MIAT lncRNA is overexpressed in breast cancer and its inhibition triggers senescence and G1 arrest in MCF7 cell line

Novel role of lncRNAs regulatory network in papillary thyroid cancer

Papillary thyroid cancer (PTC) is the most common endocrine malignancy. The incidence of PTC has increased annually worldwide. Thus, PTC diagnosis and treatment attract more attention. Noncoding RNAs (lncRNAs) play crucial roles in PTC progression and act as prognostic biomarkers. Moreover, microRNAs (miRNAs) and epithelial-mesenchymal transition (EMT)-associated proteins have potential biomarkers for diagnosing and treating PTC. However, the correlation of lncRNAs with miRNAs and EMT-associated proteins needs further clarification. The present review highlights the recent advances of lncRNAs in PTC. We significantly summarized the two molecular regulatory mechanisms in PTC progress, including lncRNAs-miRNAs-protein signaling axes and lncRNAs-EMT pathways. This review will help our understanding of the association between lncRNAs and PTC and may assist us in evaluating the prognosis for PTC patients. Taken together, targeting the lncRNAs regulatory network has promising applications in diagnosing and treating PTC.

Expression, Functional Polymorphism, and Diagnostic Values of MIAT rs2331291 and H19 rs217727 Long Non-Coding RNAs in Cerebral Ischemic Stroke Egyptian Patients

Cerebral ischemic stroke (CIS) is a severe cerebral vascular event. This research aimed to evaluate the role of single-nucleotide polymorphisms (SNPs) of the lncRNAs MIAT rs2331291 and H19 rs217727 and epigenetic methylation in the expression patterns of serum lncRNA H19 in CIS Egyptian patients. It included 80 CIS cases and 40 healthy subjects. Serum MIAT expression levels decreased, whereas serum H19 expression levels increased among CIS compared to controls. For MIAT rs2331291, there were significant differences in the genotypic and allelic frequencies between the CIS and healthy subjects at p = 0.02 and p = 0.0001, respectively. Our findings illustrated a significantly increased MIAT T/T genotype frequency in hypertensive CIS compared to non-hypertensive CIS at p = 0.004. However, H19 rs217727 gene frequency C/C was not significantly higher in non-hypertensive CIS than in hypertensive CIS. The methylation of the H19 gene promoter was significantly higher in CIS patients compared to healthy subjects. The level of MIAT was positively correlated with serum H19 in CIS. Receiver operating characteristics (ROC) analysis revealed that serum MIAT and H19 have a high diagnostic potential for distinguishing CIS subjects from healthy ones. In conclusion, the MIAT-rs2331291 polymorphism might serve as a novel potential indicator of CIS.

Bridging Pyroptosis and Immunity: A Comprehensive Study of the Pyroptosis-Related Long Non-Coding RNA Signature in Breast Cancer

Breast cancer continuously poses serious clinical challenges to human health due to its intrinsic heterogenicity and evolving drug resistance. Recently, increasing evidence has shown that pyroptosis, known as a programmed and inflammatory form of cell death, participates in tumorigenesis, progression, and remodeling of the tumor immune microenvironment (TIME). However, a comprehensive insight into pyroptosis-related signatures for breast cancer remains elusive. The current study established a pyroptosis-related lncRNA signature using transcriptome data and corresponding clinical information from The Cancer Genome Atlas (TCGA). Pyroptosis-related gene clusters, the associated differential expression in breast cancer patients' subtypes, and the potential mechanisms were all discussed. This integrative analysis revealed a unique signature underpinning the dichotomy of breast cancer progression and survival outcomes. Interestingly, the pyroptosis-related lncRNA signature was revealed as closely intertwined with the TIME. A correlation was established between the pyroptosis-related LncRNA signature and the TIME, underlying the mutual effect between pyroptosis and the immune responses implicated in breast cancer. The findings in this work underline the critical role exerted by pyroptosis in breast cancer, providing new insights into disease progression, prognosis, and therapeutic potential. This work has been poised to provide new avenues for personalized, immune-based cancer therapeutics by enhancing our understanding of pyroptosis in breast cancer.

Evaluation of the Potential Diagnostic Role of the Lnc-MIAT, miR-29a-3p, and FOXO3a ceRNA Networks as Noninvasive Circulatory Bioindicator in Ductal Carcinoma Breast Cancer

Background

Over the last few decades, tremendous progress has been achieved in the early detection and treatment of breast cancer (BC). However, the prognosis remains unsatisfactory, and the underlying processes of carcinogenesis are still unclear. The purpose of this research was to find out the relationship between myocardial infarction-associated transcript (MIAT), FOXO3a, and miRNA29a-3p and evaluated the expression levels in patients compare with control and their potential as a noninvasive bioindicator in whole blood in BC.

Methods

Whole blood and BC tissue are taken from patients before radiotherapy and chemotherapy. Total RNA was extracted from BC tissue and whole blood to synthesize complementary DNA (cDNA). The expression of MIAT, FOXO3a, and miRNA29a-3p was analyzed by the quantitative reverse transcription-polymerase chain reaction (RT-qPCR) method and the sensitivity and specificity of them were determined by the receiver operating characteristic (ROC) curve. Bioinformatics analysis was used to understand the connections between MIAT, FOXO3a, and miRNA29a-3p in human BC to develop a ceRNA (competitive endogenous RNA) network.

Results

We identified that in ductal carcinoma BC tissue and whole blood, MIAT and FOXO3a were more highly expressed, whereas miRNA29a-3p was lower compared with those in nontumor samples. There was a positive correlation between the expression levels of MIAT, FOXO3a, and miRNA29a-3p in BC tissues and whole blood. Our results also proposed miRNA29a-3p as a common target between MIAT and FOXO3a, and we showed them as a ceRNA network.

Conclusions

This is the first study that indicates MIAT, FOXO3a, and miRNA29a-3p as a ceRNA network, and their expression was analyzed in both BC tissue and whole blood. As a preliminary assessment, our findings indicate that combined levels of MIAT, FOXO3a, and miR29a-3p may be considered as potential diagnostic bioindicator for BC.

LncRNA PNKY Is Upregulated in Breast Cancer and Promotes Cell Proliferation and EMT in Breast Cancer Cells

Long non-coding RNAs (lncRNAs) are known to be important regulators in different cellular processes and are implicated in various human diseases. Recently, lncRNA PNKY has been found to be involved in pluripotency and differentiation of embryonic and postnatal neural stem cells (NSCs); however, its expression and function in cancer cells is still unclear. In the present study, we observed the expression of PNKY in various cancer tissues, including brain, breast, colorectal, and prostate cancers. In particular, we demonstrated that lncRNA PNKY was significantly upregulated in breast tumors, especially high-grade tumors. Knock down experiments indicated that the suppression of PNKY in breast cancer cells could restrict their proliferation by promoting apoptosis, senescence, and cell cycle disruption. Moreover, the results demonstrated that PNKY may play a crucial role in the cell migration of breast cancer cells. We further found that PNKY may trigger EMT in breast cancer cells by upregulating miR-150 and restricting the expression of Zeb1 and Snail. This study is the first to provide new evidence on the expression and biological function of PNKY in cancer cells and its potential contribution to tumor growth and metastasis.

Silencing of long noncoding RNA MIAT inhibits the viability and proliferation of breast cancer cells by promoting miR-378a-5p expression

Myocardial infarction–associated transcript (MIAT) is a long noncoding RNA that plays a critical role in a variety of diseases. Accordingly, this study probed into the possible interaction mechanism between MIAT and miR-378a-5p in breast cancer. Concretely, MIAT and miR-378a-5p expressions in breast cancer tissues and cells were measured. After transfection with siMIAT and miR-378a-5p inhibitor, the viability and proliferation of breast cancer cells were examined by cell counting kit-8 and colony formation assays. The expressions of apoptosis-related proteins were detected. According to the results, MIAT was highly expressed in breast cancer tissues and cells. MIAT silencing could decrease Bcl-2 expression, viability, and proliferation of breast cancer cells and increase the expressions of cleaved caspase-3 and Bax. MIAT and miR-378a-5p could directly bind to each other, and MIAT silencing promoted the expression of miR-378a-5p. miR-378a-5p expression was low in breast cancer tissues. The miR-378a-5p inhibitor enhanced the viability and proliferation of breast cancer cells and partially reversed the effects of MIAT silencing on the breast cancer cells. In conclusion, MIAT silencing inhibits the viability and proliferation of breast cancer cells by promoting miR-378a-5p, indicating the potential of MIAT as a new target for the treatment of breast cancer.

