review aims to provide important scientific evidence for the prevention and treatment of colorectal cancer based on epigenetic modifications.

Exploiting transcription factors to target EMT and cancer stem cells for tumor modulation and therapy

Transcription factors (TFs) are essential in controlling gene regulatory networks that determine cellular fate during embryogenesis and tumor development. TFs are the major players in promoting cancer stemness by regulating the function of cancer stem cells (CSCs). Understanding how TFs interact with their downstream targets for determining cell fate during embryogenesis and tumor development is a critical area of research. CSCs are increasingly recognized for their significance in tumorigenesis and patient prognosis, as they play a significant role in cancer initiation, progression, metastasis, and treatment resistance. However, traditional therapies have limited effectiveness in eliminating this subset of cells, allowing CSCs to persist and potentially form secondary tumors. Recent studies have revealed that cancer cells and tumors with CSC-like features also exhibit genes related to the epithelial-to-mesenchymal transition (EMT). EMT-associated transcription factors (EMT-TFs) like TWIST and Snail/Slug can upregulate EMT-related genes and reprogram cancer cells into a stem-like phenotype. Importantly, the regulation of EMT-TFs, particularly through post-translational modifications (PTMs), plays a significant role in cancer metastasis and the acquisition of stem cell-like features. PTMs, including phosphorylation, ubiquitination, and SUMOylation, can alter the stability, localization, and activity of EMT-TFs, thereby modulating their ability to drive EMT and stemness properties in cancer cells. Although targeting EMT-TFs holds potential in tackling CSCs, current pharmacological approaches to do so directly are unavailable. Therefore, this review aims to explore the role of EMT- and CSC-TFs, their connection and impact in cellular development and cancer, emphasizing the potential of TF networks as targets for therapeutic intervention.

Ursolic acid inhibits glioblastoma through suppressing TGFβ-mediated epithelial-mesenchymal transition (EMT) and angiogenesis

Found in many fruits and plants, Ursolic acid (UA), a pentacyclic triterpene that occurs naturally, is recognized for its anti-cancer effects, especially in combating glioblastoma. However, the intricate molecular mechanisms underpinning its anti-tumor actions are still not fully understood, despite the recognition of these effects. By examining the functions of epithelial-mesenchymal transition (EMT) and angiogenesis, crucial for glioblastoma progression, and their regulation through Transforming Growth Factor Beta (TGFβ) - a key marker for glioblastoma, our research aims to fill this knowledge gap. This study explores how ursolic acid can block the progression of glioblastoma by precisely targeting TGFβ-triggered EMT and angiogenesis. The findings show that UA successfully blocks the spread, movement, and invasion of glioblastoma cells. Accompanying this, there is a significant reduction in the expression of TGFβ and crucial EMT indicators like snail and vimentin. Furthermore, UA shows a reduction in angiogenesis that depends on the dosage, highlighted by decreased vascular endothelial growth factor (VEGF) in human umbilical vein endothelial cells (HUVECs). Interestingly, increased TGFβ expression in U87 and U251 glioblastoma cell lines was found to weaken UA's anti-tumor properties, shedding more light on TGFβ's critical function in glioblastoma's pathology. Supporting these laboratory results, UA also showed considerable inhibition of tumor growth in a glioblastoma xenograft mouse model. Overall, our research emphasizes Ursolic acid's promise as a new treatment for glioblastoma and clarifies its action mechanism, mainly by inhibiting TGFβ signaling and thereby EMT and angiogenesis.

Collagen Anchoring Protein-Nucleic Acid Chimeric Probe for In Situ In Vivo Mapping of a Tumor-Specific Protease

In situ analysis of biomarkers in the tumor microenvironment (TME) is important to reveal their potential roles in tumor progression and early diagnosis of tumors but remains a challenge. In this work, a bottom-up modular assembly strategy was proposed for a multifunctional protein-nucleic chimeric probe (PNCP) for in situ mapping of cancer-specific proteases. PNCP, containing a collagen anchoring module and a target proteolysis-responsive isothermal amplification sensor module, can be anchored in the collagen-rich TME and respond to the target protease in situ and generate amplified signals through rolling cycle amplification of tandem fluorescent RNAs. Taking matrix metalloproteinase 2 (MMP-2), a tumor-associated protease, as the model, the feasibility of PNCP was demonstrated for the in situ detection of MMP-2 activity in 3D tumor spheroids. Moreover, in situ in vivo mapping of MMP-2 activity was also achieved in a metastatic solid tumor model with high sensitivity, providing a useful tool for evaluating tumor metastasis and distinguishing highly aggressive forms of tumors.

Targeting Glucose Metabolism in Cancer Cells as an Approach to Overcoming Drug Resistance

The "Warburg effect" consists of a metabolic shift in energy production from oxidative phosphorylation to glycolysis. The continuous activation of glycolysis in cancer cells causes rapid energy production and an increase in lactate, leading to the acidification of the tumour microenvironment, chemo- and radioresistance, as well as poor patient survival. Nevertheless, the mitochondrial metabolism can be also involved in aggressive cancer characteristics. The metabolic differences between cancer and normal tissues can be considered the Achilles heel of cancer, offering a strategy for new therapies. One of the main causes of treatment resistance consists of the increased expression of efflux pumps, and multidrug resistance (MDR) proteins, which are able to export chemotherapeutics out of the cell. Cells expressing MDR proteins require ATP to mediate the efflux of their drug substrates. Thus, inhibition of the main energy-producing pathways in cancer cells, not only induces cancer cell death per se, but also overcomes multidrug resistance. Given that most anticancer drugs do not have the ability to distinguish normal cells from cancer cells, a number of drug delivery systems have been developed. These nanodrug delivery systems provide flexible and effective methods to overcome MDR by facilitating cellular uptake, increasing drug accumulation, reducing drug efflux, improving targeted drug delivery, co-administering synergistic agents, and increasing the half-life of drugs in circulation.

Identification of a new risk score model based on hypoxia and EMT-related genes for predicting lung squamous cell carcinoma prognosis

A complicated analysis of the prognostic characteristics of lung squamous cell carcinoma (LUSC) is needed. The aim of this study was to develop a risk score model to predict immunotherapeutic response and prognosis for patients with LUSC. A hypoxia and epithelial-mesenchymal transition-related risk score model was developed for prediction of LUSC. The correlation between risk score and clinical characteristics was determined. The single sample gene set enrichment analysis algorithm was utilized to determine the abundance of cell infiltration in tumor immune microenvironment in LUSC. The predictive value of risk score model in response to immunotherapy was evaluated. A hypoxia and epithelial-mesenchymal transition-related risk score model was constructed. This risk score model was correlated with the overall survival of LUSC. Patients with low-risk presented a high survival possibility. The high-risk group was involved in ECM receptor interaction, complement and coagulation cascades, intestinal immune network for IgA production. Finally, patients with low-risk score had significant clinical benefit. The risk score model was constructed to predict immunotherapeutic response and prognosis for patients with LUSC. In addition to identifying LUSC patients with poor survival, the results provide more information for the immune immunotherapy and microenvironment for LUSC.

AZGP1 activation by lenvatinib suppresses intrahepatic cholangiocarcinoma epithelial-mesenchymal transition through the TGF-β1/Smad3 pathway

Intrahepatic cholangiocarcinoma (ICC) is a primary liver malignancy and is characterized by highly aggressive and malignant biological behavior. Currently, effective treatment strategies are limited. The effect of lenvatinib on ICC is unknown. In this study, we found that AZGP1 was the key target of lenvatinib in ICC, and its low expression in ICC cancer tissues was associated with a poor prognosis in patients. Lenvatinib is a novel AZGP1 agonist candidate for ICC that inhibits ICC-EMT by regulating the TGF-β1/Smad3 signaling pathway in an AZGP1-dependent manner. Furthermore, we found that lenvatinib could increase AZGP1 expression by increasing the acetylation level of H3K27Ac in the promoter region of the AZGP1 gene, thereby inhibiting EMT in ICC cells. In conclusion, lenvatinib activates AZGP1 by increasing the acetylation level of H3K27Ac on the AZGP1 promoter region and regulates the TGF-β1/Smad3 signaling pathway in an AZGP1-dependent manner to inhibit ICC-EMT. This study offers new insight into the mechanism of lenvatinib in the treatment of ICC and provides a theoretical basis for new treatment methods.

