Long non-coding RNA LINC00504 regulates the Warburg effect in ovarian cancer through inhibition of miR-1244

LncRNAs exhibit subtype-specific expression, survival associations, and cancer-promoting effects in breast cancer

Long non-coding RNAs (lncRNAs) play important roles in cancer progression, influencing processes such as invasion, metastasis, and drug resistance. Their reported cell type-dependent expression patterns suggest the potential for specialized functions in specific contexts. In breast cancer, lncRNA expression has been associated with different subtypes, highlighting their relevance in disease heterogeneity. However, our understanding of lncRNA function within breast cancer subtypes remains limited, warranting further investigation. We conducted a comprehensive analysis using the TANRIC dataset derived from the TCGA-BRCA cohort, profiling the expression, patient survival associations and immune cell type correlations of 12,727 lncRNAs across subtypes. Our findings revealed subtype-specific associations of lncRNAs with patient survival, tumor infiltrating lymphocytes and other immune cells. Targeting of lncRNAs exhibiting subtype-specific survival associations and expression in a panel of breast cancer cells demonstrated a selective reduction in cell proliferation within their associated subtype, supporting subtype-specific functions of certain lncRNAs. Characterization of HER2 + -specific lncRNA LINC01269 and TNBC-specific lncRNA AL078604.2 showed nuclear localization and altered expression of hundreds of genes enriched in cancer-promoting processes, including apoptosis, cell proliferation and immune cell regulation. This work emphasizes the importance of considering the heterogeneity of breast cancer subtypes and the need for subtype-specific analyses to fully uncover the relevance and potential impact of lncRNAs. Collectively, these findings demonstrate the contribution of lncRNAs to the distinct molecular, prognostic, and cellular composition of breast cancer subtypes.

CircRNA-regulated glucose metabolism in ovarian cancer: an emerging landscape for therapeutic intervention

Ovarian cancer (OC) has the highest mortality rate among female reproductive system tumours, with limited efficacy of traditional treatments and 5-year survival rates that rarely exceed 40%. Circular RNA (circRNA) is a stable endogenous circular RNA that typically regulates protein expression by binding to downstream miRNA. It has been demonstrated that circRNAs play an important role in the proliferation, migration, and glucose metabolism (such as the Warburg effect) of OC and can regulate the expression of glucose metabolism-related proteins such as GLUT1 and HK2, promoting anaerobic glycolysis of cancer cells, increasing glucose uptake and ATP production, and affecting energy supply and biosynthetic substances to support tumour growth and invasion. This review summarises the formation and characteristics of circRNAs and focuses on their role in regulating glucose metabolism in OC cells and their potential therapeutic value, providing insights for identifying new therapeutic targets.

Mesenchymal Stem Cells from Familial Alzheimer's Patients Express MicroRNA Differently

Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the predominant form of dementia globally. No reliable diagnostic, predictive techniques, or curative interventions are available. MicroRNAs (miRNAs) are vital to controlling gene expression, making them valuable biomarkers for diagnosis and prognosis. This study examines the transcriptome of olfactory ecto-mesenchymal stem cells (MSCs) derived from individuals with the PSEN1(A431E) mutation (Jalisco mutation). The aim is to determine whether this mutation affects the transcriptome and expression profile of miRNAs and their target genes at different stages of asymptomatic, presymptomatic, and symptomatic conditions. Expression microarrays compare the MSCs from mutation carriers with those from healthy donors. The results indicate a distinct variation in the expression of miRNAs and mRNAs among different symptomatologic groups and between individuals with the mutation. Using bioinformatics tools allows us to identify target genes for miRNAs, which in turn affect various biological processes and pathways. These include the cell cycle, senescence, transcription, and pathways involved in regulating the pluripotency of stem cells. These processes are closely linked to inter- and intracellular communication, vital for cellular functioning. These findings can enhance our comprehension and monitoring of the disease's physiological processes, identify new disorder indicators, and develop innovative treatments and diagnostic tools for preventing or treating AD.

Research progress on the mechanism of glycolysis in ovarian cancer

Glycolysis is the preferred energy metabolism pathway in cancer cells even when the oxygen content is sufficient. Through glycolysis, cancer cells convert glucose into pyruvic acid and then lactate to rapidly produce energy and promote cancer progression. Changes in glycolysis activity play a crucial role in the biosynthesis and energy requirements of cancer cells needed to maintain growth and metastasis. This review focuses on ovarian cancer and the significance of key rate-limiting enzymes (hexokinase, phosphofructokinase, and pyruvate kinase, related signaling pathways (PI3K-AKT, Wnt, MAPK, AMPK), transcription regulators (HIF-1a), and non-coding RNA in the glycolytic pathway. Understanding the relationship between glycolysis and these different mechanisms may provide new opportunities for the future treatment of ovarian cancer.

