miR-639 Expression Is Silenced by DNMT3A-Mediated Hypermethylation and Functions as a Tumor Suppressor in Liver Cancer Cells

Sensitivity of renal cell carcinoma to cuproptosis: a bioinformatics analysis and experimental verification

Purpose: Targeting cuproptosis is considered as a promising therapeutic strategy for the prevention of tumors. However, the potential role of cuproptosis and its related genes in clear cell renal cell carcinoma (ccRCC) remains elusive. The present study aims to explore the sensitivity of ccRCC to cuproptosis and its underlying mechanism. Methods: Cuproptosis differential genes (CDGs) were extracted using the GSE53757 and GSE66272 datasets. A comprehensive analysis of the role of CDGs was conducted through multiple public databases and experiments. Results: It was found that cuproptosis inducer elesclomol significantly induced cell death in 786-O and A498 cells. FDX and DLAT exhibited significantly low expression, which were independent prognostic factors for poor survival, and had a strong positive correlation in ccRCC patients. Functional analysis of differentially expressed genes positively or negatively correlated with both FDX1 and DLAT indicated that acetyl-CoA biosynthetic process and acetyl-CoA metabolic process were remarkably affected. In ccRCC patients, the methylation levels and sites of FDX1 and DLAT genes were dramatically correlated with overall survival (OS). The expressions of FDX1 and DLAT were closely related to immune infiltration and immune checkpoints. Docking results indicated that mitotane, adicicol and dihydrolipoic acid might be potential drug targets for FDX1 and DLAT. Conclusions: Overall, the present study demonstrates the sensitivity of ccRCC to cuproptosis, and targeting the combination of FDX1 and DLAT may be a novel therapeutic strategy to induce cuproptosis in ccRCC.

A A, Suchita J, Gacche RN. Cancer metastases: Tailoring the targets

Metastasis is an intricate and formidable pathophysiological process encompassing the dissemination of cancer cells from the primary tumour body to distant organs. It stands as a profound and devastating phenomenon that constitutes the primary driver of cancer-related mortality. Despite great strides of advancements in cancer research and treatment, tailored anti-metastasis therapies are either lacking or have shown limited success, necessitating a deeper understanding of the intrinsic elements driving cancer invasiveness. This comprehensive review presents a contemporary elucidation of pivotal facets within the realm of cancer metastasis, commencing with the intricate processes of homing and invasion. The process of angiogenesis, which supports tumour growth and metastasis, is addressed, along with the pre-metastatic niche, wherein the primary tumour prepares for a favorable microenvironment at distant sites for subsequent metastatic colonization. The landscape of metastasis-related genetic and epigenetic mechanisms, involvement of metastasis genes and metastasis suppressor genes, and microRNAs (miRNA) are also discussed. Furthermore, immune modulators' impact on metastasis and their potential as therapeutic targets are addressed. The interplay between cancer cells and the immune system, including immune evasion mechanisms employed by metastatic cells, is discussed, highlighting the importance of targeting immune modulation in arresting metastatic progression. Finally, this review presents promising treatment opportunities derived from the insights gained into the mechanisms of metastasis. Identifying novel therapeutic targets and developing innovative strategies to disrupt the metastatic cascade holds excellent potential for improving patient outcomes and ultimately reducing cancer-related mortality.

NOTCH3 as a prognostic biomarker and its correlation with immune infiltration in gastrointestinal cancers

NOTCH receptor 3 (NOTCH3) is known to regulate the transcription of oncogenes or tumor suppressor genes, thereby playing a crucial role in tumor development, invasion, maintenance, and chemotherapy resistance. However, the specific mechanism of how NOTCH3 drives immune infiltration in gastrointestinal cancer remains uncertain. The expression of NOTCH3 was analyzed through Western blot, PCR, Oncomine database, and the Tumor Immune Estimation Resource (TIMER) site. Kaplan-Meier plotter, PrognoScan database, and gene expression profile interactive analysis (GEPIA) were used to assess the impact of NOTCH3 on clinical prognosis. The correlation between NOTCH3 expression and immune infiltration gene markers was investigated using TIMER and GEPIA. NOTCH3 was found to be commonly overexpressed in various types of gastrointestinal tumors and was significantly associated with poor prognosis. Furthermore, the expression level of NOTCH3 showed a significant correlation with the tumor purity of gastrointestinal tumors and the extent of immune infiltration by different immune cells. Our findings suggest that NOTCH3 may act as a crucial regulator of tumor immune cell infiltration and can serve as a valuable prognostic biomarker in gastrointestinal cancers.

