LncRNA GACAT1 induces tongue squamous cell carcinoma migration and proliferation via miR-149

Novel insights on oral squamous cell carcinoma management using long non-coding RNAs

Oral squamous cell carcinoma (OSCC) is one of the most prevalent forms of head and neck squamous cell carcinomas (HNSCC) with a poor overall survival rate (about 50%), particularly in cases of metastasis. RNA-based cancer biomarkers are a relatively advanced concept, and non-coding RNAs currently have shown promising roles in the detection and treatment of various malignancies. This review underlines the function of long non-coding RNAs (lncRNAs) in the OSCC and its subsequent clinical implications. LncRNAs, a class of non-coding RNAs, are larger than 200 nucleotides and resemble mRNA in numerous ways. However, unlike mRNA, lncRNA regulates multiple druggable and non-druggable signaling molecules through simultaneous interaction with DNA, RNA, proteins, or microRNAs depending on concentration and localization in cells. Upregulation of oncogenic lncRNAs and down-regulation of tumor suppressor lncRNAs are evident in OSCC tissues and body fluids such as blood and saliva indicating their potential as valuable biomarkers. Targeted inhibition of candidate oncogenic lncRNAs or over-expression of tumor suppressor lncRNAs showed potential therapeutic roles in in-vivo animal models. The types of lncRNAs that are expressed differentially in OSCC tissue and bodily fluids have been systematically documented with specificity and sensitivity. This review thoroughly discusses the biological functions of such lncRNAs in OSCC cell survival, proliferation, invasion, migration, metastasis, angiogenesis, metabolism, epigenetic modification, tumor immune microenvironment, and drug resistance. Subsequently, we addressed the diagnostic and therapeutic importance of lncRNAs in OSCC pre-clinical and clinical systems, providing details on ongoing research and outlining potential future directions for advancements in this field. In essence, this review could be a valuable resource by offering comprehensive and current insights into lncRNAs in OSCC for researchers in fundamental and clinical domains.

RP11-495P10.1 promotes HCC cell proliferation by regulating reprogramming of glucose metabolism and acetylation of the NR4A3 promoter via the PDK1/PDH axis

The incidence and related death of hepatocellular carcinoma (HCC) have increased over the past decades. However, the molecular mechanisms underlying HCC pathogenesis are not fully understood. Long noncoding RNA (lncRNA) RP11-495P10.1 has been proven to be closely associated with the progression of prostate cancer, but its role and specific mechanism in HCC are still unknown. Here, we identify that RP11-495P10.1 is highly expressed in HCC tissues and cells and contributes to the proliferation of HCC cells. Moreover, this study demonstrates that RP11-495P10.1 affects the proliferation of HCC by negatively regulating the expression of nuclear receptor subfamily 4 group a member 3 (NR4A3). Glycometabolism reprogramming is one of the main characteristics of tumor cells. In this study, we discover that RP11-495P10.1 regulates glycometabolism reprogramming by changing the expression of pyruvate dehydrogenase kinase 1 (PDK1) and pyruvate dehydrogenase (PDH), thus contributing to the proliferation of HCC cells. Furthermore, knockdown of RP11-495P10.1 increases enrichment of H3K27Ac in the promoter of NR4A3 by promoting the activity of PDH and the production of acetyl-CoA, which leads to the increased transcription of NR4A3. Altogether, RP11-495P10.1 promotes HCC cell proliferation by regulating the reprogramming of glucose metabolism and acetylation of the NR4A3 promoter via the PDK1/PDH axis, which provides an lncRNA-oriented therapeutic strategy for the diagnosis and treatment of HCC.

FDFT1 repression by piR-39980 prevents oncogenesis by regulating proliferation and apoptosis through hypoxia in tongue squamous cell carcinoma

AIM

Tongue squamous cell carcinoma (TSCC) is one of the most aggressive tumors whose underlying molecular mechanism remains elusive. Previous studies have identified piR-39980, a non-coding RNA, as a tumour suppressor or oncogene in different malignancies and the cholesterogenic protein, Farnesyl-Diphosphate Farnesyltransferase 1 (FDFT1) playing critical roles in cancer. The present study investigates the role of piR-39980, and its target FDFT1, in regulating the malignancy of TSCC.

