Long non-coding RNA SNHG1 indicates poor prognosis and facilitates disease progression in acute myeloid leukemia

The Role of Long Noncoding RNAs in Progression of Leukemia: Based on Chromosomal Location

Long non-coding RNA [LncRNA] dysregulation has been seen in many human cancers, including several kinds of leukemia, which is still a fatal disease with a poor prognosis. LncRNAs have been demonstrated to function as tumor suppressors or oncogenes in leukemia. This study covers current research findings on the role of lncRNAs in the prognosis and diagnosis of leukemia. Based on recent results, several lncRNAs are emerging as biomarkers for the prognosis, diagnosis, and even treatment outcome prediction of leukemia and have been shown to play critical roles in controlling leukemia cell activities, such as proliferation, cell death, metastasis, and drug resistance. As a result, lncRNA profiles may have superior predictive and diagnostic potential in leukemia. Accordingly, this review concentrates on the significance of lncRNAs in leukemia progression based on their chromosomal position.

LncRNA SNHG1: role in tumorigenesis of multiple human cancers

Small nucleolar RNA host gene 1 (SNHG1) is an important member of the SNHG family. This family is composed of a group of host genes that can be processed into small nucleolar RNAs and play important biological functions. In an oncogenic role, the SNHG1 expression is increased in various cancers, which has immense application prospects in the diagnosis, treatment, and prognosis of malignant tumors. In this review, we have summarized the role and molecular mechanism of SNHG1 in the development of various cancers. In addition, we have emphasized the clinical significance of SNHG1 in cancers in our article. This molecule is expected to be a new marker for potential usage in the diagnosis, prognosis, and treatment of cancer.

The Roles of SNHG Family in Osteoblast Differentiation

Small nucleolar RNA host genes (SNHGs), members of long-chain noncoding RNAs (lncRNAs), have received increasing attention regarding their roles in multiple bone diseases. Studies have revealed that SNHGs display unique expression profile during osteoblast differentiation and that they could act as promising biomarkers of certain bone diseases, such as osteoporosis. Osteogenesis of mesenchymal stem cells (MSCs) is an important part of bone repair and reconstruction. Moreover, studies confirmed that the SNHG family participate in the regulation of osteogenic differentiation of MSCs in part by regulating important pathways of osteogenesis, such as Wnt/β-catenin signaling. Based on these observations, clarifying the SNHG family's roles in osteogenesis (especially in MSCs) and their related mechanisms would provide novel ideas for possible applications of lncRNAs in the diagnosis and treatment of bone diseases. After searching, screening, browsing and intensive reading, we uncovered more than 30 papers related to the SNHG family and osteoblast differentiation that were published in recent years. Here, our review aims to summarize these findings in order to provide a theoretical basis for further research.

Small but strong: Pivotal roles and potential applications of snoRNAs in hematopoietic malignancies

Small nucleolar RNAs (snoRNAs) belong to a family of noncoding RNAs that are 60-300 nucleotides in length, and they are classified into two classes according to their structure and function: C/D box snoRNAs, playing an essential role in 2’-O-methylation modification on ribosomal RNA; H/ACA box snoRNAs, involved in the pseudouridylation of rRNA. SnoRNAs with unclear functions, no predictable targets, and unusual subcellular locations are called orphan snoRNAs. Recent studies have revealed abnormal expression and demonstrated the pivotal roles of snoRNAs and their host genes in various types of hematological malignancies. This review discusses recent discoveries concerning snoRNAs in a variety of hematological malignancies, including multiple myeloma, lymphoma and leukemia, and sheds light on the application of snoRNAs as diagnostic and prognostic markers as well as therapeutic targets of hematological malignancies in the future.

Long Noncoding RNA Small Nucleolar RNA Host gene 1 is not Only Overexpressed, But Also Correlates with Increased White Blood Cell Count, Deteriorate Induction Treatment Response and Poor Survival Profile in Adult Acute Myeloid Leukemia Patients

Objective

Long non-coding RNA small nucleolar RNA host gene 1 (lnc-SNHG1) is involved in leukemogenesis via mediating multiple pathways. The current study aimed to further explore its clinical role concerning disease risk, clinical features, and prognostication in patients with acute myeloid leukemia (AML).

Material and Methods

Generally, 161 adult AML patients, 50 disease controls (DC), and 50 healthy controls (HC) were enrolled; bone marrow mononuclear cells (BMMCs) were collected. Subsequently, a reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to measure the lnc-SNHG1 expression.

