SNHG6 is upregulated in primary breast cancers and promotes cell cycle progression in breast cancer-derived cell lines

New insights of LncRNAs fingerprints in breast cancer progression: Tumorigenesis, drug resistance, and therapeutic opportunities

Breast cancer (BC) is one of the common female cancers and it is characterized by considerable problems regarding its development and therapy. Long non-coding RNAs (lncRNAs) have been identified as significant modulators in BC development, especially, in tumorigenicity and chemoresistance. We therefore endeavor to present an up-to-date understanding of lncRNAs and their impact on BC progression and treatment, concerning molecular processes, treatment options, and use as a therapeutic opportunity. LncRNAs are novel regulators of genes that cause therapeutic resistance and directly impact the functioning of both coding and non-coding genes in BC patients, but little is known about their mechanisms of actions. Thus, additional study is required to have a deeper understanding of their modes of action and possible roles in BC disease. This study aims to investigate the functions of lncRNAs in the development of BC, with particular attention to their role in tumorigenesis, drug resistance mechanisms, and therapeutic targets. This will help to identify novel therapeutic targets and improve the effectiveness of BC treatment.

Immunosuppressive SOX9-AS1 Resists Triple-Negative Breast Cancer Senescence Via Regulating Wnt Signalling Pathway

Long noncoding RNAs (lncRNAs) are involved in the regulation of triple-negative breast cancer (TNBC) senescence, while pro-carcinogenic lncRNAs resist senescence onset leading to the failure of therapy-induced senescence (TIS) strategy, urgently identifying the key senescence-related lncRNAs (SRlncRNAs). We mined seven SRlncRNAs (SOX9-AS1, LINC01152, AC005152.3, RP11-161 M6.2, RP5-968 J1.1, RP11-351 J23.1 and RP11-666A20.3) by bioinformatics, of which SOX9-AS1 was reported to be pro-carcinogenic. In vitro experiments revealed the highest expression of SOX9-AS1 in MDA-MD-231 cells. SOX9-AS1 knockdown inhibited cell growth (proliferation, cycle and apoptosis) and malignant phenotypes (migration and invasion), while SOX9-AS1 overexpression rescued these effects. Additionally, SOX9-AS1 knockdown facilitated tamoxifen-induced cellular senescence and the transcription of senescence-associated secretory phenotype (SASP) factors (IL-1α, IL-1β, IL-6 and IL-8) mechanistically by resisting senescence-induced Wnt signal (GSK-3β/β-catenin) activation. Immune infiltration analysis revealed that low SOX9-AS1 expression was accompanied by a high infiltration of naïve B cells, CD8+ T cells and γδ T cells. In conclusion, SOX9-AS1 resists TNBC senescence via regulating the Wnt signalling pathway and inhibits immune infiltration. Targeted inhibition of SOX9-AS1 enhances SASP and thus mobilises immune infiltration to adjunct TIS strategy.

Therapeutic significance of long noncoding RNAs in estrogen receptor-positive breast cancer

About 70% of cases of breast cancer are compromised by Estrogen-positive breast cancer. Through its regulation of several processes, including cell proliferation, cell cycle progression, and apoptosis, Estrogen signaling plays a pivotal role in the genesis and progression of this particular kind of breast cancer. One of the best treatment strategies for treating Estrogen-positive breast cancer is blocking Estrogen signaling. However, patients' treatment failure is mainly caused by the emergence of resistance and metastases, necessitating the development of novel therapeutic targets. Numerous studies have shown long noncoding RNAs (lncRNAs) to play a role in Estrogen-mediated carcinogenesis. These lncRNAs interact with co-regulators and the Estrogen signaling cascade components, primarily due to Estrogen activation. Vimentin and E-cadherin are examples of epithelial-to-mesenchymal transition markers, and they regulate genes involved in cell cycle progression, such as Cyclins, to affect the growth, proliferation, and metastasis of Estrogen-positive breast cancer. Furthermore, a few of these lncRNAs contribute to developing resistance to chemotherapy, making them more desirable targets for enhancing results. Thus, to shed light on the creation of fresh approaches for treating this cancer, this review attempts to compile recently conducted studies on the relationship between lncRNAs and the advancement of Estrogen-positive breast cancer.

Discovering biomarkers associated and predicting cardiovascular disease with high accuracy using a novel nexus of machine learning techniques for precision medicine

Personalized interventions are deemed vital given the intricate characteristics, advancement, inherent genetic composition, and diversity of cardiovascular diseases (CVDs). The appropriate utilization of artificial intelligence (AI) and machine learning (ML) methodologies can yield novel understandings of CVDs, enabling improved personalized treatments through predictive analysis and deep phenotyping. In this study, we proposed and employed a novel approach combining traditional statistics and a nexus of cutting-edge AI/ML techniques to identify significant biomarkers for our predictive engine by analyzing the complete transcriptome of CVD patients. After robust gene expression data pre-processing, we utilized three statistical tests (Pearson correlation, Chi-square test, and ANOVA) to assess the differences in transcriptomic expression and clinical characteristics between healthy individuals and CVD patients. Next, the recursive feature elimination classifier assigned rankings to transcriptomic features based on their relation to the case-control variable. The top ten percent of commonly observed significant biomarkers were evaluated using four unique ML classifiers (Random Forest, Support Vector Machine, Xtreme Gradient Boosting Decision Trees, and k-Nearest Neighbors). After optimizing hyperparameters, the ensembled models, which were implemented using a soft voting classifier, accurately differentiated between patients and healthy individuals. We have uncovered 18 transcriptomic biomarkers that are highly significant in the CVD population that were used to predict disease with up to 96% accuracy. Additionally, we cross-validated our results with clinical records collected from patients in our cohort. The identified biomarkers served as potential indicators for early detection of CVDs. With its successful implementation, our newly developed predictive engine provides a valuable framework for identifying patients with CVDs based on their biomarker profiles.

Role of long non-coding RNAs and TGF-β signaling in the regulation of breast cancer pathogenesis and therapeutic targets

The cytokine known as transforming growth factor (TGF) is essential for cell development, differentiation, and apoptosis in BC. TGF-β dysregulation can either promote or inhibit tumor development, and it is a key signaling pathway in BC spread. A recently identified family of ncRNAs known as lncRNAs has received a great deal of effort and is an important regulator of many cellular processes, including transcription of genes, chromatin remodeling, progression of the cell cycle, and posttranscriptional processing. Furthermore, both TGF-β signaling and lncRNAs serve as important early-stage biomarkers for BC diagnosis and prognosis and also play a significant role in BC drug resistance. According to recent studies, lncRNAs can regulate TGF-β by modulating its cofactors in BC. However, the particular functions of lncRNAs and the TGF-β pathway in controlling BC progression are not well understood yet. This review explores the lncRNAs' functional properties in BC as tumor suppressors or oncogenes in the regulation of genes, with a focus on dysregulated TGF-β signaling. Further, we emphasize the functional roles of lncRNAs and TGF-β pathway in the progression of BC to discover new treatment strategies and better comprehend the fundamental cellular pathways.

