MicroRNA-422a functions as a tumor suppressor in non-small cell lung cancer through SULF2-mediated TGF-β/SMAD signaling pathway

6-O-endosulfatases in tumor metastasis: heparan sulfate proteoglycans modification and potential therapeutic targets

Metastasis is the leading cause of cancer-associated mortality. Although advances in the targeted treatment and immunotherapy have improved the management of some cancers, the prognosis of metastatic cancers remains unsatisfied. Therefore, the specific mechanisms in tumor metastasis need further investigation. 6-O-endosulfatases (SULFs), comprising sulfatase1 (SULF1) and sulfatase 2 (SULF2), play pivotal roles in the post-synthetic modifications of heparan sulfate proteoglycans (HSPGs). Consequently, these extracellular enzymes can regulate a variety of downstream pathways by modulating HSPGs function. During the past decades, researchers have detected the expression of SULF1 and SULF2 in most cancers and revealed their roles in tumor progression and metastasis. Herein we reviewed the metastasis steps which SULFs participated in, elucidated the specific roles and mechanisms of SULFs in metastasis process, and discussed the effects of SULFs in different types of cancers. Moreover, we summarized the role of targeting SULFs in combination therapy to treat metastatic cancers, which provided some novel strategies for cancer therapy.

Current landscape of miRNAs and TGF-β signaling in lung cancer progression and therapeutic targets

Lung cancer (LC) is the primary reason for cancer-associated fatalities globally. Due to both tumor-suppressing and tumor-promoting activities, the TGF-β family of growth factors is extremely essential to tumorigenesis. A non-coding single-stranded short RNA called microRNA (miRNA), which is made up of about 22 nt and is encoded by endogenous genes, can control normal and pathological pathways in various kinds of cancer, including LC. Recent research demonstrated that the TGF-β signaling directly can affect the synthesis of miRNAs through suppressor of mothers against decapentaplegic (SMAD)-dependent activity or other unidentified pathways, which could generate allostatic feedback as a result of TGF-β signaling stimulation and ultimately affect the destiny of cancer tissues. In this review, we emphasize the critical functions of miRNAs in lung cancer progression and, more critically, how they affect the TGF-β signaling pathway, and explore the role of both the TGF-β signaling pathway and miRNAs as potential therapeutic targets for improving the treatments of LC patients.

Regulation and therapeutic potentials of microRNAs to non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, accounting for 80%-85% of total cases and leading to millions of deaths worldwide. Drug resistance is the primary cause of treatment failure in NSCLC, which urges scientists to develop advanced approaches for NSCLC treatment. Among novel approaches, the miRNA-based method has emerged as a potential approach as it allows researchers to modulate target gene expression. Subsequently, cell behaviors are altered, which leads to the death and the depletion of cancer cells. It has been reported that miRNAs possess the capacity to regulate multiple genes that are involved in various signaling pathways, including the phosphoinositide 3-kinase, receptor tyrosine kinase/rat sarcoma virus/mitogen-activated protein kinase, wingless/integrated, retinoblastoma, p53, transforming growth factor β, and nuclear factor-kappa B pathways. Dysregulation of these signaling pathways in NSCLC results in abnormal cell proliferation, tissue invasion, and drug resistance while inhibiting apoptosis. Thus, understanding the roles of miRNAs in regulating these signaling pathways may enable the development of novel NSCLC treatment therapies. However, a comprehensive review of potential miRNAs in NSCLC treatment has been lacking. Therefore, this review aims to fill the gap by summarizing the up-to-date information on miRNAs regarding their targets, impact on cancer-associated pathways, and prospective outcomes in treating NSCLC. We also discuss current technologies for delivering miRNAs to the target cells, including virus-based, non-viral, and emerging extracellular vesicle-based delivery systems. This knowledge will support future studies to develop an innovative miRNA-based therapy and select a suitable carrier to treat NSCLC effectively.

