The long non-coding RNA SNHG5 regulates gefitinib resistance in lung adenocarcinoma cells by targetting miR-377/CASP1 axis

An increase in SNHG5 expression is associated with poor cancer prognosis, according to a meta-analysis

BACKGROUND

He long noncoding RNA small nucleolar host RNA 5 (SNHG5) is highly expressed in many cancers, and there is a notable correlation between the elevated expression of SNHG5 and survival outcome in cancer patients. The objective of this study was to conduct a meta-analysis to evaluate the correlation between SNHG5 expression and the clinical outcome of cancer patients.

METHODS

Six relevant electronic databases were exhaustively searched, and, depending on the inclusion and exclusion criteria, appropriate literature was obtained. The Newcastle-Ottawa Scale (NOS) score was utilized to evaluate the quality of the research for every article included, and pertinent data from each study were carefully extracted. Hazard ratios (HRs), odds ratios (ORs) and 95% confidence intervals (CIs) were combined to explore the association of SNHG5 expression levels with cancer prognosis, and sensitivity analyses and assessments of publication bias were also conducted to investigate any possibility in the publication of the studies.

RESULTS

Eleven studies encompassing 721 patients were ultimately collected. When combined, the hazard ratios (HRs) revealed a substantial direct correlation between elevated SNHG5 expression and an unfavourable prognosis for cancer patients (HR = 1.90, 95% CI 0.87-4.15); however, the correlation did not reach statistical significance. Furthermore, high SNHG5 expression was predictive of advanced TNM stage (OR: 1.988, 95% CI 1.205-3.278) and larger tumour size (OR: 1.571, 95% CI 1.090-2.264); moreover, there were nonsignificant relationships between SNHG5 expression and DM (OR: 0.449, 95% CI 0.077-2.630), lymph node metastasis (OR: 1.443, 95% CI 0.709-2.939), histological grade (OR: 2.098, 95% CI 0.910-4.838), depth of invasion (OR: 1.106, 95% CI 0.376-3.248), age (OR: 0.946, 95% CI 0.718-1.247) and sex (OR: 0.762, 95% CI 0.521-1.115).

CONCLUSION

SNHG5 expression is typically increased in the majority of tumour tissues. Elevated SNHG5 expression may indicate poor prognosis in cancer patients. Therefore, SNHG5 is a promising potential therapeutic target for tumours and a reliable prognostic biomarker.

High SNHG expression may predict a poor lung cancer prognosis based on a meta-analysis

BACKGROUND

An increasing number of small nucleolar RNA host genes (SNHGs) have been revealed to be dysregulated in lung cancer tissues, and abnormal expression of SNHGs is significantly correlated with the prognosis of lung cancer. The purpose of this study was to conduct a meta-analysis to explore the correlation between the expression level of SNHGs and the prognosis of lung cancer.

METHODS

A comprehensive search of six related databases was conducted to obtain relevant literature. Relevant information, such as overall survival (OS), progression-free survival (PFS), TNM stage, lymph node metastasis (LNM), and tumor size, was extracted. Hazard ratios (HRs) and 95% confidence intervals (CIs) were pooled to evaluate the relationship between SNHG expression and the survival outcome of lung cancers. Sensitivity and publication bias analyses were performed to explore the stability and reliability of the overall results.

RESULTS

Forty publications involving 2205 lung cancer patients were included in this meta-analysis. The pooled HR and 95% CI values indicated a significant positive association between high SNHG expression and poor OS (HR: 1.890, 95% CI: 1.595-2.185), disease-free survival (DFS) (HR: 2.31, 95% CI: 1.57-3.39) and progression-free survival (PFS) (HR: 2.01, 95% CI: 0.66-6.07). The pooled odds ratio (OR) and 95% CI values indicated that increased SNHG expression may be correlated with advanced TNM stage (OR: 1.509, 95% CI: 1.267-1.799), increase risk of distant lymph node metastasis (OR: 1.540, 95% CI: 1.298-1.828), and large tumor size (OR: 1.509, 95% CI: 1.245-1.829). Sensitivity analysis and publication bias results showed that each result had strong reliability and robustness, and there was no significant publication bias or other bias.

CONCLUSION

Most SNHGs are upregulated in lung cancer tissues, and high expression of SNHGs predicts poor survival outcomes in lung cancer. SNHGs may be potential prognostic markers and promising therapeutic targets.

