LncRNA PVT1 regulates growth, migration, and invasion of bladder cancer by miR-31/ CDK1

Dual role of microRNA-31 in human cancers; focusing on cancer pathogenesis and signaling pathways

Widespread changes in the expression of microRNAs in cancer result in abnormal gene expression for the miRNAs that control those genes, which in turn causes changes to entire molecular networks and pathways. The frequently altered miR-31, which is found in a wide range of cancers, is one cancer-related miRNA that is particularly intriguing. MiR-31 has a very complicated set of biological functions, and depending on the type of tumor, it may act both as a tumor suppressor and an oncogene. The endogenous expression levels of miR-31 appear to be a key determinant of the phenotype brought on by aberrant expression. Varied expression levels of miR-31 could affect cell growth, metastasis, drug resistance, and other process by several mechanisms like targeting BRCA1-associated protein-1 (BAP1), large tumor suppressor kinase 1 (LATS1) and protein phosphatase 2 (PP2A). This review highlights the current understanding of the genes that miR-31 targets while summarizing the complex expression patterns of miR-31 in human cancers and the diverse phenotypes brought on by altered miR-31 expression.

A new method for network bioinformatics identifies novel drug targets for mucinous ovarian carcinoma

Mucinous ovarian carcinoma (MOC) is a subtype of ovarian cancer that is distinct from all other ovarian cancer subtypes and currently has no targeted therapies. To identify novel therapeutic targets, we developed and applied a new method of differential network analysis comparing MOC to benign mucinous tumours (in the absence of a known normal tissue of origin). This method mapped the protein-protein network in MOC and then utilised structural bioinformatics to prioritise the proteins identified as upregulated in the MOC network for their likelihood of being successfully drugged. Using this protein-protein interaction modelling, we identified the strongest 5 candidates, CDK1, CDC20, PRC1, CCNA2 and TRIP13, as structurally tractable to therapeutic targeting by small molecules. siRNA knockdown of these candidates performed in MOC and control normal fibroblast cell lines identified CDK1, CCNA2, PRC1 and CDC20, as potential drug targets in MOC. Three targets (TRIP13, CDC20, CDK1) were validated using known small molecule inhibitors. Our findings demonstrate the utility of our pipeline for identifying new targets and highlight potential new therapeutic options for MOC patients.

Exploration of PVT1 as a biomarker in prostate cancer

Prostate cancer is a malignant tumor originating from the prostate gland, significantly affecting patients' quality of life and survival rates. Public data was utilized to identify differentially expressed genes (DEGs). Weighted gene co-expression network analysis was constructed to classify gene modules. Functional enrichment analysis was performed through Kyoto Encyclopedia of Genes and Genomes and gene ontology annotations, with results visualized using the Metascape database. Additionally, gene set enrichment analysis evaluated gene expression profiles and related pathways, constructed a protein-protein interaction network to predict core genes, analyzed survival data, plotted heatmaps and radar charts, and predicted microRNAs for core genes through miRTarBase. Two prostate cancer datasets (GSE46602 and GSE55909) were analyzed, identifying 710 DEGs. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that DEGs were primarily involved in organic acid metabolism and the P53 signaling pathway. Gene set enrichment analysis and Metascape analyses further confirmed the significance of these pathways. After constructing the weighted gene co-expression network analysis network, 3 core genes (DDX21, NOP56, plasmacytoma variant translocation 1 [PVT1]) were identified. Survival analysis indicated that core genes are closely related to patient prognosis. Through comparative toxicogenomics database and miRNA prediction analysis, PVT1 was considered to play a crucial role in the development of prostate cancer. The PVT1 gene is highly expressed in prostate cancer and has the potential to become a diagnostic biomarker and therapeutic target for prostate cancer.

Current understanding of functional peptides encoded by lncRNA in cancer

Dysregulated gene expression and imbalance of transcriptional regulation are typical features of cancer. RNA always plays a key role in these processes. Human transcripts contain many RNAs without long open reading frames (ORF, > 100 aa) and that are more than 200 bp in length. They are usually regarded as long non-coding RNA (lncRNA) which play an important role in cancer regulation, including chromatin remodeling, transcriptional regulation, translational regulation and as miRNA sponges. With the advancement of ribosome profiling and sequencing technologies, increasing research evidence revealed that some ORFs in lncRNA can also encode peptides and participate in the regulation of multiple organ tumors, which undoubtedly opens a new chapter in the field of lncRNA and oncology research. In this review, we discuss the biological function of lncRNA in tumors, the current methods to evaluate their coding potential and the role of functional small peptides encoded by lncRNA in cancers. Investigating the small peptides encoded by lncRNA and understanding the regulatory mechanisms of these functional peptides may contribute to a deeper understanding of cancer and the development of new targeted anticancer therapies.

Identifying possible hub genes and biological mechanisms shared between bladder cancer and inflammatory bowel disease using machine learning and integrated bioinformatics

BACKGROUND

Recent studies have shown that inflammatory bowel disease (IBD) is associated with bladder cancer (BC) incidence. But there is still a lack of understanding regarding its pathogenesis. Thus, this study aimed to identify potential hub genes and their important pathways and pathological mechanisms of interactions between IBD and BC using bioinformatics methods.

METHODS

The data from Gene Expression Omnibus (GEO) and the cancer genome atlas (TCGA) were analyzed to screen common differentially expressed genes (DEGs) between IBD and BC. The "clusterProfiler" package was used to analyze GO term and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment in DEGs. After that, we conducted a weighted gene co-expression network analysis (WGCNA) on these DEGs to determine the vital modules and genes significantly related to BC. Protein-protein interaction (PPI) networks was used to identify hub genes. Further, the hub genes were used to develop a prognostic signature by Cox analysis. The validity of the ten hub DEGs was tested using three classification algorithms. Finally, we analyzed the microRNAs (miRNA)-mRNA, transcription factors (TFs)-mRNA regulatory network.

RESULTS

Positive regulation of organelle fission, chromosomal region, tubulin binding, and cell cycle signaling pathway were the major enriched pathways for the common DEGs. PPI networks identified three hub proteins (AURKB, CDK1, and CCNA2) with high connectivity. Three machine-learning classification algorithms based on ten hub genes performed well for IBD and BC (accuracy > 0.80). The robust predictive model based on the ten hub genes could accurately classify BC cases with various clinical outcomes. Based on the gene-TFs and gene-miRNAs network construction, 9 TFs and 6 miRNAs were identified as potential critical TFs and miRNAs. There are 13 drugs that interact with the hub gene based on gene-drug interaction analysis.

CONCLUSIONS

This study explored common gene signatures and the potential pathogenesis of IBD and BC. We revealed that an unbalanced immune response, cell cycle pathway, and neutrophil infiltration might be the common pathogenesis of IBD and BC. Molecular mechanisms for the treatment of IBD and CC still require further investigation.

A novel model based on disulfidptosis-related genes to predict prognosis and therapy of bladder urothelial carcinoma

PURPOSE

Disulfidptosis is a novel type of cell death induced by disulphide stress that depends on the accumulation of cystine disulphide, causing cytotoxicity and triggering cell death. However, the direct prognostic effect and regulatory mechanism of disulfidptosis-related genes in bladder urothelial carcinoma (BLCA) remain unclear.

METHODS

To explore the role of 10 disulfidptosis-related genes, the multiomic data of 10 genes were comprehensively analysed. Next, based on seven disulfidptosis-related differentially expressed genes, a novel disulfidptosis-related gene score was developed to help predict the prognosis of BLCA. Immunohistochemistry, EDU, Real-time PCR and western blot were used to verify the model.

RESULTS

Significant functional differences were found between the high- and low-risk score groups, and samples with a higher risk score were more malignant. Furthermore, the tumour exclusion and Tumour Immune Dysfunction and Exclusion scores of the high-risk score group were higher than those of the low-risk score group. The risk score was positively correlated with the expression of immune checkpoints. Drug sensitivity analyses revealed that the low-risk score group had a higher sensitivity to cisplatin, doxorubicin, docetaxel and gemcitabine than the high-risk score group. Moreover, the expression of the TM4SF1 was positively correlated with the malignancy degree of BLCA, and the proliferation ability of BLCA cells was reduced after knockdown TM4SF1.

CONCLUSION

The present study results suggest that disulfidptosis-related genes influence the prognosis of BLCA through their involvement in immune cell infiltration. Thus, these findings indicate the role of disulfidptosis in BLCA and its potential regulatory mechanisms.

