CircHIPK3 Promotes the Tumorigenesis and Development of Gastric Cancer Through miR-637/AKT1 Pathway

DNA Framework-Based Programmable Atom-Like Nanoparticles for Non-Coding RNA Recognition and Differentiation of Cancer Cells

The cooperative diagnosis of non-coding RNAs (ncRNAs) can accurately reflect the state of cell differentiation and classification, laying the foundation of precision medicine. However, there are still challenges in simultaneous analyses of multiple ncRNAs and the integration of biomarker data for cell typing. In this study, DNA framework-based programmable atom-like nanoparticles (PANs) are designed to develop molecular classifiers for intra-cellular imaging of multiple ncRNAs associated with cell differentiation. The PANs-based molecular classifier facilitates signal amplification through the catalytic hairpin assembly. The interaction between PAN reporters and ncRNAs enables high-fidelity conversion of ncRNAs expression level into binding events, and the assessment of in situ ncRNAs levels via measurement of the fluorescent signal changes of PAN reporters. Compared to non-amplified methods, the detection limits of PANs are reduced by four orders of magnitude. Using human gastric cancer cell lines as a model system, the PANs-based molecular classifier demonstrates its capacity to measure multiple ncRNAs in living cells and assesses the degree of cell differentiation. This approach can serve as a universal strategy for the classification of cancer cells during malignant transformation and tumor progression.

Circ_0000877 accelerates proliferation and immune escape of non-small cell lung cancer cells by regulating microRNA-637/E2F2 axis

BACKGROUND

Recently, circular RNA (circRNA) has become a vital targeted therapy gene for non-small-cell lung cancer (NSCLC) cells. CircRNA_0000877 (Circ_0000877) has been researched in diffuse large B-cell lymphoma (DLBCL). However, whether circ_0000877 regulated NSCLC cell progression is still poorly investigated. The research attempted to investigate the influence of circ_0000877 in NSCLC.

METHODS

Circ_0000877 levels in NSCLC tissues and cell lines were determined applying RT-qPCR. Cell functions were evaluated by CCK-8, EdU, flow cytometry, ELISA, and western blot. Gene interactions were predicted by Cirular RNA interactome database and Target Scan website and certified by dual-luciferase reporter, RIP, and RNA pull-down assays. Finally, mice experimental model was established to explore the effects of circ_0000877 on tumor growth in vivo.

RESULTS

The elevated trend of circ_0000877 expression was discovered in NSCLC tissues compared to para-carcinoma tissues. The clinicopathological data uncovered that up-regulated circ_0000877 was linked to tumor size, differentiation, and TNM stages of NSCLC patients. Knockdown of circ_0000877 inhibited the proliferation, triggered apoptosis, and prohibited immune escape in NSCLC cells. It was certified that miR-637 was directly interacted with circ_0000877 and targeted by E2F2. Overexpressed E2F2 strongly overturned the functions of circ_0000877 knockdown in NSCLC cells. Mice experimental data demonstrated that circ_0000877 knockdown suppressed tumor growth in vivo.

CONCLUSION

The research demonstrated that circ_0000877 exhibited the promotive effect on NSCLC cells proliferation and immune escape by regulating miR-637/E2F2 axis.

Profiling Kinase Activities for Precision Oncology in Diffuse Gastric Cancer

Gastric cancer (GC) remains a leading cause of cancer-related mortality globally. This is due to the fact that majority of the cases of GC are diagnosed at an advanced stage when the treatment options are limited and prognosis is poor. The diffuse subtype of gastric cancer (DGC) under Lauren's classification is more aggressive and usually occurs in younger patients than the intestinal subtype. The concept of personalized medicine is leading to the identification of multiple biomarkers in a large variety of cancers using different combinations of omics technologies. Proteomic changes including post-translational modifications are crucial in oncogenesis. We analyzed the phosphoproteome of DGC by using paired fresh frozen tumor and adjacent normal tissue from five patients diagnosed with DGC. We found proteins involved in the epithelial-to-mesenchymal transition (EMT), c-MYC pathway, and semaphorin pathways to be differentially phosphorylated in DGC tissues. We identified three kinases, namely, bromodomain adjacent to the zinc finger domain 1B (BAZ1B), WNK lysine-deficient protein kinase 1 (WNK1), and myosin light-chain kinase (MLCK) to be hyperphosphorylated, and one kinase, AP2-associated protein kinase 1 (AAK1), to be hypophosphorylated. LMNA hyperphosphorylation at serine 392 (S392) was demonstrated in DGC using immunohistochemistry. Importantly, we have detected heparin-binding growth factor (HDGF), heat shock protein 90 (HSP90), and FTH1 as potential therapeutic targets in DGC, as drugs targeting these proteins are currently under investigation in clinical trials. Although these new findings need to be replicated in larger study samples, they advance our understanding of signaling alterations in DGC, which could lead to potentially novel actionable targets in GC.