Advances in long non-coding RNA regulating drug resistance of cancer

Drug resistance is one of the main challenges in cancer treatment. Long non coding RNAs (lncRNAs) play a complex and precise regulatory role in regulating drug resistance of cancer. The common ways of lncRNA regulating drug resistance of cancer involve ATP binding transporter overexpression, abnormal DNA damage response, tumor cell apoptosis, accumulation of epithelial mesenchymal transformation and cancer stem cell formation. Moreover, studies on exosomal lncRNAs regulating cancer drug resistance are developed in recent years. Further study on the role and mechanism of lncRNAs drug resistance in cancer will help clinical cancer treatment program and explore new treatment methods. This paper reviews recent advances in lncRNAs regulating drug resistance of cancer, especially the role of exosomal lncRNAs.

[Research Progress of LncRNA SNHGs in Regulating the Biological Behavior of Non-small Cell Lung Cancer]

Lung cancer is one of the malignant tumors with the highest incidence and mortality rate in China, and its occurrence and development mechanism and treatment methods are the current research focuses. In recent years, the emergence of drugs targeting various tumor driver genes has significantly improved patients' survival and quality of life, setting off a wave of research on new therapeutic targets. Among them, long non-coding RNA (lncRNA) plays a crucial role in the malignant behavior of tumors, which has attracted widespread attention. Shown by a large number of studies, partial members of lncRNA small nucleolar RNA host gene (SNHG) family are aberrantly expressed in many maliglant tumors including non-small cell lung cancer (NSCLC) and participate in cell proliferation, invasion and migration, which may act as a new diagnostic and prognostic biomarker and can be a therapeutic target of NSCLC. In this review, we comprehensively summarize and explore the recent investigation of SNHGs in NSCLC in order to provide new ideas for the diagnosis and treatment of NSCLC.
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MicroRNA-377: A therapeutic and diagnostic tumor marker

Cancer is considered as one of the main causes of human deaths globally. Despite the recent progresses in therapeutic modalities, there is still a high rate of mortality among cancer patients. Late diagnosis in advanced tumor stages is one of the main reasons for treatment failure in cancer patients. Therefore, it is required to suggest the novel strategies for the early tumor detection. MicroRNAs (miRNAs) have critical roles in neoplastic transformation by regulation of cell proliferation, migration, and apoptosis. They are always considered as non-invasive markers due to their high stability in body fluids. Since, all of the miRNAs have tissue-specific functions in different tumors as tumor suppressor or oncogene; it is required to investigate the molecular mechanisms of every miRNA in different tumors to introduce that as a suitable non-invasive diagnostic marker in cancer patients. For the first time in the present review, we discussed the role of miR-377 during tumor progression. It has been reported that miR-377 mainly functions as a tumor suppressor through the regulation of signaling pathways and transcription factors. This review is an important step toward introducing the miR-377 as a novel diagnostic marker as well as a therapeutic target in cancer patients.

LncRNA SNHG5 Suppresses Cell Migration and Invasion of Human Lung Adenocarcinoma via Regulation of Epithelial-Mesenchymal Transition

Long noncoding RNAs (lncRNAs) are gradually being annotated as important regulators of multiple cellular processes. The goal of our study was to investigate the effects of the lncRNA small nucleolar RNA host gene 5 (SNHG5) in lung adenocarcinoma (LAD) and its underlying mechanisms. The findings revealed a substantial drop in SNHG5 expression in LAD tissues, which correlated with clinical-pathological parameters. Transcriptome sequencing analysis demonstrated that the inhibitory effect of SNHG5 was associated with cell adhesion molecules. Moreover, the expression of SNHG5 was shown to be correlated with epithelial-mesenchymal transition (EMT) markers in western blots and immunofluorescence. SNHG5 also had significant effects of antimigration and anti-invasion on LAD cells in vitro. Furthermore, the migration and invasion of A549 cells were suppressed by overexpressed SNHG5 in the EMT progress induced by transforming growth factor β1 (TGF-β1), and this might be due to the inhibition of the expression of EMT-associated transcription factors involving Snail, SLUG, and ZEB1. In LAD tissues, the expression of SNHG5 exhibited a positive association with E-cadherin protein expression but a negative correlation with N-cadherin and vimentin, according to the results of quantitative real-time PCR (qRT-PCR). In summary, the current work demonstrated that the lncRNA SNHG5 might limit cell migration and invasion of LAD cancer via decreasing the EMT process, indicating that SNHG5 might be used as a target for LAD therapeutic methods.