LncRNA SNHG6 role in clinicopathological parameters in cancers

RNA sequencing has revealed that a substantial portion of the human genome undergoes transcription, yet a minimal fraction of these transcripts translates into proteins. LncRNAs, RNA molecules less than 200 nt in length, once deemed as transcriptional noise, have now emerged as crucial regulators of numerous cellular processes. This review focuses on the lncRNA SNHG6, aiming to elucidate its biogenesis, the pivotal roles it plays, and its mechanisms in facilitating the hallmarks of cancer. A comprehensive literature review and analysis were undertaken to delve into the biogenesis of SNHG6, its roles in cellular processes, and the mechanisms through which it contributes to the hallmarks of cancer. SNHG6 is a notable lncRNA, observed to be overexpressed in various cancer types; its perturbation has been linked to tumor progression, emphasizing its significance in oncogenesis. This lncRNA contributes to a range of cellular aberrations, influencing transcriptional, post-transcriptional, and epigenetic processes of mRNA, ultimately driving cancerous transformations. LncRNA SNHG6 serves as a potential biomarker and therapeutic target due to its association with tumorigenesis. Understanding its mechanism and role in cancer can pave the way for novel diagnostic and therapeutic strategies.

Revisiting the hallmarks of cancer: A new look at long noncoding RNAs in breast cancer

Breast cancer is one of the leading causes of death in women worldwide. The increasing understanding of the molecular mechanisms underlying its heterogeneity favors a better understanding of tumor biology and consequently the development of better diagnostic and treatment techniques. The advent of tumor genome sequencing techniques has highlighted more participants in the process, in addition to protein-coding genes. Thus, it is now known that long noncoding RNAs, previously described as transcriptional noise with no biological function, are intimately associated with tumor development. In breast cancer, they are abnormally expressed and closely associated with tumor progression, which makes them attractive diagnostic biomarkers and prognostic and specific therapeutic targets. Therefore, a thorough understanding of the regulatory mechanisms of long noncoding RNAs in breast cancer is essential for the search for new treatment strategies. In this review, we summarize the major long noncoding RNAs and their association with the cancer characteristics of the ability to sustain proliferative signaling, evasion of growth suppressors, replicative immortality, activation of invasion and metastasis, induction of angiogenesis, resistance to cell death, reprogramming of energy metabolism, genomic instability and sustained mutations, promotion of tumor inflammation, and evasion of the immune system. In addition, we report and suggest how they can be used as prognostic biomarkers and possible therapeutic targets.

The LncRNA MIAT is identified as a regulator of stemness-associated transcript in glioma

BACKGROUND

Myocardial infarction-associated transcript (MIAT) is a long non-coding RNA (lncRNA) with altered expression in different diseases and malignancies. In this study, the potential expression and function of lncRNA MIAT in intuition and progression of brain cancer was investigated.

METHODS AND RESULTS

At first, TCGA data analysis demonstrated that lncRNA MIAT is significantly upregulated in various malignancies, especially its expression is dramatically elevated in brain tumors. In line with the data, we further evaluated the expression of MIAT in a series of brain tumor tissue, and our results revealed that the expression of MIAT was noticeably overexpressed in glioblastoma (p = < 0.0001). We further found that the expression of MIAT was markedly upregulated in low-grade brain tumors rather than high-grade ones. To further investigate the biological function of MIAT in brain cancer cells, its expression was suppressed by si-RNA-mediated knocking down. Inhibition of MIAT resulted in reduced proliferation of brain tumor cells followed by cell cycle arrest at the G1 phase, and significant induction of apoptosis, and senescence, but limited the migration ability and epithelial-mesenchymal-transition (EMT). Moreover, knocking-down of MIAT reduced the expression of stemness factors, followed by upregulation of their downstream miRNAs (micro RNAs), let-7a-5p, and miR-29b-3p.

CONCLUSIONS

Altogether, our data demonstrated that lncRNA MIAT could control proliferation, migration, and metastasis of brain cancer cells via regulating the Nanog/ Sox2 / let-7a-5p / miR-29b-3p axis. This data could introduce lncRNA MIAT as a novel oncogene in brain cancer pathogenesis.

Gene amplification-driven lncRNA SNHG6 promotes tumorigenesis via epigenetically suppressing p27 expression and regulating cell cycle in non-small cell lung cancer

Long non-coding RNAs (lncRNAs) have been validated to play essential roles in non-small cell lung carcinoma (NSCLC) progression. In this study, through systematically screening GSE33532 and GSE29249 from Gene Expression Omnibus (GEO) database and bioinformatics analysis, we found the significant upregulation of SNHG6 in NSCLC. The activation of SNHG6 was driven by copy number amplification and high expression of SNHG6 indicated a poor prognosis. Functionally, the knockdown of SNHG6 inhibited NSCLC cell proliferation, migration, and suppressed the G1/S transition of the cell cycle. SNHG6 overexpression had the opposite effects. Mechanically, SNHG6 recruited EZH2 to the promoter region of p27 and increased H3K27me3 enrichment, thus epigenetically repressing the expression of p27, regulating the cell cycle, and promoting tumorigenesis of NSCLC. SNHG6 silencing restrained tumor growth in vivo and suppressed the expressions of cell cycle-related proteins in the G1/S transition. In conclusion, our study uncovered a novel mechanism of SNHG6 activation and its function. SNHG6 can be considered a potential target for the diagnosis and treatment of NSCLC in the future.

