The role of exosomal non-coding RNAs in cancer metastasis. Oncotarget. 2018;9:12487-12502. [PMID: 29552328 PMCID: PMC5844764 DOI: 10.18632/oncotarget.23552]

Red Blood Cell-Derived Exosomal Oncogenic MicroRNA Promote Cancer Development and Progression

The role of red blood cells (RBCs) in tumorigenesis is poorly understood. We previously identified RBC-microRNAs with aberrations linked to lung cancer, including miR-93-5p. Here we find that miR-93-5p levels are elevated in RBC-derived exosomes among lung cancer patients and are associated with their shorter survivals. RBC-derived miR-93-5p transfers to cancer cells primarily through the exosomal pathway. The transferred RBC-miR-93-5p can target PTEN in cancer cells, and hence increase cell proliferation, invasion, and migration. RBC-derived miR-93-5p accelerates, whereas targeting miR-93-5p diminishes tumor growth in xenograft models. These findings reveal a novel biological function of RBCs in tumorigenesis, where they facilitate cancer progression by transferring the oncomiR via exosomes, thereby offering new diagnostic and treatment strategies for lung cancer.

Exosomal non-coding RNAs: Blueprint in colorectal cancer metastasis and therapeutic targets

Colorectal cancer (CRC) is ranked as the world's third-most prevalent cancer, and metastatic CRC considerably increases cancer-related fatalities globally. A number of complex mechanisms that are strictly controlled at the molecular level are involved in metastasis, which is the primary reason for death in people with CRC. Recently, it has become clear that exosomes, which are small extracellular vesicles released by non-tumorous and tumorigenic cells, play a critical role as communication mediators among tumor microenvironment (TME). To facilitate communication between the TME and cancer cells, non-coding RNAs (ncRNAs) play a crucial role and are recognized as potent regulators of gene expression and cellular processes, such as metastasis and drug resistance. NcRNAs are now recognized as potent regulators of gene expression and many hallmarks of cancer, including metastasis. Exosomal ncRNAs, like miRNAs, circRNAs, and lncRNAs, have been demonstrated to influence a number of cellular mechanisms that contribute to CRC metastasis. However, the molecular mechanisms that link exosomal ncRNAs with CRC metastasis are not well understood. This review highlights the essential roles that exosomal ncRNAs play in the progression of CRC metastatic disease and explores the therapeutic choices that are open to patients who have CRC metastases. However, exosomal ncRNA treatment strategy development is still in its early phases; consequently, additional investigation is required to improve delivery methods and find novel therapeutic targets as well as confirm the effectiveness and safety of these therapies in preclinical and clinical contexts.

Pathological and Therapeutic Significance of Tumor-Derived Extracellular Vesicles in Cancer Cell Migration and Metastasis

The infiltration of primary tumors and metastasis formation at distant sites strongly impact the prognosis and the quality of life of cancer patients. Current therapies including surgery, radiotherapy, and chemotherapy are limited in targeting the complex cell migration mechanisms responsible for cancer cell invasiveness and metastasis. A better understanding of these mechanisms and the development of new therapies are urgently needed. Extracellular vesicles (EVs) are lipid-enveloped particles involved in inter-tissue and inter-cell communication. This review article focuses on the impact of EVs released by tumor cells, specifically on cancer cell migration and metastasis. We first introduce cell migration processes and EV subtypes, and we give an overview of how tumor-derived EVs (TDEVs) may impact cancer cell migration. Then, we discuss ongoing EV-based cancer therapeutic approaches, including the inhibition of general EV-related mechanisms as well as the use of EVs for anti-cancer drug delivery, focusing on the harnessing of TDEVs. We propose a protein-EV shuttle as a route alternative to secretion or cell membrane binding, influencing downstream signaling and the final effect on target cells, with strong implications in tumorigenesis. Finally, we highlight the pitfalls and limitations of therapeutic EV exploitation that must be overcome to realize the promise of EVs for cancer therapy.

The cell senescence regulator p16 is a promising cancer prognostic and immune check-point inhibitor (ICI) therapy biomarker

Cyclin-dependent kinase inhibitor 2A (CDKN2A) encodes the cell senescence regulator protein p16. The expression of p16 raises in cell senescence and has a nuclear regulation in cell aging. Meanwhile, it's also reported to inhibit the aggression of several cancers. But its clinical application and role in cancer immunotherapy needs further investigation. We collected the transcriptional data of pan-cancer and normal human tissues from The Cancer Genome Atlas and the Genotype-Tissue Expression databases. CBioPortal webtool was employed to mine the genomic alteration status of CDKN2A across cancers. Kaplan-Meier method and univariate Cox regression were performed for prognostic assessments across cancers, respectively. Gene Set Enrichment Analysis is the main method used to search the associated cancer hallmarks associated with CDKN2A. TIMER2.0 was used to analyze the immune cell infiltration relevance with CDKN2A in pan-cancer. The associations between CDKN2A and immunotherapy biomarkers or regulators were performed by spearman correlation analysis. We found CDKN2A is overexpressed in most cancers and exhibits prognosis predictive ability in various cancers. In addition, it is significantly correlated with immune-activated hallmarks, cancer immune cell infiltrations and immunoregulators. The most interesting finding is that CDKN2A can significantly predict anti-PDL1 therapy response. Finally, specific inhibitors which correlated with CDKN2A expression in different cancer types were also screened by using Connectivity Map (CMap) tool. The results revealed that CDKN2A acts as a robust cancer prognostic and immunotherapy biomarker. Its function in the regulation of cancer cell senescence might shape the tumor microenvironment and contribute to its predictive ability of immunotherapy.

Recent advances of small extracellular vesicle biomarkers in breast cancer diagnosis and prognosis

Current clinical tools for breast cancer (BC) diagnosis are insufficient but liquid biopsy of different bodily fluids has recently emerged as a minimally invasive strategy that provides a real-time snapshot of tumour biomarkers for early diagnosis, active surveillance of progression, and post-treatment recurrence. Extracellular vesicles (EVs) are nano-sized membranous structures 50-1000 nm in diameter that are released by cells into biological fluids. EVs contain proteins, nucleic acids, and lipids which play pivotal roles in tumourigenesis and metastasis through cell-to-cell communication. Proteins and miRNAs from small EVs (sEV), which range in size from 50-150 nm, are being investigated as a potential source for novel BC biomarkers using mass spectrometry-based proteomics and next-generation sequencing. This review covers recent developments in sEV isolation and single sEV analysis technologies and summarises the sEV protein and miRNA biomarkers identified for BC diagnosis, prognosis, and chemoresistance. The limitations of current sEV biomarker research are discussed along with future perspective applications.