Molecular landscape of LncRNAs in bladder cancer: From drug resistance to novel LncRNA-based therapeutic strategies

Bladder cancer (BC) is a common and serious type of cancer that ranks among the top ten most prevalent malignancies worldwide. Due to the high occurrence rate of BC, the aggressive nature of cancer cells, and their resistance to medication, managing this disease has become a growing challenge in clinical care. Long noncoding RNAs (lncRNAs) are a group of RNA transcripts that do not code for proteins and are more than 200 nucleotides in length. They play a significant role in controlling cellular pathways and molecular interactions during the onset, development and progression of different types of cancers. Recent advancements in high-throughput gene sequencing technology have led to the identification of various differentially expressed lncRNAs in BC, which indicate abnormal expression. In this review, we summarize that these lncRNAs have been found to impact several functions related to the development of BC, including proliferation, cell growth, migration, metastasis, apoptosis, epithelial-mesenchymal transition, and chemo- and radio-resistance. Additionally, lncRNAs may improve prognosis prediction for BC patients, indicating a future use for them as prognostic and diagnostic biomarkers for BC patients. This review highlights that genetic tools and anti-tumor agents, such as CRISPR/Cas systems, siRNA, shRNA, antisense oligonucleotides, and vectors, have been created for use in preclinical cancer models. This has led to a growing interest in using lncRNAs based on positive research findings.

LncRNA PVT1 promotes bladder cancer progression by forming a positive feedback loop with STAT5B

BACKGROUND

Plasmacytoma Variant Translocation 1 (LncRNA PVT1) and signal transducer and activator of transcription 5B (STAT5B) play important roles in various cancers, but their interaction in bladder cancer (BC) remains unclear.

PURPOSE

We aimed to explore the interaction between lncRNA PVT1 and STAT5B in BC tumorigenesis and find potential drugs for BC.

METHODS

The association of the expression of lncRNA PVT1 and STAT5B to the prognosis of BC patients was evaluated via bioinformatic analysis. Loss- and gain-of-function assays were performed to determine the biological functions of lncRNA PVT1 and STAT5B. Quantitative real time polymerase chain reaction, Western blot, immunohistochemistry, and immunofluorescence were used to detect lncRNA PVT1 and STAT5B expression. Fluorescence in situ hybridization, RNA pull-down and RNA immunoprecipitation assays were conducted to determine the regulatory effect of lncRNA PVT1 on STAT5B. The transcriptional effect of STAT5B on lncRNA PVT1 gene was determined using luciferase reporter assay, chromatin immunoprecipitation and DNA-affinity precipitation assays. Connectivity Map analysis was used to screen anticancer drugs.

RESULTS

LncRNA PVT1 and STAT5B enhance the expression of each other and promote the malignant phenotypes in BC, including cell viability and invasion. lncRNA PVT1 stabilizes STAT5B by decreasing ubiquitination, enhances STAT5B phosphorylation, and promotes the translocation to the nucleus of STAT5B to trigger further carcinogenesis activities. In the nucleus, STAT5B activates the transcription of lncRNA PVT1 by binding directly to its promoter region, leading to a positive feedback. Tanespimycin effectively abated the oncogenic effect.

CONCLUSIONS

We first identified the lncRNA PVT1/STAT5B positive feedback loop for bladder carcinogenesis, and found a potentially effective drug for BC.

Circular RNA hsa_circ_0005218 promotes the early recurrence of hepatocellular carcinoma by targeting the miR-31-5p/CDK1 pathway

Increasing evidence has manifested that circular RNAs (circRNAs) exhibited critical function in regulating various signaling pathways related to hepatocellular carcinoma (HCC) recurrence. However, the role and mechanism of the circRNAs in the HCC early recurrence remain elusive. In this study, high-throughput RNA-sequencing (RNA-seq) analysis was conducted to identify the expression profile of circRNAs in HCC tissues and circ_0005218 was identified as one circRNA that significantly up-regulated in early recurrent HCC tissues. And patients with high expression of circ_0005218 showed worsen overall survival (OS) and disease-free survival (DFS). Moreover, the promotion effects of circ_0005218 on HCC cells in term of proliferation, invasion and metastasis were confirmed both in vitro and vivo by gain- and loss-of function assays. In addition, dual-luciferase reporter assays showed that circ_0005218 could competitively bind to micro-RNA (miR)-31-5p. Furthermore, we showed that suppression of CDK1 by miR-31-5p could be partially rescued by up-regulating circ_0005218. Taken together, the present study indicates that circ_0005218 absorbed miR-31-5p as a sponge to weaken its suppression on CDK1 expression, and thus boost HCC cell invasion and migration, which would act as a potential biomarker to predict the HCC early recurrence and as a new therapeutic target for treatment of HCC.

17β-estradiol suppresses H2O2-induced senescence in human umbilical vein endothelial cells by inducing autophagy through the PVT1/miR-31/SIRT3 axis

OBJECTIVE

17β-estradiol (17β-E₂) has been implicated in activating autophagy by upregulating SIRT3 (Sirtuin 3) expression, thereby inhibiting the senescence of vascular endothelial cells. Herein, we further examined the molecular mechanisms that regulate SIRT3 expression in 17β-E₂-induced autophagy.

METHODS

Reverse-transcription-polymerase chain reaction was employed to measure the expression of plasmacytoma variant translocation 1 (PVT1), microRNAs (miRNAs), and SIRT3, and the dual-luciferase assay was used to determine their interaction. Electron microscopy observes autophagosomes, green fluorescent protein-microtubule-associated protein 1 light chain 3 (GFP-LC3) staining, and immunoblot analysis with antibodies against LC3，beclin-1, and P62 were conducted to measure autophagy. Cellular senescence was determined using immunoblot analysis with anti-phosphorylated retinoblastoma and senescence-associated β-galactosidase staining.

RESULTS

Women with higher estrogen levels (during the 10-13th day of the menstrual cycle or premenopausal) exhibit markedly higher serum levels of PVT1 than women with lower estrogen levels (during the menstrual period or postmenopausal). The dual-luciferase assay showed that PVT1 acts as a sponge for miR-31, and miR-31 binds to its target gene, SIRT3. The 17β-E₂ treatment increased the expression of PVT1 and SIRT3 and downregulated miR-31 expression in human umbilical vein endothelial cells (HUVECs). Consistently, PVT1 overexpression suppresses miR-31 expression, promotes 17β-E2-induced autophagy, and inhibits H₂O₂-induced senescence. miR-31 inhibitor increases SIRT3 expression and leads to activation of 17β-E₂-induced autophagy and suppression of H₂O₂-induced senescence.

CONCLUSION

Our findings demonstrated that 17β-E₂ upregulates PVT1 gene expression and PVT1 functions as a sponge to inhibit miR-31, resulting in the upregulation of SIRT3 expression and activation of autophagy and subsequent inhibition of H₂O₂-induced senescence in HUVECs.

Emerging RNA-Based Therapeutic and Diagnostic Options: Recent Advances and Future Challenges in Genitourinary Cancers

Renal cell carcinoma, bladder cancer, and prostate cancer are the most widespread genitourinary tumors. Their treatment and diagnosis have significantly evolved over recent years, due to an increasing understanding of oncogenic factors and the molecular mechanisms involved. Using sophisticated genome sequencing technologies, the non-coding RNAs, such as microRNAs, long non-coding RNAs, and circular RNAs, have all been implicated in the occurrence and progression of genitourinary cancers. Interestingly, DNA, protein, and RNA interactions with lncRNAs and other biological macromolecules drive some of these cancer phenotypes. Studies on the molecular mechanisms of lncRNAs have identified new functional markers that could be potentially useful as biomarkers for effective diagnosis and/or as targets for therapeutic intervention. This review focuses on the mechanisms underlying abnormal lncRNA expression in genitourinary tumors and discusses their role in diagnostics, prognosis, and treatment.

lncRNA-mediated ceRNA network in bladder cancer

Bladder cancer is a common disease associated with high rates of morbidity and mortality. Although immunotherapy approaches such as adoptive T-cell therapy and immune checkpoint blockade have been investigated for the treatment of bladder cancer, their off-target effects and ability to affect only single targets have led to clinical outcomes that are far from satisfactory. Therefore, it is important to identify novel targets that can effectively control tumor growth and metastasis. It is well known that long noncoding RNAs (lncRNAs) are powerful regulators of gene expression. Increasing evidence has shown that dysregulated lncRNAs in bladder cancer are involved in cancer cell proliferation, migration, invasion, apoptosis, and epithelial-mesenchymal transition (EMT). In this review, we focus on the roles and underlying mechanisms of lncRNA-mediated competing endogenous RNA (ceRNA) networks in the regulation of bladder cancer progression. In addition, we discuss the potential of targeting lncRNA-mediated ceRNA networks to overcome cancer treatment resistance and its association with clinicopathological features and outcomes in bladder cancer patients. We hope this review will stimulate research to develop more effective therapeutic approaches for bladder cancer treatment.

The RNA demethylase ALKBH5 promotes the progression and angiogenesis of lung cancer by regulating the stability of the LncRNA PVT1

Background

N6-methyladenosine (m6A) is the most common posttranscriptional modification of RNA and plays critical roles in human cancer progression. However, the biological function of m6A methylation requires further studied in cancer, especially in tumor angiogenesis.