Unraveling Therapeutic Opportunities and the Diagnostic Potential of microRNAs for Human Lung Cancer

Lung cancer is a major public health problem and a leading cause of cancer-related deaths worldwide. Despite advances in treatment options, the five-year survival rate for lung cancer patients remains low, emphasizing the urgent need for innovative diagnostic and therapeutic strategies. MicroRNAs (miRNAs) have emerged as potential biomarkers and therapeutic targets for lung cancer due to their crucial roles in regulating cell proliferation, differentiation, and apoptosis. For example, miR-34a and miR-150, once delivered to lung cancer via liposomes or nanoparticles, can inhibit tumor growth by downregulating critical cancer promoting genes. Conversely, miR-21 and miR-155, frequently overexpressed in lung cancer, are associated with increased cell proliferation, invasion, and chemotherapy resistance. In this review, we summarize the current knowledge of the roles of miRNAs in lung carcinogenesis, especially those induced by exposure to environmental pollutants, namely, arsenic and benzopyrene, which account for up to 1/10 of lung cancer cases. We then discuss the recent advances in miRNA-based cancer therapeutics and diagnostics. Such information will provide new insights into lung cancer pathogenesis and innovative diagnostic and therapeutic modalities based on miRNAs.

Significant impact of redox regulation of estrogen-metabolizing proteins on cellular stress responses

The ultimate driving force, stress, promotes adaptability/evolution in proliferating organisms, transforming tumorigenic growth. Estradiol (E2) regulates both phenomena. In this study, bioinformatics-tools, site-directed-mutagenesis (human estrogen-sulfotransferase/hSULT1E1), HepG2 cells tested with N-acetyl-cysteine (NAC/thiol-inducer) or buthionine-sulfoxamine (BSO/thiol-depletory) were evaluated for hSULT1E1 (estradiol-sulphating/inactivating) functions. Reciprocal redox regulation of steroid sulfatase (STS, E2-desulfating/activating) results in the Cys-formylglycine transition by the formylglycine-forming enzyme (FGE). The enzyme sequences and structures were examined across the phylogeny. Motif/domain and the catalytic conserve sequences and protein-surface-topography (CASTp) were investigated. The E2 binding to SULT1E1 suggests that the conserved-catalytic-domain in this enzyme has critical Cysteine 83 at position. This is strongly supported by site-directed mutagenesis/HepG2-cell research. Molecular-docking and superimposition studies of E2 with the SULT1E1 of representative species and to STS reinforce this hypothesis. SULT1E1-STS are reciprocally activated in response to the cellular-redox-environment by the critical Cys of these two enzymes. The importance of E2 in organism/species proliferation and tissue tumorigenesis is highlighted.

Circ_0026134 promotes NSCLC progression by the miR-3619-5p/CHAF1B axis

BACKGROUND

Non-small cell lung cancer (NSCLC) is the leading cause of cancer death worldwide. Circular RNAs (circRNAs) have been implicated in the pathogenesis of NSCLC. In this study, we explored the molecular determinants underlying the oncogenic property of circ_0026134 in NSCLC.

METHODS

The levels of circ_0026134, miR-3619-5p and chromatin assembly factor 1 subunit B axis (CHAF1B) were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Cell colony formation, migration, invasion and apoptosis were detected by colony formation, Transwell, and flow cytometry assays, respectively. Direct relationships among circ_0026134, miR-3619-5p and CHAF1B were verified by dual-luciferase reporter assays.

RESULTS

Our results showed that circ_0026134 was highly expressed in NSCLC tissues and cells. Reduced circ_0026134 expression or miR-3619-5p overexpression inhibited NSCLC cell colony formation, migration, invasion, glycolysis and promoted cell apoptosis in vitro. Moreover, circ_0026134 directly targeted miR-3619-5p, and circ_0026134 regulated CHAF1B expression through miR-3619-5p. CHAF1B was a downstream effector of circ_0026134 in affecting NSCLC cell functional behaviors in vitro. Additionally, circ_0026134 silencing weakened tumor growth in vivo.

