Identification of potential plasma biomarkers in early-stage nasopharyngeal carcinoma-derived exosomes based on RNA sequencing

CircNTRK2 promotes the progression of nasopharyngeal carcinoma via sponging miR-384 to regulate SOX4 expression

Circular RNAs (circRNAs) have been reported to function critical roles in the pathogenesis and progression of nasopharyngeal carcinoma (NPC). The role of circNTRK2 (circbase ID: hsa_circ_0139142) remains dimness in this disease. This study aimed to investigate the effects and underlying mechanism of circNTRK2 in NPC. GSE143797 was downloaded from the Gene Expression Omnibus (GEO) database, and differently expressed circRNAs were analyzed by the GEO2R method. CircNTRK2 expression was confirmed in human NPC tumor tissues and cell lines by real-time PCR. Loss-of-function studies were used to explore the influence of circNTRK2 on the proliferation, invasion, apoptosis, and epithelial-mesenchymal transition (EMT) of NPC cells. Then, bioinformatic analysis, luciferase reporter assay, biotinylated miRNA pull-down assay, real-time PCR, and Western blotting were applied to clarify the detailed mechanism. We found that circNTRK2 was highly expressed in NPC tissues and cells. Silencing of circNTRK2 inhibited proliferation, invasion and EMT, but facilitated apoptosis of NPC cells in vitro. Also, downregulation of circNTRK2 suppressed tumor growth in a xenograft mouse model. CircNTRK2 directly targeted and negatively mediated miR-384 expression. SOX4 was a target gene of miR-384 in NPC. Both miR-384 inhibitor and SOX4 upregulation could reverse the effects of circNTRK2 knockdown on the proliferation, invasion, EMT, and apoptosis of NPC cells. Whereas miR-384 mimics and SOX4 knockdown abrogated the influences of circNTRK2 upregulation on NPC cells. In conclusion, circNTRK2 promoted NPC progression via sponging miR-384 and inhibiting miR-384 activity, leading to the upregulation of SOX4. This study indicated that circNTRK2 might be a potential target for the treatment of NPC.

Exosomes: innovative biomarkers leading the charge in non-invasive cancer diagnostics

Exosomes, nanoscale extracellular vesicles secreted by diverse cell types, have emerged as promising biomarkers for non-invasive tumor diagnostics, offering significant advantages over traditional methods. These vesicles, typically ranging from 30 to 150 nanometers in size, carry a diverse cargo of proteins, lipids, RNA, and microRNAs, which reflect the molecular alterations occurring within their parent cells. Notably, exosomes can be isolated from easily accessible biofluids such as blood, urine, and saliva, making them ideal candidates for liquid biopsy applications. This review explores the transformative potential of exosome-based biomarkers in the early detection and monitoring of cancers across diverse organ systems, including respiratory, digestive, hematological, neurological, endocrine malignancies and so on. Special emphasis is placed on their application in clinical trials, where exosome-based diagnostics have demonstrated promising results in detecting tumors at early stages and monitoring treatment responses, offering a less invasive and more accessible alternative to traditional biopsies. While recent advancements in exosome isolation and characterization technologies have significantly improved the sensitivity and specificity of these diagnostics, challenges such as biological heterogeneity, lack of standardization, and regulatory hurdles remain. Nevertheless, exosome-based diagnostics hold the promise of providing real-time, dynamic insights into tumor progression, enhancing personalized medicine. The integration of exosomes into clinical practice could revolutionize cancer diagnostics and therapy, improving patient outcomes. Further research and large-scale clinical validation are essential to fully realize the clinical potential of exosome-based biomarker applications in routine clinical settings.

Unfolding the Complexity of Exosome-Cellular Interactions on Tumour Immunity and Their Clinical Prospects in Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy situated in the posterolateral nasopharynx. NPC poses grave concerns in Southeast Asia due to its late diagnosis. Together with resistance to standard treatment combining chemo- and radiotherapy, NPC presents high metastatic rates and common recurrence. Despite advancements in immune-checkpoint inhibitors (ICIs) and cytotoxic-T-lymphocytes (CTLs)-based cellular therapy, the exhaustive T cell profile and other signs of immunosuppression within the NPC tumour microenvironment (TME) remain as concerns to immunotherapy response. Exosomes, extracellular vesicles of 30-150 nm in diameter, are increasingly studied and linked to tumourigenesis in oncology. These bilipid-membrane-bound vesicles are packaged with a variety of signalling molecules, mediating cell-cell communications. Within the TME, exosomes can originate from tumour, immune, or stromal cells. Although there are studies on tumour-derived exosomes (TEX) in NPC and their effects on tumour processes like angiogenesis, metastasis, therapeutic resistance, there is a lack of research on their involvement in immune evasion. In this review, we aim to enhance the comprehension of how NPC TEX contribute to cellular immunosuppression. Furthermore, considering the detectability of TEX in bodily fluids, we will also discuss the potential development of TEX-related biomarkers for liquid biopsy in NPC as this could facilitate early diagnosis and prognostication of the disease.

