Inhibition of long non-coding RNA MALAT1 elevates microRNA-429 to suppress the progression of hypopharyngeal squamous cell carcinoma by reducing ZEB1

Epithelial‑derived head and neck squamous tumourigenesis (Review)

Head and neck squamous cell carcinomas (HNSCCs), a heterogeneous group of cancers that arise from the mucosal epithelia cells in the head and neck areas, present great challenges in diagnosis, treatment and prognosis due to their complex aetiology and various clinical manifestations. Several factors, including smoking, alcohol consumption, oncogenic genes, growth factors, Epstein‑Barr virus and human papillomavirus infections can contribute to HNSCC development. The unpredictable tumour microenvironment adds to the complexity of managing HNSCC. Despite significant advances in therapies, the prediction of outcome after treatment for patients with HNSCC remains poor, and the 5‑year overall survival rate is low due to late diagnosis. Early detection greatly increases the chances of successful treatment. The present review aimed to bring together the latest findings related to the molecular mechanisms of HNSCC carcinogenesis and progression. Comprehensive genomic, transcriptomic, metabolomic, microbiome and proteomic analyses allow researchers to identify important biological markers such as genetic alterations, gene expression signatures and protein markers that drive HNSCC tumours. These biomarkers associated with the stages of initiation, progression and metastasis of cancer are useful in the management of patients with cancer in order to improve their life expectancy and quality of life.

Long non-coding RNA PVT1 regulates TGF-β and promotes the proliferation, migration and invasion of hypopharyngeal carcinoma FaDu cells

Hypopharyngeal carcinoma is one of the malignant tumors of the head and neck with a particularly poor prognosis. Recurrence and metastasis are important reasons for poor prognosis of hypopharyngeal cancer patients, and malignant proliferation, migration, and invasion of tumor cells are important factors for recurrence and metastasis of hypopharyngeal cancer. Therefore, elucidating hypopharyngeal cancer cells' proliferation, migration, and invasion mechanism is essential for improving diagnosis, treatment, and prognosis. Plasmacytoma Variant Translocation 1 (PVT1) is considered a potential diagnostic marker and therapeutic target for tumors. However, it remains unclear whether PVT1 is related to the occurrence and development of hypopharyngeal cancer and its specific mechanism. In this study, the promoting effect of PVT1 on the proliferation, migration, and invasion of hypopharyngeal carcinoma FaDu cells was verified by cell biology experiments and animal studies, and it was found that PVT1 inhibited the expression of TGF-β, suggesting that PVT1 may regulate the occurrence and development of hypopharyngeal carcinoma FaDu cells through TGF-β.

Exploration of the association between HIF3α mRNA and lncRNA MALAT1 in laryngeal squamous cell carcinoma by correlation analysis

Laryngeal squamous cell carcinoma (LSCC) is a significant global health burden, for which there has been limited evidence of improved survival rates. Although the roles of hypoxia-inducible factor (HIF)1α and HIF2α have been well documented in hypoxia, the involvement of HIF3α, particularly in LSCC, has been inadequately explored. The present study aimed to investigate the correlation between HIFα subunits and the hypoxia-related long noncoding RNAs (lncRNAs) MALAT1 and HOTAIR in 63 patients diagnosed with LSCC. Total RNA was extracted from fresh-frozen laryngeal tumor and adjacent normal tissues, and was subjected to reverse transcription-quantitative PCR for target detection. Statistical analyses were conducted using SPSS software, with significance set at P<0.05. The present study is the first, to the best of our knowledge, to report a positive moderate monotonic correlation (rs=0.347) and moderately strong positive linear correlation (r=0.630) between HIF3α mRNA and lncRNA MALAT1 in LSCC. Regression analysis revealed a direct association between 39.6% of both variables. Additionally, a positive correlation was observed between lncRNAs MALAT1 and HOTAIR (rs=0.353); HIF2α mRNA and lncRNA MALAT1 (rs=0.431); HIF3α mRNA and lncRNA HOTAIR (rs=0.279); and HIF3α mRNA and HIF2α mRNA (rs=0.285). Notably, a significant negative correlation (rs=-0.341) was detected between HIF3α mRNA and HIF1α mRNA, potentially indicative of the HIF switch or negative regulation. In addition, the present study investigated the association between HIFα subunits and the clinicopathological characteristics of patients. The results revealed a notable association between HIF1α transcript levels and the location of LSCC; specifically, subglottic tumors exhibited elevated HIF1α levels compared with glottic and supraglottic LSCC. Furthermore, a significant association was identified between HIF3α transcript levels and patient age (P=0.032) and positive family history (P=0.047). In conclusion, the present findings suggested a pivotal role for HIF3α in LSCC development, potentially involving direct regulation of lncRNA MALAT1. However, further research is warranted to elucidate its precise mechanisms.