BRWMC: Predicting lncRNA-disease associations based on bi-random walk and matrix completion on disease and lncRNA networks

Many experiments have proved that long non-coding RNAs (lncRNAs) in humans have been implicated in disease development. The prediction of lncRNA-disease association is essential in promoting disease treatment and drug development. It is time-consuming and laborious to explore the relationship between lncRNA and diseases in the laboratory. The computation-based approach has clear advantages and has become a promising research direction. This paper proposes a new lncRNA disease association prediction algorithm BRWMC. Firstly, BRWMC constructed several lncRNA (disease) similarity networks based on different measurement angles and fused them into an integrated similarity network by similarity network fusion (SNF). In addition, the random walk method is used to preprocess the known lncRNA-disease association matrix and calculate the estimated scores of potential lncRNA-disease associations. Finally, the matrix completion method accurately predicts the potential lncRNA-disease associations. Under the framework of leave-one-out cross-validation and 5-fold cross-validation, the AUC values obtained by BRWMC are 0.9610 and 0.9739, respectively. In addition, case studies of three common diseases show that BRWMC is a reliable method for prediction.

Cell cycle related long non-coding RNAs as the critical regulators of breast cancer progression and metastasis

Cell cycle is one of the main cellular mechanisms involved in tumor progression. Almost all of the active molecular pathways in tumor cells directly or indirectly target the cell cycle progression. Therefore, it is necessary to assess the molecular mechanisms involved in cell cycle regulation in tumor cells. Since, early diagnosis has pivotal role in better cancer management and treatment, it is required to introduce the non-invasive diagnostic markers. Long non-coding RNAs (LncRNAs) have higher stability in body fluids in comparison with mRNAs. Therefore, they can be used as efficient non-invasive markers for the early detection of breast cancer (BCa). In the present review we have summarized all of the reported lncRNAs involved in cell cycle regulation in BCa. It has been reported that lncRNAs mainly affect the cell cycle in G1/S transition through the CCND1/CDK4-6 complex. Present review paves the way of introducing the cell cycle related lncRNAs as efficient markers for the early detection of BCa.

The LncRNA MIAT is identified as a regulator of stemness-associated transcript in glioma

BACKGROUND

Myocardial infarction-associated transcript (MIAT) is a long non-coding RNA (lncRNA) with altered expression in different diseases and malignancies. In this study, the potential expression and function of lncRNA MIAT in intuition and progression of brain cancer was investigated.

METHODS AND RESULTS

At first, TCGA data analysis demonstrated that lncRNA MIAT is significantly upregulated in various malignancies, especially its expression is dramatically elevated in brain tumors. In line with the data, we further evaluated the expression of MIAT in a series of brain tumor tissue, and our results revealed that the expression of MIAT was noticeably overexpressed in glioblastoma (p = < 0.0001). We further found that the expression of MIAT was markedly upregulated in low-grade brain tumors rather than high-grade ones. To further investigate the biological function of MIAT in brain cancer cells, its expression was suppressed by si-RNA-mediated knocking down. Inhibition of MIAT resulted in reduced proliferation of brain tumor cells followed by cell cycle arrest at the G1 phase, and significant induction of apoptosis, and senescence, but limited the migration ability and epithelial-mesenchymal-transition (EMT). Moreover, knocking-down of MIAT reduced the expression of stemness factors, followed by upregulation of their downstream miRNAs (micro RNAs), let-7a-5p, and miR-29b-3p.

CONCLUSIONS

Altogether, our data demonstrated that lncRNA MIAT could control proliferation, migration, and metastasis of brain cancer cells via regulating the Nanog/ Sox2 / let-7a-5p / miR-29b-3p axis. This data could introduce lncRNA MIAT as a novel oncogene in brain cancer pathogenesis.

The effect of iron sulfate nanoparticles and their fortified bread on Wistar rats and human cell lines

BACKGROUND

Ferrous sulfate nanoparticles (FSNPs) were synthesized and characterized to mitigate the undesirable effects of ferrous sulfate bulk particles (FSBPs) as a supplement or fortificant in health/food industries.

METHODS

The toxicity of FSNPs and FSBPs was evaluated against AGS, PLC/PRF/5, and HGF1-PI 1 cell lines. Then, Wistar rats were fed three levels of FSNPs and FSBPs fortified-bread. Growth performance, hematological parameters, and histopathological changes in treated rats were assessed after 21 days.

RESULTS

High concentrations of FSNPs (3.125 and 6.25 mM) increased the necrosis of AGS cells. A low level of FSNPs (1.57 mM) did not affect the viability of cells after 72 h. Fibroblasts did not show apoptosis and necrosis after exposing 1.57 mM of FSNPs. In rats, 9 mg elemental iron of FSNPs/day enhanced hemoglobin, PCV, and ferritin values and increased the body weight gain (p < 0.05). FSNPs fortified-bread induced no clinical symptom or histopathological lesion in rats.

CONCLUSION

FSNPs affect cells in a dose-dependent manner. The results indicate that FSNPs at the low level do not have adverse effects on normal fibroblasts and rats. Significant weight gain in rats having a low level of FSNPs compared to the FSBPs indicates the negligible toxicity of FSNPs at low concentrations.

Emerging Role of Non-Coding RNAs in Senescence

Senescence is defined as a gradual weakening of functional features of a living organism. Cellular senescence is a process that is principally aimed to remove undesirable cells by prompting tissue remodeling. This process is also regarded as a defense mechanism induced by cellular damage. In the course of oncogenesis, senescence can limit tumor progression. However, senescence participates in the pathoetiology of several disorders such as fibrotic disorders, vascular disorders, diabetes, renal disorders and sarcopenia. Recent studies have revealed contribution of different classes of non-coding RNAs in the cellular senescence. Long non-coding RNAs, microRNAs and circular RNAs are three classes of these transcripts whose contributions in this process have been more investigated. In the current review, we summarize the available literature on the impact of these transcripts in the cellular senescence.

Genetic and RNA-related molecular markers of trastuzumab-chemotherapy-associated cardiotoxicity in HER2 positive breast cancer: a systematic review

Cancer-therapy related cardiotoxicity (CTRCT) is a significant and frequent complication of monoclonal antibody directed therapy, especially Trastuzumab, for human epidermal growth factor receptor 2 (HER2) overexpressing breast cancers. Reliable, clinically available molecular predictive markers of CTRCT have not yet been developed. Identifying specific genetic variants and their molecular markers, which make the host susceptible to this complication is key to personalised risk stratification. A systematic review was conducted until April 2021, using the Medline, Embase databases and Google Scholar, to identify studies genetic and RNA-related markers associated with CTRCT in HER2 positive breast cancer patients. So far, researchers have mainly focused on HER2 related polymorphisms, revealing codons 655 and 1170 variants as the most likely SNPs associated with cardiotoxicity, despite some contradictory results. More recently, new potential genetic markers unrelated to the HER2 gene, and linked to known cardiomyopathy genes or to genes regulating cardiomyocytes apoptosis and metabolism, have been detected. Moreover, microRNAs are gaining increasing recognition as additional potential molecular markers in the cardio-oncology field, supported by encouraging preliminary data about their relationship with cardiotoxicity in breast cancers. In this review, we sought to synthesize evidence for genetic variants and RNA-related molecular markers associated with cardiotoxicity in HER2-positive breast cancer.

LncRNA NORAD promotes the progression of myocardial infarction by targeting the miR-22-3p/PTEN axis

NORAD is a newly identified long non-coding RNA (lncRNA) that plays an important role in cancers. NORAD has been found to be highly expressed in the mouse model of acute myocardial infarction (AMI). However, the role of NORAD in the regulation of AMI remains unknown. In the present study, we aimed to investigate the function of NORAD in AMI and explore the potential regulatory mechanisms. A mouse model of AMI was established and NORAD was knocked-down. The infarcted size of heart tissues and the cardiac function were evaluated. In addition, two cardiomyocyte cell lines were treated with hypoxia/re-oxygenation (H/R) to mimic AMI . Luciferase reporter assay, RNA pull-down assay, fluorescence hybridization, qRT-PCR, and western blot analysis were performed. Apoptotic cells and the levels of L-lactate dehydrogenase (LDH) and malondialdehyde (MDA) were detected. Our results show that downregulation of NORAD efficiently attenuates heart damage in the AMI mouse model. NORAD interacts with miR-22-3p. Knock-down of NORAD inhibits H/R-induced cell apoptosis and reduces LDH and MDA levels, while its effects are abolished by miR-22-3p inhibitor. MiR-22-3p interacts with PTEN and inhibits its expression. Overexpression of miR-22-3p inhibits H/R-induced cell apoptosis and reduces LDH and MDA levels, while its effects are abolished by overexpression of PTEN. Finally, overexpression of NORAD inhibits the AKT/mTOR signaling pathway, and its effects are attenuated by overexpression of miR-22-3p. Taken together, our study reveals that NORAD promotes the progression of AMI by regulating the miR-22-3p/PTEN axis, and the AKT/mTOR signaling may also be involved in the regulatory processes.