The crucial roles of long noncoding RNA SNHGs in lung cancer

Lung cancer is one of the most common malignant tumors with growing morbidity and mortality worldwide. Several treatments are used to manage lung cancer, including surgery, radiotherapy and chemotherapy, as well as molecular-targeted therapy. However, the current measures are still far from satisfactory. Therefore, the current research should focus on exploring the molecular mechanism and then finding an effective treatment. Interestingly, we and others have embarked on a line of investigations focused on the mechanism of lung cancer. Specifically, lncRNA small nucleolar RNA host gene has been shown to be associated with biological characteristics and therapeutic resistance of lung cancer. In addition, small nucleolar RNA host genes may be used as diagnostic biomarker in the future. Herein, we will provide a brief review demonstrating the importance of small nucleolar RNA host genes in lung cancer, especially non-small cell lung cancer. Although lncRNA has shown a crucial role in tumor-related research, a large number of studies are needed to validate its clinical application in the future.

Discovery of tumor immune infiltration-related snoRNAs for predicting tumor immune microenvironment status and prognosis in lung adenocarcinoma

Lung adenocarcinoma (LUAD) has a high mortality rate and is difficult to diagnose and treat in its early stage. Previous studies have demonstrated that small nucleolar RNAs (snoRNAs) play a critical role in tumor immune infiltration and the development of a variety of solid tumors. However, there have been no studies on the correlation between tumor-infiltrating immune-related snoRNAs (TIISRs) and LUAD. In this study, we filtered six immune-related snoRNAs based on the tissue specificity index (TSI) and expression profile of all snoRNAs between all LUAD cell lines from the Cancer Cell Line Encyclopedia and 21 types of immune cells from the Gene Expression Omnibus database. Further, we performed real-time quantitative polymerase chain reaction (RT-qPCR) to validate the expression status of these snoRNAs on peripheral blood mononuclear cells (PBMCs) and lung cancer cell lines. Next, we developed a TIISR signature based on the expression profiles of snoRNAs from 479 LUAD patients filtered by the random survival forest algorithm. We then analyzed the value of this TIISR signature (TIISR risk score) for assessing tumor immune infiltration, immune checkpoint inhibitor (ICI) treatment response, and the prognosis of LUAD between groups with high and low TIISR risk score. Further, we found that the TIISR risk score groups showed significant differences in biological characteristics and that the risk score could be used to assess the level of tumor immune cell infiltration, thereby predicting prognosis and responsiveness to immunotherapy in LUAD patients.

[Research Progress of Epigenetic Mechanism in Acquired Resistance of Targeted Therapy in Non-small Cell Lung Cancer]

驱动基因阳性的非小细胞肺癌患者能从靶向治疗中获益，但最终都不可避免地出现获得性耐药。表观遗传修饰包括DNA甲基化、组蛋白修饰、非编码RNA调控、染色质重塑等，是非小细胞肺癌靶向治疗获得性耐药的重要机制。近年来，已有研究发现表观遗传修饰的改变可以有效逆转耐药性，靶向治疗联合表观调控可能成为有前景的治疗策略。本文就非小细胞肺癌靶向治疗获得性耐药后表观遗传机制的进展进行了综述，希望为筛选优势人群、克服靶向耐药提供参考和思路。

Down-regulation of lncRNA SNHG5 relieves sepsis-induced acute kidney injury by regulating the miR-374a-3p/TLR4/NF-κB pathway

Sepsis is an acute systemic infectious disease engendered by infectious factors, which can cause the dysfunction of multiple organs, including acute kidney injury (AKI). Recently, more and more researchers are focussing on long noncoding RNA (lncRNA) that is closely associated with the development and progression of various diseases; however, the role and mechanism of lncRNA in sepsis-induced AKI are not fully understood. Here, we found a significant increase in the expression of lncRNA small nuclear RNA host gene 5 (SNHG5) in the serum of patients with sepsis than healthy controls. Similar results were obtained from mouse model of sepsis. Further investigations revealed that knockdown of SNHG5 improves the viability and reduces the rate of apoptosis and the generation of inflammatory cytokines in HK-2 and TCMK-1 cells treated with lipopolysaccharide. Mechanistically, we showed that SNHG5 can combine with microRNA-374a-3p (miR-374a-3p), which inhibits nuclear factor-κB (NF-κB) activity by targeting TLR4. In conclusion, our results demonstrate that SNHG5 may regulate sepsis-induced AKI via the miR-374a-3p/TLR4/NF-κB pathway, therefore providing a new insight into the treatment of this disease.

