miR-488-3p sponged by circ-0000495 and mediated upregulation of TROP2 in head and neck squamous cell carcinoma development

Circ_0003072 Mediates the Pro-osteogenic Differentiation Effect of Betulinic Acid on Human Periodontal Ligament Stem Cells

BACKGROUND

Betulinic acid (BetA) exhibits a good pro-osteogenic differentiation effect on human periodontal ligament stem cells (hPDLSCs), making it a promising supplement for periodontal regeneration. Circular RNAs (circRNAs) have emerged as important regulators of cellular behaviour, and whether circRNAs are involved in the effects of BetA remains unknown.

METHODS

Bioinformatics analysis was used to screen for dysregulated circRNAs involved in osteogenic differentiation based on public datasets. Osteogenic differentiation was evaluated using quantitative PCR detection of RUNX2, ALPL, COL1A1, and BGLAP levels, alkaline phosphatase staining, and Alizarin Red S staining of calcified nodules. The role of circ_0003072 in the BetA-regulated osteogenic differentiation of hPDLSCs was investigated, and its downstream microRNAs and mRNA were confirmed using RNA-sequencing, competing endogenous RNA network construction, gene ontology analysis, dual-luciferase reporter assays, and functional assays.

RESULTS

circ_0003072 showed the highest fold-change among the 18 candidate circRNAs, and knockdown of circ_0003072 inhibited the pro-osteogenic differentiation effect of BetA on hPDLSCs. RNA-sequencing combined with gene ontology analysis identified 11 osteogenesis-relevant genes. Five genes that shared microRNAs between circ_0003072 and two candidate genes (chordin-like 1 [CHRDL1] and XIAP) were screened, and miR-488-3p showed the highest increase after silencing circ_0003072. Knockdown of circ_0003072 inhibited the pro-osteogenic differentiation effect of silencing miR-488-3p. miR-488-3p bound to circ_0003072 and CHRDL1. Furthermore, overexpression of CHRDL1 rescued the miR-488-3p-induced inhibition of osteogenic differentiation.

CONCLUSION

BetA promoted the osteogenic differentiation of hPDLSCs by regulating the circ_0003072/miR-488-3p/CHRDL1 pathway, and circ_0003072 acted as a sponge for miR-488-3p, thus upregulating the level of CHRDL1.

Sacituzumab Govitecan in Patients with Relapsed/Refractory Advanced Head and Neck Squamous Cell Carcinoma: Results from the Phase II TROPiCS-03 Basket Study

PURPOSE

Treatment options for advanced head and neck squamous cell carcinoma (HNSCC) previously treated with platinum-based chemotherapy and a PD-1 inhibitor are limited. Trophoblast cell-surface antigen 2 (Trop-2) is highly expressed in HNSCC. Sacituzumab govitecan (SG) is a Trop-2-directed antibody-drug conjugate approved for patients with certain previously treated solid tumors.

PATIENTS AND METHODS

TROPiCS-03 (NCT03964727) is an open-label, multicohort, phase II study evaluating SG in advanced solid tumors, including HNSCC. Adults with locally advanced or metastatic HNSCC that progressed following platinum-based chemotherapy and anti-PD-(L)1 therapy [given sequentially (either order) or in combination] were administered SG 10 mg/kg on days 1 and 8 of a 21-day cycle. The primary endpoint was the investigator-assessed objective response rate. Secondary endpoints included duration of response, clinical benefit rate, progression-free survival, overall survival, and safety.

RESULTS

Patients (N = 43) received a median of 3 (range, 2-9) prior anticancer regimens. The objective response rate was 16% [95% confidence interval (CI), 7%-31%], with seven confirmed partial responses. The clinical benefit rate was 28% (95% CI, 15%-44%). The median (95% CI) duration of response, progression-free survival, and overall survival were 4.2 (2.6-not reached), 4.1 (2.6-5.8), and 9.0 (7.1-10.5) months, respectively. The most common treatment-emergent adverse events (TEAE) were diarrhea (47%), nausea (47%), and neutropenia (47%). Grade ≥3 TEAE occurred in 58% of patients. Three patients died from TEAE, with one event (septic shock) considered related to SG.

CONCLUSIONS

These data demonstrate the clinical potential of Trop-2-directed therapy in managing heavily pretreated patients with advanced HNSCC.