CircRNAs in colorectal cancer: potential biomarkers and therapeutic targets

Globally, colorectal cancer (CRC) is the third most prevalent cancer and the second leading cause of cancer-related deaths. Circular RNAs (circRNAs) are single-stranded RNA with covalently closed-loop structures and are highly stable, conserved, and abundantly expressed in various organs and tissues. Recent research found abnormal circRNA expression in CRC patients' blood/serum, cells, CRC tissues, and exosomes. Furthermore, mounting data demonstrated that circRNAs are crucial to the development of CRC. CircRNAs have been shown to exert biological functions by acting as microRNA sponges, RNA-binding protein sponges, regulators of gene splicing and transcription, and protein/peptide translators. These characteristics make circRNAs potential markers for CRC diagnosis and prognosis, potential therapeutic targets, and circRNA-based therapies. However, further studies are still necessary to improve the understanding of the roles and biological mechanisms of circRNAs in the development of CRC. In this review, up-to-date research on the role of circRNAs in CRC was examined, focusing on their potential application in CRC diagnosis and targeted therapy, which would advance the knowledge of the functions of circRNAs in the development and progression of CRC.

Role of circRNAs in gastric cancer

Circular RNAs (circRNAs) are a large class of non-coding RNAs with single-strand covalently closed loops, formed by reverse splicing, which widely exist in many cell lines and diverse species. Some circRNAs have highly evolutionarily conserved sequences, or tissue-specific or cell-specific expression patterns, and many circRNAs are extremely stable. In the past decades, accumulating evidence has indicated that circRNAs participate in the mechanisms associated with the development of many kinds of tumors, exert important biological functions by acting as microRNA or protein ‘sponges’, transcriptional regulatory factors, and protein translation templates, and play key roles in the occurrence and development of gastric cancer. This review comprehensively summarizes the biogenesis, characteristics, and biological functions of circRNAs, and the molecular mechanisms underlying the role of circRNAs in the carcinogenesis and progression of gastric cancer.

The Tumorigenic Role of Circular RNA-MicroRNA Axis in Cancer

Circular RNAs (circRNAs) are a class of endogenous RNAs that control gene expression at the transcriptional and post-transcriptional levels. Recent studies have increasingly demonstrated that circRNAs act as novel diagnostic biomarkers and promising therapeutic targets for numerous cancer types by interacting with other non-coding RNAs such as microRNAs (miRNAs). The miRNAs are presented as crucial risk factors and regulatory elements in cancer by regulating the expression of their target genes. Some miRNAs are derived from transposable elements (MDTEs) that can transfer their location to another region of the genome. Genetic interactions between miRNAs and circular RNAs can form complex regulatory networks with various carcinogenic processes that play critical roles in tumorigenesis and cancer progression. This review focuses on the biological regulation of the correlative axis among circular RNAs, miRNAs, and their target genes in various cancer types and suggests the biological importance of MDTEs interacting with oncogenic or tumor-suppressive circRNAs in tumor progression.

Dexmedetomidine promotes ferroptotic cell death in gastric cancer via hsa_circ_0008035/miR-302a/E2F7 axis

Dexmedetomidine (DEX), a common anesthetic, has significant effects on the biological features of cancer cells. Although numerous studies have been published on the impact of DEX on the biological characteristics of GC cells, the mechanism remains unknown. This study aimed to explore the effect of DEX on the biological properties of GC cells. DEX suppressed the viability and increased the apoptosis of GC cells in vitro and inhibited tumor growth in vivo. Besides, DEX raised the levels of reactive oxygen species (ROS) and iron, but decreased the levels of glutathione (GSH), glutathione peroxidase 4 (GPX4), and solute carrier family 7 member 11 (SLC7A11) in GC cells, which were abolished by Ferrostatin-1 (the inhibitor of ferroptosis) treatment. In addition, the level of circ0008035 and E2F7 were downregulated, but miR-302a level was upregulated in DEX-treated GC cells. Circ0008035 increased the expression of E2F2 by acting as a sponge for miR-302a. Circ0008035 inhibited DEX-induced ferroptotic cell death in GC cells, which was reversed by miR-302a overexpression or E2F7 reduction. Taken together, DEX mediated ferroptotic cell death in GC through regulating the circ0008035/miR-302a/E2F7 axis, suggesting a feasible therapy option for GC.