LncRNA SNHG6 promotes glycolysis reprogramming in hepatocellular carcinoma by stabilizing the BOP1 protein

Metabolic reprogramming is an important feature in tumor progression. Long noncoding RNA's (lncRNA) small nucleolar RNA host gene 6 (SNHG6) acts as a proto-oncogene in hepatocellular carcinoma (HCC) but its role in glycolysis is mostly unknown. The role of SNHG6 and Block of proliferation 1 (BOP1) on glycolysis is assessed by glucose uptake, lactate production, oxygen consumptive rate (OCR) and extracellular acidification rate (ECAR) and glycolytic enzyme levels. The regulatory effect of SNHG6 on BOP1 protein was confirmed by Western blotting, MS2 pull-down, RNA pull-down, and RIP assay. SNHG6 and BOP1 levels were increased in HCC tissues and cells. SNHG6 and BOP1 were prognostic factors in HCC patients and significantly correlated to TP53 mutant and tumor grade. SNHG6 promoted proliferation, inhibited apoptosis, enhanced glucose uptake and lactate production, decreased OCR, and increased ECAR in HCC cell lines. SNHG6 could bind the BOP1 protein and enhance its stability. BOP1 overexpression rescued the change of proliferation, apoptosis, and glycolysis in HCCLM3 and SMMC-7721 cells. Our data indicate that SNHG6 accelerates proliferation and glycolysis and inhibits the apoptosis of HCC cell lines by binding the BOP1 protein and enhancing its stability. Both SNHG6 and BOP1 are promising prognostic and therapeutic markers in HCC.

lncRNA ACTA2-AS1 inhibits malignant phenotypes of gastric cancer cells

Gastric cancer (GC) is one of the most common malignancies in digestive system. Accumulating evidence reveals the critical role of long noncoding RNAs (lncRNAs) in GC development. The study aimed to explore the functions and mechanism of lncRNA actin alpha 2, smooth muscle antisense RNA 1 (ACTA2-AS1) in GC. Reverse transcription-quantitative polymerase chain reaction analyses and subcellular fractionation assays showed that ACTA2-AS1 was lowly expressed in GC cells and was mainly distributed in the cytoplasm. Overexpressed ACTA2-AS1 inhibited GC cell viability, proliferation, migration, invasion, and epithelial-mesenchymal transition process, as suggested by cell counting kit-8 assays, colony formation assays, wound healing assays, Transwell assays and Western blot analyses. Mechanistically, ACTA2-AS1 served as a competing endogenous RNA (ceRNA) to bind with miR-378a-3p and thereby, antagonized the inhibitory effect of miR-378a-3p on the expression of messenger RNA phosphatidylinositol specific phospholipase C X domain containing 2 (PLCXD2). The binding capacity between miR-378a-3p and ACTA2-AS1 (or PLCXD2) was detected by RNA pulldown assays, luciferase reporter assays and RNA immunoprecipitation assays. Moreover, PLCXD2 knockdown rescued the inhibitory effect of ACTA2-AS1 overexpression on malignant behaviors of GC cells. Overall, ACTA2-AS1 inhibits malignant phenotypes of GC cells by acting as a ceRNA to target miR-378a-3p/PLCXD2 axis.

LncRNA SNHG6 facilitates cell proliferation, migration, invasion and EMT by upregulating UCK2 and activating the Wnt/β-catenin signaling in cervical cancer

Cervical cancer is a most prevalent gynecological malignancy around the world. Long non-coding RNAs (lncRNAs) are recognized as crucial players in the cellular activities of diverse cancers including cervical cancer. We aimed to reveal the biological function of lncRNA small nucleolar RNA host gene 6 (SNHG6) in cervical cancer. Our findings illuminated that SNHG6 expression was elevated in cervical cancer tissues and cell lines, and highly expressed SNHG6 was associated with poor outcome in patients with cervical cancer. Moreover, knockdown of SNHG6 repressed cervical cancer development via inhibiting cell proliferation and migration and accelerating cell apoptosis. Further, SNHG6 was a sponge of miR-485-3p and uridine-cytidine kinase 2 (UCK2) was the functional target of miR-485-3p. SNHG6 increased UCK2 expression by binding with miR-485-3p in cervical cancer cells. The rescue experiments showed that SNHG6 contributed to malignant phenotypes of cervical cancer cells by the miR-485-3p/UCK2 axis. Additionally, SNHG6 activated the Wnt/β-catenin pathway to enhance the proliferative and migratory ability of cervical cancer cells. Overall, this work revealed that SNHG6 promoted malignant behaviors of cervical cancer cells by binding with miR-485-3p to regulate UCK2 and activating the Wnt/β-catenin pathway, which may offer a beneficial direction to treat cervical cancer.

A novel immune-related ceRNA network that predicts prognosis and immunotherapy response in lung adenocarcinoma

Background

The tumor microenvironment plays an important role in the progression and malignancy of lung adenocarcinoma and affects the immunotherapy response. There is increasing evidence that long non-coding RNAs (lncRNAs) as competing endogenous RNAs (ceRNAs) have significant functions in the development and treatment response of various kinds of cancer. This study aimed to explore the association between immune-related lncRNA-microRNA (miRNA)-messenger RNA (mRNA)-ceRNA networks, and the prognosis of and immunotherapy response in lung adenocarcinoma.

Methods

RNA-sequencing (RNA-seq) and miRNA-seq data from The Cancer Genome Atlas (TCGA) were used to evaluate the infiltration of immune cells in lung adenocarcinoma samples by undertaking a single-sample gene set enrichment analysis (ssGSEA) to divide the cells into high and low immune cell infiltration groups. The differentially expressed mRNA (DEmRNA) was further analyzed by a weighted gene co-expression network analysis (WGCNA), search tool for recurring instances of neighboring genes (STRING), and Cytoscape to select hub genes. The ceRNA network was constructed using Cytoscape. Additionally, survival analyses were conducted to screen out prognostic candidate genes.

Results

Seven thousand five hundred and thirty-eight mRNAs, 540 lncRNAs, and 138 miRNAs were found to be differentially expressed between the high and low immune cell infiltration groups. The two DEmRNA modules most significantly associated with immune cell infiltration were further analyzed, and four clusters, including 179 DEmRNAs, were selected based on Molecular Complex Detection (MCODE) scores. The selected DEmRNAs in the four clusters were mainly enriched in pathways involved in regulating the immune response. Ultimately, a ceRNA network of SNHG6-hsa-miR-30e-5p-CYSLTR1 was identified as being associated with the prognosis of and immunotherapy response in lung adenocarcinoma.

Conclusions

The present study extends understandings of immune-related lncRNA-miRNA-mRNA-ceRNA networks and identifies novel targets and a regulatory pathway for anti-tumor immunotherapy.

Tumor Targeting by Conditioned Medium Derived From Human Amniotic Membrane: New Insight in Breast Cancer Therapy

Objectives:

Traditional breast cancer treatments have challenges including inefficiency, multidrug resistance, severe side effects, and targeting non-specifically. The development of alternative treatment strategies has attracted a great deal of interest. Using the amniotic membrane has become a promising and convenient new approach for cancer therapy. This study aimed to evaluate the anti-cancer ability of conditioned medium extracted from the human amniotic membrane (hAM-CM) on breast cancer cells.

Methods:

Conditioned medium was collected after 48 h incubation of hAM in epithelial up manner. MTT, cell cycle, apoptosis, colony formation, and sphere assays were used to determine the impact of hAM-CM on breast cancer cell lines. The effects of hAM-CM on the migration and invasion of breast cancer cells were determined using scratch wound healing and transwell assays, respectively.

