Down-regulation of TIMP2 by HIF-1α/miR-210/HIF-3α regulatory feedback circuit enhances cancer metastasis in hepatocellular carcinoma

Regulation of the HIF switch in human endothelial and cancer cells

Hypoxia-inducible factors (HIFs) are transcription factors that reprogram the transcriptome for cells to survive hypoxic insults and oxidative stress. They are important during embryonic development and reprogram the cells to utilize glycolysis when the oxygen levels are extremely low. This metabolic change facilitates normal cell survival as well as cancer cell survival. The key feature in survival is the transition between acute hypoxia and chronic hypoxia, and this is regulated by the transition between HIF-1 expression and HIF-2/HIF-3 expression. This transition is observed in many human cancers and endothelial cells and referred to as the HIF Switch. Here we discuss the mechanisms involved in the HIF Switch in human endothelial and cancer cells which include mRNA and protein levels of the alpha chains of the HIFs. A major continuing effort in this field is directed towards determining the differences between normal and tumor cell utilization of this important pathway, and how this could lead to potential therapeutic approaches.

microRNAs, oxidative stress, and genotoxicity as the main inducers in the pathobiology of cancer development

Cancer is one of the most serious leading causes of death in the world. Many eclectic factors are involved in cancer progression including genetic and epigenetic alongside environmental ones. In this account, the performance and fluctuations of microRNAs are significant in cancer diagnosis and treatment, particularly as diagnostic biomarkers in oncology. So, microRNAs manage and control the gene expression after transcription by mRNA degradation, or also they can inhibit their translation. Conspicuously, these molecular structures take part in controlling the cellular, physiological and pathological functions, which many of them can accomplish as tumor inhibitors or oncogenes. Relatively, Oxidative stress is defined as the inequality between the creation of reactive oxygen species (ROS) and the body's ability to detoxify the reactive mediators or repair the resulting injury. ROS and microRNAs have been recognized as main cancer promoters and possible treatment targets. Importantly, genotoxicity has been established as the primary reason for many diseases as well as several malignancies. The procedures have no obvious link with mutagenicity and influence the organization, accuracy of the information, or fragmentation of DNA. Conclusively, mutations in these patterns can lead to carcinogenesis. In this review article, we report the impressive and practical roles of microRNAs, oxidative stress, and genotoxicity in the pathobiology of cancer development in conjunction with their importance as reliable cancer biomarkers and their association with circulating miRNA, exosomes and exosomal miRNAs, RNA remodeling, DNA methylation, and other molecular elements in oncology.

Regulation of Cancer-Associated miRNAs Expression under Hypoxic Conditions

Solid tumors frequently experience hypoxia or low O2 levels. In these conditions, hypoxia-inducible factor 1 alpha (HIF-1α) is activated and acts as a transcription factor that regulates cancer cell adaptation to O2 and nutrient deprivation. HIF-1α controls gene expression associated with various signaling pathways that promote cancer cell proliferation and survival. MicroRNAs (miRNAs) are 22-nucleotide noncoding RNAs that play a role in various biological processes essential for cancer progression. This review presents an overview of how hypoxia regulates the expression of multiple miRNAs in the progression of cancer cells.

Hypoxia-induced miR-210-3p expression in lung adenocarcinoma potentiates tumor development by regulating CCL2 mediated monocyte infiltration

In most cancers, tumor hypoxia downregulates the expression of C-C motif chemokine 2 (CCL2), and this downregulation has been implicated in monocyte infiltration and tumor progression; however, the molecular mechanism is not yet clear. We compared noncancerous and lung-adenocarcinoma human samples for hypoxia-inducible factor 1-alpha (HIF-1A), microRNA-210-3p (mir-210-3p), and CCL2 levels. Mechanistic studies were performed on lung adenocarcinoma cell lines and 3D tumor spheroids to understand the role of hypoxia-induced miR-210-3p in the regulation of CCL2 expression and macrophage polarization. HIF-1Α stabilization increases miR-210-3p levels in lung adenocarcinoma and impairs monocyte infiltration by inhibiting CCL2 expression. Mechanistically, miR-210-3p directly binds to the 3'untranslated region (UTR) of CCL2 mRNA and silences it. Suppressing miR-210-3p substantially downregulates the effect of hypoxia on CCL2 expression. Monocyte migration is significantly hampered in miR-210-3p mimic-transfected HIF-1A silenced cancer cells. In contrast, inhibition of miR-210-3p in HIF-1A-overexpressed cells markedly restored monocyte migration, highlighting a direct link between the miR-210-3p level and tumor monocyte burden. Moreover, miR-210-3p inhibition in 3D tumor spheroids promotes monocyte recruitment and skewing towards an antitumor M1 phenotype. Anti-hsa-miR-210-3p-locked nucleic acid (LNA) delivery in a lung tumor xenograft zebrafish model caused tumor regression, suggesting that miR-210-3p could be a promising target for immunomodulatory therapeutic strategies against lung adenocarcinoma.

HIF-1α/MMP-9 Axis Is Required in the Early Phases of Skeletal Myoblast Differentiation under Normoxia Condition In Vitro

Hypoxia-inducible factor (HIF)-1α represents an oxygen-sensitive subunit of HIF transcriptional factor, which is usually degraded in normoxia and stabilized in hypoxia to regulate several target gene expressions. Nevertheless, in the skeletal muscle satellite stem cells (SCs), an oxygen level-independent regulation of HIF-1α has been observed. Although HIF-1α has been highlighted as a SC function regulator, its spatio-temporal expression and role during myogenic progression remain controversial. Herein, using biomolecular, biochemical, morphological and electrophysiological analyses, we analyzed HIF-1α expression, localization and role in differentiating murine C2C12 myoblasts and SCs under normoxia. In addition, we evaluated the role of matrix metalloproteinase (MMP)-9 as an HIF-1α effector, considering that MMP-9 is involved in myogenesis and is an HIF-1α target in different cell types. HIF-1α expression increased after 24/48 h of differentiating culture and tended to decline after 72 h/5 days. Committed and proliferating mononuclear myoblasts exhibited nuclear HIF-1α expression. Differently, the more differentiated elongated and parallel-aligned cells, which are likely ready to fuse with each other, show a mainly cytoplasmic localization of the factor. Multinucleated myotubes displayed both nuclear and cytoplasmic HIF-1α expression. The MMP-9 and MyoD (myogenic activation marker) expression synchronized with that of HIF-1α, increasing after 24 h of differentiation. By means of silencing HIF-1α and MMP-9 by short-interfering RNA and MMP-9 pharmacological inhibition, this study unraveled MMP-9's role as an HIF-1α downstream effector and the fact that the HIF-1α/MMP-9 axis is essential in morpho-functional cell myogenic commitment.

Alleviating hypoxia to improve cancer immunotherapy

Tumor hypoxia resulting from abnormal and dysfunctional tumor vascular network poses a substantial obstacle to immunotherapy. In fact, hypoxia creates an immunosuppressive tumor microenvironment (TME) through promoting angiogenesis, metabolic reprogramming, extracellular matrix remodeling, epithelial-mesenchymal transition (EMT), p53 inactivation, and immune evasion. Vascular normalization, a strategy aimed at restoring the structure and function of tumor blood vessels, has been shown to improve oxygen delivery and reverse hypoxia-induced signaling pathways, thus alleviates hypoxia and potentiates cancer immunotherapy. In this review, we discuss the mechanisms of tumor tissue hypoxia and its impacts on immune cells and cancer immunotherapy, as well as the approaches to induce tumor vascular normalization. We also summarize the evidence supporting the use of vascular normalization in combination with cancer immunotherapy, and highlight the challenges and future directions of this overlooked important field. By targeting the fundamental problem of tumor hypoxia, vascular normalization proposes a promising strategy to enhance the efficacy of cancer immunotherapy and improve clinical outcomes for cancer patients.

The role of noncoding RNAs in the tumor microenvironment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the leading fatal malignancy worldwide. The tumor microenvironment (TME) can affect the survival, proliferation, migration, and even dormancy of cancer cells. Hypoxia is an important component of the TME, and hypoxia-inducible factor-1α (HIF-1α) is the most important transcriptional regulator. Noncoding RNAs (ncRNAs), including microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), comprise a large part of the human transcriptome and play an important role in regulating the tumorigenesis of HCC. This review discusses the role of ncRNAs in hepatocarcinogenesis, epithelial-mesenchymal transition (EMT), and angiogenesis in a hypoxic microenvironment, as well as the interactions between ncRNAs and key components of the TME. It further discusses their use as biomarkers and the potential clinical value of drugs, as well as the challenges faced in the future.