Understanding the Dual Roles of CircHIPK3 in Tumorigenesis and Tumor Progression

CircHIPK3 is a type of endogenous circular RNA, which contains a covalently closed circular structure and cannot encode protein or polypeptide. CircHIPK3 is unusually expressed in varieties of tumors and plays dual roles of tumor promotion or tumor inhibition in tumorigenesis and development of tumors by serving as the sponge for miRNA in multiple tumors. Here, we reviewed the differential expression, the dual functions, the regulation mechanism, and the network in a variety of tumors as well as the potential value for the diagnosis and treatment of tumors, which are of great significance for our comprehensive understanding of the roles and mechanisms of circHIPK3 in tumors.

Circular RNAs as diagnostic biomarkers for gastric cancer: A comprehensive update from emerging functions to clinical significances

The incidence and mortality of gastric cancer ranks as a fouth leading cause of cancer death worldwide, especially in East Asia. Due to the lack of specific early-stage symptoms, the majority of patients in most developing nations are diagnosed at an advanced stage. Therefore, it is urgent to find more sensitive and reliable biomarkers for gastric cancer screening and diagnosis. Circular RNAs (circRNAs), a novel type of RNAs with covalently closed loops, are becoming a latest hot spot in the field of. In recent years, a great deal of research has demonstrated that abnormal expression of circRNAs was associated with the development of gastric cancer, and suggested that circRNA might serve as a potential biomarker for gastric cancer diagnosis. In this review, we summarize the structural characteristics, formation mechanism and biological function of circRNAs, and elucidate research progress and existing problems in early screening of gastric cancer.

The Diagnostic and Therapeutic Role of Circular RNA HIPK3 in Human Diseases

Circular RNAs (circRNAs) are a class of noncoding RNAs with closed-loop of single-stranded RNA structure. Although most of the circRNAs do not directly encode proteins, emerging evidence suggests that circRNAs play a pivotal and complex role in multiple biological processes by regulating gene expression. As one of the most popular circRNAs, circular homeodomain-interacting protein kinase 3 (circHIPK3) has frequently gained the interest of researchers in recent years. Accumulating studies have demonstrated the significant impacts on the occurrence and development of multiple human diseases including cancers, cardiovascular diseases, diabetes mellitus, inflammatory diseases, and others. The present review aims to provide a detailed description of the functions of circHIPK3 and comprehensively overview the diagnostic and therapeutic value of circHIPK3 in these certain diseases.

Dysfunction and ceRNA network of the tumor suppressor miR-637 in cancer development and prognosis

MicroRNAs (miRNAs) are a class of small non-coding RNAs ranging from 17 to 25 nt in length. miR-637 is down-regulated in most cancers and up-regulated only in clear cell renal cell carcinoma (ccRCC). miR-637 can target 21 protein-coding genes, which are involved in the regulation of cell growth, cell cycle, cell proliferation, epithelial-mesenchymal transition (EMT), cancer cell invasion and metastasis, etc. In glioma, the transcription factor ZEB2 can bind to the miR-637 promoter region and inhibit miR-637 expression. Besides, miR-637 could be negatively regulated by competing endogenous RNA (ceRNAs) comprising 13 circular RNA (circRNAs) and 9 long non-coding RNA (lncRNAs). miR-637 is involved in regulating five signaling pathways, including the Jak/STAT3, Wnt/β-catenin, PI3K/AKT, and ERK signaling pathways. Low miR-637 expression was significantly associated with larger tumors and later tumor node metastasis (TNM) staging in cancer patients. Low miR-637 expression was also associated with poorer overall survival (OS) in cancer patients such as glioblastoma and low-grade gliomas (GBM/LGG), non-small cell lung cancer (NSCLC), hepatocellular carcinoma (HCC), and ovarian cancer (OV). Low expression of miR-637 increases the resistance of colorectal cancer (CRC) and human cholangiocarcinoma (CHOL) cancer cells to three anticancer chemotherapeutics (gemcitabine (dFdC), cisplatin (DDP), and oxaliplatin (OXA)). Our work summarizes the abnormal expression of miR-637 in various cancers, expounds on the ceRNA regulatory network and signaling pathway involved in miR-637, and summarizes the effect of its abnormal expression on the biological behavior of tumor cells. At the same time, the relationship between the expression levels of miR-637 and its related molecules and the prognosis and pathological characteristics of patients was further summarized. Finally, our work points out the insufficiency of miR-637 in current studies and is expected to provide potential clues for future miR-637-related studies.