An 11-Gene Signature Based on Treatment Responsiveness Predicts Radiation Therapy Survival Benefit Among Breast Cancer Patients

Purpose

We developed a strategy of building prognosis gene signature based on clinical treatment responsiveness to predict radiotherapy survival benefit in breast cancer patients.

Methods and Materials

Analyzed data came from the public database. PFS was used as an indicator of clinical treatment responsiveness. WGCNA was used to identify the most relevant modules to radiotherapy response. Based on the module genes, Cox regression model was used to build survival prognosis signature to distinguish the benefit group of radiotherapy. An external validation was also performed.

Results

In the developed dataset, MEbrown module with 534 genes was identified by WGCNA, which was most correlated to the radiotherapy response of patients. A number of 11 hub genes were selected to build the survival prognosis signature. Patients that were divided into radio-sensitivity group and radio-resistant group based on the signature risk score had varied survival benefit. In developed dataset, the 3-, 5-, and 10-year AUC of the signature were 0.814 (CI95%: 0.742–0.905), 0.781 (CI95%: 0.682–0.880), and 0.762 (CI95%: 0.626–0.897), respectively. In validation dataset, the 3- and 5-year AUC of the signature were 0.706 (CI95%: 0.523–0.889) and 0.743 (CI95%: 0.595–0.891). The signature had higher predictive power than clinical factors alone and had more clinical prognosis efficiency. Functional enrichment analysis revealed that the identified genes were mainly enriched in immune-related processes. Further immune estimated analysis showed the difference in distribution of immune micro-environment between radio-sensitivity group and radio-resistant group.

Conclusions

The 11-gene signature may reflect differences in tumor immune micro-environment that underlie the differential response to radiation therapy and could guide clinical-decision making related to radiation in breast cancer patients.

Prognostic significance of long non-coding RNA five prime to XIST in various cancers

BACKGROUND

To observe the clinicopathological and prognostic value of long non-coding RNA five prime to X inactive specific transcript (lncFTX) in multiple tumors.

METHODS

Eligible studies for lncFTX were identified by searching PubMed, Embase, Web of Science and Cochrane Library databases from inception to December 01, 2020. Stata 12.0 software was used to calculate the odds ratio (OR)/hazard ratio (HR) and 95% confidence interval (95% CI). We used The Cancer Genome Atlas (TCGA) dataset to further investigate the differential expression and prognostic value of lncFTX.

RESULTS

We included 11 studies involving a total of 1633 patients. The results showed that the expression of lncFTX was positively associated with advanced TNM stage (III-IV versus I-II) (OR = 2.30, 95% CI: 1.74-3.03, P < 0.05), lymph nodes metastasis (OR = 3.01, 95% CI: 2.00-4.52, P < 0.05), distant metastasis (OR = 3.68, 95% CI: 2.13-6.34, P < 0.05), and cancer mortality (HR = 1.83, 95% CI: 1.20-2.81, P < 0.05). However, the expression of lncFTX was not associated with tumor differentiation (poor differentiation versus well or moderate differentiation) and vessel invasion of cancer. Subgroup analysis showed that the higher lncFTX expression was associated with shorter overall survival in cancer patients, regardless of the sample size and cancer type. No publication bias was found, and the sensitivity analysis results suggested that the main findings were robust. Elevated expression and prognostic significance of FTX were confirmed using TCGA dataset.

CONCLUSIONS

This study found that the expression of lncFTX was positively associated with advanced tumor node metastasis (TNM) stage, lymph nodes, distant metastasis and, cancer mortality, suggesting that lncFTX might be a potential prognostic biomarker for tumors.

LncRNA MIAT Services as a Noninvasive Biomarker for Diagnosis and Correlated with Immune Infiltrates in Breast Cancer

Background

Myocardial infarction associated transcript (MIAT) is identified as a long chain non-coding RNA (lncRNA), which was associated with myocardial infarction susceptibility. While intense efforts have been made to elucidate the relationship between MIAT and carcinogenesis, the tumor immunoreaction of MIAT remains elusive. Thus, this study aimed to investigate the role of MIAT in the immunoregulation of breast cancer (BC) and further explore the better clinical significance.

Methods

The differential expression of MIAT between BC and normal/adjacent tissues was compared using Wilcoxon rank sum test. The diagnostic and prognostic values of elevated MIAT expression in BC tissues were unveiled via receiver operating characteristic (ROC) analysis and KM-plotter analysis. Limma and edgeR package were used to identify differentially expressed genes (DEGs) and microRNAs (DEMs) from TCGA database respectively. A co-expression dataset was constructed to comprehensively understand the relationship between MIAT and DEGs based on the Pearson correlation coefficient. Furthermore, GO and KEGG analyses were conducted to predict the potential functions of MIAT. We next intersected immune-related genes (IRGs) from ImmPort database with MIAT-co-expressed genes to obtain MIAT-co-expressed IRGs, in order to construct MIAT-microRNA (miRNA)-mRNA network. And the correlation between MIAT and tumor-infiltrating immune cells (TICs) and immunophenoscore (IPS) analysis was analyzed by TIMER and CIBERSORT. Finally, the reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) was used to detect the expression profiles of MIAT in serum samples.

Results

The expression levels of MIAT were notably higher in BC than in normal or adjacent tissues. And MIAT expression could be used as a prognostic indicator of mortality risk in patients with BC in different aspects. Moreover, the enrichment analyses suggested that MIAT was strongly involved in BC immune response. In addition, TIMER database and CIBERSORT analyses indicated that MIAT was significantly correlated with 13 types of TICs (B cells, dendritic cells, neutrophils, CD8 T cells, CD4 memory resting T cells, CD4 memory activated T cells, gamma delta T cells, M1 macrophages, plasma cells, activated NK cells, monocytes, M2 macrophages, activated mast cells). Simultaneously, the IPS analysis implied that the higher the MIAT expression, the better the immunotherapy effect. The ROC curve analysis showed that the area under the curve (AUC) value of MIAT was 0.86 (sensitivity = 87.80%, specificity = 75.61%). And the high MIAT expression in serum was positive related to TNM stage (P = 0.032) and lymph node metastasis (P = 0.028).

Conclusion

MIAT may be a valuable noninvasive diagnostic biomarker for BC and is associated with tumor-infiltrating immune cells in tumor microenvironment, suggesting MIAT as a potential target for future treatment of BC.

Divergent regulation of lncRNA expression by ischemia in adult and aging mice

Elderly patients have increased susceptibility to acute kidney injury (AKI). Long noncoding RNAs (lncRNA) are key regulators of cellular processes, and have been implicated in both aging and AKI. Our aim was to study the effects of aging and ischemia-reperfusion injury (IRI) on the renal expression of lncRNAs. Adult and old (10- and 26-30-month-old) C57BL/6 N mice were subjected to unilateral IRI followed by 7 days of reperfusion. Renal expression of 90 lncRNAs and mRNA expression of injury, regeneration, and fibrosis markers was measured by qPCR in the injured and contralateral control kidneys. Tubular injury, regeneration, and fibrosis were assessed by histology. Urinary lipocalin-2 excretion was increased in old mice prior to IRI, but plasma urea was similar. In the control kidneys of old mice tubular cell necrosis and apoptosis, mRNA expression of kidney injury molecule-1, fibronectin-1, p16, and p21 was elevated. IRI increased plasma urea concentration only in old mice, but injury, regeneration, and fibrosis scores and their mRNA markers were similar in both age groups. AK082072 and Y lncRNAs were upregulated, while H19 and RepA transcript were downregulated in the control kidneys of old mice. IRI upregulated Miat, Igf2as, SNHG5, SNHG6, RNCR3, Malat1, Air, Linc1633, and Neat1 v1, while downregulated Linc1242. LncRNAs H19, AK082072, RepA transcript, and Six3os were influenced by both aging and IRI. Our results indicate that both aging and IRI alter renal lncRNA expression suggesting that lncRNAs have a versatile and complex role in aging and kidney injury. An Ingenuity Pathway Analysis highlighted that the most downregulated H19 may be linked to aging/senescence through p53.

