Downregulation of Long Noncoding RNA HOTAIR and EZH2 Induces Apoptosis and Inhibits Proliferation, Invasion, and Migration of Human Breast Cancer Cells

Combined inhibition of EZH2 and CD73 molecules by folic acid-conjugated SPION-TMC nanocarriers loaded with siRNA molecules prevents TNBC progression and restores anti-tumor responses

BACKGROUND

Abnormal function or overexpression of CD73 and EZH2 within the tumor microenvironment and tumor cells enhances tumor growth and progression, and in many cases, causes drug resistance. Hence, it seems that silencing the expression of CD73 and EZH2 molecules in breast cancer reduces cancer development and enhances anti-tumor immune responses.

METHODS

we used siRNA-loaded superparamagnetic iron oxide (SPIONs) nanoparticles (NPs) coated with trimethyl chitosan (TMC) and functionalized with folic acid for co-delivery of EZH2/CD73 siRNAs to 4 T1 murine cancer cells both in vitro and in vivo.

RESULTS

Combination therapy markedly inhibited cancer cells' proliferation, migration, and viability and induced apoptosis in vitro. Moreover, in vivo administration of this combination therapy promoted tumor regression and induced anti-tumor immune responses.

DISCUSSION

The findings indicated the CD73/EZH2 factors inhibition by SPION-TMC-FA NPs as a promising therapeutic strategy in breast cancer treatment.

What is beyond LncRNAs in breast cancer: A special focus on colon cancer-associated Transcript-1 (CCAT-1)

Long non-coding RNAs (LncRNAs) play a vital role in the process of malignant transformation. In breast cancer (BC), lncRNAs field is currently under intensive investigations. Yet, the role of lncRNAs as promising diagnostic and/or prognostic biomarkers and as therapeutic target/tool among BC patients still needs a special focus from the biomedical scientists. In BC, triple negative breast cancer patients (TNBC) are the unlucky group as they are always represented with the worst prognosis and the highest mortality rates. For that reason, a special focus on TNBC and associated lncRNAs was addressed in this review. Colon cancer-associated transcript 1 (CCAT-1) is a newly discovered oncogenic lncRNA that has been emerged as a vital biomarker for diagnosis, prognosis and therapeutic interventions in multiple malignancies and showed differential expression among TNBC patients. In this review, the authors shed the light onto the general role of lncRNAs in BC and the specific functional activities, molecular mechanisms, competing endogenous ncRNA role of CCAT-1 in TNBC.

LncRNA ANCR promotes glioma cells invasion, migration, proliferation and inhibits apoptosis via interacting with EZH2 and repressing PTEN expression

Recently, the role of long noncoding RNA (lncRNA) has been identified in human diseases, and we aim to explore the role of lncRNA antidifferentiation noncoding RNA (ANCR) in glioma. Expression of lncRNA ANCR, enhancer of zeste homolog 2 (EZH2), and phosphatase and tensin homolog (PTEN) in glioma tissues and cells was determined by RT-PCR or western blot assay. The correlation between expression of ANCR, EZH2, and PTEN in glioma tissues was analyzed using Pearson test. The apoptosis, transwell invasion, migration, colony formation, and proliferation assays were conducted to evaluate the influences of lncRNA ANCR depletion, EZH2 reduction, or PTEN elevation on the cell biology of glioma cells. The relationships between ANCR and EZH2, and between EZH2 and PTEN were confirmed through RIP, RNA pull-down, and chromatin immunoprecipitation assays. Our results indicated that ANCR and EZH2 were upregulated and PTEN was downregulated in glioma tissues and cell lines. ANCR expression was positively related to EZH2 expression, while PTEN expression was negatively related to ANCR/EZH2 expression. Inhibited ANCR, reduced EZH2, or elevated PTEN could reduce the ability of invasion, migration, and proliferation, and promote apoptosis of glioma cells. PTEN overexpression or EZH2 inhibition reversed the promotive role of ANCR upregulation in glioma cell growth and metastasis. Mechanistically, PTEN was upregulated in ANCR knockdown glioma cells. EZH2 interacted with ANCR in glioma cells. In conclusion, we have found that restrained ANCR could repress invasion, migration, and proliferation, as well as promote apoptosis of glioma cells through interacting with EZH2 and regulating the expression of PTEN, offering an effective therapeutic target for patients with glioma.