Methods

A public database was used to analyze the expression and overall survival of ALKBH5 and PVT1 in lung cancer patients. CCK-8 and colony formation assays were performed to detect cell proliferation, a transwell assay was used to assess cell migration, and a tube formation assay was performed to assess angiogenic potential in vitro. A zebrafish lung cancer xenograft model was used to verify the function of ALKBH5 and PVT1 in vivo. Western blot assays were used to measure the relative protein expression in lung cancer cells. SRAMP predictor analysis and RNA stability experiments were used to examine the potential m6A modification.

Results

Bioinformatics analysis showed that the expression levels of m6A-related genes were changed significantly in lung cancer tissues compared with normal lung tissues. We then identified that ALKBH5 was upregulated in lung cancer tissues and associated with poor prognosis of lung cancer patients by analyzing a public database. Knockdown of ALKBH5 inhibited the proliferation and migration of cultured lung cancer cell lines. Zebrafish lung cancer xenografts showed that ALKBH5 silencing also suppressed the growth and metastasis of lung cancer cells. Moreover, knockdown of ALKBH5 inhibited the angiogenesis of lung cancer in vitro and in vivo. Mechanistic studies showed that knockdown of ALKBH5 decreased the expression and stability of PVT1 in lung cancer cells. We next observed that PVT1 promoted the progression of lung cancer cells in vitro and in vivo and regulated the expression of VEGFA and angiogenesis in lung cancer. Finally, rescue experiments revealed that ALKBH5 regulated the proliferation, migration and angiogenesis of lung cancer cells, partially through PVT1.

Conclusion

Our results demonstrate that ALKBH5 promotes the progression and angiogenesis of lung cancer by regulating the expression and stability of PVT1, which provides a potential prognostic and therapeutic target for lung cancer patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02770-0.

A review on the role of cyclin dependent kinases in cancers

The Cyclin-dependent kinase (CDK) class of serine/threonine kinases has crucial roles in the regulation of cell cycle transition and is mainly involved in the pathogenesis of cancers. The expression of CDKs is controlled by a complex regulatory network comprised of genetic and epigenetic mechanisms, which are dysregulated during the progression of cancer. The abnormal activation of CDKs results in uncontrolled cancer cell proliferation and the induction of cancer stem cell characteristics. The levels of CDKs can be utilized to predict the prognosis and treatment response of cancer patients, and further understanding of the function and underlying mechanisms of CDKs in human tumors would pave the way for future cancer therapies that effectively target CDKs. Defects in the regulation of cell cycle and mutations in the genes coding cell-cycle regulatory proteins lead to unrestrained proliferation of cells leading to formation of tumors. A number of treatment modalities have been designed to combat dysregulation of cell cycle through affecting expression or activity of CDKs. However, effective application of these methods in the clinical settings requires recognition of the role of CDKs in the progression of each type of cancer, their partners, their interactions with signaling pathways and the effects of suppression of these kinases on malignant features. Thus, we designed this literature search to summarize these findings at cellular level, as well as in vivo and clinical levels.

lncRNA PVT1: a novel oncogene in multiple cancers

Long noncoding RNAs are involved in epigenetic gene modification, including binding to the chromatin rearrangement complex in pre-transcriptional regulation and to gene promoters in gene expression regulation, as well as acting as microRNA sponges to control messenger RNA levels in post-transcriptional regulation. An increasing number of studies have found that long noncoding RNA plasmacytoma variant translocation 1 (PVT1) plays an important role in cancer development. In this review of a large number of studies on PVT1, we found that PVT1 is closely related to tumor onset, proliferation, invasion, epithelial–mesenchymal transformation, and apoptosis, as well as poor prognosis and radiotherapy and chemotherapy resistance in some cancers. This review comprehensively describes PVT1 expression in various cancers and presents novel approaches to the diagnosis and treatment of cancer.

The Effect of lncRNA-PVT1 on Liver Cancer Rats by Regulating the Expression of MMP9

As a malignant tumor, liver cancer has a high lethality rate. The research on the pathogenesis of liver cancer is the key to the treatment of liver cancer. The latest research claims that lncRNA-PVT1 as a tumor gene participates in the generation and development of tumors by regulating matrix metalloproteinase MMP9. The purpose of this article is to explore the specific effect and mechanism of lncRNA-PVT1 on liver cancer rats by regulating the expression of MMP9. In this article, 50 rats are used as experimental subjects, the rats are divided into control group and observation group, and the liver cancer cell line HepG2 is cultured. The transplanted tumor liver cancer model was constructed by transfection of hair, the expression of lncRNA-PVT1 in the observation group was reduced by knockdown method, the expression levels and changes of lncRNA-PVT1 and MMP9 in the two groups were detected by PCR fluorescence method, and the difference between lncRNA-PVT1 and MMP9 was analyzed. The MTT method was used to detect the proliferation, migration, and invasion capabilities of the two groups of liver cancer cells (LCC) and to explore the effect of lncRNA-PVT1 on rat LCC by regulating the expression of MMP9. The results of the study showed that after knocking down the expression of lncRNA-PVT1 in the observation group, the expression of MMP9 also decreased. At the same time, the migration rate of LCC HepG2 decreased by 27.4%, the level of invasion ability decreased by 21.6%, and the proliferation rate of LCC decreased by 17.8%. Therefore, it can be seen that lncRNA-PVT1 plays a positive regulatory role on the expression of MMP9, and the expression of MMP9 promotes the proliferation, migration, and invasion of rat LCC.

Long non-coding RNA PVT1: A promising chemotherapy and radiotherapy sensitizer

The long non-coding RNA (lncRNA) PVT1 was first found to activate variant translocations in the plasmacytoma of mice. Human lncPVT1 is located on chromosome 8q24.21, at the same locus as the well-known MYC oncogene. LncPVT1 has been found to promote the progression of various malignancies. Chemoresistance and radioresistance seriously affect tumor treatment efficacy and are associated with the dysregulation of physiological processes in cancer cells, including apoptosis, autophagy, stemness (for cancer stem cells, CSC), hypoxia, epithelial–mesenchymal transition (EMT), and DNA damage repair. Previous studies have also implicated lncPVT1 in the regulation of these physiological mechanisms. In recent years, lncPVT1 was found to modulate chemoresistance and radioresistance in some cancers. In this review, we discuss the mechanisms of lncPVT1-mediated regulation of cellular chemoresistance and radioresistance. Due to its high expression in malignant tumors and sensitization effect in chemotherapy and radiotherapy, lncPVT1 is expected to become an effective antitumor target and chemotherapy and radiotherapy sensitizer, which requires further study.

KRT6A expedites bladder cancer progression, regulated by miR-31-5p

Bladder cancer is one of the most severe life-threatening illnesses worldwide. To contribute to a solution to this public health issue, here, we sought to identify a novel biomarker for the early diagnosis of bladder tumors. We conducted RNA sequence analysis utilizing samples from tumorous tissue and adjacent healthy tissue in bladder cancer patients and found that KRT6A was upregulated in bladder tumor tissues, suggesting that it might be a candidate for involvement in bladder tumorigenesis. Accordingly, we performed a series of experiments to further verify the role of KRT6A in bladder tumor progression. Our results revealed that KRT6A promoted bladder tumor cell viability, proliferation, and adhesion, while diminishing bladder tumor cell apoptosis. We also focused on the role of epigenetics in bladder tumors and verified that KRT6A was a miR-31-5p target gene, and its positive effect on bladder tumor progression was relieved by miR-31-5p. Overall, this study sheds new light regarding a novel oncogenic regulatory axis, KRT6A/miR-31-5p, which is related to bladder tumor growth.

LncRNA PVT1 contributes to invasion and doxorubicin resistance of bladder cancer cells through promoting MDM2 expression and AURKB-mediated p53 ubiquitination

In most bladder cancer (BC) patients, cancer cells will eventually develop chemical resistance causing increased mortality. This study aimed to explore the mechanism of lncRNA plasmacytoma variant translocation 1 (PVT1) in regulating doxorubicin (ADM) resistance of BC cells. We observed that PVT1 expression was upregulated in ADM-resistant BC cells compared with ADM-sensitive BC cells. Downregulation of PVT1 suppressed ADM-resistant BC cell proliferation and invasion, promoted apoptosis, and increased sensitivity to ADM, while PVT1 overexpression promoted ADM-sensitive BC cell growth and their resistance to ADM. Further study uncovered that PVT1 could interact with and promote mouse double minute 2 (MDM2) expression, and upregulated MDM2-mediated Aurora kinase B (AURKB). Furthermore, Nutlin-3, an inhibitor of MDM2, could counteract the promotive effects of PVT1 overexpression on ADM resistance of ADM-sensitive BC cell, the expression of multidrug-resistance-related proteins, and the inhibition of p53-mediated tumor suppressor genes. And, overexpression of MDM2 or AURKB reversed the promotive effects of PVT1 silence on the ADM sensitivity of ADM-resistant BC cell, and the inhibitory effect on expression multidrug resistance proteins. Mechanically, AURKB increased MDM2-mediated p53 ubiquitination. Taken together, PVT1 promoted BC cell proliferation and drug resistance via elevating MDM2 expression and AURKB-mediated p53 ubiquitination.

