Crosstalk between the lncRNA UCA1 and microRNAs in cancer

Long non-coding RNAs in non-small cell lung cancer: implications for preventing therapeutic resistance

Lung cancer has the highest mortality and morbidity rates among all cancers worldwide. Despite many complex treatment options, including radiotherapy, chemotherapy, targeted drugs, immunotherapy, and combinations of these treatments, efficacy is low in cases of resistance to therapy, metastasis, and advanced disease, contributing to low overall survival. There is a pressing need for the discovery of novel biomarkers and therapeutic targets for the early diagnosis of lung cancer and to determine the efficacy and outcomes of drug treatments. There is now substantial evidence for the diagnostic and prognostic value of long noncoding RNAs (lncRNAs). This review briefly discusses recent findings on the roles and mechanisms of action of lncRNAs in the responses to therapy in non-small cell lung cancer.

The HOXD9-mediated PAXIP1-AS1 regulates gastric cancer progression through PABPC1/PAK1 modulation

Long non-coding RNAs (lncRNAs) have been functionally characterised in various diseases. LncRNA PAX-interacting protein 1-antisense RNA 1 (PAXIP1-AS1) has reportedly been associated with cancer development. However, its role in gastric cancer (GC) remains poorly understood. Here, we showed that PAXIP1-AS1 was transcriptionally repressed by homeobox D9 (HOXD9) and was significantly downregulated in GC tissues and cells. Decreased expression of PAXIP1-AS1 was positively correlated with tumour progression, while PAXIP1-AS1 overexpression inhibited cell growth and metastasis both in vitro and in vivo. PAXIP1-AS1 overexpression significantly attenuated HOXD9-enhanced epithelial-to-mesenchymal transition (EMT), invasion and metastasis in GC cells. Poly(A)-binding protein cytoplasmic 1 (PABPC1), an RNA-binding protein, was found to enhance the stability of PAK1 mRNA, leading to EMT progress and GC metastasis. PAXIP1-AS1 was found to directly bind to and destabilise PABPC1, thereby regulating EMT and metastasis of GC cells. In summary, PAXIP1-AS1 suppressed metastasis, and the HOXD9/PAXIP1-AS1/PABPC1/PAK1 signalling axis may be involved in the progression of GC.

Non-coding RNA mediates endoplasmic reticulum stress-induced apoptosis in heart disease

Apoptosis is a complex and highly self-regulating form of cell death, which is an important cause of the continuous decline in ventricular function and is widely involved in the occurrence and development of heart failure, myocardial infarction, and myocarditis. Endoplasmic reticulum stress plays a crucial role in apoptosis-inducing. Accumulation of misfolded or unfolded proteins causes cells to undergo a stress response called unfolded protein response (UPR). UPR initially has a cardioprotective effect. Nevertheless, prolonged and severe ER stress will lead up to apoptosis of stressed cells. Non-coding RNA is a type of RNA that does not code proteins. An ever-increasing number of studies have shown that non-coding RNAs are involved in regulating endoplasmic reticulum stress-induced cardiomyocyte injury and apoptosis. In this study, the effects of miRNA and LncRNA on endoplasmic reticulum stress in various heart diseases were mainly discussed to clarify their protective effects and potential therapeutic strategies for apoptosis.

HERVs and Cancer-A Comprehensive Review of the Relationship of Human Endogenous Retroviruses and Human Cancers

Genomic instability and genetic mutations can lead to exhibition of several cancer hallmarks in affected cells such as sustained proliferative signaling, evasion of growth suppression, activated invasion, deregulation of cellular energetics, and avoidance of immune destruction. Similar biological changes have been observed to be a result of pathogenic viruses and, in some cases, have been linked to virus-induced cancers. Human endogenous retroviruses (HERVs), once external pathogens, now occupy more than 8% of the human genome, representing the merge of genomic and external factors. In this review, we outline all reported effects of HERVs on cancer development and discuss the HERV targets most suitable for cancer treatments as well as ongoing clinical trials for HERV-targeting drugs. We reviewed all currently available reports of the effects of HERVs on human cancers including solid tumors, lymphomas, and leukemias. Our review highlights the central roles of HERV genes, such as gag, env, pol, np9, and rec in immune regulation, checkpoint blockade, cell differentiation, cell fusion, proliferation, metastasis, and cell transformation. In addition, we summarize the involvement of HERV long terminal repeat (LTR) regions in transcriptional regulation, creation of fusion proteins, expression of long non-coding RNAs (lncRNAs), and promotion of genome instability through recombination.