CONCLUSIONS

Our study identified a novel regulatory mechanism, the circ_0026134/miR-3619-5p/CHAF1B axis, for the oncogenic role of circ_0026134 in NSCLC, highlighting circ_00261345 inhibition as a potential therapeutic method against NSCLC.

Up-regulation of circ_0000353 impedes the proliferation and metastasis of non-small cell lung cancer cells via adsorbing miR-411-5p and increasing forkhead box O1

BACKGROUND

Non-small cell lung cancer (NSCLC) is the most common malignant tumor worldwide. This work focuses on investigating the role of circ_0000353 in NSCLC and its potential mechanism of action.

METHODS

The expression levels of circ_0000353 and miR-411-5p in NSCLC and their matched normal lung tissues were detected by real-time PCR (RT-PCR). The correlation between the circ_0000353 expression and the clinicopathological parameters of NSCLC patients was also analyzed. CCK-8, BrdU and colony formation assays were adopted to detect the role of circ_0000353 in the proliferation of NSCLC cells. The metastasis of NSCLC cells was measured by Transwell assay. The dual-luciferase reporter gene assay was used to confirm the targeting relationship between circ_0000353 and miR-411-5p. The expression level of FOXO1 was detected by western blot.

RESULTS

Circ_0000353 was significantly down-regulated in NSCLC tissues and cell lines, and the decreased expression was significantly linked to the increased clinical stage, larger tumor volume, and metastasis. The circ_0000353 over-expression restrained the proliferation, migration, and invasion of NSCLC cells in vitro. Additionally, up-regulation of miR-411-5p was observed in NSCLC tissues and cell lines, and luciferase assay and RT-PCR assay showed that circ_0000353 over-expression could target miR-411-5p and suppress its expression. Further studies confirmed that circ_0000353 and miR-411-5p modulated the FOXO1 expression.

CONCLUSION

Circ_0000353 repressed the proliferation, migration, and invasion of NSCLC cells via inhibition of miR-411-5p and up-regulation of FOXO1.

Long Noncoding RNA CCDC26 Promotes Thyroid Cancer Malignant Progression via miR-422a/EZH2/Sirt6 Axis

Purpose

Long noncoding RNAs are crucial regulators in thyroid cancer progression. However, the role of lncRNA CCDC26 in thyroid cancer remains unclear. Here, we aimed to explore the effect of CCDC26 on thyroid cancer progression and the underlying mechanism.

Materials and Methods

A total of 50 clinical thyroid cancer samples were studied in patients' samples, cultured cells, and nude mice before and after treatment using quantitative reverse transcription-PCR, CCK-8 assays, BrdU incorporation assays, Transwell assays, cell apoptosis analysis, luciferase reporter gene assay, RNA immunoprecipitation, Western blot analysis, and tumorigenicity analysis.

Results

CCDC26 expression was elevated in patients' thyroid cancer tissues and thyroid cancer cell lines. CCDC26 depletion remarkably reduced proliferation, invasion, and migration but induced apoptosis of thyroid cancer cells. Mechanically, miR-422a mimic remarkably reduced the luciferase activity of CCDC26 transfected cells but failed to affect cells transfected with CCDC26 containing the mutated miR-422a-binding site. RNA immunoprecipitation (RIP) assays showed that CCDC26 and miR-422a preferentially interacted with Ago2, but not IgG, in the micro-ribonucleoprotein complexes (miRNPs). CCDC26 depletion enhanced miR-422a expression and MiR-422a inhibitor reversed CCDC26 knockdown-induced inhibition of thyroid cancer progression in vitro. CCDC26 upregulated EZH2 and Sirt6 expression by sponging miR-422a in thyroid cancer cells. Tumorigenicity analysis in nude mice revealed that CCDC26 contributed to thyroid tumor growth via miR-422a/EZH2/Sirt6 axis in vivo.