CircRNAs and miRNAs: Key Player Duo in Breast Cancer Dynamics and Biomarkers for Breast Cancer Early Detection and Prevention

Breast cancer (BC) remains a significant global health issue, necessitating advanced molecular approaches for early detection and prevention. This review delves into the roles of microRNAs (miRNAs) and circular RNAs (circRNAs) in BC, highlighting their potential as non-invasive biomarkers. Utilizing in silico tools and databases, we propose a novel methodology to establish mRNA/circRNA/miRNA axes possibly indicative of early detection and possible prevention. We propose that during early tumor initiation, some changes in oncogene or tumor suppressor gene expression (mRNA) are mirrored by alterations in corresponding circRNAs and reciprocal changes in sponged miRNAs affecting tumorigenesis pathways. We used two Gene Expression Omnibus (GEO) datasets and identified five mRNA/circRNA/miRNA axes as early possible tumor initiation biomarkers. We further validated the proposed axes through a Kaplan-Meier (KM) plot and enrichment analysis of miRNA expression using patient data. Evaluating coupled differential expression of circRNAs and miRNAs in body fluids or exosomes provides greater confidence than assessing either, with more axes providing even greater confidence. The proposed methodology not only improves early BC detection reliability but also has applications for other cancers, enhancing preventive measures.

CircVCAN promotes glioma progression through the miR-488-3p/MEF2C-JAGGED1 axis

Gliomas are the most prevalent primary malignant brain tumors worldwide. Growing evidences indicate that circular RNAs (circRNAs) play an important role in the regulation of biological behavior of tumors. We aimed to investigate the role and mechanism of circVCAN in glioma. RNase R treatment was utilized to assess the cyclic properties of circVCAN. CircVCAN, miR-488-3p, and myocyte enhancer factor 2C (MEF2C) levels in glioma tissues and cells were detected by reverse transcription real-time polymerase chain reaction (RT-qPCR), and the localization of them in glioma cells was determined with fluorescence in situ hybridization. Furthermore, a variety of biologically functional assessments were used to validate the role of circVCAN in glioma. The regulatory mechanisms of circVCAN, miR-488-3p, and MEF2C were further confirmed by double luciferase reporter gene assay, RNA immunoprecipitation and RNA pull-down assay, and the binding of MEF2C to JAGGED1 was revealed by chromatin immunoprecipitation. Additionally, a xenograft tumor model was constructed to demonstrate the effect of circVCAN on tumor growth in vivo. Our results indicated that circVCAN was more stable than its linear RNA and was significantly upregulated in gliomas. CircVCAN overexpression stimulated glioma cells to proliferate and metastasize, but circVCAN silencing exerted the opposite effect. Meanwhile, silencing circVCAN inhibited tumor growth in vivo. Moreover, we found that circVCAN interacted with miR-488-3p to regulate MEF2C expression, and miR-488-3p inhibition or MEF2C overexpression reversed the inhibitory effect on malignant bio-behaviors mediated by circVCAN knockdown in glioma cells. MEF2C promoted the transcription of JAGGED1, and circVCAN knockdown reduced the binding between MEF2C and JAGGED1. Collectively, circVCAN is a carcinogenic circRNA in glioma, and the circVCAN/miR-488-3p/MEF2C-JAGGED1 axis could serve as a potential target for the management of glioma.

Brain microvascular endothelial cell-derived exosomes transmitting circ_0000495 promote microglial M1-polarization and endothelial cell injury under hypoxia condition

