Small ring has big potential: insights into extrachromosomal DNA in cancer

AbstractRecent technical advances have led to the discovery of novel functions of extrachromosomal DNA (ecDNA) in multiple cancer types. Studies have revealed that cancer-associated ecDNA shows a unique circular shape and contains oncogenes that are more frequently amplified than that in linear chromatin DNA. Importantly, the ecDNA-mediated amplification of oncogenes was frequently found in most cancers but rare in normal tissues. Multiple reports have shown that ecDNA has a profound impact on oncogene activation, genomic instability, drug sensitivity, tumor heterogeneity and tumor immunology, therefore may offer the potential for cancer diagnosis and therapeutics. Nevertheless, the underlying mechanisms and future applications of ecDNA remain to be determined. In this review, we summarize the basic concepts, biological functions and molecular mechanisms of ecDNA. We also provide novel insights into the fundamental role of ecDNA in cancer.

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NOB1: A Potential Biomarker or Target in Cancer

Current Drug Targets ◽

10.2174/1389450120666190308145346 ◽

2019 ◽

Vol 20 (10) ◽

pp. 1081-1089

Author(s):

Weiwei Ke ◽

Zaiming Lu ◽

Xiangxuan Zhao

Keyword(s):

Cancer Treatment ◽

Molecular Mechanisms ◽

Rna Binding ◽

Binding Protein ◽

Tumor Development ◽

Anticancer Therapy ◽

Research Progress ◽

Normal Tissues ◽

Potential Biomarker

Human NIN1/RPN12 binding protein 1 homolog (NOB1), an RNA binding protein, is expressed ubiquitously in normal tissues such as the lung, liver, and spleen. Its core physiological function is to regulate protease activities and participate in maintaining RNA metabolism and stability. NOB1 is overexpressed in a variety of cancers, including pancreatic cancer, non-small cell lung cancer, ovarian cancer, prostate carcinoma, osteosarcoma, papillary thyroid carcinoma, colorectal cancer, and glioma. Although existing data indicate that NOB1 overexpression is associated with cancer growth, invasion, and poor prognosis, the molecular mechanisms behind these effects and its exact roles remain unclear. Several studies have confirmed that NOB1 is clinically relevant in different cancers, and further research at the molecular level will help evaluate the role of NOB1 in tumors. NOB1 has become an attractive target in anticancer therapy because it is overexpressed in many cancers and mediates different stages of tumor development. Elucidating the role of NOB1 in different signaling pathways as a potential cancer treatment will provide new ideas for existing cancer treatment methods. This review summarizes the research progress made into NOB1 in cancer in the past decade; this information provides valuable clues and theoretical guidance for future anticancer therapy by targeting NOB1.

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The Role of Extracellular Vesicles in the Development of a Cancer Stem Cell Microenvironment Niche and Potential Therapeutic Targets

Cancers ◽

10.3390/cancers13102435 ◽

2021 ◽

Vol 13 (10) ◽

pp. 2435

Author(s):

Thomas J. Brown ◽

Victoria James

Keyword(s):

Systematic Review ◽

Tumor Microenvironment ◽

Extracellular Vesicles ◽

Multiple Cancer ◽

Therapeutic Targeting ◽

Small Component ◽

Facilitated Communication ◽

Cell Microenvironment ◽

Cancer Types

Cancer stem cells (CSCs) have increasingly been shown to be a crucial element of heterogenous tumors. Although a relatively small component of the population, they increase the resistance to treatment and the likelihood of recurrence. In recent years, it has been shown, across multiple cancer types (e.g., colorectal, breast and prostate), that reciprocal communication between cancer and the microenvironment exists, which is, in part, facilitated by extracellular vesicles (EVs). However, the mechanisms of this method of communication and its influence on CSC populations is less well-understood. Therefore, the aim of this systematic review is to determine the evidence that supports the role of EVs in the manipulation of the tumor microenvironment to promote the survival of CSCs. Embase and PubMed were used to identify all studies on the topic, which were screened using PRISMA guidelines, resulting in the inclusion of 16 studies. These 16 studies reported on the EV content, pathways altered by EVs and therapeutic targeting of CSC through EV-mediated changes to the microenvironment. In conclusion, these studies demonstrated the role of EV-facilitated communication in maintaining CSCs via manipulation of the tumor microenvironment, demonstrating the potential of creating therapeutics to target CSCs. However, further works are needed to fully understand the targetable mechanisms upon which future therapeutics can be based.

