KDM1A inhibition is effective in reducing stemness and treating triple negative breast cancer

KDM1A/LSD1 inhibition enhances chemotherapy response in ovarian cancer

Ovarian cancer (OCa) is the deadliest of all gynecological cancers. The standard treatment for OCa is platinum-based chemotherapy, such as carboplatin or cisplatin in combination with paclitaxel. Most patients are initially responsive to these treatments; however, nearly 90% will develop recurrence and inevitably succumb to chemotherapy-resistant disease. Recent studies have revealed that the epigenetic modifier lysine-specific histone demethylase 1A (KDM1A/LSD1) is highly overexpressed in OCa. However, the role of KDM1A in chemoresistance and whether its inhibition enhances chemotherapy response in OCa remains uncertain. Analysis of TCGA datasets revealed that KDM1A expression is high in patients who poorly respond to chemotherapy. Western blot analysis show that treatment with chemotherapy drugs cisplatin, carboplatin, and paclitaxel increased KDM1A expression in OCa cells. KDM1A knockdown (KD) or treatment with KDM1A inhibitors NCD38 and SP2509 sensitized established and patient-derived OCa cells to chemotherapy drugs in reducing cell viability and clonogenic survival and inducing apoptosis. Moreover, knockdown of KDM1A sensitized carboplatin-resistant A2780-CP70 cells to carboplatin treatment and paclitaxel-resistant SKOV3-TR cells to paclitaxel. RNA-seq analysis revealed that a combination of KDM1A-KD and cisplatin treatment resulted in the downregulation of genes related to epithelial-mesenchymal transition (EMT). Interestingly, cisplatin treatment increased a subset of NF-κB pathway genes, and KDM1A-KD or KDM1A inhibition reversed this effect. Importantly, KDM1A-KD, in combination with cisplatin, significantly reduced tumor growth compared to a single treatment in an orthotopic intrabursal OCa xenograft model. Collectively, these findings suggest that combination of KDM1A inhibitors with chemotherapy could be a promising therapeutic approach for the treatment of OCa.

The emerging roles of histone demethylases in cancers

Modulation of histone methylation status is regarded as an important mechanism of epigenetic regulation and has substantial clinical potential for the therapy of diseases, including cancer and other disorders. The present study aimed to provide a comprehensive introduction to the enzymology of histone demethylases, as well as their cancerous roles, molecular mechanisms, therapeutic possibilities, and challenges for targeting them, in order to advance drug design for clinical therapy and highlight new insight into the mechanisms of these enzymes in cancer. A series of clinical trials have been performed to explore potential roles of histone demethylases in several cancer types. Numerous targeted inhibitors associated with immunotherapy, chemotherapy, radiotherapy, and targeted therapy have been used to exert anticancer functions. Future studies should evaluate the dynamic transformation of histone demethylases leading to carcinogenesis and explore individual therapy.

Therapeutic vulnerabilities in triple negative breast cancer: Stem-like traits explored within molecular classification

Triple Negative Breast Cancer (TNBC) is the most aggressive type of breast cancer (BC). Despite advances in the clinical management of TNBC, recurrence-related mortality remains a challenge. The stem-like phenotype of TNBC plays a significant role in the persistence of minimal disease residue after therapy. Individuals exhibiting stem-like characteristics are particularly prone to inducing malignant relapse accompanied by strong resistance. Therefore, stem-like traits have been broadly proposed as therapeutic vulnerabilities to treat TNBC and reduce recurrence. However, heterogeneity within TNBC often generally restricts the stability of the therapeutic efficacy. To understand the heterogeneity and manage TNBC more precisely, multiple TNBC subtyping categories have been reported, providing the basis for profile-according therapeutic regimens. To provide more insight into targeting stem-like traits to ablate TNBC and reduce recurrence in the context of heterogeneity, this paper reviewed the molecular subtyping of TNBC, identified the consensus subtypes with distinct stem-like phenotypes, characterized the stemness hierarchy of TNBC, outlined the biological models for stem-like TNBC subtypes, summarized the therapeutic vulnerabilities in stem-like traits of the subtypes, and proposed potential therapeutic regimens targeting stem-like characteristics to improve TNBC prognosis.

Tanshinone IIA destabilizes SLC7A11 by regulating PIAS4-mediated SUMOylation of SLC7A11 through KDM1A, and promotes ferroptosis in breast cancer

INTRODUCTION

Breast cancer (BC) is the most common malignancy in women with unfavorite prognosis.