Lenvatinib resistance mechanism and potential ways to conquer

Lenvatinib (LVN) has been appoved to treat advanced renal cell carcinoma, differentiated thyroid carcinoma, hepatocellular carcinoma. Further other cancer types also have been tried in pre-clinic and clinic without approvation by FDA. The extensive use of lenvastinib in clinical practice is sufficient to illustrate its important therapeutic role. Although the drug resistance has not arised largely in clinical, the studies focusing on the resistance of LVN increasingly. In order to keep up with the latest progress of resistance caused by LVN, we summerized the latest studies from identify published reports. In this review, we found the latest report about resistance caused by lenvatinib, which were contained the hotspot mechanism such as the epithelial-mesenchymal transition, ferroptosis, RNA modification and so on. The potential ways to conquer the resistance of LVN were embraced by nanotechnology, CRISPR technology and traditional combined strategy. The latest literature review of LVN caused resistance would bring some ways for further study of LVN. We call for more attention to the pharmacological parameters of LVN in clinic, which was rarely and would supply key elements for drug itself in human beings and help to find the resistance target or idea for further study.

The employment of vaccinia virus for colorectal cancer treatment: A review of preclinical and clinical studies

Colorectal cancer (CRC) is one of the leading malignancies that causes death worldwide. Cancer vaccines and oncolytic immunotherapy bring new hope for patients with advanced CRC. The capability of vaccinia virus (VV) in carrying foreign genes as antigens or immunostimulatory factors has been demonstrated in animal models. VV of Wyeth, Western Reserve, Lister, Tian Tan, and Copenhagen strains have been engineered for the induction of antitumor response in multiple cancers. This paper summarized the preclinical and clinical application and development of VV serving as cancer vaccines and oncolytic vectors in CRC treatment. Additionally, the remaining challenges and future direction are also discussed.

The role of long noncoding RNAs in therapeutic resistance in cervical cancer

Cervical cancer is one of the common tumors and often causes cancer-related death in women. Chemotherapy is a common cancer therapy, which displays a pivotal clinical benefit for cancer patients. However, chemoresistance becomes a big obstacle for failure of treatment in cancer patients. Recently, long noncoding RNAs (lncRNAs) have been identified to regulate drug resistance in human cancers, including cervical cancer. In this review, we describe the role of lncRNAs in regulation of chemotherapeutic resistance in cervical cancer. We also discuss the molecular mechanisms of lncRNA-mediated drug resistance in cervical cancer. Moreover, we describe that targeting lncRNAs could reverse drug resistance in cervical cancer. Therefore, lncRNAs could become effective therapeutic targets and chemotherapeutic sensitizers for cervical cancer patients.

Regulation of the Key Epithelial Cancer Suppressor miR-124 Function by Competing Endogenous RNAs

A decrease in the miR-124 expression was observed in various epithelial cancers. Like a classical suppressor, miR-124 can inhibit the translation of multiple oncogenic proteins. Epigenetic mechanisms play a significant role in the regulation of miR-124 expression and involve hypermethylation of the MIR-124-1/-2/-3 genes and the effects of long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) according to the model of competing endogenous RNAs (ceRNAs). More than 40 interactomes (lncRNA/miR-124/mRNA) based on competition between lncRNAs and mRNAs for miR-124 binding have been identified in various epithelial cancers. LncRNAs MALAT1, NEAT1, HOXA11-AS, and XIST are the most represented in these axes. Fourteen axes (e.g., SND1-IT1/miR-124/COL4A1) are involved in EMT and/or metastasis. Moreover, eight axes (e.g., OIP5-AS1/miR-124-5p/IDH2) are involved in key pathways, such as Wnt/b-catenin, E2F1, TGF-β, SMAD, ERK/MAPK, HIF-1α, Notch, PI3K/Akt signaling, and cancer cell stemness. Additionally, 15 axes impaired patient survival and three axes reduced chemo- or radiosensitivity. To date, 14 cases of miR-124 regulation by circRNAs have been identified. Half of them involve circHIPK3, which belongs to the exonic ecircRNAs and stimulates cell proliferation, EMT, autophagy, angiogenesis, and multidrug resistance. Thus, miR-124 and its interacting partners may be considered promising targets for cancer therapy.

Single-cell RNA sequencing highlights the functional role of human endogenous retroviruses in gallbladder cancer

Background

Gallbladder cancer (GBC), the most common malignancy of the biliary tract, shows late diagnosis and low survival rate and requires continued search for new diagnostic biomarkers and therapeutic targets. Human endogenous retroviruses (HERVs) are specifically prone to be reactivated in diverse cancers and are implicated in cancer progression and immunotherapy.