From Micro to Long: Non-Coding RNAs in Tamoxifen Resistance of Breast Cancer Cells

Breast cancer is the most commonly diagnosed cancer and the leading cause of cancer mortality among women. Two thirds of patients are classified as hormone receptor positive, based on expression of estrogen receptor alpha (ERα), the main driver of breast cancer cell proliferation, and/or progesterone receptor, which is regulated by ERα. Despite presenting the best prognosis, these tumors can recur when patients acquire resistance to treatment by aromatase inhibitors or antiestrogen such as tamoxifen (Tam). The mechanisms that are involved in Tam resistance are complex and involve multiple signaling pathways. Recently, roles for microRNAs and lncRNAs in controlling ER expression and/or tamoxifen action have been described, but the underlying mechanisms are still little explored. In this review, we will discuss the current state of knowledge on the roles of microRNAs and lncRNAs in the main mechanisms of tamoxifen resistance in hormone receptor positive breast cancer. In the future, this knowledge can be used to identify patients at a greater risk of relapse due to the expression patterns of ncRNAs that impact response to Tam, in order to guide their treatment more efficiently and possibly to design therapeutic strategies to bypass mechanisms of resistance.

RNA Interference and Nanotechnology: A Promising Alliance for Next Generation Cancer Therapeutics

Cancer is a significant health hazard of the 21st century, and GLOBOCAN predicts increasing cancer incidence in the coming decades. Though several conventional treatment modalities exist, most of them end up causing off-target and debilitating effects, and drug resistance acquisition. Advances in our understanding of tumor molecular biology offer alternative strategies for precise, robust, and potentially less toxic treatment paradigms for circumventing the disease at the cellular and molecular level. Several deregulated molecules associated with tumorigenesis have been developed as targets in RNA interference (RNAi) based cancer therapeutics. RNAi, a post-transcriptional gene regulation mechanism, has significantly gained attention because of its precise multi-targeted gene silencing. Although the RNAi approach is favorable, the direct administration of small oligonucleotides has not been fruitful because of their inherent lower half-lives and instability in the biological systems. Moreover, the lack of an appropriate delivery system to the primary site of the tumor that helps determine the potency of the drug and its reach, has limited the effective medical utilization of these bio-drugs. Nanotechnology, with its unique characteristics of enhanced permeation and better tumor-targeting efficiency, offers promising solutions owing to the various possibilities and amenability for modifications of the nanoparticles to augment cancer therapeutics. Nanoparticles could be made multimodal, by designing and synthesizing multiple desired functionalities, often resulting in unique and potentially applicable biological structures. A small number of Phase I clinical trials with systemically administered siRNA molecules conjugated with nanoparticles have been completed and the results are promising, indicating that, these new combinatorial therapies can successfully and safely be used to inhibit target genes in cancer patients to alleviate some of the disease burden. In this review, we highlight different types of nano-based delivery strategies for engineering Nano-RNAi-based bio drugs. Furthermore, we have highlighted the insights gained from current research that are entering the preclinical evaluation and information about initial clinical developments, shaping the future for next generation cancer therapeutics.

Methylation Landscape: Targeting Writer or Eraser to Discover Anti-Cancer Drug

Cancer is a major global health challenge for our health system, despite the important pharmacological and therapeutic discoveries we have seen since past 5 decades. The increasing prevalence and mortality of cancer may be closely related to smoking, exposure to environmental pollution, dietary and genetic factors. Despite significant promising discoveries and developments such as cell and biotechnological therapies a new breakthrough in the medical field is needed to develop specific and effective drugs for cancer treatment. On the development of cell therapies, anti-tumor vaccines, and new biotechnological drugs that have already shown promising effects in preclinical studies. With the continuous enrichment and development of chromatin immunoprecipitation sequencing (ChIP-seq) and its derivative technologies, epigenetic modification has gradually become a research hotspot. As key ingredients of epigenetic modification, Writers, Readers, Erasers have been gradually unveiled. Cancer has been associated with epigenetic modification especially methylation and therefore different epigenetic drugs have been developed and some of those are already undergoing clinical phase I or phase II trials, and it is believed that these drugs will certainly assist the treatment in the near future. With respect to this, an overview of anti-tumor drugs targeting modified enzymes and de-modified enzymes will be performed in order to contribute to future research.