The role of lncRNAs and exosomal lncRNAs in cancer metastasis

Tumor metastasis is the main reason for cancer-related death, but there is still a lack of effective therapeutic to inhibit tumor metastasis. Therefore, the discovery and study of new tumor metastasis regulators is a prominent measure for cancer diagnosis and treatment. Long non-coding RNA (lncRNA) is a type of non-coding RNAs over 200 bp in length. It has been shown that the abnormally expressed lncRNAs promote tumor metastasis by participating in the epithelial-to-mesenchymal transition (EMT) process, altering the metastatic tumor microenvironment, or changing the extracellular matrix. It is,thus, critical to explore the regulation of lncRNAs expression in cells and the molecular mechanism of lncRNA-mediated cancer metastasis. Simultaneously, it has been shown that lncRNA is one kind of the main components of exosomes, which protects lncRNAs from being rapidly degraded. Meanwhile, the components of exosomes are parent-specific, making exosomal lncRNAs to be potential tumor metastasis markers and therapeutic targets. In view of this, we also summarized the aberrant enrichment of lncRNAs in exosomes and their role in metastatic cancer. The aberrant lncRNAs and exosomal lncRNAs gradually become biomarkers and therapeutic targets for tumor metastatic, and the potential of lncRNAs in therapeutics are studied here. Besides, the lncRNA-related databases, which could greatly facilitate in the study of lncRNAs and exosomal lncRNAs in metastatic of cancer are included in this review.

Sparganii Rhizoma alleviates pulmonary fibrosis by inhibiting fibroblasts differentiation and epithelial-mesenchymal transition mediated by TGF-β1/ Smad2/3 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Pulmonary fibrosis (PF), a lethal lung disease, can lead to structural destruction of the alveoli until death. Sparganii Rhizoma (SR), primarily distributed in East Asia, has been used clinically for hundreds of years against organ fibrosis and inflammation.

AIM OF THE STUDY

We intended to verify the effect of SR alleviate PF and further explore mechanisms.

METHODS

Murine model of PF was established by endotracheal infusion of bleomycin. We detected the anti-PF effect of SR through lung coefficient, hydroxyproline content, lung function and pathological staining. Then, we used Western Blot and RT-PCR to verify the mechanism. In vitro experiments, MRC-5 and BEAS-2B were induced to phenotypic transformation by TGF-β1 and then RT-PCR, WB and IF were conducted to verify the effect of SR.

RESULTS

SR significantly reduced BLM-induced PF in mice, improved lung function, slowed the degree of lung tissue lesions, and reduced collagen deposition. SR alleviated PF by inhibiting fibroblasts differentiation and epithelial-mesenchymal transition. In vivo studies explored the mechanism and found that it was related to TGF-β1/Smad2/3 pathway.

CONCLUSIONS

Our research proved SR could effectively treat PF, providing a fresh idea and approach for the treatment of PF with traditional Chinese medicine.

Cyclin-dependent kinase subunit2 (CKS2) promotes malignant phenotypes and epithelial-mesenchymal transition-like process in glioma by activating TGFβ/SMAD signaling

BACKGROUND

Gliomas are a group of primary intracranial tumors with high morbidity and mortality. The previous researches indicated a crucial role of CKS2 (cyclin-dependent kinases regulatory subunit 2) in hepatocellular carcinoma and breast cancer; however, little is known about the molecular mechanism of CKS2 in the tumorigenesis and epithelial-mesenchymal transition-like (EMT) process in glioma.

METHODS

Datasets for bioinformatics analysis were obtained from the GEO, TCGA and CGGA databases. qRT-PCR, western blotting (WB), and immunohistochemistry (IHC) assays were used to investigate the expression patterns of CKS2 among glioma and brain tissues. Glioma cells were transfected with small interfering RNA/overexpression plasmid against CKS2, then clone formation assay, CCK-8, wound healing, Transwell assay, and flow cytometry were performed to detect changes in cell viability, invasiveness, and the apoptosis rate. Markers of cell invasion, apoptosis, EMT and TGFβ/SMAD signaling were evaluated by WB and immunofluorescence (IF) assays.

RESULTS

We found that CKS2 overexpression correlates with poor prognosis in human glioma and knockdown of CKS2 could inhibit cell proliferation, migration, invasion, and induced apoptosis in glioma cells. Besides, we also found that knockdown of CKS2 could reverse the EMT process via modulating EMT-related molecules. Glioma cells with overexpression of CKS2 were constructed to confirmed the fact that CKS2 induced nucleocytoplasmic translocation of SMAD2/3 and activated TGFβ/SMAD pathway, then upregulated its downstream targets expression, while inhibition of TGFβ/SMAD (by TGFβ inhibitor LY2157299 or SMAD4 siRNA) could reverse the tumor-promoting effects and malignant phenotype caused by CKS2 overexpression.

CONCLUSIONS

We identified CKS2 as a critical contributor to the gliomagenesis, which might provide a novel therapeutic target for inhibiting the spread and infiltration of glioma.

Targeted tumor killing by pomegranate polyphenols: Pro-oxidant role of a classical antioxidant

One of the key biochemical features that distinguish a cancer cell from normal cells is its persistent pro-oxidative state that leads to intrinsic oxidative stress. Malignant cells have evolved sophisticated adaptation systems that involve high dependency on antioxidant functions and upregulation of pro-survival molecules to counteract the deleterious effects of reactive species and to maintain dynamic redox balance. This situation renders them vulnerable to further oxidative challenges by exogenous agents. In the present study, we advocated that pomegranate polyphenols act as pro-oxidants and trigger ROS-mediated apoptosis in cancer cells. With the help of both in vitro and in vivo models, we have established that pomegranate fruit extract (PFE) can cause a significant reduction in tumor proliferation while leaving normal tissues and cells unharmed. Administration of PFE (0.2% v/v) in Erhlich's ascites carcinoma-bearing mice for 3 weeks, inhibited the nuclear factor (erythroid-derived 2)-like 2-antioxidant response element signaling cascade, increased intracellular reactive oxygen species content, altered glutathione cycle thereby activating reactive oxygen species-induced apoptotic pathway in Erhlich's ascites carcinoma cells. Moreover, PFE mitigated epithelial to mesenchymal transition and migration in triple negative breast cancer cells (MDA-MB 231 cells) by down-regulating nuclear factor kappa light-chain-enhancer of activated B cells. Pre-treatment of tumor cells with N-acetyl cysteine protected these cells from undergoing PFE-induced apoptosis while siRNA-mediated silencing of Nuclear factor (erythroid-derived 2)-like 2 and nuclear factor kappa light-chain-enhancer of activated B cells in tumor cells increased the cytotoxic potential and pro-oxidative activity of PFE, indicating a clear role of these transcription factors in orchestrating the anticancer/pro-oxidative properties of PFE. The seminal findings provided may be exploited to develop potential therapeutic targets for selective killing of malignant cells.