Comprehensive analyses of fatty acid metabolism-related lncRNA for ovarian cancer patients

Ovarian cancer (OC) is a disease with difficult early diagnosis and treatment and poor prognosis. OC data profiles were downloaded from The Cancer Genome Atlas. Eight key fatty acid metabolism-related long non-coding RNAs (lncRNAs) were finally screened for building a risk scoring model by univariate/ multifactor and least absolute shrinkage and selection operator (LASSO) Cox regression. To make this risk scoring model more applicable to clinical work, we established a nomogram containing the clinical characteristics of OC patients after confirming that the model has good reliability and validity and the ability to distinguish patient prognosis. To further explore how these key lncRNAs are involved in OC progression, we explored their relationship with LUAD immune signatures and tumor drug resistance. The structure shows that the risk scoring model established based on these 8 fatty acid metabolism-related lncRNAs has good reliability and validity and can better predict the prognosis of patients with different risks of OC, and LINC00861in these key RNAs may be a hub gene that affects the progression of OC and closely related to the sensitivity of current OC chemotherapy drugs. In addition, combined with immune signature analysis, we found that patients in the high-risk group are in a state of immunosuppression, and Tfh cells may play an important role in it. We innovatively established a prognostic prediction model with excellent reliability and validity from the perspective of OC fatty acid metabolism reprogramming and lncRNA regulation and found new molecular/cellular targets for future OC treatment.

Long noncoding RNAs, glucose metabolism and cancer (Review)

Cancer is a serious and potentially life-threatening disease, which, despite numerous advances over several decades, remains a challenge to treat that challenging to detect at an early stage or treat during the later stages. Long noncoding RNAs are >200 nucleotides long and do not possess protein-coding capacity, instead regulating cellular processes, such as proliferation, differentiation, maturation, apoptosis, metastasis, and sugar metabolism. Several studies have shown the role of lncRNAs and glucose metabolism in regulating several key glycolytic enzymes and the activity of multiple functional signaling pathways during tumor progression. Thus, it is possible to further learn about the effects of lncRNA and glycolytic metabolism on tumor diagnosis, treatment, and prognosis through a thorough investigation of the lncRNA expression profiles and glycolytic metabolism in tumors. This may provide a novel strategy for improving the management of several types of cancer.

Long noncoding RNAs: glycolysis regulators in gynaecologic cancers

The three most common gynaecologic cancers that seriously threaten female lives and health are ovarian cancer, cervical cancer, and endometrial cancer. Glycolysis plays a vital role in gynaecologic cancers. Several long noncoding RNAs (lncRNAs) are known to function as oncogenic molecules. LncRNAs impact downstream target genes by acting as ceRNAs, guides, scaffolds, decoys, or signalling molecules. However, the role of glycolysis-related lncRNAs in regulating gynaecologic cancers remains poorly understood. In this review, we emphasize the functional roles of many lncRNAs that have been found to promote glycolysis in gynaecologic cancers and discuss reasonable strategies for future research.

Insights on the potential oncogenic impact of long non-coding RNA nicotinamide nucleotide transhydrogenase antisense RNA 1 in different cancer types; integrating pathway(s) and clinical outcome(s) association

Long non-coding RNAs (lncRNAs) are becoming more prevalent in the cancer field arena, with functional roles in both oncogenic and onco-suppressive pathways. Despite their widespread aberrant expression in a range of human malignancies, the biological activities of the ncRNAs majority are unknown. All showed the involvement of the lncRNA nicotinamide nucleotide transhydrogenase antisense RNA 1 (NNT-AS1). Since NNT-AS1 influences cellular proliferation, invasion, migration, apoptosis, and metastasis, this lncRNA appears to be linked to deregulating the normal cellular processes driving malignancy. This was observed in breast cancer (BC), gastric cancer (GC), colorectal cancer (CRC), epithelial ovarian cancer (EOC), and hepatocellular carcinoma (HCC). The current narrative non-systematic review will discuss "the significance of lncRNAs in cancer", as well as "lncRNAs future potential application(s) as diagnostic or predictive biomarkers", therefore, comprising an opportunity as treatment target(s). The review will have a special emphasis on lncRNA NNT-AS1.

Noncoding RNAs in the Glycolysis of Ovarian Cancer

Energy metabolism reprogramming is the characteristic feature of tumors. The tumorigenesis, metastasis, and drug resistance of ovarian cancer (OC) is dependent on energy metabolism. Even under adequate oxygen conditions, OC cells tend to convert glucose to lactate, and glycolysis can rapidly produce ATP to meet their metabolic energy needs. Non-coding RNAs (ncRNAs) interact directly with DNA, RNA, and proteins to function as an essential regulatory in gene expression and tumor pathology. Studies have shown that ncRNAs regulate the process of glycolysis by interacting with the predominant glycolysis enzyme and cellular signaling pathway, participating in tumorigenesis and progression. This review summarizes the mechanism of ncRNAs regulation in glycolysis in OC and investigates potential therapeutic targets.