Understanding crosstalk of organ tropism, tumor microenvironment and noncoding RNAs in breast cancer metastasis

Cancer metastasis is one of the major clinical challenges worldwide due to limited existing effective treatments. Metastasis roots from the host organ of origin and gradually migrates to different regional and distant organs. In different breast cancer subtypes, different organs like bones, liver, lungs and brain are targeted by the metastatic tumor cells. Cancer renders mortality to their respective metastasizing sites like bones, brain, liver, and lungs. Metastatic breast cancers are best treated and managed if detected at an early stage. Metastasis is regulated by various molecular activators and suppressors. The conventional theory of 'seed and soil' states that metastatic tumor cells move to tumor microenvironment that has favorable conditions like blood flow for them to grow just like seeds grows when planted in fertile land. Additionally, different coding as well as non-coding RNAs play a very significant role in the process of metastasis by modulating their expression levels leading to a crosstalk of various tumorigenic cascades. Treatments for metastasis is also very critical in controlling this lethal process. Detecting breast cancer metastasis at an early stage is crucial for managing and predicting metastatic progression. In this review, we have compiled several factors that can be targeted to manage the onset and gradual stages of breast cancer metastasis.

Travelling under pressure - hypoxia and shear stress in the metastatic journey

Cancer cell invasion, intravasation and survival in the bloodstream are early steps of the metastatic process, pivotal to enabling the spread of cancer to distant tissues. Circulating tumor cells (CTCs) represent a highly selected subpopulation of cancer cells that tamed these critical steps, and a better understanding of their biology and driving molecular principles may facilitate the development of novel tools to prevent metastasis. Here, we describe key research advances in this field, aiming at describing early metastasis-related processes such as collective invasion, shedding, and survival of CTCs in the bloodstream, paying particular attention to microenvironmental factors like hypoxia and mechanical stress, considered as important influencers of the metastatic journey.

Dznep, a histone modification inhibitor, inhibits HIF1α binding to TIMP2 gene and suppresses TIMP2 expression under hypoxia

Epidemiological studies have shown that patients who recovered from acute kidney injury (AKI) may subsequently develop chronic kidney disease (CKD). AKI is primarily caused by renal hypoxia, and it causes epigenetic alterations, known as hypoxic memory. 3-Deazaneplanocin A (Dznep), an inhibitor of histone modification, suppresses renal fibrosis and the expression of tissue inhibitor of metalloproteinases-2 (TIMP2), a profibrotic factor, in mouse ischemia-reperfusion models. The current study investigated the epigenetic regulation of TIMP2 in human kidney 2 (HK-2) cells. The expression of TIMP2 was upregulated in HK-2 cells under hypoxic conditions and was suppressed by Dznep. ChIP-qPCR showed that Dznep reduced the amount of H3K4me3 at the promoter region of the TIMP2 gene under hypoxic condition. Formaldehyde-assisted isolation of regulatory elements-qPCR of the TIMP2 gene showed that Dznep reduced open chromatin area. In addition, based on ChIP-qPCR of hypoxia-inducible factor 1 alpha (HIF1α), Dznep inhibited the binding of HIF1α to the TIMP2 gene under hypoxic conditions. The reporter assays for the binding region of HIF1α showed enhanced transcriptional activity by hypoxia. Dznep suppresses the expression of TIMP2 under hypoxic conditions by inhibiting the binding of HIF1α to the TIMP2 gene.

IL-17 induces non-small cell lung cancer metastasis via GCN5-dependent SOX4 acetylation enhancing MMP9 gene transcription and expression

Interleukin-17 (IL-17), a potent proinflammatory cytokine, can trigger the metastasis of non-small cell lung cancer (NSCLC). However, the underlying mechanism involved in IL-17-induced NSCLC cell metastasis remains unclear. In this study, we found that not only the expression of IL-17, IL-17RA, and/or general control nonrepressed protein 5 (GCN5), SRY-related HMG-BOX gene 4 (SOX4), and matrix metalloproteinase 9 (MMP9) was increased in the NSCLC tissues and in the IL-17-stimulated NSCLC cells, but also IL-17 treatment could enhance NSCLC cell migration and invasion. Further mechanism exploration revealed that IL-17-upregulated GCN5 and SOX4 could bind to the same region (-915 to -712 nt) of downstream MMP9 gene promoter driving its gene transcription. In the process, GCN5 could mediate SOX4 acetylation at lysine 118 (K118, a newly identified site) boosting MMP9 gene expression as well as cell migration and invasion. Moreover, the SOX4 acetylation or MMP9 induction and metastatic nodule number in the lung tissues of the BALB/c nude mice inoculated with the NSCLC cells stably infected by corresponding LV-shGCN5 or LV-shSOX4, LV-shMMP9 plus IL-17 incubation were markedly reduced. Overall, our findings implicate that NSCLC metastasis is closely associated with IL-17-GCN5-SOX4-MMP9 axis.

The differential cancer growth associated with anaesthetics in a cancer xenograft model of mice: mechanisms and implications of postoperative cancer recurrence

Anaesthetics may modify colorectal cancer cell biology which potentially affects long-term survival. This study aims to compare propofol and sevoflurane regarding with the direct anaesthetic effects on cancer malignancy and the indirect effects on host immunity in a cancer xenograft mode of mice. Cultured colon cancer cell (Caco-2) was injected subcutaneously to nude mice (day 1). Mice were exposed to either 1.5% sevoflurane for 1.5 h or propofol (20 μg g-1; ip injection) with or without 4 μg g-1 lipopolysaccharide (LPS; ip) from days 15 to 17, compared with those without anaesthetic exposure as controls. The clinical endpoints including tumour volumes over 70 mm3 were closely monitored up to day 28. Tumour samples from the other cohorts were collected on day 18 for PCR array, qRT-PCR, western blotting and immunofluorescent assessment. Propofol treatment reduced tumour size (mean ± SD; 23.0 ± 6.2mm3) when compared to sevoflurane (36.0 ± 0.3mm3) (p = 0.008) or control (23.6 ± 4.7mm3). Propofol decreased hypoxia inducible factor 1α (HIF1α), interleukin 1β (IL1β), and hepatocyte growth factor (HGF) gene expressions and increased tissue inhibitor of metalloproteinases 2 (TIMP-2) gene and protein expression in comparison to sevoflurane in the tumour tissue. LPS suppressed tumour growth in any conditions whilst increased TIMP-2 and anti-cancer neutrophil marker expressions and decreased macrophage marker expressions compared to those in the LPS-untreated groups. Our data indicated that sevoflurane increased cancer development when compared with propofol in vivo under non-surgical condition. Anaesthetics tested in this study did not alter the effects of LPS as an immune modulator in changing immunocyte phenotype and suppressing cancer development.

CPEB2 Suppresses Hepatocellular Carcinoma Epithelial-Mesenchymal Transition and Metastasis through Regulating the HIF-1α/miR-210-3p/CPEB2 Axis

Hepatocellular carcinoma (HCC) is a prevalent and high-mortality cancer worldwide, and its complexity necessitates novel strategies for drug selection and design. Current approaches primarily focus on reducing gene expression, while promoting gene overexpression remains a challenge. In this work, we studied the effect of cytoplasmic polyadenylation element binding protein 2 (CPEB2) in HCC by constructing tissue microarrays (TAMs) from 90 HCC cases and corresponding para-cancerous tissues. Our analysis showed that CPEB2 expression was significantly reduced in HCC tissues, and its low expression was associated with a higher recurrence risk and poorer prognosis in patients with head and neck cancer. CPEB2 was found to regulate HCC epithelial-mesenchymal transition (EMT) and metastasis through the HIF-1α/miR-210-3p/CPEB2 feedback circuit. Using the RNA binding protein immunoprecipitation (RIP) assay, we demonstrated that miR-210 directly governs the expression of CPEB2. The inverse relationship between CPEB2 expression and miR-210-3p in HCC tissues suggested that this regulatory mechanism is directly linked to HCC metastasis, EMT, and clinical outcomes. Moreover, utilizing the SM2miR database, we identified drugs that can decrease miR-210-3p expression, consequently increasing CPEB2 expression and providing new insights for drug development. In conclusion, our findings illustrated a novel HIF-1α/miR-210-3p/CPEB2 regulatory signaling pathway in HCC and highlighted the potential of enhancing CPEB2 expression through targeting miR-210-3p as a novel predictive biomarker and therapeutic strategy in HCC, as it is modulated by the HIF-1α/miR-210-3p/CPEB2 feedback circuit.

miR-210 promotes hepatocellular carcinoma progression by modulating macrophage autophagy through PI3K/AKT/mTOR signaling

BACKGROUND

Tumor-associated macrophages (TAMs) play an important role in tumor development. Increasing research suggests that miR-210 may promote the progression of tumor virulence, but whether its pro-carcinogenic effect in primary hepatocellular carcinoma (HCC) is via an action on M2 macrophages has not been examined.