Long Non-Coding RNA ARAP1-AS1 Facilitates the Progression of Cervical Cancer by Regulating miR-149-3p and POU2F2

BACKGROUND

Emerging research has demonstrated that long non-coding RNAs (lncRNAs) attach great importance to the progression of cervical cancer (CC). LncRNA ARAP1-AS1 was involved in the development of several cancers; however, its role in CC is far from being elucidated.

METHODS

Real-time PCR (RT-PCR) was employed to detect ARAP1-AS1 and miR-149-3p expression in CC samples. CC cell lines (HeLa and C33A cells) were regarded as the cell models. The biological effect of ARAP1-AS1 on cancer cells was measured using CCK-8 assay, colony formation assay, flow cytometry, Transwell assay and wound healing assay in vitro, and subcutaneous xenotransplanted tumor model and tail vein injection model in vivo. Furthermore, interactions between ARAP1-AS1 and miR-149-3p, miR-149-3p and POU class 2 homeobox 2 (POU2F2) were determined by bioinformatics analysis, qRT-PCR, Western blot, luciferase reporter and RNA immunoprecipitation assay, respectively.

RESULTS

The expression of ARAP1-AS1 was enhanced in CC samples, while miR-149-3p was markedly suppressed. Additionally, ARAP1-AS1 overexpression enhanced the viability, migration, and invasion of CC cells. ARAP1-AS1 downregulated miR-149-3p via sponging it. ARAP1-AS1 and miR-149-3p exhibited a negative correlation in CC samples. On the other hand, ARAP1-AS1 enhanced the expression of POU2F2, which was validated as a target gene of miR-149-3p.

CONCLUSION

ARAP1-AS1 was abnormally upregulated in CC tissues and indirectly modulated the POU2F2 expression via reducing miR-149-3p expression. Our study identified a novel axis, ARAP1-AS1/miR-149-3p/POU2F2, in CC tumorigenesis.

Long Noncoding RNA RP11-89K21.1 Interacts with miR-146a/b-5p to Promote Proliferation and Gefitinib Resistance Through Regulating RHPN2 and RhoA/ROCK Pathway in Lung Adenocarcinoma

Background: Long noncoding RNAs (lncRNAs) have major roles in lung adenocarcinoma (LUAD). lncRNA RP11-89K21.1 was reported to be abnormally expressed in LUAD, yet its biological functions in LUAD progression remain unclear. Materials and Methods: The 40 LUAD tissues and pair-matched adjacent normal tissues were enrolled in this study. Quantitative real-time polymerase chain reaction was performed to detect the expression of lncRNA, miRNA, and mRNA in LUAD samples and cell lines. Loss-of-function assays were used to evaluate the effects of RP11-89K21.1 on LUAD cell proliferation and gefitinib resistance. Bioinformatics analysis, luciferase reporter assay, and Western blot were employed to explore the regulatory relationships among RP11-89K21.1, miR-146a/b-5p, and RHPN2. Results: The authors identified that RP11-89K21.1 was highly expressed in LUAD tissues and cell lines. Moreover, upregulated RP11-89K21.1 was strongly associated with unfavorable overall survival of patients with LUAD. Knockdown of RP11-89K21.1 significantly suppressed proliferation and sensitized cell to gefitinib. Mechanistically, RP11-89K21.1 could directly bind miR-146a-5p and miR-146b-5p and decrease their expression to upregulate RHPN2, and subsequently activated RhoA/ROCK pathway. More importantly, overexpression of RHPN2 reversed regulatory effects of RP11-89K21.1 knockdown on cell proliferation and gefitinib resistance. Conclusions: These observations provide new insights into the role of RP11-89K21.1 in regulating LUAD tumorigenesis, suggesting that RP11-89K21.1 is a potential therapeutic target for LUAD treatment.