Abnormal Long Non-Coding RNAs Expression Patterns Have the Potential Ability for Predicting Survival and Treatment Response in Breast Cancer

Abnormal long non-coding RNAs (lncRNAs) expression has been documented to have oncogene or tumor suppressor functions in the development and progression of cancer, emerging as promising independent biomarkers for molecular cancer stratification and patients’ prognosis. Examining the relationship between lncRNAs and the survival rates in malignancies creates new scenarios for precision medicine and targeted therapy. Breast cancer (BRCA) is a heterogeneous malignancy. Despite advances in its molecular classification, there are still gaps to explain in its multifaceted presentations and a substantial lack of biomarkers that can better predict patients’ prognosis in response to different therapeutic strategies. Here, we performed a re-analysis of gene expression data generated using cDNA microarrays in a previous study of our group, aiming to identify differentially expressed lncRNAs (DELncRNAs) with a potential predictive value for response to treatment with taxanes in breast cancer patients. Results revealed 157 DELncRNAs (90 up- and 67 down-regulated). We validated these new biomarkers as having prognostic and predictive value for breast cancer using in silico analysis in public databases. Data from TCGA showed that compared to normal tissue, MIAT was up-regulated, while KCNQ1OT1, LOC100270804, and FLJ10038 were down-regulated in breast tumor tissues. KCNQ1OT1, LOC100270804, and FLJ10038 median levels were found to be significantly higher in the luminal subtype. The ROC plotter platform results showed that reduced expression of these three DElncRNAs was associated with breast cancer patients who did not respond to taxane treatment. Kaplan–Meier survival analysis revealed that a lower expression of the selected lncRNAs was significantly associated with worse relapse-free survival (RFS) in breast cancer patients. Further validation of the expression of these DELncRNAs might be helpful to better tailor breast cancer prognosis and treatment.

Identification of Differentially Expressed Plasma lncRNAs As Potential Biomarkers for Breast Cancer

BACKGROUND

Breast cancer is the most common malignant tumor in women and is not easy to diagnose. Increasing evidence has underscored that long non-coding RNAs (lncRNAs) play important regulatory roles in the occurrence and progression of many cancers, including breast cancer. We aimed to identify lncRNAs in plasma as potential biomarkers for breast cancer.

PATIENTS AND METHODS

We analyzed the Gene Expression Omnibus (GEO) datasets GSE22820, GSE42568, and GSE65194 to identify the common differential genes between cancer tissues and adjacent tissues. Then 14 lncRNAs were identified among the common differential genes and validated by using real-time quantitative polymerase chain reaction in 92 patients with breast cancer and 100 healthy controls. Receiver operating characteristic (ROC) curves were constructed to evaluate their diagnostic value for breast cancer.

RESULTS

Integrated analysis of the GEO datasets identified three significantly upregulated and 11 downregulated lncRNAs in breast cancer tissues. Compared with healthy controls, MIAT was significantly upregulated in breast cancer patient plasma, and LINC00968 and LINC01140 were significantly downregulated. ROC curve analysis suggested that these three lncRNAs can discriminate breast cancer from healthy individual with high specificity and sensitivity.

CONCLUSION

This research identified three differentially expressed lncRNAs in breast cancer patient plasma. Our data suggest that these three lncRNAs can be used as potential diagnostic biomarkers of breast cancer.

LINC01410 accelerated the invasion and proliferation of osteosarcoma by sponging miR-3128

Increasing evidence has shown that lncRNAs are closely correlated with cell apoptosis, autophagy and progression. However, the role of LINC01410 in osteosarcoma has not been verified. We determined that LINC01410 was overexpressed in osteosarcoma specimens and cell lines. The expression of LINC01410 was upregulated in 22 osteosarcoma patients (22/30, 73%) compared to control normal samples. Ectopic expression of LINC01410 promoted the osteosarcoma cell cycle, proliferation and invasion. Overexpression of LINC01410 induced N-cadherin and Vimentin expression and inhibited E-cadherin expression in osteosarcoma cells. LINC01410 acted as a sponge for miR-3128. The results showed that miR-3128 overexpression decreased the luciferase activity of WT-LINC01410 but not mut-LINC01410 in MG-63 cells. Upregulation of LINC01410 expression suppressed miR-3128 expression in MG-63 cells. Moreover, LINC01410 overexpression increased osteosarcoma cell invasion and growth by modulating miR-3128. These data indicated that LINC01410 acted as an oncogene in osteosarcomagenesis and might be a potential new strategy for osteosarcoma treatment.

Myocardial Infarction Associated Transcript (MIAT): Review of its impact in the tumorigenesis

Myocardial Infarction Associated Transcript (MIAT) is a non-coding transcript which is located on chromosome 22q12.1. This lncRNA can regulate expression of genes at both transcriptional and post-transcriptional stages. It has been firstly recognized as a susceptibility locus for myocardial infarction. Subsequently, its role in the development of several human cancers has been acknowledged. Numerous researches have reported the impact of MIAT silencing on the reduction of cell viability, proliferation and invasion while enhancement of cellular senescence and apoptosis. Consistently, investigations in the xenograft models have verified MIAT role in the promotion of tumor growth. Numerous microRNAs such as miR-214, miR-22-3p, miR-520d-3p, miR-203a, miR-29a-3p, miR-141, miR-150, miR-302, miR-29, and miR-155-5p have functional interactions with this lncRNA. Moreover, dysregulation of MIAT has been associated with abnormal activity of numerous cancer-related signaling cascades such as Hippo, PI3K/Akt/c-Met and Wnt/β-catenin. In the current review, we explain the role of MIAT in the cancer evolution based on the outcomes of in vitro, in vivo and clinical studies.

LncRNA MIAT correlates with immune infiltrates and drug reactions in hepatocellular carcinoma

Long non-coding RNA (lncRNA) is a kind of important molecules involved in the formation of immune landscape in tumor microenvironment. However, there are few studies on the relationship between lncRNA and immunomodulatory regulation of hepatocellular carcinoma (HCC). In this study, we combined with single cell transcriptome sequencing and TCGA data to analyze the relationship between lncRNA MIAT and immune cells in HCC. TIMER database analysis indicated that the expression of MIAT in HCC was negatively correlated with tumor purity, positively correlated with the number of immune cells such as B cells, T lymphocytes and macrophages, and positively correlated with the expression of immune checkpoint molecules such as PD-1, PD-L1 and CTLA4. Analysis of single cell sequencing data of immune cells in HCC showed that MIAT was mainly distributed in tumor, and enriched in FOXP3⁺CD4⁺T cells and PDCD1⁺CD8⁺, GZMK⁺CD8⁺T cells, indicating that MIAT may be involved in the immune escape process of HCC. Besides, through the construction of transcription factor (TF) regulatory network, MIAT-TF-mRNA, we found that the interaction of MIAT and TFs may affect the immune microenvironment of LIHC by regulating the expression of target genes JAK2, SLC6A6, KCND1, MEIS3 or RIN1; LncMAP and CARE analysis showed that MIAT was highly related to the sensitivity of many anticancer drugs, especially sorafenib. In addition, the effect of MIAT on PD-L1 and its relationship with sorafinib were verified in clinical specimens and cells. This study made a meaningful attempt to reveal the immune escape mechanism and to find the effectiveness of targeted drugs in patients with HCC.

LINC00689 induces gastric cancer progression via modulating the miR-338-3p/HOXA3 axis

BACKGROUND

LINC00689 acts one critical regulatory role in several tumors. However, the functional, regulatory mechanism and expression of LINC00689 remains unknown in gastric cancer.

METHODS

LINC00689 and miR-338-3p levels were determined using a quantitative reverse transcriptase-polymerase chain reaction analysis and an enzyme-linked immunoassay and a cell-counting kit-8 assay were utilized to detect interleukin (IL)-8, IL-6 and IL-1β expression and cell proliferation, respectively.