OBJECTIVES

Tanshinone IIA (Tan IIA) inhibits BC progression, however, the underlying mechanism remains largely undefined.

METHODS

The cytotoxicity of Tan IIA was assessed by CCK-8 and LDH assays. Ferroptosis was monitored by the level of MDA, Fe2+, lipid ROS and GSH. IHC and western blot were employed to detect the localization and expression of SLC7A11, PIAS4, KDM1A and other key molecules. The SUMOylation of SLC7A11 was detected by Ni-beads pull-down assay and co-IP. Luciferase and ChIP assays were employed to detect the direct association between KDM1A and PIAS4 promoter. The proliferative and metastatic properties of BC cells were assessed by colony formation, CCK-8 and Transwell assays, respectively. The in vitro findings were verified in xenograft and lung metastasis models.

RESULTS

Tan IIA promoted ferroptosis by suppressing SLC7A11 in BC cells. Silencing of PIAS4 or KDM1A inhibited cell growth and metastasis in BC. Mechanistically, PIAS4 facilitated the SUMOylation of SLC7A11 via direct binding to SLC7A11, and KDM1A acted as a transcriptional activator of PIAS4. Functional studies further revealed that Tan IIA decreased KDM1A expression, thus suppressing PIAS4 expression transcriptionally. The inhibition of PIAS4-dependent SUMOylation of SLC7A11 further induced ferroptosis, thereby inhibiting proliferation and metastasis in BC.

CONCLUSION

Tan IIA promoted ferroptosis and inhibited tumor growth and metastasis via suppressing KDM1A/PIAS4/SLC7A11 axis.

The Killer's Web: Interconnection between Inflammation, Epigenetics and Nutrition in Cancer

Inflammation is a key contributor to both the initiation and progression of tumors, and it can be triggered by genetic instability within tumors, as well as by lifestyle and dietary factors. The inflammatory response plays a critical role in the genetic and epigenetic reprogramming of tumor cells, as well as in the cells that comprise the tumor microenvironment. Cells in the microenvironment acquire a phenotype that promotes immune evasion, progression, and metastasis. We will review the mechanisms and pathways involved in the interaction between tumors, inflammation, and nutrition, the limitations of current therapies, and discuss potential future therapeutic approaches.

Pharmacological inhibition of KDM1A/LSD1 enhances estrogen receptor beta-mediated tumor suppression in ovarian cancer

Ovarian cancer (OCa) is the most lethal gynecologic cancer. Emerging data indicates that estrogen receptor beta (ERβ) functions as a tumor suppressor in OCa. Lysine-specific histone demethylase 1A (KDM1A) is an epigenetic modifier that acts as a coregulator for steroid hormone receptors. However, it remain unknown if KDM1A interacts with ERβ and regulates its expression/functions in OCa. Analysis of TCGA data sets indicated KDM1A and ERβ expression showed an inverse relationship in OCa. Knockout (KO), knockdown (KD), or inhibition of KDM1A increased ERβ isoform 1 expression in established and patient-derived OCa cells. Further, KDM1A interacts with and functions as a corepressor of ERβ, and its inhibition enhances ERβ target gene expression via alterations of histone methylation marks at their promoters. Importantly, KDM1A-KO or -KD enhanced the efficacy of ERβ agonist LY500307, and the combination of KDM1A inhibitor (KDM1Ai) NCD38 with ERβ agonist synergistically reduced the cell viability, colony formation, and invasion of OCa cells. RNA-seq and DIA mass spectrometry analyses showed that KDM1A-KO resulted in enhanced ERβ signaling and that genes altered by KDM1A-KO and ERβ agonist were related to apoptosis, cell cycle, and EMT. Moreover, combination treatment significantly reduced the tumor growth in OCa orthotopic, syngeneic, and patient-derived xenograft models and proliferation in patient-derived explant models. Our results demonstrate that KDM1A regulates ERβ expression/functions, and its inhibition improves ERβ mediated tumor suppression. Overall, our findings suggest that KDM1Ai and ERβ agonist combination therapy is a promising strategy for OCa.

