Knockdown of long non-coding RNA LINC00518 inhibits cervical cancer proliferation and metastasis by modulating JAK/STAT3 signaling

Defining new biomarkers for overcoming therapeutical resistance in cervical cancer using lncRNA

Despite improvements in cervical cancer diagnosis and treatment, the prognosis for cervical cancer patients remains dismal due to the development of drug resistance, metastasis, and invasion resulting leading to treatment failure. Long non-coding RNAs (lncRNAs), a class of RNA transcripts have been reported in mediating carcinogenesis as well as drug, and radio-resistance in tumor cells. These lncRNAs regulate various cancer hallmarks and contribute to the development of therapeutic resistance. They regulates multiple signalling pathways, recruits polycomb group, function as miRNA sponge and scaffolds. Additionally, lncRNAs can act as oncogenes or tumor suppressors in cervical cancer. This comprehensive review outlines the biogenesis of lncRNA and its role in cancer development. It delves into the mechanisms through which various lncRNAs mediate chemoresistance and radioresistance in cervical cancer. By shedding into the light of mechanism, this review will also aids researchers in understanding lncRNAs as biomarkers and latest advancements in clinically targeting them with the help of Artificial Intelligence for overcoming chemoresistance and radioresistance, thereby improving cervical cancer treatment.

Value of non-coding RNAs to assess lymph node status in cervical cancer

Cervical cancer (CC) is the fourth cancer in women and is the leading cause of cancer death in 42 countries. Lymph node metastasis is a determinant prognostic factor, as underlined in the latest FIGO classification. However, assessment of lymph node status remains difficult, despite the progress of imaging such as PET-CT and MRI. In the specific setting of CC, all data underlined the need for new biomarkers easily available to assess lymph node status. Previous studies have underlined the potential value of ncRNA expression in gynecological cancers. In this review, we aimed to evaluate the contribution of ncRNAs in tissue and biofluid samples to determine lymph node status in CC with potential impact on both surgical and adjuvant therapies. In tissue samples, our analysis found that there are arguments to support the role of ncRNAs in physiopathology, differential diagnosis from normal tissue, preinvasive and invasive tumors. In biofluids, despite small studies especially concerning miRNAs expression, promising data opens up new avenue to establish a non-invasive signature for lymph node status as well as a tool to predict response to neo- and adjuvant therapies, thus improving management algorithm of patients with CC.

Development and validation of a ferroptosis-related lncRNAs signature to predict prognosis and microenvironment for melanoma

Ferroptosis plays an important role in cancer. However, studies about ferroptosis-related lncRNAs (FRLs) in skin cutaneous melanoma (SKCM) are scarce. Moreover, the relationship between prognostic FRLs and tumor microenvironment (TME) in melanoma remains unclear. This study investigates the potential prognostic value of FRLs and their association with TME in SKCM. The RNA-sequencing data of SKCM were downloaded from The Cancer Genome Atlas (TCGA) database. Melanoma patients were randomly divided into training and testing groups in a 1:1 ratio. A signature composed of 19 FRLs was developed by the least absolute shrinkage and selection operator (LASSO) regression analysis to divide patients into a low-risk group with a better prognosis and a high-risk group with a poor prognosis. Multivariate Cox regression analysis suggested that the risk score was an independent prognostic factor. The Area Under Curve (AUC) value of the risk score reached 0.768 in the training group and 0.770 in the testing group. Subsequent analysis proved that immune-related signaling pathways were significantly enriched in the low-risk group. The tumor immune cell infiltration analysis demonstrated that melanoma in the high-risk group tended to be immunologically "cold". We identified a novel FRLs signature which could accurately predict the prognosis of patients with melanoma.

LINC00518 Promotes Cell Malignant Behaviors via Influencing EIF4A3-Mediated mRNA Stability of MITF in Melanoma

Melanoma has become the most severe sort of skin cancer, deriving from the pigment-producing melanocytes. Existing research has validated that long noncoding RNAs (lncRNAs) have critical function in the progression of cancers. LINC00518 has been studied in cutaneous melanoma; however, the molecular mechanism of LINC00518 in melanoma needs in-depth investigation. In our study, LINC00518 was revealed to be upregulated in melanoma tissues and cells, and melanoma patients in high LINC00518 expression group had poorer prognosis as depicted in GEPIA database. Functional assays revealed that LINC00518 depletion inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT). Furthermore, MITF was confirmed to be upregulated in melanoma tissues and cells, and melanoma patients in high MITF expression group had poorer prognosis as displayed in GEPIA database. MITF expression was positively connected to LINC00518 expression. Additionally, results of mechanism assays uncovered EIF4A3 could bind with LINC00518 and MITF, and LINC00518 recruited EIF4A3 to stabilize MITF mRNA. Finally, it was demonstrated that upregulation of MITF could partially abrogate the inhibitory impact of LINC00518 knockdown on melanoma cell malignant behaviors. To summarize, LINC00518 promotes the malignant processes of melanoma cells through targeting EIF4A3/MITF axis, which might provide novel potential biomarkers for melanoma prognosis.