Piperlongumine, a piper alkaloid, enhances the efficacy of doxorubicin in breast cancer: involvement of glucose import, ROS, NF-κB and lncRNAs

Piperlongumine (PL, piplartine) is an alkaloid derived from the Piper longum L. (long pepper) roots. Originally discovered in 1961, the biological activities of this molecule against some cancer types was reported during the last decade. Whether PL can synergize with doxorubicin and the underlying mechanism in breast cancer remains elusive. Herein, we report the activities of PL in numerous breast cancer cell lines. PL reduced the migration and colony formation by cancer cells. An enhancement in the sub-G1 population, reduction in the mitochondrial membrane potential, chromatin condensation, DNA laddering and suppression in the cell survival proteins was observed by the alkaloid. Further, PL induced ROS generation in breast cancer cells. While TNF-α induced p65 nuclear translocation, PL suppressed the translocation in cancer cells. The expression of lncRNAs such as MEG3, GAS5 and H19 were also modulated by the alkaloid. The molecular docking studies revealed that PL can interact with both p65 and p50 subunits. PL reduced the glucose import and altered the pH of the medium towards the alkaline side. PL also suppressed the expression of glucose and lactate transporter in breast cancer cells. In tumor bearing mouse model, PL was found to synergize with doxorubicin and reduced the size, volume and weight of the tumor. Overall, the effects of doxorubicin in cancer cells are enhanced by PL. The modulation of glucose import, NF-κB activation and lncRNAs expression may have contributory role for the activities of PL in breast cancer.

STAT1 mediated long non-coding RNA LINC00504 influences radio-sensitivity of breast cancer via binding to TAF15 and stabilizing CPEB2 expression

Radiotherapy plays important roles in the treatment of breast cancer (BC), which develops from malignant cells in the breast. Long non-coding RNAs (lncRNAs) have been reported to be implicated in radio-resistance or radio-sensitivity of human cancer, which includes breast cancer. Nevertheless, long intergenic non-protein coding RNA 0504 (LINC00504) has not been investigated in BC. In our study, from RT-qPCR analysis, LINC00504 was found to be up-regulated in BC cells. By conducting in vitro assays, it was confirmed that the knockdown of LINC00504 could enhance the radio-sensitivity of BC cells. The regulatory mechanism of LINC00504 in BC was also verified by chromatin immunoprecipitation (ChIP), RNA immunoprecipitation (RIP) and luciferase reporter assays. From the experimental results, we knew that the up-regulation of LINC00504 was mediated by signal transducer and activator of transcription 1 (STAT1). Moreover, LINC00504 stabilized the expression of cytoplasmic polyadenylation element-binding protein 2 (CPEB2) via binding to TATA-box binding protein associated factor 15 (TAF15). Furthermore, rescue assays validated that LINC00504 participated in regulating the radio-sensitivity of BC cells via up-regulating CPEB2. In summary, our study disclosed that STAT1 could mediate LINC00504 and weaken the radio-sensitivity of BC cells via binding to TAF15 and stabilizing CPEB2 expression.

(In)Distinctive Role of Long Non-Coding RNAs in Common and Rare Ovarian Cancers

Rare ovarian cancers (ROCs) are OCs with an annual incidence of fewer than 6 cases per 100,000 women. They affect women of all ages, but due to their low incidence and the potential clinical inexperience in management, there can be a delay in diagnosis, leading to a poor prognosis. The underlying causes for these tumors are varied, but generally, the tumors arise due to alterations in gene/protein expression in cellular processes that regulate normal proliferation and its checkpoints. Dysregulation of the cellular processes that lead to cancer includes gene mutations, epimutations, non-coding RNA (ncRNA) regulation, posttranscriptional and posttranslational modifications. Long non-coding RNA (lncRNA) are defined as transcribed RNA molecules, more than 200 nucleotides in length which are not translated into proteins. They regulate gene expression through several mechanisms and therefore add another level of complexity to the regulatory mechanisms affecting tumor development. Since few studies have been performed on ROCs, in this review we summarize the mechanisms of action of lncRNA in OC, with an emphasis on ROCs.

Long non-coding RNAs: A view to kill ovarian cancer

An emerging role of long non-coding RNAs (lncRNAs) in tumor progression has been revealed in the last decade. Through interactions with nucleic acids and proteins, lncRNAs could act as enhancers, scaffolds or decoys for a number of oncoproteins and tumor suppressors. The aberrant lncRNA expression or mutations are often associated with changes in a variety of cellular processes, including proliferation, stress response and cell death. Here, we will focus on the tumor-associated lncRNAs in ovarian cancer according to their contribution to cancer hallmarks, such as intense proliferation, cell death resistance, altered energy metabolism, invasion and metastasis, and immune evasion. Moreover, the potential clinical implications of lncRNAs and their significance for the diagnosis, prognosis and therapy of ovarian cancer will be discussed.

Deciphering the Long Non-Coding RNAs and MicroRNAs Coregulation Networks in Ovarian Cancer Development: An Overview

Non-coding RNAs are emergent elements from the genome, which do not encode for proteins but have relevant cellular functions impacting almost all the physiological processes occurring in eukaryotic cells. In particular, microRNAs and long non-coding RNAs (lncRNAs) are a new class of small RNAs transcribed from the genome, which modulate the expression of specific genes at transcriptional and posttranscriptional levels, thus adding a new regulatory layer in the flux of genetic information. In cancer cells, the miRNAs and lncRNAs interactions with its target genes and functional pathways are deregulated as a consequence of epigenetic and genetic alterations occurring during tumorigenesis. In this review, we summarize the actual knowledge on the interplay of lncRNAs with its cognate miRNAs and mRNAs pairs, which interact in coregulatory networks with a particular emphasis on the mechanisms underlying its oncogenic behavior in ovarian cancer. Specifically, we reviewed here the evidences unraveling the relevant roles of lncRNAs/miRNAs pairs in altered regulation of cell migration, angiogenesis, therapy resistance, and Warburg effect. Finally, we also discussed its potential clinical implications in ovarian cancer and related endocrine disease therapies.