Involvement of transcribed lncRNA uc.291 and SWI/SNF complex in cutaneous squamous cell carcinoma

While non-melanoma skin cancers (NMSCs) are the most common tumours in humans, only the sub-type cutaneous squamous cell carcinoma (cSCC), might become metastatic with high lethality. We have recently identified a regulatory pathway involving the lncRNA transcript uc.291 in controlling the expression of epidermal differentiation complex genes via the interaction with ACTL6A, a component of the chromatin remodelling complex SWI/SNF. Since transcribed ultra-conserved regions (T-UCRs) are expressed in normal tissues and are deregulated in tumorigenesis, here we hypothesize a potential role for dysregulation of this axis in cSCC, accounting for the de-differentiation process observed in aggressive poorly differentiated cutaneous carcinomas. We therefore analysed their expression patterns in human tumour biopsies at mRNA and protein levels. The results suggest that by altering chromatin accessibility of the epidermal differentiation complex genes, down-regulation of uc.291 and BRG1 expression contribute to the de-differentiation process seen in keratinocyte malignancy. This provides future direction for the identification of clinical biomarkers in cutaneous SCC. Analysis of publicly available data sets indicates that the above may also be a general feature for SCCs of different origins.

New insights into long non-coding RNAs in breast cancer: Biological functions and therapeutic prospects

Breast cancer (BC) has become one of the most common malignant tumors in the world, seriously endangering women's health and life. However, the underlying molecular mechanisms of BC remain unclear. Over the past decade, long non-coding RNAs (lncRNAs) were gradually discovered and appreciated to play pivotal regulatory role in the progression of BC. It has been demonstrated that lncRNAs are implicated in regulating plenty of biological phenomena including cell proliferation, apoptosis, invasion and metastasis by interacting with DNA, RNA or proteins. In addition to these, the function of lncRNAs in tumor resistance has increasingly attracted more attention. In this review, we summarized the emerging impact of lncRNAs on the occurrence and progression of human BC, specifically focusing on the functions and mechanisms of them, with the aim of exploring the potential value of lncRNAs as oncogenic drivers or tumor suppressors. Furthermore, the potential clinical application of lncRNAs as diagnostic biomarkers and therapeutic targets in BC was also discussed.

EZH2-Mediated microRNA-375 Upregulation Promotes Progression of Breast Cancer via the Inhibition of FOXO1 and the p53 Signaling Pathway

Breast cancer (BC) is the most common gynecologic tumor worldwide where aberrant expression of microRNAs (miRNAs) is frequently involved. Here, we evaluated the function of miR-375 on BC development and the molecules implicated. Differentially expressed genes between tumor and paired normal tissues from BC patients were screened out by microarray analyses. miR-375 was abundantly expressed in BC tissues and cells, and it was correlated with the poor prognosis of patients. Downregulation of miR-375 was introduced into BC cell lines MCF-7 and HCC1954, after which the viability, colony formation, migration, and invasion were suppressed, while the apoptosis of cells was increased, and the xenograft tumors in nude mice were reduced as well. EZH2 increased methylation and phosphorylation of signal transducer and activator of transcription 3 (STAT3) and increased transcription activity of miR-375, while miR-375 directly targeted FOXO1. Either overexpression of EZH2 or downregulation of FOXO1 blocked the functions of anti-miR-375 in cells and animals. FOXO1 was found as an activator of the p53 signaling pathway. This study showed that miR-375 is an important oncogene in BC. EZH2 is an upstream regulator of miR-375 through mediating the methylation of STAT3, while FOXO1 is a downstream target mRNA of miR-375 that activates the p53 signaling pathway to suppress BC development.

Knockdown of NIR Suppresses Breast Cancer Cell Proliferation via Promoting FOXO3

Background

Novel inhibitor of histone acetyltransferase repressor (NIR), a corepressor with a novel inhibitor of histone acetyltransferase (INHAT) activity, has been reported to be a negative modulator of p53 and a regulator of the cell cycle in cancer cells. However, the role of NIR in the progression of breast cancer remains elusive.