The Biological Significance of Long noncoding RNAs Dysregulation and their Mechanism of Regulating Signaling Pathways in Cervical Cancer

Despite the remarkable decrease in cervical cancer incidence due to the availability of the HPV vaccine and implementation of screening programs for early detection in developed countries, this cancer remains a major health problem globally, especially in developing countries where most of the cases and mortality occur. Therefore, more understanding of molecular mechanisms of cervical cancer development might lead to the discovery of more effective diagnosis and treatment options. Research on long noncoding RNAs (lncRNAs) demonstrates the important roles of these molecules in many physiological processes and diseases, especially cancer. In the present review, we discussed the significance of lncRNAs altered expression in cervical cancer, highlighting their roles in regulating highly conserved signaling pathways, such as mitogen-activated protein kinase (MAPK), Wnt/β-catenin, Notch, and phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathways and their association with the progression of cervical cancer in order to bring more insight and understanding of this disease and their potential implications in cancer diagnosis and therapy.

Silencing of ITGB6 inhibits the progression of cervical carcinoma via regulating JAK/STAT3 signaling pathway

Background

Integrin β6 (ITGB6), a key submonomer of integrin αvβ6, plays an important role in epithelial-to-mesenchymal transition (EMT), wound healing, epithelial-derived tumor growth, fibrosis, and epithelial repair. However, the role of ITGB6 in cervical carcinoma (CC) remains elusive.

Methods

The expression levels of ITGB6 in CC tissues and cell lines were determined using quantitative real-time polymerase chain reaction (qRT-PCR). The cell viability, proliferation, apoptosis, migration, and invasion were evaluated by Cell Counting Kit-8 (CCK-8), colony-forming, flow cytometry, and Transwell assay, respectively. The expression of related proteins, including EMT markers and the Janus kinase/signal transducer and activator of transcription (JAK/STAT3) signaling markers, were detected using western blotting.

Results

The ITGB6 expression in CC tissues and cells (C-33A, Hela, SiHa, and Caski) was remarkably higher than that in paracarcinoma tissues and ECT1/E6E7 cells. The data from The Cancer Genome Atlas (TCGA) data set suggested that patients with CC with high ITGB6 expression showed poorer overall survival (OS). Compared with the empty transfection group (si-NC), si-ITGB6 restrained the proliferation, migration, and invasion of SiHa and Hela cells, while promoting cell apoptosis. si-ITGB6 suppression decreased the expression of Snail, vimentin, and N-cadherin, while increasing E-cadherin expression. Further research showed that si-ITGB6 reduced p-JAK1/JAK1, p-JAK2/JAK2, and p-STAT3/STAT3 expression in the JAK/STAT3 signaling pathway. Interestingly, proliferation, migration, invasion, and the expressions of the molecular markers of the JAK/STAT3 signaling pathway and EMT pathway induced by ITGB6 were altered by RO8191 (JAK/STAT3 pathway activator). Furthermore, the protein expression levels of Snail, vimentin, N-cadherin, p-STAT3/STAT3, p-JAK1/JAK1, and p-JAK2/JAK2 in tumor tissues were higher than those in adjacent normal tissue, while the expression level of E-cadherin was downregulated in tumor tissues.

Conclusions

Silencing of ITGB6 restrains cell proliferation, migration and invasion, and promotes apoptosis in CC by inhibiting JAK/STAT signaling pathways. Thus, ITGB6 may perhaps be a new and useful candidate target for treating CC.