Improvement of the anticancer efficacy of PD-1/PD-L1 blockade via combination therapy and PD-L1 regulation

Immune checkpoint molecules are promising anticancer targets, among which therapeutic antibodies targeting the PD-1/PD-L1 pathway have been widely applied to cancer treatment in clinical practice and have great potential. However, this treatment is greatly limited by its low response rates in certain cancers, lack of known biomarkers, immune-related toxicity, innate and acquired drug resistance, etc. Overcoming these limitations would significantly expand the anticancer applications of PD-1/PD-L1 blockade and improve the response rate and survival time of cancer patients. In the present review, we first illustrate the biological mechanisms of the PD-1/PD-L1 immune checkpoints and their role in the healthy immune system as well as in the tumor microenvironment (TME). The PD-1/PD-L1 pathway inhibits the anticancer effect of T cells in the TME, which in turn regulates the expression levels of PD-1 and PD-L1 through multiple mechanisms. Several strategies have been proposed to solve the limitations of anti-PD-1/PD-L1 treatment, including combination therapy with other standard treatments, such as chemotherapy, radiotherapy, targeted therapy, anti-angiogenic therapy, other immunotherapies and even diet control. Downregulation of PD-L1 expression in the TME via pharmacological or gene regulation methods improves the efficacy of anti-PD-1/PD-L1 treatment. Surprisingly, recent preclinical studies have shown that upregulation of PD-L1 in the TME also improves the response and efficacy of immune checkpoint blockade. Immunotherapy is a promising anticancer strategy that provides novel insight into clinical applications. This review aims to guide the development of more effective and less toxic anti-PD-1/PD-L1 immunotherapies.

New Circulating Circular RNAs with Diagnostic and Prognostic Potential in Advanced Colorectal Cancer

Circular RNAs (circRNAs) are a group of special endogenous long non-coding RNAs which are highly stable in the circulation, and, thus, more suitable as new biomarkers of colorectal cancer (CRC). The aim of our study was to explore the plasma expression levels of four circRNAs: has_circ_0001445, hsa_circ_0003028, hsa_circ_0007915 and hsa_circ_0008717 in patients with CRC and to evaluate their associations with clinicopathological characteristics and the clinical outcome of the patients. CircRNAs were extracted from patients’ plasma obtained prior to chemotherapy. Their expression levels were measured by qPCR and calculated applying the 2^−ΔΔCt method. The levels of all four circRNAs were significantly increased in the plasma of CRC patients. At the optimal cut-off values hsa_circ_0001445 and hsa_circ_0007915 in plasma could significantly distinguish between patients with or without metastatic CRC with 92.56% sensitivity and 42.86% specificity, and with 86.07% sensitivity and 57.14% specificity, respectively. The mean overall survival (OS) of patients with high/intermediate expression of hsa_circ_0001445 was 30 months, significantly higher in comparison with the mean OS of the patients with low expression—20 months (log-rank test, p = 0.034). In multivariate Cox regression analysis, the low levels of hsa_circ_0001445 were also associated with shorter survival (HR = 1.59, 95% CI: 1.02–2.47, p = 0.040). A prognostic significance of hsa_circ_0001445 for patients with metastatic CRC was established.

Immune checkpoint blockade in the treatment of malignant tumor: current statue and future strategies

After being stagnant for decades, there has finally been a paradigm shift in the treatment of cancer with the emergence and application of immune checkpoint inhibitors (ICIs). The most extensively utilized ICIs are targeting the pathways involving programmed death-1 (PD-1) and cytotoxic T-lymphocyte associated protein 4 (CTLA-4). PD-1, as an crucial immune inhibitory molecule, by and large reasons the immune checkpoint response of T cells, making tumor cells get away from immune surveillance. Programmed cell death ligand-1 (PD-L1) is exceptionally expressed in most cancers cells and approves non-stop activation of the PD-1 pathway in the tumor microenvironment. PD-1/PD-L1 inhibitors can block the combination of PD-1 and PD-L1, inhibit hostile to regulatory signals, and restore the activity of T cells, thereby bettering immune response. The current researchers assume that the efficacy of these drugs is related to PD-L1 expression in tumor tissue, tumor mutation burden (TMB), and other emerging biomarkers. Although malignant tumors can benefit from the immunotherapy of PD-1/PD-L1 inhibitors, formulating a customized medication model and discovering biomarkers that can predict efficacy are the new trend in the new era of malignant tumor immunotherapy. This review summarizes the mechanism of action of PD-1/PD-L1 inhibitors, their clinical outcomes on various malignant tumors, their efficacy biomarkers, as well as predictive markers of irAEs.

Non-Coding RNAs: Emerging Therapeutic Targets in Spinal Cord Ischemia-Reperfusion Injury

Paralysis or paraplegia caused by transient or permanent spinal cord ischemia–reperfusion injury (SCIRI) remains one of the most devastating post-operative complications after thoracoabdominal aortic surgery, even though perioperative strategies and surgical techniques continue to improve. Uncovering the molecular and cellular pathophysiological processes in SCIRI has become a top priority. Recently, the expression, function, and mechanism of non-coding RNAs (ncRNAs) in various diseases have drawn wide attention. Non-coding RNAs contain a variety of biological functions but do not code for proteins. Previous studies have shown that ncRNAs play a critical role in SCIRI. However, the character of ncRNAs in attenuating SCIRI has not been systematically summarized. This review article will be the first time to assemble the knowledge of ncRNAs regulating apoptosis, inflammation, autophagy, and oxidative stress to attenuate SCIRI. A better understanding of the functional significance of ncRNAs following SCIRI could help us to identify novel therapeutic targets and develop potential therapeutic strategies. All the current research about the function of nRNAs in SCIRI will be summarized one by one in this review.

Exosomal long non-coding RNAs: Emerging players in cancer metastasis and potential diagnostic biomarkers for personalized oncology

Metastasis is a major challenge in the treatment of cancer. Exosomes are a class of small extracellular vesicles (EVs) that play critical roles in several human diseases, especially cancer, by transferring information (e.g., DNA, RNA, and protein) via cell-to-cell communication. Numerous recent studies have shown that exosomal long non-coding RNAs (lncRNAs) play crucial regulatory roles in cancer metastasis in the tumor microenvironment by altering the expression of several key signaling pathways and molecules. Due to their specificity and sensitivity, exosomal lncRNAs have potential as novel tumor markers and therapeutic targets in the treatment of cancer metastasis. In this review, we aim to summarize the roles of exosomal lncRNAs in cancer metastasis, the mechanisms underlying their roles, and their potential clinical applications.