RESULTS

We found that LINC00689 and HOXA3 are overexpressed and miR-338-3p is decreased in gastric cancer cells. Compared to control specimens, LINC00689 is overexpressed in gastric cancer specimens and the level of LINC00689 was up-regulated in 32 cases (32/40; 80.0%) compared to control samples. LINC00689 increased cell growth, epithelial-mesenchymal transition (EMT) development and secretion of inflammatory factors in gastric cancer. Compared to control specimens, miR-338-3p expression was decreased in gastric cancer specimens and a Pearson's correlation assay revealed that miR-338-3p was negatively correlated with LINC00689 expression in gastric cancer specimens. HOXA3 was identified as one target gene of miR-338-3p and Ectopic expression of LINC00689 suppressed miR-338-3p and enhanced HOXA3 expression in HGC-27 cells. LINC00689 enhanced cell growth, EMT development and secretion of inflammatory factors by promoting HOXA3.

CONCLUSIONS

LINC00689 may present a potential future target for gastric cancer treatment.

Unleash multifunctional role of long noncoding RNAs biomarker panel in breast cancer: a predictor classification model

Aim: We aimed to explore the circulating expression profile of nine lncRNAs (MALAT1, HOTAIR, PVT1, H19, ROR, GAS5, ANRIL, BANCR, MIAT) in breast cancer (BC) patients relative to normal and risky individuals. Methods: Serum relative expressions of the specified long non-coding RNAs were quantified in 155 consecutive women, using quantitative reverse-transcription PCR. Random Forest (RF) and decision tree were also applied. Results: Significant MALAT1 upregulation and GAS5 downregulation could discriminate risky women from healthy controls. Overexpression of the other genes showed good diagnostic performances. Lower GAS5 levels were associated with metastasis and recurrence. RF model revealed a better performance when combining gene expression patterns with risk factors. Conclusion: The studied panel could be utilized as diagnostic/prognostic biomarkers in BC, providing promising epigenetic-based therapeutic targets.

Perspectives on the Role of Non-Coding RNAs in the Regulation of Expression and Function of the Estrogen Receptor

Estrogen receptors (ERs) comprise several nuclear and membrane-bound receptors with different tissue-specific functions. ERα and ERβ are two nuclear members of this family, whereas G protein-coupled estrogen receptor (GPER), ER-X, and Gq-coupled membrane estrogen receptor (Gq-mER) are membrane-bound G protein-coupled proteins. ERα participates in the development and function of several body organs such as the reproductive system, brain, heart and musculoskeletal systems. ERβ has a highly tissue-specific expression pattern, particularly in the female reproductive system, and exerts tumor-suppressive roles in some tissues. Recent studies have revealed functional links between both nuclear and membrane-bound ERs and non-coding RNAs. Several oncogenic lncRNAs and miRNAs have been shown to exert their effects through the modulation of the expression of ERs. Moreover, treatment with estradiol has been shown to alter the malignant behavior of cancer cells through functional axes composed of non-coding RNAs and ERs. The interaction between ERs and non-coding RNAs has functional relevance in several human pathologies associated with estrogen regulation, such as cancers, intervertebral disc degeneration, coronary heart disease and diabetes. In the current review, we summarize scientific literature on the role of miRNAs and lncRNAs on ER-associated signaling and related disorders.

A long non-coding RNA OLBC15 promotes triple-negative breast cancer progression via enhancing ZNF326 degradation

BACKGROUND

The long non-coding RNAs (lncRNAs) have been involved in various processes, including cancer. However, the function of many lncRNAs is still elusive in triple-negative breast cancer (TNBC).

METHODS

LncRNA profiling was used to screen for novel lncRNAs related to TNBC. OLBC15 expression was measured via qRT-PCR. In vitro migration and viability assays were conducted to determine the oncogenic role of OLBC15. Xenograft and metastatic models were performed to further investigate effects in vivo. RNA immunoprecipitation (RIP), mass spectrometry (MS), and fluorescence in situ hybridization (FISH) strategies were designed to identify the interaction between ZNF326 and OLBC15.

RESULTS

In the current study, we have identified a novel oncogenic lncRNA termed OLBC15 via lncRNA profiling. OLBC15 is highly expressed especially in triple-negative breast cancer. OLBC15 promoted viability and migration in breast cancer cells. Moreover, OLBC15 could accelerate metastasis and xenograft tumor growth. Mechanistic study suggested that OLBC15 could bind a well-characterized tumor suppressor ZNF326 and OLBC15-ZNF326 interaction resulted in ZNF326 destabilization. OLBC15 induced proteasomal ZNF326 degradation through enhanced ubiquitination. OLBC15 and ZNF326 protein expression is also negatively correlated in clinical specimens.

CONCLUSIONS

Collectively, OLBC15 may serve as an oncogenic lncRNA to facilitate TNBC progression and a putative target for therapeutic anti-breast cancer intervention.

Effect of LncRNA MIAT on Prognosis of Hand-assisted Laparoscopic or Laparoscopic-assisted Colectomy for Colorectal Cancer

PURPOSE

The current study aims to explore the effect of myocardial infarction associated transcript (MIAT) level on the long-term prognosis of hand-assisted laparoscopic colectomy (HALC) or laparoscopic-assisted colectomy (LAC) for colorectal cancer (CC).

MATERIALS AND METHODS

A total of 320 CC patients were included. Patients were randomized into HALC and LAC group.

RESULTS

MIAT level in CC tissue was upregulated, and had a significant positive association with its level in serum. MIAT levels in both CC tissue and serum were correlated with lymph node metastasis and histologic grading. Survival analysis showed that the overall survival rate in 3 years after operation was significantly lower in HALC-High MIAT group (P<0.05). When MIAT level is <10.9 in CC tissue or 8.7 in serum, 100% of patients who underwent HALC will be alive for >3 years.

CONCLUSIONS

For patients with low MIAT level, both HALC and LAC are available, otherwise, LAC is more recommended.

Silence of lncRNA MIAT-mediated inhibition of DLG3 promoter methylation suppresses breast cancer progression via the Hippo signaling pathway

As the foremost common female malignancy, breast cancer (BC) poses a significant public health stumbling block. Although treatment protocols have improved over the years, the overall prognosis of BC remains unsatisfactory. Extensive investigations have taken place into long non coding RNAs (lncRNAs) pertaining to their involvement in carcinogenesis. The current study in connection with bioinformatics tools aimed to identify the myocardial infarction associated transcript (MIAT) as a BC-related differentially expressed lncRNA in an attempt to elucidate the effect of MIAT in BC cells. MIAT was initially overexpressed while DLG3 was down-regulated in BC. BC cells were subsequently treated with si-MIAT or/and si-DLG3, after which the expressions of DLG3 and the Hippo signaling pathway-related proteins were evaluated to analyze their regulatory mechanism in BC, which indicated that MIAT inhibition up-regulated DLG3 and activated the Hippo signaling pathway to suppress proliferation and promote apoptosis of BC cells. MS-PCR and RIP assays demonstrated that MIAT bound to the methylation proteins DNMT1, DNMT3A and DNMT3B, promoted the methylation of CpG islands in DLG3 promoter and inhibited the DLG3 expression. Moreover, our data suggested that DLG3 could bind to MST2 and regulate LAST1, which prevented the nuclear translocation of YAP. The in vitro results were further verified via the in vivo findings. Taken together, the central findings of our study demonstrate that MIAT silencing inhibits BC progression by means of up-regulating DLG3 via activation of the Hippo signaling pathway, highlighting a novel potential therapeutic target for the treatment of the BC.

Long Non-coding RNA MIAT Mediates Non-small Cell Lung Cancer Development Through Regulating the miR-128-3p/PELI3 Axis

In this study, we set out to characterize the expression status of long non-coding RNA (lncRNA) Myocardial Infarction Associated Transcript (MIAT) in non-small cell lung cancer (NSCLC) and elucidate its mechanistic contribution to this disease. Relative expression levels of MIAT, Pellino E3 Ubiquitin Protein Ligase Family Member 3 (PELI3), and microRNA (miR)-128-3p were analyzed by real-time polymerase chain reaction. PELI3 protein level was determined by immunoblotting. Cell viability and proliferation were evaluated by the MTT assay and colony formation assay, respectively. Cell invasion and migration were assessed by wound-healing closure and transwell assays, respectively. The regulatory actions of miR-128-3p on both MIAT and PELI3 were interrogated by luciferase reporter assay. We demonstrated the aberrant upregulation of MIAT in NSCLC and its association with tumor progression. We further uncovered the negative correlation among MIAT, PELI3, and miR-128-3p. MIAT deficiency significantly compromised cell viability, proliferation, invasion, and migration, while increased miR-128-3p and decreased PELI3 expressions. Application of miR-128-3p inhibitor significantly stimulated luciferase activities driven by both MIAT and PELI3 promoter and phenotypically promoted cell viability, proliferation, migration, and invasion. Our study highlighted the mechanistic contribution of the MIAT/miR-128-3p/PELI3 signaling cascade in NSCLC.