Conclusion

CCDC26 promotes thyroid cancer malignant progression via miR-422a/EZH2/Sirt6 axis. This finding provides new insights into the mechanism by which CCDC26 promotes malignant thyroid cancer development, advances our understanding of lncRNAs' association with thyroid cancer, and indicates that CCDC26 and miR-422a may serve as potential targets for thyroid cancer.

NORAD regulates epithelial‑mesenchymal transition of non‑small cell lung cancer cells via miR‑422a

The poor prognosis of non‑small cell lung cancer (NSCLC) is related to epithelial‑mesenchymal transition (EMT). Recent studies demonstrated that non‑coding RNA activated by DNA damage (NORAD) displays a carcinogenic effect and targets microRNA (miR)‑422a, which may be involved in tumor cell migration and invasion. The aim of the present study was to investigate the effect of NORAD on NSCLC cell EMT and the underlying mechanism. Reverse transcription‑quantitative PCR and western blotting were performed to detect the expression levels of long non‑coding RNAs, miRNAs and mRNAs. Cell viability, migration and invasion were detected by conducting Cell Counting Kit‑8, wound healing and Transwell assays, respectively. The target of NORAD was predicted using starBase and further confirmed by conducting a dual‑luciferase reporter assay. The results indicated that NORAD expression was significantly increased in lung cancer tissues and cells compared with adjacent healthy tissues and cells. Compared with the control groups, NORAD overexpression promoted SK‑MES‑1 cell viability, migration and invasion, whereas NORAD knockdown resulted in the opposite effects in A549 cells. Moreover, miR‑422a, which was predicted to be a target of NORAD, displayed lower expression levels in lung cancer tissues compared with adjacent healthy tissues. In addition, miR‑422a overexpression partially reversed NORAD overexpression‑induced increases in SK‑MES‑1 cell viability, migration, invasion and EMT. In addition, miR‑422a knockdown partially reversed the effects of NORAD knockdown. The present study suggested that NORAD regulated lung cancer cell EMT by regulating the expression of miR‑422a, providing a potential therapeutic target for the intervention of the development of NSCLC.

Overexpression of P4HA1 Is Correlated with Poor Survival and Immune Infiltrates in Lung Adenocarcinoma

Lung adenocarcinoma (LUAD) is a major pathological type of lung cancer. Understanding the mechanism of LUAD at the molecular level is important for a clinical decision. In this study, we use bioinformatic analysis to explore the prognostic value of P4HA1 in lung adenocarcinoma (LUAD) and the relationship with prognosis and tumor-infiltrating immune cells (TIICs). The results showed that the expression of P4HA1 was significantly higher in tumor tissues than in normal tissues for LUAD patients. Upregulated P4HA1 was related to stage and T classification. Kaplan-Meier analysis indicated that upregulation of P4HA1 was significantly related to worse overall survival (OS). Univariate and multivariate Cox analysis indicated P4HA1 remained to be an independent prognostic factor. GSEA showed that several cancer-related and immune-related signaling pathways exhibited prominently differential enrichment in P4HA1-high expression phenotype. In addition, the expression of P4HA1 was significantly correlated with proportion of several TIICs, particularly B cells and CD4+ T cells. In conclusion, our study confirmed that P4HA1 is a promising biomarker of poor prognosis and relates to immune infiltrates in LUAD.

MicroRNA‑422a functions as a tumor suppressor in glioma by regulating the Wnt/β‑catenin signaling pathway via RPN2