Nephroprotective effect of AT-MSCs against cisplatin-induced EMT is improved by azilsartan via attenuating oxidative stress and TGF-β/Smad signaling

The nephrotoxicity of cisplatin (CIS) is a significant complication that challenges its clinical applicability. The epithelial to mesenchymal transition (EMT) may be included in the pathogenesis of CIS-evoked nephrotoxicity. Therefore, the current study aimed to evaluate, for the first time, the possible protective effect of AZL and/or AT-MSCs against CIS-induced EMT in rats on molecular bases. Fifty-four healthy Wistar male albino rats were used in this study. Different biochemical markers of kidney function as well as oxidative stress parameters were investigated. Additionally, renal histopathological study was performed. The expression of EMT-related proteins and genes was evaluated by western blotting and qRT-PCR. CIS markedly increased SCr, BUN, uric acid and renal MDA levels, with concomitant decrease in serum total protein, renal GSH level and SOD activity. Furthermore, it suppressed the expression of Cdh1 gene, increased the α-SMA, Acta2, Cdh2 and Vim genes expression, down regulated the expression of E-cad protein and up-regulated the α-SMA, TGF-β1, p-Smad2/3 and Snail proteins expression. Kidney tissues showed severe histopathological alterations and extensive collagen accumulation. Conversely, the treatment with either AZL or AT-MSCs significantly attenuated these alterations caused by CIS. Interestingly, the combined therapy of AZL and AT-MSCs has a superior ameliorative effect than AT-MSCs alone. In conclusion, this study, for the first time, revealed that AZL and/ or AT-MSCs successfully ameliorated the CIS-induced EMT via the inhibition of oxidative stress and TGF-β/Smad signaling pathway. Intriguingly, AZL enhanced the effect of AT-MSCs making them promising agents for kidney protection against CIS-induced EMT.

Upregulation of the long non-coding RNA, LIPCAR promotes proliferation, migration, and metastasis of hepatocellular carcinoma

BACKGROUND: Hepatocellular carcinoma (HCC) early diagnosis remains a challenge to date. Alpha-feto protein, though less sensitive remains widely used for both diagnosis and prognosis. Recently however, a number of molecular biomarkers have been suggested as alternatives to Alpha feto protein, especially for early diagnosis. OBJECTIVE: To determine the role of the long non-coding RNA, LIPCAR in the pathogenesis and early diagnosis of hepatocellular carcinoma. METHODS: Quantitative real-time PCR, and Fluorescence in situ hybridization assays were conducted to determine LIPCAR expression in HCC vs normal blood samples, and HCC cell lines vs normal liver cell lines. Transfection was done to upregulate LIPCAR in one HCC cell line, and used to study cell proliferation, migration, apoptosis and epithelial-mesenchymal transformation. Animal experiment was finally done to determine its effect on metastasis. RESULTS: LIPCAR was significantly upregulated in HCC blood samples and HCC cell lines compared to their respective normal ones. Its overexpression promoted hepatocellular carcinoma cell proliferation, and migration, while inhibiting apoptosis. Its overexpression also promoted epithelial-mesenchymal transformation in hepatocellular carcinoma cells, and metastasis in vivo. CONCLUSION: The study demonstrated that the lncRNA, LIPCAR is significantly upregulated in hepatocellular carcinoma patients and that its upregulation promotes HCC proliferation, migration, and metastases.

The molecular mechanisms and therapeutic strategies of EMT in tumor progression and metastasis

Epithelial–mesenchymal transition (EMT) is an essential process in normal embryonic development and tissue regeneration. However, aberrant reactivation of EMT is associated with malignant properties of tumor cells during cancer progression and metastasis, including promoted migration and invasiveness, increased tumor stemness, and enhanced resistance to chemotherapy and immunotherapy. EMT is tightly regulated by a complex network which is orchestrated with several intrinsic and extrinsic factors, including multiple transcription factors, post-translational control, epigenetic modifications, and noncoding RNA-mediated regulation. In this review, we described the molecular mechanisms, signaling pathways, and the stages of tumorigenesis involved in the EMT process and discussed the dynamic non-binary process of EMT and its role in tumor metastasis. Finally, we summarized the challenges of chemotherapy and immunotherapy in EMT and proposed strategies for tumor therapy targeting EMT.

Loss of intercellular bridges in the depth of invasion measurement area is a novel negative prognostic factor for oral squamous cell carcinoma: A retrospective study

OBJECTIVE

This study aimed to evaluate intercellular bridges in the depth of invasion (DOI) measurement area as prognostic factors in oral squamous cell carcinoma (OSCC).

STUDY DESIGN

The mode of invasion was determined based on the Yamamoto-Kohama classification system by observing the hematoxylin-eosin-stained whole-slide images of specimens obtained from 78 patients with OSCC, and the clinicopathologic features were characterized. The presence of intercellular bridges was analyzed in 46 patients with Yamamoto-Kohama classification grade ≥3 whose DOI was measured by dividing the measurement area into 3 parts: the surface, center, and front of the tumor.

RESULTS

Univariate analyses identified lymph node metastasis, loss of intercellular bridges in the DOI measurement area, DOI of ≥4500 µm, and pattern of invasion 4C-4D as negative prognostic factors. Multivariate analyses revealed that lymph node metastasis and the loss of intercellular bridges in the entire area were independent factors, with hazard ratios of 9.34 (95% confidence interval, 2.09-42.03; P = .003) and 3.64 (95% confidence interval, 1.10-11.99; P = .045), respectively.

CONCLUSIONS

Loss of intercellular bridges in the DOI measurement area is a negative prognostic factor for OSCC and may be useful in selecting treatment.

Construction of ovarian metastasis-related immune signature predicting prognosis of gastric cancer patients

BACKGROUND

Ovarian metastasis (OM) results in poor survival of gastric cancer (GC) patients. While immunotherapy has emerged as a promising approach for late-stage GC, validated immune-related prognostic signatures still remain in need. In this study, we constructed an ovarian metastasis- and immune-related prognostic signature (OMIRPS), characterized the molecular and immune features of OMIRPS-categorized subgroups and predicted their potential response to immunotherapy.

METHODS

Three individual cohorts were used to construct and evaluate OMIRPS: RNA-seq of matched primary GC and OM from Fudan University Shanghai Cancer Center (FUSCC) (discovery cohort, n = 4), The Cancer Genome Atlas (TCGA) (training cohort, n = 544) and GSE84437 (validation cohort, n = 433). Differentially expressed genes (DEGs) identified between primary GC and OM and immune-related genes (IRGs) from the ImmPort and InnateDB databases were used to identify immune-related prognostic hub genes, which were further used to construct OMIRPS by using LASSO regression analysis. Prognosis, molecular characteristics, immune features, and differential immunotherapy efficacy between different OMIRPS subgroups were analyzed.

RESULTS

Functional analyses of DEGs revealed the significance of immune-related signatures and pathways in the OM. Immune-related prognostic hub genes including TNFRSF18, CARD11, BCL11B, NRP1, BNIP3L, and ATF3 were utilized to construct OMIRPS, which was identified as an independent prognostic factor. Comprehensive analyses unveiled the distinctive molecular and immune characteristics of OMIRPS-high and -low subgroup in regard to enriched pathways, mutation rate, tumor mutation burden, microsatellite instability status, infiltrated immune cell, immune exclusion score, and the prediction of immunotherapy efficacy. Additionally, OMIRPS was associated with Immune Subtypes with borderline significance.

CONCLUSIONS

RNA-seq of paired primary and ovarian metastatic tumors unveiled the significance of immune-related pathways and tumor immune microenvironment in OM. OMIRPS served as a promising biomarker to predict the prognosis of GC patients and distinguish the molecular features, immune characteristics, and efficacy of immunotherapy between different subgroups.