Circular RNA and Its Roles in the Occurrence, Development, Diagnosis of Cancer

Circular RNAs (circRNAs) are non-coding single-stranded covalently closed circular RNA, mainly produced by reverse splicing of exons of precursor mRNAs (pre-mRNAs). The characteristics of high abundance, strong specificity, and good stability of circRNAs have been discovered. A large number of studies have reported its various functions and mechanisms in biological events, such as the occurrence and development of cancer. In this review, we focus on the classification, characterization, biogenesis, functions of circRNAs, and the latest advances in cancer research. The development of circRNAs as biomarkers in cancer diagnosis and treatment also provides new ideas for studying circRNAs research.

circHIPK3 regulates cell proliferation and migration by sponging microRNA-124 and regulating serine/threonine kinase 3 expression in esophageal squamous cell carcinoma

Circular RNAs (circRNAs) are a type of important non-coding RNAs that widely involve in the physiological and pathophysiological process. Recent research has established a link between circHIPK3 and the malignant activity of cancer cells. However, circHIPK3’ role in esophageal squamous cell carcinoma (ESCC) still needs more focus. To determine the prognostic value of circHIPK3 in patients with ESCC, the expression of circHIPK3 was quantified in 32 pairs of ESCC using real-time polymerase chain reaction (RT-qPCR). Then, the correlation between circHIPK3 expression and clinical characteristics of patients was also analyzed. The function of circHIPK3 in the development of ESCC was investigated using cell biology studies and bioinformatics. The results showed that the expression of circHIPK3 was considerably higher in tumor tissues from ESCC patients than that of adjacent tissues, which was associated with a poor prognosis. Additionally, silencing of circHIPK3 expression retarded esophageal cancer cell proliferation, migration and epithelial-mesenchymal transition (EMT) in vitro, as well as the growth in vivo. Mechanistically, we discovered that circHIPK3 behaved like a sponge, absorbing microRNA-124 (miR-124) and promoting serine/threonine kinase 3 (AKT3) expression. Our findings indicate that circHIPK3 acts as an oncogene in ESCC and that the circHIPK3-AKT3 axis may be a therapeutic target for patients with ESCC.

Gastric cancer: An epigenetic view

Gastric cancer (GC) poses a serious threat worldwide with unfavorable prognosis mainly due to late diagnosis and limited therapies. Therefore, precise molecular classification and search for potential targets are required for diagnosis and treatment, as GC is complicated and heterogeneous in nature. Accumulating evidence indicates that epigenetics plays a vital role in gastric carcinogenesis and progression, including histone modifications, DNA methylation and non-coding RNAs. Epigenetic biomarkers and drugs are currently under intensive evaluations to ensure efficient clinical utility in GC. In this review, key epigenetic alterations and related functions and mechanisms are summarized in GC. We focus on integration of existing epigenetic findings in GC for the bench-to-bedside translation of some pivotal epigenetic alterations into clinical practice and also describe the vacant field waiting for investigation.

The Molecular Roles and Clinical Implications of Non-Coding RNAs in Gastric Cancer

Gastric cancer (GC) is one of the most common malignancies in the world. It is also the fifth most common cancer in China. In recent years, a large number of studies have proved that non-coding RNAs (ncRNAs) can regulate cell proliferation, invasion, metastasis, apoptosis, and angiogenesis. NcRNAs also influence the therapeutic resistance of gastric cancer. NcRNAs mainly consist of miRNAs, lncRNAs and circRNAs. In this paper, we summarized ncRNAs as biomarkers and therapeutic targets for gastric cancer, and also reviewed their role in clinical trials and diagnosis. We sum up different ncRNAs and related moleculars and signaling pathway in gastric cancer, like Bcl-2, PTEN, Wnt signaling. In addition, the potential clinical application of ncRNAs in overcoming chemotherapy and radiotherapy resistance in GC in the future were also focused on.

CircRNAs in gastric cancer: current research and potential clinical implications

Gastric cancer (GC) has a dismal prognosis and is also one of the most commonly diagnosed malignancies worldwide. circRNAs are covalently closed circular RNA molecules without 5'-cap and a 3'-tail, currently listed among the broad noncoding RNA family. circRNAs participate in a variety of pathophysiological processes relevant to human diseases, especially malignancies, including GC. Compelling evidence has shown that circRNAs can function by sponging miRNAs, interacting with RNA binding proteins, and encoding proteins or peptides. Yet, our current understanding of these RNA circles remains very limited. Here, we overview the biogenesis, characteristics, functions, and degradation of circRNAs. Moreover, we give an account of the circRNAs that have been linked with GC, describing their functions and mechanisms of action in the context of GC. Next, we discuss the potential value of circRNAs as diagnostic or prognostic GC biomarkers and summarize future prospects, important questions, and challenges of circRNA-based therapeutics.