Results

Lnc-SNHG1 expression was higher in AML patients than that in DC and HC (both P<0.001), with a good value in distinguishing AML patients from DC and HC (area under the curve (AUC) of 0.726 and 0.884, respectively). Moreover, lnc-SNHG1 expression was positively associated with white blood cell (WBC) count (P=0.008) but not correlated with other clinical features such as cytogenetics, molecule-genetics, and risk stratifications, etc. (all P>0.05). Lnc-SNHG1 expression was associated with lower complete remission (CR) rate (P=0.001). In detail, patients with lnc-SNHG1 expression at quantile-4 had the worst CR rate compared to patients with lnc-SNHG1 expression at quantile-1, quantile-2, and quantile-3 (all P<0.05). Besides, lnc-SNHG1 expression was correlated with unsatisfied event-free survival (P<0.001) and overall survival (P=0.002), which were worst in patients with lnc-SNHG1 expression at quantile-4 compared with patients with lnc-SNHG1 expression at quantile-1, quantile-2 and quantile-3 (all P<0.05).

Conclusion

Lnc-SNHG1 overexpression is associated with elevated WBC, deteriorated induction treatment response, and poor survival profile in AML patients, which would further serve as a potential indicator for AML.

LncRNA SNHG12 promotes the development and progression of colon cancer by regulating the miR-15a/PDK4 axis

Colon cancer is a common gastrointestinal tumor with complex pathological process. Recently, the relationship between long non-coding RNA (lncRNA) and colon cancer has attracted more and more attention, whereas the underlying molecular mechanism is still poorly understood. Here, we found that the expression of lncRNA small nucleolar RNA host gene 12 (SNHG12) was markedly upregulated in colon cancer samples compared to normal adjacent tissues. Notably, patients with low expression of SNHG12 displayed higher survival rate than those with high expression of SNHG12. Further researches revealed that knockdown of SNHG12 suppressed the malignant phenotype of colon cancer cells. Interestingly, SNHG12 could function as a sponge to specifically bind to microRNA-15a (miR-15a). Moreover, we confirmed that pyruvate dehydrogenase kinase 4 (PDK4) is a direct target gene of miR-15a. Finally, inhibiting miR-15a expression largely abolished the effect of SNHG12 silencing on colon cancer cells. In conclusion, our data uncovered the critical role of SNHG12 in the development and progression of colon cancer through regulating the miR-15a/PDK4 axis, therefore providing a promising target for treating this disease.

Long noncoding RNAs have pivotal roles in chemoresistance of acute myeloid leukemia

Many patients with acute myeloid leukemia (AML) experience poor outcomes following traditional high-dose chemotherapies and complete remission rates remain suboptimal. Chemoresistance is an obstacle to effective chemotherapy and the precise mechanisms involved remain to be determined. Recently, long noncoding RNAs (lncRNAs) have been identified as relevant factors in the development of drug resistance in patients with AML. Furthermore, accumulating data support the importance of lncRNAs as potentially useful novel therapeutic targets in many cancers. Here, we review the role of lncRNAs in the development and induction of the chemoresistance in AML, and suggest lncRNAs as novel molecular markers for diagnosis, prediction of patient response to chemotherapy, and novel therapeutic targets for AML.

Large Scale Molecular Studies of Pituitary Neuroendocrine Tumors: Novel Markers, Mechanisms and Translational Perspectives

Simple Summary

Pituitary neuroendocrine tumors are non-cancerous tumors of the pituitary gland, that may overproduce hormones leading to serious health conditions or due to tumor size cause chronic headache, vertigo or visual impairment. In recent years pituitary neuroendocrine tumors are studied with the latest molecular biology methods that simultaneously investigate a large number of factors to understand the mechanisms of how these tumors develop and how they could be diagnosed or treated. In this review article, we have studied literature reports, compiled information and described molecular factors that could affect the development and clinical characteristics of pituitary neuroendocrine tumors, discovered factors that overlap between several studies using large scale molecular analysis and interpreted the potential involvement of these factors in pituitary tumor development. Overall, this study provides a valuable resource for understanding the biology of pituitary neuroendocrine tumors.

Abstract

Pituitary neuroendocrine tumors (PitNETs) are non-metastatic neoplasms of the pituitary, which overproduce hormones leading to systemic disorders, or tumor mass effects causing headaches, vertigo or visual impairment. Recently, PitNETs have been investigated in large scale (exome and genome) molecular analyses (transcriptome microarrays and sequencing), to uncover novel markers. We performed a literature analysis on these studies to summarize the research data and extrapolate overlapping gene candidates, biomarkers, and molecular mechanisms. We observed a tendency in samples with driver mutations (GNAS, USP8) to have a smaller overall mutational rate, suggesting driver-promoted tumorigenesis, potentially changing transcriptome profiles in tumors. However, direct links from drivers to signaling pathways altered in PitNETs (Notch, Wnt, TGF-β, and cell cycle regulators) require further investigation. Modern technologies have also identified circulating nucleic acids, and pinpointed these as novel PitNET markers, i.e., miR-143-3p, miR-16-5p, miR-145-5p, and let-7g-5p, therefore these molecules must be investigated in the future translational studies. Overall, large-scale molecular studies have provided key insight into the molecular mechanisms behind PitNET pathogenesis, highlighting previously reported molecular markers, bringing new candidates into the research field, and reapplying traditional perspectives to newly discovered molecular mechanisms.