Ets family proteins regulate the EMT transcription factors Snail and ZEB in cancer cells

The epithelial–mesenchymal transition (EMT) is a crucial morphological event that occurs during epithelial tumor progression. Snail and ZEB1/2 (ZEB1 and ZEB2), known as EMT transcription factors, are key regulators of this transition. ZEB1/2 are positively correlated with EMT phenotypes and the aggressiveness of cancers. On the contrary, Snail is also correlated with the aggressiveness of cancers, but is not correlated with the expression of EMT marker proteins. Snail is induced by transforming growth factor‐β (TGF‐β), a well‐known inducer of EMT, in various cancer cells. Interestingly, Snail induction by TGF‐β is markedly enhanced by active Ras signals. Thus, cancer cells harboring an active Ras mutation exhibit a drastic induction of Snail by TGF‐β alone. Here, we found that members of the E26 transformation‐specific (Ets) transcription factor family, Ets1 and Ets2, contribute to the upregulation of both Snail and ZEB1/2. Snail induction by TGF‐β and active Ras is dramatically inhibited using siRNAs against both Ets1 and Ets2 together, but not on their own; in addition, siRNAs against both Ets1 and Ets2 also downregulate the constitutive expression of Snail and ZEB1/2 in cancer cells. Examination of several alternatively spliced variants of Ets1 revealed that p54‐Ets1, which includes exon VII, but not p42‐Ets1, which excludes exon VII, regulates the expression of the EMT transcription factors, suggesting that Ets1 is a crucial molecule for regulating Snail and ZEB1/2, and thus cancer progression is mediated through post‐translational modification of the exon VII domain.

Interferon-induced transmembrane protein 2 promotes epithelial-mesenchymal transition by activating transforming growth factor-β1/small mother against decapentaplegic 2 signaling in gastric cancer

BACKGROUND

Gastric cancer (GC) is one of the most prevalent malignancy around the world. Primary tumor cells are enabled to invade and migrate into adjacent normal tissues to form secondary tumors. Epithelial-mesenchymal transitions (EMT) plays a pivotal role in facilitating tumor progression. Abundant evidence suggested that the transforming growth factor-β1 (TGF-β1) triggered the process of EMT. Nonetheless, the precise molecular mechanisms underlying EMT requires further elucidation, and there still lacks effective specific therapeutic target. In our recent research, we demonstrated that the interferon (IFN)-induced transmembrane protein 2 (IFITM2) promoted the growth and metastasis of GC. However, it remains unclear whether IFITM2 involves in TGF-β1 mediated EMT in GC.

METHODS AND RESULTS

In the present research, we investigated the functional role of IFITM2 in EMT process and TGF-β1 signaling pathway in two GC cell lines. We noticed that silencing IFITM2 can effectively inhibit TGF-β1 signaling mediated EMT by regulating down stream small mother against decapentaplegic (SMAD) 2/3 and transcription factors.This finding was further determined in both tumor tissues from GC patients and normal tissues adjacent to cancer. Our data demonstrated the key role of IFITM2 in TGF-β1 signaling and EMT in GC.

CONCLUSION

The findings enriched our understanding of the underlying mechanism in EMT during the progression of GC. In addition, IFITM2 would be a potential target for treating GC and other malignant tumors.

The protective effects of granulocyte-macrophage colony-stimulating factor against radiation-induced lung injury

Background

Radiation-induced lung injury (RILI) is a common complication of thoracic cancer radiation therapy. Currently, there is no effective treatment for RILI. RILI is associated with chronic inflammation, this injury is perpetuated by the stimulation of chemokines and proinflammatory cytokines. Recent studies have demonstrated that granulocyte-macrophage colony-stimulating factor (GM-CSF) plays a pivotal role in inflammation and fibrosis. This study aimed to investigate the protective effect of GM-CSF against the development of RILI in lung tissue.

Method

First, a single fraction of radiation at a dose of 16 Gy was targeted at the entire thorax of wild-type (WT) C57BL/6 mice and GM-CSF^–/– mice to induce RILI. Second, we detected the radioprotective effects of GM-CSF by measuring the inflammatory biomarkers and fibrosis alteration on radiated lung tissues. Furthermore, we investigated the potential mechanism of GM-CSF protective effects in RILI.

Results

The GM-CSF^–/– mice sustained more severe RILI than the WT mice. RILI was significantly alleviated by GM-CSF treatment. Intraperitoneally administered GM-CSF significantly inhibited inflammatory cytokine production and decreased epithelial-mesenchymal transition (EMT) in the RILI mouse model.

Conclusions

GM-CSF was shown to be an important modulator of RILI through regulating inflammatory cytokines, which provides a new strategy for the prevention and treatment of RILI.

TGF-β acts as a dual regulator of COX-2/PGE2 tumor promotion depending of its cross-interaction with H-Ras and Wnt/β-catenin pathways in colorectal cancer cells

Transforming growth factor-β (TGF-β) plays a dual role acting as tumor promoter or suppressor. Along with cyclooxygenase-2 (COX-2) and oncogenic Ras, this multifunctional cytokine is deregulated in colorectal cancer. Despite their individual abilities to promote tumor growth and invasion, the mechanisms of cross regulation between these pathways is still unclear. Here, we investigate the effects of TGF-β, Ras oncogene and COX-2 in the colorectal cancer context. We used colon adenocarcinoma cell line HT-29 and Ras-transformed IEC-6 cells, both treated with prostaglandin E₂ (PGE₂ ), TGF-β or a combined treatment with these agents. We demonstrated that PGE₂ alters the subcellular localization of E-cadherin and β-catenin and enhanced the tumorigenic potential in HT-29 cells. This effect was inhibited by TGF-β, indicating a tumor suppressor role. Conversely, in Ras-transformed IEC-6 cells, TGF-β induced COX-2 expression and increased invasiveness, acting as a tumor promoter. In IEC-6 Ras-transformed cells, TGF-β increased nuclear β-catenin and Wnt/β-catenin activation, opposite to what was seen in the PGE₂ and TGF-β joint treatment in HT-29 cells. Together, our findings show that TGF-β increases COX-2 levels and induces invasiveness cooperating with Ras in a Wnt/β-catenin activation-dependent manner. This shows TGF-β dual regulation over COX-2/PGE₂ tumor promotion depending on the H-Ras and Wnt/β-catenin pathways activation status in intestinal cancer cells.

Emerging Concepts of Hybrid Epithelial-to-Mesenchymal Transition in Cancer Progression

Epithelial mesenchymal transition (EMT) is a complex process through which epithelial (E) cells lose their adherens junctions, transform into mesenchymal (M) cells and attain motility, leading to metastasis at distant organs. Nowadays, the concept of EMT has shifted from a binary phase of interconversion of pure E to M cells and vice versa to a spectrum of E/M transition states preferably coined as hybrid/partial/intermediate EMT. Hybrid EMT, being a plastic transient state, harbours cells which co-express both E and M markers and exhibit high tumourigenic properties, leading to stemness, metastasis, and therapy resistance. Several preclinical and clinical studies provided the evidence of co-existence of E/M phenotypes. Regulators including transcription factors, epigenetic regulators and phenotypic stability factors (PSFs) help in maintaining the hybrid state. Computational and bioinformatics approaches may be excellent for identifying new factors or combinations of regulatory elements that govern the different EMT transition states. Therapeutic intervention against hybrid E/M cells, though few, may evolve as a rational strategy against metastasis and drug resistance. This review has attempted to present the recent advancements on the concept and regulation of the process of hybrid EMT which generates hybrid E/M phenotypes, evidence of intermediate EMT in both preclinical and clinical setup, impact of partial EMT on promoting tumourigenesis, and future strategies which might be adapted to tackle this phenomenon.

HLJ2 Effectively Ameliorates Colitis-Associated Cancer via Inhibition of NF-κB and Epithelial-Mesenchymal Transition

Introduction

Colitis-associated cancer (CAC) accounts for approximately 15% of IBD patient mortalities. However, currently available anti-CAC drugs possess many disadvantages including safety, specificity and side effects. Therefore, the development of novel anti-CAC compounds is imperative. HLJ2 was a monomeric compound synthesized by our institute and reported to have an effect on ulcer colitis.