Lysine-specific histone demethylase 1A (KDM1A/LSD1) inhibition attenuates DNA double-strand break repair and augments the efficacy of temozolomide in glioblastoma

BACKGROUND

Efficient DNA repair in response to standard chemo and radiation therapies often contributes to glioblastoma (GBM) therapy resistance. Understanding the mechanisms of therapy resistance and identifying the drugs that enhance the therapeutic efficacy of standard therapies may extend the survival of GBM patients. In this study, we investigated the role of KDM1A/LSD1 in DNA double-strand break (DSB) repair and a combination of KDM1A inhibitor and temozolomide (TMZ) in vitro and in vivo using patient-derived glioma stem cells (GSCs).

METHODS

Brain bioavailability of the KDM1A inhibitor (NCD38) was established using LS-MS/MS. The effect of a combination of KDM1A knockdown or inhibition with TMZ was studied using cell viability and self-renewal assays. Mechanistic studies were conducted using CUT&Tag-seq, RNA-seq, RT-qPCR, western blot, homologous recombination (HR) and non-homologous end joining (NHEJ) reporter, immunofluorescence, and comet assays. Orthotopic murine models were used to study efficacy in vivo.

RESULTS

TCGA analysis showed KDM1A is highly expressed in TMZ-treated GBM patients. Knockdown or knockout or inhibition of KDM1A enhanced TMZ efficacy in reducing the viability and self-renewal of GSCs. Pharmacokinetic studies established that NCD38 readily crosses the blood-brain barrier. CUT&Tag-seq studies showed that KDM1A is enriched at the promoters of DNA repair genes and RNA-seq studies confirmed that KDM1A inhibition reduced their expression. Knockdown or inhibition of KDM1A attenuated HR and NHEJ-mediated DNA repair capacity and enhanced TMZ-mediated DNA damage. A combination of KDM1A knockdown or inhibition and TMZ treatment significantly enhanced the survival of tumor-bearing mice.

CONCLUSIONS

Our results provide evidence that KDM1A inhibition sensitizes GBM to TMZ via attenuation of DNA DSB repair pathways.

Zinc finger and SCAN domain-containing protein 18 is a potential DNA methylation-modified tumor suppressor and biomarker in breast cancer

Introduction

Zinc finger and SCAN domain-containing protein 18 (ZSCAN18) has been investigated as a putative biomarker of multiple human cancers. However, the expression profile, epigenetic modification, prognostic value, transcription regulation, and molecular mechanism of ZSCAN18 in breast cancer (BC) remain unknown.

Methods

In the study, we present an integrated analysis of ZSCAN18 in BC based on public omics datasets with the use of multiple bioinformatics tools. Genes potentially regulated through restoration of ZSCAN18 expression in MDA-MB-231 cells were investigated to identify pathways associated with BC.

Results

We observed that ZSCAN18 was downregulated in BC and mRNA expression was significantly correlated with clinicopathological parameters. Low expression of ZSCAN18 was found in the HER2-positive and TNBC subtypes. High expression of ZSCAN18 was associated with good prognosis. As compared to normal tissues, the extent of ZSCAN18 DNA methylation was greater with fewer genetic alterations in BC tissues. ZSCAN18 was identified as a transcription factor that might be involved in intracellular molecular and metabolic processes. Low ZSCAN18 expression was associated with the cell cycle and glycolysis signaling pathway. Overexpression of ZSCAN18 inhibited mRNA expression of genes associated with the Wnt/β-catenin and glycolysis signaling pathways, including CTNNB1, BCL9, TSC1, and PFKP. ZSCAN18 expression was negatively correlated with infiltrating B cells and dendritic cells (DCs), as determined by the TIMER web server and reference to the TISIDB. ZSCAN18 DNA methylation was positively correlated with activated B cells, activated CD8+ and CD4+ T cells, macrophages, neutrophils, and activated DCs. Moreover, five ZSCAN18-related hub genes (KDM6B, KAT6A, KMT2D, KDM1A, and HSPBP1) were identified. ZSCAN18, ZNF396, and PGBD1 were identified as components of a physical complex.

Conclusion

ZSCAN18 is a potential tumor suppressor in BC, as expression is modified by DNA methylation and associated with patient survival. In addition, ZSCAN18 plays important roles in transcription regulation, the glycolysis signaling pathway, and the tumor immune microenvironment.