Bioinformatics and Expression Analyses of miR-639, miR-641, miR-1915-3p and miR-3613-3p in Colorectal Cancer Pathogenesis

Objectives: MicroRNAs (miRNAs) have important function in cancer development and progression. This study aims to determine the expression levels of miR-639, miR-641, miR-1915-3p, and miR-3613-3p in tissues of colorectal cancer (CRC) patients and the role of these miRNAs in the CRC pathogenesis. Methods: Tumor and non-tumor tissues were collected from a total of 59 CRC patients. qRT-PCR was used to identify the expressions of miR-639, miR-641, miR-1915-3p and miR-3613-3p. Through bioinformatics analysis, the target genes of miRNAs were identified by using DIANA mirPath v.3. Signaling pathways were generated using KEGG pathway database. Biological pathway, cellular component analysis, and analysis of Protein-Protein Interactions (PPI) Networks were performed using FunRich and STRING database. Results: Our findings revealed that miR-639, miR-641 and miR-3613-3p were significantly downregulated, and miR-1915-3p was significantly upregulated in tumor tissues compared to non-tumor tissues (p˂0.05). Furthermore, MAPK signaling pathway was the most enriched KEGG pathway regulated by miR-639, miR-641, miR-1915-3p and miR-3613-p. According to the FunRich, it was demonstrated that the targeted genes by miRNAs related to the cellular component and biological pathways such as beta-catenin-TCF7L2, axin-APC-beta-catenin-GSK3B complexes, Arf6 signaling, Class I PI3K signaling, etc. And, by the PPI analysis, it was established that the target genes were clustered on CTNNB1 and KRAS. Conclusions: These outcomes imply that miR-639, miR-641 and miR-3613-3p have tumor suppressor roles, while miR-1915-3p has an oncogenic role in the pathogenesis of CRC. According to the results of the current study, dysregulated miR-639, miR-641, miR-1915-3p, and miR-3613-3p might contribute to the development of CRC.

Hsa_circ_0084003 modulates glycolysis and epithelial-mesenchymal transition in pancreatic ductal adenocarcinoma through targeting hsa-miR-143-3p/DNMT3A axis

Pancreatic ductal adenocarcinoma, one of the deadliest tumors of the digestive tract, is a difficult and invasive malignancy. Current treatment for pancreatic ductal adenocarcinoma mainly depends on surgery combined with radiotherapy and chemotherapy, which, however, often resulting in questionable curative effect. Therefore, new targeted therapies are needed in future treatment. We first interfered with hsa_circ_0084003 expression in pancreatic ductal adenocarcinoma cells, and further studied how hsa_circ_0084003 functioned in regulating pancreatic ductal adenocarcinoma cell aerobic glycolysis and epithelial-mesenchymal transition, and also evaluated the regulatingeffect of hsa_circ_0084003 on hsa-miR-143-3p and its target DNA methyltransferase 3A. Hsa_circ_0084003 knockdown could notably inhibit the aerobic glycolysis and epithelial-mesenchymal transition of pancreatic ductal adenocarcinoma cells. Mechanistically, hsa_circ_0084003 could regulate its downstream target DNA methyltransferase 3A by binding to hsa-miR-143-3p, and overexpression of hsa_circ_0084003 could reverse the anticarcinogenic effect of hsa-miR-143-3p on aerobic glycolysis and epithelial-mesenchymal transition in pancreatic ductal adenocarcinoma cells. Hsa_circ_0084003, as a carcinogenic circular RNA, regulated its downstream target DNA methyltransferase 3A to promote pancreatic ductal adenocarcinoma cell aerobic glycolysis and epithelial-mesenchymal transition through sponging hsa-miR-143-3p. Therefore, hsa_circ_0084003 could be studied as a possible therapeutic target regarding pancreatic ductal adenocarcinoma.