Methods

Single-cell RNA sequencing was performed on tumor tissues and paired adjacent tissues from 4 GBC patients. Dual-luciferase reporter assay was applied to measure enhancer activity of HERV sequences.

Findings

We dissected the cellular diversity and described the HERV transcriptomic landscape for GBC. We found that HERVs were transcribed in a cell type-specific manner and different HERV families were associated with diverse biological effects. HERVs could function as enhancers, presumably causing altered expression of neighboring genes. The transcription level of HERVH was gradually elevated with the malignant transformation of epithelial cells, suggesting HERVH may be a potential early diagnostic biomarker of GBC. HHLA2, a newly emerging immune checkpoint, was derived by HERVH, exhibited an expressional correlation with HERVH, and was identified as a promising target for immunotherapy.

Interpretation

Exploring the transcriptional landscape and potential functional impact of HERVs highlights the important role of HERVs in GBC and provides a fresh perspective on managing GBC.

Funding

This study was supported by the National Natural Science Foundation of China (31970176, 81972256) and the research grants from the Innovation Capacity Building Project of Jiangsu province (BM2020019).

LINC00092 Modulates Oxidative Stress and Glycolysis of Breast Cancer Cells via Pyruvate Carboxylase-Mediated AKT/mTOR Pathway

Background

The discovery of noncoding RNAs (ncRNAs) offers new options for cancer-targeted therapy. This study is aimed at exploring the regulatory function of LINC00092 on breast cancer (BC) oxidative stress and glycolysis, along with internal mechanism concerning pyruvate carboxylase (PC).

Methods

Bioinformatics analysis was used to explore LINC00092 (or friend leukemia virus integration 1 (FLI1)) expression on BC progression, as well as oxidative stress and glycolysis in BC. After LINC00092 overexpression or silence, BC cell viability, proliferation, migration, invasion, oxidative stress, glycolysis, and AKT/mTOR pathway were detected. Following 2-DG, SC79, or MK2206 treatment, effects of LINC00092 on BC cells were measured. Moreover, regulatory activity of LINC00092 in PC expression was analyzed. Whether PC participated in the modulation of LINC00092 on BC cell functions was explored.

Results

LINC00092 was lowly expressed in BC and negatively related to BC progression. FLI1 bound to LINC00092 promoter to positively modulate LINC00092. LINC00092 overexpression inhibited BC cell proliferation, migration, invasion, oxidative stress, glycolysis, and AKT/mTOR pathway and likewise suppressed BC growth in vivo. Silence of LINC00092 had opposite influences. 2-DG partially reversed the LINC00092 silence-resulted increase of BC cell proliferation. SC79 alleviated the function of LINC00092 overexpression on BC cell functions. MK2206 had the contrary influence of SC79. Besides, LINC00092 bound to PC to modulate ubiquitination degradation of PC protein. PC took part in the influences of LINC00092 on BC cell functions.

Conclusions

LINC0092 modulates oxidative stress and glycolysis of BC cells via the PC-mediated AKT/mTOR pathway, which is possibly a target for BC diagnosis and therapy.

What is beyond LncRNAs in breast cancer: A special focus on colon cancer-associated Transcript-1 (CCAT-1)

Long non-coding RNAs (LncRNAs) play a vital role in the process of malignant transformation. In breast cancer (BC), lncRNAs field is currently under intensive investigations. Yet, the role of lncRNAs as promising diagnostic and/or prognostic biomarkers and as therapeutic target/tool among BC patients still needs a special focus from the biomedical scientists. In BC, triple negative breast cancer patients (TNBC) are the unlucky group as they are always represented with the worst prognosis and the highest mortality rates. For that reason, a special focus on TNBC and associated lncRNAs was addressed in this review. Colon cancer-associated transcript 1 (CCAT-1) is a newly discovered oncogenic lncRNA that has been emerged as a vital biomarker for diagnosis, prognosis and therapeutic interventions in multiple malignancies and showed differential expression among TNBC patients. In this review, the authors shed the light onto the general role of lncRNAs in BC and the specific functional activities, molecular mechanisms, competing endogenous ncRNA role of CCAT-1 in TNBC.