Role of exosomal long non-coding RNAs in colorectal cancer

Exosomes are a class of small extracellular vesicles, 30-150 nm in diameter, that transfer biological information (e.g., DNA, RNA, and protein) via cell-to-cell communication. Exosomes play critical roles in the occurrence and development of human cancers, including colorectal cancer (CRC). Recent studies have shown that long non-coding RNAs (lncRNAs) can be encapsulated in exosomes, which transfer lncRNAs from secretory cells into recipient cells. This process affects the progression of CRC, since exosomal lncRNAs display special and extensive functions in CRC tumorigenesis, including malignant proliferation, metastasis, chemoresistance, and inflammatory response. Moreover, due to their specificity and sensitivity, exosomal lncRNAs are released into body fluids (e.g., urine, sputum, and plasma), which have the potential to be biomarkers of CRC tumorigenesis within screening efforts and medical and epidemiologic research. In this review, we aim to clarify the function and mechanism of exosomal lncRNAs in CRC tumorigenesis and provide a strategy for early diagnosis and medical treatment of this malignancy.

Correlation analysis of tumor mutation burden of hepatocellular carcinoma based on data mining

Background

The aim of this study was to determine the relationship between tumor mutation burden (TMB) and prognosis of patients with hepatocellular carcinoma (HCC), and to explore the differential expression of genes in HCC by TMB and the relationship between immune cells, TMB, and HCC.

Methods

Somatic variation data, gene transcriptional expression data and clinical information of patients with HCC were obtained from cancer genome map (TCGA) database. Analyze the characteristics of the gene mutation data of the sample, divide the high and low TMB groups and draw the survival curve at the same time, carry on the difference analysis to the gene of TMB, further carry on the univariate Cox regression analysis and Lasso regression analysis and construct the clinical model. Download the dataset GSE14520, from the Gene Expression Omnibus (GEO) database to verify the genes of the prognostic model. The differential genes were analyzed by gene ontology (GO) enrichment analysis and Kyoto encyclopedia of genes and genomes by (KEGG) enrichment analysis. Then the relative abundance of 22 immune cell types in HCC and normal control samples was calculated. Finally, the correlation between the scores of immune cells and Risk model was analyzed.

Results

Tumor protein p53 (TP53), catenin1 (CTNNB1), titin (TTN), mucin 16 (MUC16), and albumin (ALB) are the most common top 5 mutations in HCC. The prognosis of high level TMB group is worse than that of low TMB group. A total of 122 differentially expressed genes were screened by differential analysis of TMB genes. SQSTM1, ME1, BAMBI and PTTG1 are independent risk factors for poor prognosis of HCC. GO and KEGG analysis showed that the differential genes were mainly in extracellular matrix and immune response. There were significant differences in the distribution of Macrophages M0 and T cells CD4 native cells between HCC and normal tissues, which were correlated with the differential genes of TMB and correlated with prognosis.

Conclusions

There is a negative correlation between TMB and the prognosis of patients with HCC. TMB has an effect on the differential expression of genes in HCC cells and the distribution of immune cells in tumor tissues.

Downregulation of lncRNA RPLP0P2 inhibits cell proliferation, invasion and migration, and promotes apoptosis in colorectal cancer

Recent studies have revealed that long noncoding RNAs (lncRNAs) are closely associated with colorectal cancer (CRC); however, the role of the lncRNA RPLP0P2 in CRC remains largely unknown. In the present study, RNA expression profiles of CRC were collected from The Cancer Genome Atlas database and the prognosis of CRC with respect to RPLP0P2 was assessed. Subsequently, RPLP0P2 expression was knocked down in the human CRC cell line RKO using a short hairpin RNA (shRNA) lentivirus, and the biological behaviors of the cells, such as proliferation, migration, cell cycle progression and apoptosis, were examined. The results demonstrated that the expression levels of RPLP0P2 were higher in CRC tissue compared with those in normal tissue, and RPLP0P2 was associated with prognosis. RPLP0P2 knockdown significantly decreased cell colony formation, migration and invasion, and arrested CRC cells in the S phase to G₂/M phase transition. Furthermore, apoptosis was significantly increased in CRC cells infected with the RPLP0P2 shRNA lentivirus compared with in the control group. In conclusion, RPLP0P2 may promote proliferation, invasion and migration, and inhibit apoptosis of CRC cells, suggesting that RPLP0P2 may function as an oncogene in CRC.

Ocoxin as a complement to first line treatments in cancer

Chemotherapy and radiotherapy are the most frequent treatment for patients suffering from malignant progression of cancer. Even though new treatments are now being implemented, administration of these chemotherapeutic agents remains as the first line option in many tumor types. However, the secondary effects of these compounds represent one of the main reasons cancer patients lose life quality during disease progression. Recent data suggests that Ocoxin, a plant extract and natural compound based nutritional complement rich in antioxidants and anti-inflammatory mediators exerts a positive effect in patients receiving chemotherapy and radiotherapy. This mixture attenuates the chemotherapy and radiotherapy-related side effects such as radiation-induced skin burns and mucositis, chemotherapy-related diarrhea, hepatic toxicity and blood-infection. Moreover, it has been proven to be effective as anticancer agent in different tumor models both in vitro and in vivo, potentiating the cytotoxic effect of several chemotherapy compounds such as Lapatinib, Gemcitabine, Paclitaxel, Sorafenib and Irinotecan. The aim of this review is to put some light on the potential of this nutritional mixture as an anticancer agent and complement for the standard chemotherapy routine.

Extracellular Vesicles Regulate Cancer Metastasis

Metastatic cancer is a complex disease associated with poor prognosis and accounts for the majority of cancer related deaths. To date, many of the molecular mechanisms driving metastatic disease remain elusive and require further investigation for the development of effective treatment strategies. Recent studies have shown that extracellular vesicles (EVs) can be exploited by tumors to assist in cancer cell growth, proliferation, migration, invasion and metastasis. Cancer cells have proven efficient in educating fibroblasts, within their microenvironment, to secrete EVs as communicative vessels for mediating phenotypic changes in recipient cells. Using this vesicular delivery system, cancer cells can establish a new metastatic niche within distant sites, away from the primary tumor, thus favoring cancer progression. These findings demonstrate the availability of a new route for therapeutic intervention in the inhibition of cancer dissemination. Although, several approaches to target cancer cell secretion of EVs are detailed in the literature, there is still no defined way to currently apply them in clinical settings. Hence, further studies are required to unravel the molecular mechanisms of metastasis - governed by the establishment and release of cancer associated EVs.