Materials and Methods

Oncomine database was used to analyze the mRNA levels and prognosis value of NIR in breast cancer. We performed loss-of-function and gain-of-function studies using lentivirus expressing shRNA targeting NIR, enhancer of zeste homolog 2 (EZH2) and forkhead box O3 (FOXO3) or lentivirus expressing NIR or FOXO3, respectively. Cell proliferation and colony formation assays were performed. Co-immunoprecipitation (Co-IP) and immunoprecipitation (IP) were performed to identify the interaction between NIR and polycomb repressive complex 2 (PRC2) subunits. ChIP assay was used to identify the enrichment of NIR, EZH2, H3K27ac and H3K27me3 at the FOXO3 promoter region and the regulation of H3K27 modification at the FOXO3 promoter by NIR.

Results

High levels of NIR expression were correlated with poor prognosis in breast cancer patients. Knockdown of NIR suppressed the proliferation of breast cancer cells. Mechanically, NIR was recruited by EZH2 to the promoter vicinity of FOXO3 via direct protein–protein interaction. Silencing NIR increased H3K27ac and decreased H3K27me3 levels at the FOXO3 promoter, resulting in enhancing FOXO3 expression. In accordance with this, growth inhibition of breast cancer cells caused by silencing of NIR could be reversed by FOXO3 knockdown.

Conclusion

NIR knockdown inhibited proliferation by switching the H3K27me3 and H3K27ac marks at the FOXO3 promoter to promote FOXO3 transcription, and this effect depends on the physical interaction between NIR and PRC2 in breast cancer cells. Our results suggest that NIR might be a potential target for breast cancer treatment.

LncRNA HOTAIR promotes breast cancer progression through regulating the miR-129-5p/FZD7 axis

Breast cancer is the most common malignancies worldwide. LncRNA HOX transcript antisense intergenic RNA (HOTAIR) has been shown to promote progression and metastasis of various cancers, including breast cancer. This reasearch aimed to investigate the downstream regulatory pathways of HOTAIR in breast cancer. The levels of HOTAIR and miR-129-5p were examined in breast cancer tissues and SKBR3 and MCF7 cells by quantitative real-time PCR (qRT-PCR). Cell proliferation was examined by Cell Counting Kit-8 (CCK-8) assay. Cell migration and invasion were estimated by transwell assay. Epithelial-to-mesenchymal transition (EMT)-related markers (E-cadherin, N-cadherin and Vimentin) were measured by Western blot assay. The expression of Frizzled 7 (FZD7) was detected using qRT-PCR or Western blot assay. Bioinformatics analysis, luciferase reporter assay or RNA Immunoprecipitation (RIP) assay was performed to explore the molecular mechanism of HOTAIR in breast cancer. Xenograft analysis was utilized to evaluate the tumor growth in vivo. HOTAIR and FZD7 were upregulated, while miR-129-5p was down-regulated in breast cancer tissues and cells. Knockdown of miR-129-5p reversed the effect of HOTAIR knockdown on cell proliferation, migration, invasion and EMT. FZD7 restored the inhibition of miR-129-5p on breast cancer progression. Furthermore, HOTAIR was a sponge of miR-129-5p and FZD7 was a target of miR-129-5p. Knockdown of HOTAIR inhibited the tumor growth in vivo. HOTAIR facilitated breast cancer progression by regulating the miR-129-5p/FZD7 axis, indicating that HOTAIR may be a potential biomarker and therapeutic target for breast cancer.

The Current State of Research Regarding the Role of Non-Coding RNAs in Cutaneous Squamous Cell Carcinoma

Skin cancers, including those of both both melanoma and non-melanoma subtypes, remain among the most common forms of human cancer. Non-melanoma skin cancers are typically further differentiated into the basal cell carcinoma and cutaneous squamous cell carcinoma (cSCC) categories. Current approaches to diagnosing and treating cSCC remain unsatisfactory, and the prognosis for patients with this disease is relatively poor. Recent advances in high-throughput sequencing have led to an increasingly robust understanding of the diversity of non-coding RNAs (ncRNAs) expressed in both physiological and pathological contexts. These ncRNAs include microRNAs, long ncRNAs, and circular RNAs, all of which have been found to play key functional roles and/or to have value as diagnostic biomarkers or therapeutic targets in a range of different disease contexts. The number of ncRNAs associated with cSCC continues to rise, and as such, there is clear value in comprehensively reviewing the functional roles of these molecules in this form of cancer in order to highlight future avenues for research and clinical development.