Revealing the role of miRNA-489 as a new onco-suppressor factor in different cancers based on pre-clinical and clinical evidence

Recently, microRNAs (miRNAs) have shown to be potential therapeutic, diagnostic and prognostic targets in disease therapy. These endogenous non-coding RNAs contribute to regulation of different cellular events that are necessary for maintaining physiological condition. Dysregulation of miRNAs is correlated with development of various pathological events such as neurological disorders, cardiovascular diseases, and cancer. miRNA-489 is a new emerging miRNA and studies are extensively investigating its role in pathological conditions. Herein, potential function of miRNA-489 as tumor-suppressor in various cancers is described. miRNA-489 is able to sensitize cancer cells into chemotherapy by disrupting molecular pathways involved in cancer growth such as PI3K/Akt, and induction of apoptosis. The PROX1 and SUZ12 as oncogenic pathways, are affected by miRNA-489 in suppressing metastasis of cancer cells. Wnt/β-catenin as an oncogenic factor ensuring growth and malignancy of tumors is inhibited via miRNA-489 function. For enhancing drug sensitivity of tumors, restoring miRNA-489 expression is a promising strategy. The lncRNAs can modulate miRNA-489 expression in tumors and studies about circRNA role in miRNA-489 modulation should be performed. The expression level of miRNA-489 is a diagnostic tool for tumor detection. Besides, down-regulation of miRNA-489 in tumors provides unfavorable prognosis.

Stabilization of UCA1 by N6-methyladenosine RNA methylation modification promotes colorectal cancer progression

Background

UCA1 is frequently upregulated in a variety of cancers, including CRC, and it can play an oncogenic role by various mechanisms. However, how UCA1 is regulated in cancer is largely unknown. In this study, we aimed to determine whether RNA methylation at N6-methyladenosine (m6A) can impact UCA1 expression in colorectal cancer (CRC).

Methods

qRT-PCR was performed to detect the level of UCA1 and IGF2BP2 in CRC samples. CRISPR/Cas9 was employed to knockout (KO) UCA1, METTL3 and WTAP in DLD-1 and HCT-116 cells, while rescue experiments were carried out to re-express METTL3 and WTAP in KO cells. Immunoprecipitation using m6A antibody was performed to determine the m6A modification of UCA1. In vivo pulldown assays using S1m tagging combined with site-direct mutagenesis was carried out to confirm the recognition of m6A-modified UCA1 by IGF2BP2. Cell viability was measured by MTT and colony formation assays. The expression of UCA1 and IGF2BP2 in TCGA CRC database was obtained from GEPIA (http://gepia.cancer-pku.cn).

Results

Our results revealed that IGF2BP2 serves as a reader for m6A modified UCA1 and that adenosine at 1038 of UCA1 is critical to the recognition by IGF2BP2. Importantly, we showed that m6A writers, METTL3 and WTAP positively regulate UCA1 expression. Mechanically, IGF2BP2 increases the stability of m6A-modified UCA1. Clinically, IGF2BP2 is upregulated in CRC tissues compared with normal tissues.

Conclusion

These results suggest that m6A modification is an important factor contributing to upregulation of UCA1 in CRC tissues.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02288-x.

Hypoxia related long non-coding RNAs in ischemic stroke

With high rates of mortality and disability, stroke has caused huge social burden, and 85% of which is ischemic stroke. In recent years, it is a progressive discovery of long non-coding RNA (lncRNA) playing an important regulatory role throughout ischemic stroke. Hypoxia, generated from reduction or interruption of cerebral blood flow, leads to changes in lncRNA expression, which then influence disease progression. Therefore, we reviewed studies on expression of hypoxia-related lncRNAs and relevant molecular mechanism in ischemic stroke. Considering that hypoxia-inducible factor (HIF) is a crucial regulator in hypoxic progress, we mainly focus on the HIF-related lncRNA which regulates the expression of HIF or is regulated by HIF, further reveal their pathogenesis and adaption after brain ischemia and hypoxia, so as to find effective biomarker and therapeutic targets.

LncRNA as a multifunctional regulator in cancer multi-drug resistance

BACKGROUND

Malignant tumors have become the most dangerous disease in recent years. Chemotherapy is the most effective treatment for this disease; however, the problem of drug resistance has become even more common, which leads to the poor prognosis of patients suffering from cancers. Thus, necessary measures should be taken to address these problems at the earliest. Many studies have demonstrated that drug resistance is closely related to the abnormal expressions of long non-coding RNAs (lncRNAs).