Circular RNA UBAP2 promotes the proliferation of prostate cancer cells via the miR-1244/MAP3K2 axis

Prostate cancer (PCa) is a common male malignant disease with a high incidence, which can seriously affect the quality of life of patients. The survival rate of patients with PCa has improved to 98.6%; however, new insights for the molecular mechanism are still urgently required. Circular RNA (circ)UBAP2 is a tumor-associated circRNA that has been demonstrated to promote the progression of various types of cancer. CircUBAP2 has been demonstrated to be significantly upregulated in PCa, but its role in the progression of PCa remains unclear. The present study aimed to provide an improved understanding of the regulatory mechanism of circUBAP2 in PCa. circUBAP2 expression was identified to be upregulated in four PCa cell lines and clinical tissues by using reverse transcription-quantitative PCR analysis. Binding sites analysis and luciferase reporter gene assay indicated that the microRNA(miR)-1244/MAP3K2 axis was the target of circUBAP2. Gain-of-function assays revealed that circUBAP2 promoted the proliferation of PCa cells by sponging miR-1244 and promoting the MAP3K2 axis. The present findings may be essential for providing new strategies in the diagnosis and targeted therapy of PCa.

Non-Coding RNAs as Biomarkers of Tumor Progression and Metastatic Spread in Epithelial Ovarian Cancer

Simple Summary

Despite advances in cancer research in recent years, efficient predictive biomarkers of tumor progression and metastatic spread for ovarian cancer are still missing. Therefore, we critically address recent findings in the field of non-coding RNAs (microRNAs and long non-coding RNAs) and DNA methylation in ovarian cancer patients as promising novel biomarkers of ovarian cancer progression.

Abstract

Ovarian cancer is one of the most common causes of death among gynecological malignancies. Molecular changes occurring in the primary tumor lead to metastatic spread into the peritoneum and the formation of distant metastases. Identification of these changes helps to reveal the nature of metastases development and decipher early biomarkers of prognosis and disease progression. Comparing differences in gene expression profiles between primary tumors and metastases, together with disclosing their epigenetic regulation, provides interesting associations with progression and metastasizing. Regulatory elements from the non-coding RNA families such as microRNAs and long non-coding RNAs seem to participate in these processes and represent potential molecular biomarkers of patient prognosis. Progress in therapy individualization and its proper targeting also rely upon a better understanding of interactions among the above-listed factors. This review aims to summarize currently available findings of microRNAs and long non-coding RNAs linked with tumor progression and metastatic process in ovarian cancer. These biomolecules provide promising tools for monitoring the patient’s response to treatment, and further they serve as potential therapeutic targets of this deadly disease.

Pyruvate kinase M2 (PKM2) in cancer and cancer therapeutics

Pyruvate kinase M2 (PKM2), a key rate-limiting enzyme of glycolysis, is a critical regulator in tumor metabolism. PKM2 has been demonstrated to overexpressed in various cancers and promoted proliferation and metastasis of tumor cells. The errant expression of PKM2 has inspired people to investigate the function of PKM2 and the therapeutic potential in cancer. In addition, some studies have shown that the upregulation of PKM2 in tumor tissues is associated with the altered expression of lncRNAs and the poor survival. Therefore, researchers have begun to unravel the specific molecular mechanisms of lncRNA-mediated PKM2 expression in cancer metabolism. As the tumor microenvironment (TME) is essential in tumor development, it is necessary to identify the role of PKM2 in TME. In this review, we will introduce the role of PKM2 in different cancers as well as TME, and summarize the molecular mechanism of PKM2-related lncRNAs in cancer metabolism. We expect that this work will lead to a better understanding of the molecular mechanisms of PKM2 that may help in developing therapeutic strategies in clinic for researchers.

miRNAs and lncRNAs as Novel Therapeutic Targets to Improve Cancer Immunotherapy

Simple Summary

Cancer onset and progression are promoted by high deregulation of the immune system. Recently, major advances in molecular and clinical cancer immunology have been achieved, offering new agents for the treatment of common tumors, often with astonishing benefits in terms of prolonged survival and even cure. Unfortunately, most tumors are still resistant to current immune therapy approaches, and basic knowledge of the resistance mechanisms is eagerly awaited. We focused our attention on noncoding RNAs, a class of RNA that regulates many biological processes by targeting selectively crucial molecular pathways and that, recently, had their role in cancer cell immune escape and modulation of the tumor microenvironment identified, suggesting their function as promising immunotherapeutic targets. In this scenario, we point out that noncoding RNAs are progressively emerging as immunoregulators, and we depict the current information on the complex network involving the immune system and noncoding RNAs and the promising therapeutic options under investigation. Novel opportunities are emerging from noncoding-RNAs for the treatment of immune-refractory tumors.