Low-dose Lipopolysaccharide Alleviates Spinal Cord Injury-induced Neuronal Inflammation by Inhibiting microRNA-429-mediated Suppression of PI3K/AKT/Nrf2 Signaling

This study investigated the impact of low-dose lipopolysaccharide (LPS) on spinal cord injury (SCI) and the potential molecular mechanism. Rats were randomly assigned to four groups: Sham, SCI, SCI + LPS, and SCI + LPS + agomir. Allen's weight-drop method was used to establish an in vivo SCI model. The Basso Bcattie Bresnahan rating scale was employed to monitor locomotor function. An in vitro SCI model was constructed by subjecting PC12 cells to oxygen and glucose deprivation/ reoxygenation (OGD/R). Enzyme-linked immunosorbent assay (ELISA) was applied for the determination interleukin (IL)-1β and IL-6. The dual luciferase reporter assay was used to validate the targeting of microRNA (miR)-429 with PI3K. Immunohistochemical staining was used to assess the expression of PI3K, phosphorylated AKT and Nrf2 proteins. The Nrf2-downstream anti-oxidative stress proteins, OH-1 and NQO1, were detected by western blot assay. MiR-429 expression was detected by fluorescence in situ hybridization and real-time quantitative reverse transcription PCR. In vitro, low-dose LPS decreased miR-429 expression, activated PI3K/AKT/Nrf2, inhibited oxidative stress and inflammation, and attenuated SCI. MiR-429 was found to target and negatively regulate PI3K. Inhibition of miR-429 suppressed low-dose LPS-mediated oxidative stress and inflammation via activation of the PI3K/AKT/Nrf2 pathway. In vivo, miR-429 was detectable in neurons. Inhibition of miR-429 blocked low-dose LPS-mediated oxidative stress and inflammation via activation of the PI3K/AKT/Nrf2 pathway. Overall, low-dose LPS was found to alleviate SCI-induced neuronal oxidative stress and inflammatory response by down-regulating miR-429 to activate the PI3K/AKT/Nrf2 pathway.

HIF-1-Induced hsa-miR-429: Understanding Its Direct Targets as the Key to Developing Cancer Diagnostics and Therapies

MicroRNAs (miRNAs) play a critical role in the regulation of mRNA stability and translation. In spite of our present knowledge on the mechanisms of mRNA regulation by miRNAs, the utilization and translation of these ncRNAs into clinical applications have been problematic. Using hsa-miR-429 as an example, we discuss the limitations encountered in the development of efficient miRNA-related therapies and diagnostic approaches. The miR-200 family members, which include hsa-miR-429, have been shown to be dysregulated in different types of cancer. Although these miR-200 family members have been shown to function in suppressing epithelial-to-mesenchymal transition, tumor metastasis, and chemoresistance, the experimental results have often been contradictory. These complications involve not only the complex networks involving these noncoding RNAs, but also the problem of identifying false positives. To overcome these limitations, a more comprehensive research strategy is needed to increase our understanding of the mechanisms underlying their biological role in mRNA regulation. Here, we provide a literature analysis of the verified hsa-miR-429 targets in various human research models. A meta-analysis of this work is presented to provide better insights into the role of hsa-miR-429 in cancer diagnosis and any potential therapeutic approach.

Small biomarkers with massive impacts: PI3K/AKT/mTOR signalling and microRNA crosstalk regulate nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumours of the head and neck in Southeast Asia and southern China. The Phosphatidylinositol 3-kinase/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signalling pathway is involved in processes related to tumour initiation/progression, such as proliferation, apoptosis, metastasis, and drug resistance, and is closely related to the clinicopathological features of NPC. In addition, key genes involved in the PI3K/AKT/mTOR signalling pathway undergo many changes in NPC. More interestingly, a growing body of evidence suggests an interaction between this signalling pathway and microRNAs (miRNAs), a class of small noncoding RNAs. Therefore, in this review, we discuss the interactions between key components of the PI3K/AKT/mTOR signalling pathway and various miRNAs and their importance in NPC pathology and explore potential diagnostic biomarkers and therapeutic targets.

lncRNA LEF1-AS1 Acts as a Novel Biomarker and Promotes Hypopharyngeal Squamous Cell Carcinoma Progression and Metastasis by Targeting the miR-221-5p/GJA1 Axis