METHODS AND RESULTS

This review aimed to summarize the molecular mechanisms underlying the association of lncRNAs and the development of drug resistance and to find potential strategies for the clinical diagnosis and treatment of cancer drug resistance. Studies showed that lncRNAs can regulate the expression of genes through chromatin remodeling, transcriptional regulation, and post-transcriptional processing. Furthermore, lncRNAs have been reported to be closely related to the occurrence of malignant tumors. In summary, lncRNAs have gained attention in related fields during recent years. According to previous studies, lncRNAs have a vital role in several different types of cancers owing to their multiple mechanisms of action. Different mechanisms have different functions that could result in different consequences in the same disease.

CONCLUSIONS

LncRNAs closely participated in cancer drug resistance by regulating miRNA, signaling pathways, proteins, cancer stem cells, pro- and ant-apoptosis, and autophagy. lncRNAs can be used as biomarkers of the possible treatment target in chemotherapy, which could provide solutions to the problem of drug resistance in chemotherapy in the future.

LncRNA UCA1 promotes development of gastric cancer via the miR-145/MYO6 axis

Background

Long noncoding RNA (lncRNA), urothelial carcinoma-associated 1 (UCA1) is aberrantly expressed in multiple cancers and has been verified as an oncogene. However, the underlying mechanism of UCA1 in the development of gastric cancer is not fully understood. In the present study, we aimed to identify how UCA1 promotes gastric cancer development.

Methods

The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) data were used to analyze UCA1 and myosin VI (MYO6) expression in gastric cancer. Western blot and quantitative real-time PCR (QPCR) were performed to test the expression level of the UCA1/miR-145/MYO6 axis in gastric cancer cell lines and tissues. The roles of the UCA1/miR-145/MYO6 axis in gastric cancer in vitro and in vivo were investigated by CCK-8 assay, flow cytometry, siRNAs, immunohistochemistry, and a mouse xenograft model. The targeted relationship among UCA1, miR-145, and MYO6 was predicted using LncBase Predicted v.2 and TargetScan online software, and then verified by luciferase activity assay and RNA immunoprecipitation.

Results

UCA1 expression was higher but miR-145 expression was lower in gastric cancer cell lines or tissues, compared to the adjacent normal cell line or normal tissues. Function analysis verified that UCA1 promoted cell proliferation and inhibited cell apoptosis in the gastric cancer cells in vitro and in vivo. Mechanistically, UCA1 could bind directly to miR-145, and MYO6 was found to be a downstream target gene of miR-145. miR-145 mimics or MYO6 siRNAs could partly reverse the effect of UCA1 on gastric cancer cells.

Conclusions

UCA1 accelerated cell proliferation and inhibited cell apoptosis through sponging miR-145 to upregulate MYO6 expression in gastric cancer, indicating that the UCA1/miR-145/MYO6 axis may serve as a potential therapeutic target for gastric cancer.

The Functional Role of Long Non-coding RNA UCA1 in Human Multiple Cancers: a Review Study

In various cancers, high-grade tumor and poor survival rate in patients with upregulated lncRNAs UCA1 have been confirmed. Urothelial carcinoma associated 1 (UCA1) is an oncogenic non-coding RNA with a length of more than 200 nucleotides. The UCA1 regulate critical biological processes that are involved in cancer progression, including cancer cell growth, invasion, migration, metastasis, and angiogenesis. So It should not surprise that UCA1 overexpresses in variety of cancers type, including pancreatic cancer, ovarian cancer, gastric cancer, colorectal cancer, breast cancer, prostate cancer, endometrial cancer, cervical cancer, bladder cancer, adrenal cancer, hypopharyngeal cancer, oral cancer, gallbladder cancer, nasopharyngeal cancer, laryngeal cancer, osteosarcoma, esophageal squamous cell carcinoma, renal cell carcinoma, cholangiocarcinoma, leukemia, glioma, thyroid cancer, medulloblastoma, hepatocellular carcinoma and multiple myeloma. In this article, we review the biological function and regulatory mechanism of UCA1 in several cancers and also, we will discuss the potential of its as cancer biomarker and cancer treatment.