Protective effect of bone marrow mesenchymal stem cell-derived exosomes against the reproductive toxicity of cyclophosphamide is associated with the p38MAPK/ERK and AKT signaling pathways

Spermatogenic dysfunction caused by cyclophosphamide (CP) chemotherapy has seriously influenced the life quality of patients. Unfortunately, treatments for CP-induced testicular spermatogenic dysfunction are limited, and the molecular mechanisms are not fully understood. For the first time, here, we explored the effects of bone marrow mesenchymal stem cell-derived exosomes (BMSC-exos) on CP-induced testicular spermatogenic dysfunction in vitro and in vivo. BMSC-exos could be taken up by spermatogonia (GC1-spg cells). CP-injured GC1-spg cells and BMSC-exos were cocultured at various doses, and then, cell proliferation was measured using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay. In addition, photophosphorylation of extracellular-regulated kinase (ERK), p38 mitogen-activated protein kinase (p38MAPK), and protein kinase B (AKT) proteins was evaluated by western blotting as well as apoptosis in GC1-spg cells measured using flow cytometry. Treatment with BMSC-exos enhanced cell proliferation and reduced apoptosis of CP-injured GCI-spg cells. Phosphorylated levels of ERK, AKT, and p38MAPK proteins were reduced in CP-injured spermatogonia when co-treated with BMSC-exos, indicating that BMSC-exos acted against the reproductive toxicity of CP via the p38MAPK/ERK and AKT signaling pathways. In experiments in vivo, CP-treated rats received BMSC-exos by injection into the tail vein, and testis morphology was compared between treated and control groups. Histology showed that transfusion of BMSC-exos inhibited the pathological changes in CP-injured testes. Thus, BMSC-exos could counteract the reproductive toxicity of CP via the p38MAPK/ERK and AKT signaling pathways. The findings provide a potential treatment for CP-induced male spermatogenic dysfunction using BMSC-exos.

Exosomal noncoding RNAs in cholangiocarcinoma: Laboratory noise or hope?

Currently, extracellular vesicles and particularly exosomes have gained a lot of research interest due to their unique roles in several biological processes. Noncoding RNAs (microRNAs, long noncoding RNAs and circular RNAs) represent a class of functional RNA with distinct regulatory roles in tumorigenesis and cancer progression. Cholangiocarcinoma is a rare but highly aggressive type of malignancy that is very challenging to diagnose, especially in early stages; surgical resection still represents the sole potentially curative treatment option. Hence, there is an urgent need for the discovery of novel diagnostic and prognostic biomarkers. Hereby, we provide a comprehensive review of the most recent discoveries that focus on exosomal noncoding RNAs in cholangio-carcinoma with the aim to identify new molecular players that could be used as biomarkers and therapeutic targets.

Small extracellular vesicles (sEVs): discovery, functions, applications, detection methods and various engineered forms

INTRODUCTION

Extracellular vesicles (EVs) are cell-created delivery systems of proteins, lipids, or nucleic acids, and means of extracellular communication. Though sEVs were initially considered to be the waste disposal mechanism, today they are at the forefront of research with different biological and pathological functions. Such EVs play a key role in the immunoregulation, CNS development, nervous system physiology, mammary gland development, induction of immunosuppression in pregnancy, the developmental signaling pathways, regeneration of different tissues, inflammation, angiogenesis, coagulation, apoptosis, stem cell differentiation, and extracellular matrix turnover.

AREAS COVERED

SEVs contribute to the pathogenesis of different cancers and the progression of various neurodegenerative diseases, infections, as well as metabolic and cardiovascular diseases. Expert Opinion: There is no exact classification for EVs; however, according to size, density, morphological features, content, and biogenesis, they can be categorized into three major classes: microvesicles (ectosomes or microparticles), apoptotic bodies, and sEVs. SEVs, as an important class of EVs, have a crucial role in distinct biological functions. Moreover, shedding light on different structural and molecular aspects of sEV has led to their application in various therapeutic, diagnostic, and drug delivery fields. In this review, we have endeavored to elaborate on different aspects of EVs, especially sEVs.

Upregulation of long non-coding RNA LOC284454 may serve as a new serum diagnostic biomarker for head and neck cancers

Background

Identification of effective diagnostic and prognostic biomarkers of cancer is necessary for improving precision medicine. Long non-coding RNAs (lncRNAs) play an important regulatory role in tumor initiation and progression. The lncRNA LOC284454 is distinctly expressed in various head and neck cancers (HNCs), as demonstrated by our previous bioinformatics analysis. However, the expression levels and functions of LOC284454 in cancer are still unclear.

Methods

We investigated the dysregulation of lncRNAs in HNCs using the GEO database and found that LOC284454 was highly expressed in HNCs. Serum samples from 212 patients with HNCs and 121 normal controls were included in this biomarker study. We measured the expression of LOC284454 in the sera of HNC patients and normal controls using RT-qPCR. Receiver operating characteristics (ROC) analysis is an important statistical method that is widely used in clinical diagnosis and disease screening. ROC was used to analyze the clinical value of LOC284454 in the early diagnosis of HNCs.

Results

LOC284454 was significantly upregulated in the sera of patients with nasopharyngeal carcinoma, oral cancer, and thyroid cancer. LOC284454 upregulation had good clinical diagnostic value in these cancers, as evaluated by area under the ROC curve values of 0.931, 0.698, and 0.834, respectively.

Conclusions

LOC284454 may be a valuable serum biomarker for HNCs facilitating the early diagnosis of malignant cancers. Further studies are needed to elucidate the mechanisms underlying the involvement of LOC284454 in HNCs. This study provides the first evidence that LOC284454 may be a serum biomarker for HNCs.

Non-coding RNAS and colorectal cancer liver metastasis

More than 50% of colorectal cancer (CRC) deaths are attributed to metastasis, and the liver is the most common distant metastatic site of CRC. The molecular mechanisms underlying CRC liver metastasis are very complicated and remain largely unknown. Accumulated evidence has shown that non-coding RNAs (NcRNAs) play critical roles in tumor development and progression. Here we reviewed the roles and underlying mechanisms of NcRNAs in CRC liver metastasis.