METHODS

Differentiation of THP-1 monocytes into M2-polarized macrophages was induced with phorbol myristate acetate (PMA) and IL-4, IL-13. M2 macrophages were transfected with miR-210 mimics or miR-210 inhibitors. Flow cytometry was used to identify macrophage-related markers and apoptosis levels. The autophagy level of M2 macrophages, expression of PI3K/AKT/mTOR signaling pathway-related mRNAs and protein were detected by qRT-PCR and Western blot. HepG2 and MHCC-97H HCC cell lines were cultured with M2 macrophages conditioned medium to explore the effects of M2 macrophage-derived miR-210 on the proliferation, migration, invasion and apoptosis of HCC cells.

RESULTS

qRT-PCR showed increased expression of miR-210 in M2 macrophages. Autophagy-related gene and protein expression was enhanced in M2 macrophages transfected with miR-210 mimics, while apoptosis-related proteins were decreased. MDC staining and transmission electron microscopy observed the accumulation of MDC-labeled vesicles and autophagosomes in M2 macrophages in the miR-210 mimic group. The expression of PI3K/AKT/mTOR signaling pathway in M2 macrophages was reduced in miR-210 mimic group. HCC cells co-cultured with M2 macrophages transfected with miR-210 mimics exhibited enhanced proliferation and invasive ability as compared to the control group, while apoptosis levels were reduced. Moreover, promoting or inhibiting autophagy could enhance or abolish the above observed biological effects, respectively.

CONCLUSIONS

miR-210 can promote autophagy of M2 macrophages via PI3K/AKT/mTOR signaling pathway. M2 macrophage-derived miR-210 promotes the malignant progression of HCC via autophagy, suggesting that macrophage autophagy may serve as a new therapeutic target for HCC, and targeting miR-210 may reset the effect of M2 macrophages on HCC.

Micro RNA210 expression in pregnancies with preeclampsia

Preeclampsia is one of the major causes of perinatal mortality and morbidity even in developed countries, the aetiology of which is not yet understood completely. In recent times, mi RNAs have gained prominence as regulators of the expressions of their target genes in health and pathological condition. mi RNA210, one of the important hypoxamirs, is reported to be a regulator of many cellular mechanisms including cell division, differentiation, apoptosis, cell cycle regulation, mitochondrial function, metabolism etc. Since hypoxia is the microenvironment that prevailed in preeclampsia it is worth full to see the expression pattern of mi RNA 210 as an attempt to unearth the preeclampsia pathogenesis. The placental tissue is collected from age-matched control and preeclamptic patients after strictly applying the inclusion and exclusion criteria. The present result shows 2.7 fold-up regulation of miRNA210 in preeclampsia in rt PCR study, the role of which need to be studied further to understand the pathogenesis of preeclampsia.

Clinical application study on miR-98-5p as a prognostic biomarker in hepatocellular carcinoma

BACKGROUND

On the one hand, to investigate the targeted regulation of miR-98-5p on heparin-binding epidermal growth factor-like growth factor (HBEGF) in patients with hepatocellular carcinoma (HCC). On the other hand, elucidate the predictive effect of miR-98-5p combined with magnetic resonance imaging (MRI) data on the clinical prognosis of HCC patients.

METHODS

Serum samples from 98 HCC patients and 54 healthy subjects were selected in order to detect miR-98-5p as well as HBEGF expression levels via real-time quantitative PCR (RT-qPCR). A Luciferase reporter assay was performed to detect the interaction between miR-98-5p and HBEGF gene. The serum levels of IL-2, TNF-α, TGF-β1 and IFN-γ in HCC patients and in the control group (healthy subjects) were measured by enzyme-linked immunosorbent assay (ELISA). In addition, receiver operator characteristic curve (ROC) was utilized to analyze the predictive ability of miR-98-5p combined with HBEGF for HCC. Finally, the survival curves were used to analyze the effect of HBEGF and miR-98-5p on the survival of patients with HCC.

RESULTS

RT-qPCR results showed that the expression level of miR-98-5p was significantly decreased, while HBEGF expression was significantly increased in the serum of HCC patients compared with the control group. Luciferase reporter assay confirmed that miR-98-5p could target and bind HBEGF. Additionally, according to ELISA, IL-2, TNF-α, and TGF-β1 were significantly increased, while IFN-γ was significantly decreased in the serum of HCC patients compared with the control group. The results of ROC indicated that expressive levels of miR-98-5p and HBEGF had a high diagnostic value for HCC. At the same time, the survival curve results indicated high HBEGF expression and low miR-98-5p expression, suggesting a poor prognosis for HCC patients.

CONCLUSION

MiR-98-5p can target the down-regulating HBEGF gene. In addition, miR-98-5p combined with MRI data is of crucial guiding value in assessing the prognosis of patients with HCC in the clinic.

The Biology and Function of Tissue Inhibitor of Metalloproteinase 2 in the Lungs

Tissue inhibitors of matrix metalloproteinases (TIMP) are a family of four endogenous proteins that primarily function to inhibit the activities of proteases such as the matrix metalloproteinases (MMP). Altered MMP/TIMP ratios are frequently observed in several human diseases. During aging and disease progression, the extracellular matrix (ECM) undergoes structural changes in which elastin and collagens serve an essential role. MMPs and TIMPs significantly influence the ECM. Classically, elevated levels of TIMPs are suggested to result in ECM accumulation leading to fibrosis, whereas loss of TIMP responses leads to enhanced matrix proteolysis. Here, we outline the known roles of the most abundant TIMP, TIMP2, in pulmonary diseases but also discuss future perspectives in TIMP2 research that could impact the lungs. TIMP2 directly inhibits MMPs, in particular MMP2, but TIMP2 is also required for the activation of MMP2 through its interaction with MMP14. The protease and antiprotease imbalance of MMPs and TIMPs are extensively studied in diseases but recent discoveries suggest that TIMPs, specifically, TIMP2 could play other roles in aging and inflammation processes.

Lactate drives cellular DNA repair capacity: Role of lactate and related short-chain fatty acids in cervical cancer chemoresistance and viral infection

The characteristic feature of a cancer microenvironment is the presence of a highly elevated concentration of L-lactate in the tumor niche. The lactate-rich environment is also maintained by commensal mucosal microbiota, which has immense potential for affecting cancer cells through its receptoric and epigenetic modes of action. Some of these lactate activities might be associated with the failure of anticancer therapy as a consequence of the drug resistance acquired by cancer cells. Upregulation of cellular DNA repair capacity and enhanced drug efflux are the most important cellular mechanisms that account for ineffective radiotherapy and drug-based therapies. Here, we present the recent scientific knowledge on the role of the HCA1 receptor for lactate and lactate intrinsic activity as an HDAC inhibitor in the development of an anticancer therapy-resistant tumor phenotype, with special focus on cervical cancer cells. In addition, a recent study highlighted the viable role of interactions between mammalian cells and microorganisms in the female reproductive tract and demonstrated an interesting mechanism regulating the efficacy of retroviral transduction through lactate-driven modulation of DNA-PKcs cellular localization. To date, very few studies have focused on the mechanisms of lactate-driven enhancement of DNA repair and upregulation of particular multidrug-resistance proteins in cancer cells with respect to their intracellular regulatory mechanisms triggered by lactate. This review presents the main achievements in the field of lactate impact on cell biology that may promote undesirable alterations in cancer physiology and mitigate retroviral infections.

HIF-3α-Induced miR-630 Expression Promotes Cancer Hallmarks in Cervical Cancer Cells by Forming a Positive Feedback Loop

Purpose. Hypoxia has crucial functions in the development and metastasis of cervical cancer by inducing the expression of numerous genes, including microRNA genes. But we know little about how the hypoxia factors and microRNAs orchestrate to regulate hallmarks of cervical cancer cells. Methods. We conducted RNA sequencing (RNA-seq) and chromatin immunoprecipitation sequencing (ChIP-seq) experiments to investigate the targets of HIF-3α or miR-630. ChIP-qPCR and RT-qPCR were carried out to validate the results of ChIP-seq and RNA-seq. Cellular, molecular, and radiation experiments were conducted to explore the functions of miR-630. Results. In this study, we showed that hypoxia-induced overexpression of HIF-3α increased the expression of dozens of miRNAs, including miR-630. Hypoxia could also directly induce miR-630 expression. ChIP-seq data showed that HIF-3α activates miR-630 expression by directly binding to the promoter of its host gene. Meanwhile, stable overexpression of miR-630 increased the expression of HIF-3α, but repressed the expression of HIF-1α, indicating a positive feedback loop between HIF-3α and miR-630. Consequently, stable overexpression of miR-630 in HeLa cells promotes cancer hallmarks, including radioresistance, inhibition of apoptosis, increased migration and invasion, and EMT-mediated metastasis. Meanwhile, inhibition of miR-630 showed opposite features. Conclusion. Taken together, our findings indicate a novel hypoxia-induced HIF-3α and miR-630 regulatory feedback loop contributing to metastasis and progression of cervical cancer cells and suggest that HIF-3α and miR-630 might act as potential biomarkers and therapeutic targets for cervical cancer in the future.