Promoter methylation-regulated miR-148a-3p inhibits lung adenocarcinoma (LUAD) progression by targeting MAP3K9

Lung adenocarcinoma (LUAD) characterized by high metastasis and mortality is the leading subtype of non-small cell lung cancer. Evidence shows that some microRNAs (miRNAs) may act as oncogenes or tumor suppressor genes, leading to malignant tumor occurrence and progression. To better understand the molecular mechanism associated with miRNA methylation in LUAD progression and clinical outcomes, we investigated the correlation between miR-148a-3p methylation and the clinical features of LUAD. In the LUAD cell lines and tumor tissues from patients, miR-148a-3p was found to be significantly downregulated, while the methylation of miR-148a-3p promoter was notably increased. Importantly, miR-148a-3p hypermethylation was closely associated with lymph node metastasis. We demonstrated that mitogen-activated protein (MAP) kinase kinase kinase 9 (MAP3K9) was the target of miR-148a-3p and that MAP3K9 levels were significantly increased in both LUAD cell lines and clinical tumor tissues. In A549 and NCI-H1299 cells, overexpression of miR-148a-3p or silencing MAP3K9 significantly inhibited cell growth, migration, invasion and cytoskeleton reorganization accompanied by suppressing the epithelial-mesenchymal transition. In a nude mouse xenograft assay we found that tumor growth was effectively inhibited by miR-148a-3p overexpression. Taken together, the promoter methylation-associated decrease in miR-148a-3p could lead to lung cancer metastasis by targeting MAP3K9. This study suggests that miR-148a-3p and MAP3K9 may act as novel therapeutic targets for the treatment of LUAD and have potential clinical applications.

The reversion of DNA methylation-induced miRNA silence via biomimetic nanoparticles-mediated gene delivery for efficient lung adenocarcinoma therapy

Background

Lung cancer is one of the fatal cancers worldwide, and over 60% of patients are lung adenocarcinoma (LUAD). Our clinical data demonstrated that DNA methylation of the promoter region of miR-126-3p was upregulated, which led to the decreased expression of miR-126-3p in 67 cases of lung cancer tissues, implying that miR-126-3p acted as a tumor suppressor. Transduction of miR-126-3p is a potential therapeutic strategy for treating LUAD, yet the physiological environment and properties of miRNA challenge current transduction approaches.

Methods

We evaluated the expression of miR-126-3p in 67 pairs of lung cancer tissues and the corresponding adjacent non-tumorous tissues by Reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The relationship between the overall survival of lung cancer patients and miR-126-3p was analyzed by the Cancer Genome Atlas cohort database (Oncolnc, http://www.oncolnc.org). We analyzed DNA methylation Methylation-specific PCR (MSP) analysis. To determine whether ADAM9 is the direct target of miR-126-3p, we performed the 3′-UTR luciferase reporter assay. The protein levels in the cells or tissues were evaluated with western blotting (WB) analysis. The biodistribution of nanoparticles were monitored by in vivo tracking system.

Results

We describe the development of novel stealth and matrix metalloproteinase 2 (MMP2)-activated biomimetic nanoparticles, which are constructed using MMP2-responsive peptides to bind the miR-126-3p (known as MAIN), and further camouflaged with red blood cell (RBC) membranes (hence named REMAIN). REMAIN was able to effectively transduce miRNA into lung cancer cells and release them via MMP2 responsiveness. Additionally, REMAIN possessed the advantages of the natural RBC membrane, including extended circulation time, lower toxicity, better biocompatibility, and immune escape. Moreover, in vitro and in vivo results demonstrated that REMAIN effectively induced apoptosis of lung cancer cells and inhibited LUAD development and progression by targeting ADAM9.