Extracellular vesicle-mediated crosstalk between melanoma and the immune system: Impact on tumor progression and therapy response

Melanoma is a very lethal tumor type that easily spreads and colonizes regional and distant tissues. Crucial phenotypic changes that favor melanoma metastasis are interposed by the tumor microenvironment (TME), representing a complex network in which malignant cells communicate not only with each other but also with stromal and immune cells. This cell-cell communication can be mediated by extracellular vesicles (EVs), which are lipid bilayer-delimited particles capable of carrying a wide variety of bioactive compounds. Both melanoma-derived or TME-derived EVs deliver important pro- and antitumor signals implicated in various stages of tumor progression, such as proliferation, metastasis, and treatment response. In this review, we highlight the recent advances in EV-mediated crosstalk between melanoma and immune cells and other important cells of the TME, and address different aspects of this bidirectional interaction as well as how this may hinder or trigger the development and progression of melanoma. We also discuss the potential of using EVs as biomarkers and therapeutic strategies for melanoma.

Extracellular Vesicles in Oral Squamous Cell Carcinoma and Oral Potentially Malignant Disorders: A Systematic Review

Extracellular vesicles (EVs) are secreted from most cell types and utilized in a complex network of near and distant cell-to-cell communication. Insight into this complex nanoscopic interaction in the development, progression and treatment of oral squamous cell carcinoma (OSCC) and precancerous oral mucosal disorders, termed oral potentially malignant disorders (OPMDs), remains of interest. In this review, we comprehensively present the current state of knowledge of EVs in OSCC and OPMDs. A systematic literature search strategy was developed and updated to December 17, 2019. Fifty-five articles were identified addressing EVs in OSCC and OPMDs with all but two articles published from 2015, highlighting the novelty of this research area. Themes included the impact of OSCC-derived EVs on phenotypic changes, lymph-angiogenesis, stromal immune response, mechanisms of therapeutic resistance as well as utility of EVs for drug delivery in OSCC and OPMD. Interest and progress of knowledge of EVs in OSCC and OPMD has been expanding on several fronts. The oral cavity presents a unique and accessible microenvironment for nanoparticle study that could present important models for other solid tumours.

Exosome-mediated transfer of long noncoding RNA H19 induces doxorubicin resistance in breast cancer

Development of the acquired resistance is one major obstacle during chemotherapy for cancer patients. Exosomes mediate intercellular communication and cause environmental changes in tumor progression by transmitting active molecules. In this study, the role of long noncoding RNA H19 within exosomes is elucidated in terms of regulating doxorubicin (DOX) resistance of breast cancer. As a result, increased H19 expression was observed in DOX-resistant breast cancer cells in comparison with the corresponding parental cells. Suppression of H19 significantly lowered DOX resistance by decreasing cell viability, lowering colony-forming ability, and inducing apoptosis. Moreover, extracellular H19 could be moved to sensitive cells via being incorporated into exosomes. Treating sensitive cells with exosomes from resistant cells increased the chemoresistance of DOX, while downregulation of H19 in sensitive cells abated this effect. Taken together, H19 could be delivered by exosomes to sensitive cells, leading to the dissemination of DOX resistance. Our finding highlights the potential of exosomal H19 as a molecular target to reduce DOX resistance.

Exosomes in Bone Sarcomas: Key Players in Metastasis

Bone sarcomas are rare cancers which often present with metastatic disease and are still associated with poor survival rates. Studies in the last decade have identified that exosomes, a type of extracellular vesicle released by cells, play an important role in tumour progression and dissemination. Through the transfer of their cargo (RNAs, proteins, and lipids) across cells, they are involved in cellular cross-talk and can induce changes in cellular behaviour. Exosomes have been shown to be important in metastasis organotropism, induction of angiogenesis and vascular permeability, the education of cells towards a pro-metastatic phenotype or the interaction between stromal and tumour cells. Due to the importance exosomes have in disease progression and the high incidence of metastasis in bone sarcomas, recent studies have evaluated the implications of these extracellular vesicles in bone sarcomas. In this review, we discuss the studies that evaluate the role of exosomes in osteosarcoma, Ewing sarcoma, and preliminary data on chondrosarcoma.

Propofol and Sevoflurane Differentially Impact MicroRNAs in Circulating Extracellular Vesicles during Colorectal Cancer Resection

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Background

Extracellular vesicles and their microRNA cargo are crucial facilitators of malignant cell communication and could mediate effects of anesthetics on tumor biology during cancer resection. The authors performed a proof-of-concept study to demonstrate that propofol and sevoflurane have differential effects on vesicle-associated microRNAs that influence signaling pathways involved in tumor progression and metastasis.

Methods

Circulating vesicles were investigated in a prospective, matched-case pilot study in two cohorts of colorectal cancer patients receiving either propofol (n = 8) or sevoflurane (n = 9), matched for tumor stage and location. Serum was sampled before anesthesia and after tumor resection. Vesicular microRNA profiles were analyzed by next generation sequencing and confirmed by real-time polymerase chain reaction. Next, we assessed perioperative changes in microRNA expression induced by either anesthetic and compared their biologic effects on tumor-relevant pathways. Additionally, vesicles from pre- and postoperative sera were biologic characterized.

Results

Postoperative microRNA profiles were shifted in both groups with overlap in the perioperative response. A total of 64 (48 up, range of log2 fold change 1.07 to 3.76; 16 down, −1.00 to −1.55) and 33 (32 up, 1.02 to 2.98; 1 down, −1.36) microRNAs were significantly regulated (adjusted P value less than 0.05) by propofol and sevoflurane, respectively. Thirty-six (propofol) and five (sevoflurane) microRNAs were specifically responsive to either anesthetic agent. In silico target analyses of microRNA expression patterns indicated an inhibitory effect of propofol on crucial carcinoma-related pathways such as proliferation (z-score, −1.73) and migration (z-score, −1.97), as well as enhanced apoptosis (z-score, 1.19). While size distribution and protein markers of circulating vesicles were not affected by anesthesia, their concentration was reduced after surgery using both anesthetic procedures.

Conclusions

This proof-of-concept study provides preliminary evidence that anesthetic agents have specific effects on microRNA profiles in circulating vesicles. These findings could form the basis for larger and mechanistically oriented outcome studies in cancer patients.