Abstract

Immunotherapy is presently one of the most promising areas of investigation and development for the treatment of cancer. While immune checkpoint-blocking monoclonal antibodies and chimeric antigen receptor (CAR) T-cell-based therapy have recently provided in some cases valuable therapeutic options, the goal of cure has not yet been achieved for most malignancies and more efforts are urgently needed. Noncoding RNAs (ncRNA), including microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), regulate several biological processes via selective targeting of crucial molecular signaling pathways. Recently, the key roles of miRNA and lncRNAs as regulators of the immune-response in cancer have progressively emerged, since they may act (i) by shaping the intrinsic tumor cell and microenvironment (TME) properties; (ii) by regulating angiogenesis, immune-escape, epithelial-to-mesenchymal transition, invasion, and drug resistance; and (iii) by acting as potential biomarkers for prognostic assessment and prediction of response to immunotherapy. In this review, we provide an overview on the role of ncRNAs in modulating the immune response and the TME. We discuss the potential use of ncRNAs as potential biomarkers or as targets for development or clinical translation of new therapeutics. Finally, we discuss the potential combinatory approaches based on ncRNA targeting agents and tumor immune-checkpoint inhibitor antibodies or CAR-T for the experimental treatment of human cancer.

Long non-coding RNA-based glycolysis-targeted cancer therapy: feasibility, progression and limitations

Metabolism reprogramming is one of the hallmarks of cancer cells, especially glucose metabolism, to promote their proliferation, metastasis and drug resistance. Cancer cells tend to depend on glycolysis for glucose utilization rather than oxidative phosphorylation, which is called the Warburg effect. Genome instability of oncogenes and tumor-inhibiting factors is the culprits for this anomalous glycolytic fueling, which results in dysregulating metabolism-related enzymes and metabolic signaling pathways. It has been extensively demonstrated that protein-coding genes are involved in this process; therefore, glycolysis-targeted therapy has been widely used in anti-tumor combined therapy via small molecular inhibitors of key enzymes and regulatory molecular. The long non-coding RNA, which is a large class of regulatory RNA with longer than 200 nucleotides, is the novel and significant regulator of various biological processes, including metabolic reprogramming. RNA interference and synthetic antisense oligonucleotide for RNA reduction have developed rapidly these years, which presents potent anti-tumor effects both in vitro and in vivo. However, lncRNA-based glycolysis-targeted cancer therapy, as the highly specific and less toxic approach, is still under the preclinical phase. In this review, we highlight the role of lncRNA in glucose metabolism and dissect the feasibility and limitations of this clinical development, which may provide potential targets for cancer therapy.

Novel lncRNAs Co-Expression Networks Identifies LINC00504 with Oncogenic Role in Luminal A Breast Cancer Cells

Long non-coding RNAs (lncRNAs) are functional transcripts with more than 200 nucleotides. These molecules exhibit great regulatory capacity and may act at different levels of gene expression regulation. Despite this regulatory versatility, the biology of these molecules is still poorly understood. Computational approaches are being increasingly used to elucidate biological mechanisms in which these lncRNAs may be involved. Co-expression networks can serve as great allies in elucidating the possible regulatory contexts in which these molecules are involved. Herein, we propose the use of the pipeline deposited in the RTN package to build lncRNAs co-expression networks using TCGA breast cancer (BC) cohort data. Worldwide, BC is the most common cancer in women and has great molecular heterogeneity. We identified an enriched co-expression network for the validation of relevant cell processes in the context of BC, including LINC00504. This lncRNA has increased expression in luminal subtype A samples, and is associated with prognosis in basal-like subtype. Silencing this lncRNA in luminal A cell lines resulted in decreased cell viability and colony formation. These results highlight the relevance of the proposed method for the identification of lncRNAs in specific biological contexts.

LINC00504 Promotes the Malignant Biological Behavior of Breast Cancer Cells by Upregulating HMGB3 via Decoying MicroRNA-876-3p

Purpose

Long intergenic non-protein coding RNA 504 (LINC00504) is a long non-coding RNA that has an important regulatory role in a variety of human cancers. In this study, LINC00504 expression in breast cancer tissues and cell lines was detected. Studies were also conducted to determine the impact of LINC00504 on the tumor behavior of breast cancer cells. The potential mechanisms underlying the oncogenic role of LINC00504 in breast cancer cells were elucidated in detail.

Methods

Expression of LINC00504 in breast cancer was analyzed by quantitative real-time polymerase chain reaction. The effects of LINC00504 on proliferation, apoptosis, in vitro migration and invasion, and in vivo tumor growth were elucidated using Cell Counting Kit-8 assay, flow cytometry, Transwell assays, and tumor xenograft models, respectively. Bioinformatics analyses in conjunction with RNA immunoprecipitation, luciferase reporter assays, and rescue experiments were conducted to investigate the underlying molecular mechanisms.