Dual relationship between long non-coding RNAs and STAT3 signaling in different cancers: New insight to proliferation and metastasis

Uncontrolled growth and metastasis of cancer cells is an increasing challenge for overcoming cancer, and improving survival of patients. Complicated signaling networks account for proliferation and invasion of cancer cells that need to be elucidated for providing effective cancer therapy, and minimizing their malignancy. Long non-coding RNAs (lncRNAs) are RNA molecules with a length of more than 200 nucleotides. They participate in cellular events, and their dysregulation in a common phenomenon in different cancers. Noteworthy, lncRNAs can regulate different molecular pathways, and signal transducer and activator of transcription 3 (STAT3) is one of them. STAT3 is a tumor-promoting factors in cancers due to its role in cancer proliferation (cell cycle progression and apoptosis inhibition) and metastasis (EMT induction). LncRNAs can function as upstream mediators of STAT3 pathway, reducing/enhancing its expression. This dual relationship is of importance in affecting proliferation and metastasis of cancer cells. The response of cancer cells to therapy such as chemotherapy and radiotherapy is regulated by lncRNA/STAT3 axis. Tumor-promoting lncRNAs including NEAT1, SNHG3 and H19 induces STAT3 expression, while tumor-suppressing lncRNAs such as MEG3, PTCSC3 and NKILA down-regulate STAT3 expression. Noteworthy, upstream mediators of STAT3 such as microRNAs can be regulated by lncRNAs. These complicated signaling networks are mechanistically described in the current review.

Detection of lncRNA by LNA-Based In Situ Hybridization in Paraffin-Embedded Cancer Cell Spheroids

Cancer cell spheroids are considered important preclinical tools to evaluate the efficacy of new drugs. In cancer cell spheroids, the cells assemble and grow in 3D structures with cell contact interactions that are partly impermeable, which leads to central hypoxia and necrosis. The cell spheroids thus possess several features identified in clinical tumors. Not only will the effect and behavior of therapeutic drugs in 3D cell spheroids be affected more similarly than in cells grown on culture plates, but molecular interactions and signaling pathways in cells are also more likely to mimic the in vivo situation. The monitoring of various biomarkers including lncRNAs in 3D cell spheroids is important to assess a potentially induced phenotype in the cells and the effects of drugs. Specifically, for lncRNAs, in situ localization can be done using locked nucleic acid (LNA) probe technology. Here we present a protocol for preparation of cell spheroids for use in LNA probe-based in situ hybridization to study lncRNA expression in paraffin embedded 3D cancer cell spheroids.

HMGB1 regulates SNAI1 during NSCLC metastasis, both directly, through transcriptional activation, and indirectly, in a RSF1-IT2-dependent manner

High-mobility group protein B1 (HMGB1) has important functions in cancer cell proliferation and metastasis. However, the mechanisms of HMGB1 function in non-small-cell lung cancer (NSCLC) remain unclear. This study aimed to investigate the underlying mechanism of HMGB1-dependent tumor cell proliferation and NSCLC metastasis. Firstly, we found high HMGB1 expression in NSCLC and showed that HMBG1 promoted proliferation, migration, and invasion of NSCLC cells. HMGB1 could bind to SNAI1 promoter and activate the expression of SNAI1. In addition, HMGB1 could transcriptionally regulate the lncRNA RSF1-IT2. RSF1-IT2 was found to function as ceRNA, sponging miR-129-5p, which targets SNAI1. Notably, HMGB1 was also identified as a target of miR-129-5p, which indicates the establishment of a positive feedback loop. Consequently, high expression of RSF1-IT2 and SNAI1 was found to closely correlate with tumor progression in both HMGB1-overexpressing xenograft nude mice and patients with NSCLC. Taken together, our findings provide new insights into molecular mechanisms of HMGB1-dependent tumor metastasis. Components of the HMGB1-RSF1-IT2-miR-129-5p-SNAI1 pathway may have a potential as prognostic and therapeutic targets in NSCLC.

Long noncoding RNA SNHG14 promotes the aggressiveness of retinoblastoma by sponging microRNA‑124 and thereby upregulating STAT3

A long noncoding RNA called small nucleolar RNA host gene 14 (SNHG14) has been validated as a key regulator of cellular processes in multiple types of human cancer. However, to the best of our knowledge, the expression status and specific roles of SNHG14 in retinoblastoma (RB) have not been studied. The aims of the present study were to determine the expression status of SNHG14 in RB, assess the effects of SNHG14 on malignant characteristics of RB cells and investigate the mechanisms of action of SNHG14 in RB. SNHG14 expression levels in RB tissue samples and cell lines were measured by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). Cell proliferation, apoptosis, migration and invasion in vitro, and tumor growth in vivo were quantitated by the Cell Counting Kit‑8 assay, flow cytometry, migration and invasion assays, and mouse tumor xenograft experiments, respectively. The target microRNA (miRNA) of SNHG14 was predicted by bioinformatics analysis and was subsequently validated by a luciferase reporter assay, RNA immunoprecipitation (RIP) assay, RT‑qPCR, and western blot analysis. SNHG14 was identified to be significantly overexpressed in RB tissues and cell lines. SNHG14 overexpression was markedly associated with the intraocular international retinoblastoma classification stage, optic nerve invasion, and differentiation grade among patients with RB. The patients in the SNHG14 high‑expression group exhibited shorter overall survival compared with the SNHG14 low‑expression group. Functional analysis revealed that SNHG14 silencing inhibited cell proliferation, migration and invasion, and increased apoptosis in vitro, and decreased tumor growth in vivo. SNHG14 directly interacted with, and functioned as a competing endogenous RNA (ceRNA) of, miR‑124, consequently upregulating signal transducer and activator of transcription 3 (STAT3). miR‑124 inhibition and STAT3 expression recovery attenuated the effects of the SNHG14 silencing on RB cells. In conclusion, SNHG14 served as a ceRNA to upregulate STAT3 by sponging miR‑124. Therefore, targeting the SNHG14/miR‑124/STAT3 pathway may be an effective therapeutic strategy against RB.