Clinical implications and molecular mechanisms of Cyclin-dependent kinases 4 for patients with hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) was frequently considered as a kind of malignant tumor with a poor prognosis. Cyclin-dependent kinases (CDK) 4 was considered to be cell-cycle-related CDK gene. In this study, we explored the clinical significance of CDK4 in HCC patients.

Methods

Data of HCC patients were obtained from The Cancer Genome Atlas database (TCGA) and the Gene Expression Omnibus (GEO) database. Kaplan–Meier analysis and Cox regression model were performed to calculate median survival time (MST) and the hazard ration (HR), respectively. The joint-effect analysis and prognostic risk score model were constructed to demonstrate significance of prognosis-related genes. The differential expression of prognostic genes was further validated using reverse transcription-quantitative PCR (RT-qPCR) of 58 pairs of HCC samples.

Results

CDK1 and CDK4 were considered prognostic genes in TCGA and GSE14520 cohort. The result of joint-effect model indicated patients in CDK1 and CDK4 low expression groups had a better prognosis in TCGA (adjusted HR = 0.491; adjusted P = 0.003) and GSE14520 cohort (adjusted HR = 0.431; adjusted P = 0.002). Regarding Kaplan–Meier analysis, high expression of CDK1 and CDK4 was related to poor prognosis in both the TCGA (P < 0.001 and = 0.001 for CDK1 and CDK4, respectively) and the GSE14520 cohort (P = 0.006 and = 0.033 for CDK1 and CDK4, respectively). However, only CDK4 (P = 0.042) was validated in RT-qPCR experiment, while CDK1 (P = 0.075) was not.

Conclusion

HCC patients with high CDK4 expression have poor prognosis, and CDK4 could be a potential candidate diagnostic biomarker for HCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02152-w.

Inferring Latent Disease-lncRNA Associations by Label-Propagation Algorithm and Random Projection on a Heterogeneous Network

Long noncoding RNA (lncRNA), a type of more than 200 nucleotides non-coding RNA, is related to various complex diseases. To precisely identify the potential lncRNA–disease association is important to understand the disease pathogenesis, to develop new drugs, and to design individualized diagnosis and treatment methods for different human diseases. Compared with the complexity and high cost of biological experiments, computational methods can quickly and effectively predict potential lncRNA–disease associations. Thus, it is a promising avenue to develop computational methods for lncRNA-disease prediction. However, owing to the low prediction accuracy ofstate of the art methods, it is vastly challenging to accurately and effectively identify lncRNA-disease at present. This article proposed an integrated method called LPARP, which is based on label-propagation algorithm and random projection to address the issue. Specifically, the label-propagation algorithm is initially used to obtain the estimated scores of lncRNA–disease associations, and then random projections are used to accurately predict disease-related lncRNAs.The empirical experiments showed that LAPRP achieved good prediction on three golddatasets, which is superior to existing state-of-the-art prediction methods. It can also be used to predict isolated diseases and new lncRNAs. Case studies of bladder cancer, esophageal squamous-cell carcinoma, and colorectal cancer further prove the reliability of the method. The proposed LPARP algorithm can predict the potential lncRNA–disease interactions stably and effectively with fewer data. LPARP can be used as an effective and reliable tool for biomedical research.

Association of lncRNA PVT1 Gene Polymorphisms with the Risk of Essential Hypertension in Chinese Population

Vascular dysfunction and hyperlipidemia are essential risk factors contributing to essential hypertension (EH). The plasmacytoma variant translocation 1 (PVT1) is involved in modulating angiogenesis in tumor tissues and plays an important role in fat differentiation in the progress of obesity. Therefore, we selected two tagSNPs of PVT1 (rs10956390 and rs80177647) to investigate whether they are contributing to the risk of hypertension in Chinese patients. In total, 524 adult patients with EH and 439 matched healthy controls were enrolled for two central of China. Results. PVT1 rs10956390 and rs80177647 polymorphisms were genotyped by using TaqMan assay. PVT1 rs10956390 TT genotype was associated with a decreased risk of EH (OR = 0.561, 95% CI = 0.372-0.846, P = 0.006), while rs80177647 TA genotype was associated with an increased risk (OR = 2.236, 95% CI = 1.515-3.301, P < 0.001). Rs10956390 T allele was associated with lower triglyceride levels in the plasma both from healthy and EH donors. What is more, there is an association between rs10956390 polymorphism and HDL-C level, as well as LDL-C. Conclusion. PVT1 rs10956390 and rs80177647 polymorphisms may contribute to the risk of EH in Chinese population by regulating blood lipid levels.

MicroRNA-337-3p impedes breast cancer progression by targeting cyclin-dependent kinase 1

MicroRNAs (miRNAs/miRs) function as key regulators in breast cancer (BC). The present study aimed to verify the function and molecular regulation of miR-337-3p in BC cells. Bioinformatics analysis was performed to screen key genes and miRNAs associated with BC. Reverse transcription-quantitative PCR and western blot analyses were performed to detect RNA and protein expression levels. Cell Counting Kit-8, BrdU and cell adhesion assays, and flow cytometric analysis were performed to assess the biological behaviors of BC cells. The dual-luciferase reporter, RNA pull-down assays, and Pearson's correlation analysis were performed to determine the association between miRNAs and mRNAs. Bioinformatics analysis revealed that miR-337-3p and cyclin-dependent kinase 1 (CDK1) acted as key regulators in BC. In addition, miR-337-3p was expressed at low levels in BC cells and tissues, which suppressed BC progression. CDK1 expression was upregulated in BC cells and tissues, which was associated with increased cell proliferation and adhesion, as well as decreased apoptosis in BC. Notably, miR-337-3p targeted CDK1 to inhibit BC cell progression. Taken together, the results of the present study suggest that miR-337-3p plays a tumor-suppressive role in BC by targeting CDK1.

Biological functions and clinical significance of long noncoding RNAs in bladder cancer

Bladder cancer (BCa) is one of the 10 most common cancers with high morbidity and mortality worldwide. Long noncoding RNAs (lncRNAs), a large class of noncoding RNA transcripts, consist of more than 200 nucleotides and play a significant role in the regulation of molecular interactions and cellular pathways during the occurrence and development of various cancers. In recent years, with the rapid advancement of high-throughput gene sequencing technology, several differentially expressed lncRNAs have been discovered in BCa, and their functions have been proven to have an impact on BCa development, such as cell growth and proliferation, metastasis, epithelial-mesenchymal transition (EMT), angiogenesis, and drug-resistance. Furthermore, evidence suggests that lncRNAs are significantly associated with BCa patients' clinicopathological characteristics, especially tumor grade, TNM stage, and clinical progression stage. In addition, lncRNAs have the potential to more accurately predict BCa patient prognosis, suggesting their potential as diagnostic and prognostic biomarkers for BCa patients in the future. In this review, we briefly summarize and discuss recent research progress on BCa-associated lncRNAs, while focusing on their biological functions and mechanisms, clinical significance, and targeted therapy in BCa oncogenesis and malignant progression.

Comprehensive analysis of lncRNAs as biomarkers for diagnosis, prognosis, and treatment response in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common histological type of renal carcinoma and has a high recurrence rate and poor outcome. Accurate patient risk stratification based on genetic markers can help to identify the high-risk patient for early and further treatments and would promote patient survival. Long non-coding RNAs (lncRNAs) have attracted widespread attention as biomarkers for early diagnosis, treatment, and prognosis because of their high specificity and sensitivity. Here, we performed a systematic search in NCBI PubMed and found 44 lncRNAs as oncogenes, 18 lncRNAs as tumor suppressors, 199 lncRNAs as diagnostic biomarkers, 62 lncRNAs as prognostic biomarkers, and 3 lncRNAs as predictive biomarkers for ccRCC. We also comprehensively discuss the biological functions and molecular regulatory mechanisms of lncRNAs in ccRCC. Overall, the present study is a systemic analysis to assess the expression and clinical value of lncRNAs in ccRCC, and lncRNAs hold promise to be diagnostic, prognostic, and predictive biomarkers.

Identification of 5 Hub Genes Related to the Early Diagnosis, Tumour Stage, and Poor Outcomes of Hepatitis B Virus-Related Hepatocellular Carcinoma by Bioinformatics Analysis

BACKGROUND

The majority of primary liver cancers in adults worldwide are hepatocellular carcinomas (HCCs, or hepatomas). Thus, a deep understanding of the underlying mechanisms for the pathogenesis and carcinogenesis of HCC at the molecular level could facilitate the development of novel early diagnostic and therapeutic treatments to improve the approaches and prognosis for HCC patients. Our study elucidates the underlying molecular mechanisms of HBV-HCC development and progression and identifies important genes related to the early diagnosis, tumour stage, and poor outcomes of HCC.