Conclusion

The novel style of stealth and MMP2-activated biomimetic nanoparticles show great potential in miRNA delivery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12943-022-01651-4.

miR-26a-5p Suppresses Wnt/β-Catenin Signaling Pathway by Inhibiting DNMT3A-Mediated SFRP1 Methylation and Inhibits Cancer Stem Cell-Like Properties of NSCLC

Background

Lung cancer is a malignant cancer which results in the most cancer incidence and mortality worldwide. There is increasing evidence that the pattern of DNA methylation affects tumorigenesis and progression. However, the molecules and mechanisms regulating DNA methylation remain unclear.

Methods

The expression of miR-26a-5p in NSCLC cell lines was detected by qPCR and verified in NSCLC tissues from TCGA using Limma R package. CCK-8 assay, plate clone formation assay, flow cytometry, and sphere formation assay were used to detect the cell proliferation, colony formation, cell cycle, and cancer stem cell- (CSC-) like property in NSCLC cell lines. The immunoblotting was used to detect the protein levels of DNMT3A, SFRP1, and Ki67. Global DNA methylation levels and DNA methylation levels of SFRP1 promoter were examined using ELISA and MSP-PCR assay, respectively. The distribution of β-catenin was examined using immunofluorescence (IF). Besides, xenograft mouse model was used to investigate the antitumor effects of miR-26a-5p in vivo. The pathology and protein levels were, respectively, detected by hematoxylin and eosin (H&E) and immunocytochemistry (IHC).

Results

The expression of miR-26a-5p was downregulated in the tumor tissues comparted to adjacent normal tissues as well as NSCLC cell lines compared to normal lung epithelial cell (BEAS2B). The overexpression of miR-26a-5p inhibited cell proliferation, colony formation, CSC-like property, and arrested cell cycle at G1 phase. DNMT3A was a target of miR-26a-5p and upregulated DNA methylation on SFRP1 promoter. Mechanistically, miR-26a-5p repressed cell proliferation, colony formation, CSC-like property, and arrested cell cycle at G1 phase by binding DNMT3A to reduce DNA methylation levels of SFRP1 then upregulated SFRP1 expression. Moreover, miR-26a-5p exerted antitumor effects in vivo.

Conclusion

Our results revealed that miR-26a-5p acted as a tumor suppressor through targeting DNMT3A to upregulate SFRP1 via reducing DNMT3A-dependent DNA methylation.

Targeting Epigenetic Modifiers of Tumor Plasticity and Cancer Stem Cell Behavior

Tumor heterogeneity poses one of the greatest challenges to a successful treatment of cancer. Tumor cell populations consist of different subpopulations that have distinct phenotypic and genotypic profiles. Such variability poses a challenge in successfully targeting all tumor subpopulations at the same time. Relapse after treatment has been previously explained using the cancer stem cell model and the clonal evolution model. Cancer stem cells are an important subpopulation of tumor cells that regulate tumor plasticity and determine therapeutic resistance. Tumor plasticity is controlled by genetic and epigenetic changes of crucial genes involved in cancer cell survival, growth and metastasis. Targeting epigenetic modulators associated with cancer stem cell survival can unlock a promising therapeutic approach in completely eradicating cancer. Here, we review various factors governing epigenetic dysregulation of cancer stem cells ranging from the role of epigenetic mediators such as histone and DNA methyltransferases, histone deacetylases, histone methyltransferases to various signaling pathways associated with cancer stem cell regulation. We also discuss current treatment regimens targeting these factors and other promising inhibitors in clinical trials.