Methods

In vivo the AOM/DSS-induced CAC model was used to evaluate the effects of HLJ2 on ameliorating CAC symptoms, immunohistochemical analysis was used to analyze the pathological damage to colons and epithelial–mesenchymal transition was for changes of cytokines. In vitro, flow cytometric analysis, immunofluorescence and Western blot were used to detect the inhibition effect of HLJ2 on nuclear factor-κB and epithelial–mesenchymal transition in TGF-β1-stimulated SW480 cells.

Results

In the AOM/DSS animal model, HLJ2 was demonstrated to inhibit the secretion of inflammatory cytokines and nuclear factor-κB, levels of tumorigenesis-related proteins including snail, and finally inhibited a key step in metastasis, epithelial–mesenchymal transition. In vitro, HLJ2 was also shown to inhibit nuclear factor-κB and epithelial–mesenchymal transition in TGF-β1-stimulated SW480 cells in accordance with in vivo results. Meanwhile, the nuclear factor-κB inhibitor could interrupt the effect of HLJ2 on epithelial–mesenchymal transition.

Discussion

HLJ2 may ameliorate CAC through inhibiting nuclear factor-κB and then downstream epithelial–mesenchymal transition. The combination of the obvious improvement in effects on CAC without obvious side effects suggests that HLJ2 could be developed as a potential CAC therapeutic candidate.

Overcoming epithelial-mesenchymal transition-mediated drug resistance with monensin-based combined therapy in non-small cell lung cancer

BACKGROUND

The epithelial-mesenchymal transition (EMT) is a key process in tumor progression and metastasis and is also associated with drug resistance. Thus, controlling EMT status is a research of interest to conquer the malignant tumors.

MATERIALS AND METHODS

A drug repositioning analysis of transcriptomic data from a public cell line database identified monensin, a widely used in veterinary medicine, as a candidate EMT inhibitor that suppresses the conversion of the EMT phenotype. Using TGF-β-induced EMT cell line models, the effects of monensin on the EMT status and EMT-mediated drug resistance were assessed.

RESULTS

TGF-β treatment induced EMT in non-small cell lung cancer (NSCLC) cell lines and the EGFR-mutant NSCLC cell lines with TGF-β-induced EMT acquired resistance to EGFR-tyrosine kinase inhibitor. The addition of monensin effectively suppressed the TGF-β-induced-EMT conversion, and restored the growth inhibition and the induction of apoptosis by the EGFR-tyrosine kinase inhibitor.

CONCLUSION

Our data suggested that combined therapy with monensin might be a useful strategy for preventing EMT-mediated acquired drug resistance.

Role of the RNA-binding protein La in cancer pathobiology

RNA-binding proteins are important regulators of RNA metabolism and are of critical importance in all steps of the gene expression cascade. The role of aberrantly expressed RBPs in human disease is an exciting research field and the potential application of RBPs as a therapeutic target or a diagnostic marker represents a fast-growing area of research.Aberrant overexpression of the human RNA-binding protein La has been found in various cancer entities including lung, cervical, head and neck, and chronic myelogenous leukaemia. Cancer-associated La protein supports tumour-promoting processes such as proliferation, mobility, invasiveness and tumour growth. Moreover, the La protein maintains the survival of cancer cells by supporting an anti-apoptotic state that may cause resistance to chemotherapeutic therapy.The human La protein represents a multifunctional post-translationally modified RNA-binding protein with RNA chaperone activity that promotes processing of non-coding precursor RNAs but also stimulates the translation of selective messenger RNAs encoding tumour-promoting and anti-apoptotic factors. In our model, La facilitates the expression of those factors and helps cancer cells to cope with cellular stress. In contrast to oncogenes, able to initiate tumorigenesis, we postulate that the aberrantly elevated expression of the human La protein contributes to the non-oncogenic addiction of cancer cells. In this review, we summarize the current understanding about the implications of the RNA-binding protein La in cancer progression and therapeutic resistance. The concept of exploiting the RBP La as a cancer drug target will be discussed.

miR-96-5p regulated TGF-β/SMAD signaling pathway and suppressed endometrial cell viability and migration via targeting TGFBR1

We previously performed high throughput RNA-seq in paired eutopic and ectopic endometrial specimen of endometriosis patients, and validated the results by qRT-PCR in endometriosis endometrial tissues. MiR-96-5p was significantly downregulated in ectopic endometrial tissues compared to eutopic tissues. In order to identify the role of miR-96-5p in endometriosis and endometrial cells, and investigate the underlying mechanisms, the Ishikawa and End1/E6E7 cell lines were transfected with miR-96-5p mimics, miR-96-5p inhibitors or TGFBR1 siRNA. The expression of TGF-β/SMAD signaling pathway components and epithelial-mesenchymal transition (EMT) markers were examined by qRT-PCR and western blot, and cell viability and migration were determined by CCK-8, transwell and wound healing assays, respectively. We discovered miR-96-5p to be significantly downregulated while TGFBR1 was distinctly up-regulated in endometriosis. Overexpression of miR-96-5p inhibited endometrial cells viability and migration, while inhibition of miR-96-5p had opposite effect. Furthermore, we confirmed TGFBR1 was a direct target of miR-96-5p. Overexpression of miR-96-5p could block the TGF-β/SMAD signaling pathway via targeting TGFBR1 and reverse the TGF-β1 induced EMT in endometrial cell lines. In conclusion, we demonstrated that miR-96-5p interacted with TGF-β/SMAD signaling pathway and blocked the TGF-β1 induced EMT in endometrial cells via directly targeting TGFBR1.

Sarcomatoid carcinoma of the pancreas with rare long-term survival: a case report

BACKGROUND

Sarcomatoid carcinoma of the pancreas (SCP) tends to have similar or even worse prognosis than that of conventional pancreatic ductal adenocarcinoma. The clinical and pathological features of SCP remain poorly characterized owing to its rarity.

CASE PRESENTATION

A 58-year-old man was admitted to our hospital with the chief complaints of upper abdominal pain and weight loss. Abdominal contrast computed tomography revealed a 5-cm low-density mass in the pancreatic body. Magnetic resonance cholangiopancreatography revealed an obstruction of the main pancreatic duct and a dilation of the distal main pancreatic duct. Based on the clinicoradiological findings, pancreatic body cancer was suspected, and the distal pancreatectomy was performed. A pathological examination revealed that the tumor was composed of an area of invasive ductal adenocarcinoma and an area of sarcomatous spindle-shaped cells; the latter component predominated. The spindle cells were immunohistochemically positive for both cytokeratin and vimentin, and thus, a pathological diagnosis of SCP was made. In addition, immunohistochemical analysis suggested the sarcomatous component might be derived from the adenocarcinoma component via the process of epithelial-mesenchymal transition. After the operation, the patient received 6 months of chemotherapy with gemcitabine. At 10 years after the operation, the patient is alive with no recurrence.

CONCLUSIONS

The current case study presented a SCP patient with long-term survival after the operation. It was worth noting that the sarcomatous component of the tumor pathologically showed lower MIB-1 labeling index compared with those in previously reported SCP cases, which might account for the long-term survival of the patient.

Inhibitory Effects of Olea europaea Leaf Extract on Mesenchymal Transition Mechanism in Glioblastoma Cells

BACKGROUND

Glioblastoma (GB) is the most aggressive form of brain tumor. Despite the current treatment methods, the survival rate of patients is very low. Therefore, there is a need to develop new therapeutic agents. The migration and invasion capacity of GB cells is related to mesenchymal transition (MT) mechanism.

MATERIALS AND METHODS

The effect of OLE on MT was determined by analysis of the Twist, Snail, Zeb1, N-cadherin and E-cadherin genes in the EMT mechanism. The effect of OLE on cell migration was determined by wound healing test.

RESULTS

2 mg/ml OLE reduced Twist, Snail, Zeb1 and N-cadherin expression and the combination of OLE + TMZ (2 mg/ml OLE + 350 mM TMZ) increased E-cadherin and reduced Twist, Zeb1 and N-cadherin. In addition, co-treatment with OLE increased TMZ-induced anti-invasion properties thought suppressing transcription factors of MT mechanism.