Competing Endogenous RNA Networks as Biomarkers in Neurodegenerative Diseases

Protein aggregation is classically considered the main cause of neuronal death in neurodegenerative diseases (NDDs). However, increasing evidence suggests that alteration of RNA metabolism is a key factor in the etiopathogenesis of these complex disorders. Non-coding RNAs are the major contributor to the human transcriptome and are particularly abundant in the central nervous system, where they have been proposed to be involved in the onset and development of NDDs. Interestingly, some ncRNAs (such as lncRNAs, circRNAs and pseudogenes) share a common functionality in their ability to regulate gene expression by modulating miRNAs in a phenomenon known as the competing endogenous RNA mechanism. Moreover, ncRNAs are found in body fluids where their presence and concentration could serve as potential non-invasive biomarkers of NDDs. In this review, we summarize the ceRNA networks described in Alzheimer's disease, Parkinson's disease, multiple sclerosis, amyotrophic lateral sclerosis and spinocerebellar ataxia type 7, and discuss their potential as biomarkers of these NDDs. Although numerous studies have been carried out, further research is needed to validate these complex interactions between RNAs and the alterations in RNA editing that could provide specific ceRNET profiles for neurodegenerative disorders, paving the way to a better understanding of these diseases.

Identification of Long Non-Coding RNA SNHG Family as Promising Prognostic Biomarkers in Acute Myeloid Leukemia

Background

Small nucleolar RNA host gene (SNHG) family members are newly recognized lncRNAs, which have been revealed to be oncogenes in several cancers. However, little studies investigated the expression and clinical implications of SNHGs in AML.

Methods

Herein, we systemically determined the prognostic role of the expression of SNHG family members in acute myeloid leukemia (AML).

Results

Among the expression of all SNHG family members, we identified that only SNHG7 and SNHG12 expression were found to have prognostic effects on overall survival (OS) and leukemia-free survival (LFS) in AML by Cox regression univariate analysis. Furthermore, Kaplan-Meier analysis showed that SNHG7 higher-expressed cases had markedly longer OS and LFS time than SNHG7 lower-expressed cases, whereas SNHG12 higher-expressed cases had markedly shorter OS and LFS time than SNHG12 lower-expressed cases. Interestingly, SNHG7 and SNHG12 expression were also associated with several prognosis-related clinical/molecular features such as white blood cell counts, FAB/cytogenetic classifications, IDH1 mutation, RUNX1 mutation, and NPM1 mutation. Despite the associations, Cox regression multivariate analysis confirmed the independent prognostic impact of SNHG7 and SNHG12 expression in AML. Notably, we further validated that both SNHG7 and SNHG12 expression was significantly increased in newly diagnosed AML patients.

Conclusion

Our findings demonstrated that SNHG7 and SNHG12 expression act as independent prognostic indicators in AML.

Long Noncoding RNA SNHG1 Contributes to the Promotion of Prostate Cancer Cells Through Regulating miR-377-3p/AKT2 Axis

Background: Long noncoding RNAs could serve as a candidate target for prostate cancer (PCa) diagnosis and treatment. The current study aimed to investigate the role and functions of SNHG1 in PCa cells. Materials and Methods: Abnormal expression of SNHG1, survival analysis, and target gene were determined or predicted by bioinformatics techniques. Gene expressions at transcriptional and translational levels were determined by Quantitative Real-time PCR and Western blotting, respectively. Cell viability, growth, and apoptosis rate were detected by Cell Counting Kit-8, colony formation assay and flow cytometry. Results: The results showed that SNHG1 was highly expressed in PCa tissues, which was accompanied by decreased miR-377-3p expression and poor overall survival rate, and that miR-377-3p was predicted as the target of SNHG1 in PCa cells. Moreover, SNHG1 counteracted the effects of miR-377-3p on inhibiting cell growth and promoting apoptosis of PCa cells. Furthermore, miR-377-3p counteracted the effects of AKT2 on promoting cell viability, growth, and suppressing apoptosis of PCa cells. In addition, AKT2 expression was proved to be regulated by miR-377-3p. Conclusions: The SNHG1/miR-377-3p/AKT2 regulatory axis in PCa cells was disclosed. The upregulated AKT2 might be a result of dysregulated interaction balance between the expressions of miR-377-3p and SNHG1. Based on such discoveries, the intervention of SNHG1/miR-377-3p/AKT2 axis could be further explored in the treatment of PCa.