KDM1A drives hepatoblastoma progression by activating the Wnt/β-catenin pathway through inhibition of DKK3 transcription

This study is to explore the mechanism of KDM1A-regulated hepatoblastoma (HB) development. Cancerous and paracancer tissues of 30 HB patients were collected for detection of KDM1A and DKK3 expression. HuH-6 and HepG2 cells were subjected to assays of cellular activities after treatment with sh-KDM1A, sh-DKK3, and/or XAV-939 (an inhibitor of the Wnt/β-catenin pathway). Chromatin immunoprecipitation was used to determine the interaction of KDM1A with DKK3. Nude mice were injected with HuH-6 cells in which KDM1A was knocked down. KDM1A was highly expressed and DKK3 was lowly expressed in HB patients. Knockdown of KDM1A reduced the proliferative and invasive capabilities of HepG2 and HuH-6 cells and accelerated the cell apoptosis; these influences were nullified by knockdown of DKK3. KDM1A inhibited DKK3 transcription by reducing H3 methylation. XAV-939 treatment inhibited the development of HepG2 and HuH-6 cells in which KDM1A and DKK3 were both knocked down. Knockdown of KDM1A reduced the tumor mass, inactivated the Wnt/β-catenin signaling, and increased the expression of DKK3 in nude mice. KDM1A stimulates HB development by activating the Wnt/β-catenin pathway through inhibition of DKK3 transcription.

microRNA-17 is a tumor suppressor in oral squamous cell carcinoma and is repressed by LSD1

OBJECTIVE

The effects of epigenetic modifiers have been uncovered on cellular reprogramming and, specifically, on sustaining characteristics of cancer stem cells. We here aim to investigate whether lysine-specific demethylase 1 (LSD1) affects the development of oral squamous cell carcinoma (OSCC) by sustaining the cancer stem cells from OSCC (OSCSCs).

METHODS

RT-qPCR detection was firstly conducted to screen out research gene by determining differential expression of histone demethylases and methylases in identified OSCSCs. Then, microarray analysis was carried out in cells with poor expression of LSD1.

RESULTS

OSCSCs expressed high levels of LSD1, and LSD1 inhibition reduced cell viability, migration, invasion, and sphere formation of OSCSCs. Later mechanistic studies suggested that LSD1 inhibited microRNA (miR)-17 expression through histone demethylation. miR-17 bound to KPNA2, and LSD1 downstream genes were mainly enriched in the PI3K/AKT pathway. Importantly, miR-17 inhibitor reversed the inhibitory effect of si-LSD1 on cell activity, while si-KPNA2 abolished the promotive effect of miR-17 inhibitor on cell activity both in vitro and in vivo.

CONCLUSION

Overall, LSD1 functions as a cancer stem cell supporter in OSCC by catalyzing demethylation of miR-17 and activating the downstream KPNA2/PI3K/AKT pathway, which contributes to understanding of the mechanisms associated with epigenetic regulation in OSCC.

LSD1 inhibitors for cancer treatment: Focus on multi-target agents and compounds in clinical trials

Histone lysine-specific demethylase 1 (LSD1/KDM1A) was first identified in 2004 as an epigenetic enzyme able to demethylate specific lysine residues of histone H3, namely H3K4me1/2 and H3K9me1/2, using FAD as the cofactor. It is ubiquitously overexpressed in many types of cancers (breast, gastric, prostate, hepatocellular, and esophageal cancer, acute myeloid leukemia, and others) leading to block of differentiation and increase of proliferation, migration and invasiveness at cellular level. LSD1 inhibitors can be grouped in covalent and non-covalent agents. Each group includes some hybrid compounds, able to inhibit LSD1 in addition to other target(s) at the same time (dual or multitargeting compounds). To date, 9 LSD1 inhibitors have entered clinical trials, for hematological and/or solid cancers. Seven of them (tranylcypromine, iadademstat (ORY-1001), bomedemstat (IMG-7289), GSK-2879552, INCB059872, JBI-802, and Phenelzine) covalently bind the FAD cofactor, and two are non-covalent LSD1 inhibitors [pulrodemstat (CC-90011) and seclidemstat (SP-2577)]. Another TCP-based LSD1/MAO-B dual inhibitor, vafidemstat (ORY-2001), is in clinical trial for Alzheimer's diseases and personality disorders. The present review summarizes the structure and functions of LSD1, its pathological implications in cancer and non-cancer diseases, and the identification of LSD1 covalent and non-covalent inhibitors with different chemical scaffolds, including those involved in clinical trials, highlighting their potential as potent and selective anticancer agents.