Human brain microvascular endothelial cells (HBMVECs) and microglia play critical roles in regulating cerebral homeostasis during ischemic stroke. However, the role of HBMVECs-derived exosomes in microglia polarization after stroke remains unknown. We isolated exosomes (Exos) from oxygen glucose deprivation (OGD)-exposed HBMVECs, before added them into microglia. Microglia polarization markers were tested using RT-qPCR or flow cytometry. Inflammatory cytokines were measured with ELISA. Endothelial cell damage was assessed by cell viability, apoptosis, apoptosis-related proteins, oxidative stress, and angiogenic activity using CCK-8, flow cytometry, western blot, ELISA, and endothelial tube formation assay, respectively. We also established middle cerebral artery occlusion (MCAO) mice model to examine the function of circ_0000495 on stroke in vivo. Our study found that HBMVECs-Exos reduced M2 markers (IL-10, CD163, and CD206), increased M1 markers (TNF-α, IL-1β, and IL-12), CD86-positive cells, and inflammatory cytokines (TNF-α and IL-1β), indicating the promotion of microglial M1-polarization. Microglial M1-polarization induced by HBMVECs-Exos reduced viability and promoted apoptosis and oxidative stress, revealing the aggravation of endothelial cell damage. However, circ_0000495 silencing inhibited HBMVECs-Exos-induced alterations. Mechanistically, circ_0000495 adsorbed miR-579-3p to upregulate toll-like receptor 4 (TLR4) in microglia; miR-579-3p suppressed HBMVECs-Exos-induced alterations via declining TLR4; furthermore, Yin Yang 1 (YY1) transcriptionally activated circ_0000495 in HBMVECs. Importantly, circ_0000495 aggravated ischemic brain injury in vivo via activating TLR4/nuclear factor-κB (NF-κB) pathway. Collectively, OGD-treated HBMVECs-Exos transmitted circ_0000495 to regulate miR-579-3p/TLR4/NF-κB axis in microglia, thereby facilitating microglial M1-polarization and endothelial cell damage.

Effects of non-coding RNAs and RNA-binding proteins on mitochondrial dysfunction in diabetic cardiomyopathy

Vascular complications are the main cause of diabetes mellitus-associated morbidity and mortality. Oxidative stress and metabolic dysfunction underly injury to the vascular endothelium and myocardium, resulting in diabetic angiopathy and cardiomyopathy. Mitochondrial dysfunction has been shown to play an important role in cardiomyopathic disruptions of key cellular functions, including energy metabolism and oxidative balance. Both non-coding RNAs and RNA-binding proteins are implicated in diabetic cardiomyopathy, however, their impact on mitochondrial dysfunction in the context of this disease is largely unknown. Elucidating the effects of non-coding RNAs and RNA-binding proteins on mitochondrial pathways in diabetic cardiomyopathy would allow further insights into the pathophysiological mechanisms underlying diabetic vascular complications and could facilitate the development of new therapeutic strategies. Stem cell-based models can facilitate the study of non-coding RNAs and RNA-binding proteins and their unique characteristics make them a promising tool to improve our understanding of mitochondrial dysfunction and vascular complications in diabetes.

MicroRNA-488: A miRNA with diverse roles and clinical applications in cancer and other human diseases

MicroRNAs (miRNAs) are a class of small non-coding RNAs that post-transcriptionally regulate the expression of approximately 50 % of all protein-coding genes. They have been demonstrated to act as key regulators in various pathophysiological processes and play significant roles in a wide range of human diseases, particularly cancer. Current research highlights the aberrant expression of microRNA-488 (miR-488) in multiple human diseases and its critical involvement in disease initiation and progression. Moreover, the expression level of miR-488 has been linked to clinicopathological features and patient prognosis across different diseases. However, a comprehensive systematic review of miR-488 is lacking. Therefore, our study aims to consolidate the current knowledge surrounding miR-488, with a primary focus on its emerging biological functions, regulatory mechanisms, and potential clinical applications in human diseases. Through this review, we aim to establish a comprehensive understanding of the diverse roles of miR-488 in the development of various diseases.

LncRNA PVT1 Promotes Neuronal Cell Apoptosis and Neuroinflammation by Regulating miR-488-3p/FOXD3/SCN2A Axis in Epilepsy