Mitochondrial non-coding RNA in nasopharyngeal carcinoma: Clinical diagnosis and functional analysis

Background: Nasopharyngeal carcinoma is a common head and neck cancer with high incidence in Southeast Asia. Despite advances in treatment, the diagnosis of NPC remains a challenge due to its non-specific symptoms and high rate of false negatives. In this study, we aimed to identify novel non-coding RNAs (ncRNAs) as diagnostic biomarkers for NPC. Mitochondrial non-coding RNAs (mtio-ncRNAs) have been shown to play important roles in regulating various cellular processes. However, their specific functions and underlying mechanisms are largely unknown. Methods: We investigated the expression and biological function of mtio-ncRNAs in the human NPC cell line C666-1. By using high-throughput sequencing, we identified several significantly expressed mtio-ncRNAs in C666-1 cells and analyzed their target genes and enriched pathways using tsRFUN. Results: Our results showed that these significantly expressed mtio-ncRNAs mainly enriched in Cancer Gene Neighborhoods and targeted genes GCM1 and ACTG1. To validate the bioinformatics predictions, we synthesized two mtio-ncRNAs, t00846456 and t00048674, and transfected them into C666-1 cells. Our results showed that the expression of GCM1 was significantly increased by transfection of t00846456, while the expression of ACTG1 was significantly increased by transfection of t0048674. Additionally, the migration ability of the transfected cells was also enhanced. Discussion: Our findings provide novel insights into the biological functions of mtio-ncRNAs and their potential applications in cancer diagnosis and treatment.

A panel of blood-derived miRNAs with a stable expression pattern as a potential pan-cancer detection signature

Introduction: MicroRNAs have a significant role in the regulation of the transcriptome. Several miRNAs have been proposed as potential biomarkers in different malignancies. However, contradictory results have been reported on the capability of miRNA biomarkers in cancer detection. The human biological clock involves molecular mechanisms that regulate several genes over time. Therefore, the sampling time becomes one of the significant factors in gene expression studies. Method: In the present study, we have tried to find miRNAs with minimum fluctuation in expression levels at different time points that could be more accurate candidates as diagnostic biomarkers. The small RNA-seq raw data of ten healthy individuals across nine-time points were analyzed to identify miRNAs with stable expression. Results: We have found five oscillation patterns. The stable miRNAs were investigated in 779 small-RNA-seq datasets of eleven cancer types. All miRNAs with the highest differential expression were selected for further analysis. The selected miRNAs were explored for functional pathways. The predominantly enriched pathways were miRNA in cancer and the P53-signaling pathway. Finally, we have found seven miRNAs, including miR-142-3p, miR-199a-5p, miR-223-5p, let-7d-5p, miR-148b-3p, miR-340-5p, and miR-421. These miRNAs showed minimum fluctuation in healthy blood and were dysregulated in the blood of eleven cancer types. Conclusion: We have found a signature of seven stable miRNAs which dysregulate in several cancer types and may serve as potential pan-cancer biomarkers.

Integrated Bioinformatics Analysis of Serine Racemase as an Independent Prognostic Biomarker in Endometrial Cancer

Endometrial cancer (EC) kills about 76,000 women worldwide, with the highest incidence in industrialized countries. Because of the rise in disease mortality and new diagnoses, EC is now a top priority for women’s health. Serine racemase (SRR) is thought to play a role in the central nervous system, but its role in cancers, particularly in EC, is largely unknown. The current study starts with a pan-cancer examination of SRR’s expression and prognostic value before delving into SRR’s potential cancer-suppressing effect in patients with EC. SRR may affect the endometrial tumor immune microenvironment, according to subsequent immune-related analysis. SRR expression is also linked to several genes involved in specific pathways such as ferroptosis, N6-methyladenosine methylation, and DNA damage repair. Finally, we used the expression, correlation, and survival analyses to investigate the upstream potential regulatory non-coding RNAs of SRR. Overall, our findings highlight the prognostic significance of SRR in patients with EC, and we can formulate a reasonable hypothesis that SRR influences metabolism and obstructs key carcinogenic processes in EC.