Long noncoding RNA LINC00518 induces radioresistance by regulating glycolysis through an miR-33a-3p/HIF-1α negative feedback loop in melanoma

The long noncoding RNA, LINC00518, is highly expressed in various types of cancers and is involved in cancer progression. Although LINC00518 promotes the metastasis of cutaneous malignant melanoma (CMM), the mechanism underlaying its effects on CMM radiosensitivity remains unclear. In this study, LINC00518 expression was significantly upregulated in CMM samples, and LINC00518 levels were associated with poor prognosis of patients with CMM. Knockdown of LINC00518 in CMM cells significantly inhibited cell invasion, migration, proliferation, and clonogenicity. LINC00518-mediated invasion, migration, proliferation, and clonogenicity were negatively regulated by the microRNA, miR-33a-3p, in vitro, which increased sensitivity to radiotherapy via inhibition of the hypoxia-inducible factor 1α (HIF-1α)/lactate dehydrogenase A glycolysis axis. Additionally, HIF-1α recognized the miR-33a-3p promoter region and recruited histone deacetylase 2, which decreased the expression of miR-33a-3p and formed an LINC00518/miR-33a-3p/HIF-1α negative feedback loop. Furthermore, signaling with initially activated glycolysis and radioresistance in CMM cells was impaired by Santacruzamate A, a histone deacetylase inhibitor, and 2-deoxy-D-glucose, a glycolytic inhibitor. Lastly, knockdown of LINC00518 expression sensitized CMM cancer cells to radiotherapy in an in vivo subcutaneously implanted tumor model. In conclusion, LINC00518 was confirmed to be an oncogene in CMM, which induces radioresistance by regulating glycolysis through an miR-33a-3p/HIF-1α negative feedback loop. Our study, may provide a potential strategy to improve the treatment outcome of radiotherapy in CMM.

LncRNA LINC00518 Acts as an Oncogene in Uveal Melanoma by Regulating an RNA-Based Network

Simple Summary

Uveal melanoma (UM) is the most frequent primary tumor of the eye in adults. Although molecular alterations on protein-coding genes have been associated with the development of UM, the role of non-coding RNAs and their competitive endogenous networks remain poorly investigated. Starting from a computational analysis on UM expression dataset deposited in The Cancer Genome Atlas, we identified the long non-coding RNA LINC00518 as a potential oncogene. We then experimentally evaluated LINC00518 and its supposed RNA signaling in human biopsies and in vitro functional assays. The results obtained suggest that LINC00518, under potential transcriptional control by MITF, regulates an RNA–RNA network promoting cancer-related processes (i.e., cell proliferation and migration). These findings open the way to the characterization of the unknown RNA signaling associated with UM and pave the way to the exploitation of a potential target for RNA-based therapeutics.

Abstract

Uveal melanoma (UM) is the most common primary intraocular malignant tumor in adults; little is known about the contribution of non-coding RNAs (ncRNAs) to UM pathogenesis. Competitive endogenous RNA (ceRNA) networks based on RNA–RNA interactions regulate physiological and pathological processes. Through a combined approach of in silico and experimental biology, we investigated the expression of a set of long non-coding RNAs (lncRNAs) in patient biopsies, identifying LINC00518 as a potential oncogene in UM. The detection of LINC00518 dysregulation associated with several in vitro functional assays allowed us to investigate its ceRNA regulatory network and shed light on its potential involvement in cancer-related processes, such as epithelial to mesenchymal transition (EMT) and CoCl₂-induced hypoxia-like response. In vitro transient silencing of LINC00518 impaired cell proliferation and migration, and affected mRNA expression of LINGO2, NFIA, OTUD7B, SEC22C, and VAMP3. A “miRNA sponge” and “miRNA protector” model have been hypothesized for LINC00518-induced regulation of mRNAs. In vitro inhibition of MITF suggested its role as a potential activator of LINC00518 expression. Comprehensively, LINC00518 may be considered a new oncogene in UM and a potential target for RNA-based therapeutic approaches.

LINC00518 Interference Inhibits Non-Small Cell Lung Cancer by Upregulating miR216b-5p Expression

Introduction

Non–small cell lung cancer (NSCLC) accounts for the majority of lung cancer cases, and effective treatment for this disease is still lacking. This study aimed to explore the potential role of LINC00518 and miR216b-5p on cell proliferation and tumor growth in NSCLC.

Methods

The expression of LINC00518, miR216b-5p, MMP7, and MMP9 in NSCLC cell lines was determined by RT-qPCR analysis, which was also used to confirm the transfection effects. After transfection, proliferation, clone-formation ability, migration, and invasion of NSCLC cells were detected by CCK8, clone-formation, wound-healing, and transwell assays, respectively. Western blot analysis was used to detect the expression of MMP7, MMP9, Ki67, and PCNA. A xenograft model was constructed by subcutaneous injection of transfected NSCLC cells into nude mice.

Results

The results indicated that LINC00518 expression was increased and miR216b-5p expression decreased in NSCLC cell lines, and A549 cells were chosen for the next experiments. LINC00518 interference inhibited proliferation, invasion, and migration of A549 cells, together with the progression of NSCLC in vivo. In addition, LINC00518 directly targeted miR216b-5p. Downregulation of miR216b-5p weakened the inhibitory effect of LINC00518 interference on proliferation, invasion, and migration of A549 cells, as well as progression of NSCLC in vivo.