Link of sorafenib resistance with the tumor microenvironment in hepatocellular carcinoma: Mechanistic insights

Sorafenib, a multi-kinase inhibitor with antiangiogenic, antiproliferative, and proapoptotic properties, is the first-line treatment for patients with late-stage hepatocellular carcinoma (HCC). However, the therapeutic effect remains limited due to sorafenib resistance. Only about 30% of HCC patients respond well to the treatment, and the resistance almost inevitably happens within 6 months. Thus, it is critical to elucidate the underlying mechanisms and identify effective approaches to improve the therapeutic outcome. According to recent studies, tumor microenvironment (TME) and immune escape play critical roles in tumor occurrence, metastasis and anti-cancer drug resistance. The relevant mechanisms were focusing on hypoxia, tumor-associated immune-suppressive cells, and immunosuppressive molecules. In this review, we focus on sorafenib resistance and its relationship with liver cancer immune microenvironment, highlighting the importance of breaking sorafenib resistance in HCC.

Hypoxia-driven metabolic heterogeneity and immune evasive behaviour of gastrointestinal cancers: Elements of a recipe for disaster

Gastrointestinal (GI) cancers refer to a group of malignancies associated with the GI tract (GIT). Like other solid tumors, hypoxic regions consistently feature inside the GI tumor microenvironment (TME) and contribute towards metabolic reprogramming of tumor-resident cells by modulating hypoxia-induced factors. We highlight here how the metabolic crosstalk between cancer cells and immune cells generate immunosuppressive environment inside hypoxic tumors. Given the fluctuating nature of tumor hypoxia, the metabolic fluxes between immune cells and cancer cells change dynamically. These changes alter cellular phenotypes and functions, resulting in the acceleration of cancer progression. These evolved properties of hypoxic tumors make metabolism-targeting monotherapy approaches or immunotherapy-measures unsuccessful. The current review highlights the advantages of combined immunometabolic treatment strategies to target hypoxic GI cancers and also identifies research areas to develop better combinational therapeutics for future.

Preintervention MCP-1 serum levels as an early predictive marker of tumor response in patients with hepatocellular carcinoma undergoing transarterial chemoembolization

Background

Transarterial chemoembolization (TACE) is a widely accepted treatment for unresectable or intermediate-stage hepatocellular carcinoma (HCC). However, response rates to TACE are heterogeneous and it is not fully understood which patients benefit most from TACE therapy in terms of tumor response. To identify the possible predictive roles of the perioperative monocyte chemoattractant protein-1 (MCP-1) levels in patients of HCC treated with TACE.

Methods

Forty patients of HCC receiving TACE were enrolled in a single center prospective observational study. MCP-1 and miR-210 levels were measured in 40 HCC patients at baseline before TACE and compared with 17 healthy controls by immunoassay and reverse transcriptase quantitative polymerase chain reaction (RT-qPCR). Tumor response assessments were taken after TACE treatment 4–6 weeks. Univariate and multivariate analysis were conducted to analyze factors correlated with tumor response in a Logistic regression model. The predictive roles of the involved variables on tumor response in patients with HCC suffering TACE were examined by receiver operating characteristic (ROC) curve analysis.

Results

The serum MCP-1 and miR-210 levels were significantly elevated in HCC patients compared to healthy subjects. Patients with the low preintervention MCP-1 and miR-210 levels attained a higher probability of achieving an objective response (OR) (88.5% vs.42.9%, P=0.007; 76.9% vs. 35.7%, P=0.010, respectively). Pre-TACE MCP-1 level (<816.63 pg/mL) was an independent risk factor associated with OR after TACE by univariate and multivariate analysis while Pre-TACE miR-210 level (<4.43 relative expression) was just positive by univariate analysis. ROC curve analysis showed that a combined index based on those two factors exhibited optimal predictive power of tumor response among all the involved variables (area under the curve =0.823, 95% CI: 0.681–0.965). Additionally, high pre-TACE serum MCP-1 level was correlated with cirrhosis, vascular invasion and Barcelona Clinic Liver Cancer (BCLC) stage. Elevated pre-TACE serum miR-210 level was associated with and BCLC stage.

Conclusions

The study demonstrates that the pre-TACE serum MCP-1 level serves as an effective predictor for tumor response. These findings probably help discriminate HCC patients pre-TACE who specially benefit from TACE regarding OR.

The crosstalk between reactive oxygen species and noncoding RNAs: from cancer code to drug role

Oxidative stress (OS), characterized by the excessive accumulation of reactive oxygen species (ROS), is an emerging hallmark of cancer. Tumorigenesis and development driven by ROS require an aberrant redox homeostasis, that activates onco-signaling and avoids ROS-induced programmed death by orchestrating antioxidant systems. These processes are revealed to closely associate with noncoding RNAs (ncRNAs). On the basis of the available evidence, ncRNAs have been widely identified as multifarious modulators with the involvement of several key redox sensing pathways, such as NF-κB and Nrf2 signaling, therefore potentially becoming effective targets for cancer therapy. Furthermore, the vast majority of ncRNAs with property of easy detected in fluid samples (e.g., blood and urine) facilitate clinicians to monitor redox homeostasis, indicating a novel method for cancer diagnosis. Herein, focusing on carcinoma initiation, metastasis and chemoradiotherapy resistance, we aimed to discuss the ncRNAs-ROS network involved in cancer progression, and the potential clinical application as biomarkers and therapeutic targets.

Exosomes in the hypoxic TME: from release, uptake and biofunctions to clinical applications

Hypoxia is a remarkable trait of the tumor microenvironment (TME). When facing selective pressure, tumor cells show various adaptive characteristics, such as changes in the expression of cancer hallmarks (increased proliferation, suppressed apoptosis, immune evasion, and so on) and more frequent cell communication. Because of the adaptation of cancer cells to hypoxia, exploring the association between cell communication mediators and hypoxia has become increasingly important. Exosomes are important information carriers in cell-to-cell communication. Abundant evidence has proven that hypoxia effects in the TME are mediated by exosomes, with the occasional formation of feedback loops. In this review, we equally focus on the biogenesis and heterogeneity of cancer-derived exosomes and their functions under hypoxia and describe the known and potential mechanism ascribed to exosomes and hypoxia. Notably, we call attention to the size change of hypoxic cancer cell-derived exosomes, a characteristic long neglected, and propose some possible effects of this size change. Finally, jointly considering recent developments in the understanding of exosomes and tumors, we describe noteworthy problems in this field that urgently need to be solved for better research and clinical application.

Knockdown of long noncoding RNA MIAT attenuates cigarette smoke-induced airway remodeling by downregulating miR-29c-3p-HIF3A axis

Chronic obstructive pulmonary disease (COPD) is a global public health issue and is defined as persistent airflow limitation. COPD is a major cause of morbidity and mortality worldwide. Long noncoding RNAs are involved in the course of pulmonary diseases. Here, we revealed that a long noncoding RNA called myocardial-infarction-associated transcript (MIAT) is upregulated in lung tissues of cigarette smoke (CS)-exposed mice. Knockdown of MIAT attenuated CS or CS-extract-induced inflammatory processes, epithelial-mesenchymal transition (EMT), and collagen deposition. Moreover, according to bioinformatic analyses and luciferase reporter assays, MIAT binds to microRNA-29c-3p (miR-29c-3p) and upregulates hypoxia-inducible factor 3 alpha (HIF3A), a target gene of miR-29c-3p. When the MIAT-specific short hairpin RNA and an miR-29c-3p inhibitor were cotransfected into cells, the inhibitor reversed the effects of MIAT knockdown on cell proliferation, apoptosis, inflammation, EMT, and collagen deposition. Overall, these results indicate that MIAT participates in CS-induced EMT and airway remodeling in COPD by upregulating miR-29c-3p-HIF3A axis output, thereby offering a novel promising biomarker for the assessment of COPD exacerbation induced by CS exposure.

miR-17-5p and miR-4443 Promote Esophageal Squamous Cell Carcinoma Development by Targeting TIMP2

Background

Esophageal squamous cell carcinoma (ESCC) is one of the most frequently diagnosed cancers in the world with a high mortality rate. The mechanism about ESCC development and whether miRNAs play a critical role remains unclear and needs carefully elucidated.

Materials and Methods

High-throughput miRNA sequencing was used to identify the different expression miRNAs between the ESCC tissues and paired adjacent normal tissues. Next, both CCK-8, Transwell and apotosis assay were used to evaluate the role of miRNA in ESCCcells. In addition, we used bioinformatic tools to predict the potential target of the miRNAs and verified by Western Blot. The function of miRNA-target network was further identified in xenograft mice model.