Long non-coding RNA LOC284454 promotes migration and invasion of nasopharyngeal carcinoma via modulating the Rho/Rac signaling pathway

Nasopharyngeal carcinoma (NPC) is a unique malignant cancer with high metastasis. Because the early symptoms of NPC patients are not obvious, most patients have distant metastases when diagnosed, which makes treatment difficult. Long non-coding RNAs (lncRNAs) are emerging as important regulators in human carcinogenesis. LncRNAs have been increasingly identified but remain largely unknown in NPC. Therefore, we performed gene expression profiling to screen for altered expression of lncRNAs in NPC tissues and adjacent samples. One lncRNA, LOC284454, was upregulated and associated with poor prognosis in NPC. In in vivo and in vitro assays, LOC284454 promoted the migration and invasion capacity of NPC cells. Mass spectrometry combined with bioinformatics suggested that LOC284454 affected the cytoskeletal and adhesion-related Rho/Rac signaling pathways. LOC284454 may be a potential novel treatment target and is expected to be a new diagnostic and prognostic marker in patients with NPC.

Specific trophoblast transcripts transferred by extracellular vesicles affect gene expression in endometrial epithelial cells and may have a role in embryo-maternal crosstalk

Background

Successful establishment of pregnancy hinges on appropriate communication between the embryo and the uterus prior to implantation, but the nature of this communication remains poorly understood. Here, we tested the hypothesis that the endometrium is receptive to embryo-derived signals in the form of RNA.

Methods

We have utilized a non-contact co culture system to simulate the conditions of pre implantation environment of the uterus. We bioorthogonally tagged embryonic RNA and tracked the transferred transcripts to endometrium. Transferred transcripts were separated from endometrial transcripts and sequenced. Changes in endometrial transcripts were quantified using quantitative PCR.

Results

We show that three specific transcripts are transferred to endometrial cells. We subsequently demonstrate a role of extracellular vesicles (EVs) in this process, as EVs obtained from cultured trophoblast spheroids incubated with endometrial cells induced down-regulation of all the three identified transcripts in endometrial cells.

Finally, we show that EVs/nanoparticles captured from conditioned culture media of viable embryos as opposed to degenerating embryos induce ZNF81 down-regulation in endometrial cells, hinting at the functional importance of this intercellular communication.

Conclusion

Ultimately, our findings demonstrate the existence of an RNA-based communication which may be of critical importance for the establishment of pregnancy.

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.

The survival analysis and oncogenic effects of CFP1 and 14-3-3 expression on gastric cancer

Background & aim

Gastric cancer (GC) is the third-leading cause of cancer-related deaths. We established a prospective database of patients with GC who underwent surgical treatment. In this study, we explored the prognostic significance of the expression of CFP1 and 14-3-3 in gastric cancer, by studying the specimens collected from clinical subjects.

Materials & methods

Immunohistochemistry was used to detect the expression of CFP1 and 14-3-3 in 84 GC subjects, including 73 patients who have undergone radical gastrectomy and 11 patients who have not undergone radical surgery. Survival analysis was performed by km-plot data.

Results

According to the survival analysis, we can see that the survival time of patients with high expression of CFP1 is lower than the patients with low expression in gastric cancer, while the effect of 14-3-3 is just the opposite. The survival time of patients with higher expression of 14-3-3 is also longer.

Conclusion

The CFP1 and 14-3-3 genes can be used as prognostic markers in patients with GC, but the study is still needed to confirm.

GPC6 Promotes Cell Proliferation, Migration, and Invasion in Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a highly metastatic tumor that occurs frequently in Southeast Asia, particularly including southern China. Epstein-Barr virus infection is well established as a primary cause of NPC; nevertheless, the mechanisms underlying NPC pathogenesis remain largely unknown. In our previous study, we conducted whole-genome sequencing to screen for genomic variations that were associated with NPC. Of the resultantly identified variations, glypican-6 (GPC6), was shown, for the first time, to be frequently mutated in NPC. In the present study, we verified this finding and conducted a series of functional experiments, which demonstrated that GPC6 promotes the migration, invasion, and proliferation of NPC cells in vitro. Thus, the present study identified novel biological functions for GPC6 in NPC, and thus, showed that GPC6 may be a promising potential therapeutic target for this disease.

circMAN1A2 could serve as a novel serum biomarker for malignant tumors

Novel diagnostic and prognostic biomarkers of cancers are needed to improve precision medicine. Circular RNAs act as important regulators in cancers at the transcriptional and posttranscriptional levels. The circular RNA circMAN1A2 is highly expressed in nasopharyngeal carcinoma according to our previous RNA sequencing data; however, the expression and functions of circMAN1A2 in cancers are still obscure. Therefore, in this study, we evaluated the expression of circMAN1A2 in the sera of patients with nasopharyngeal carcinoma and other malignant tumors and analyzed its correlations with clinical features and diagnostic values. The expression levels of circMAN1A2 were detected by quantitative real-time PCR, and the correlations of clinical features with circMAN1A2 expression were analyzed by χ² tests. Receiver operating characteristic curves were used to evaluate the clinical applications of circMAN1A2. The results showed that circMAN1A2 was upregulated in nasopharyngeal carcinoma, oral cancer, thyroid cancer, ovarian cancer, and lung cancer, with areas under the curves of 0.911, 0.779, 0.734, 0.694, and 0.645, respectively, indicating the good diagnostic value of circMAN1A2. Overall, our findings suggested that circMAN1A2 could be a serum biomarker for malignant tumors, providing important insights into diagnostic approaches for malignant tumors. Further studies are needed to elucidate the mechanisms of circMAN1A2 in the pathogenesis of cancer.

Proteomic Analysis of the Molecular Mechanism of Lovastatin Inhibiting the Growth of Nasopharyngeal Carcinoma Cells

Metabolic abnormalities are one of the essential features of tumors. Increasingly more studies have shown that lovastatin, a lipid-reducing drug, has visible inhibitory effects on tumors, but it has not been reported in nasopharyngeal carcinoma. In this paper, we explored the effects of lovastatin on the growth of nasopharyngeal carcinoma cells and its possible molecular mechanisms. After treating nasopharyngeal carcinoma cells with different concentrations of lovastatin, we found that lovastatin can inhibit the growth of nasopharyngeal carcinoma in a time- and dose-dependent manner. To explore the molecular mechanism of how lovastatin inhibits the growth of nasopharyngeal carcinoma, we examined the proteome of nasopharyngeal carcinoma cells treated at different time points using an LC/MS whole-proteomic strategy. The molecular network of differentially expressed proteins was constructed using IPA software. It was found that lovastatin inhibited the growth of nasopharyngeal carcinoma cells mainly by affecting the EIF2 and the mTOR pathways, which regulate cell metabolism and apoptosis. The results of this study provide a robust basis for further research on the molecular mechanism of lovastatin's inhibition of nasopharyngeal carcinoma cells and provide a reference for the clinical use of lovastatin in the treatment of nasopharyngeal carcinoma.