Downregulation of histone-lysine N-methyltransferase EZH2 inhibits cell viability and enhances chemosensitivity in lung cancer cells

Histone-lysine N-methyltransferase EZH2 (EZH2) is the principle component of the polycomb repressive complex 2 (PRC2)/embryonic ectoderm development protein-EZH2 complex, which promotes tumorigenesis by repressing transcription of tumor suppressor genes. EZH2 is considered a key marker in several types of cancer, such as colorectal and prostate cancer. However, the molecular mechanisms and clinical value of EZH2 in lung cancer have not yet been fully investigated. The aim of the present study was to investigate the functions of EZH2 in lung cancer progression and to determine whether treatment with an EZH2 inhibitor enhanced the chemosensitivity of lung cancer cells to cisplatin (CDDP). At the logarithmic growth phase, A549 cells were treated with a small interfering (si)RNA-EZH2, and cell viability was detected using an MTT assay. The degree of apoptosis and cell cycle were detected using flow cytometry. Cell migration and invasion were detected via wound healing and Transwell Matrigel assays. According to information from the Gene Expression Omnibus database, the results of the present study demonstrated that EZH2 was upregulated in lung cancer. Furthermore, overexpression of EZH2 was associated with poor patient prognosis, while EZH2 knockdown inhibited cell viability and migration, and enhanced apoptosis and chemosensitivity in a lung cancer cell line. EZH2 knockdown and treatment of A549 cells using EZH2 inhibitor elevated the inhibitory effects of CDDP on cell viability and apoptosis. Western blot and reverse transcription-quantitative PCR analyses were performed to assess the expression levels of relative protein and mRNA, respectively, in A549 cells treated with siRNA-EZH2 or with CDDP. Overall, the results of the present study demonstrated that high EZH2 expression was associated with poor prognosis, accompanied with a potential impairment of migration and viability in lung cancer cells. These findings suggest that EZH2 may act as a candidate molecular target for gene therapy, and treatment with EZH2 inhibitor may be used to increase chemosensitivity to CDDP agents in lung cancer.

Long Non-Coding RNA THOR Enhances the Stem Cell-Like Traits of Triple-Negative Breast Cancer Cells Through Activating β-Catenin Signaling

Background

The oncogenic roles of lncRNA THOR have been revealed in several tumors, however, its functions in breast cancer are still unclear.

Material/Methods

Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect THOR expression in clinical samples and the expression of stemness regulatory factors. ALDH1 assay and sphere-formation analysis were constructed to examine the stemness of cells. Cell viability assay was constructed to determine the cell proliferation capacity. In vitro RNA-RNA interaction and messenger RNA (mRNA) stability assays were performed to explore the mechanisms.

Results

THOR was overexpressed in triple-negative breast cancer (TNBC) compared to that in luminal A- and B-type breast cancer. THOR silencing reduced TNBC cell stemness, which was evident by the decreased sphere-formation ability, stemness marker expression and ALDH1 activity. Mechanistically, THOR directly bound to β-catenin mRNA, enhanced β-catenin mRNA stability and thus increased its expression. Furthermore, overexpression of β-catenin partially diminished THOR silencing-mediated inhibition on TNBC cell stemness.

Conclusions

This work proposes that THOR facilitates TNBC cell stemness through activating β-catenin signaling.

In silico analyses identify lncRNAs: WDFY3-AS2, BDNF-AS and AFAP1-AS1 as potential prognostic factors for patients with triple-negative breast tumors

BACKGROUND

Long non-coding RNAs (lncRNAs) are characterized as having 200 nucleotides or more and not coding any protein, and several been identified as differentially expressed in several human malignancies, including breast cancer.

METHODS

Here, we evaluated lncRNAs differentially expressed in triple-negative breast cancer (TNBC) from a cDNA microarray data set obtained in a previous study from our group. Using in silico analyses in combination with a review of the current literature, we identify three lncRNAs as potential prognostic factors for TNBC patients.

RESULTS

We found that the expression of WDFY3-AS2, BDNF-AS, and AFAP1-AS1 was associated with poor survival in patients with TNBCs. WDFY3-AS2 and BDNF-AS are lncRNAs known to play an important role in tumor suppression of different types of cancer, while AFAP1-AS1 exerts oncogenic activity.