MIAT inhibits proliferation of cervical cancer cells through regulating miR-150-5p

Background

To characterize the MIAT expression in cervical cancer and elucidate its mechanistic involvement in the tumor biology of this disease.

Methods

The relative expression of MIAT and miR-150 was determined by real-time PCR. Cell proliferation was measured by the CCK-8 and clonogenic assay. The anchorage-independent growth was evaluated by soft agar assay. The in vivo tumor progression was assayed with xenograft mice model. The regulatory effect of miR-150 on MIAT was interrogated by luciferase reporter assay. The endogenous CNKD1B protein was detected by western blotting.

Results

The low expression of MIAT was characterized in cervical cancer, which associated with relatively poor prognosis. Ectopic expression of MIAT inhibited malignant growth of cervical cancer both in vitro and in vivo. Mechanistically, MIAT regulated CDKN1B expression via competition with miR-150, and miR-150-inhibition directly suppressed cervical cancer cell growth.

Conclusions

Our study characterized the anti-tumor property of MIAT in cervical cancer and elucidated its competitively regulation of CDKN1B with miR-150. Our data highlighted the critical role of MIAT-miR-150-CDKN1B signaling axis in cervical cancer.

The role of long non-coding RNA MIAT in cancers

Long non-coding RNAs (lncRNAs), a kind of non-coding single-strand RNAs, play an important role as carcinogenic genes or tumor suppressors in the development of human cancer. Myocardial infarction-associated transcript (MIAT) was first identified as a lncRNA in 2006 and originally isolated as a candidate gene for myocardial infarction. Later, it was reported that MIAT exhibits regulatory effects on the human cell cycle. Since its discovery, MIAT has also been identified as a carcinogenic regulator in many malignant tumors. High expression of MIAT is related to the clinicopathological characteristics of cancer patients. It can also regulate cell proliferation, invasion, metastasis, and anti-apoptosis through a variety of mechanisms. Therefore, MIAT is considered a potential biomarker and therapeutic target in cancer. In this review, we summarize the biological function, mechanism, and potential clinical significance of MIAT during tumorigenesis.

Long Noncoding RNAs Control the Modulation of Immune Checkpoint Molecules in Cancer

Long noncoding RNAs (lncRNA) that are associated with immune checkpoints have not been identified, and the mechanism by which such lncRNAs might regulate the expression of immune checkpoints is unknown in human cancer. Immune checkpoint-associated lncRNAs (ICP-lncRNA) were identified and validated via a comprehensive bioinformatic analysis of The Cancer Genome Atlas data. These ICP-lncRNAs were involved in key immune response and immune cell receptor signaling pathways. The expression of ICP-lncRNAs was upregulated and correlated with a poor prognosis in patients with cancer. HLA complex P5 (HCP5) and myocardial infarction associated transcript (MIAT) promoted tumor growth and upregulated the expression of PD-L1/CD274 via a competing endogenous RNA mechanism of sponging miR-150-5p. The combination of MIAT knockdown and PD-L1 antibody administration showed a synergistic inhibitory effect on tumor growth. Finally, the expression of both HCP5 and MIAT was confirmed to be transcriptionally suppressed by CCCTC-binding factor (CTCF), and lipopolysaccharide induced CTCF eviction from the HCP5 and MIAT promoters, attenuating the transcriptionally suppressive activity of CTCF. This study enlarges the functional landscape of known lncRNAs in human cancer and indicates novel insights into their roles in the field of tumor immunity and immunotherapy. These findings may aid in the comprehensive management of human cancer with immunotherapy.

Long non-coding RNA MIAT promotes the growth of melanoma via targeting miR-150

Melanoma is a common skin cancer and it can lead to high mortality probably by early invasion and metastasis. LncRNA MIAT is involved in tumor proliferation, invasion and epithelial-to-mesenchymal transition (EMT). However, the roles of MIAT in melanoma still require further investigation. Thus, the aim of the study is to investigate the roles of MIAT in melanoma, especially the effects of MIAT on EMT of melanoma cancer cells. The results showed that the expression of MIAT was significantly upregulated in melanoma tissue and cells compared with the normal skin and normal melanocytes; moreover, miR-150 was confirmed as a target of MIAT. Furthermore, knockdown of MIAT inhibited cell proliferation and invasion in melanoma cancer cells and transfection of miR-150 inhibitors partial abrogated the anti-tumor effects of MIAT siRNA. In addition, MIAT siRNA also inhibited the EMT of melanoma cells, while miR-150 inhibitors can reverse the effects of MIAT siRNA. Finally, knockdown of MIAT also inhibited the carcinogenic effects of melanoma in vivo by targeting miR-150. In conclusion, we reported that MIAT promotes the proliferation, invasion and EMT of melanoma cells via targeting miR-150, which suggested that MIAT might be a therapeutic target for the treatment of melanoma.

Identification of serum exosomal lncRNA MIAT as a novel diagnostic and prognostic biomarker for gastric cancer

Background

Accumulating evidence has demonstrated that long non‐coding RNAs (lncRNAs) MIAT is significantly upregulated in many cancer types including gastric cancer (GC). However, the potential clinical significance of serum exosomal MIAT in GC is unknown.

Methods

In this study, a total of 109 GC patients, 48 gastric adenoma patients, and 50 healthy individuals were recruited. Serum exosomal MIAT levels were detected in all participants using quantitative real‐time reverse transcription‐polymerase chain reaction (qRT‐PCR).

Results

The exosomes we extracted from the serum samples were positive for TSG101, CD63, and Flotillin‐1, which were known exosome markers. Serum exosomal MIAT levels were significantly higher in GC patients than in gastric adenoma patients and healthy controls. Interestingly, gastric adenoma patients with higher serum exosomal MIAT expression were more prone to develop GC. In addition, serum exosomal MIAT levels were significantly decreased in post‐treatment blood samples compared to pre‐treatment samples, while markedly increased in the cases suffering recurrence. Moreover, serum exosomal MIAT upregulation was significantly associated with worse clinical variables and shorter survival. Furthermore, serum exosomal MIAT was identified as an independent prognostic factor for GC.

Conclusions

Collectively, serum exosomal lncRNA MIAT might serve as a promising novel biomarker for monitoring the progression of GC.

Application of the microRNA-302/367 cluster in cancer therapy

As a novel class of noncoding RNAs, microRNAs (miRNAs) can effectively silence their target genes at the posttranscriptional level. Various biological processes, such as cell proliferation, differentiation, and motility, are regulated by miRNAs. In different diseases and different stages of disease, miRNAs have various expression patterns, which makes them candidate prognostic markers and therapeutic targets. Abnormal miRNA expression has been detected in numerous neoplastic diseases in humans, which indicates the potential role of miRNAs in tumorigenesis. Previous studies have indicated that miRNAs are involved in nearly the entire process of tumor development. MicroRNA‐302a, miR‐302b, miR‐302c, miR‐302d, and miR‐367 are members of the miR‐302/367 cluster that plays various biological roles in diverse neoplastic diseases by targeting different genes. These miRNAs have been implicated in several unique characteristics of cancer, including the evasion of growth suppressors, the sustained activation of proliferative signaling, the evasion of cell death and senescence, and the regulation of angiogenesis, invasion, and metastasis. This review provides a critical overview of miR‐302/367 cluster dysregulation and the subsequent effects in cancer and highlights the vast potential of members of this cluster as therapeutic targets and novel biomarkers.