Results

In ESCC, we identified two miRNAs, miR-17-5p and miR-4443, were significantly upregulated in ESCC tissues than adjacent normal tissues. TIMP2 was proved to be the direct target of both two miRNAs. The miR-17-5p/4443- TIMP2 axis was shown to promote the tumor progression in vitro and in vivo experiments.

Conclusions

This study highlights two oncomiRs, miR-17-5p and miR-4443, and its potential role in ESCC progression by regulating TIMP2 expression, suggesting miR-17-5p and miR-4443 may serve as a novel molecular target for ESCC treatment.

ESR1 mediated circ_0004018 suppresses angiogenesis in hepatocellular carcinoma via recruiting FUS and stabilizing TIMP2 expression

Angiogenesis has been certified to account for tumor pathobiology. Circular RNAs (circRNAs) have been demonstrated to be involved in angiogenesis-related diseases, including hepatocellular carcinoma (HCC). Nevertheless, the regulatory roles of most circRNAs remain obscure. This study aims to uncover the function of hsa_circ_0004018 on angiogenesis in HCC. Firstly, quantitative real-time RT-PCR (RT-qPCR) analyzed that circ_0004018 was definitely down-regulated in HCC. Western blot analysis was conducted to detect the protein level of fused protein in sarcoma (FUS) and TIMP metallopeptidase inhibitor 2 (TIMP2). Functional assays were carried out to assess the impacts of circ_0004018 on HCC. From the experimental results, we found that overexpression of circ_0004018 significantly inhibited angiogenesis in HCC. The regulatory mechanism of circ_0004018 in HCC was determined by chromatin immunoprecipitation (ChIP), luciferase reporter assays and RNA immunoprecipitation (RIP) assay. Therefore, we proved that estrogen receptor 1 (ESR1) mediated circ_0004018 regulated TIMP2 by recruiting FUS. A series of rescue assays verified that circ_0004018 participated in angiogenesis in HCC via modulating TIMP2. In summary, this paper disclosed that ESR1 activated circ_0004018 inhibited angiogenesis in HCC via binding to FUS and stabilizing TIMP2 expression.

c-Myc-activated intronic miR-210 and lncRNA MIR210HG synergistically promote the metastasis of gastric cancer

The relationship between microRNA (miRNA) and hosting long non-coding RNA (lncRNA) remains unclear. Here, the expression levels of microRNA-210 (miR-210) and hosting lncRNA MIR210HG are significantly increased and positively correlated in gastric cancer (GC). Gain- and loss-of-function studies demonstrate that miR-210 and MIR210HG synergistically promote the migration and invasion of GC cells in vitro. Furthermore, GC sublines simultaneously expressing miR-210 and MIR210HG display synergistic promotion of lung metastasis in vivo. Mechanistically, MIR210HG interacts with DExH-box helicase 9 (DHX9) to increase DHX9/c-Jun complex's occupancy on the promoter of matrix metallopeptidases (MMPs), and thus promotes migration and invasion of GC cells. Additionally, miR-210 directly suppresses the expression of dopamine receptor D5 (DRD5), serine/threonine kinase 24 (STK24) and MAX network transcriptional repressor (MNT), resulting in enhanced migration and invasion. Finally, MYC proto-oncogene (c-Myc) transactivates miR-210 and MIR210HG. Overexpression of miR-210 or/and MIR210HG can rescue the inhibitory effect on the migration and invasion by silencing c-Myc. Moreover, c-Myc inhibitor significantly decreases lung metastasis of GC in vivo. Collectively, our findings identify a novel mechanism, by which c-Myc-activated miR-210 and MIR210HG synergistically promote the metastasis of GC.

HIF-1α promotes the migration and invasion of cancer-associated fibroblasts by miR-210

Metastasis is the major cause of death in colorectal cancer (CRC) patients. Inhibition of metastasis will prolong the survival of patients with CRC. Cancer cells bring their own soil, cancer-associated fibroblasts (CAFs), to metastasize together, promoting the survival and colonization of circulating cancer cells. However, the mechanism by which CAFs metastasize remains unclear. In this study, CAFs were derived from adipose mesenchymal stem cells (MSCs) after co-culture with CRC cell lines. Transwell assays showed that CAFs have stronger migration and invasion abilities than MSCs. In a nude mouse subcutaneous xenograft model, CAFs metastasized from the primary tumour to the lung and promoted the formation of CRC metastases. The expression of HIF-1α was upregulated when MSCs differentiated into CAFs. Inhibition of HIF-1α expression inhibited the migration and invasion of CAFs. Western blot and ChIP assays were used to identify the genes regulated by HIF-1α. HIF-1α regulated the migration and invasion of CAFs by upregulating miR-210 transcription. Bioinformatics analysis and luciferase reporter assays revealed that miR-210 specifically targeted the 3'UTR of VMP1 and regulated its expression. Downregulation of VMP1 enhanced the migration and invasion of CAFs. In vivo, inhibition of miR-210 expression in CAFs reduced the metastasis of CAFs and tumour cells. Therefore, the HIF-1α/miR-210/VMP1 pathway might regulate the migration and invasion of CAFs in CRC. Inhibition of CAF metastasis might reduce CRC metastasis.

Insight into Hypoxia Stemness Control

Recently, the research on stemness and multilineage differentiation mechanisms has greatly increased its value due to the potential therapeutic impact of stem cell-based approaches. Stem cells modulate their self-renewing and differentiation capacities in response to endogenous and/or extrinsic factors that can control stem cell fate. One key factor controlling stem cell phenotype is oxygen (O₂). Several pieces of evidence demonstrated that the complexity of reproducing O₂ physiological tensions and gradients in culture is responsible for defective stem cell behavior in vitro and after transplantation. This evidence is still worsened by considering that stem cells are conventionally incubated under non-physiological air O₂ tension (21%). Therefore, the study of mechanisms and signaling activated at lower O₂ tension, such as those existing under native microenvironments (referred to as hypoxia), represent an effective strategy to define if O₂ is essential in preserving naïve stemness potential as well as in modulating their differentiation. Starting from this premise, the goal of the present review is to report the status of the art about the link existing between hypoxia and stemness providing insight into the factors/molecules involved, to design targeted strategies that, recapitulating naïve O₂ signals, enable towards the therapeutic use of stem cell for tissue engineering and regenerative medicine.

Genome-Wide Analysis Reveals Hypoxic Microenvironment Is Associated With Immunosuppression in Poor Survival of Stage II/III Colorectal Cancer Patients

Background: Hypoxia is associated with a poorer clinical outcome and resistance to chemotherapy in solid tumors; identifying hypoxic-related colorectal cancer (CRC) and revealing its mechanism are important. The aim of this study was to assess hypoxia signature for predicting prognosis and analyze relevant mechanism.

Methods: Patients without chemotherapy were selected for the identification of hypoxia-related genes (HRGs). A total of six independent datasets that included 1,877 CRC patients were divided into a training cohort and two validation cohorts. Functional annotation and analysis were performed to reveal relevant mechanism.

Results: A 12-gene signature was derived, which was prognostic for stage II/III CRC patients in two validation cohorts [TCGA, n = 509, hazard ratio (HR) = 2.14, 95% confidence interval (CI) = 1.18 – 3.89, P = 0.01; metavalidation, n = 590, HR = 2.46, 95% CI = 1.59 – 3.81, P < 0.001]. High hypoxic risk was correlated with worse prognosis in CRC patients without adjuvant chemotherapy (HR = 5.1, 95% CI = 2.51 – 10.35, P < 0.001). After integration with clinical characteristics, hypoxia-related gene signature (HRGS) remained as an independent prognostic factor in multivariate analysis. Furthermore, enrichment analysis found that antitumor immune response was suppressed in the high hypoxic group.

Conclusions: HRGS is a promising system for estimating disease-free survival of stage II/III CRC patients. Hypoxia tumor microenvironment may be via inhibiting immune response to promote chemoresistance in stage II/III CRC patients.

The prognostic and diagnostic value of tissue inhibitor of metalloproteinases gene family and potential function in gastric cancer

Background: Tissue inhibitor of metalloproteinases (TIMP) gene family, including TIMP1, TIMP2, TIMP3 and TIMP4, was found to be correlated with serval cancers. Still the diagnostic and prognostic study of it in gastric cancer (GC) have few reports.