YTH Domain Family 2 (YTHDF2) Regulates Cell Growth and Cycle by Facilitating KDM1A mRNA Stability

Breast cancer is the leading cause of cancer death in women. More than one million women worldwide are diagnosed with breast cancer each year, and the incidence rates are increasing. The physiological functions of N6-methyladenosine methylation in cancer have been appreciated in recent years. Herein, four data sets (GSE70947, GSE45827, GSE42586, and The Cancer Genome Atlas Breast Cancer) were analyzed to confirm the differentially expressed N6-methyladenosine genes. YTHDF2 was found to be highly expressed in breast cancer tissues and cells. In vitro, YTHDF2 affects cell proliferation, the cell cycle, and invasive ability. Tumorigenesis in xenograft nude mice confirmed that YTHDF2 interference reduced the tumor formation ability of cancer cells. Pearson correlation analysis demonstrated a positive correlation between YTHDF2 and KDM1A. An online tool (SRAMP) predicted that there are eight methylation sites in the KDM1A mRNA sequence. The expression of KDM1A was dramatically increased in breast cancer tissues and cells. Down-regulation of YTHDF2 reduced KDM1A expression and the methylation level of KDM1A mRNA. YTHDF2 interference promoted the degradation of KDM1A mRNA, which suggested an interaction between YTHDF2 and KDM1A. KDM1A interference altered cell proliferation, cell cycle, and invasive ability, whereas YTHDF2 overexpression rescued KDM1A interference-induced cell phenotypic changes. In conclusion, YTHDF2 promotes breast cancer cell growth and cell cycle progression by facilitating KDM1A mRNA stability. This study provides new therapeutic targets for breast cancer treatment in the future.

A state-of-the-art review on LSD1 and its inhibitors in breast cancer: Molecular mechanisms and therapeutic significance

Breast cancer (BC) is a kind of malignant cancer in women, and it has become the most diagnosed cancer worldwide since 2020. Histone methylation is a common biological epigenetic modification mediating varieties of physiological and pathological processes. Lysine-specific demethylase 1 (LSD1), a first identified histone demethylase, mediates the removal of methyl groups from histones H3K4me1/2 and H3K9me1/2 and plays a crucial role in varieties of cancer progression. It is also specifically amplified in breast cancer and contributes to BC tumorigenesis and drug resistance via both demethylase and non-demethylase manners. This review will provide insight into the overview structure of LSD1, summarize its action mechanisms in BC, describe the therapeutic potential of LSD1 inhibitors in BC, and prospect the current opportunities and challenges of targeting LSD1 for BC therapy.

Therapeutic opportunities to modulate immune tolerance through the metabolism-chromatin axis

The ability of the immune system to discriminate external stimuli from self-components - namely immune tolerance - occurs through a coordinated cascade of events involving a dense network of immune cells. Among them, CD4⁺CD25⁺ T regulatory cells are crucial to balance immune homeostasis and function. Growing evidence supports the notion that energy metabolites can dictate T cell fate and function via epigenetic modifications, which affect gene expression without altering the DNA sequence. Moreover, changes in cellular metabolism couple with activation of immune pathways and epigenetic remodeling to finely tune the balance between T cell activation and tolerance. This Review summarizes these aspects and critically evaluates novel possibilities for developing therapeutic strategies to modulate immune tolerance through metabolism via epigenetic drugs.

Targeting Cancer Stem Cells through Epigenetic Modulation of Interferon Response

Cancer stem cells (CSCs) are a small subset of cancer cells and are thought to play a critical role in the initiation and maintenance of tumor mass. CSCs exhibit similar hallmarks to normal stem cells, such as self-renewal, differentiation, and homeostasis. In addition, CSCs are equipped with several features so as to evade anticancer mechanisms. Therefore, it is hard to eliminate CSCs by conventional anticancer therapeutics that are effective at clearing bulk cancer cells. Interferons are innate cytokines and are the key players in immune surveillance to respond to invaded pathogens. Interferons are also crucial for adaptive immunity for the killing of specific aliens including cancer cells. However, CSCs usually evolve to escape from interferon-mediated immune surveillance and to shape the niche as a “cold” tumor microenvironment (TME). These CSC characteristics are related to their unique epigenetic regulations that are different from those of normal and bulk cancer cells. In this review, we introduce the roles of epigenetic modifiers, focusing on LSD1, BMI1, G9a, and SETDB1, in contributing to CSC characteristics and discussing the interplay between CSCs and interferon response. We also discuss the emerging strategy for eradicating CSCs by targeting these epigenetic modifiers, which can elevate cytosolic nuclei acids, trigger interferon response, and reshape a “hot” TME for improving cancer immunotherapy. The key epigenetic and immune genes involved in this crosstalk can be used as biomarkers for precision oncology.