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Regulatory Role of microRNAs Targeting the Transcription Co-Factor ZNF521 in Normal Tissues and Cancers

International Journal of Molecular Sciences ◽

10.3390/ijms22168461 ◽

2021 ◽

Vol 22 (16) ◽

pp. 8461

Author(s):

Emanuela Chiarella ◽

Annamaria Aloisio ◽

Stefania Scicchitano ◽

Heather Mandy Bond ◽

Maria Mesuraca

Keyword(s):

Transcription Factor ◽

Molecular Mechanisms ◽

Transitional Cell ◽

Biological Functions ◽

Aberrant Expression ◽

Normal Tissues ◽

Novel Mirna ◽

Mirna Expression Profiling ◽

Mirna Deregulation

Powerful bioinformatics tools have provided a wealth of novel miRNA–transcription factor networks crucial in controlling gene regulation. In this review, we focus on the biological functions of miRNAs targeting ZNF521, explaining the molecular mechanisms by which the dysregulation of this axis contributes to malignancy. ZNF521 is a stem cell-associated co-transcription factor implicated in the regulation of hematopoietic, neural, and mesenchymal stem cells. The aberrant expression of ZNF521 transcripts, frequently associated with miRNA deregulation, has been detected in several tumors including pancreatic, hepatocellular, gastric, bladder transitional cell carcinomas as well as in breast and ovarian cancers. miRNA expression profiling tools are currently identifying a multitude of miRNAs, involved together with oncogenes and TFs in the regulation of oncogenesis, including ZNF521, which may be candidates for diagnostic and prognostic biomarkers of cancer.

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The Pathogenic Role of PI3K/AKT Pathway in Cancer Onset and Drug Resistance: An Updated Review

Cancers ◽

10.3390/cancers13163949 ◽

2021 ◽

Vol 13 (16) ◽

pp. 3949

Author(s):

Federica Rascio ◽

Federica Spadaccino ◽

Maria Teresa Rocchetti ◽

Giuseppe Castellano ◽

Giovanni Stallone ◽

...

Keyword(s):

Drug Resistance ◽

Akt Pathway ◽

Invasion And Metastasis ◽

Pathogenic Role ◽

Multiple Cancer ◽

Downstream Target ◽

Cancer Types ◽

Multi Level ◽

Survival Mechanisms

The PI3K/AKT pathway is one of the most frequently over-activated intracellular pathways in several human cancers. This pathway, acting on different downstream target proteins, contributes to the carcinogenesis, proliferation, invasion, and metastasis of tumour cells. A multi-level impairment, involving mutation and genetic alteration, aberrant regulation of miRNAs sequences, and abnormal phosphorylation of cascade factors, has been found in multiple cancer types. The deregulation of this pathway counteracts common therapeutic strategies and contributes to multidrug resistance. In this review, we underline the involvement of this pathway in patho-physiological cell survival mechanisms, emphasizing its key role in the development of drug resistance. We also provide an overview of the potential inhibition strategies currently available.

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MicroRNA-1225-5p acts as a tumor-suppressor in laryngeal cancer via targeting CDC14B

Biological Chemistry ◽

10.1515/hsz-2018-0265 ◽

2019 ◽

Vol 400 (2) ◽

pp. 237-246 ◽

Cited By ~ 9

Author(s):

Peng Sun ◽

Dan Zhang ◽

Haiping Huang ◽

Yafeng Yu ◽

Zhendong Yang ◽

...

Keyword(s):

Cell Cycle ◽

Cell Death ◽

Cell Division ◽

Cell Cycle Arrest ◽

Molecular Mechanisms ◽

Normal Tissues ◽

Cycle Arrest ◽

Enhanced Expression ◽

Insight Into

Abstract This study aimed to investigate the role of miRNA-1225-5p (miR-1225) in laryngeal carcinoma (LC). We found that the expression of miR-1225 was suppressed in human LC samples, while CDC14B (cell division cycle 14B) expression was reinforced in comparison with surrounding normal tissues. We also demonstrated that enhanced expression of miR-1225 impaired the proliferation and survival of LC cells, and resulted in G1/S cell cycle arrest. In contrast, reduced expression of miR-1225 promoted cell survival. Moreover, miR-1225 resulted in G1/S cell cycle arrest and enhanced cell death. Further, miR-1225 targets CDC14B 3′-UTR and recovery of CDC14B expression counteracted the suppressive influence of miR-1225 on LC cells. Thus, these findings offer insight into the biological and molecular mechanisms behind the development of LC.