MicroRNAs (miRs), which act as crucial regulators of oncogenes and tumor suppressors, have been confirmed to play a significant role in the initiation and progression of various malignancies, including glioma. The present study analyzed the expression and roles of miR‑422a in glioma, and reverse transcription‑quantitative PCR confirmed that miR‑422a expression was significantly lower in glioblastoma multiforme (GBM) samples and cell lines compared with the low‑grade glioma samples and the H4 cell line, respectively. miR‑422a overexpression suppressed proliferation and invasion, and induced apoptosis in LN229 and U87 cell lines. Luciferase reporter assay, western blotting and RNA immunoprecipitation analysis revealed that ribophorin II (RPN2) is a direct functional target of miR‑422a. Additionally, the overexpression of RPN2 partially reversed the miR‑422a‑mediated inhibitory effect on the malignant phenotype. Mechanistic investigation demonstrated that the upregulation of miR‑422a inhibited β‑catenin/transcription factor 4 transcriptional activity, at least partially through RPN2, as indicated by in vitro and in vivo experiments. Furthermore, RPN2 expression was inversely correlated with miR‑422a expression in GBM specimens and predicted patient survival in the Chinese Glioma Genome Atlas, UALCAN, Gene Expression Profiling Interactive Analysis databases. In conclusion, the present data reveal a new miR‑422a/RPN2/Wnt/β‑catenin signaling axis that plays critical roles in glioma tumorigenesis, and it represents a potential therapeutic target for GBM.

Hypoxia-induced miR-3677-3p promotes the proliferation, migration and invasion of hepatocellular carcinoma cells by suppressing SIRT5

Hepatocellular carcinoma (HCC), with life‐threatening malignant behaviours, often develops distant metastases and is the fourth most common primary cancer in the world, having taken millions of lives in Asian countries such as China. The novel miR‐3677‐3p is involved in a high‐expression‐related poor prognosis in HCC tissues and cell lines, indicating oncogenesis functions in vitro and in vivo. Initially, we confirmed the inhibition of proliferation, migration and invasion in miR‐3677‐3p knock‐down MHCC‐97H and SMMC‐7721 cell lines, which are well known for their high degree of invasiveness. Then, we reversed the functional experiments in the low‐miR‐3677‐3p‐expression Hep3B cell line via overexpressing miR‐3677‐3p. In nude mice xenograft and lung metastasis assays, we found suppressor behaviours, smaller nodules and low density of organ spread, after injection of cells transfected with shRNA‐miR‐3677‐3p. A combination of databases (Starbase, TargetScan and MiRgator) illustrated miR‐3677‐3p targets, and it was shown to suppress the expression of SIRT5 in a dual‐luciferase reporter system. To clarify the conclusions of previous ambiguous research, we up‐regulated SIRT5 in Hep3B cells, and rescue tests were established for confirmation that miR‐3677‐3p suppresses SIRT5 to enhance the migration and invasion of HCC. Interestingly, we discovered hypoxia‐induced miR‐3677‐3p up‐regulation benefited HCC malignancy and invasiveness. In conclusion, the overexpression of miR‐3677‐3p mediated SIRT5 inhibition, which could increase proliferation, migration and invasion of HCC in hypoxic microenvironments.

miR-365b regulates the development of non-small cell lung cancer via GALNT4

Non-small cell lung cancer (NSCLC) is a type of cancer that is associated with high prevalence and high mortality rates in China. Therefore, it is of importance to identify the mechanisms underlying NSCLC progression. In the present study, reverse transcription-quantitative PCR was performed to measure the expression of microRNA (miR)-365b in NSCLC cell lines. In addition, the biological roles of miR-365b and N-acetylgalactosaminyltransferase 4 (GALNT4) were investigated by manipulating the expression levels of miR-365b and GALNT4 in NSCLC cells. It was found that miR-365b expression was reduced in NSCLC tissues and cells. Overexpression of miR-365b inhibited NSCLC cell proliferation whilst promoting apoptosis, but miR-365b knockdown promoted NSCLC cell proliferation. In addition, it was demonstrated that miR-365b regulated the proliferation and apoptosis of NSCLC cells by targeting GALNT4 expression. Collectively, the present study identified a miR-365b/GALNT4 regulatory axis in NSCLC, suggesting that miR-365b may serve as a therapeutic target for NSCLC.