LncRNA DANCR Promotes Sorafenib Resistance via Activation of IL-6/STAT3 Signaling in Hepatocellular Carcinoma Cells

Background

Hepatocellular carcinoma (HCC) is one of the major malignancies and the second most common cause of cancer-related death worldwide. Sorafenib, an approved first-line systematic treatment agent for HCC, is capable to effectively improve the survival of patients with advanced HCC. The long-noncoding RNA (lncRNA) differentiation antagonizing non-protein coding RNA (DANCR) has been reported to exert oncogenic functions in several kinds of human cancers. However, the role of lncRNA DANCR in sorafenib resistance in HCC remains unknown.

Methods

The expression levels of DANCR in HCC tissues were detected by qRT-PCR. DANCR overexpression and knockdown models were established and utilized to investigate the functional role of DANCR on sorafenib resistance in HCC cells. The MS2-binding sequences-MS2-binding protein–based RNA immunoprecipitation assay, RNA pull-down and luciferase reporter assay was used to detect the association between DANCR and PSMD10 mRNA. The activation of DANCR transcription mediated by STAT3 was assessed by luciferase reporter and chromatin immunoprecipitation assays.

Results

We found that DANCR was significantly overexpressed in HCC tissues and associated with prognosis of HCC patients. Overexpression and knockdown experiments demonstrated that DANCR promoted sorafenib resistance in HCC cells in vitro and in vivo. Mechanistically, the role of DANCR relied largely on the association with PSMD10. DANCR stabilized PSMD10 mRNA through blocking the repressing effect of several microRNAs on PSMD10. Besides, DANCR activated IL-6/STAT3 signaling via PSMD10. Furthermore, we revealed that DANCR transcription was enhanced by the activation of IL-6/STAT3 signaling, indicating a positive feedback loop of DANCR and IL-6/STAT3 signaling.

Conclusion

Collectively, our study is the first to elucidate the mechanism of DANCR-mediated sorafenib resistance via PSMD10-IL-6/STAT3 signaling axis, which provides a promising target for developing new therapeutic strategy for sorafenib tolerance of HCC.

Long non-coding RNA UCA1 promotes malignant phenotypes of renal cancer cells by modulating the miR-182-5p/DLL4 axis as a ceRNA

Background

Accumulating literatures have indicated that long non-coding RNAs (lncRNAs) are potential biomarkers that play key roles in tumor development and progression. Urothelial cancer associated 1 (UCA1) is a novel lncRNA that acts as a potential biomarker and is involved in the development of cancers. However, the molecular mechanism of UCA1 in renal cancer is still needed to further explore.

Methods

The relative expression level of UCA1 was determined by Real-Time qPCR in a total of 88 patients with urothelial renal cancer and in different renal cancer cell lines. Loss-of-function experiments were performed to investigate the biological roles of UCA1 and miR-182-5p on renal cancer cell proliferation, migration, apoptosis and tumorigenicity. Comprehensive transcriptional analysis, dual-luciferase reporter assay and western blot etc. were performed to explore the molecular mechanisms underlying the functions of UCA1.

Results

In this study, we found that UCA1 was significantly up-regulated in renal cancer. Moreover, increased UCA1 expression was positively correlated with differentiation and advanced TNM stage. Further experiments demonstrated that knockdown of UCA1 inhibited malignant phenotypes and Notch signal path of renal cancer cells, and miR-182-5p was reverse function as UCA1. UCA1 functioned as a miRNA sponge to positively regulate the expression of Delta-like ligand 4(DLL4) through sponging miR-182-5p and subsequently promoted malignant phenotypes of renal cancer cells, thus UCA1 playing an oncogenic role and miR-182-5p as an antioncogenic one in renal cancer pathogenesis.