Methods and materials: In this study, the gene expression and clinical data were acquired from the Cancer Gene Atlas (TCGA), function enrichment was used by several databases for verifying known function. Operating characteristic (ROC) curves with area under the curve (AUC) used to assess diagnostic value. Survival analysis and joint-effects survival analysis was performed by the Kaplan-Meier curve. The results were adjusted by cox-regression model. Nomogram is used to directly predict the survival rate for individual GC patient. The potential mechanism for diagnostic and prognostic value was assessed by gene set enrichment analysis (GSEA). Further functions of gene were verified by cell proliferation, migration and invasion assays in human gastric cancer cell line.

Results:TIMP1 was expressed in GC tissue was higher than normal gastric tissue. TIMP3 and TIMP4 have expressed in normal gastric tissue were higher than GC tissue. TIMP1, TIMP3 and TIMP4 have potential diagnostic value (AUC=0.842, 0.729, 0.786 respectively; all P<0.01). Low expression of TIMP2 and TIMP3 associated with favorable overall survival (all P<0.05). TIMP2 and TIMP3, which had significantly affection of prognosis were found having some function such as tRNA processing, cell cycle pathway ncRNA processing. The silencing of TIMP3 could inhibit the migration and invasion of gastric cancer cell.

Conclusion: We analyzed the TIMP gene family in GC, and the prognostic and diagnostic value. TIMP1 and TIMP2 could be used as diagnostic biomarkers in GC. TIMP2 and TIMP3 could be used as potential biomarkers for GC's prognosis.

MicroRNA-210-3p Promotes Chondrogenic Differentiation and Inhibits Adipogenic Differentiation Correlated with HIF-3α Signalling in Bone Marrow Mesenchymal Stem Cells

Cartilage injury of the knee joint is very common. Due to the limited self-healing ability of articular cartilage, osteoarthritis is very likely to occur if left untreated. Bone marrow mesenchymal stem cells (BMMSCs) are widely used in the study of cartilage injury due to their low immunity and good amplification ability, but they still have disadvantages, such as heterogeneous undifferentiated cells. MicroRNAs can regulate the chondrogenic differentiation ability of MSCs by inhibiting or promoting mRNA translation and degradation. In this research, we primarily investigated the effect of microRNA-210-3p (miR-210-3p) on chondrogenic and adipogenic differentiation of BMMSCs in vitro. Our results demonstrate that miR-210-3p promoted chondrogenic differentiation and inhibited adipogenic differentiation of rat BMMSCs, which was related to the HIF-3α signalling pathway. Additionally, miR-210-3p promotes mRNA and protein levels of the chondrogenic expression genes COLII and SOX9 and inhibits mRNA and protein levels of the adipogenic expression genes PPARγ and LPL. Thus, miR-210-3p combined with BMMSCs is a candidate for future clinical applications in cartilage regeneration and could represent a promising new therapeutic target for OA.

Cancer stem cells targets and combined therapies to prevent cancer recurrence

Cancer stem cells (CSCs) control the dynamics of tumorigenesis by self-renewal ability and differentiation potential. These properties contribute towards tumor malignancy, metastasis, cellular heterogeneity, and immune escape, which are regulated by multiple signaling pathways. The CSCs are chemoresistant and cause cancer recurrence, generally recognized as a small side-population that eventually leads to tumor relapse. Despite many treatment options available, none can be considered entirely efficient due to a lack of specificity and dose limitation. This review primarily highlights the processes involved in CSCs development and maintenance. Secondly, the current effective therapies based on stem cells, cell-free therapies that involve exosomes and miRNAs, and photodynamic therapy have been discussed. Also, the inhibitors that specifically target various signaling pathways, which can be used in combination to control CSCs kinetics have been highlighted. Conclusively, this comprehensive review is a detailed study of recently developed novel treatment strategies that will facilitate in coming up with better-targeted approaches against CSCs.

Long non-coding RNA maternally expressed gene 3 affects cell proliferation, apoptosis and migration by targeting the microRNA-9-5p/midkine axis and activating the phosphoinositide-dependent kinase/AKT pathway in hepatocellular carcinoma

Long non-coding RNA (lncRNA) maternally expressed gene 3 (MEG3) is a tumor suppressor in several cancers, such as glioma, prostate cancer and esophageal cancer. However, the role of MEG3 in hepatocellular carcinoma (HCC) and the related molecular mechanisms are not well understood. The present study aimed to determine the biological function of MEG3 in regulating HCC cell viability, apoptosis and migration. In addition, the interaction between MEG3, microRNA (miR)-9-5p and Midkine (MDK), and the activation of the phosphoinositide-dependent kinase (PDK)/AKT pathway in HCC cell line MHCC-97L were examined. Luciferase reporter assays, reverse transcription-quantitative PCR and western blotting were used to determine the interaction between MEG3, miR-9-5p and MDK and the activation of the PDK/AKT pathway. Cell viability was determined by the CCK8 assay and the cell cycle analysis using flow cytometry analysis. Cell apoptosis was examined by flow cytometry analysis and caspase 3/9 activity. Wound healing assays and western blotting were used to investigate cell migration. The present study demonstrated that MEG3 suppressed HCC cell viability and migration, and induced cell apoptosis. In addition, it was also found that MEG3 targets the miR-9-5p/MDK axis and modulates the PDK/AKT pathway in HCC. In conclusion, the findings of the present study demonstrated that lncRNA MEG3 affects HCC cell viability, apoptosis and migration through its targeting of miR-9-5p/MDK and regulation of the PDK/AKT pathway. The MEG3/miR-9-5p/MDK axis may be a potential therapeutic target in HCC.

Construction of a MicroRNA-Based Nomogram for Prediction of Lung Metastasis in Breast Cancer Patients

The lung is one of the most common sites of distant metastasis in breast cancer (BC). Identifying ideal biomarkers to construct a more accurate prediction model than conventional clinical parameters is crucial. MicroRNAs (miRNAs) data and clinicopathological data were acquired from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) database. miR-663, miR-210, miR-17, miR-301a, miR-135b, miR-451, miR-30a, and miR-199a-5p were screened to be highly relevant to lung metastasis (LM) of BC patients. The miRNA-based risk score was developed based on the logistic coefficient of the individual miRNA. Univariate and multivariate logistic regression selected tumor node metastasis (TNM) stage, age at diagnosis, and miRNA-risk score as independent predictive parameters, which were used to construct a nomogram. The Cancer Genome Atlas (TCGA) database was used to validate the signature and nomogram. The predictive performance of the nomogram was compared to that of the TNM stage. The area under the receiver operating characteristics curve (AUC) of the nomogram was higher than that of the TNM stage in all three cohorts (training cohort: 0.774 vs. 0.727; internal validation cohort: 0.763 vs. 0.583; external validation cohort: 0.925 vs. 0.840). The calibration plot of the nomogram showed good agreement between predicted and observed outcomes. The net reclassification improvement (NRI), integrated discrimination improvement (IDI), and decision-curve analysis (DCA) of the nomogram showed that its performances were better than that of the TNM classification system. Functional enrichment analyses suggested several terms with a specific focus on LM. Subgroup analysis showed that miR-30a, miR-135b, and miR-17 have unique roles in lung metastasis of BC. Pan-cancer analysis indicated the significant importance of eight predictive miRNAs in lung metastasis. This study is the first to establish and validate a comprehensive lung metastasis predictive nomogram based on the METABRIC and TCGA databases, which provides a reliable assessment tool for clinicians and aids in appropriate treatment selection.

Invadopodia: A potential target for pancreatic cancer therapy

Dissemination of cancer cells is an intricate multistep process that represents the most deadly aspect of cancer. Cancer cells form F-actin-rich protrusions known as invadopodia to invade surrounding tissues, blood vessels and lymphatics. A number of studies have demonstrated the significant roles of invadopodia in cancer. Therefore, the specific cells and molecules involved in invadopodia activity can provide as therapeutic targets. In this review, we included a thorough overview of studies in invadopodia and discussed their functions in cancer metastasis. We then presented the specific cells and molecules involved in invadopodia activity in pancreatic cancer and analyzed their suitability to be effective therapeutic targets. Currently, drugs targeting invadopodia and relevant clinical trials are negligible. Here, we highlighted the significance of potential drugs and discussed future obstacles in implementing clinical trials. This review presents a new perspective on invadopodia-induced pancreatic cancer metastasis and may prosper the development of targeted therapeutics against pancreatic cancer.

The role of hypoxia in the tumor microenvironment and development of cancer stem cell: a novel approach to developing treatment

Hypoxia is a common feature of solid tumors, and develops because of the rapid growth of the tumor that outstrips the oxygen supply, and impaired blood flow due to the formation of abnormal blood vessels supplying the tumor. It has been reported that tumor hypoxia can: activate angiogenesis, thereby enhancing invasiveness and risk of metastasis; increase survival of tumor, as well as suppress anti-tumor immunity and hamper the therapeutic response. Hypoxia mediates these effects by several potential mechanisms: altering gene expression, the activation of oncogenes, inactivation of suppressor genes, reducing genomic stability and clonal selection. We have reviewed the effects of hypoxia on tumor biology and the possible strategiesto manage the hypoxic tumor microenvironment (TME), highlighting the potential use of cancer stem cells in tumor treatment.