The Effect of NNK, A Tobacco Smoke Carcinogen, on the miRNA and Mismatch DNA Repair Expression Profiles in Lung and Head and Neck Squamous Cancer Cells

Tobacco smoking is a common risk factor for lung cancer and head and neck cancer. Molecular changes such as deregulation of miRNA expression have been linked to tobacco smoking in both types of cancer. Dysfunction of the Mismatch DNA repair (MMR) mechanism has also been associated with a poor prognosis of these cancers, while a cross-talk between specific miRNAs and MMR genes has been previously proposed. We hypothesized that exposure of lung and head and neck squamous cancer cells (NCI and FaDu, respectively) to tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is capable of altering the expression of MSH2 and MLH1, key MMR components, by promoting specific miRNA deregulation. We found that either a low (1 μM) or high (2 μM) dose of NNK induced significant upregulation of "oncomirs" miR-21 and miR-155 and downregulation of "tumor suppressor" miR-422a, as well as the reduction of MMR protein and mRNA expression, in NCI and FaDu, compared to controls. Inhibition of miR-21 restored the NNK-induced reduced MSH2 phenotype in both NCI and FaDu, indicating that miR-21 might contribute to MSH2 regulation. Finally, NNK exposure increased NCI and FaDu survival, promoting cancer cell progression. We provide novel findings that deregulated miR-21, miR-155, and miR-422a and MMR gene expression patterns may be valuable biomarkers for lung and head and neck squamous cell cancer progression in smokers.

MiRNAs and LncRNAs: Dual Roles in TGF-β Signaling-Regulated Metastasis in Lung Cancer

Lung cancer is one of the most malignant cancers around the world, with high morbidity and mortality. Metastasis is the leading cause of lung cancer deaths and treatment failure. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs), two groups of small non-coding RNAs (nc-RNAs), are confirmed to be lung cancer oncogenes or suppressors. Transforming growth factor-β (TGF-β) critically regulates lung cancer metastasis. In this review, we summarize the dual roles of miRNAs and lncRNAs in TGF-β signaling-regulated lung cancer epithelial-mesenchymal transition (EMT), invasion, migration, stemness, and metastasis. In addition, lncRNAs, competing endogenous RNAs (ceRNAs), and circular RNAs (circRNAs) can act as miRNA sponges to suppress miRNAs, thereby mediating TGF-β signaling-regulated lung cancer invasion, migration, and metastasis. Through this review, we hope to cast light on the regulatory mechanisms of miRNAs and lncRNAs in TGF-β signaling-regulated lung cancer metastasis and provide new insights for lung cancer treatment.

MicroRNA-1298 is downregulated in non-small cell lung cancer and suppresses tumor progression in tumor cells

BACKGROUND

MicroRNAs (miRNAs) have been reported to serve pivotal roles in tumorigenesis. This study sough to assess the expression and clinical significance of microRNA-1298 (miR-1298) in patients with non-small cell lung cancer (NSCLC), and explore the functional role of miR-1298 in tumorigenesis.

METHODS

One hundred and twenty-one NSCLC patients were recruited in this study. The expression of miR-1298 was estimated using quantitative real-time PCR. Kaplan-Meier survival curves and Cox regression analysis were used to evaluate the prognostic value of miR-1298. Gain- and loss-of-function experiments were preformed to explore the biological function of miR-1298 in NSCLC cells.

RESULTS

Expression levels of miR-1298 were downregulated in NSCLC tissues and cells compared with the corresponding normal controls. The decreased expression of miR-1298 was associated with patients' lymph node metastasis and TNM stage. The low expression of miR-1298 predicted poor overall survival and served as an independent prognostic indicator in NSCLC patients. According to the cell experiments, NSCLC cell proliferation, migration and invasion were inhibited by the overexpression of miR-1298.

CONCLUSION

All the data indicated that the downregulation of miR-1298 predicts poor prognosis of NSCLC, and the overexpression of miR-1298 in NSCLC cells leads to inhibited tumorigenesis. The aberrant miR-1298 may serve as a novel biomarker and therapeutic target in NSCLC.