CircCRIM1 promotes nasopharyngeal carcinoma progression via the miR-34c-5p/FOSL1 axis

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a rare malignancy with multiple risk factors (Epstein-Barr virus, etc.) that seriously threatens the health of people. CircRNAs are known to regulate the tumorigenesis of malignant tumours, including NPC. Moreover, circCRIM1 expression is reported to be upregulated in NPC. Nevertheless, the impact of circCRIM1 on NPC progression is not clear.

METHODS

An MTT assay was performed to assess cell viability. In addition, cell invasion and migration were assessed by the transwell assay. Dual luciferase assays were performed to assess the association among circCRIM1, miR-34c-5p and FOSL1. Moreover, RT-qPCR was applied to assess mRNA levels, and protein levels were determined by Western blot.

RESULTS

CircCRIM1 and FOSL1 were upregulated in NPC cells, while miR-34c-5p was downregulated. Knockdown of circCRIM1 significantly decreased the invasion, viability and migration of NPC cells. The miR-34c-5p inhibitor notably promoted the malignant behaviour of NPC cells, while miR-34c-5p mimics exerted the opposite effect. Moreover, circCRIM1 could bind with miR-34c-5p, and FOSL1 was identified to be downstream of miR-34c-5p. Furthermore, circCRIM1 downregulation notably inhibited the proliferation and invasion of NPC cells, while this phenomenon was significantly reversed by FOSL1 overexpression.

CONCLUSION

Silencing circCRIM1 inhibited the tumorigenesis of NPC. Thus, circCRIM1 might be a novel target for NPC.

MicroRNAs/LncRNAs Modulate MDSCs in Tumor Microenvironment

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous group of immature cells derived from bone marrow that play critical immunosuppressive functions in the tumor microenvironment (TME), promoting cancer progression. According to base length, Non-coding RNAs (ncRNAs) are mainly divided into: microRNAs (miRNAs), lncRNAs, snRNAs and CircRNAs. Both miRNA and lncRNA are transcribed by RNA polymerase II, and they play an important role in gene expression under both physiological and pathological conditions. The increasing data have shown that MiRNAs/LncRNAs regulate MDSCs within TME, becoming one of potential breakthrough points at the investigation and treatment of cancer. Therefore, we summarize how miRNAs/lncRNAs mediate the differentiation, expansion and immunosuppressive function of tumor MDSCs in TME. We will then focus on the regulatory mechanisms of exosomal MicroRNAs/LncRNAs on tumor MDSCs. Finally, we will discuss how the interaction of miRNAs/lncRNAs modulates tumor MDSCs.

Nasopharyngeal Carcinoma and Its Microenvironment: Past, Current, and Future Perspectives

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy that raises public health concerns in endemic countries. Despite breakthroughs in therapeutic strategies, late diagnosis and drug resistance often lead to unsatisfactory clinical outcomes in NPC patients. The tumor microenvironment (TME) is a complex niche consisting of tumor-associated cells, such as fibroblasts, endothelial cells, leukocytes, that influences tumor initiation, progression, invasion, and metastasis. Cells in the TME communicate through various mechanisms, of note, exosomes, ligand-receptor interactions, cytokines and chemokines are active players in the construction of TME, characterized by an abundance of immune infiltrates with suppressed immune activities. The NPC microenvironment serves as a target-rich niche for the discovery of potential promising predictive or diagnostic biomarkers and the development of therapeutic strategies. Thus, huge efforts have been made to exploit the role of the NPC microenvironment. The whole picture of the NPC microenvironment remains to be portrayed to understand the mechanisms underlying tumor biology and implement research into clinical practice. The current review discusses the recent insights into the role of TME in the development and progression of NPC which results in different clinical outcomes of patients. Clinical interventions with the use of TME components as potential biomarkers or therapeutic targets, their challenges, and future perspectives will be introduced. This review anticipates to provide insights to the researchers for future preclinical, translational and clinical research on the NPC microenvironment.

Exosomes in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant epithelial tumor with a unique geographical distribution, primarily prevalent in East Africa and Asia. Although there is an increased understanding of the pathogenesis and risk factors of NPC, prevention and treatment efforts remain limited. Various studies have indicated that exosomes are actively involved in NPC by delivering biomolecules such as non-coding RNAs and proteins to target cells. In this review, we summarize the biological functions of exosomes in NPC and highlight their prospects as diagnostic biomarkers. In NPC, exosomes can manipulate the tumor microenvironment, participate in chemotherapy and radiation resistance, induce immune suppression, promote pathological angiogenesis, and support metastasis, and thus they could also be promising biomarkers. Because exosomes have essential effects and unusual biological properties, they have a promising future in diagnostic monitoring and prognostic evaluation. Although there are technical issues associated with using exosomes in large-scale applications, they have unparalleled advantages in assisting the clinical management of NPC.