Conclusion

UCA1-miR-182-5p-DLL4 axis is involved in proliferation and progression of renal cancer. Thus, this study demonstrated that UCA1 plays a critical regulatory role in renal cancer cell and UCA1 may serve as a potential diagnostic biomarker and therapeutic target of renal cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12943-020-1132-x.

lncRNA IGHCγ1 Acts as a ceRNA to Regulate Macrophage Inflammation via the miR-6891-3p/TLR4 Axis in Osteoarthritis

Accumulating data have implicated that long noncoding RNA (lncRNA) plays an important role in osteoarthritis (OA), which may function as a competitive endogenous RNA (ceRNA) of microRNAs (miRNAs). lncRNA IGHCγ1 has been demonstrated to regulate inflammation and autoimmunity. Nonetheless, the altering effect of IGHCγ1 in OA remains unclear. This study is aimed at investigating the mechanism and function of lncRNA IGHCγ1 in OA. CCK-8, EdU, and transwell assays were used to estimate macrophage proliferation and migration. Fluorescence in situ hybridization (FISH) was performed to estimate the local expression of lncRNA IGHCγ1 in macrophages. Luciferase reporter assay was adopted to validate the ceRNA role of IGHCγ1 as miRNA sponge. lncRNA IGHCγ1 was primarily localized in macrophage cytoplasm and upregulated in OA. miR-6891-3p inhibited macrophage proliferation, migration, and inflammatory response by targeting TLR4, while lncRNA IGHCγ1 promoted TLR4 expression by functioning as a ceRNA for miR-6891-3p through the NF-κB signal in macrophages. This study strongly supports that lncRNA IGHCγ1 regulates inflammatory response via regulating the miR-6891-3p/TLR4/NF-κB axis in macrophages.

Assessment of biochemical recurrence of prostate cancer (Review)

The assessment of the risk of biochemical recurrence (BCR) is critical in the management of males with prostate cancer (PC). Over the past decades, a comprehensive effort has been focusing on improving risk stratification; a variety of models have been constructed using PC-associated pathological features and molecular alterations occurring at the genome, protein and RNA level. Alterations in RNA expression (lncRNA, miRNA and mRNA) constitute the largest proportion of the biomarkers of BCR. In this article, we systemically review RNA-based BCR biomarkers reported in PubMed according to the PRISMA guidelines. Individual miRNAs, mRNAs, lncRNAs and multi-gene panels, including the commercially available signatures, Oncotype DX and Prolaris, will be discussed; details related to cohort size, hazard ratio and 95% confidence intervals will be provided. Mechanistically, these individual biomarkers affect multiple pathways critical to tumorigenesis and progression, including epithelial-mesenchymal transition (EMT), phosphatase and tensin homolog (PTEN), Wnt, growth factor receptor, cell proliferation, immune checkpoints and others. This variety in the mechanisms involved not only validates their associations with BCR, but also highlights the need for the coverage of multiple pathways in order to effectively stratify the risk of BCR. Updates of novel biomarkers and their mechanistic insights are considered, which suggests new avenues to pursue in the prediction of BCR. Additionally, the management of patients with BCR and the potential utility of the stratification of the risk of BCR in salvage treatment decision making for these patients are briefly covered. Limitations will also be discussed.

UCA1 long non-coding RNA: An update on its roles in malignant behavior of cancers

The lncRNA urothelial carcinoma-associated 1 (UCA1) is a 1.4 kb long transcript which has been firstly recognized in human bladder cancer cell line. Subsequent studies revealed its over-expression in a wide array of human cancer cell lines and patients' samples. In addition to conferring malignant phenotype to cells, it enhances resistance to conventional anti-cancer drugs. Moreover, transcript levels of this lncRNA have been regarded as diagnostic markers in several cancer types including gastric, bladder and liver cancers. The underlying mechanism of its participation in carcinogenesis has been identified in some cancer types. Sponging tumor suppressor miRNAs, interacting with cancer-promoting signaling pathways and enhancing cell cycle progression are among these mechanisms. Although few studies have shown anti-carcinogenic properties for this lncRNA, the bulk of evidence supports its oncogenic roles. In the current study, we have reviewed the current literature on the role of UCA1 in the carcinogenic process based on the results of in vitro studies, investigations in animal models and assessment of UCA1 expression in clinical samples.