It is vital to understand the mechanism of epilepsy onset and development. Dysregulated lncRNAs are closely associated with epilepsy. Our work probed the role of lncRNA PVT1/miR-488-3p/FOXD3/SCN2A axis in epilepsy. The mRNA and protein expressions were assessed using qRT-PCR and western blot. MTT assay and TUNEL staining were conducted to assess cell viability and apoptosis, respectively. TNFα, IL-1β and IL-6 levels were analyzed using ELISA. LDH level was tested by Assay Kit. The binding relationship between PVT1, miR-488-3p and FOXD3 were verified using dual luciferase reporter gene assay. The epilepsy model of rats was established by lithium-pilocarpine injection. Nissl staining was performed to evaluate neuronal damage. PVT1 was markedly upregulated in epilepsy model cells. Knockdown of PVT1 increased the viability, while repressed the apoptosis and inflammatory cytokines secretion as well as LDH level in epilepsy cell model. MiR-488-3p alleviated neuronal injury and neuroinflammation in model cells. MiR-488-3p functioned as the direct target of PVT1, and its inhibition neutralized the effects of PVT1 silencing on neuronal cell injury and neuroinflammation in model cells. Furthermore, miR-488-3p inhibited neuronal cell injury and neuroinflammation in model cells by regulating FOXD3/SCN2A pathway. Finally, animal experiments proved that PVT1 promoted epilepsy-induced neuronal cell injury and neuroinflammation by regulating miR-488-3p-mediated FOXD3/SCN2A pathway. PVT1 promoted neuronal cell injury and inflammatory response in epilepsy via inhibiting miR-488-3p and further regulating FOXD3/SCN2A pathway.

A Circular RNA, hsa_circ_0018180 (circPARD3), Triggers Glycolysis and Promotes Malignancy of Head and Neck Squamous Cell Carcinoma Through the miR-5194/ENO1 Axis

Emerging evidence has demonstrated the pivotal roles of circular RNAs (circRNAs) in the modulation of malignancy and pathological progression among multiple human cancers. Glucose metabolism reprogramming is a widely identified characteristic for contributing to facilitate tumorigenesis. Nonetheless, their contributions to head and neck squamous cell carcinoma (HNSCC) cell glycolysis remain to be further elucidated. Herein, we aim to investigate the role of circRNA, hsa_circ_0018180 (also named as circPARD3) in HNSCC. Expression patterns of circPARD3 in HNSCC tissues and different cell lines were determined by qRT-PCR assay, as well as its correlation with the prognosis of survival. CCK-8, EdU incorporation, and transwell assays were carried out to assess the cell viability, proliferation, migration, and invasion, respectively. Glucose uptake and lactate production were evaluated by preforming glycolysis. Mechanistically, the circPARD3/miR-5194/ENO1 axis was verified by RNA immunoprecipitation (RIP) and luciferase reporter assays. Western blot analysis was employed to measure the epithelial-mesenchymal transition (EMT)-associated biomarkers. Upregulated circPARD3 observed in HNSCC tissues and cell lines indicated the poor prognosis of patients. Stable knockdown of circPARD3 dramatically exerted the suppressive effects on cell viability, proliferation, migration, and invasion, as well as glucose uptake and lactate production. Mechanistically, circPARD3 harbored miR-5194, serving as a miRNA sponge, thereby increasing ENO1 expression. Moreover, ENO1 evidently reversed miR-5194-mediated attenuated malignant behaviors. Collectively, our study identified an oncogenic role of circPARD3 in HNSCC through a novel machinery of circPARD3/miR-5194/ENO1 and provided a promising therapeutic target for HNSCC.

The expression profile and clinical application value of hsa_circ_0016148 in head and neck squamous cell carcinoma

Background

Dysregulated circular RNAs (circRNAs) are involved in human cancers and may be used as biomarkers with the potential of clinical application. However, little is known regarding the mechanism of circRNAs and their clinical application value in head and neck squamous cell carcinoma (HNSCC).

Methods

In the current study, we established the profile of circRNAs in HNSCC using microarray and then measured the expression of hsa_circ_0016148 in 137 paired HNSCC tissues by qRT‐PCR technique, analyzed the relationship between hsa_circ_0016148 and clinicopathological data, and investigated its diagnostic and prognostic value. The hsa_circ_0016148‐miRNA‐mRNA interaction network was predicted and constructed by Cytoscape.

Results

Our study showed a circRNA expression profile and confirmed downregulated hsa_circ_0016148 in HNSCC tissues (p = 2.64E‐35). The hsa_circ_0016148 expression is remarkably correlated with lymph node metastasis (p = 0.001) and clinical stage (p = 0.029). Then, the area under the receiver characteristic curve (AUC) was 0.912 with 92% of sensitivity and 86.9% specificity, respectively. Besides, our study demonstrated that lower‐expressed hsa_circ_0016148 could independently predict poorer overall survival of HNSCC patients (hazard ratio [HR] = 0.456; 95% confidence interval [CI] = 0.265–0.784; p = 0.005). The hsa_circ_0016148‐miRNA‐mRNA interaction network was constructed, which included a total of nine targeted miRNAs.