Role of histone demethylases and histone methyltransferases in triple-negative breast cancer: Epigenetic mnemonics

Triple-negative breast cancer (TNBC) is a particularly lethal subtype of breast cancer owing to its heterogeneity, high drug resistance, poor prognosis and lack of therapeutic targets. Recent insights into the complexity of TNBC have been explained by epigenetic regulation and its ability to modulate certain oncogenes and tumour suppressor genes. This has opened an emerging area in anti-cancer therapy using epigenetic modulating drugs, highlighting the epigenetic reprogramming during tumorigenesis and tumour development. Histone methylation and demethylation are such dynamic epigenetic mechanisms mediated by histone methyltransferases (HMTs) and histone demethylases (HDMs), respectively. The interplay between HMTs and HDMs in histone methylation extrapolates their viability as druggable epigenetic targets in TNBC. In this review, we aim to summarize recent progress in the field of epigenetics focusing on HMTs and HDMs in TNBC development and their potential use in targeted therapy for TNBC management.

Prognostic Value of mRNAsi/Corrected mRNAsi Calculated by the One-Class Logistic Regression Machine-Learning Algorithm in Glioblastoma Within Multiple Datasets

Glioblastoma (GBM) is the most common glial tumour and has extremely poor prognosis. GBM stem-like cells drive tumorigenesis and progression. However, a systematic assessment of stemness indices and their association with immunological properties in GBM is lacking. We collected 874 GBM samples from four GBM cohorts (TCGA, CGGA, GSE4412, and GSE13041) and calculated the mRNA expression-based stemness indices (mRNAsi) and corrected mRNAsi (c_mRNAsi, mRNAsi/tumour purity) with OCLR algorithm. Then, mRNAsi/c_mRNAsi were used to quantify the stemness traits that correlated significantly with prognosis. Additionally, confounding variables were identified. We used discrimination, calibration, and model improvement capability to evaluate the established models. Finally, the CIBERSORTx algorithm and ssGSEA were implemented for functional analysis. Patients with high mRNAsi/c_mRNAsi GBM showed better prognosis among the four GBM cohorts. After identifying the confounding variables, c_mRNAsi still maintained its prognostic value. Model evaluation showed that the c_mRNAsi-based model performed well. Patients with high c_mRNAsi exhibited significant immune suppression. Moreover, c_mRNAsi correlated negatively with infiltrating levels of immune-related cells. In addition, ssGSEA revealed that immune-related pathways were generally activated in patients with high c_mRNAsi. We comprehensively evaluated GBM stemness indices based on large cohorts and established a c_mRNAsi-based classifier for prognosis prediction.

Long non-coding RNA NORAD induces phenotypic regulation of vascular smooth muscle cells through regulating microRNA-136-5p-targeted KDM1A

OBJECTIVE

Effect of long non-coding RNAs (lncRNAs) on intracranial aneurysm (IA) development has been identified, while the role of noncoding RNA activated by DNA damage (NORAD) in IA remains unexplored. We aimed to verify the impact of NORAD on IA through sponging microRNA-136-5p (miR-136-5p).

METHODS

Ruptured and unruptured IAs were harvested from IA patients, and expression of NORAD, miR-136-5p, and KDM1A was determined. The vascular smooth muscle cells (VSMCs) were cultured and, respectively, transfected with altered NORAD, miR-136-5p, or lysine-specific demethylase 1 (KDM1A) to observe their effect on biological functions, as well as on contraction and synthesis-specific indices of VSMCs. Interactions between NORAD and miR-136-5p, and between miR-136-5p and KDM1A were confirmed.

RESULTS

NORAD and KDM1A were upregulated while miR-136-5p was downregulated in IA, especially in ruptured IA. NORAD overexpression or miR-136-5p inhibition accelerated proliferation and migration, and decelerated phenotypic switching and apoptosis of VSMCs. The effects of overexpressed NORAD on VSMCs were reserved by miR-136-5p upregulation or KDM1A knockdown. NORAD functioned as a competing endogenous RNA of miR-136-5p and miR-136-5p targeted KDM1A.