Results

LINC00504 was upregulated in breast cancer tissues and cell lines. Knocking down LINC00504 suppressed breast cancer cell proliferation, migration, and invasion and facilitated apoptosis in vitro. In addition, tumor growth in vivo was significantly inhibited by LINC00504 depletion. Regarding the underlying mechanism, LIN00504 could function as a competing endogenous RNA in breast cancer by sponging microRNA-876-3p (miR-876-3p), resulting in the upregulation of high mobility group box 3 (HMGB3). Rescue experiments further revealed that miR-876-3p downregulation or HMGB3 upregulation effectively reversed the inhibitory effects of LIN00504 deficiency on breast cancer cells.

Conclusion

The LIN00504-miR-876-3p-HMGB3 axis shows carcinogenic effects in modulating the biological behavior of breast cancer cells. This pathway may represent an effective target for CRC diagnosis and anticancer therapy.

Circ_0056285 Regulates Proliferation, Apoptosis and Glycolysis of Osteosarcoma Cells via miR-1244/TRIM44 Axis

Background

Osteosarcoma (OS) is a common malignant bone cancer that occurs in adolescents and children. Circular RNAs (circRNAs) are important regulators of tumorigenesis and development. This study aimed to explore the role and molecular basis of circ_0056285 in OS.

Methods

The levels of circ_0056285, miR-1244 and tripartite motif containing 44 (TRIM44) were determined by quantitative real-time polymerase chain reaction or Western blot assay. Cell proliferation was evaluated by Cell Counting Kit-8 (CCK-8) assay and colony formation assay. Cell apoptosis was assessed by flow cytometry and caspase 3and caspase 9 activity assay kits. Glucose uptake, lactate product and ATP level were examined using commercial kits. Hexokinase II (HK2) and lactate dehydrogenase A (LDHA) levels were measured by Western blot assay. The interaction among circ_0056285, miR-1244 and TRIM44 was confirmed by dual-luciferase reporter assay, RNA immunoprecipitation assay or RNA pull-down assay. Xenograft experiment was conducted to explore tumor growth in vivo. Exosomes were identified by transmission electron microscope (TEM), nanoparticle tracking analysis (NTA) and Western blot. The diagnostic value of exosomal circ_0056285 was evaluated by receiver operating characteristic (ROC) curve.

Results

Circ_0056285 and TRIM44 were up-regulated, and miR-1244 was down-regulated in OS tissues and cells. Circ_0056285 silencing inhibited proliferation and glycolysis and promoted apoptosis in OS cells. Also, circ_0056285 knockdown hindered proliferation and accelerated apoptosis in OS cells by regulating miR-1244/TRIM44 axis. Circ_0056285 depletion impeded tumor growth in vivo. Furthermore, ROC curve showed that circ_0056285 might be a diagnostic biomarker in OS.

Conclusion

Circ_0056285 facilitated OS progression by sponging miR-1244 and increasing TRIM44 expression, providing a promising therapeutic target for OS.

The Role of PKM2 in Metabolic Reprogramming: Insights into the Regulatory Roles of Non-Coding RNAs

Pyruvate kinase is a key regulator in glycolysis through the conversion of phosphoenolpyruvate (PEP) into pyruvate. Pyruvate kinase exists in various isoforms that can exhibit diverse biological functions and outcomes. The pyruvate kinase isoenzyme type M2 (PKM2) controls cell progression and survival through the regulation of key signaling pathways. In cancer cells, the dimer form of PKM2 predominates and plays an integral role in cancer metabolism. This predominance of the inactive dimeric form promotes the accumulation of phosphometabolites, allowing cancer cells to engage in high levels of synthetic processing to enhance their proliferative capacity. PKM2 has been recognized for its role in regulating gene expression and transcription factors critical for health and disease. This role enables PKM2 to exert profound regulatory effects that promote cancer cell metabolism, proliferation, and migration. In addition to its role in cancer, PKM2 regulates aspects essential to cellular homeostasis in non-cancer tissues and, in some cases, promotes tissue-specific pathways in health and diseases. In pursuit of understanding the diverse tissue-specific roles of PKM2, investigations targeting tissues such as the kidney, liver, adipose, and pancreas have been conducted. Findings from these studies enhance our understanding of PKM2 functions in various diseases beyond cancer. Therefore, there is substantial interest in PKM2 modulation as a potential therapeutic target for the treatment of multiple conditions. Indeed, a vast plethora of research has focused on identifying therapeutic strategies for targeting PKM2. Recently, targeting PKM2 through its regulatory microRNAs, long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) has gathered increasing interest. Thus, the goal of this review is to highlight recent advancements in PKM2 research, with a focus on PKM2 regulatory microRNAs and lncRNAs and their subsequent physiological significance.

Knockdown of LINC00504 Inhibits the Proliferation and Invasion of Breast Cancer via the Downregulation of miR-140-5p

INTRODUCTION

Breast cancer is one of the most common cancers in the world. Long noncoding RNA 00504 (LINC00504) was reported to be a functional gene in some tumours but not breast. Accordingly, the purpose of this article is to study the function of LINC00504 in breast cancer.