Hypopharyngeal squamous cell carcinoma (HSCC) is highly malignant and extremely aggressive, making it one of the worst prognoses among all kinds of head and neck squamous cell carcinoma (HNSCC); therefore, gaining insight into molecular mechanisms of HSCC is of profound significance. In the current manuscript, we revealed the elevated expression of long noncoding RNA (lncRNA) LEF1-AS1 in HNSCC which was associated with the poor prognosis by bioinformatic analysis. Moreover, we noticed that LEF1-AS1 dramatically accelerated the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) process in HSCC cell line FaDu. Most importantly, we illustrated that LEF1-AS1 played as a competitive endogenous RNA (ceRNA) via sponging miR-221-5p and thereby positively regulated gap junction protein alpha 1 (GJA1) expression, thus aggravated tumor progression and EMT. In conclusion, for the first time, we demonstrated lncRNA LEF1-AS1 as a novel biomarker for HNSCC and suggested LEF1-AS1/miR-221-5p/GJA1 axis as promising diagnostic and therapeutic target for HSCC treatment.

RNF185 antisense RNA 1 (RNF185-AS1) promotes proliferation, migration, and invasion in papillary thyroid carcinoma

Long noncoding RNA (lncRNA) plays an important role in multiple cancers. So far, the exact function of lncRNAs in papillary thyroid carcinoma (PTC) is unclear. The purposes of this work were to investigate the function and underlying mechanisms of RNF185 antisense RNA 1 (RNF185-AS1) in PTC. The expression of RNF185-AS1 was analyzed by quantitative real-time PCR (qRT-PCR). Colony formation, 5-ethynyl-2'-deoxyuridine, and Cell Counting Kit-8 assays were utilized to determine cell proliferation. Cell migration and invasion were tested using wound healing and transwell assays. A mouse transplantation tumor model was used for tumor growth analyses in vivo. The regulation of RNF185-AS1 on the downstream miR-429/lipoprotein receptor-related protein (LRP4) axis was predicted and identified through bioinformatic analysis, dual-luciferase reporter assay, and RNA immunoprecipitation (RIP) assay. RNF185-AS1 was dramatically overexpressed in PTC tumors and cells. High RNF185-AS1 expression was associated with bigger tumor size, lymph node metastasis, and advanced tumor-node-metastasis stage in PTC patients. Silencing of RNF185-AS1 impeded the proliferation, migration, and invasion in vitro and constrained tumorigenesis in vivo. Mechanistically, RNF185-AS1 could act as a sponge of miR-429 to regulate the expression of LRP4. In addition, downregulation of miR-429 or upregulation of LRP4 could relieve the proliferation, migration, and invasion of IHH-4 and TPC-1 cells that inhibited by RNF185-AS1 knockdown. Downregulation of RNF185-AS1 may suppress PTC progression through functioning as a sponge of miR-429 to hinder the expression of LRP4. The RNF185-AS1/miR-429/LRP4 axis will lay the groundwork for future therapeutic strategies in PTC.

Metastatic EMT Phenotype Is Governed by MicroRNA-200-Mediated Competing Endogenous RNA Networks

Epithelial–mesenchymal transition (EMT) is a fundamental physiologically relevant process that occurs during morphogenesis and organ development. In a pathological setting, the transition from epithelial toward mesenchymal cell phenotype is hijacked by cancer cells, allowing uncontrolled metastatic dissemination. The competing endogenous RNA (ceRNA) hypothesis proposes a competitive environment resembling a large-scale regulatory network of gene expression circuits where alterations in the expression of both protein-coding and non-coding genes can make relevant contributions to EMT progression in cancer. The complex regulatory diversity is exerted through an array of diverse epigenetic factors, reaching beyond the transcriptional control that was previously thought to single-handedly govern metastatic dissemination. The present review aims to unravel the competitive relationships between naturally occurring ceRNA transcripts for the shared pool of the miRNA-200 family, which play a pivotal role in EMT related to cancer dissemination. Upon acquiring more knowledge and clinical evidence on non-genetic factors affecting neoplasia, modulation of the expression levels of diverse ceRNAs may allow for the development of novel prognostic/diagnostic markers and reveal potential targets for the disruption of cancer-related EMT.

The Role and Mechanism of MALAT1 Long Non-Coding RNA in the Diagnosis and Treatment of Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is the most common malignant tumor of the head and neck. HNSCC mainly affects the oral cavity and the laryngeal, laryngopharyngeal, and oropharyngeal tracts. The high incidence, hidden onset, low survival rate, and unsatisfactory effects of treatment effect underscore the importance of identify the mechanisms of HNSCC occurrence and development. Although there is a very urgent need for early diagnosis and treatment, there are currently no reliable early HNSCC diagnosis biomarkers or effective treatment targets. Long non-coding RNA (lncRNA) is widely involved in biological processes, especially as a key regulator of tumorigenesis and development. Lung adenocarcinoma metastasis-associated transcript 1 (MALAT1) is an important member of the lncRNA family that can regulate the occurrence and development of a variety of malignant tumors and is anticipated to be an ideal marker for early tumor diagnosis and an effective therapeutic target. Here, we review the research progress into the role of MALAT1 in the diagnosis and treatment of HNSCC and its regulatory mechanism.