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Revisiting the Hygiene Hypothesis in the Context of Autoimmunity

Frontiers in Immunology ◽

10.3389/fimmu.2020.615192 ◽

2021 ◽

Vol 11 ◽

Author(s):

Jean-François Bach

Keyword(s):

Molecular Mechanisms ◽

Epidemiological Data ◽

Allergic Diseases ◽

Hygiene Hypothesis ◽

Interleukin 10 ◽

Major Question ◽

Important Place ◽

Immunoregulatory Cytokines ◽

Underlying Mechanisms

Initially described for allergic diseases, the hygiene hypothesis was extended to autoimmune diseases in the early 2000s. A historical overview allows appreciation of the development of this concept over the last two decades and its discussion in the context of evolution. While the epidemiological data are convergent, with a few exceptions, the underlying mechanisms are multiple and complex. A major question is to determine what is the respective role of pathogens, bacteria, viruses, and parasites, versus commensals. The role of the intestinal microbiota has elicited much interest, but is it a cause or a consequence of autoimmune-mediated inflammation? Our hypothesis is that both pathogens and commensals intervene. Another question is to dissect what are the underlying cellular and molecular mechanisms. The role of immunoregulatory cytokines, in particular interleukin-10 and TGF beta is probably essential. An important place should also be given to ligands of innate immunity receptors present in bacteria, viruses or parasites acting independently of their immunogenicity. The role of Toll-Like Receptor (TLR) ligands is well documented including via TLR ligand desensitization.

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Pan-Cancer Prognostic, Immunity, Stemness, and Anticancer Drug Sensitivity Characterization of N6-Methyladenosine RNA Modification Regulators in Human Cancers

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2021.644620 ◽

2021 ◽

Vol 8 ◽

Author(s):

Rui Li ◽

Yun-Hong Yin ◽

Xiu-Li Ji ◽

Xiao Liu ◽

Jian-Ping Li ◽

...

Keyword(s):

Tumor Microenvironment ◽

Anticancer Drug ◽

Drug Sensitivity ◽

Rna Modification ◽

Immune Microenvironment ◽

Normal Tissues ◽

Tumor Immune Microenvironment ◽

Cancer Types ◽

Pan Cancer

N6-methyladenosine RNA modification plays a significant role in the progression of multiple tumorigenesis. Our study identified the imperative role of m6A regulators in the tumor immune microenvironment, survival, stemness score, and anticancer drug sensitivity of pan-cancer. The Wilcox test was to identify the differential expression between 17 m6A regulators across 33 TCGA cancer types and their normal tissues from UCSC Xena GDC pan-cancer. Survival analysis of m6A-related regulators in 33 TCGA cancer types was identified using the “survival” and “survminer” package. The Spearman correlation test and Pearson correlation test were used to identify the correlation relationship between m6A regulators expression and tumor microenvironment, tumor stem cell score, and drug sensitivity of anticancer drugs. ConsensusPathDB was used for exploring m6A regulators functional enrichment. The 17 (METTL3, WTAP, METTL14, RBM15, RBM15B, VIRMA, HNRNPC, HNRNPA2B1, YTHDC1, ZC3H13, YTHDF1, YTHDC2, YTHDF2, IGF2BP3, IGF2BP1, FTO, and ALKBH5) m6A regulators were differentially expressed in 18 TCGA cancer types and adjacent normal tissues. Correlation analysis indicated that the relationship between the expression of 17 m6A regulators and tumor microenvironment indicated that the higher expression of m6A regulators, the higher the degree of tumor stem cells. The anticancer drug sensitivity analysis indicated that ZC3H13 expression had a positive relationship with anticancer drugs such as selumetinib, dabrafenib, cobimetinib, trametinib, and hypothemycin (p < 0.001). YTHDF2 expression was significantly negatively correlated with the anticancer drug dasatinib (p < 0.001). The pan-cancer immune subtype analysis showed that the 17 m6A regulators were significantly different in immune subtype C1 (wound healing), C3 (inflammatory), C2 (IFN-gamma dominant), C5 (immunological quiet), C4 (lymphocyte depleted), and C6 (TGF-beta dominant) (p < 0.001). Our study provides a comprehensive insight for revealing the significant role of m6A regulators in the tumor immune microenvironment, stemness score, and anticancer drug sensitivity of human cancers.