Results:

Based on the results, cell viability was significantly decreased by hAM-CM in a dose-dependent manner. The hAM-CM remarkably induced apoptosis and necrosis of cancer cells. Moreover, cell migration and invasion potential of cancer cells decreased after the hAM-CM treatment. Further, both the number of colonies and their morphologies were affected by the treatment. In the treated group, a significant decrease in the number of colonies along with an obvious change in their morphologies from holoclone shape to a dominant paracolone structure was observed.

Conclusion:

Our results indicate that the conditioned medium derived from the human amniotic membrane able to inhibit proliferation and metastasis of tumor cells and can be considered a natural and valuable candidate for breast cancer therapy.

Long non-coding RNA TPT1-AS1 sensitizes breast cancer cell to paclitaxel and inhibits cell proliferation by miR-3156-5p/caspase 2 axis

Long non-coding RNAs (lncRNAs) are key modulators during cancer progression. Application of using lncRNA expression to evaluate patient prognosis and sensitivity to treatment is highly anticipated, yet the expression and mechanism of many lncRNAs remain unknown. Herein, we projected for the investigation of TPT1-AS1 function in breast cancer. TPT1-AS1 was assessed by bioinformatic analysis of publicly available datasets and quantitative real-time PCR (qRT-PCR). Cell sensitivity to paclitaxel and cell proliferation was measured by flow cytometry and CCK-8. Interaction among TPT1-AS1, microRNA (miRNA, miR)-3156-5p and Caspase 2 (CASP2) was studied by bioinformatic analysis, qRT-PCR, western blot as well as dual luciferase reporter assay. Herein, TPT1-AS1 was significantly diminished in breast cancer from publicly available datasets and our collected samples. In breast cancer cells, TPT1-AS1 overexpression repressed cell proliferation and sensitized breast cancer cells to paclitaxel. RegRNA 2.0 predicted a potential interaction between TPT1-AS1 and miR-3156-5p which was confirmed by qRT-PCR as well as dual luciferase reporter assay. CASP2, a proapoptotic gene, was corroborated to be targeted by miR-3156-5p. Meanwhile, TPT1-AS1 upregulated CASP2 in breast cancer cells, and its biological function was reversed by CASP2 knockdown. Collectively, TPT1-AS1 diminished cell proliferation and sensitized cells to chemotherapy by sponging miR-3156-5p and upregulating CASP2, acting as a biomarker for patients with breast cancer.

Small nucleolar RNA host genes promoting epithelial-mesenchymal transition lead cancer progression and metastasis

The small nucleolar RNA host genes (SNHGs) belong to the long non-coding RNAs and are reported to be able to influence all three levels of cellular information-bearing molecules, that is, DNA, RNA, and proteins, resulting in the generation of complex phenomena. As the host genes of the small nucleolar RNAs (snoRNAs), they are commonly localized in the nucleolus, where they exert multiple regulatory functions orchestrating cellular homeostasis and differentiation as well as metastasis and chemoresistance. Indeed, worldwide literature has reported their involvement in the epithelial-mesenchymal transition (EMT) of different histotypes of cancer, being able to exploit peculiar features, for example, the possibility to act both in the nucleus and the cytoplasm. Moreover, SNHGs regulation is a fundamental topic to better understand their role in tumor progression albeit such mechanism is still debated. Here, we reviewed the biological functions of SNHGs in particular in the EMT process and discussed the perspectives for new cancer therapies.

LncRNA SNHG6/miR-125b-5p/BMPR1B Axis: A New Therapeutic Target for Triple-Negative Breast Cancer

Background

Triple-negative breast cancer (TNBC) is a significant cause of patient morbidity. The exactly pathobiological features of this condition has yet to be completely elucidated.

Methods

Breast cancer data obtained from The Cancer Genome Atlas (TCGA) database were evaluated for lncRNA SNHG6 expression. Normal human breast epithelial cell line (MCF-10A) and other breast cancer cell lines (BT-549, MDA-MB-231, Hs 578t, ZR-75-30, SK-BR-3, MCF-7) were also assessed for lncRNA SNHG6 expressions. Cellular proliferative ability was evaluated with colony formation and CCK-8 assays. The ability of cells to migrate was scrutinized with the wound healing and Boyden chamber cell migration assays. qRT-PCR enabled for detection of lncRNA SNHG6, miR-125b-5p and BMPR1B mRNA expressions. Protein BMPR1B expressions were further assessed using Western Blotting. Direct binding sites between transcripts were determined using dual-luciferase reporter assays. We also constructed a xenograft mouse model to further dissect the vivo implications of lncRNA SNHG6. Ki-67 and c-Caspase-3 expressions were detected using immunohistochemistry staining.

Results

Breast cancer cell lines demonstrated higher lncRNA SNHG6 expressions, particularly TNBC cell lines, in contrast to normal breast epithelial cell lines. This finding coincided with those noted on analysis of TCGA breast cancer data. lncRNA SNHG6 knockdown inhibited TNBC cell proliferation, migration, while promoted cell apoptosis. Furthermore, suppressed lncRNA SNHG6 expressions resulted in lower tumor weights and volumes in a xenograft mouse model, as evidenced by Ki-67 and c-Caspase-3 expression profiles in tumor tissues. miR-125b-5p and lncRNA SNHG6/BMPR1B both possessed direct binding sites for each other which was validated utilizing a dual-luciferase reporter assay. Decreasing lncRNA SNHG6 expression in TNBC cells upregulated miR-125b-5p expression. Another side, inhibiting miR-125b-5p upregulated BMPR1B expression in these cells. Moreover, knocking down lncRNA SNHG6 downregulated BMPR1B expression in TNBC cells, and the finding was rescued in cells which were exposed to miR-125b-5p inhibitor. Downregulating miR-125b-5p mitigated the effect of suppressing lncRNA SNHG6 on TNBC cell proliferation, migration, and apoptosis.

Conclusion

Downregulation of lncRNA SNHG6 could inhibit TNBC cell proliferative, migratory capabilities and promote apoptosis capability, likely through modulation of the miR-125b-5p/BMPR1B axis. This axis may be targeted in formulating new therapies for TNBC.

LncRNA SNHG6 promotes breast cancer progression and epithelial-mesenchymal transition via miR-543/LAMC1 axis

PURPOSE

Breast cancer (BC) is the most prevalent cancer in women with an estimated incidence of 10% and the leading cause of mortality due to its heterogenous property and high metastasis rate. Development of novel therapy is very necessary and requires an understanding of molecular mechanisms. We investigated the function of SNHG6/miR-543/LAMC1 axis in BC.