CONCLUSION

OLE can enhance the anti-MT activities of TMZ against GB and provide strong evidence that combined treatment with OLE and TMZ has the potential to be an effective alternative approach in GB therapy.

Epithelial-mesenchymal transition in oral squamous cell carcinoma: An insight into molecular mechanisms and clinical implications

Epithelial-mesenchymal transition (EMT) is an important event in embryonic development, fibrosis and cancer invasion. During cancer progression, the activation of EMT permits cancer cells to acquire migratory, invasive and stem-like properties. Despite recent advances in treatment, there is no improvement in the 5-year overall survival rate of oral squamous cell carcinoma (OSCC). Local recurrence and lymph node metastasis are considered to be mainly responsible for the low survival rate in OSCC. EMT plays a major role in local recurrence and lymph node metastasis of oral cancer. This review article addresses the clinical implications of EMT in OSCC and explains the molecular mechanisms of EMT, highlighting the cadherin switching and signaling pathways involved.

Piperine Inhibits TGF-β Signaling Pathways and Disrupts EMT-Related Events in Human Lung Adenocarcinoma Cells

Background: Piperine, an amide extracted from the Piper spices, exhibits strong anti-tumor properties. However, its effect on the epithelial–mesenchymal transition (EMT) process has never been investigated. Herein, we evaluate the toxic effect of piperine on lung adenocarcinoma (A549), breast adenocarcinoma (MDA-MB-231) and hepatocellular carcinoma (HepG2) cell lines, as well as its ability to inhibit EMT-related events induced by TGF-β1 treatment. Methods: The cell viability was investigated by MTT assay. Protein expression was evaluated by Western blot. Gene expression was monitored by real-time PCR. Zymography assay was employed to detect metalloproteinase (MMP) activity in conditioned media. Cell motility was assessed by the wound-healing and phagokinetic gold sol assays. Results: The results revealed that piperine was cytotoxic in concentrations over 100 µM, showing IC50 values for HepG2, MDA-MB-231 and A549 cell lines of 214, 238 and 198 µM, respectively. In order to investigate whether piperine would reverse the TGF-β1 induced-EMT, the A549 cell line was pretreated with sublethal concentrations of the natural amide followed by the addition of TGF-β1. Besides disrupting EMT-related events, piperine also inhibited both ERK 1/2 and SMAD 2 phosphorylation. Conclusions: These results suggest that piperine might be further used in therapeutic strategies for metastatic cancer and EMT-related disorders.

Ex vivo interaction between blood components and hormone-dependent breast cancer cells induces alterations associated with epithelial-mesenchymal transition and thrombosis

The prevalence of breast cancer is steadily increasing with metastasis and thromboembolic complications identified as the most common causes of death. The acquisition of an aggressive phenotype by hormone-dependent breast cancers is mediated by Transforming Growth Factor Beta 1 (TGF-β₁) expression and is associated with epithelial-mesenchymal transition (EMT) and, potentially, increased propensity for thrombosis. We investigated this phenomenon by assessing the effect of platelet-rich plasma (PRP) and whole blood (WB) on parameters of EMT and hypercoagulation in vitro. MCF-7 breast cancer cells were cultured under standard conditions, followed by co-culture with PRP or WB. Cells were processed for real-time PCR (TGF-β₁ and vimentin), electron microscopy or immunocytochemistry (TGF-β₁). Micrographs were qualitatively assessed, and real-time PCR data analyzed with PAST Statistical Software. The addition of blood components heightened TGF-β₁ immunolocalization and significantly increased corresponding gene expression. Both PRP and WB significantly increased vimentin expression and induced a shape change from a typical epithelial phenotype to a spindle-shape morphology, indicative of EMT. Fibrin fiber, network and plaque formation indicated a hypercoagulatory environment. The results thus show that in preparation for hematogenous metastasis, hormone-dependent breast cancer cells assume an aggressive phenotype associated with EMT, simultaneously increasing the propensity for the formation of thrombo-emboli.

Epithelial-mesenchymal transition may be involved in the immune evasion of circulating gastric tumor cells via downregulation of ULBP1

Background

Increasing numbers of studies have demonstrated that circulating tumor cells (CTCs) undergo a phenotypic change termed epithelial‐mesenchymal transition (EMT), and researchers have proposed that EMT might provide CTCs with increased potential to survive in the different microenvironments encountered during metastasis through various ways, such as by increasing cell survival and early colonization. However, the exact role of EMT in CTCs remains unclear.

Methods

In this study, we identified CTCs of 41 patients with gastric cancer using Cyttel‐CTC and im‐FISH (immune‐fluorescence in situ hybridization) methods, and tested the expression of EMT markers and ULBP1 (a major member of the NKG2D—natural killer [NK] group 2 member D—ligand family) on CTCs. Moreover, we investigated the relationship between the expression of EMT markers and ULBP1 on CTCs and gastric cancer cell lines.

Results

Our results showed that the CTCs of gastric cancer patients exhibited three EMT marker subtypes, and that the expression of ULBP1 was significantly lower on mesenchymal phenotypic CTCs (M⁺CTCs) than on epithelial phenotypic CTCs (E⁺CTCs). EMT induced by TGF‐β in vitro produced a similar phenomenon, and we therefore proposed that EMT might be involved in the immune evasion of CTCs from NK cells by altering the expression of ULBP1.

Conclusions

Our study indicated that EMT might play a vital role in the immune invasion of CTCs by regulating the expression of ULBP1 on CTCs. These findings could provide potential strategies for targeting the immune evasion capacity of CTCs.

MYH9 promotes cell metastasis via inducing Angiogenesis and Epithelial Mesenchymal Transition in Esophageal Squamous Cell Carcinoma

Non-muscle myosin heavy chain 9 (MYH9) is one novel low frequency mutated gene identified in esophageal squamous cell carcinoma (ESCC) using next-generation sequencing. However, its clinical relevance, potential function and mechanisms remain elusive. Methods: Genomic sequencing datas from 104 esophageal squamous cell carcinoma (ESCC) cases were screened a series of low frequency mutant genes. MYH9 was selected to further analyze its clinical significance, function and PCR-array was performed to explore its potential mechanism. Results: MHY9 is a low frequency mutant gene with a mutation frequency of 2.88% in ESCC. Immunohistochemical analysis showed that MYH9 expression was significantly higher in ESCC tumor tissues, and the expression levels were associated with lymph node metastasis of ESCC patients. Moreover, we found that MYH9 knock-down led to inhibition of cell migration and invasion. PCR-array showed MYH9 knockdown led to a significant change of genes expression associated with angiogenesis and epithelial-to-mesenchymal transition (EMT). This observation is further confirmed in TCGA database of LUSC (lung squamous cell carcinoma), CESC (cervical squamous cell carcinomas) and HNSC (head and neck squamous cell carcinoma). Conclusions: Collectively, our study identifies a novel role and mechanism of MYH9, highlights a significance of MYH9 as a metastatic biomarker, and offers potential therapeutic targets for ESCC patients harboring MYH9 mutations.

TGF-β1 stimulates epithelial-mesenchymal transition and cancer-associated myoepithelial cell during the progression from in situ to invasive breast cancer

Background

The progression of ductal carcinoma in situ (DCIS) into invasive ductal carcinoma (IDC) is prevented by normal breast myoepithelial cells. Studies have suggested that EMT-associated genes were enriched in IDC in contrast to DCIS. This paper explored the relationship and potential mechanism between myoepithelial cells and EMT-associated genes in facilitating the transformation from DCIS to breast cancer.

Methods

EMT markers and myoepithelial phenotypic markers in IDC, DCIS, and healthy breast tissue were characterized using immunohistochemical assay. Both in vivo and in vitro models were created to mimic the various cell–cell interactions in the development of invasive breast cancer.