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Role of the Ubiquitin System in Chronic Pain

Frontiers in Molecular Neuroscience ◽

10.3389/fnmol.2021.674914 ◽

2021 ◽

Vol 14 ◽

Author(s):

Jiurong Cheng ◽

Yingdong Deng ◽

Jun Zhou

Keyword(s):

Chronic Pain ◽

Molecular Mechanisms ◽

Therapeutic Targets ◽

Public Health Issue ◽

Deubiquitinating Enzyme ◽

Ubiquitin System ◽

Significant Public Health ◽

Underlying Mechanisms ◽

Insight Into

As a significant public health issue, chronic pain, mainly neuropathic pain (NP) and inflammatory pain, has a severe impact. The underlying mechanisms of chronic pain are enigmatic at present. The roles of ubiquitin have been demonstrated in various physiological and pathological conditions and underscore its potential as therapeutic targets. The dysfunction of the component of the ubiquitin system that occurs during chronic pain is rapidly being discovered. These results provide insight into potential molecular mechanisms of chronic pain. Chronic pain is regulated by ubiquitination, SUMOylation, ubiquitin ligase, and deubiquitinating enzyme (DUB), etc. Insight into the mechanism of the ubiquitin system regulating chronic pain might contribute to relevant therapeutic targets and the development of novel analgesics.

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The Critical Role of Tetrahydrobiopterin (BH4) Metabolism in Modulating Radiosensitivity: BH4/NOS Axis as an Angel or a Devil

Frontiers in Oncology ◽

10.3389/fonc.2021.720632 ◽

2021 ◽

Vol 11 ◽

Author(s):

Yang Feng ◽

Yahui Feng ◽

Liming Gu ◽

Pengfei Liu ◽

Jianping Cao ◽

...

Keyword(s):

Nitric Oxide ◽

Free Radicals ◽

Ionizing Radiation ◽

Molecular Mechanisms ◽

De Novo ◽

Antiangiogenic Therapy ◽

Critical Role ◽

Cellular Radiosensitivity ◽

Normal Tissues

Ionizing radiation and radioactive materials have been widely used in industry, medicine, science and military. The efficacy of radiotherapy and adverse effects of normal tissues are closed related to cellular radiosensitivity. Molecular mechanisms underlying radiosensitivity are of significance to tumor cell radiosensitization as well as normal tissue radioprotection. 5,6,7,8-Tetrahydrobiopterin (BH4) is an essential cofactor for nitric oxide synthases (NOS) and aromatic amino acid hydroxylases, and its biosynthesis involves de novo biosynthesis and a pterin salvage pathway. In this review we overview the role of BH4 metabolism in modulating radiosensitivity. BH4 homeostasis determines the role of NOS, affecting the production of nitric oxide (NO) and oxygen free radicals. Under conditions of oxidative stress, such as UV-radiation and ionizing radiation, BH4 availability is diminished due to its oxidation, which subsequently leads to NOS uncoupling and generation of highly oxidative free radicals. On the other hand, BH4/NOS axis facilitates vascular normalization, a process by which antiangiogenic therapy corrects structural and functional flaws of tumor blood vessels, which enhances radiotherapy efficacy. Therefore, BH4/NOS axis may serve as an angel or a devil in regulating cellular radiosensitivity. Finally, we will address future perspectives, not only from the standpoint of perceived advances in treatment, but also from the potential mechanisms. These advances have demonstrated that it is possible to modulate cellular radiosensitivity through BH4 metabolism.

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SALL4 and microRNA: The Role of Let-7

Genes ◽

10.3390/genes12091301 ◽

2021 ◽

Vol 12 (9) ◽

pp. 1301

Author(s):

Jun Liu ◽

Madeline A. Sauer ◽

Shaza Hussein ◽

Junyu Yang ◽

Daniel G. Tenen ◽

...

Keyword(s):

Stem Cells ◽

Embryonic Stem ◽

Mammalian Development ◽

Multiple Cancer ◽

Self Renewal ◽

Zinc Finger Transcription Factor ◽

Different Types ◽

Organ Specific ◽

Cancer Types

SALL4 is a zinc finger transcription factor that belongs to the spalt-like (SALL) gene fam-ily. It plays important roles in the maintenance of self-renewal and pluripotency of embryonic stem cells, and its expression is repressed in most adult organs. SALL4 re-expression has been observed in different types of human cancers, and dysregulation of SALL4 contributes to the pathogenesis, metastasis, and even drug resistance of multiple cancer types. Surprisingly, little is known regard-ing how SALL4 expression is controlled, but recently microRNAs (miRNAs) have emerged as im-portant regulators of SALL4. Due to the ability of regulating targets differentially in specific tissues, and recent advances in systemic and organ specific miRNA delivery mechanisms, miRNAs have emerged as promising therapeutic targets for cancer treatment. In this review, we summarize cur-rent knowledge of the interaction between SALL4 and miRNAs in mammalian development and cancer, paying particular attention to the emerging roles of the Let-7/Lin28 axis. In addition, we discuss the therapeutic prospects of targeting SALL4 using miRNA-based strategies, with a focus on the Let-7/LIN28 axis.

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