METHODS

Human BC tissues were obtained from diagnosed patients. BC cell lines and normal breast cells were used. QRT-PCR and Western blotting were employed to measure expression levels of SNHG6, miR-543, LAMC1, EMT-related proteins, and PI3K/AKT pathway. Dual-luciferase assay was performed to validate interactions of SNHG6/miR-543 and miR-543/LAMC1. Colony formation assay, flow cytometry, scratch wound healing assay, and transwell assay were utilized to assess the proliferation, apoptosis, migration, and invasion of BC cells. Nude mouse xenograft model was used the evaluate the function of SNHG6/miR-543 in tumor growth in vivo.

RESULTS

SNHG6 and LAMC1 were elevated, but miR-543 was reduced in BC tissues and cells. SNHG6 interacted directly with miR-543, while miR-543 targeted LAMC1. Knockdown of SNHG6 suppressed BC cell proliferation, migration, invasion, EMT, and PI3K/AKT pathway, but promoted cell apoptosis, while miR-543 inhibitor or overexpression of LAMC1 reversed those effects. Overexpression of LAMC1 also blocked the effects of miR-543 on BC cell proliferation, migration, invasion, and EMT. Knockdown of SNHG6 restrained BC growth in vivo, while miR-543 inhibitor inhibited that suppression.

CONCLUSION

SNHG6 promoted EMT and BC cell proliferation and migration by acting as a miR-543 sponge and disinhibiting LAMC1/PI3K/AKT pathway. SNHG6/miR-543/LAMC1 axis could serve as candidates for the development of therapeutic strategies for BC.

Small nucleolar RNA and its potential role in breast cancer - A comprehensive review

Small Nucleolar RNAs (snoRNAs) are known for their canonical functions, including ribosome biogenesis and RNA modification. snoRNAs act as endogenous sponges that regulate miRNA expression. Thus, precise snoRNA expression is critical for fine-tuning miRNA expression. snoRNAs processed into miRNA-like sequences play a crucial role in regulating the expression of protein-coding genes similar to that of miRNAs. Recent studies have linked snoRNA deregulation to breast cancer (BC). Inappropriate snoRNA expression contributes to BC pathology by facilitating breast cells to acquire cancer hallmarks. Since snoRNAs show significant differential expression in normal and cancer conditions, measuring snoRNA levels could be useful for BC prognosis and diagnosis. The present article provides a comprehensive overview of the role of snoRNAs in breast cancer pathology. More specifically, we have discussed the regulation, biological function, signaling pathways, and clinical utility of abnormally expressed snoRNAs in BC. Besides, we have also discussed the role of snoRNA host genes in breast tumorigenesis and emerging and future research directions in the field of snoRNA and cancer.

SNHG6 Interacted with miR-325-3p to Regulate Cisplatin Resistance of Gastric Cancer by Targeting GITR

Background

Cisplatin resistance results in the failure of platinum-based chemotherapy and relapse of gastric cancer. We aimed to investigate the potential regulating role of SNHG6/miR-325-3p/GITR in reversing cisplatin resistance.

Patients and Methods

A total of 137 gastric cancer patients were recruited. qRT-PCR and ELISA were used to test the expression of target genes. CCK-8 and caspase 3/7 kit were used to test the cell viability and apoptosis rate. Dual luciferase reporter gene and RNA-pull down assay were used to investigate the potential interaction between target genes.

Results

SNHG6 and GITR were up regulated in gastric cancer; however, miR-325-3p was down-regulated. Besides, SNHG6, miR-325-3p and GITR expression were associated with gastric cancer prognosis. Then, we found that GITR and SNHG6 promoted proliferation and inhibited apoptosis of MKN45 and MKN45 cisplatin resistance cell line; however, miR-325-3p inhibited proliferation and promoted apoptosis of these cell lines. Furthermore, SNHG6 might bind to miR-325-3p to regulate its expression, and miR-325-3p directly interacted with the 3`UTR of GITR.

Conclusion

SNHG6 binds to miR-325-3p, which directly interacted with GITR to regulate cisplatin resistance of gastric cancer.

The Role of Non-Coding RNAs in Controlling Cell Cycle Related Proteins in Cancer Cells

Cell cycle is regulated by a number of proteins namely cyclin-dependent kinases (CDKs) and their associated cyclins which bind with and activate CDKs in a phase specific manner. Additionally, several transcription factors (TFs) such as E2F and p53 and numerous signaling pathways regulate cell cycle progression. Recent studies have accentuated the role of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) in the regulation of cell cycle. Both lncRNAs and miRNAs interact with TFs participating in the regulation of cell cycle transition. Dysregulation of cell cycle regulatory miRNAs and lncRNAs results in human disorders particularly cancers. Understanding the role of lncRNAs, miRNAs, and TFs in the regulation of cell cycle would pave the way for design of anticancer therapies which intervene with the cell cycle progression. In the current review, we describe the role of lncRNAs and miRNAs in the regulation of cell cycle and their association with human malignancies.

LncRNA SNHG6 Inhibits Apoptosis by Regulating EZH2 Expression via the Sponging of MiR-101-3p in Esophageal Squamous-Cell Carcinoma

Background

The long non-coding RNA (lncRNA) SNHG6 was significantly upregulated in esophageal squamous-cell carcinoma (ESCC), and it promoted ESCC cell proliferation, invasion, and migration. However, the effects of SNHG6 on cell apoptosis and the corresponding underlying mechanisms have not yet reported.

Methods

Apoptosis was detected by flow cytometric analysis. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were used for mRNA and protein quantification, respectively. A luciferase reporter assay was performed to verify downstream target genes for SNHG6 and miR-101-3p.

Results

Dysregulation of SNHG6 inhibited apoptosis in ESCC cells and regulated the expression of apoptosis-related proteins such as Bcl-2, Mcl-1, Bax and Caspase-3. Functionally, miR-101-3p could compete binding with 3′-untranslated region of SNHG6 and downregulation of miR-101-3p reversed its effect on cell apoptosis in SNHG6 knockdown cells. EZH2 was confirmed as a downstream target gene of miR-101-3p, silencing EZH2 expression had the same effect on apoptosis and protein expression as knocking down SNHG6. Overexpression of EZH2 reversed the effects of miR-101-3p overexpression on cell apoptosis in ESCC cells.

Conclusion

In this study, we found that upregulation of the lncRNA SNHG6 inhibited apoptosis via miR-101-3p/EZH2 axis in ESCC. These findings may contribute to the diagnosis and treatment of ESCC.