Discussion

In conclusion, LINC00518 interference inhibits NSCLC, which is partially reversed by downregulation of miR216b-5p expression.

Resveratrol suppresses the growth and metastatic potential of cervical cancer by inhibiting STAT3Tyr705 phosphorylation

Aberrant signal transducer and activator of transcription 3 (STAT3) signaling promotes the initiation and progression of cancer in humans by either inhibiting apoptosis or inducing cell proliferation, angiogenesis, invasion, and metastasis. The role of resveratrol（RES）in inhibiting the STAT3 signaling pathway in vivo, particularly in cervical cancer is still unknown. This study aims to investigate the role of STAT3 and its phosphorylation in RES‐mediated suppression of cervical cancer. The effects of RES on cervical cancer were determined by examining tumor tissues, their histological changes, and the volume and weight of tumor tissues grown from HeLa cells injected in female athymic BALB/C nude mice. The structure and target interaction of RES were virtually screened using the molecular docking program Autodock Vina. The status of phosphorylated STAT3, protein levels of epithelial‐mesenchymal transition molecular markers and extracellular matrix degradation enzymes were determined through Western blot. We demonstrated that RES could suppress the proliferation and metastatic potential of cervical cancer cells by inactivating phosphorylation of STAT3 at Tyr705 but not Ser727. This effect was intensified by inhibition of the STAT3 signal pathway.

Combined inhibition of JAK1/2 and DNMT1 by newly identified small-molecule compounds synergistically suppresses the survival and proliferation of cervical cancer cells

Despite substantial advances in treating cervical cancer (CC) with surgery, radiation and chemotherapy, patients with advanced CC still have poor prognosis and significantly variable clinical outcomes due to tumor recurrence and metastasis. Therefore, to develop more efficacious and specific treatments for CC remains an unmet clinical need. In this study, by virtual screening the SPECS database, we identified multiple novel JAK inhibitor candidates and validated their antitumor drug efficacies that were particularly high against CC cell lines. AH057, the best JAK inhibitor identified, effectively blocked the JAK/STAT pathways by directly inhibiting JAK1/2 kinase activities, and led to compromised cell proliferation and invasion, increased apoptosis, arrested cell cycles, and impaired tumor progression in vitro and in vivo. Next, by screening the Selleck chemical library, we identified SGI-1027, a DNMT1 inhibitor, as the compound that displayed the highest synergy with AH057. By acting on a same set of downstream effector molecules that are dually controlled by JAK1/2 and DNMT1, the combination of AH057 with SGI-1027 potently and synergistically impaired CC cell propagation via dramatically increasing apoptotic cell death and cell-cycle arrest. These findings establish a preclinical proof of concept for combating CC by dual targeting of JAK1/2 and DNMT1, and provide support for launching a clinical trial to evaluate the efficacy and safety of this drug combination in patients with CC and other malignant tumors.

Long noncoding RNA LINC00518 acts as a competing endogenous RNA to promote the metastasis of malignant melanoma via miR-204-5p/AP1S2 axis

Long intergenic nonprotein coding RNA 518 (LINC00518) has been shown to promote cancer cell growth and metastasis in some human tumors. Although it has been reported that LINC00518 is dysregulated in melanoma, its exact role and molecular mechanism in melanoma remain unclear. RNA-seq analysis and qRT-PCR was used to detect the expression of LINC00518 in melanoma tissues. Melanoma cases from The Cancer Genome Atlas (TCGA), GEO#GSE15605 and GEO#GSE24469 were included in this study. 3D migration, transwell and scratch wound assay were used to explore the role of LINC00518 in melanoma cells. Bioinformatics, luciferase reporter assays, MS2-RIP assay, RNA pull-down assay and RNA-ChIP assay were used to demonstrate the mechanism of LINC00518 in melanoma. We found that LICN00518 was significantly upregulated in melanoma tissue, and high LICN00518 level was an independent risk factor for melanoma patients. LICN00518 promoted the invasion and migration of melanoma cells. LICN00518 exerted its role by decoying miR-204-5p to upregulate Adaptor Related Protein Complex 1 Sigma 2 Subunit (AP1S2) expression. We also demonstrated that LICN00518 promoted melanoma metastasis in vivo through pulmonary metastasis assay. This result elucidates a new mechanism for LICN00518 in the metastasis of melanoma. LICN00518 may serve as a survival indicator and potential therapeutic target in melanoma patients.