METHODS

GSE55092 and GSE121248 gene expression profiling data were downloaded from the Gene Expression Omnibus (GEO) database. There were 119 HCC samples and 128 nontumour tissue samples. GEO2R was used to screen for differentially expressed genes (DEGs). Volcano plots and Venn diagrams were drawn by using the ggplot2 package in R. A heat map was generated by using Heatmapper. By using the clusterProfiler R package, KEGG and GO enrichment analyses of DEGs were conducted. Through PPI network construction using the STRING database, key hub genes were identified by cytoHubba. Finally, KM survival curves and ROC curves were generated to validate hub gene expression.

RESULTS

By GO enrichment analysis, 694 DEGs were enriched in the following GO terms: organic acid catabolic process, carboxylic acid catabolic process, carboxylic acid biosynthetic process, collagen-containing extracellular matrix, blood microparticle, condensed chromosome kinetochore, arachidonic acid epoxygenase activity, arachidonic acid monooxygenase activity, and monooxygenase activity. In the KEGG pathway enrichment analysis, DEGs were enriched in arachidonic acid epoxygenase activity, arachidonic acid monooxygenase activity, and monooxygenase activity. By PPI network construction and analysis of hub genes, we selected the top 10 genes, including CDK1, CCNB2, CDC20, BUB1, BUB1B, CCNB1, NDC80, CENPF, MAD2L1, and NUF2. By using TCGA and THPA databases, we found five genes, CDK1, CDC20, CCNB1, CENPF, and MAD2L1, that were related to the early diagnosis, tumour stage, and poor outcomes of HBV-HCC.

CONCLUSIONS

Five abnormally expressed hub genes of HBV-HCC are informative for early diagnosis, tumour stage determination, and poor outcome prediction.

PVT1 and ZFAS1 lncRNAs expressions and their biomarker value in gastric cancer tissue sampling among Iranian population

BACKGROUND

lncRNAs are modulatory factors with critical function in the tumorigenesis pathways, introducing them as promising therapeutic and diagnostic biomarkers for different cancers. This study is thus aimed to evaluate the differences in PVT1 and ZFAS1 gene expression in tumorous tissues as compared with adjacent healthy non-tumorous biopsies of gastric cancer cases.

METHODS

One hundred two pairs of tumorous and adjacent non-tumorous biopsies of GC cases were sampled. RNA isolation and cDNA production were carried out. The qRT-PCR was performed to evaluate the expression of PVT1 and ZFAS1 genes. Moreover, the associations between PVT1 or ZFAS1 and clinicopathological characteristics as well as the biomarker roles of the lncRNAs were assessed.

RESULTS

The PVT1 and ZFAS1 expressions showed a significant increase and decrease in GC samples as compared with non-cancerous tissues, respectively. PVT1 expression was significantly associated with and lymph-node involvement (p = 0.0007). Moreover, ZFAS1 expression demonstrated a significant association with lymph-node involvement (p = 0.0005), and tumor size >5 cm (p = 0.003). The findings of the ROC curve revealed that PVT1 and ZFAS1 may act as a possible biomarker with AUC of 0.71 and 0.79, specificity of 78.43% and 79.41%, and sensitivity of 55.88% and 64.71%.

CONCLUSIONS

Regarding upregulation of PVT1 and downregulation of ZFAS1 in human GC samples, these genes may respectively act as oncogenic and tumor-suppressive factors in GC cases. Furthermore, PVT1 and ZFAS1 can be considered as possible biomarkers for the detection and treatment of GC cases.

Long non-coding RNAs as new players in bladder cancer: Lessons from pre-clinical and clinical studies

The clinical management of bladder cancer (BC) has become an increasing challenge due to high incidence rate of BC, malignant behavior of cancer cells and drug resistance. The non-coding RNAs are considered as key factors involved in BC progression. The long non-coding RNAs (lncRNAs) are RNA molecules and do not encode proteins. They have more than 200 nucleotides in length and affect gene expression at epigenetic, transcriptional and post-transcriptional phases. The lncRNAs demonstrate abnormal expression in BC cells and tissues. The present aims to identifying lncRNAs with tumor-suppressor and tumor-promoting roles, and evaluating their roles as regulatory of growth and migration. Apoptosis, glycolysis and EMT are tightly regulated by lncRNAs in BC. Response of BC cells to cisplatin, doxorubicin and gemcitabine chemotherapy is modulated by lncRNAs. LncRNAs regulate immune cell infiltration in tumor microenvironment and affect response of BC cells to immunotherapy. Besides, lncRNAs are able to regulate microRNAs, STAT3, Wnt, PTEN and PI3K/Akt pathways in affecting both proliferation and migration of BC cells. Noteworthy, anti-tumor compounds and genetic tools such as siRNA, shRNA and CRISPR/Cas systems can regulate lncRNA expression in BC. Finally, lncRNAs and exosomal lncRNAs can be considered as potential diagnostic and prognostic tools in BC.

Knockdown of PSMC2 contributes to suppression of cholangiocarcinoma development by regulating CDK1

Cholangiocarcinoma (CCA) has been well known as the second most common primary tumor of hepatobiliary system. PSMC2 (proteasome 26S subunit ATPase 2) is a key member of the 19S regulatory subunit of 26S proteasome, responsible for catalyzing the unfolding and translocation of substrates into the 20S proteasome, whose role in CCA is totally unknown. In this study, the results of immunohistochemistry analysis showed the upregulation of PSMC2 in CCA tissues compared with normal tissues, which was statistically analyzed to be associated with CCA tumor grade. Subsequently, the loss-of-function study suggested that knockdown of PSMC2 significantly suppressed cell proliferation, cell migration, promoted cell apoptosis and arrested cell cycle distribution in vitro. The decreased tumorigenicity of CCA cells with PSMC2 knockdown was confirmed in vivo by using mice xenograft model. In PSMC2 knockdown cells, pro-apoptotic protein Caspase3 was upregulated; anti-apoptotic proteins such as Bcl-2 and IGF-II were downregulated; among EMT markers, E-cadherin was upregulated while N-cadherin and Vimentin were downregulated, by which may PSMC2 regulates cell apoptosis and migration. Furthermore, through RNA-seq and verification by qPCR, western blotting and co-IP assays, CDK1 was identified as the potential downstream of PSMC2 mediated regulation of CCA. PSMC2 and CDK1 showed mutual regulation effects on expression level of each other. Knockdown of PSMC2 could aggregate the influence of CDK1 knockdown on cellular functions of CCA cells. In summary, our findings suggested that PSMC2 possesses oncogene-like functions in the development and progression of CCA through regulating CDK1, which may be used as an effective therapeutic target in CCA treatment.

Long Noncoding RNA KCNMB2-AS1 Promotes SMAD5 by Targeting miR-3194-3p to Induce Bladder Cancer Progression

Purpose

Bladder cancer is a common malignant tumor of the urinary system, with the fourth-highest incidence of male malignant tumors in Europe and the United States. So far, the mechanism of bladder cancer progression and metastasis has not been clarified. The aim of our study was to validate the way of long noncoding RNA (lncRNA) KCNMB2-AS1 on the metabolism and growth of bladder cancer cells by miR-3194-3p/SMAD5.

Patients and Methods

The Gene Expression was analyzed by qRT-PCR in bladder cancer tissues and cell lines, with the highly expressed KCNMB2-AS1 screened out. Cell proliferation was detected by Edu staining and clone formation assay, cell migration, and invasion by wound healing and transwell assays. Cell stemness was determined by assessing sphere-forming ability and stemness marker. Correlation between miRNA and lncRNA/gene was verified by dual‐luciferase assay and RIP, and the effect of KCNMB2-AS1 on bladder cancer growth by nude mice tumor formation experiment.

Results

Here, we revealed the increased level of KCNMB2-AS1 in bladder cancer for the first time. Knockdown of KCNMB2-AS1 in vitro prevented the ability of proliferation, metastasis, and stemness of cancer cells. In vivo, the silencing of KCNMB2-AS1 also prevented tumor growth in vivo. Next, we revealed that KCNMB2-AS1 could interact with miR-3194-3p and uncovered that SAMD5 was a downstream target of miR-3194-3p.

Conclusion

In conclusion, KCNMB2-AS1 mediated the bladder cancer cells progress by regulating the miR-3194-3p/SAMD5 signal pathway, which would provide a new target for bladder cancer research.