CONCLUSION

NORAD suppressed miR-136-5p, thus upregulating KDM1A to participate in IA formation and rupture by inducing phenotypic regulation of VSMCs.

Modulating cell differentiation in cancer models

Cancer has been traditionally viewed as a disease characterised by excessive and uncontrolled proliferation, leading to the development of cytotoxic therapies against highly proliferating malignant cells. However, tumours frequently relapse due to the presence of slow-cycling cancer stem cells eluding chemo and radiotherapy. Since these malignant stem cells are largely undifferentiated, inducing their lineage commitment has been proposed as a potential intervention strategy to deplete tumours from their most resistant components. Pro-differentiation approaches have thus far yielded clinical success in the reversion of acute promyelocytic leukaemia (APL), and new developments are fast widening their therapeutic applicability to solid carcinomas. Recent advances in cancer differentiation discussed here highlight the potential and outstanding challenges of differentiation-based approaches.

Prognostic Value of miR-137 in Children with Medulloblastoma and its Regulatory Effect on Tumor Progression

Medulloblastoma is a malignant tumor with high incidence and poor prognosis in adolescents and children. MicroRNA-137 (miR-137) has been found to be abnormally expressed in cancers such as pancreatic cancer. The purpose of this study is to explore the expression of miR-137 in MB and its role in cell physiological activities to determine the significance of miR-137 in the prognosis of MB. First, the expression of miR-137 in MB tissues and cell lines was analyzed by qRT-PCR. Then the Kaplan-Meier survival curve was used to analyze the significance of miR-137 expression in the prognosis, and the Cox regression model was used to explore the correlation between miR-137 expression and clinical characteristics. The effects of miR-137 on MB cell activities were analyzed by MTT assay, Transwell assays, and flow cytometry. It can be concluded from the results that the expression of miR-137 is down-regulated in MB tissues and cells. The down-regulation of miR-137 was significantly related to the poor prognosis of MB, and significantly related to clinical indicators. Up-regulated miR-137 inhibited cell proliferation, migration, invasion, and cell cycle progression, as well as induced cell apoptosis by targeting KDM1A. This study can conclude that miR-137 may be used as a prognostic biomarker of MB.

Epigenetic Regulation of Breast Cancer Stem Cells Contributing to Carcinogenesis and Therapeutic Implications

Globally, breast cancer has remained the most commonly diagnosed cancer and the leading cause of cancer death among women. Breast cancer is a highly heterogeneous and phenotypically diverse group of diseases, which require different selection of treatments. Breast cancer stem cells (BCSCs), a small subset of cancer cells with stem cell-like properties, play essential roles in breast cancer progression, recurrence, metastasis, chemoresistance and treatments. Epigenetics is defined as inheritable changes in gene expression without alteration in DNA sequence. Epigenetic regulation includes DNA methylation and demethylation, as well as histone modifications. Aberrant epigenetic regulation results in carcinogenesis. In this review, the mechanism of epigenetic regulation involved in carcinogenesis, therapeutic resistance and metastasis of BCSCs will be discussed, and finally, the therapies targeting these biomarkers will be presented.

The epigenetics of breast cancer - Opportunities for diagnostics, risk stratification and therapy

The stage and molecular pathology-dependent prognosis of breast cancer, the limited treatment options for triple-negative carcinomas, as well as the development of resistance to therapies illustrate the need for improved early diagnosis and the development of new therapeutic approaches. Increasing data suggests that some answers to these challenges could be found in the area of epigenetics. In this study, we focus on the current research of the epigenetics of breast cancer, especially on the potential of epigenetics for clinical application in diagnostics, risk stratification and therapy. The differential DNA methylation status of specific gene regions has been used in the past to differentiate breast cancer cells from normal tissue. New technologies as detection of circulating nucleic acids including microRNAs to early detect breast cancer are emerging. Pattern of DNA methylation and expression of histone-modifying enzymes have been successfully used for risk stratification. However, all these epigenetic biomarkers should be validated in larger clinical studies. Recent preclinical and clinical studies show a therapeutic benefit of epigenetically active drugs for breast cancer entities that are still difficult to treat (triple negative, UICC stage IV). Remarkably, epigenetic therapies combined with chemotherapies or hormone-based therapies represent the most promising strategy. At the current stage, the integration of epigenetic substances into established breast cancer therapy protocols seems to hold the greatest potential for a clinical application of epigenetic research.