CONCLUSION

Our findings provided evidence that WDFY3-AS2, BDNF-AS, and AFAP1-AS1 may be potential prognostic factors in TNBC development.

Long Non-Coding RNA HOTAIR in Breast Cancer Therapy

Breast cancer (BC) is the most common cancer type among women, and morbidity and mortality rates are still very high. Despite new innovative therapeutic approaches for all BC molecular subtypes, the discovery of new molecular biomarkers involved in tumor progression has been fundamental for the implementation of personalized treatment strategies and improvement of patient management. Many experimental studies indicate that long non-coding RNAs (lncRNAs) are strongly involved in BC initiation, metastatic progression, and drug resistance. In particular, aberrant expression of HOX transcript antisense intergenic RNA (HOTAIR) lncRNA plays an important role in BC contributing to its progression and represents a predictor of BC metastasis. For its proven prognostic value, HOTAIR could represent a potential therapeutic target in BC. In the present review, we summarize the role of HOTAIR in cancer progression and drug resistance, in particular in BC, and we illustrate the main approaches for silencing it.

The emerging role of the long non-coding RNA HOTAIR in breast cancer development and treatment

Despite considering vast majority of the transcribed molecules as merely noise RNA in the last decades, recent advances in the field of molecular biology revealed the mysterious role of long non-coding RNAs (lncRNAs), as a massive part of functional non-protein-coding RNAs. As a crucial lncRNA, HOX antisense intergenic RNA (HOTAIR) has been shown to participate in different processes of normal cell development. Aberrant overexpression of this lncRNA contributes to breast cancer progression, through different molecular mechanisms. In this review, we briefly discuss the structure of HOTAIR in the context of genome and impact of this lncRNA on normal human development. We subsequently summarize the potential role of HOTAIR overexpression on different processes of breast cancer development. Ultimately, the relationship of this lncRNA with different therapeutic approaches is discussed.

Long non-coding RNA HOTAIR functions as a competitive endogenous RNA to regulate PRAF2 expression by sponging miR-326 in cutaneous squamous cell carcinoma

Background

LncRNAs may exert a regulatory effect in tumorigenesis. Although the expression of lncRNA HOTAIR has been confirmed to be notably elevated in the tissues of CSCC, its biological mechanism in CSCC is still unknown.

Methods

HOTAIR expression level in CSCC cell lines was monitored via qRT-PCR. Then CCK-8 assay, Transwell assay and EdU assay were adopted to detect cell migration and proliferation. Meanwhile, through bioinformatics analysis and luciferase reporter gene detection, a new target of HOTAIR was identified. Additionally, Western blotting and RIP analysis were adopted to discuss the possible mechanism.

Results

HOTAIR expression in CSCC cell lines exhibited an obvious elevation. Cell function analysis revealed that HOTAIR overexpression remarkably facilitated CSCC cell migration, proliferation and EMT process, which were impeded by down-regulation of HOTAIR. Furthermore, HOTAIR competitively bound to miR-326, so as to positively modulate miR-326 expression.

Conclusions

These results present that HOTAIR, as a ceRNA, regulates PRAF2 expression by competitive binding to miR-326 during CSCC.

Long non-coding RNA-HOTAIR promotes the progression of sepsis by acting as a sponge of miR-211 to induce IL-6R expression

Sepsis remains the primary cause of death in intensive care units and multiple long non-coding RNAs (lncRNAs) have been demonstrated to be dysregulated in samples of patients with sepsis. However, whether lncRNA-HOTAIR is involved in the etiology of sepsis remains unclear. The aim of the present study was to investigate the role of HOTAIR in sepsis and to reveal the associated mechanisms. A bioinformatics analysis and dual-luciferase reporter assay was performed to evaluate the interaction between HOTAIR and miR-211, as well as miR-211 and IL-6R. An animal model of sepsis was established in mice via cecal ligation and puncture. Interferon (IFN)-γ, interleukin (IL)-6, IL-17, tumor necrosis factor (TNF)-α, IL-1β, IL-6 receptor (R), microRNA (miR)-211 and HOTAIR expression was measured using reverse transcription-quantitative PCR. Cellular proliferation and apoptosis of monocytes were assessed using cell counting kit-8 assay and flow cytometry, respectively. miR-211 was revealed to be targeted by HOTAIR and IL-6R. The expression of IFN-γ, IL-6, IL-17, TNF-α, IL-1β, IL-6R and HOTAIR was significantly upregulated in the septic mice, whereas miR-211 expression was downregulated. The overexpression of hox transcript antisense RNA (HOTAIR) and knockdown of miR-211 were associated with an increased expression of IFN-γ, IL-6, IL-17, TNF-α, IL-1β and IL-6R in monocytes, while the overexpression of miR-211 exhibited the opposite effect. HOTAIR overexpression and miR-211 knockdown significantly inhibited cellular proliferation and promoted monocyte apoptosis, whereas the overexpression of miR-211 exhibited the opposite effects in monocytes. Therefore, HOTAIR may promote the progression of sepsis by indirectly regulating the expression of IL-6R via miR-211.