MAIN METHODS

We performed qRT-PCR to determine the expression of FDFT1, piR-39980 and validated FDFT1 as a target of piR-39980 by dual luciferase assay. Then, to investigate the role of FDFT1 overexpression and piR-39980's inhibitory effect on FDFT1 in TSCC oncogenesis, we carried out MTT, migration, ROS estimation, and flow cytometric cell cycle assays. In addition to the above experiments, we also carried out flow cytometric apoptosis assay, chromatin condensation, γ-H2AX accumulation, and phalloidin staining assays upon overexpression and silencing of piRNA to unveil its mechanism of actions in TSCC malignancy.

KEY FINDINGS

FDFT1 promotes the oncogenesis of TSCC cells. Further, transient overexpression of piR-39980 significantly inhibited proliferation, migration, ROS generation, and colony formation and increased DNA damage and chromatin condensation causing cell death by repressing FDFT1. We conjectured that FDFT1 repression induces hypoxia, which slows DNA repair and accumulates damaged DNA, causing death of TSCC cells.

SIGNIFICANCE

Our study showed FDFT1 acts as an oncogene in TSCC, unlike other cancers, whose repression by a piRNA could prevent oncogenesis by regulating proliferation and apoptosis through hypoxia. This study reveals novel gene-regulatory mechanistic insights into TSCC oncogenesis.

Non-Coding RNAs in Oral Cancer: Emerging Roles and Clinical Applications

Oral cancer (OC) is among the most prevalent cancers in the world. Certain geographical areas are disproportionately affected by OC cases due to the regional differences in dietary habits, tobacco and alcohol consumption. However, conventional therapeutic methods do not yield satisfying treatment outcomes. Thus, there is an urgent need to understand the disease process and to develop diagnostic and therapeutic strategies for OC. In this review, we discuss the role of various types of ncRNAs in OC, and their promising clinical implications as prognostic or diagnostic markers and therapeutic targets. MicroRNA (miRNA), long ncRNA (lncRNA), circular RNA (circRNA), PIWI-interacting RNA (piRNA), and small nucleolar RNA (snoRNA) are the major ncRNA types whose involvement in OC are emerging. Dysregulated expression of ncRNAs, particularly miRNAs, lncRNAs, and circRNAs, are linked with the initiation, progression, as well as therapy resistance of OC via modulation in a series of cellular pathways through epigenetic, transcriptional, post-transcriptional, and translational modifications. Differential expressions of miRNAs and lncRNAs in blood, saliva or extracellular vesicles have indicated potential diagnostic and prognostic importance. In this review, we have summarized all the promising aspects of ncRNAs in the management of OC.

Dysregulation and implications of lncRNAs and miRNAs in oral tongue squamous cell carcinoma: In reply with emphasis on the role of ceRNAs

Increasing evidence indicates that long noncoding RNAs (lncRNAs) as competing endogenous RNAs (ceRNAs) competitively sequestering microRNAs (miRNAs) participate in biological processes of oral tongue squamous cell carcinoma (TSCC). In this Letter, the ceRNA regulatory networks consisting of lncRNA/miRNA/mRNA axes in TSCC were summarized. Dysregulated profiles containing 33 lncRNAs and 31 miRNAs were identified by cancer-associated phenotypes verification. Almost all the lncRNAs could exert the oncogenic roles to sponge miRNAs and regulate targeting mRNA expression, thereby modulating cell proliferation, cell cycle, apoptosis, invasion, migration, metastasis, epithelial-mesenchymal transition, as well as chemoresistance. Significantly, the implications of functional ceRNAs deactivated in tumor cells contribute to the exploitation of novel diagnostic and therapeutic strategies for TSCC.

Epithelial-mesenchymal transition-related long noncoding RNAs in gastric carcinoma

As an evolutionarily phenotypic conversion program, the epithelial-mesenchymal transition (EMT) has been implicated in tumour deterioration and has facilitated the metastatic ability of cancer cells via enhancing migration and invasion. Gastric cancer (GC) remains a frequently diagnosed non-skin malignancy globally. Most GC-associated mortality can be attributed to metastasis. Recent studies have shown that EMT-related long non-coding RNAs (lncRNAs) play a critical role in GC progression and GC cell motility. In addition, lncRNAs are associated with EMT-related transcription factors and signalling pathways. In the present review, we comprehensively described the EMT-inducing lncRNA molecular mechanisms and functional perspectives of EMT-inducing lncRNAs in GC progression. Taken together, the statements of this review provided a clinical implementation in identifying lncRNAs as potential therapeutic targets for advanced GC.