Exosomes-mediated transfer of long noncoding RNA LINC01133 represses bladder cancer progression via regulating the Wnt signaling pathway

Bladder cancer (BC), as one of the most common malignant cancers of the urinary system, has a high incidence and mortality rates. Recently, increasing studies have indicated that exosomes can mediate cellular communication in assorted cancers, including BC. Long noncoding RNAs (lncRNAs) have also been confirmed to take part in the regulation of many cancers. Long intergenic non-protein coding RNA 1133 (LINC01133) is an lncRNA and its roles in several cancers have been revealed. However, the functions of exosomes and LINC01133 in BC are still not elucidated. In our research, functional assays were conducted to evaluate the function of LINC01133, as well as the influence of exosomes and LINC01133 on BC cells. Western blot assay, immunofluorescence assay, electron microscope, and nanoparticle tracking analysis were applied for detecting the characteristics of exosomes. Bioinformatics tools and quantitative reverse-transcription polymerase chain reaction were performed to test the expression of LINC01133 in BC cells and exosomes of the immortalized human uroepithelial cell line (SV-HUC-1). Luciferase reporter assay was performed to measure the activity of the Wnt pathway. We discovered that LINC01133 expression was high in exosomes of SV-HUC-1 and low in that of BC cells. Additionally, exosomes restrained cell viability, proliferation, migration, and invasion. Similarly, LINC01133 exerted the same function on BC cells. In addition, the Wnt signaling pathway could be inactivated by LINC01133. Finally, in vivo experiments demonstrated that cell growth could be suppressed by overexpressed LINC01133. In short, exosomes-mediated transfer of lncRNA LINC01133 repressed BC progression via regulating the Wnt signaling pathway.

Retracted: Sevoflurane improves nerve regeneration and repair of neurological deficit in brain damage rats via microRNA-490-5p/CDK1 axis

BACKGROUND

Sevoflurane (Sevo) is neuroprotective in brain damage, thus our objective was to further investigate the impact of Sevo treatment on nerve regeneration and repair of neurological deficit in brain damage rats by regulating miR-490-5p and cyclin-dependent kinases 1 (CDK1).

METHODS

The rat middle cerebral artery occlusion model was established. miR-490-5p and CDK1 levels in brain tissues were tested. The behavioral changes, the number of glial fibrillary acidic protein (GFAP) positive cells, ionized calcium-binding adapter molecule-1 (Iba-1) and Nestin mRNA expression, the survival and apoptosis of neurons in peripheral tissues of infarct areas were detected by a series of assays. Furthermore, the target relationship between miR-490-5p and CDK1 was verified.

RESULTS

miR-490-5p was reduced and CDK1 was raised in brain tissues of brain damage rats. Sevo raised miR-490-5p and decreased CDK1 to improve neurological deficits, reduce apoptotic neurons, suppress expression levels of GFAP and Iba-1, and increase Nestin expression and the number of surviving neurons in peripheral tissue in infarct area, and alleviate the pathological changes of brain tissues of brain damage rats. CDK1 was negatively regulated by miR-490-5p.

CONCLUSION

Our study presents that Sevo treatment is involved in neurogenesis and repair of neurological deficit of brain damage rats via up-regulating miR-490-5p and inhibiting CDK1.

Emerging Biomarkers for Predicting Bladder Cancer Lymph Node Metastasis

Bladder cancer is one of the leading causes of cancer deaths worldwide. Early detection of lymph node metastasis of bladder cancer is essential to improve patients' prognosis and overall survival. Current diagnostic methods are limited, so there is an urgent need for new specific biomarkers. Non-coding RNA and m6A have recently been reported to be abnormally expressed in bladder cancer related to lymph node metastasis. In this review, we tried to summarize the latest knowledge about biomarkers, which predict lymph node metastasis in bladder cancer and their mechanisms. In particular, we paid attention to the impact of non-coding RNA on lymphatic metastasis of bladder cancer and its specific molecular mechanisms, as well as some prediction models based on imaging, pathology, and biomolecules, in an effort to find more accurate diagnostic methods for future clinical application.

LINC01315 promotes the aggressive phenotypes of papillary thyroid cancer cells by sponging miR-497-5p

Dysregulation of the long intergenic noncoding RNA 01315 (LINC01315) has recently been demonstrated in cancer. However, the role of LINC01315 in papillary thyroid cancer (PTC) has not been determined. We attempted to determine the function of LINC01315 in PTC. The levels of LINC01315 were higher in thyroid carcinoma tissues and cell lines compared with that in noncancerous tissues or normal cells, respectively. LINC01315 knockdown significantly inhibited the in vitro colony formation and invasion of PTC cells. Upregulation of LINC01315 produced opposite effects. Bioinformatic analysis and luciferase reporter assays indicated direct binding of miR-497-5p to LINC01315. Gain- and loss-of-function assays indicated that miR-497-5p acts as a suppressive miRNA in PTC. Furthermore, LINC01315 facilitated the growth and invasion of PTC cells by sponging miR-497-5p. Our results demonstrated the critical role of the LINC01315-miR-497-5p axis in the growth and invasion of PTC cells.

miR-378a-5p inhibits the proliferation of colorectal cancer cells by downregulating CDK1

BACKGROUND

MicroRNAs (miRNAs) play an important role in tumor occurrence. The role of miR-378a-5p and CDK1 in colorectal cancer (CRC) was investigated in this study.

METHODS

Investigation of TCGA database and the detection of miR-378a-5p expression in colorectal cancer pathological tissues and colorectal cancer cell lines were undertaken by using qRT-PCR. We performed cell function experiments (CCK-8 assay, EdU assay, colony formation assay, wound healing assay, transwell assay, cell apoptosis assessment, and cell cycle assessment) and nude mouse tumor formation experiments to evaluate the effects of miR-378a-5p on proliferation, metastasis, and invasion to explore the role of miR-378a-5p in vivo and in vitro. Next, through TCGA database, immunohistochemical staining of pathological tissues, and cell function experiments, the role of the target gene CDK1 of miR-378a-5p was verified by database prediction, and dual luciferase reporter gene experiments in colorectal cancer cells were performed. Finally, whether upregulation of CDK1 restores the inhibitory effect of overexpression of miR-378a-5p on the proliferation of CRC cells was studied by overexpression of CDK1.

RESULTS

Bioinformatic analysis showed significant downregulation of miR-378a-5p levels in colorectal cancer (CRC). Cell function experiments and tumor xenograft mouse models confirmed the low expression of miR-378a-5p within CRC tissues, which indicated the tumor suppressive role of miR-378a-5p in CRC. To better explore the regulation of miR-378a-5p in CRC, we predicted and validated cell cycle-dependent protein kinase 1 (CDK1) as the miR-378a-5p target gene and observed that miR-378a-5p suppressed CRC cell proliferation by targeting CDK1.

CONCLUSION

The results of this study help to elucidate the mechanism by which miR-378a-5p can be used as a tumor marker to inhibit the growth of colorectal cancer and CDK1, which is related to the prognosis of colorectal cancer patients. MiR-378a-5p inhibits CRC cell proliferation by suppressing CDK1 expression, which may become a possible therapeutic target for treatment of CRC.

Immunotherapy Targeting Myeloid-Derived Suppressor Cells (MDSCs) in Tumor Microenvironment

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells that accumulate in tumor-bearing hosts to reduce T cells activity and promote tumor immune escape in the tumor microenvironment (TME). The immune system in the TME can be stimulated to elicit an anti-tumor immune response through immunotherapy. The main theory of immunotherapy resides on the plasticity of the immune system and its capacity to be re-educated into a potent anti-tumor response. Thus, MDSCs within the TME became one of the major targets to improve the efficacy of tumor immunotherapy, and therapeutic strategies for tumor MDSCs were developed in the last few years. In the article, we analyzed the function of tumor MDSCs and the regulatory mechanisms of agents targeting MDSCs in tumor immunotherapy, and reviewed their therapeutic effects in MDSCs within the TME. Those data focused on discussing how to promote the differentiation and maturation of MDSCs, reduce the accumulation and expansion of MDSCs, and inhibit the function, migration and recruitment of MDSCs, further preventing the growth, invasion and metastasis of tumor. Those investigations may provide new directions for cancer therapy.

8q24.21 Locus: A Paradigm to Link Non-Coding RNAs, Genome Polymorphisms and Cancer

The majority of the human genome is comprised of non-protein-coding genes, but the relevance of non-coding RNAs in complex diseases has yet to be fully elucidated. One class of non-coding RNAs is long non-coding RNAs or lncRNAs, many of which have been identified to play a range of roles in transcription and translation. While the clinical importance of the majority of lncRNAs have yet to be identified, it is puzzling that a large number of disease-associated genetic variations are seen in lncRNA genes. The 8q24.21 locus is rich in lncRNAs and very few protein-coding genes are located in this region. Interestingly, the 8q24.21 region is also a hot spot for genetic variants associated with an increased risk of cancer. Research focusing on the lncRNAs in this area of the genome has indicated clinical relevance of lncRNAs in different cancers. In this review, we summarise the lncRNAs in the 8q24.21 region with respect to their role in cancer and discuss the potential impact of cancer-associated genetic polymorphisms on the function of lncRNAs in initiation and progression of cancer.