Identification of competitive endogenous RNAs network in breast cancer

BACKGROUND

MiRNAs can regulate gene expression directly or indirectly, and long noncoding RNAs as competing endogenous RNA (ceRNAs) can bind to miRNAs competitively and affect mRNA expression. The ceRNA network is still unclear in breast cancer. In this study, a ceRNA network was constructed, and new treatment and prognosis targets and biomarkers for breast cancer were explored.

METHODS

A total of 1 096 cancer tissues and 112 adjacent normal tissues to cancer from the TCGA database were used to screen out significant differentially expressed mRNAs (DEMs), lncRNAs (DELs), and miRNAs (DEMis) to construct a ceRNA network. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were used to predict potential functions. Survival analysis was performed to predict which functions were significant for prognosis.

RESULTS

From the analysis, 2 139 DEMs, 1 059 DELs, and 84 DEMis were obtained. Targeting predictions for DEMis-DELs and DEMis-DEMs can yield 26 DEMs, 90 DELs, and 18 DEMis. We performed GO enrichment analysis, and the results showed that the upregulated DEMs were involved in nucleosomes, extracellular regions, and nucleosome assembly, while the downregulated DEMs were mainly involved in Z disk, muscle contraction, and structural constituents of muscle. KEGG pathway analysis was performed on all DEMs, and the pathways were enriched in retinol metabolism, steroid hormone biosynthesis, and tyrosine metabolism. Through survival analysis of the ceRNA network, we identified four DEMs, two DELs, and two DEMis that were significant for poor prognosis.

CONCLUSIONS

This study suggested that constructing a ceRNA network and performing survival analysis on the network could screen out new significant treatment and prognosis targets and biomarkers.

Interaction between 12p chromosomal abnormalities and Lnc-HOTAIR mediated pathway in acute myeloid leukemia

OBJECTIVES

To investigate the correlation of homeobox (HOX) transcript antisense RNA expression with clinicopathological features and the clinical prognosis of the patients with chromosome 12p abnormalities associated acute myeloid leukemia (AML). We also investigate the association of 12p chromosomal on the expression of HOTAIR, miRNA-193a, and c-kit gene as targeting genes for HOTAIR in AML.

METHODS

AML patients with 12p chromosomal abnormalities were recruited and compared to AML with other chromosomal abnormalities rather than 12p. The long noncoding RNA (lncRNA) "HOTAIR," miR-193a, and c-Kit genes expression were measured in bone marrow samples using Syber green based real-time polymerase chain reaction.

RESULTS

We found a significant difference for the expression levels of HOTAIR, c-kit, and miR-193a between 12p abnormalities associated AML and those without. The survival analysis revealed that patient's with low expression levels of HOTAIR and c-kit had significantly better survival and leukemia free survival. In contrast, miR-193a was associated with better overall survival but not leukemia free survival.

CONCLUSION

12p abnormalities associated AML were associated with worse prognosis. Our results proved that HOTAIR, miR-193a, and c-kit genes are independent prognostic predictors in 12p chromosomal associated AML; therefore it may represent a novel therapeutic application in AML in the future.

An eight-lncRNA signature predicts survival of breast cancer patients: a comprehensive study based on weighted gene co-expression network analysis and competing endogenous RNA network

PURPOSE

To identify a lncRNA signature to predict survival of breast cancer (BRCA) patients.