Long non-coding RNA SNHG6 increases JAK2 expression by targeting the miR-181 family to promote colorectal cancer cell proliferation

BACKGROUND

Long non-coding RNA (lncRNA) small nucleolar RNA host gene 6 (SNHG6) exerts a regulatory role in cancer biology, although its detailed functions and mechanisms in colorectal cancer (CRC) still remain unclear.

METHODS

A quantitative reverse transcriptase-polymerase chain reaction was implemented to investigate the expression of SNHG6, miR-181 family and Janus kinase 2 (JAK2) in CRC tissues and cell lines. The proliferation of CRC cells was detected by a cell counting kit-8 assay, and the apoptosis of CRC cells was determined by flow cytometry analysis. The interaction of the miR-181 family with SNHG6 or with the 3'-untranslated region of JAK2 was validated by the luciferase reporter gene method. The effects of SNHG6 and the miR-181 family on JAK2 expression were analyzed by western blotting.

RESULTS

SNHG6 was significantly up-regulated in CRC samples. The knockdown of SNHG6 reduced the proliferation of CRC cells and promoted the apoptosis, whereas the over-expression of SNHG6 had the opposite effect. SNHG6 could bind with all the four members of the miR-181 family, and expression in miR-181 family members was significantly down-regulated in CRC samples. SNHG6 expression was negatively correlated with the miR-181 family member expression in CRC samples. Moreover, over-expressed SNHG6 significantly counteracted the inhibitory effect of miR-181 mimics on CRC cell proliferation, as well as the promoting effect on apoptosis. Furthermore, SNHG6 over-expression and knockdown can promote and inhibit JAK2 expression, respectively, and miR-181 family member function is opposite to that of SNHG6 by repressing JAK2.

CONCLUSIONS

SNHG6 can exert a cancer-promoting effect in CRC by targeting miR-181 family members and up-regulating JAK2.

Long Non-Coding Small Nucleolar RNA Host Genes (SNHGs) in Endocrine-Related Cancers

Long non-coding RNAs (lncRNAs) are emerging regulators of a diverse range of biological processes through various mechanisms. Genome-wide association studies of tumor samples have identified several lncRNAs, which act as either oncogenes or tumor suppressors in various types of cancers. Small nucleolar RNAs (snoRNAs) are predominantly found in the nucleolus and function as guide RNAs for the processing of transcription. As the host genes of snoRNAs, lncRNA small nucleolar RNA host genes (SNHGs) have been shown to be abnormally expressed in multiple cancers and can participate in cell proliferation, tumor progression, metastasis, and chemoresistance. Here, we review the biological functions and emerging mechanisms of SNHGs involved in the development and progression of endocrine-related cancers including thyroid cancer, breast cancer, pancreatic cancer, ovarian cancer and prostate cancer.

The prognostic value of lncRNA SNHG6 in cancer patients

Background

Although tremendous improvement has been seen in cancer diagnosis and treatment, its morbidity and mortality is still high due to lack of ideal biomarkers. An increasing number of studies have demonstrated that the expression of lncRNA small nucleolar RNA host gene 6 (SNHG6) has significantly negative correlation with various cancer prognosis. The present meta-analysis was aimed to clarify the potential of clinical application of SNHG6 in cancers.

Methods

A detailed literature review was conducted by searching through PubMed and Web of Science databases. The expression level of SNHG6, clinicopathological features and survival outcomes were extracted from eligible studies. Pooled analysis was performed with a DerSimonian-Laird random-effect model. The results were further validated through the Cancer Genome Atlas (TCGA) dataset.

Results

Five studies with a total of 487 cases were finally included in this meta-analysis. The results demonstrated that a high expression of SNHG6 was significantly associated with an increased risk of poor overall survival (OS) in cancer patients (HR = 2.06, 95% CI 1.56–2.73). Similar results from the TCGA dataset further confirmed our findings.

Conclusions

Overexpressed SNHG6 was significantly associated with poor prognosis in various cancers. Therefore, SNHG6 may become a novel molecular target for treatment and prognostic evaluation.

LncRNA SNHG6 plays an oncogenic role in colorectal cancer and can be used as a prognostic biomarker for solid tumors

Small nucleolar RNA host gene 6 (SNHG6) has been recognized as an oncogene in numerous cancers and overexpression of SNHG6 was found to promote colorectal cancer (CRC). Hence, we performed a meta-analysis to examine the clinical importance of the long noncoding RNA (lncRNA) SNHG6. Moreover, comprehensive identification of RNA-binding proteins-mass spectrometry (ChIRP-MS) was conducted to explore the carcinogenic mechanism of lncRNA SNHG6 in CRC. Fourteen studies conducted on 1,139 patients were included in this meta-analysis. We also constructed the protein-protein interactive (PPI) network in string based on the ChIRP-MS results and cytoscape was used to identify core modules in the PPI network, which were then analyzed using the bioinformatics websites, cancer single-cell state atlas (CancerSEA) and G:profilter. The clinical outcomes of the meta-analysis indicated that higher expression of SNHG6 was related with a poorer survival outcome (overall survival: hazard ratio (HR) = 1.92; 95% confidence interval [Cl]: 1.48, 2.49; p < .0001; disease-free survival: HR = 1.84; 95% Cl: 1.02, 3.34; p = .044), higher tumor stage (odds ratio [OR] = 3.35; 95% Cl: 2.57, 4.37; p < .0001), distant metastasis (OR = 1.83; 95% Cl: 1.11, 2.99; p = .017) and lymph node metastasis (OR = 1.33; 95% Cl: 0.93, 1.89; p = .119). The ChIRP-MS results showed that core Module 1 of the PPI was significant in ribosomes and core Module 2 was mainly related to spliceosomes and messenger RNA processing. In conclusion, a higher expression of SNHG6 was found to be associated with a poorer survival outcome, high tumor stage, and distant metastasis in various solid tumors. SNHG6 was also found to be able to affect the processes of transcription and translation to promote CRC.