Piwi-interacting RNAs play a role in vitamin C-mediated effects on endothelial aging

The underlying mechanisms that mediate the effects of vitamin C on endothelial cell aging are widely unknown. To investigate whether Piwi-interacting RNAs (piRNAs) are involved in this process, an endothelial aging model was induced in vitro using H₂O₂ in human umbilical vein endothelial cells (HUVECs) and then treated with vitamin C (VC). Untreated HUVECs without H₂O₂ exposure were used to serve as the negative control group. Cell cycle, cell viability, and aging-associated protein expression were assessed, and RNA sequencing was performed to reveal the piRNA profile. Functional and regulatory networks of the different piRNA target genes were predicted by the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and Gene Ontology (GO) analysis. H₂O₂ induced G1 phase cell arrest, decreased cell viability, and upregulated the senescence marker p16 in HUVECs. We found that VC treatment inhibited G1 phase cell arrest, increased the number of cells in the S and G2/M phases, increased cell viability, and decreased p16 expression. The piRNA expression profiles revealed that a large proportion of piRNAs that were differentially expressed in H₂O₂-treated HUVECs were partly normalized by VC. Furthermore, a number of piRNAs associated with the response to VC in H₂O₂-treated HUVECs were linked with senescence and cell cycle-related pathways and networks. These results indicate that the ability of VC to attenuate H₂O₂-mediated endothelial cell senescence may be associated with changes in expression of piRNAs that are linked to the cell cycle.

Long Intergenic Non-Coding RNA 01121 Promotes Breast Cancer Cell Proliferation, Migration, and Invasion via the miR-150-5p/HMGA2 Axis

Purpose

Long intergenic noncoding RNA 01121 (LINC01121) has been reported to be aberrantly expressed and acts as an oncogene in pancreatic cancer. However, the detailed molecular mechanism of LINC01121 in breast cancer remains largely unclear. In this study, we aimed to investigate the expression and biological function of LINC01121 in breast cancer.

Methods

LINC01121 and miR-150-5p expression were measured in breast cancer cell lines using quantitative reverse transcription PCR. MTS and flow cytometry assays were performed to determine cell proliferation, the cell cycle, and apoptosis. Cell migration and invasion were assessed by transwell assay. The protein expression of HMGA2 in breast cancer cell lines was measured by Western blotting. A luciferase reporter assay was used to assess the binding of LINC01121 and miR-150-5p.

Results

We found that LINC01121 was markedly up-regulated in breast cancer cell lines compared with normal breast epithelial cells. LINC01121 down-regulation markedly suppressed cell proliferation, cell cycle progression, migration, and invasion and promoted apoptosis in breast cancer cells. Further investigation showed that LINC01121 could serve as a molecular sponge for miR-150-5p and indirectly modulate the expression of its target, HMGA2. Moreover, miR-150-5p knockdown rescued the effects of LINC01121 down-regulation on HMGA2 protein expression, cell proliferation, cell cycle progression, apoptosis, migration, and invasion in breast cancer cells.

Conclusion

Knockdown LINC01121 inhibited breast cancer cell proliferation, migration, and invasion via the miR-150-5p/HMGA2 axis.

Silence of lncRNA MIAT protects ATDC5 cells against lipopolysaccharides challenge via up-regulating miR-132

The over-expanding role of lncRNA myocardial infarction associated transcript (MIAT) in various human diseases has been recently revealed. This study attempted to see the role of MIAT in a cell model of osteoarthritis (OA). ATDC5 cells were subjected to lipopolysaccharides (LPS) to mimic a cell model of OA. The effects of MIAT on the model were tested by performing CCK-8 assay, flow cytometry, qRT-PCR, western blot and ELISA. The downstream miRNA and signalling pathways were studied by utilizing qRT-PCR and western blot. Transfection of ATDC5 cells with the shRNA specific against MIAT significantly attenuated LPS-evoked apoptosis and cytokines release. At the meantime, the viability loss and the cleavage of caspases were ameliorated as well. MIAT overexpressed lead to the opposite result. Further, miR-132 was found to be negatively regulated by MIAT. The protective effects of MIAT silence were flattened when miR-132 expression was suppressed. Besides that the inhibitory effects of MIAT silence on LPS-evoked NF-κB and JNK activation were eliminated by miR-132 silence. This study illustrated that silence of MIAT protected ATDC5 cells against LPS challenge. The chondroprotective effects of MIAT silence may be via up-regulation of miR-132 and inhibition of NF-κB and JNK pathways.

Long noncoding RNAs and exosomal lncRNAs: classification, and mechanisms in breast cancer metastasis and drug resistance

Breast cancer is the most common cancer, and the second cause of cancer-related deaths (after lung cancer) among women. Developing tumor metastasis and invasion is the most important cause of death in breast cancer patients. Several key factors participate in breast cancer metastasis including long noncoding RNAs (lncRNAs). lncRNAs are a category of cellular RNAs that are longer than 200 nucleotides in length. Accumulating evidence suggests that lncRNAs have the potential to be promising diagnostic, prognostic biomarkers and therapeutic targets in breast cancer. Understanding the role of lncRNAs and their mechanisms of functions might help to further discovery of breast cancer biological characteristics. In this review, we discuss physiological functions, epigenetic regulation, transcriptional regulation of lncRNAs, and their important role in tumor progression and metastasis. Some lncRNAs function as oncogenes and some function as tumor suppressors. Interestingly, recent reports depict that hypomethylation of promoters of lncRNAs play a pivotal role in cancer progression, suggesting the importance of epigenetic regulation. Furthermore, we discuss the role of lncRNAs in exosomes and their function in drug resistance, and therapeutic importance of exosomal lncRNAs in cancer biology. In summary, lncRNAs have a great potential to consider them as novel prognostic biomarkers as well as new therapeutic targets in breast cancer.

LncRNAs Regulatory Networks in Cellular Senescence

Long noncoding RNAs (lncRNAs) are a class of transcripts longer than 200 nucleotides with no open reading frame. They play a key role in the regulation of cellular processes such as genome integrity, chromatin organization, gene expression, translation regulation, and signal transduction. Recent studies indicated that lncRNAs are not only dysregulated in different types of diseases but also function as direct effectors or mediators for many pathological symptoms. This review focuses on the current findings of the lncRNAs and their dysregulated signaling pathways in senescence. Different functional mechanisms of lncRNAs and their downstream signaling pathways are integrated to provide a bird’s-eye view of lncRNA networks in senescence. This review not only highlights the role of lncRNAs in cell fate decision but also discusses how several feedback loops are interconnected to execute persistent senescence response. Finally, the significance of lncRNAs in senescence-associated diseases and their therapeutic and diagnostic potentials are highlighted.

Evaluation of Carum-loaded Niosomes on Breast Cancer Cells:Physicochemical Properties, In Vitro Cytotoxicity, Flow Cytometric, DNA Fragmentation and Cell Migration Assay

Thymoquinone (TQ), a phytochemical compound found in Carum carvil seeds (C. carvil), has a lot of applications in medical especially cancer therapy. However, TQ has a hydrophobic nature, and because of that, its solubility, permeability and its bioavailability in biological mediums are poor. To diminish these drawbacks, we have designed a herbal carrier composed of Ergosterol (herbal lipid), Carum carvil extract (Carum) and nonionic surfactants for herbal cancer treatment. C. carvil was extracted and characterized by GC/Mass. Two different formulations containing TQ and Carum were encapsulated into niosomes (Nio/TQ and Nio/Carum, respectively) and their properties were compared together. Morphology, size, zeta potential, encapsulation efficiency (EE%), profile release rate, in vitro cytotoxicity, flow cytometric, DNA fragmentation and cell migration assay of formulations were evaluated. Results show that both loaded formulations have a spherical morphology, nanometric size and negative zeta potential. EE% of TQ and Carum loaded niosomes was about 92.32% ± 2.32 and 86.25% ± 1.85, respectively. Both loaded formulations provided a controlled release compared with free TQ. MTT assay showed that loaded niosomes have more anti-cancer activity compared with Free TQ and free Carum against MCF-7 cancer cell line and these results were confirmed by flow cytometric analysis. Cell cycle analysis showed G2/M arrest in TQ, Nio/TQ and Nio/Carum formulations. TQ, Nio/TQ and Nio/Carum decreased the migration of MCF7 cells remarkedly. These results show that the TQ and Carum loaded niosomes are novel carriers with high efficiency for encapsulation of low soluble phytochemicals and also would be favourable systems for breast cancer treatment.