C-Myc-activated long non-coding RNA PVT1 enhances the proliferation of cervical cancer cells by sponging miR-486-3p

Cervical cancer is one of the most prevalent gynecological malignancies. Although the functions of long non-coding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) and c-Myc in tumorigenesis have been acknowledged, the roles of c-Myc and lncRNA-PVT1 in the proliferation of cervical cancer are still unclear. Our study is designed to demonstrate the regulatory network involving c-Myc and lncRNA-PVT1 in cervical cancer. Quantitative real-time PCR and western blot assays were performed in our research to estimate the expression levels of RNA and proteins. CCK8 assays were applied to demonstrate the viability of HeLa and SiHa cells. Immunofluorescence assay was then used to investigate the co-localization of lncRNA-PVT1 and miR-486-3p. Binding of c-Myc to the promoter region of PVT1 was identified by ChIP-assay. Functionally, upregulation of lncRNA-PVT1 enhanced the proliferation and viability of cervical cancer cells. Mechanistically, lncRNA-PVT1 sponged miR-486-3p and released its repression of extracellular matrix protein 1. Besides, c-Myc functioned as an activator of lncRNA-PVT1 and upregulated its expression by binding to the promoter of PVT1 in cervical cancer cells. lncRNA-PVT1 was upregulated by c-Myc and thus enhanced the proliferation of cervical cancer cells by sponging miR-486-3p.

Tumor suppressing effects of tristetraprolin and its small double-stranded RNAs in bladder cancer

Bladder cancer (BCa) is a common malignant tumor of urinary system with few treatments, so more useful therapeutic targets are still needed. Antitumor effects of tristetraprolin (TTP) have been explored in many type tumors, but its roles in bladder cancer are still unknown until now. In this study, public expression profiles and tissue microarray analysis showed that TTP mRNA and protein levels decreased in BCa relative to the normal bladder tissue. To explore biological functions of TTP in BCa, 488 TTP target genes, which could be both suppressed and bound by TTP, were identified by comprehensively analyzing publicly available high-throughput data obtained from Gene Expression Omnibus (GEO). Gene enrichment analysis showed that these genes were enriched in pathways such as cell cycle, epithelial to mesenchymal transition (EMT), and Wnt signaling. Clustering analysis and gene set variation analysis indicated that patients with high expression of TTP target genes had poorer prognosis and stronger tumor proliferation ability relative to the BCa patients with low expression of TTP target genes. In vitro experiments validated that TTP could suppress proliferation, migration, and invasiveness of BCa cells. And TTP could suppress mRNA expression of cyclin-dependent kinase 1 (CDK1) in BCa cells by target its 3' UTR. Then, we identified a new small double-stranded RNA (dsRNA) named dsTTP-973 which could increase TTP expression in BCa cells, in vivo and in vitro experiments revealed that dsTTP-973 could suppress aggressiveness of BCa. In conclusion, TTP played a role of tumor suppressor gene in BCa like other tumors, and its dsRNA named dsTTP-973 could induce TTP expression in BCa and suppress aggressiveness of BCa. With the help of materials science, dsTTP-973 may become a potential treatment for BCa in the future.

LncRNA SNHG12 regulates the radiosensitivity of cervical cancer through the miR-148a/CDK1 pathway

Background

Radiation resistance is a major obstacle to the prognosis of cervical cancer (CC) patients. Many studies have confirmed that long non-coding RNAs (lncRNAs) are involved in the regulation of radiosensitivity of cancers. However, whether small nucleolar RNA host gene 12 (SNHG12) regulates the radiosensitivity of CC remains unknown.

Methods

Quantitative real-time polymerase chain reaction was used to measure the expression levels of SNHG12 and microRNA-148a (miR-148a). The radiosensitivity of cells was evaluated by clonogenic assay. Flow cytometry and caspase-3 activity assay were performed to assess the apoptosis ability and cell cycle distribution of cells. Besides, dual-luciferase reporter and RNA immunoprecipitation assay were used to verify the interaction between miR-148a and SNHG12 or cyclin-dependent kinase 1 (CDK1). Also, the protein levels of CDK1, CCND1 and γ-H2AX were detected by western blot analysis. Furthermore, in vivo experiments were conducted to verify the effect of SNHG12 on CC tumor growth. Ki-67 and TUNEL staining were employed to evaluate the proliferation and apoptosis rates in vivo. The hematoxylin and eosin (HE) staining were employed to evaluate the tumor cell morphology.

Results

SNHG12 was upregulated in CC tissues and cells, and its knockdown improved the radiosensitivity by promoting the radiation-induced apoptosis and cell cycle arrest of CC cells. Also, miR-148a could be sponged by SNHG12 and could target CDK1. MiR-148a inhibitor or CDK1 overexpression could invert the promotion effect of silenced-SNHG12 on CC radiosensitivity. Meanwhile, SNHG12 interference reduced the tumor growth of CC, increased miR-148a expression, and inhibited CDK1 level in vivo.

Conclusion

LncRNA SNHG12 promoted CDK1 expression to regulate the sensitivity of CC cells to radiation through sponging miR-148a, indicating that SNHG12 could be used as a potential biomarker to treat the radiotherapy resistance of CC patients.

MicroRNAs and target molecules in bladder cancer

Bladder cancer (BC) is considered as one of the most common malignant tumors in humans with complex pathogenesis including gene expression variation, protein degradation, and changes in signaling pathways. Many studies on involved miRNAs in BC have demonstrated that they could be used as potential biomarkers in the prognosis, response to treatment, and screening before the cancerous phenotype onset. MicroRNAs (miRNAs) regulate many cellular processes through their different effects on special targets along with modifying signaling pathways, apoptosis, cell growth, and differentiation. The diverse expression of miRNAs in cancerous tissues could mediate procedures leading to the oncogenic or suppressor behavior of certain genes in cancer cells. Since a specific miRNA may have multiple targets, an mRNA could also be regulated by multiple miRNAs which further demonstrates the actual role of miRNAs in cancer. In addition, miRNAs can be utilized as biomarkers in some cancers that cannot be screened in the early stages. Hence, finding blood, urine, or tissue miRNA biomarkers by novel or routine gene expression method could be an essential step in the prognosis and control of cancer. In the present review, we have thoroughly evaluated the recent findings on different miRNAs in BC which can provide comprehensive information on better understanding the role of diverse miRNAs and better decision making regarding the new approaches in the diagnosis, prognosis, prevention, and treatment of BC.

Knockdown of lncRNA ZNRD1-AS1 inhibits progression of bladder cancer by regulating miR-194 and ZEB1

BACKGROUND

Bladder cancer (BC) is a common urinary neoplasm with high incidence worldwide. Long noncoding RNA zinc ribbon domain containing 1 antisense RNA 1 (ZNRD1-AS1) has been reported to be upregulated in BC. However, the exact role of ZNRD1-AS1 as well as its mechanism remains poorly understood.

METHODS

Zinc ribbon domain containing 1 antisense RNA 1, and its potential downstream genes microRNA-194 (miR-194) and zinc finger E-box binding homeobox 1 (ZEB1) levels were detected via quantitative real-time polymerase chain reaction or western blot. Cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) were detected to assess the influences of ZNRD1-AS1, miR-194 and ZEB1 on BC cells by colony formation, cell counting kit-8 (CCK-8), transwell analysis or western blot. The relationship between miR-194 and ZNRD1-AS1 or ZEB1 was analyzed by luciferase activity analysis. The xenograft experiment was performed to assess the function of ZNRD1-AS1 in vivo.

RESULTS

Zinc ribbon domain containing 1 antisense RNA 1level was upregulated in BC. ZNRD1-AS1 silence repressed proliferation, migration, invasion and EMT in BC cells. MiR-194 was identified as a target of ZNRD1-AS1, and miR-194 upregulation repressed proliferation, migration, invasion, and EMT by ZNRD1-AS1 sponging. ZEB1 was targeted via miR-194 and its interference impeded proliferation, migration, invasion, and EMT. Moreover, ZNRD1-AS1 regulated ZEB1 expression via miR-194. Besides, inhibition of ZNRD1-AS1 attenuated tumor growth by miR-194/ZEB1 axis in vivo.

CONCLUSION

Knockdown of ZNRD1-AS1 suppressed BC cell development in vitro and in vivo via targeting miR-194 to regulate ZEB1, indicating a novel avenue for treatment of BC.

Upregulation of lncRNA plasmacytoma variant translocation 1 predicts poor prognosis in patients with muscle-invasive bladder cancer

LncRNA plasmacytoma variant translocation 1 (PVT1) has been recognized as an oncogenic lncRNA, which participates in the migration and invasion of many kinds of cancer cells and the development of cancers. In the present study, we explored its clinical significance and prognostic value in muscle invasive bladder cancer (MIBC).A total of 98 MIBC patients' samples were collected, who had undergone radical cystectomy from the March 2013 to December 2018. The associations between PVT1 expression and clinical data were calculated using the Chi-test. Overall survival curves were determined by the Kaplan-Meier technique and contrasted via log-rank test. We utilized univariate and multivariate Cox proportional hazard models to examine the HR and 95% CI.The expression levels of PVT1 were significantly higher in MIBC tissues than that in normal bladder tissues (P < .001). PVT1 expression was significantly correlated with tumor grade (P = .009), margin (P = .002), T stage (P = .02), and lymph node metastasis (P < .001). MIBC patients with high PVT1 expression level had shorter overall survival than those with low PVT1 expression level (log-rank test, P = .004). Multivariate Cox regression analysis showed that PVT1 expression level (HR = 2.381, 95% CI: 1.821-7.012, P = .014) was an independent factor in predicting the overall survival of MIBC patients.In summary, increased PVT1 expression in MIBC patients is correlated with a higher MIBC stage and is significantly associated with poor prognosis for MIBC patients, which may provide new insights into new therapeutic strategy and postoperative intervention against bladder cancer.