Long non-coding RNA SNHG5 suppresses the development of acute respiratory distress syndrome by targeting miR-205/COMMD1 axis

Previous studies have reported the important roles of long non-coding RNAs (lncRNAs) in acute respiratory distress syndrome (ARDS). Here, we focus on the role and regulatory mechanism of lncRNA SNHG5 in ARDS. LPS was used to induce mice to establish ARDS model in vivo and to induce A549 cells to establish ARDS model in vitro. qRT-PCR was performed to determine the expressions of SNHG5, miR-205, and inflammatory cytokines. MTT assay was applied to detect cell viability. Dual-luciferase reporter (DLR) assay was performed to test the interactions among SNHG5, miR-205 and COMMD1. Western blot was used to detect the protein expression of COMMD1. Lung injury was evaluated by evaluating the score of lung injury, lung wet/dry weight ratio, and myeloperoxidase (MPO) activity. SNHG5 was downregulated, while miR-205 was upregulated in the serum of ARDS patients and lung tissues of LPS-induced mice. Upregulation of SNHG5 or down-regulation of miR-205 inhibited inflammation and promoted the viability of LPS-induced A549 cells. SNHG5 alleviated the lung injury of ARDS mice. MiR-205 was a target of SNHG5 and inversely correlated with SNHG5. COMMD1 was targeted by miR-205, and was positively regulated by SNHG5. MiR-205 mimics or sh-COMMD1 reversed the promoting effect of SNHG5 on cell viability and the suppressing effect of SNHG5 on inflammation in cellular model of ARDS. Meantime, miR-205 mimics reversed the relieving effect of SNHG5 on lung injury in mouse model of ARDS. SNHG5 acted as a sponge for miR-205 to ameliorate LPS-induced ARDS by regulating COMMD1.

SNHG5/miR-582-5p/RUNX3 feedback loop regulates osteogenic differentiation and apoptosis of bone marrow mesenchymal stem cells

Osteoporosis is one of the most prevailing orthopedic diseases that causes a heavy burden on public health. Given that bone marrow-derived mesenchymal stem cells (BMSCs) are of immense importance in osteoporosis development, it is necessary to expound the mechanisms underlying BMSC osteoblastic differentiation. Although mounting research works have investigated the role of small nucleolar RNA host gene 5 (SNHG5) in various diseases, elucidations on its function in osteoporosis are still scarce. It was observed that SNHG5 and RUNX family transcription factor 3 (RUNX3) were remarkably elevated during osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs). Further, we disclosed that the silencing of SNHG5 suppressed osteogenic differentiation and induced apoptosis of hBMSCs. What's more, SNHG5 acted as a competing endogenous RNA to affect RUNX3 expression via competitively binding with microRNA (miR)-582-5p. RUNX3 was also confirmed to simulate the transcriptional activation of SNHG5. Finally, our findings manifested that the positive feedback loop of SNHG5/miR-582-5p/RUNX3 executed the promoting role in the development of osteoporosis, which shed light on specific molecular mechanism governing SNHG5 in osteogenic differentiation and apoptosis of hBMSCs and indicated that SNHG5 may represent a novel target for the improvement of osteoporosis therapy.

The functional role of long noncoding RNA in resistance to anticancer treatment

Chemotherapy is one of the fundamental methods of cancer treatment. However, drug resistance remains the main cause of clinical treatment failure. We comprehensively review the newly identified roles of long noncoding RNAs (lncRNAs) in oncobiology that are associated with drug resistance. The expression of lncRNAs is tissue-specific and often dysregulated in human cancers. Accumulating evidence suggests that lncRNAs are involved in chemoresistance of cancer cells. The main lncRNA-driven mechanisms of chemoresistance include regulation of drug efflux, DNA damage repair, cell cycle, apoptosis, epithelial-mesenchymal transition (EMT), induction of signaling pathways, and angiogenesis. LncRNA-driven mechanisms of resistance to various antineoplastic agents have been studied extensively. There are unique mechanisms of resistance against different types of drugs, and each mechanism may have more than one contributing factor. We summarize the emerging strategies that can be used to overcome the technical challenges in studying and addressing lncRNA-mediated drug resistance.