Herpesvirus acts with the cytoskeleton and promotes cancer progression

The cytoskeleton is a complex fibrous reticular structure composed of microfilaments, microtubules and intermediate filaments. These components coordinate morphology support and intracellular transport that is involved in a variety of cell activities, such as cell proliferation, migration and differentiation. In addition, the cytoskeleton also plays an important role in viral infection. During an infection by a Herpesvirus, the virus utilizes microfilaments to enter cells and travel to the nucleus by microtubules; the viral DNA replicates with the help of host microfilaments; and the virus particles start assembling with a capsid in the cytoplasm before egress. The cytoskeleton changes in cells infected with Herpesvirus are made to either counteract or obey the virus, thereby promote cell transforming into cancerous ones. This article aims to clarify the interaction between the virus and cytoskeleton components in the process of Herpesvirus infection and the molecular motor, cytoskeleton-associated proteins and drugs that play an important role in the process of a Herpesvirus infection and carcinogenesis process.

Exosomes: from carcinogenesis and metastasis to diagnosis and treatment of gastric cancer

Exosomes represent an important group of extracellular vesicles with a defined size between 40 and 150 nm and cup-shaped construction which have a pivotal role in elimination of intracellular debris and intercellular signaling networks. A line of evidence revealed the impact of different types of exosomes in initiation, progression, and metastasis of gastric cancer (GC). These bioactive vesicles mediate tumor and stromal communication network through modulation of cell signaling for carcinogenesis and pre-metastatic niche formation in distant organs. Exosomes contain various cargos including DNAs (mitochondrial and genomic), proteins, transposable elements, and RNAs (coding and noncoding) with different compositions related to functional status of origin cells. In this review, we summarize the main roles of key exosomal cargos in induction of exosome-mediated signaling in cancer cells. Body fluids are employed frequently as the source of exosomes released by tumor cells with a potential role in early diagnosis of GC and chemoresistance. These vesicles as non-toxic and non-immunogenic carriers are also found to be applied for novel drug delivery systems.

A network-based approach to identify DNA methylation and its involved molecular pathways in testicular germ cell tumors

Background: Testicular germ cell tumors (TGCT) is the most common testicular malignancy threaten young male reproductive health. This study aimed to identify aberrantly methylated-differentially expressed genes and pathways in TGCT by comprehensive bioinformatics analysis.

Methods: Data of gene expression microarrays (GSE3218, GSE18155) and gene methylation microarrays (GSE72444) were collected from GEO database. Integrated analysis acquired aberrantly methylated-genes. Functional and pathway enrichment analysis were performed using DAVID database. Protein-protein interaction (PPI) network was constructed by STRING and App Mcode was used for module analysis. GEPIA platform and DiseaseMeth database were used for confirming the expression and methylation levels of hub genes. Finally, Human Protein Atlas database was performed to evaluate the prognostic significance.

Results: Totally 604 hypomethylation-high expression and 147 hypermethylation-low genes were identified. The high expressed genes were enriched in biological processes of cell proliferation and migration. The top 8 hub genes of PPI network were GAPDH, VEGFA, PTPRC, RIPK4, MMP9, CSF1R, KRAS and FN1. After validation in GEPIA platform, all hub genes were elevated in TGCT tissues. Only MMP9, CSF1R and PTPRC showed hypomethylation-high expression status, which predicted the poor outcome of TGCT patients.

Conclusion: Our study indicated possible aberrantly methylated-differentially expressed genes and pathways in TGCT by bioinformatics analysis, which may provide novel insights for unraveling pathogenesis of TGCT.

Cloning and characterization of the putative AFAP1-AS1 promoter region

Actin filament-associated protein 1-antisense RNA1 (AFAP1-AS1), a cancer-related long non-coding RNA, has been found to be upregulated in multiple types of cancers. AFAP1-AS1 is important for the initiation, progression and poor prognosis of many cancers, including nasopharyngeal carcinoma (NPC). However, the mechanism underlying the regulation of AFAP1-AS1 expression is not well-understood. In our study, the potential promoter region of AFAP1-AS1 was predicted by comprehensive bioinformatics analysis. Moreover, promoter deletion analysis identified the sequence between positions -359 and -28 bp as the minimal promoter region of AFAP1-AS1. The ChIP assay results indicate that the AFAP1-AS1 promoter is responsive to the transcription factor c-Myc, which can promote high AFAP1-AS1 expression. This study is the first to clone and characterize the AFAP1-AS1 promoter region. Our findings will help to better understand the underlying mechanism of high AFAP1-AS1 expression in tumorigenesis and to develop new strategies for therapeutic high expression of AFAP1-AS1 in NPC.

Role of the tumor microenvironment in PD-L1/PD-1-mediated tumor immune escape

Tumor immune escape is an important strategy of tumor survival. There are many mechanisms of tumor immune escape, including immunosuppression, which has become a research hotspot in recent years. The programmed death ligand-1/programmed death-1 (PD-L1/PD-1) signaling pathway is an important component of tumor immunosuppression, which can inhibit the activation of T lymphocytes and enhance the immune tolerance of tumor cells, thereby achieving tumor immune escape. Therefore, targeting the PD-L1/PD-1 pathway is an attractive strategy for cancer treatment; however, the therapeutic effectiveness of PD-L1/PD-1 remains poor. This situation requires gaining a deeper understanding of the complex and varied molecular mechanisms and factors driving the expression and activation of the PD-L1/PD-1 signaling pathway. In this review, we summarize the regulation mechanisms of the PD-L1/PD-1 signaling pathway in the tumor microenvironment and their roles in mediating tumor escape. Overall, the evidence accumulated to date suggests that induction of PD-L1 by inflammatory factors in the tumor microenvironment may be one of the most important factors affecting the therapeutic efficiency of PD-L1/PD-1 blocking.

Application of atomic force microscopy in cancer research

Atomic force microscopy (AFM) allows for nanometer-scale investigation of cells and molecules. Recent advances have enabled its application in cancer research and diagnosis. The physicochemical properties of live cells undergo changes when their physiological conditions are altered. These physicochemical properties can therefore reflect complex physiological processes occurring in cells. When cells are in the process of carcinogenesis and stimulated by external stimuli, their morphology, elasticity, and adhesion properties may change. AFM can perform surface imaging and ultrastructural observation of live cells with atomic resolution under near-physiological conditions, collecting force spectroscopy information which allows for the study of the mechanical properties of cells. For this reason, AFM has potential to be used as a tool for high resolution research into the ultrastructure and mechanical properties of tumor cells. This review describes the working principle, working mode, and technical points of atomic force microscopy, and reviews the applications and prospects of atomic force microscopy in cancer research.