LncRNA OIP5-AS1 promotes the malignancy of pancreatic ductal adenocarcinoma via regulating miR-429/FOXD1/ERK pathway

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC), a subtype of pancreatic cancer, is a malignant tumor with unfavorable prognosis. Despite accumulating researches have made efforts on finding novel therapeutic methods for this disease, the underlying mechanism of long non-coding RNAs (lncRNAs) remains elusive. OIP5 antisense RNA 1 (OIP5-AS1) has been reported to play important role in the occurrence and development of multiple human cancers. This study was aimed at unveiling the regulatory role of OIP5-AS1 in PDAC.

METHODS

RT-qPCR analysis revealed the OIP5-AS1 expression in PDAC tissues and adjacent normal ones. Kaplan-Meier method was applied to analyze the overall survival of patients with high or low level of OIP5-AS1. Gain- or loss-of function assays were performed to assess the effects of OIP5-AS1 knockdown on cell functions, including proliferation, migration and EMT process. Mechanism experiments, such as luciferase reporter and RNA pull-down assays proved the interaction between OIP5-AS1 and miR-429 as well as that between miR-429 and FOXD1.

RESULTS

OIP5-AS1 was up-regulated in PDAC tissues and cell lines, and high level of OIP5-AS1 indicated poor prognosis in PDAC patients. OIP5-AS1 knockdown hindered cell proliferation, migration and epithelial-mesenchymal transition (EMT) process, while overexpression of OIP5-AS1 caused the opposite results. OIP5-AS1 activated ERK pathway through up-regulating forkhead box D1 (FOXD1) expression by sponging miR-429. Furthermore, OIP5-AS1 facilitated cell growth in vivo.

CONCLUSION

OIP5-AS1 exerted oncogenic function in PDAC cells through targeting miR-429/FOXD1/ERK pathway.

Identification of key candidate genes and pathways in anaplastic thyroid cancer by bioinformatics analysis

BACKGROUND

Anaplastic thyroid carcinoma (ATC) is a refractory and poor prognosis tumor Present study aimed to investigate the underlying biological functions and pathways involved in the development of ATC and to identify potential hub genes and candidate biomarkers of ATC.

MATERIALS AND METHODS

Bioinformatics analyses were performed to identify the differentially expressed genes (DEGs) between ATC tissue samples and adjacent normal tissue samples. Protein-protein interaction (PPI) networks of the DEGs were constructed using Search Tool for the Retrieval of Interacting Genes online tool and Cytoscape software and divided into sub-networks using the Molecular Complex Detection (MCODE) plug-in. DEGs in each module was analyzed by enrichment analysis of the KEGG Orthology Based Annotation System (KOBAS) web software version 3.0. Eventually, the hub genes from bioinformatics analysis were verified by qRT-PCR assay in different ATC cell lines.

RESULTS

Thirty hub genes were selected and three modules were built by the Cytoscape software from the PPI network. Seven genes (CDK1, CCNB2, BUB1B, CDC20, RRM2, CHEK1 and CDC45) were screened from thirty hub genes. Enrichment analysis showed that these hub genes were primarily accumulated in 'cell cycle', 'p53 signaling pathway', 'viral carcinogenesis', 'pyrimidine metabolism' and 'ubiquitin mediated proteolysis'. The results of qRT-PCR indicated that seven hub genes were unregulated in three ATC cell lines compared with normal thyroid gland cell.

CONCLUSIONS

These findings suggest that CDK1, CCNB2, BUB1B, CDC20, RRM2, CHEK1 and CDC45 may serve as novel diagnosis biomarkers and potential therapeutic target for ATC.

Identification of Key Biomarkers in Bladder Cancer: Evidence from a Bioinformatics Analysis

Bladder cancer (BCa) is one of the most common malignancies and has a relatively poor outcome worldwide. However, the molecular mechanisms and processes of BCa development and progression remain poorly understood. Therefore, the present study aimed to identify candidate genes in the carcinogenesis and progression of BCa. Five GEO datasets and TCGA-BLCA datasets were analyzed by statistical software R, FUNRICH, Cytoscape, and online instruments to identify differentially expressed genes (DEGs), to construct protein‒protein interaction networks (PPIs) and perform functional enrichment analysis and survival analyses. In total, we found 418 DEGs. We found 14 hub genes, and gene ontology (GO) analysis revealed DEG enrichment in networks and pathways related to cell cycle and proliferation, but also in cell movement, receptor signaling, and viral carcinogenesis. Compared with noncancerous tissues, TPM1, CRYAB, and CASQ2 were significantly downregulated in BCa, and the other hub genes were significant upregulated. Furthermore, MAD2L1 and CASQ2 potentially play a pivotal role in lymph nodal metastasis. CRYAB and CASQ2 were both significantly correlated with overall survival (OS) and disease-free survival (DFS). The present study highlights an up to now unrecognized possible role of CASQ2 in cancer (BCa). Furthermore, CRYAB has never been described in BCa, but our study suggests that it may also be a candidate biomarker in BCa.

Long non-coding RNA in bladder cancer

Bladder cancer (BC) is the ninth most common malignant disease and ranks fourteenth in cancer mortality worldwide. Moreover, among cancers, the incidence and mortality of BC in males increased to the 6th and 9th place, respectively. The overall survival (OS) declines dramatically as the cancer progresses, especially when urothelial cells transition from noninvasive to invasive. It is well known that epithelial cells can acquire invasive properties and a propensity to metastasize through the epithelial-to-mesenchymal transition (EMT) process in tumourigenesis and progression. However, the potential molecular mechanisms and key pathways are still unclear. As the sequencing technology advances, long non-coding RNAs (lncRNAs) have been proven to play an important role in regulating biological processes and cellular pathways. Here, we reviewed important lncRNAs, such as H19, UCA1 and MALAT1, that participate in the malignant phenotype of BC and regulate EMT signalling networks in the invasion-metastasis cascade during BC development. We further discuss MALAT1, PCAT-1 and SPRY4-IT1, and also urine and blood exosomal H19 and PTENP as potential noninvasive biomarkers. Moreover, antisense oligonucleotides (ASOs) and a double-stranded DNA plasmid (BC-819) have been designed for use in preclinical cancer models and clinical trials in patients. Therefore, the results of investigations have gradually prompted the utility of lncRNAs.

Knockdown of long non-coding RNA plasmacytoma variant translocation 1 inhibits cell proliferation while promotes cell apoptosis via regulating miR-486-mediated CDK4 and BCAS2 in multiple myeloma

AIMS

This study aimed to investigate the effect of long non-coding RNA-plasmacytoma variant translocation 1 (lnc-Pvt1) knockdown on regulating cell proliferation and apoptosis, and to explore its molecular mechanism in multiple myeloma (MM).

METHODS

Lnc-Pvt1 expression was detected in MM cell lines (NCI-H929, U-266, LP-1 and RPMI-8226 cell lines) and human normal plasma cells. In U-266 cells and LP-1 cells, control shRNA and lnc-Pvt1 shRNA plasmids were transferred. Rescue experiments were further performed by transfection of lnc-Pvt1 shRNA alone and lnc-Pvt1 shRNA and miR-486 shRNA plasmids. Cells proliferation, apoptosis, RNA expression, and protein expression were determined by cell counting kit-8, annexin V-FITC-propidium iodide, quantitative polymerase chain reaction, and Western blot assays, respectively.

RESULTS

Lnc-Pvt1 expression was increased in MM cell lines (NCI-H929, U-266 and LP-1 cell lines) compared with human normal plasma cells. In U-266 cells, lnc-Pvt1 shRNA suppressed cell proliferation while enhanced cell apoptosis compared with control shRNA. Also, lnc-Pvt1 shRNA increased miR-486 expression compared with control shRNA. Further rescue experiment revealed that miR-486 shRNA did not change lnc-Pvt1 level, but increased CDK4 and BCAS2 expressions in lnc-Pvt1 knockdown-treated cells. In addition, miR-486 shRNA promoted cell proliferation while inhibited cell apoptosis in lnc-Pvt1 knockdown-treated cells. These results were further validated in LP-1 cells.

CONCLUSIONS

Lnc-Pvt1 knockdown inhibits cell proliferation and induces cell apoptosis through potentially regulating miR-486-mediated CDK4 and BCAS2 in MM.