CAMSAP1 Mutation Correlates With Improved Prognosis in Small Cell Lung Cancer Patients Treated With Platinum-Based Chemotherapy

Platinum-based chemotherapy is the first-line treatment for small cell lung cancer (SCLC). However, due to patients developing a resistance to the drug, most experience relapse and their cancer can become untreatable. A large number of recent studies have found that platinum drug sensitivity of various cancers is affected by specific gene mutations, and so with this study, we attempted to find an effective genetic biomarker in SCLC patients that indicates their sensitivity to platinum-based drugs. To do this, we first analyzed whole exome sequencing (WES) and clinical data from two cohorts to find gene mutations related to the prognosis and to the platinum drug sensitivity of SCLC patients. The cohorts used were the Zhujiang cohort (N = 138) and the cohort reported by George et al. (N = 101). We then carried out gene set variation analysis (GSVA) and gene set enrichment analysis (GSEA) to investigate possible molecular mechanisms through which these gene mutations affect patient prognosis and platinum drug sensitivity. We found that for SCLC patients, CAMSAP1 mutation can activate anti-tumor immunity, mediate tumor cell apoptosis, inhibit epithelial-mesenchymal transition (EMT), improve prognosis, and improve platinum drug sensitivity, suggesting that CAMSAP1 mutation may be a potential biomarker indicating platinum drug sensitivity and patient prognosis in SCLC.

[Differences in plasma miRNA levels in inferior petrosal sinus samples of patients with ACTH-dependent Cushing's syndrome]

BACKGROUND

For the last decades microRNAs (miR) have proven themselves as novel biomarkers for various types of diseases. Identification of specific circulating microRNA panel that differ patient with Cushing's disease (CD) and ectopic ACTH syndrome (EAS) could improve the diagnostic procedure.

AIM

to evaluate the differences in miR levels in plasma samples drained from inferior petrosal sinuses in patients with CD and EAS.

MATERIALS AND METHODS

single-center, case-control study: we enrolled 24 patients with ACTH-dependent Cushing's syndrome (CS) requiring bilateral inferior petrosal sinus sampling (BIPSS).  Among them 12 subjects were confirmed as CD (males=2, females=10; median age 46,5 [IR 33,8;53,5]) and 12 as EAS (males=4, females=8, median age 54 [IR 38,75;60,75]). BIPSS was performed through a percutaneous bilateral approach. Once catheters were properly placed, blood samples were withdrawn simultaneously from each petrosal sinus and a peripheral vein. Plasma samples from both sinuses were centrifuged and then stored at -80 C. MiRNA isolation from plasma was carried out by an miRneasy Plasma/Serum Kit (Qiagen, Germany) on the automatic QIAcube station according to the manufacturer protocol. To prevent degradation, we added 1 unit of RiboLock Rnase Inhibitor (Thermo Fisher Scientific, USA) per 1 μL of RNA solution. The concentration of total RNA in the aqueous solution was evaluated on a NanoVue Plus spectrophotometer (GE Healthcare, USA). The libraries were prepared by the QIAseq miRNA Library Kit following the manufacturer standard protocols. MiR expression was then analyzed by sequencing on Illumina NextSeq 500 (Illumina, USA).

RESULTS

108 miRNAs were differently expressed (p <0,05) in inferior petrosal sinus samples of patients with CD vs EAS. We divided these miRNAs into 3 groups based on the significance of the results. The first group consisted of samples with the highest levels of detected miR in both groups. Four miRNAs were included: miR-1203 was downregulated in CD vs EAS - 36.74 (p=0,013), and three other were upregulated in CD vs EAS: miR-383-3p 46.36 (p=0,01), miR-4290 6.84 (p=0,036), miR-6717-5p 4.49 (p=0,031). This miRs will be validated in larger cohorts using RT-qPCR.

CONCLUSION

Plasma miR levels differ in inferior petrosal samples taken from patients with CD vs EAS. These miRs need to be validated by different methods and in peripheral plasma samples in order to be used as potentially non-invasive biomarkers to differentiate ACTH-dependent CS.