LncRNA SNHG5: A new budding star in human cancers

Long non-coding RNA (LncRNA) belongs to non-coding RNAs longer than 200 nucleic acids. More and more studies have revealed that lncRNA can participate in the occurrence and pathophysiology of diseases, especially in cancers. Although research on lncRNAs has doubled year by year, little is known about the specific regulatory mechanisms of lncRNAs in diseases. The main purpose of this review is to explore the molecular mechanism and clinical significance of SNHG5 in cancers. We systematically search Pubmed to obtain relevant literature on SNHG5. In this review, the functional role, molecular mechanism, and clinical significance of SNHG5 in human cancers are described in detail. Small nucleolar RNA host gene 5 (SNHG5) has been shown to be involved in the development and tumorigenesis of a variety of cancers (colorectal, bladder, gastric, endometrial, acute lymphocytic leukemia, osteosarcoma, etc.). Its disorder is closely related to metastasis, pathological staging, and prognosis. LncRNA SNHG5 might be a potential and novel diagnostic marker for cancer patients, a target for molecular targeted therapy, and a prognostic diagnostic marker.

LncRNA SNHG5 regulates SOX4 expression through competitive binding to miR-489-3p in acute myeloid leukemia

OBJECTIVES

Currently, lncRNA plays an important role in the occurrence and development of acute myeloid leukemia (AML), including SNHG5. However, the role and mechanism of SNHG5 in AML remains unclear. In this study, we explored the regulatory mechanism of SNHG5 in the development of AML.

METHODS AND RESULTS

QRT-PCR was used to investigate the expression of SNHG5, miR-489-3p, and SOX. The proliferation and apoptosis of AML cells were analyzed by cell transfection, cell counting kit-8 (CCK8), and flow cytometric analysis. Moreover, the expression analysis of marker proteins was detected by western blot. Through luciferase activity assay, RNA pull-down, and RNA-binding protein immunoprecipitation (RIP), we proved that SNHG5 could bind miR-489-3p and SOX4 which might be the target gene of miR-489-3p.

RESULTS

We first found that SNHG5 was up-regulated in both AML patient bone marrow samples and various AML cell lines. Second, we found that knockdown of SNHG5 inhibited proliferation of AML cells and promoted apoptosis. It was found that SNHG5 could bind miR-489-3p, and the relative expression of SNHG5 was negatively correlated with miR-489-3p. Further results suggested that SOX4 might be the target gene of miR-489-3p. Finally, our experimental data indicated that knockdown of SNHG5 could reduce the tumor volume and down-regulated SOX4 levels in vivo.

CONCLUSIONS

Our results demonstrated that SNHG5 affected the expression of SOX4 through binding miR-489-3p to regulate proliferation and apoptosis of AML, which might act as a prospective prognostic biological marker and a promising therapeutic target for AML.

Non-coding RNAs in Lung Cancer Chemoresistance

Background:

Lung cancer is the leading cause of cancer-associated death worldwide with limited treatment options. The major available treatment options are surgery, radiotherapy, chemotherapy and combinations of these treatments. In chemotherapy, tyrosine kinase inhibitors and taxol are the first lines of chemotherapeutics used for the treatment of lung cancer. Often drug resistance in the clinical settings hinders the efficiency of the treatment and intrigues the tumor relapse. Drug-resistance is triggered either by intrinsic factors or due to the prolonged cycles of chemotherapy as an acquired-resistance. There is an emerging role of non-coding RNAs (ncRNAs), including notorious microRNAs (miRNAs), proposed to be actively involved in the regulations of various tumor-suppressor genes and oncogenes.

Result:

The altered gene expression by miRNA is largely mediated either by the degradation or by interfering with the translation of targeted mRNA. Unlike miRNA, other type of ncRNAs, such as long non-coding RNAs (lncRNAs), can target the transcriptional activator or the repressor, RNA polymerase, and even DNA-duplex to regulate the gene expressions. Many studies have confirmed the crucial role of ncRNAs in lung adenocarcinoma progression and importantly, in the acquisition of chemoresistance. Recently, ncRNAs have become early biomarkers and therapeutic targets for lung cancer.

Conclusion:

Targeting ncRNAs could be an effective approach for the development of novel therapeutics against lung cancer and to overcome the chemoresistance.