Biology and Clinical Application of Regulatory RNAs in Hepatocellular Carcinoma

Most of the human genome consists of DNA genes that are translated into RNAs but not into proteins. These RNA molecules are named noncoding RNAs (ncRNA). While in the past it was thought that ncRNAs would be redundant without relevant functions, it is now well established that ncRNAs identify a class of regulatory molecules that finely tune cell homeostasis and are deregulated in disease states, including hepatocellular carcinoma (HCC). Of note, the number of ncRNAs within a cell increases progressively, with the complexity of the species indicating their essential role in the maintenance of regulatory networks that affect the intricacy of the organism. ncRNAs have been demonstrated to mediate HCC development and progression by affecting intrinsic cancer cell signaling and crosstalk between malignant cells and the microenvironment. Moreover, ncRNAs hold promise as clinical biomarkers, but further evidence is warranted before their translation and integration within clinical practice.

Mitophagy promotes sorafenib resistance through hypoxia-inducible ATAD3A dependent Axis

BACKGROUND

The identification of novel targets for recovering sorafenib resistance is pivotal for Hepatocellular carcinoma (HCC) patients. Mitophagy is the programmed degradation of mitochondria, and is likely involved in drug resistance of cancer cells. Here, we identified hyperactivated mitophagy is essential for sorafenib resistance, and the mitophagy core regulator gene ATAD3A (ATPase family AAA domain containing 3A) was down regulated in hypoxia induced resistant HCC cells. Blocking mitophagy may restore the sorafenib sensitivity of these cells and provide a new treatment strategy for HCC patients.

METHODS

Hypoxia induced sorafenib resistant cancer cells were established by culturing under 1% O2 with increasing drug treatment. RNA sequencing was conducted in transfecting LM3 cells with sh-ATAD3A lentivirus. Subsequent mechanistic studies were performed in HCC cell lines by manipulating ATAD3A expression isogenically where we evaluated drug sensitivity, molecular signaling events. In vivo study, we investigated the combined treatment effect of sorafenib and miR-210-5P antagomir.

RESULTS

We found a hyperactivated mitophagy regulating by ATAD3A-PINK1/PARKIN axis in hypoxia induced sorafenib resistant HCC cells. Gain- and loss- of ATAD3A were related to hypoxia-induced mitophagy and sorafenib resistance. In addition, ATAD3A is a functional target of miR-210-5p and its oncogenic functions are likely mediated by increased miR-210-5P expression. miR-210-5P was upregulated under hypoxia and participated in regulating sorafenib resistance. In vivo xenograft assay showed that miR-210-5P antagomir combined with sorafenib abrogated the tumorigenic effect of ATAD3A down-regulation in mice.

CONCLUSIONS

Loss of ATAD3A hyperactivates mitophagy which is a core event in hypoxia induced sorafenib resistance in HCC cells. Targeting miR-210-5P-ATAD3A axis is a novel therapeutic target for sorafenib-resistant HCC.

miR-210 Participates in Hepatic Ischemia Reperfusion Injury by Forming a Negative Feedback Loop With SMAD4

BACKGROUND AND AIMS

Hepatic ischemia-reperfusion (IR) injury is a major complication of liver transplantation, resection, and hemorrhagic shock. Hypoxia is a key pathological event associated with IR injury. MicroRNA-210 (miR-210) has been characterized as a micromanager of hypoxia pathway. However, its function and mechanism in hepatic IR injury is unknown.

APPROACH AND RESULTS

In this study, we found miR-210 was induced in liver tissues from patients subjected to IR-related surgeries. In a murine model of hepatic IR, the level of miR-210 was increased in hepatocytes but not in nonparenchymal cells. miR-210 deficiency remarkably alleviated liver injury, cell inflammatory responses, and cell death in a mouse hepatic IR model. In vitro, inhibition of miR-210 decreased hypoxia/reoxygenation (HR)-induced cell apoptosis of primary hepatocytes and LO2 cells, whereas overexpression of miR-210 increased cells apoptosis during HR. Mechanistically, miR-210 directly suppressed mothers against decapentaplegic homolog 4 (SMAD4) expression under normoxia and hypoxia condition by directly binding to the 3' UTR of SMAD4. The pro-apoptotic effect of miR-210 was alleviated by SMAD4, whereas short hairpin SMAD4 abrogated the anti-apoptotic role of miR-210 inhibition in primary hepatocytes. Further studies demonstrated that hypoxia-induced SMAD4 transported into nucleus, in which SMAD4 directly bound to the promoter of miR-210 and transcriptionally induced miR-210, thus forming a negative feedback loop with miR-210.

CONCLUSIONS

Our study implicates a crucial role of miR-210-SMAD4 interaction in hepatic IR-induced cell death and provides a promising therapeutic approach for liver IR injury.

Epigenetic crosstalk between hypoxia and tumor driven by HIF regulation

Hypoxia is the major influence factor in physiological and pathological courses which are mainly mediated by hypoxia-inducible factors (HIFs) in response to low oxygen tensions within solid tumors. Under normoxia, HIF signaling pathway is inhibited due to HIF-α subunits degradation. However, in hypoxic conditions, HIF-α is activated and stabilized, and HIF target genes are successively activated, resulting in a series of tumour-specific activities. The activation of HIFs, including HIF-1α, HIF-2α and HIF-3α, subsequently induce downstream target genes which leads to series of responses, the resulting abnormal processes or metabolites in turn affect HIFs stability. Given its functions in tumors progression, HIFs have been regarded as therapeutic targets for improved treatment efficacy. Epigenetics refers to alterations in gene expression that are stable between cell divisions, and sometimes between generations, but do not involve changes in the underlying DNA sequence of the organism. And with the development of research, epigenetic regulation has been found to play an important role in the development of tumors, which providing accumulating basic or clinical evidences for tumor treatments. Here, given how little has been reported about the overall association between hypoxic tumors and epigenetics, we made a more systematic review from epigenetic perspective in hope of helping others better understand hypoxia or HIF pathway, and providing more established and potential therapeutic strategies in tumors to facilitate epigenetic studies of tumors.

miR-876 Inhibits EMT and Liver Fibrosis via POSTN to Suppress Metastasis in Hepatocellular Carcinoma

Background

The asymptomatic onset, frequent recurrence, and poor prognosis of hepatocellular carcinoma (HCC) prompted us to identify new therapeutic targets or predictive markers of HCC diagnosis or prognosis.

Methods

In this study, bioinformatics analysis was used to screen for target miRNAs from the open-access TCGA database. Transwell assays, Western blotting, and qRT-PCR analyses were used to detect cellular functions and gene expression in HCC cells and samples. A nude mouse tumorigenesis model was established to facilitate the observation of HCC progression. Other assays included luciferase reporter assays, IHC, and survival analysis.

Results

We found that the identified miR-876 from TCGA was expressed at low levels in HCC cell lines and that low miR-876 expression was corrected with liver cirrhosis, tumor thrombus, and TNM stage. Further research revealed that miR-876 regulated cell invasion, EMT, and collagen expression by targeting POSTN expression. miR-876 and POSTN were inversely correlated in HCC samples and associated with EMT status and liver fibrosis in clinical HCC tissues. miR-876 inhibited the liver cancer progression in in vivo animal assays. Finally, both miR-876 and POSTN were risk factors for HCC survival, and HCC patients with combined low miR-876 and high POSTN expression had worse prognosis.

Conclusions

miR-876 inhibited HCC EMT and fibrosis by targeting POSTN, thus affecting HCC progression and prognosis. miR-876 and POSTN may be useful therapeutic targets or prognostic markers of HCC.

A Complex and Evolutive Character: Two Face Aspects of ECM in Tumor Progression

Tumor microenvironment, including extracellular matrix (ECM) and stromal cells, is a key player during tumor development, from initiation, growth and progression to metastasis. During all of these steps, remodeling of matrix components occurs, changing its biochemical and physical properties. The global and basic cancer ECM model is that tumors are surrounded by activated stromal cells, that remodel physiological ECM to evolve into a stiffer and more crosslinked ECM than in normal conditions, thereby increasing invasive capacities of cancer cells. In this review, we show that this too simple model does not consider the complexity, specificity and heterogeneity of each organ and tumor. First, we describe the general ECM in context of cancer. Then, we go through five invasive and most frequent cancers from different origins (breast, liver, pancreas, colon, and skin), and show that each cancer has its own specific matrix, with different stromal cells, ECM components, biochemical properties and activated signaling pathways. Furthermore, in these five cancers, we describe the dual role of tumor ECM: as a protective barrier against tumor cell proliferation and invasion, and as a major player in tumor progression. Indeed, crosstalk between tumor and stromal cells induce changes in matrix organization by remodeling ECM through invadosome formation in order to degrade it, promoting tumor progression and cell invasion. To sum up, in this review, we highlight the specificities of matrix composition in five cancers and the necessity not to consider the ECM as one general and simple entity, but one complex, dynamic and specific entity for each cancer type and subtype.