DNMT3A epigenetically regulates key microRNAs involved in epithelial-to-mesenchymal transition in prostate cancer

Epithelial-to-Mesenchymal Transition (EMT) is involved in prostate cancer metastatic progression, and its plasticity suggests epigenetic implications. Deregulation of DNMTs and several miRNAs plays a relevant role in EMT, but their interplay has not been clarified yet. In this study we provide evidence that DNMT3A interaction with several miRNAs has a central role in an ex-vivo EMT prostate cancer model obtained via exposure of PC3 cells to conditioned media from cancer-associated fibroblasts (CM-CAFs). The analysis of the alterations of the miRNA profile shows that miR-200 family (miR-200a/200b/429, miR-200c/141), miR-205, and miR-203, known to modulate key EMT factors, are downregulated and hyper-methylated at their promoters. DNMT3A (mainly isoform a) is recruited onto these miRNA promoters, coupled with the increase of H3K27me3/H3K9me3 and/or the decrease of H3K4me3/H3K36me3. Most interestingly, our results reveal the differential expression of two DNMT3A isoforms (a and b) during ex-vivo EMT and a regulatory feedback loop between miR-429 and DNMT3A that can promote and sustain the transition toward a more mesenchymal phenotype. We demonstrate the ability of miR-429 to target DNMT3A 3'UTR and modulate the expression of EMT factors, in particular ZEB1. Survey of the PRAD-TCGA data set shows that patients expressing an EMT-like signature are indeed characterized by down-regulation of the same miRNAs with a diffused hyper-methylation at miR-200c/141 and miR-200a/200b/429 promoters. Finally, we show that miR-1260a also targets DNMT3A, although it does not seem involved in EMT in prostate cancer.

Circ_0084615 is an oncogenic circular RNA in colorectal cancer and promotes DNMT3A expression via repressing miR-599

BACKGROUND

Circular RNAs (circRNAs) are implicated in modulating cancer progression, exerting a pro- or anti-cancer effect. This work is aimed to probe the biological function of circ_0084615 in colorectal cancer (CRC) and its underlying mechanism.

METHODS

Circ_0084615 was selected from two circRNA microarray datasets (GSE138589 and GSE142837). Circ_0084615, microRNA (miR)-599 and DNA methyltransferases 3A (DNMT3A) mRNA expression in CRC tissues and cell lines were examined by qRT-PCR. The relationship between circ_0084615 expression level and clinical features were analyzed with chi-square test. Circ_0084615 knockdown model was constructed by siRNA in two CRC cell lines. The biological functions of circ_0084615 in CRC cells were evaluated by CCK-8 and Transwell experiments. The effect of circ_0084615 on CRC cell metastasis in vivo was examined with lung metastasis model of nude mice. Dual luciferase reporter gene assay was used to determine whether circ_0084615 and miR-599, and miR-599 and DNMT3A interacted with each other. Western blot was employed to examine the regulatory effects of circ_0084615 and miR-599 on DNMT3A protein expression in CRC cells.

RESULTS

Circ_0084615 was up-regulated in CRC and was correlated with poor overall survival rate and advanced clinical stage of CRC patients. Functional assays validated that depletion of circ_0084615 impeded CRC cell proliferation, migration and invasion. Circ_0084615 acted as a molecular sponge for miR-599 to repress its expression. DNMT3A was a downstream target of miR-599. Functional compensation experiments showed that miR-599 inhibitors partially counteracted the the biological effects of silencing circ_0084615 on CRC cells.

CONCLUSIONS

Circ_0084615 is a tumor-promoting circRNA in CRC that functions as a competing endogenous RNA to regulate DNMT3A expression via sponging miR-599. Our research provides a potential therapeutic target for CRC patients.

MicroRNA: A signature for cancer progression

MicroRNAs (miRNAs) are a group of small non-coding RNAs that post-transcriptionally control expression of genes by targeting mRNAs. miRNA alterations partake in the establishment and progression of different types of human cancer. Consequently, expression profiling of miRNA in human cancers has correlations with cancer detection, staging, progression, and response to therapies. Particularly, amplification, deletion, abnormal pattern of epigenetic factors and the transcriptional factors that mediate regulation of primary miRNA frequently change the landscape of miRNA expression in cancer. Indeed, changes in the quantity and quality of miRNAs are associated with the initiation of cancer, its progression and metastasis. Additionally, miRNA profiling has been used to categorize genes that can affect oncogenic pathways in cancer. Here, we discuss several circulating miRNA signatures, their expression profiles in different types of cancer and their impacts on cellular processes.