Long non-coding RNA SNHG5 regulates chemotherapy resistance through the miR-32/DNAJB9 axis in acute myeloid leukemia

BACKGROUND

Acute myeloid leukemia (AML) is a common hematopoietic malignancy with invasive activity. Drug resistance greatly contributes to the poor efficacy of chemotherapy in AML treatment. Recent research indicates that long non-coding RNAs (LncRNAs) regulates chemotherapy resistance in malignancy.

METHODS

Microarray analysis was used to screen out AML related genes, and interaction between small nucleolar RNA host gene 5(SNHG5) and miR-32, as well as that between miR-32 and DNAJB9. Quantitative real-time PCR (qRT-PCR) and In situ hybridization(ISH) were used to determine the expression levels of SNHG5, miR-32 and DNAJB9 mRNA in AML cell lines and clinic samples. Western blot was performed to detect protein expression levels. After being treated with varying concentrations of Adriamycin(ADM), cell viability was evaluated using a cell counting kit-8(CCK8).

RESULTS

We carried out a genome-wide LncRNA expression study and found SNHG5 aberrantly overexpressed in AML comparing to the donors. Knock-down of SNHG5 promoted sensitivity of AML cells to chemotherapy. In addition, miR-32 was identified as the downstream target of SNHG5 and miR-32 inhibitor abrogated the inhibiting effects of downregulated SNHG5 on AML cell viability. Furthermore, inhibited SNHG5 decreased DNAJB9 expression levels by sponging miR-32. The SNHG5/miR-32/DNAJB9 axis targeted autophagy to regulate chemotherapy resistance.

CONCLUSION

SHNG5 regulates chemotherapy resistance by targeting the miR-32/DNAJB9 axis in acute myeloid leukemia, which provided a novel potential target for AML and revealed an important mechanism of chemotherapy resistance.

SNHG14 confers gefitinib resistance in non-small cell lung cancer by up-regulating ABCB1 via sponging miR-206-3p

Gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), has been widely used as a first-line agent in EGFR-mutant non-small cell lung cancer (NSCLC). Nevertheless, the development of chemoresistance ultimately limited the curative effect of anti-cancer drugs. The present study aims to investigate the functions of SNHG14 in gefitinib resistance and gain insight into the underlying molecular mechanisms. In the present study, we found that SNHG14 expression was elevated and miR-206-3p expression was decreased in gefitinib-resistant NSCLC tumor tissues and cells. Functionally, SNHG14 overexpression increased gefitinib resistance by promoting cell viability, lowering apoptosis and enhancing colony forming ability, while SNHG14 knockdown reduced gefitinib resistance in NSCLC cells. Mechanistically, SNHG14 induced ABCB1 expression via interaction with miR-206-3p. Moreover, depletion of SNHG14 enhanced the sensitivity of NSCLC cells to gefitinib in vivo. Together, SNHG14 confers gefitinib resistance in NSCLC by regulating miR-206-3p/ABCB1 pathway, contributing to a better understanding of SNHG14 in acquired resistance and elucidating a candidate target to improve treatment response of NSCLC patients.

LncRNA SNHG5 promotes the progression of osteosarcoma by sponging the miR-212-3p/SGK3 axis

Background

Long non-coding RNA (lncRNA) SNHG5 has been found to play an important role in tumors. Nevertheless, the function and mechanism of lncRNA SNHG5 in osteosarcoma (OS) remains unclear. The purpose of this study was to investigate whether lncRNA SNHG5 can regulate the occurrence and development of OS cells.

Methods

We performed quantitative real time PCR to detect the expression of lncRNA SNHG5 in OS cells. 143B, MG63 (knockdown) and U2OS, U2R (overexpression) cell lines were chosen for the function study of SNHG5. The effect of SNHG5, miR-212-3p, and SGK3 in OS cells was explored by MTT assays, clony formation, flow cytometry, transwell assays, wound healing assays, and cell spreading assays. Quantitative real-time PCR, Western blot analysis and luciferase assays were used to detect the interaction between lncRNA SNHG5 and miR-212-3p.