Plasma cell-free circRNAs panel act as fingerprint predicts the occurrence of laryngeal squamous cell carcinoma

Background: Circular RNAs (circRNAs) have recently emerged as a new class of RNAs, highly enriched in the human tissues and very stable within cells, exosomes and body fluids. In this study, we aimed to screen the plasma cell-free derived circRNAs in laryngeal squamous cell carcinoma (LSCC) and investigate whether these circRNAs could predicted LSCC as potential biomarkers.

Methods: The circRNA microarray was employed with three samples in each group to screen the dysregulated circRNAs isolated from plasma samples. The top 20 circRNAs were first selected as candidates with the upregulated level in the plasma of LSCC.

Results: Further validation found that only circ_0019201, circ_0011773 and circ_0122790 was consistent with training set. The ROC curve also revealed a high diagnostic ability an area under ROC curve value (AUC) for single circRNA and combined. The AUC for circ_0019201, circ_0011773 and circ_0122790 and the combined was 0.933, 0.908, 0.965 and 0.990 in training set. For the validation set, the AUC was 0.766, 0.864, 0.908 and 0.951. The three circRNAs were further investigated with stable expression in human plasma samples.

Conclusions: The plasma derived circ_0019201, circ_0011773 and circ_0122790 might be the potential biomarker for predicting the LSCC.

Variation of PPARG Expression in Chemotherapy-Sensitive Patients of Hypopharyngeal Squamous Cell Carcinoma

Our previous study showed that the upregulation of peroxisome proliferator-activated receptor gamma (PPARG) could promote chemosensitivity of hypopharyngeal squamous cell carcinoma (HSCC) in chemotherapeutic treatments. Here, we acquired two more independent expression data of PPARG to validate the expression levels of PPARG in chemotherapy-sensitive patients (CSP) and its individualized variations compared to chemotherapy-non-sensitive patients (CNSP). Our results showed that overall PPARG expression was mildly downregulated (log fold change = −0.55; p value = 0.42; overexpression in three CSPs and reduced expression in four CSPs), which was not consistent with previous results (log fold change = 0.50; p = 0.22; overexpression in nine CSPs and reduced expression in three CSPs). Both studies indicated that PPARG expression variation was significantly associated with the Tumor-Node-Metastasis (TNM) stage (p = 7.45e − 7 and 6.50e − 4, for the first and second studies, respectively), which was used as one of the predictors of chemosensitivity. The new dataset analysis revealed 51 genes with significant gene expression changes in CSPs (LFC > 1 or <-1; p value < 0.01), and two of them (TMEM45A and RBP1) demonstrated strong coexpression with PPARG (Pearson correlation coefficient > 0.6 or <-0.6). There were 21 significant genes in the data from the first study, with no significant association with PPARG and no overlap with the 51 genes revealed in this study. Our results support the connection between PPARG and chemosensitivity in HSCC tumor cells. However, significant PPARG variation exists in CSPs, which may be influenced by multiple factors, including the TNM stage.

Comprehensive Analysis of Correlations in the Expression of miRNA Genes and Immune Checkpoint Genes in Bladder Cancer Cells

Personalised medicine is the future and hope for many patients, including those with cancers. Early detection, as well as rapid, well-selected treatment, are key factors leading to a good prognosis. MicroRNA mediated gene regulation is a promising area of development for new diagnostic and therapeutic methods, crucial for better prospects for patients. Bladder cancer is a frequent neoplasm, with high lethality and lacking modern, advanced therapeutic modalities, such as immunotherapy. MicroRNAs are involved in bladder cancer pathogenesis, proliferation, control and response to treatment, which we summarise in this perspective in response to lack of recent review publications in this field. We further performed a correlation-based analysis of microRNA and gene expression data in bladder cancer (BLCA) TCGA dataset. We identified 27 microRNAs hits with opposite expression profiles to genes involved in immune response in bladder cancer, and 24 microRNAs hits with similar expression profiles. We discuss previous studies linking the functions of these microRNAs to bladder cancer and assess if they are good candidates for personalised medicine therapeutics and diagnostics. The discussed functions include regulation of gene expression, interplay with transcription factors, response to treatment, apoptosis, cell proliferation and angiogenesis, initiation and development of cancer, genome instability and tumour-associated inflammatory reaction.