The Interaction Between lncRNA SNHG6 and hnRNPA1 Contributes to the Growth of Colorectal Cancer by Enhancing Aerobic Glycolysis Through the Regulation of Alternative Splicing of PKM

Background: Small nucleolar RNA host gene 6 (SNHG6) acts as a carcinogenic gene in colorectal cancer (CRC). However, previous studies on the mechanism by which long non-coding RNA (lncRNA) SNHG6 exerts its carcinogenic effect in CRC have not involved the direct interaction between SNHG6 and proteins, which is a very important carcinogenic mechanism of lncRNAs. Hence, our study conducted a comprehensive RNA-binding proteins-mass spectrometry (ChIRP-MS) analysis on SNHG6 to further explore its carcinogenic mechanism in CRC. Methods: Proteins that interact with SNHG6 were found using ChIRP-MS analysis and were used to construct the protein-protein interactive (PPI) network using STRING, while the core module of the PPI network was identified using the MCODE plugin in Cytoscape. Pathway enrichment analyses, using WebGestalt, were performed on proteins and RNAs that were found to be associated with the expression of SNHG6 or which directly interacted with SNHG6. Finally, CatRAPID, miRbase, and TargetScanHuman were used to identify the sites of interaction between SNHG6, heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1), and pyruvate kinase M (PKM) mRNA. Results: The expression of SNHG6 in CRC was found to be higher than that of normal tissues and was positively correlated with a poor prognosis (p < 0.05). A total of 467 proteins that are able to interact with SNHG6 in CRC cells were identified using ChIRP-MS analysis and were used to create a PPI network, within which a core module composed of 44 proteins that performed the function of splicing mRNA, including hnRNPA1, was found to be positively correlated with SNHG6 (p < 0.05). The results of the pathway enrichment analyses suggested that SNHG6 played an important role in the metabolism of CRC by affecting the expression of PKM and SNHG6. The increase in the ratio of PKM2/PKM1 was proven using quantitative real-time polymerase chain reaction analysis. Further exploration suggested that SNHG6 could bind to hnRNPA1 and PKM. Conclusion: SNHG6 was found to be able to target the mRNA of PKM as well as induce hnRNPA1 to specifically splice PKM mRNA, which increased the proportion of PKM2/PKM1, which may be an important carcinogenic mechanism in CRC that proceeds through the enhancement of aerobic glycolysis in CRC cells.

Long Noncoding RNA SNHG6 Promotes Proliferation and Inhibits Apoptosis in Non-small Cell Lung Cancer Cells by Regulating miR-490-3p/RSF1 Axis

Background: Nonsmall cell lung cancer (NSCLC) is a malignant cancer type and has developed into the leading cause of cancer-related death worldwide. Small nucleolar RNA host gene 6 (SNHG6) has been identified as an oncogene in multiple cancers. However, the functions of SNHG6 in tumorigenesis and progression of NSCLC are still poorly understood. Materials and Methods: The expression of SNHG6, miR-490-3p, and remodeling and spacing factor 1 (RSF1) in NSCLC tumors and cells was measured by quantitative real-time polymerase chain reaction. The correlation between miR-490-3p and SNHG6 or RSF1 was analyzed by Pearson's correlation coefficient. Luciferase reporter assay was employed for verifying the interaction between miR-490-3p and SNHG6 or RSF1. Cell viability was examined by 3-(4, 5)-dimethylthiazole-2-y1)-2, 5-biphenyl tetrazolium bromide (MTT) assay. Cell apoptosis was evaluated by flow cytometry and Western blot, respectively. Protein expression of RSF1, Bcl-2, Bax, and cleaved caspase-3 (cleaved casp-3) was detected by Western blot assay. Xenograft mice models were established by subcutaneously injecting H460 cells stably transfected with sh-SNHG6 and sh-NC. Results: SNHG6 and RSF1 expression were upregulated, whereas miR-490-3p was downregulated in NSCLC tumors and cell lines compared with normal tissues and cells. Pearson's correlation coefficient analysis indicated that miR-490-3p was correlated with SNHG6 and RSF1 inversely. Then, luciferase reporter assay confirmed the interaction between miR-490-3p and SNHG6 or RSF1. More importantly, the rescue experiments clarified that miR-490-3p inhibitor could relieve SNHG6 silencing-mediated inhibition on proliferation and promotion on apoptosis in NSCLC. In addition, the authors discovered that SNHG6 promoted cell progression by regulating miR-490-3p/RSF1 axis. However, SNHG6 knockdown hindered tumor growth in vivo by regulating RSF1 by targeting miR-490-3p. Conclusion: The authors demonstrated that SNHG6 promoted proliferation and inhibits apoptosis in NSCLC by regulating miR-490-3p/RSF1 axis, representing promising targeted therapeutic strategies against NSCLC.

Long non-coding RNA SNHG6 promotes the growth and invasion of non-small cell lung cancer by downregulating miR-101-3p

BACKGROUND

The aim of this study was to determine the function of long non-coding RNA small nucleolar RNA host gene 6 (SNHG6) in non-small cell lung cancer (NSCLC) and its underlying mechanisms.

METHODS

The association of SNHG6 or miR-101-3p with clinicopathological characteristics and prognosis in patents with NSCLC was assessed by TCGA dataset. Cell proliferation and invasion were evaluated by MTT and Transwell assays and SNHG6-specific binding with miR-101-3p was verified by bioinformatic analysis, luciferase gene report and RNA immunoprecipitation assays. qRT-PCR and Western blot was used to assess the effects of SNHG6 on the expression of miR-101-3p and chromodomain Y like (CDYL) in NSCLC cells. A xenograft tumor model in vivo was established to observe the effects of SNHG6 knockdown on tumor growth.

RESULTS

We found that increased expression of SNHG6 was associated with pathological stage and lymph node infiltration, and acted as an independent prognostic factor of tumor recurrence in patients with NSCLC. Silencing SNHG6 expression repressed cell growth and invasion in vitro and in vivo, but overexpression of SNHG6 reversed these effects. Furthermore, SNHG6 was identified to act as a sponge of miR-101-3p, which could reduce cell proliferation and attenuate SNHG6-induced CDYL expression. Low expression of miR-101-3p or high expression of CDYL was related to poor survival in patients with NSCLC.

CONCLUSIONS

Our findings demonstrated that lncRNA SNHG6 contributed to the proliferation and invasion of NSCLC by downregulating miR-101-3p.

The Prognostic Significance of Metabolic Syndrome and a Related Six-lncRNA Signature in Esophageal Squamous Cell Carcinoma

Background: Metabolic syndrome (MetS) is associated with the development of esophageal squamous cell carcinoma (ESCC), and long non-coding RNAs (lncRNAs) are involved in a variety of mechanisms of MetS and tumor. This study will explore the prognostic effect of MetS and the associated lncRNA signature on ESCC.

Methods: Our previous RNA-chip data (GSE53624, GSE53622) for 179 ESCC patients were reanalyzed according to MetS. The recurrence-free survival (RFS) was collected for these patients. The status of the MetS-related tumor microenvironment was analyzed with the CIBERSORT and ESTIMATE algorithms. A lncRNA signature was established with univariate and multivariate Cox proportional hazards regression (PHR) analysis and verified using the Kaplan–Meier survival curve analysis and time-dependent receiver operating characteristic (ROC) curves. A clinical predictive model was constructed based on multiple risk factors, evaluated using C-indexes and calibration curves, and verified using data from the GEO and TCGA databases.