Long non-coding RNA ES1 controls the proliferation of breast cancer cells by regulating the Oct4/Sox2/miR-302 axis

ES1 is a long non-coding RNA (lncRNA) that regulates pluripotency of human embryonic stem cells, which is known to be a downstream target of stemness factors Oct4 and Nanog, and serves as a modular scaffold for Sox2. However, the role of ES1 in cancer biology is not fully characterized. The results of our study show that ES1 transcript is upregulated in both high-grade and P53-mutated breast tumor tissues. Knockdown experiments show that ES1 suppression in breast cancer cells restricts cancer cell proliferation and cell cycle progression. Moreover, ES1 inhibition can also induce apoptosis and cellular senescence. Additionally, our data reveal that ES1 transcript promotes cell migration as well as the epithelial to mesenchymal transition of breast cancer cells. Furthermore, loss of ES1 expression downregulates the expression of Oct4/Sox2 and consequently leads to downregulation of their targets, miR-302 and miR-106b. Altogether, for the first time, our findings reveal that ES1 controls the proliferation and death of breast cancer cells by regulating the Oct4/Sox2/miR-302/miR-106b axis.

SNHG6 is upregulated in primary breast cancers and promotes cell cycle progression in breast cancer-derived cell lines

BACKGROUND

Long non-coding RNAs (lncRNAs) are known as RNAs that do not encode proteins and that are more than 200 nucleotides in size. Previously, it has been found that LncRNAs play crucial roles in normal cellular processes, including proliferation and apoptosis. A growing body of evidence suggests that lncRNAs may also play regulatory roles in the initiation, progression and metastasis of various malignancies, including breast cancer. SNHG6 is a lncRNA that has previously been found to contribute to the initiation and progression of hepatocellular and gastric carcinomas. In this study, the clinical significance of SNHG6 expression in breast cancer was investigated.

METHODS

SNHG6 expression in primary breast cancer tissues was assessed using RT-qPCR. The functional role of SNHG6 was investigated using RNAi-mediated silencing and exogenous overexpression in breast cancer-derived cells. MTT, colony formation, cell cycle, apoptosis and senescence assays were used to determine the impact of SNHG6 expression on breast cancer-derived cells. The effect of SNHG6 on the migration and epithelial-to-mesenchymal transition (EMT) of breast cancer-derived cells was determined using scratch wound healing and immunofluorescence assays, respectively.

RESULTS

We found that the expression of SNHG6 was significantly upregulated in primary high-grade and progesterone receptor (PR)-positive breast tumours. Additional siRNA-based experiments revealed that SNHG6 silencing led to G1 cell cycle arrest in SK-BR-3 and MDA-MB-231 breast cancer-derived cells. Moreover, we found that SNHG6 silencing led to suppressed breast cancer cell proliferation by inducing apoptosis and senescence. Our data also indicate that SNHG6 may contribute to the migration and EMT of breast cancer cells.

CONCLUSIONS

Our results indicate that lncRNA SNHG6 is involved in breast cancer development and may be considered as a potential biomarker for the diagnosis, prognosis and treatment of breast cancer.

RNA sequencing reveals a key role for the long non-coding RNA MIAT in regulating neuroblastoma and glioblastoma cell fate

Myocardial Infarction Associated Transcript (MIAT) is a subnuclear lncRNA that interferes with alternative splicing and is associated with increased risk of various heart conditions and nervous system tumours. The current study aims to elucidate the role of MIAT in cell survival, apoptosis and migration in neuroblastoma and glioblastoma multiforme. To this end, MIAT was silenced by MIAT-specific siRNAs in neuroblastoma and glioblastoma cell lines, and RNA sequencing together with a series of functional assays were performed. The RNA sequencing has revealed that the expression of an outstanding number of genes is altered, including genes involved in cancer-related processes, such as cell growth and survival, apoptosis, reactive oxygen species (ROS) production and migration. Furthermore, the functional studies have confirmed the RNA sequencing leads, with our key findings suggesting that MIAT knockdown eliminates long-term survival and migration and increases basal apoptosis in neuroblastoma and glioblastoma cell lines. Taken together with the recent demonstration of the involvement of MIAT in glioblastoma, our observations suggest that MIAT could possess tumour-promoting properties, thereby acting as an oncogene, and has the potential to be used as a reliable biomarker for neuroblastoma and glioblastoma and be employed for prognostic, predictive and, potentially, therapeutic purposes for these cancers.

LncRNA-ANRIL inhibits cell senescence of vascular smooth muscle cells by regulating miR-181a/Sirt1

BACKGROUND

Cardiovascular disease is one of the major threats to human life and health, and vascular aging is an important cause of its occurrence. Antisense non-coding RNA in the INK4 locus (ANRIL) is a kind of long non-coding RNA (lncRNA) that plays important roles in cell senescence. However, the role and mechanism of ANRIL in senescence of vascular smooth muscle cells (VSMCs) are unclear.

METHODS

Cell viability and cell cycle were evaluated using an MTT assay and flow cytometry analysis, respectively. Senescence-associated (SA)-β-galactosidase (gal) staining was used to determine cell senescence. Dual luciferase reporter assays were conducted to confirm the binding of ANRIL and miR-181a, as well as miR-181a and Sirt1. The expression of ANRIL, miR-181a, and Sirt1 was determined using qRT-PCR and protein levels of SA-β-gal and p53-p21 pathway-related proteins were evaluated by Western blotting.

RESULTS

ANRIL and Sirt1 were down-regulated, whereas miR-181a was up-regulated in aging VSMCs. In young and aging VSMCs, over-expression of ANRIL could down-regulate miR-181a and up-regulate Sirt1. MTT and SA-β-gal staining assays showed that over-expression of ANRIL and inhibition of miR-181a promoted cell viability and inhibited VSMC senescence. The dual-luciferase reporter assay determined that miR-181a directly targets ANRIL and the 3'-UTR of Sirt1. Furthermore, over-expression of ANRIL inhibited cell cycle arrest and the p53-p21 pathway.

CONCLUSION

ANRIL promotes cell viability and inhibits senescence in VSMCs, possibly by regulating miR-181a/Sirt1, and alleviating cell cycle arrest by inhibiting the p53-p21 pathway. This study provides novel insights for the role of ANRIL in the development of cell senescence.

Long non-coding RNAs differential expression in breast cancer subtypes: What do we know?

Breast Cancer (BC) is the most commonly diagnosed cancer and is the leading cause of cancer deaths in women. BC is a heterogeneous disease with different clinical and genetic features. According to immunohistochemical markers, BC is subdivided into four main subtypes: luminal A, luminal B, ERBB2 positive and triple negative. Long non-coding RNAs (lncRNAs) are transcripts with more than 200 nucleotides and deregulated lncRNAs are associated with human diseases, including BC. In order to improve BC molecular classification, non-coding RNAs (ncRNAs), including lncRNAs, have been used. In this review, we focus on lncRNAs with differential expression in BC subtypes and how these RNAs may act to contribute to BC heterogeneity. We also emphasize the potential of these lncRNAs as biomarkers.

Non-Coding RNAs in Breast Cancer: Intracellular and Intercellular Communication

Non-coding RNAs (ncRNAs) are regulators of intracellular and intercellular signaling in breast cancer. ncRNAs modulate intracellular signaling to control diverse cellular processes, including levels and activity of estrogen receptor α (ERα), proliferation, invasion, migration, apoptosis, and stemness. In addition, ncRNAs can be packaged into exosomes to provide intercellular communication by the transmission of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) to cells locally or systemically. This review provides an overview of the biogenesis and roles of ncRNAs: small nucleolar RNA (snRNA), circular RNAs (circRNAs), PIWI-interacting RNAs (piRNAs), miRNAs, and lncRNAs in breast cancer. Since more is known about the miRNAs and lncRNAs that are expressed in breast tumors, their established targets as oncogenic drivers and tumor suppressors will be reviewed. The focus is on miRNAs and lncRNAs identified in breast tumors, since a number of ncRNAs identified in breast cancer cells are not dysregulated in breast tumors. The identity and putative function of selected lncRNAs increased: nuclear paraspeckle assembly transcript 1 (NEAT1), metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), steroid receptor RNA activator 1 (SRA1), colon cancer associated transcript 2 (CCAT2), colorectal neoplasia differentially expressed (CRNDE), myocardial infarction associated transcript (MIAT), and long intergenic non-protein coding RNA, Regulator of Reprogramming (LINC-ROR); and decreased levels of maternally-expressed 3 (MEG3) in breast tumors have been observed as well. miRNAs and lncRNAs are considered targets of therapeutic intervention in breast cancer, but further work is needed to bring the promise of regulating their activities to clinical use.