Conclusion

Taken together, our results revealed that hsa_circ_0016148 might play a critical role in HNSCC tumorigenesis and may serve as an indicator with the potential of diagnosis and prognosis for HNSCC.

The circ_0032822 Promotes the Proliferation of Head and Neck Squamous Cell Carcinoma Cells Through miR-141/EF3 Signaling Axis

Head and neck squamous cell carcinoma (HNSCC) refers to an epithelial malignant tumor that originates in the head and neck, and over 600,000 new cases are reported every year, However, the overall prognosis is still poor due to local recurrence and distant metastasis after surgery. The circ_0032822 has been reported upregulated in human oral squamous cell carcinoma; however, the detailed function or mechanism remains unknown. In this study, we confirmed the upregulation of circ_0032822 in HNSCC tumor tissues. Functionally, the overexpression of circ_0032822 significantly promoted the proliferation of HNSCC cell lines along with the S phase arrest and reduced apoptosis, while downregulation of circ_0032822 has the opposite effect in vitro. Mechanistic analysis showed that circ_0032822 acted as a competing endogenous RNA of miR-141 to diminish the repressive effect of miR-141 on its target E2F3. In conclusion, we demonstrated that circ_0032822 functions as a tumor oncogene in HNSCC and that its function is regulated via the miR-141/E2F3 axis.

Trop2: Jack of All Trades, Master of None

Trophoblast cell surface antigen 2 (Trop2) is a widely expressed glycoprotein and an epithelial cell adhesion molecule (EpCAM) family member. Although initially identified as a transmembrane protein, other subcellular localizations and processed forms were described. Its congenital mutations cause a gelatinous drop-like corneal dystrophy, a disease characterized by loss of barrier function in corneal epithelial cells. Trop2 is considered a stem cell marker and its expression associates with regenerative capacity in various tissues. Trop2 overexpression was described in tumors of different origins; however, functional studies revealed both oncogenic and tumor suppressor roles. Nevertheless, therapeutic potential of Trop2 was recognized and clinical studies with drug-antibody conjugates have been initiated in various cancer types. One of these agents, sacituzumab govitecan, has been recently granted an accelerated approval for therapy of metastatic triple-negative breast cancer. In this article, we review the current knowledge about the yet controversial function of Trop2 in homeostasis and pathology.

Construction of an 11-microRNA-based signature and a prognostic nomogram to predict the overall survival of head and neck squamous cell carcinoma patients

Background

Head and neck squamous cell carcinoma (HNSCC) is a fatal malignancy owing to the lack of effective tools to predict overall survival (OS). MicroRNAs (miRNAs) play an important role in HNSCC occurrence, development, invasion and metastasis, significantly affecting the OS of patients. Thus, the construction of miRNA-based risk signatures and nomograms is desirable to predict the OS of patients with HNSCC. Accordingly, in the present study, miRNA sequencing data of 71 HNSCC and 13 normal samples downloaded from The Cancer Genome Atlas (TCGA) were screened to identify differentially expressed miRNAs (DEMs) between HNSCC patients and normal controls. Based on the exclusion criteria, the clinical information and miRNA sequencing data of 67 HNSCC samples were selected and used to establish a miRNA-based signature and a prognostic nomogram. Forty-three HNSCC samples were assigned to an internal validation cohort for verifying the credibility and accuracy of the primary cohort. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to explore the functions of 11 miRNA target genes.

Results

In total, 11 DEMs were successfully identified. An 11-miRNA risk signature and a prognostic nomogram were constructed based on the expression levels of these 11 DEMs and clinical information. The signature and nomogram were further validated by calculating the C-index, area under the curve (AUC) in receiver-operating characteristic curve analysis, and calibration curves, which revealed their promising performance. The results of the internal validation cohort shown the reliable predictive accuracy both of the miRNA-based signature and the prognostic nomogram. GO and KEGG analyses revealed that a mass of signal pathways participated in HNSCC proliferation and metastasis.

Conclusion

Overall, we constructed an 11-miRNA-based signature and a prognostic nomogram with excellent accuracy for predicting the OS of patients with HNSCC.