MiR-9-1 Suppresses Cell Proliferation and Promotes Apoptosis by Targeting UHRF1 in Lung Cancer

Lung cancer is listed as the most common reason for cancer-related death all over the world despite diagnostic improvements and the development of chemotherapy and targeted therapies. MicroRNAs control both physiological and pathological processes including development and cancer. A microRNA-9 to 1 (miR-9 to 1) overexpression model in lung cancer cell lines was established and miR-9 to 1 was found to significantly suppress the proliferation rate in lung cancer cell lines, colony formation in vitro, and tumorigenicity in nude mice of A549 cells. Ubiquitin-like containing PHD and RING finger domains 1 (UHRF1) was then identified to direct target of miR-9 to 1. The inhibition of UHRF1 by miR-9 to 1 causes G1 arrest and p15, p16, and p21 were re-expressed in miR-9 to 1 group in mRNA level and protein level. Silence of UHRF1 expression in A549 cells resulted in the similar re-expression of p15, p16, p21 which is similar with miR-9 to 1 infection. Therefore, we concluded that UHRF1 is a new target for miR-9 to 1 to suppress cell proliferation by re-expression of tumor suppressors p15, p16, and p21 mediated by UHRF1.

Head and Neck Squamous Cell Carcinoma: Epigenetic Landscape

Head and neck squamous carcinoma (HNSCC) constitutes the sixth most prevalent cancer worldwide. The molecular pathogenesis of HNSCC includes disorders in cell cycle, intercellular signaling, proliferation, squamous cell differentiation and apoptosis. In addition to the genetic mutations, changes in HNSCC are also characterized by the accumulation of epigenetic alterations such as DNA methylation, histone modifications, non-coding RNA activity and RNA methylation. In fact, some of them may promote cancer formation and progression by controlling the gene expression machinery, hence, they could be used as biomarkers in the clinical surveillance of HNSCC or as targets for therapeutic strategies. In this review, we focus on the current knowledge regarding epigenetic modifications observed in HNSCC and its predictive value for cancer development.

Screening of Methylation Gene Sites as Prognostic Signature in Lung Adenocarcinoma

PURPOSE

Most lung adenocarcinoma (LUAD) patients are diagnosed at the advanced stage and have poor prognosis. DNA methylation plays an important role in the prognosis prediction of cancers. The objective of this study was to identify new DNA methylation sites as biomarkers for LUAD prognosis.

MATERIALS AND METHODS

We downloaded DNA methylation data from The Cancer Genome Atlas data portal. Cox proportional hazard regression model and random survival forest algorithm were applied to identify the DNA-methylation sites. Methylation of sites were validated in the Gene Expression Omnibus cohorts. Function annotation were done to explore the biological function of DNA methylated sites signature.

RESULTS

Six DNA methylation sites were identified as prognosis signature. The signature yielded acceptable discrimination between the high-risk group and low-risk group. The discrimination effect of this DNA methylation signature for the OS was obvious, with a median OS of 21.89 months vs. 17.74 months for high-risk vs. low-risk groups. This prognostic prediction model was validated by the test group and GEO dataset. The predictive survival value was higher for the prognostic prediction model than that for the tumor node metastasis stage. Adjuvant hemotherapy could not affect the prediction of the signature. Functional analysis indicated that these signature genes were involved in protein binding and cytoplasm.

CONCLUSION

We identified the prognostic signature for LUAD by combining six DNA methylation sites. This could service as potential robust and specificity signature in the prognosis prediction of LUAD.