Effects of tumor metabolic microenvironment on regulatory T cells

Recent studies have shown that on one hand, tumors need to obtain a sufficient energy supply, and on the other hand they must evade the body’s immune surveillance. Because of their metabolic reprogramming characteristics, tumors can modify the physicochemical properties of the microenvironment, which in turn affects the biological characteristics of the cells infiltrating them. Regulatory T cells (Tregs) are a subset of T cells that regulate immune responses in the body. They exist in large quantities in the tumor microenvironment and exert immunosuppressive effects. The main effect of tumor microenvironment on Tregs is to promote their differentiation, proliferation, secretion of immunosuppressive factors, and chemotactic recruitment to play a role in immunosuppression in tumor tissues. This review focuses on cell metabolism reprogramming and the most significant features of the tumor microenvironment relative to the functional effects on Tregs, highlighting our understanding of the mechanisms of tumor immune evasion and providing new directions for tumor immunotherapy.

High Expression of lncRNA AFAP1-AS1 Promotes the Progression of Colon Cancer and Predicts Poor Prognosis

Long non-coding RNAs (lncRNAs) are dysregulated in various cancers. However, the clinical relevance and functional roles of AFAP1-AS1 in colon cancer (CC) have not been clarified. We analyzed the lncRNA expression patterns in Gene Expression Omnibus (GEO) datasets and the Cancer Genome Atlas (TCGA) RNA-seq datasets, and found that the expression level of AFAP1-AS1 was significantly elevated in CC tissues. High levels of AFAP1-AS1 were associated with poor disease-free survival and overall survival in CC patients. In vitro experiments demonstrated that AFAP1-AS1 knockdown significantly inhibited the cell invasive and migration capability in CC cell line HT-29. AFAP1-AS1 knockdown also increased the expression of E-cadherin and ZO-1 while inhibited the expression of Vimentin, MMP9, ZEB1 and β-catenin, suggesting that AFAP1-AS1 is involved in the epithelial-mesenchymal transition (EMT) process of CC. Further studies confirmed that AFAP1-AS1 knockdown also affected the actin-cytokeratin signaling pathway. Thus, AFAP1-AS1 might be a potential novel diagnostic marker and therapeutic target for CC.

Long noncoding RNA AFAP1-AS1 acts as a competing endogenous RNA of miR-423-5p to facilitate nasopharyngeal carcinoma metastasis through regulating the Rho/Rac pathway

BACKGROUND

Actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1), a long noncoding RNA, is significantly highly expressed and associated with metastasis and poor prognosis in many cancers, including nasopharyngeal carcinoma (NPC). In this study, we aim to identify the role of AFAP1-AS1 acting as an oncogenic lncRNA to promote NPC metastasis.

METHODS

The role of AFAP1-AS1, miR-423-5p, and FOSL2 in NPC metastasis was investigated in vitro and in vivo. Bioinformatics analysis and luciferase activity assays were used to identify the interaction between AFAP1-AS1, miR-423-5p, and FOSL2. Additionally, real-time PCR and western blotting were used to assess the function of AFAP1-AS1 acting as an oncogenic lncRNA to promote NPC progression by regulating miR-423-5p and the downstream Rho/Rac pathway.

RESULTS

In this study, we determined that AFAP1-AS1 functions as a competing endogenous RNA in NPC to regulate the Rho/Rac pathway through miR-423-5p. These interactions can mediate the expression of RAB11B, LASP1, and FOSL2 and accelerate cell migration and invasion via the Rho/Rac signaling pathway or FOSL2. AFAP1-AS1 and FOSL2 could competitively bind with miR-423-5p to regulate several molecules, including RAB11B and LASP1 of the Rho/Rac signaling pathway. AFAP1-AS1 can also regulate the expression of LASP1, which was transcriptionally regulated by FOSL2, resulting in increased migration and invasion of NPC cells via the Rho/Rac signaling pathway.

CONCLUSIONS

The observations in this study identify an important role for AFAP1-AS1 as a competing endogenous RNA (ceRNA) in NPC pathogenesis and indicate that it may serve as a potential target for cancer diagnosis and treatment.

The emerging role of Epstein-Barr virus encoded microRNAs in nasopharyngeal carcinoma

Epstein-Barr virus (EBV) is an oncogenic herpes virus that is closely associated with the initiation and development of nasopharyngeal carcinoma (NPC), lymphoma and other malignant tumors. EBV encodes 44 mature miRNAs that regulate viral and host cell gene expression and plays a variety of roles in biological functions and the development of cancer. In this review, we summarized the biological functions and molecular mechanisms of Epstein-Barr virus-encoded microRNAs (EBV miRNAs) in tumor immune evasion, proliferation, anti-apoptosis, invasion, metastasis and as a potential biomarker for NPC diagnosis and prognosis. The knowledge generated by EBV miRNAs can be used for EBV miRNA-based precision cancer treatments in the near future.

Long non-coding RNA PVT1 predicts poor prognosis and induces radioresistance by regulating DNA repair and cell apoptosis in nasopharyngeal carcinoma

The long non-coding RNA, plasmacytoma variant translocation 1 (PVT1), is highly expressed in a variety of tumors, and is believed to be a potential oncogene. However, the role and mechanism of action of PVT1 in the carcinogenesis and progression of nasopharyngeal carcinomas (NPCs) remains unclear. In this study, for the first time, we have discovered that PVT1 shows higher expression in NPCs than in normal nasopharyngeal epithelial tissue, and patients with NPCs who show higher expression of PVT1 have worse progression-free and overall survivals. Additionally, we observed that the proliferation of NPC cells decreased, and their rate of apoptosis increased; these results indicated that the knockdown of PVT1 expression in the NPC cells induced radiosensitivity. Further, we have shown that the knockdown of PVT1 expression can induce apoptosis in the NPC cells by influencing the DNA damage repair pathway after radiotherapy. In general, our study shows that PVT1 may be a novel biomarker for prognosis and a new target for the treatment of NPCs. Additionally, targeting PVT1 may be a potential strategy for the clinical management of NPC and for the improvement of the curative effect of radiation in NPCs.