High-matrix-stiffness induces promotion of hepatocellular carcinoma proliferation and suppression of apoptosis via miR-3682-3p-PHLDA1-FAS pathway

Hepatocellular carcinoma (HCC) with malignant behaviors related to death causes distant metastasis and is the fourth primary cancer in the whole world, which has taken millions lives in Asian countries such as China. The novel miR-3682-3p involving high-expression-related poor prognosis in HCC tissues and cell lines indicate oncogenesis functions in vitro and in vivo. According to TCGA database, our group find several none-coding RNAs showing abnormal expression including miR-3682-3p, thus we originally confirmed the inhibition of proliferation and acceleration of apoptosis are enhanced in miR-3682-3p knock-down cell lines. Then, in nude mice transplantation assays, we found the suppressor behaviors, smaller nodules and lower speed of tumor expansion in model of injection of cell cultured and transfected shRNA-miR-3682-3p. A combination of databases (Starbase, Targetscan and MiRgator) illustrates miR-3682-3p targets PHLDA1, which shows negative correlation demonstrated by dual-luciferase reporter system. To make functional verification of PHLDA1, we upregulate the gene and rescue tests are established to confirm that miR-3682-3p suppresses PHLDA1 to promotion of cell growth. Rescue experiments finish making confirmation of relation of miR-3682-3p and PHLDA1 subsequently. Cirrhotic tissues illustrate strong correlation to higher miR-3682-3p and clinical features make the hint that high-extracellular-matrix-stiffness environment promotes such miRNA. Functional tests on different stiffness provide the proof of underlying mechanism. In conclusion, the overexpression of miR-3682-3p mediates PHLDA1 inhibition could impede apoptosis and elevate proliferation of HCC through high-extracellular-matrix-stiffness environment potentially.

Plasma Extracellular Vesicle-Derived TIMP-1 mRNA as a Prognostic Biomarker in Clear Cell Renal Cell Carcinoma: A Pilot Study

The tumor microenvironment has gained a lot of attention from the scientific community since it has a proven impact in the development of tumor progression and metastasis. Extracellular vesicles (EVs) are now considered one of the key players of tumor microenvironment modulation. Clear cell renal cell carcinoma (ccRCC) is the most lethal urological neoplasia and presents a high metastatic potential, which reinforces the need for the development of more effective predictive biomarkers. Our goal was to evaluate the applicability of EV-derived matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) as prognostic biomarkers for ccRCC. To do so, we studied the plasma EV content of 32 patients with localized ccRCC and 29 patients with metastatic ccRCC. We observed that patients with localized disease and tumors larger than 7 cm presented higher levels of plasma EV-derived TIMP-1 mRNA when compared with patients presenting smaller tumors (p = 0.020). Moreover, patients with metastatic disease presented higher levels of EV-derived TIMP-1 mRNA when compared with patients with localized disease (p = 0.002) and when we stratified those patients in high and low levels of TIMP-1 EV-derived mRNA, the ones presenting higher levels had a lower overall survival (p = 0.030). EV-derived TIMP-1 mRNA may be a good prognostic biomarker candidate for ccRCC.

HAND2-AS1 Inhibits Gastric Adenocarcinoma Cells Proliferation and Aerobic Glycolysis via miRNAs Sponge

Objective

To study the effect of lncRNA HAND2-AS1 on gastric adenocarcinoma (GA) cell property and explore its specific mechanism.

Methods

Data on stomach adenocarcinoma (STAD) were analyzed to screen differentially expressed lncRNA HAND2-AS1. RNA22-HAS database and dual luciferase reporter assay were applied to confirm the target relationship between HAND2-AS1/HIF3A and miR-184. The HAND2-AS1 and miR-184 expressions in tissue or cells were determined by qRT-PCR and Western blot. Besides, after GA cells (AGS) cultured in normoxic and hypoxic condition, phosphoenolpyruvate (PEP) and lactic acid were quantified by Phosphoenolpyruvate Fluorometric Assay Kit and Lactic Acid Detection kit, respectively. Additionally, colony formation assay, transwell invasion and migration assays were used to evaluate the abilities of cell invasion, migration, and proliferation in distinct conditions.

Results

The HAND2-AS1 and HIF3A expressions were down-regulated and miR-184 expression was up-regulated in GA tissues and cells. Dual luciferase reporter assay confirmed HAND2-AS1 and HIF3A were targeted by miR-184. AGS cell proliferation abilities were restrained by HAND2-AS1 and HIF3A overexpression and enhanced by miR-184, as well as migration and invasion abilities. In addition, HAND2-AS1 rescued enhanced AGS cell proliferation, cell migration, cell invasion abilities and glycolytic process caused by hypoxia via miR-184/HIF3A.

Conclusion

LncRNA HAND2-AS1 could inhibit GA cell proliferation, migration and invasion abilities and glycolytic process induced by hypoxia through miR-184/HIF3A signaling.

Crosstalk of MicroRNAs and Oxidative Stress in the Pathogenesis of Cancer

Oxidative stress refers to an imbalance between reactive oxygen species (ROS) generation and body's capability to detoxify the reactive mediators or to fix the relating damage. MicroRNAs are considered to be important mediators that play essential roles in the regulation of diverse aspects of carcinogenesis. Growing studies have demonstrated that the ROS can regulate microRNA biogenesis and expression mainly through modulating biogenesis course, transcription factors, and epigenetic changes. On the other hand, microRNAs may in turn modulate the redox signaling pathways, altering their integrity, stability, and functionality, thus contributing to the pathogenesis of multiple diseases. Both ROS and microRNAs have been identified to be important regulators and potential therapeutic targets in cancers. However, the information about the interplay between oxidative stress and microRNA regulation is still limited. The present review is aimed at summarizing the current understanding of molecular crosstalk between microRNAs and the generation of ROS in the pathogenesis of cancer.

Norepinephrine-CREB1-miR-373 axis promotes progression of colon cancer

The adrenergic system contributes to the stress‐induced onset and progression of cancer. Adrenergic fibers are the primary source of norepinephrine (NE). The underlying mechanisms involved in NE‐induced colon cancer remain to be understood. In this study, we describe the function and regulatory network of NE in the progression of colon cancer. We demonstrate that NE‐induced phosphorylation of cAMP response element‐binding protein 1 (CREB1) promotes proliferation, migration, and invasion of human colon cancer cells. The downstream effector of NE, CREB1, bound to the promoter of miR‐373 and transcriptionally activated its expression. miR‐373 expression was shown to be necessary for NE‐induced cell proliferation, invasion, and tumor growth. We confirmed that proliferation and invasion of colon cancer cells are regulated in vitro and in vivo by miR‐373 through targeting of the tumor suppressors TIMP2 and APC. Our data suggest that NE promotes colon cancer cell proliferation and metastasis by activating the CREB1–miR‐373 axis. The study of this novel signaling axis may provide mechanistic insights into the neural regulation of colon cancer and help in the design of future clinical studies on stress biology in colorectal cancer.

Microenvironment-induced TIMP2 loss by cancer-secreted exosomal miR-4443 promotes liver metastasis of breast cancer

We aimed to investigate the role of exosomal miR-4443 in metastasis of breast cancer (BCa). In vitro wound-healing assay and transwell invasion assay were used to investigate effect of miR-4443 on BCa cells. Animal experiments were performed to confirm its effects in vivo. miR-4443 promotes the metastasis of BCa cells through downregulating tissue inhibitors of metalloproteinase 2 (TIMP2) and upregulating matrix metalloproteinases (MMPs). Highly invasive BCa cells have a higher expression of miR-4443 in both cells and exosomes. The exosomes derived from highly invasive BCa cells mainly gather in the primary tumor and liver. In vivo, overexpression of miR-4443 in noninvasive BCa cells induces liver metastasis, accompanied with downregulated TIMP2, and upregulated MMP-2 in both the primary tumor and liver. When we armed MCF-10A exosomes with miR-4443 inhibitors to treat mice bearing high-miR-4443 tumors, exosomes accumulated in the primary tumor, and liver following the upregulation of TIMP2 and downregulation of MMP2, and the metastasis was inhibited. Highly invasive BCa cells destroy natural barriers against metastasis by delivering exosomal miR-4443 to stromal cells of the primary tumor and impairing TIMP2, consequently activating MMP; circulating exosomal miR-4443 might promote BCa cells lodging in future metastatic sites through the similar mechanisms.