Results: The results showed that MetS was an independent risk factor for ESCC patients conferring low OS and RFS. Tumor microenvironment analysis indicated that patients with MetS have high stromal scores and M2 macrophage infiltration. A six-lncRNA signature was established by 60 ESCC patients randomly selected from GSE53624 and identified with an effective predictive ability in validation cohorts (59 patients from GSE53624 and 60 patients from GSE53622), subgroup analysis, and ESCC patients from TCGA. MetS and the six-lncRNA signature could be regarded as independent risk factors and enhanced predictive ability in the clinical predictive model.

Conclusions: Our results indicated that MetS was associated with poor prognosis in ESCC patients, and the possible mechanism was related to changes in the tumor microenvironment. MetS and the six-lncRNA signature could also serve as independent risk factors with available clinical application value.

Long Noncoding RNA SNHG6 Functions as an Oncogene in Non-Small Cell Lung Cancer via Modulating ETS1 Signaling

Background

Non-small cell lung cancer (NSCLC) is a great threat to human health and the biology of the NSCLC still remains largely unknown. Aberrantly expressed long non-coding RNA (lncRNA) Small nucleolar RNA host gene 6 (SNHG6) was involved in the tumorigenesis and progression of various cancers. The aim of this study is to investigate the roles of SNHG6 in NSCLC.

Methods

qRT-PCR and Western blot assays were applied to detect gene expressions. Cell proliferation and migration assays were used to analyze the gene functions. Luciferase reporter assay, RNA Immunoprecipitation assay and Chromatin immunoprecipitation assay were performed to investigate the molecular mechanism.

Results

We found that SNHG6 expression was significantly increased in NSCLC tissues and cell lines and its high expression was correlated with malignant features of NSCLC. In in vitro assays, knockdown of SNHG6 significantly depressed the proliferation vitality and migration activity of NSCLC cells. Research on mechanisms revealed that SNHG6 exerted its tumorigenesis role by promoting ETS1 expression via competitively binding with miR-944 and miR-181d-5p. We also demonstrated that ETS1 enhanced the expression of WIPF1 via binding to its promoter and SNHG6 could thereby regulate the expression of ETS1 target genes including WIPF1, MMP2 and MMP9.

Conclusion

Our study illustrates that SNHG6 is an oncogene in NSCLC and involved in NSCLC tumorigenesis by regulating ETS1 signaling via miR-944 and miR-181d-5p.

Prognostic and clinicopathological significance of SNHG6 in human cancers: a meta-analysis

Background

Recently, accumulating evidence has suggested that the aberrant expression of SNHG6 exists in a variety of tumors and has a correlation with poor clinical outcomes across cancer patients. Considering the inconsistent data among published studies, we aim to assess the prognostic effect of SNHG6 on malignancies.

Methods

We retrieved relevant publications in Web of Science, Embase, MEDLINE, PubMed and Cochrane Library based on predefined selection criteria, up to October 1, 2019. Pooled hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were utilized to evaluate the correlation between SNHG6 and overall survival (OS), recurrence-free survival (RFS) and progression-free survival (PFS) as well as clinicopathology.

Results

In total, 999 patients from 14 articles were enrolled in our meta-analysis. The results revealed that augmented SNHG6 expression was significantly correlated with poor OS (HR = 2.20, 95% CI = 1.76–2.75, P < 0.001) and RFS (HR = 3.10, 95% CI = 1.90–5.07, P < 0.001), but not with PFS (HR = 2.11, 95% CI = 0.82–5.39, P = 0.120). In addition to lung cancer and ovarian cancer, subgroup analysis showed that the prognostic value of SNHG6 across multiple tumors was constant as the tumor type, sample size, and methods of data extraction changed. Moreover, cancer patients with enhanced SNHG6 expression were prone to advanced TNM stage (OR = 3.31, 95% CI = 2.46–4.45, P < 0.001), distant metastasis (OR = 4.67, 95% CI = 2.98–7.31, P < 0.001), lymph node metastasis (OR = 2.59, 95% CI = 1.41–4.77, P = 0.002) and deep tumor invasion (OR = 3.75, 95% CI = 2.10–6.69, P < 0.001), but not associated with gender, histological grade and tumor size.

Conclusions

SNHG6 may serve as a promising indicator in the prediction of prognosis and clinicopathological features in patients with different kinds of tumors.

The function of SNHG7/miR-449a/ACSL1 axis in thyroid cancer

Thyroid cancer (TC) has been characterized as the most common malignant malady of the endocrine system. Small nucleolar RNA host gene 7 (SNHG7) has been reported to serve as a key regulator in a large number of human cancer types, but its role in TC and the underlying regulatory mechanism have never been evaluated yet. The present study indicated that the expression of SNHG7 was markedly higher in TC cell lines. Knockdown of SNHG7 led to a suppression of TC cell progression and migration. Acyl-CoA synthetase long-chain family member 1 (ACSL1) has also been demonstrated as an oncogene in many cancers. Herein an inhibition of ACSL1 after SNHG7 knockdown was captured. Further, the suppressing effects of SNHG7 knockdown on TC cell processes were counteracted by ACSL1 overexpression. Data from online bioinformatics analysis, RNA immunoprecipitation, and luciferase reporter assays validated the interaction between microRNA-449a (miR-449a) and SNHG7 or ACSL1. It was also verified that SNHG7 sequestered miR-449a and therefore elevated ACSL1 expression levels. To conclude, the current study indicated that SNHG7 promoted proliferation and migration of TC cells by sponging miR-449a and therefore upregulating ACSL1. The present study may provide more explorations about the molecular regulation mechanism of long noncoding RNAs in TC progression.

Identification of breast cancer risk modules via an integrated strategy

Breast cancer is one of the most common malignant cancers among females worldwide. This complex disease is not caused by a single gene, but resulted from multi-gene interactions, which could be represented by biological networks. Network modules are composed of genes with significant similarities in terms of expression, function and disease association. Therefore, the identification of disease risk modules could contribute to understanding the molecular mechanisms underlying breast cancer. In this paper, an integrated disease risk module identification strategy was proposed according to a multi-objective programming model for two similarity criteria as well as significance of permutation tests in Markov random field module score, function consistency score and Pearson correlation coefficient difference score. Three breast cancer risk modules were identified from a breast cancer-related interaction network. Genes in these risk modules were confirmed to play critical roles in breast cancer by literature review. These risk modules were enriched in breast cancer-related pathways or functions and could distinguish between breast tumor and normal samples with high accuracy for not only the microarray dataset used for breast cancer risk module identification, but also another two independent datasets. Our integrated strategy could be extended to other complex diseases to identify their risk modules and reveal their pathogenesis.