Results

In this study, knockdown of lncRNA SNHG5 suppressed the growth and metastasis of OS cells, whereas the overexpression of SNHG5 produced an opposite result. Mechanistically, lncRNA SNHG5 functions as a sponger against miR-212-3p and suppresses the miR-212-3p/SGK3 signaling pathway. Introduction of miR-212-3p mimics or inhibitors reverses SNHG5 overexpression or silences the exerted tumor promoting or suppressing effect. In addition, our results showed that the function of SNHG5 can be rescued by miR-212-3p and can regulate the growth and metastasis of OS cells via SGK3, the downstream target of miR-212-3p.

Conclusions

In summary, our study demonstrated that lncRNA SNHG5 can regulate the proliferation and metastasis of OS cells through the miR-212-3p/SGK3 axis. This axis may provide a new target for future clinical treatment.

Electronic supplementary material

The online version of this article (10.1186/s12935-018-0641-9) contains supplementary material, which is available to authorized users.

Effect of lncRNA ANRIL silencing on anoikis and cell cycle in human glioma via microRNA-203a

BACKGROUND

Glioma is a deadly nervous system tumor with a poor prognosis. Although there have been many efforts to overcome glioma, the molecular mechanism of its pathogenesis remains unclear.

METHODS

We used human glioma U251 cells silenced for the oncogenic lncRNA ANRIL or overexpressing the anti-oncogene miR-203a to examine the role of lncRNA ANRIL silencing on anoikis and cell cycle arrest by flow cytometry. Meanwhile, the activity of caspase-3/8/9 was measured by fluorometric assay, the expression of tumor-related genes and activity of AKT signaling pathway was measured by Western blotting, real-time PCR, and dual luciferase reporter gene assay.

RESULTS

lncRNA ANRIL was positively correlated with glioma grade and negatively correlated with miR-203a. lncRNA ANRIL silencing could induce anoikis and cell cycle arrest in G0/G1 phase, while regulating the activity of caspase-3/8/9 and the AKT signaling pathway, and the expression of tumor-related genes in the U251 cell line. miR-203a mimics could partially reverse these functions.

CONCLUSION

We consider that lncRNA ANRIL is a potential therapeutic and diagnostic target for glioma, and miR-203a plays an important role in the biological function of lncRNA ANRIL in glioma.

A circRNA-miRNA-mRNA network identification for exploring underlying pathogenesis and therapy strategy of hepatocellular carcinoma

BACKGROUND

Circular RNAs (circRNAs) have received increasing attention in human tumor research. However, there are still a large number of unknown circRNAs that need to be deciphered. The aim of this study is to unearth novel circRNAs as well as their action mechanisms in hepatocellular carcinoma (HCC).

METHODS

A combinative strategy of big data mining, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and computational biology was employed to dig HCC-related circRNAs and to explore their potential action mechanisms. A connectivity map (CMap) analysis was conducted to identify potential therapeutic agents for HCC.

RESULTS

Six differently expressed circRNAs were obtained from three Gene Expression Omnibus microarray datasets (GSE78520, GSE94508 and GSE97332) using the RobustRankAggreg method. Following the RT-qPCR corroboration, three circRNAs (hsa_circRNA_102166, hsa_circRNA_100291 and hsa_circRNA_104515) were selected for further analysis. miRNA response elements of the three circRNAs were predicted. Five circRNA-miRNA interactions including two circRNAs (hsa_circRNA_104515 and hsa_circRNA_100291) and five miRNAs (hsa-miR-1303, hsa-miR-142-5p, hsa-miR-877-5p, hsa-miR-583 and hsa-miR-1276) were identified. Then, 1424 target genes of the above five miRNAs and 3278 differently expressed genes (DEGs) on HCC were collected. By intersecting the miRNA target genes and the DEGs, we acquired 172 overlapped genes. A protein-protein interaction network based on the 172 genes was established, with seven hubgenes (JUN, MYCN, AR, ESR1, FOXO1, IGF1 and CD34) determined from the network. The Gene Oncology, Kyoto Encyclopedia of Genes and Genomes and Reactome enrichment analyses revealed that the seven hubgenes were linked with some cancer-related biological functions and pathways. Additionally, three bioactive chemicals (decitabine, BW-B70C and gefitinib) based on the seven hubgenes were identified as therapeutic options for HCC by the CMap analysis.

CONCLUSIONS

Our study provides a novel insight into the pathogenesis and therapy of HCC from the circRNA-miRNA-mRNA network view.