Results

We found that EMT markers were more abundant in invasive carcinomas than DCIS and adjacent normal breast tissue. Meanwhile, TGF-β1 regulated the morphology of MCF-7 (epithelial cells substitute) migration and EMT markers during the transformation from DCIS to invasive breast cancer. Additionally, TGF-β1 also regulated invasion, migration and cytokines secretion of MDA-MB-231 (myoepithelial cells substitute) and epithelial cells when co-cultured with MCF-7 both in vitro and in vivo.

Conclusions

In conclusion, these findings demonstrated that both EMT phenotypes and cancer-associated myoepithelial cells may have an impact on the development of invasive breast cancer.

The Regulation of NFE2L2 (NRF2) Signalling and Epithelial-to-Mesenchymal Transition in Age-Related Macular Degeneration Pathology

Age-related macular degeneration (AMD) is a mounting cause of loss of sight in the elderly in the developed countries, a trend enhanced by the continual ageing of the population. AMD is a multifactorial and only partly understood, malady. Unfortunately, there is no effective treatment for most AMD patients. It is known that oxidative stress (OS) damages the retinal pigment epithelium (RPE) and contributes to the progression of AMD. We review here the potential importance of two OS-related cellular systems in relation to AMD. First, the nuclear factor erythroid 2-related factor 2 (NFE2L2; NRF2)-mediated OS response signalling pathway is important in the prevention of oxidative damage and a failure of this system could be critical in the development of AMD. Second, epithelial-to-mesenchymal transition (EMT) represents a change in the cellular phenotype, which ultimately leads to the fibrosis encountered in RPE, a characteristic of AMD. Many of the pathways triggering EMT are promoted by OS. The possible interconnections between these two signalling routes are discussed here. From a broader perspective, the control of NFE2L2 and EMT as ways of preventing OS-derived cellular damage could be potentially valuable in the therapy of AMD.

Addiction of mesenchymal phenotypes on the FGF/FGFR axis in oral squamous cell carcinoma cells

The epithelial–mesenchymal transition (EMT) is a crucial morphological event that occurs during epithelial tumor progression. ZEB1/2 are EMT transcription factors that are positively correlated with EMT phenotypes and breast cancer aggressiveness. ZEB1/2 regulate the alternative splicing and hence isoform switching of fibroblast growth factor receptors (FGFRs) by repressing the epithelial splicing regulatory proteins, ESRP1 and ESRP2. Here, we show that the mesenchymal-like phenotypes of oral squamous cell carcinoma (OSCC) cells are dependent on autocrine FGF–FGFR signaling. Mesenchymal-like OSCC cells express low levels of ESRP1/2 and high levels of ZEB1/2, resulting in constitutive expression of the IIIc-isoform of FGFR, FGFR(IIIc). By contrast, epithelial-like OSCC cells showed opposite expression profiles for these proteins and constitutive expression of the IIIb-isoform of FGFR2, FGFR2(IIIb). Importantly, ERK1/2 was constitutively phosphorylated through FGFR1(IIIc), which was activated by factors secreted autonomously by mesenchymal-like OSCC cells and involved in sustained high-level expression of ZEB1. Antagonizing FGFR1 with either inhibitors or siRNAs considerably repressed ZEB1 expression and restored epithelial-like traits. Therefore, autocrine FGF–FGFR(IIIc) signaling appears to be responsible for sustaining ZEB1/2 at high levels and the EMT phenotype in OSCC cells.

Crosstalk between autophagy and epithelial-mesenchymal transition and its application in cancer therapy

Autophagy is a highly conserved catabolic process that mediates degradation of pernicious or dysfunctional cellular components, such as invasive pathogens, senescent proteins, and organelles. It can promote or suppress tumor development, so it is a “double-edged sword” in tumors that depends on the cell and tissue types and the stages of tumor. The epithelial-mesenchymal transition (EMT) is a complex biological trans-differentiation process that allows epithelial cells to transiently obtain mesenchymal features, including motility and metastatic potential. EMT is considered as an important contributor to the invasion and metastasis of cancers. Thus, clarifying the crosstalk between autophagy and EMT will provide novel targets for cancer therapy. It was reported that EMT-related signal pathways have an impact on autophagy; conversely, autophagy activation can suppress or strengthen EMT by regulating various signaling pathways. On one hand, autophagy activation provides energy and basic nutrients for EMT during metastatic spreading, which assists cells to survive in stressful environmental and intracellular conditions. On the other hand, autophagy, acting as a cancer-suppressive function, is inclined to hinder metastasis by selectively down-regulating critical transcription factors of EMT in the early phases. Therefore, the inhibition of EMT by autophagy inhibitors or activators might be a novel strategy that provides thought and enlightenment for the treatment of cancer. In this article, we discuss in detail the role of autophagy and EMT in the development of cancers, the regulatory mechanisms between autophagy and EMT, the effects of autophagy inhibition or activation on EMT, and the potential applications in anticancer therapy.

Involvement of partial EMT in cancer progression

The epithelial-mesenchymal transition (EMT) provides an outstanding example of cellular plasticity during embryonic development and cancer progression. During EMT in embryonic development, epithelial cells lose all vestiges of their epithelial origin and acquire a fully mesenchymal phenotype, known as complete EMT, which is typically characterized by a so-called cadherin switch. Conversely, during EMT in cancer progression, cancer cells that originate from epithelial cells exhibit both mesenchymal and epithelial characteristics, that is the hybrid E/M phenotype in a process known as partial EMT. Partial EMT in cancer cells is thought to enhance their invasive properties, generate circulating tumour cells and cancer stem cells, and promote resistance to anti-cancer drugs. These phenotypic changes are regulated by extracellular matrix components, exosomes and soluble factors, which regulate several transcription factors known as EMT transcription factors. In this review, I summarize our current understanding of the EMT program during cancer progression.

Down-regulation of long non-coding RNA GAS5-AS1 and its prognostic and diagnostic significance in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the most common solid tumor in global range, with high degree of malignancy and poor prognosis. But the relationship between the expression of GAS5-AS1 and HCC is not documented. This study aimed to profile GAS5-AS1 expression signature and then to explore its clinical significance in HCC.

METHODS

Quantitative real-time PCR (RT-qPCR) was performed to detect the expression of GAS5-AS1 in 83 pairs of HCC surgical tissues and adjacent normal liver tissues. We also performed RT-qPCR on plasma samples of 156 patients and 58 healthy controls.

RESULTS

We found that GAS5-AS1 was down-regulated in HCC tissues (P< 0.01). Correlation analysis showed that the expression of GAS5-AS1 was notably associated with differentiation (High/Moderate vs Low, P= 0.031), tumor-node-metastasis (TNM) stage (I∼II vs III∼IV, P= 0.020) and glucose levels (< 6.2 vs≧ 6.2, P= 0.047) in HCC patients. The overall survival analysis showed that patients with lower GAS5-AS1 expression had a relatively poor prognosis. Univariate and multivariate analysis elaborated that GAS5-AS1 was an independent prognostic factor for HCC patients. The area under the ROC (AUCROC) demonstrated that GAS5-AS1 presented a high accuracy (AUC = 0.824, 95% CI: 0.741-0.906) for distinguishing HCC from the cirrhosis. When differentiating HCC cases with AFP < 200 ng/ml from the cirrhosis and hepatitis B whose AFP levels were also below 200 ng/ml, GAS5-AS1 had the high sensitivity (89.5%, 89.5%, respectively).

CONCLUSIONS

GAS5-AS1 could be considered as a potential prognostic and diagnostic marker in HCC. However, the potential clinical application value of GAS5-AS1 still needs to be further illustrated.