METHODS

qPCR assay was used to detect the expression of LINC00504 in tissue and cell lines. The online database and chromatin immunoprecipitation assay (ChIP) were employed to confirm the transcription factor of LINC00504. Cell function assays including cell proliferation, migration and invasion were designed to detect the function of LINC00504 in vitro and in vivo. Luciferase reporter assay and RNA immunoprecipitation (RIP) assay were used to confirm the relationship between LINC00504 and miR-140-5p. And Western blot assay was employed for testing the key protein.

RESULTS

We found that LINC00504 is upregulated in breast cancer. In addition, we found that the transcription factor regulatory factor X5 (RFX5) can strongly bind to the LINC00504 promoter region and subsequently increase its transcriptional activity. We also found that the manipulation of RFX5 expression can significantly affect LINC00504 expression, which suggested that RFX5 can transcriptionally activate LINC00504 in breast cancer (BC). Knockdown of LINC00504 inhibits cell proliferation, migration and invasion in vitro and in vivo. We further found that LINCOO504 inhibits miR-140-5p, which decreases the levels of VEGFA. The further results showed that miR-140-5p was one of the target gene of LINC00504. The WB assay demonstrated that the E-cadherin was increased and Vimentin was decreased when knocking down of LINC00504 and they can be rescued while adding the inhibitors of miR-140-5p.

DISCUSSION

Our results demonstrated the mechanism by which the LINC00504-miR-140-5p-VEGFA axis participates in breast cancer cell proliferation and invasion and may lead to new lncRNA-based diagnostic or therapeutic strategies for breast cancer.

LncRNAs in Ovarian Cancer Progression, Metastasis, and Main Pathways: ceRNA and Alternative Mechanisms

Ovarian cancer (OvCa) develops asymptomatically until it reaches the advanced stages with metastasis, chemoresistance, and poor prognosis. Our review focuses on the analysis of regulatory long non-coding RNAs (lncRNAs) competing with protein-coding mRNAs for binding to miRNAs according to the model of competitive endogenous RNA (ceRNA) in OvCa. Analysis of publications showed that most lncRNAs acting as ceRNAs participate in OvCa progression: migration, invasion, epithelial-mesenchymal transition (EMT), and metastasis. More than 30 lncRNAs turned out to be predictors of survival and/or response to therapy in patients with OvCa. For a number of oncogenic (CCAT1, HOTAIR, NEAT1, and TUG1 among others) and some suppressive lncRNAs, several lncRNA/miRNA/mRNA axes were identified, which revealed various functions for each of them. Our review also considers examples of alternative mechanisms of actions for lncRNAs besides being ceRNAs, including binding directly to mRNA or protein, and some of them (DANCR, GAS5, MALAT1, and UCA1 among others) act by both mechanisms depending on the target protein. A systematic analysis based on the data from literature and Panther or KEGG (Kyoto Encyclopedia of Genes and Genomes) databases showed that a significant part of lncRNAs affects the key pathways involved in OvCa metastasis, EMT, and chemoresistance.

Exploring the Roles of lncRNAs in GBM Pathophysiology and Their Therapeutic Potential

Glioblastoma (GBM) remains the most devastating primary central nervous system malignancy with a median survival of around 15 months. The past decades of research have not yielded significant advancements in the treatment of GBM. In that same time, a novel class of molecules, long non-coding RNAs (lncRNAs), has been found to play a multitude of roles in cancer and normal biology. The increased accessibility of next generation sequencing technologies and the advent of lncRNA-specific microarrays have facilitated the study of lncRNA etiology. Molecular and computational methods can be applied to predict lncRNA function. LncRNAs can serve as molecular decoys, scaffolds, super-enhancers, or repressors. These molecules can serve as phenotypic switches for GBM cells at the expression and/or epigenetic levels. LncRNAs can affect stemness/differentiation, proliferation, invasion, survival, DNA damage response, and chromatin dynamics. Aberrant expression of these transcripts may facilitate therapy resistance, leading to tumor recurrence. LncRNAs could serve as novel theragnostic or prognostic biomarkers in GBM and other cancers. RNA-based therapeutics may also be employed to target lncRNAs as a novel route of treatment for primary or recurrent GBM. In this review, we explore the roles of lncRNAs in GBM pathophysiology and posit their novel therapeutic potential for GBM.

Regulation of Glycolysis by Non-coding RNAs in Cancer: Switching on the Warburg Effect

The “Warburg effect” describes the reprogramming of glucose metabolism away from oxidative phosphorylation toward aerobic glycolysis, and it is one of the hallmarks of cancer cells. Several factors can be involved in this process, but in this review, the roles of non-coding RNAs (ncRNAs) are highlighted in several types of human cancer. ncRNAs, including microRNAs, long non-coding RNAs, and circular RNAs, can all affect metabolic enzymes and transcription factors to promote glycolysis and modulate glucose metabolism to enhance the progression of tumors. In particular, the 5′-AMP-activated protein kinase (AMPK) and the phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathways are associated with alterations in ncRNAs. A better understanding of the roles of ncRNAs in the Warburg effect could ultimately lead to new therapeutic approaches for suppressing cancer.