METHODS

A total of 1222 BRCA case and control datasets were downloaded from the TCGA database. The weighted gene co-expression network analysis of differentially expressed mRNAs was performed to generate the modules associated with BRCA overall survival status and further construct a hub on competing endogenous RNA (ceRNA) network. LncRNA signatures for predicting survival of BRCA patients were generated using univariate survival analyses and a multivariate Cox hazard model analysis and validated and characterized for prognostic performance measured using receiver operating characteristic (ROC) curves.

RESULTS

A prognostic score model of eight lncRNAs signature was identified as Prognostic score = (0.121 × EXP_AC007731.1) + (0.108 × EXP_AL513123.1) + (0.105 × EXP_C10orf126) + (0.065 × EXP_WT1-AS) + (- 0.126 × EXP_ADAMTS9-AS1) + (- 0.130 × EXP_SRGAP3-AS2) + (0.116 × EXP_TLR8-AS1) + (0.060 × EXP_HOTAIR) with median score 1.088. Higher scores predicted higher risk. The lncRNAs signature was an independent prognostic factor associated with overall survival. The area under the ROC curves (AUC) of the signature was 0.979, 0.844, 0.99 and 0.997 by logistic regression, support vector machine, decision tree and random forest models, respectively, and the AUCs in predicting 1- to 10-year survival were between 0.656 and 0.748 in the test dataset from TCGA database.

CONCLUSIONS

The eight-lncRNA signature could serve as an independent biomarker for prediction of overall survival of BRCA. The lncRNA-miRNA-mRNA ceRNA network is a good tool to identify lncRNAs that is correlated with overall survival of BRCA.

The Epigenome in Multiple Myeloma: Impact on Tumor Cell Plasticity and Drug Response

Multiple myeloma (MM) is a clonal plasma cell malignancy that develops primarily in the bone marrow (BM), where reciprocal interactions with the BM niche foster MM cell survival, growth, and drug resistance. MM cells furthermore reshape the BM to their own needs by affecting the different BM stromal cell types resulting in angiogenesis, bone destruction, and immune suppression. Despite recent advances in treatment modalities, MM remains most often incurable due to the development of drug resistance to all standard of care agents. This underscores the unmet need for these heavily treated relapsed/refractory patients. Disruptions in epigenetic regulation are a well-known hallmark of cancer cells, contributing to both cancer onset and progression. In MM, sequencing and gene expression profiling studies have also identified numerous epigenetic defects, including locus-specific DNA hypermethylation of cancer-related and B cell specific genes, genome-wide DNA hypomethylation and genetic defects, copy number variations and/or abnormal expression patterns of various chromatin modifying enzymes. Importantly, these so-called epimutations contribute to genomic instability, disease progression, and a worse outcome. Moreover, the frequency of mutations observed in genes encoding for histone methyltransferases and DNA methylation modifiers increases following treatment, indicating a role in the emergence of drug resistance. In support of this, accumulating evidence also suggest a role for the epigenetic machinery in MM cell plasticity, driving the differentiation of the malignant cells to a less mature and drug resistant state. This review discusses the current state of knowledge on the role of epigenetics in MM, with a focus on deregulated histone methylation modifiers and the impact on MM cell plasticity and drug resistance. We also provide insight into the potential of epigenetic modulating agents to enhance clinical drug responses and avoid disease relapse.

Research progresses in roles of LncRNA and its relationships with breast cancer

Some progresses have been made in research of long non-coding RNA (hereunder referred to as LncRNA) related to breast cancer. Lots of data about LncRNA transcription concerning breast cancer have been obtained from large-scale omics research (e.g. transcriptomes and chips). Some LncRNAs would become indices for detecting breast cancer and judging its development and prognosis. LncRNAs may affect genesis and development of breast cancer in multiple ways. Perhaps they could develop into potential targets for treating breast cancer if they are carcinogenic. Like those from other studies of breast cancer, many data gained from omics research remain to be validated by much experimental work. For instance, it is still necessary to demonstrate reliability of LncRNAs as indices for diagnosing breast cancer and judging its prognosis (particularly for various subtypes of breast cancer), effectiveness and feasibility of these genes for treating breast cancer as targets. In this paper, recent years’ literatures about LncRNAs which are related to breast cancer are summarized and sorted out to review the research progresses in relationships between LncRNAs and breast cancer.