Circular RNA hsa_circ_0008305 (circPTK2) inhibits TGF-β-induced epithelial-mesenchymal transition and metastasis by controlling TIF1γ in non-small cell lung cancer

BACKGROUND

TGF-β promotes tumor invasion and metastasis through inducing epithelial-mesenchymal transition (EMT) in non-small cell lung cancer (NSCLC). Circular RNAs (circRNAs) are recognized as functional non-coding RNAs involved in human cancers. However, whether and how circRNAs contribute to TGF-β-induced EMT and metastasis in NSCLC remain vague. Here, we investigated the regulation and function of Circular RNA hsa_circ_0008305 (circPTK2) in TGF-β-induced EMT and tumor metastasis, as well as a link between circPTK2 and transcriptional intermediary factor 1 γ (TIF1γ) in NSCLC.

METHODS

Circular RNAs were determined by human circRNA Array analysis, real-time quantitative reverse transcriptase PCR and northern blot. Luciferase reporter, RNA-binding protein immunoprecipitation (RIP), RNA pull-down and fluorescence in situ hybridization (FISH) assays were employed to test the interaction between circPTK2 and miR-429/miR-200b-3p. Ectopic overexpression and siRNA-mediated knockdown of circPTK2, TGF-β-induced EMT, Transwell migration and invasion in vitro, and in vivo experiment of metastasis were used to evaluate the function of circPTK2. Transcription and prognosis analyses were done in public databases.

RESULTS

CircPTK2 and TIF1γ were significantly down-regulated in NSCLC cells undergoing EMT induced by TGF-β. CircPTK2 overexpression augmented TIF1γ expression, inhibited TGF-β-induced EMT and NSCLC cell invasion, whereas circPTK2 knockdown had the opposite effects. CircPTK2 functions as a sponge of miR-429/miR-200b-3p, and miR-429/miR-200b-3p promote TGF-β-induced EMT and NSCLC cell invasion by targeting TIF1γ. CircPTK2 overexpression inhibited the invasion-promoting phenotype of endogenous miR-429/miR-200b-3p in NSCLC cells in response to TGF-β. CircPTK2 overexpression significantly decreased the expression of Snail, an important downstream transcriptional activator of TGF-β/Smad signaling. In an in vivo experiment of metastasis, circPTK2 overexpression suppressed NSCLC cell metastasis. Moreover, circPTK2 expression was dramatically down-regulated and positively correlated with TIF1γ expression in human NSCLC tissues. Especially, circPTK2 was significantly lower in metastatic NSCLC tissues than non-metastatic counterparts.

CONCLUSION

Our findings show that circPTK2 (hsa_circ_0008305) inhibits TGF-β-induced EMT and metastasis by controlling TIF1γ in NSCLC, revealing a novel mechanism by which circRNA regulates TGF-β-induced EMT and tumor metastasis, and suggesting that circPTK2 overexpression could provide a therapeutic strategy for advanced NSCLC.

TGF-β Signaling in Lung Health and Disease

Transforming growth factor (TGF)-β is an evolutionarily conserved pleiotropic factor that regulates a myriad of biological processes including development, tissue regeneration, immune responses, and tumorigenesis. TGF-β is necessary for lung organogenesis and homeostasis as evidenced by genetically engineered mouse models. TGF-β is crucial for epithelial-mesenchymal interactions during lung branching morphogenesis and alveolarization. Expression and activation of the three TGF-β ligand isoforms in the lungs are temporally and spatially regulated by multiple mechanisms. The lungs are structurally exposed to extrinsic stimuli and pathogens, and are susceptible to inflammation, allergic reactions, and carcinogenesis. Upregulation of TGF-β ligands is observed in major pulmonary diseases, including pulmonary fibrosis, emphysema, bronchial asthma, and lung cancer. TGF-β regulates multiple cellular processes such as growth suppression of epithelial cells, alveolar epithelial cell differentiation, fibroblast activation, and extracellular matrix organization. These effects are closely associated with tissue remodeling in pulmonary fibrosis and emphysema. TGF-β is also central to T cell homeostasis and is deeply involved in asthmatic airway inflammation. TGF-β is the most potent inducer of epithelial-mesenchymal transition in non-small cell lung cancer cells and is pivotal to the development of tumor-promoting microenvironment in the lung cancer tissue. This review summarizes and integrates the current knowledge of TGF-β signaling relevant to lung health and disease.

Overexpression of GRB2 Enhances Epithelial to Mesenchymal Transition of A549 Cells by Upregulating SNAIL Expression

GRB2 is an adaptor protein which interacts with phosphorylated TGF-β receptor and is critical for mammary tumour growth. We found that TGF-β1-induced EMT increased GRB2 expression in A549 cells (non-small cell lung cancer). Overexpression of GRB2 (A549^GRB2) enhanced cell invasion while knocking down GRB2 (A549^GRB2KD) reduced cell migration and invasion, probably due to increased vinculin and reduced Paxillin patches in A549^GRB2KD cell. TGF-β1-induced EMT was more pronounced in A549^GRB2 cells and attenuated in A549^GRB2KD cells. This could be due to the reduced expression of E-cadherin in A549^GRB2 and increased expression of E-cadherin in A549^GRB2KD cells, even before TGF-β1 stimulation. Expression of SNAIL was elevated in A549^GRB2 cells and was further enhanced by TGF-β1 stimulation, suggesting that GRB2 down-regulates E-cadherin by enhancing the expression of SNAIL. The N-SH3 domain of GRB2 was critical for suppressing E-cadherin expression, while the C-SH3 domain of GRB2 mediating interaction with proteins such as N-WASP was critical for promoting invasion, and the SH2 domain was critical for suppressing E-cadherin expression and invasion. Thus, our data suggests that GRB2 enhances EMT by suppressing E-cadherin expression and promoting invasion probably through N-WASP to promote metastasis.

Baicalein suppress EMT of breast cancer by mediating tumor-associated macrophages polarization

Tumor associated macrophages (TAMs) are the main infiltrating component in the tumor microenvironment and play an important role in cancer progression. Baicalein has a wide range of pharmacological properties. This study explores the potential effect of baicalein on macrophages polarization and epithelial-mesenchymal transition (EMT) of breast cancer. Co-culture system was established to evaluate the interaction between TAMs and breast cancer cells. Then the role of baicalein in modulating TAMs function was assessed. Finally, breast cancer mouse model was established to study the underlying mechanism. In vitro experiments showed that co-culture with M2 macrophages significantly enhanced EMT of both MDA-MB-231 and MCF-7 breast cancer cells. Baicalein could regulate polarization of M2 and attenuate TGF-β1 secretion. In vivo experiments showed that compared with the MDA-MB-231 + M2 group, tumor growth and metastasis of baicalein + MDA-MB-231 + M2 group was significantly inhibited, with smaller tumor size and decreased lung metastasis lesions. Our findings suggest that the regulation of TAMs may be a novel mechanism underlying the anti-tumor effects of baicalein in breast cancer.

Reciprocal expression of Slug and Snail in human oral cancer cells

Snail, also called Snai1, is a key regulator of EMT. Snail plays crucial roles in cancer progression, including resistance to anti-tumor drugs and invasion by various cancer cells. Slug, also known as Snai2, is also involved in the aggravation of certain tumors. In this study, we examined the roles of Slug in human oral squamous cell carcinoma (OSCC) cells. Slug is highly expressed in these cells, and Slug siRNA effectively represses anti-tumor drug resistance and invasive properties. In addition, transforming growth factor (TGF)-β upregulates the expression of Snail and Slug and promotes resistance to anti-tumor drugs in OSCC cells. Surprisingly, Slug siRNA appears to upregulate Snail expression considerably in OSCC cells. Snail siRNA also appears to upregulate Slug expression. Thus, either Slug or Snail siRNA alone partially mitigates malignant phenotypes in the presence of TGF-β, whereas both Slug and Snail siRNAs together dramatically suppress them. Therefore, Slug and Snail in tandem, but not alone, are potential therapeutic targets for nucleic acid medicines to treat oral cancer.