Silencing LINC00504 inhibits cell proliferation, invasion as well as migration and promotes cell apoptosis in lung cancer cells via upregulating miR-876-3p

LINC00504 acts as an oncogene and associates with unfavorable prognosis in patients with lung cancer. Silencing LINC00504 may be a promising strategy for treatment of lung cancer and its effects were firstly investigated in lung cancer cells this study. The gene expression level of miR-876-3p as well as LINC00504 were measured via PCR assay. The cell proliferation was investigated through Cell Counting Kit-8 (CCK-8) assay and colony formation assay. Flow cytometry was applied for detection of cell apoptosis. Wound healing and transwell assay were performed for measurement of cell migration and invasion respectively. The apoptosis related protein expressions were measured by western blot. Luciferase report assay was conducted for verification the target gene. LINC00504 was higher expressed in five types of lung cancer cells studied herein when compared with the control normal cells. LINC00504 knockdown exerted inhibitory effects on cell apoptosis, cell migration as well as cell invasion and promoted cell apoptosis. All the effects mentioned above were counteracted by miR-876-3p inhibitor. Silencing LINC00504 possessed anti-proliferation, repression of cell invasion as well as migration and pro-apoptosis effects via targeting up-regulation of miR-876-3p in lung cancer cells, proving the new therapeutic targets and highlighting the potential application in future diagnosis and treatment in lung cancer.

Long noncoding RNA LINC01391 restrained gastric cancer aerobic glycolysis and tumorigenesis via targeting miR-12116/CMTM2 axis

Increasing studies indicate that long noncoding RNA (lncRNA) plays a critical role in aerobic glycolysis of various tumors. However, the contribution of lncRNA in gastric cancer (GC) cell glycolysis is still poorly understood. The objective of this research was to investigate the functional role and mechanism of lncRNA long intergenic non-protein coding RNA 1391 (LINC01391) in the aerobic glycolysis and tumorigenesis of GC. Here, we report that LINC01391 was low expressed in GC tissues and cell lines. LINC01391 overexpression hampered GC cell proliferation, migration, invasion and aerobic glycolysis, while LINC01391 knockdown demonstrated the opposite effects. LINC01391 overexpression delayed the tumor growth in vivo. Furthermore, LINC01391 interacted with miR-12116, and miR-12116 interacted with CMTM2 in GC cells. And miR-12116 and CMTM2 participated in the inhibitory effects of LINC01391 on cell migration, invasion and aerobic glycolysis in GC cells. LINC01391 restrained aerobic glycolysis and tumorigenesis of GC via targeting miR-12116/CMTM2 axis, which provides new insights into mechanism of GC progression.

The Challenges and Opportunities of LncRNAs in Ovarian Cancer Research and Clinical Use

Ovarian cancer is one of the most lethal gynecological malignancies worldwide because it tends to be detected late, when the disease has already spread, and prognosis is poor. In this review we aim to highlight the importance of long non-coding RNAs (lncRNAs) in diagnosis, prognosis and treatment choice, to make progress towards increasingly personalized medicine in this malignancy. We review the effects of lncRNAs associated with ovarian cancer in the context of cancer hallmarks. We also discuss the molecular mechanisms by which lncRNAs become involved in cellular physiology; the onset, development and progression of ovarian cancer; and lncRNAs' regulatory mechanisms at the transcriptional, post-transcriptional and post-translational stages of gene expression. Finally, we compile a series of online resources useful for the study of lncRNAs, especially in the context of ovarian cancer. Future work required in the field is also discussed along with some concluding remarks.

Suppressed "Warburg Effect" in Nasopharyngeal Carcinoma Via the Inhibition of Pyruvate Kinase Type M2-Mediated Energy Generation Pathway

Warburg effect describes the abnormal energy metabolism in cancer cells and pyruvate kinase type M2 is involved in the regulation of this effect. In the current study, the role of pyruvate kinase type M2 in the initiation of Warburg effect in nasopharyngeal carcinoma cells was explored. The expression status of pyruvate kinase type M2 was detected in nasopharyngeal carcinoma samples and analyzed by different clinicopathological characteristics. Then the level of pyruvate kinase type M2 was suppressed in 2 nasopharyngeal carcinoma cell lines. The effects of pyruvate kinase type M2 inhibition on cell viability, apoptosis, invasion, glucose uptake, ATP generation, and glycolysis metabolism were determined. The data showed that the high expression of pyruvate kinase type M2 in nasopharyngeal carcinoma tissues was associated with the larger tumor size and advanced metastasis in the patients. The inhibition of pyruvate kinase type M2 resulted in the repressed proliferation and invasion in nasopharyngeal carcinoma cells, along with the increased apoptotic rate. The lack of pyruvate kinase type M2 function inhibited glucose uptake, while increased ATP generation in nasopharyngeal carcinoma cells. Moreover, the production of glycolysis metabolites, including pyruvic acid, lactate, citrate, and malate, was also suppressed by pyruvate kinase type M2 inhibition. At molecular level, the expressions of glucose transporter and hexokinase 2 were downregulated by pyruvate kinase type M2 inhibition, confirming the changes in glucose metabolism. Collectively, the current study demonstrated that the function of pyruvate kinase type M2 was important to maintain the proliferation and invasion of nasopharyngeal carcinoma cells, and the inhibition of the factor would antagonize nasopharyngeal carcinoma by blocking Warburg effect.