Prognostic roles of metabolic reprogramming-associated genes in patients with hepatocellular carcinoma

Metabolic reprogramming for adaptation to the tumor microenvironment is recognized as a hallmark of cancer. Although many altered metabolic genes have been reported to be associated with tumor pathological processes, systematic analysis of metabolic genes implicated in hepatocellular carcinoma prognosis remains rare. The aim of this study was to identify key metabolic genes related to hepatocellular carcinoma, and to explore their clinical significance. We downloaded mRNA expression profiles and clinical hepatocellular carcinoma data from The Cancer Genome Atlas database to explore the prognostic roles of metabolic genes. Five prognosis-associated metabolic genes, including POLA1, UCK2, ACYP1, ENTPD2, and TXNRD1, were screened via univariate Cox regression analysis and a LASSO Cox regression model, which divided patients into high- and low-risk groups. Furthermore, gene set enrichment analysis revealed that significantly-enriched gene ontology terms and pathways involving high-risk patients were focused on regulation of nucleic and fatty acid metabolism. Taken together, our study identified five metabolic genes related to survival, which can be used to predict the prognosis of patients with hepatocellular carcinoma. These genes may play essential roles in metabolic microenvironment regulation, and represent potentially important candidate targets in metabolic therapy.

Construction of a 13-microRNA-based signature and prognostic nomogram for predicting overall survival in patients with hepatocellular carcinoma

AIM

Hepatocellular carcinoma (HCC) is a common malignancy associated with a poor prognosis due to difficulties in reliably estimating overall survival (OS). MicroRNAs (miRNAs) play critical roles in HCC initiation, progression, and metastasis and are highly correlated with patient prognosis. Thus, miRNA-based risk signatures and nomograms are urgently required for predicting OS in patients with HCC.

METHODS

We constructed a 13-miRNA-based signature and prognostic nomogram using 408 HCC samples and 58 normal tissues with miRNA sequencing data and clinical data from 323 patients downloaded from The Cancer Genome Atlas. A total of 195 patients were assigned as the internal validation cohort for verification and testing. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis was applied to investigate pathway enrichment for the signature.

RESULTS

We identified and validated a 13-miRNA risk signature highly associating with the OS of HCC patients. The signature showed good performances by calculating C-index, area under the curve, and calibration curves. After verification and testing using an internal validation cohort, the results yielded a miRNA-based signature and a prognostic nomogram with reliable predictive accuracy. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis indicated that various genes and multiple pathways were closely related to the mechanisms of HCC proliferation and metastasis.

CONCLUSION

We successfully identified a 13-miRNA-based signature and prognostic nomogram that are capable of predicting OS in patients with HCC.

Tanshinone Inhibits NSCLC by Downregulating AURKA Through Let-7a-5p

Lung cancer is the most deadly malignancy in the last decade, accounting for about 1.6 million deaths every year globally. Tanshinone is the constituent of Salvia miltiorrhiza; it has been found that they influence tumorigenesis. However, the role of tanshinones on lung cancer is still not clear. Let-7a-5p, a short non-coding RNA, is regarded as a suppressor gene in tumorigenesis. Herein, we verified that let-7a-5p is significantly downregulated in non-small-cell lung cancer (NSCLC) tissues and cell lines. Tanshinone suppressed the expression of aurora kinase A (AURKA), inhibited cell proliferation, and arrested cell cycle progression. Our results showed that tanshinones suppressed NSCLC by upregulating the expressions of let-7a-5p via directly targeting AURKA. Besides, the data reveal that the knockdown of AURKA can also inhibit cell proliferation, arrest cell cycle, and promote cell apoptosis. Furthermore, this study demonstrates that AURKA was negatively correlated with let-7a-5p in NSCLC patient tissues. Taken together, our findings suggest that tanshinone inhibits NSCLC by downregulating AURKA through let-7a-5p. Tanshinones and let-7a-5p have the potential to be candidates for drug development of NSCLC. In conclusion, this study revealed that tanshinones with miRNA linking lead to partial mechanism in NSCLC.