Novel lncRNA PSMG3‑AS1 functions as a miR‑143‑3p sponge to increase the proliferation and migration of breast cancer cells

Biological functions and potential mechanisms of miR‑143‑3p in cancers (Review)

In recent years, microRNAs (miRNAs or miRs) have been increasingly studied for their role in cancer and have shown potential as cancer biomarkers. miR‑143‑3p and miR‑143‑5p are the mature miRNAs derived from pre‑miRNA‑143. At present, there are numerous studies on the function of miR‑143‑3p in cancer progression, but there are no systematic reviews describing the function of miR‑143‑3p in cancer. It is widely considered that miR‑143‑3p is downregulated in most malignant tumors and that upstream regulators can act on this gene, which in turn regulates the corresponding target to act on the tumor. In addition, miRNA‑143‑3p can regulate target genes to affect the biological process of tumors through various signaling pathways, such as the PI3K/Akt, Wnt/β‑catenin, AKT/STAT3 and Ras‑Raf‑MEK‑ERK pathways. The present review comprehensively described the biogenesis of miR‑143‑3p, the biological functions of miR‑143‑3p and the related roles and mechanisms in different cancer types. The potential of miR‑143‑3p as a biomarker for cancer was also highlighted and valuable future research directions were discussed.

Long non-coding RNA PSMG3 Antisense RNA 1 is correlated with oral squamous cell carcinoma and regulates cancer cell proliferation by targeting premature microRNA-141

Oral squamous cell carcinoma (OSCC) is common worldwide. In this study, the interaction of microRNA-141 (miR-141) with long non-coding RNA (lncRNA) PSMG3 Antisense RNA 1 (PSMG3-AS1) in OSCC was explored. RT-qPCR was used to analyze the expression of PSMG3-AS1 and miR-141 (both mature and premature) in OSCC. Nuclear fractionation assay was applied to detect PSMG3-AS1 in subcellular locations. RNA pull-down assay was performed to evaluate the binding of miR-141 to PSMG3-AS1. Overexpression assay followed by RT-qPCR was performed to explore the role of PSMG3-AS1 in maturation of miR-141. The function of PSMG3-AS1 and miR-141 in regulating OSCC cell proliferation was assessed by BrdU assay. The results showed that PSMG3-AS1 was highly upregulated in OSCC and miR-141 was downregulated in OSCC. However, no alteration in the expression of premature miR-141 was observed in OSCC. Premature miR-141 was found to directly bind to PSMG3-AS1. Overexpression of PSMG3-AS1 suppressed the maturation of miR-141. PSMG3-AS1 increased OSCC cell proliferation and tumor growth and suppressed the inhibitory role of miR-141 in cell proliferation and tumor growth. Therefore, PSMG3-AS1 may inhibit the maturation of miR-141 to promote OSCC cell proliferation.

Prognostic and Immune Infiltration Value of Proteasome Assembly Chaperone (PSMG) Family Genes in Lung Adenocarcinoma

The complexity of lung adenocarcinoma (LUAD) including many interacting biological processes makes it difficult to find therapeutic biomarkers for treatment. Previous studies demonstrated that PSMG (proteasome assembly chaperone) family members regulate the degradation of abnormal proteins. However, transcript expressions of this gene family in LUAD still need to be more fully investigated. Therefore, we used a holistic bioinformatics approach to explore PSMG genes involved in LUAD patients by integrating several high-throughput databases and tools including The Cancer Genome Atlas (TCGA), and Kaplan-Meier plotter database. These data demonstrated that PSMG3 and PSMG4 were expressed at significantly higher levels in neoplastic cells than in normal lung tissues. Notably, increased expressions of these proteins were correlated with poor prognoses of lung cancer patients, which probably confirmed their fundamental roles in the staging of LUAD tumors. Meanwhile, it was also indicated that there were positive correlations between PSMG family genes and the immune response, metabolism of ubiquinone, cell cycle regulatory pathways, and heat shock protein 90 (HSP90)/phosphatidylinositol 3-kinase (PI3K)/Wnt signaling. Experimental data also confirmed that the knockdown of PSMG4 in LUAD cell lines decreased cell proliferation and influenced expressions of downstream molecules. Collectively, this study revealed that PSMG family members are novel prognostic biomarkers for LUAD progression, which also provide new therapeutic targets of LUAD patients.

Comparative Analysis of microRNAs that Stratify in vitro Mammary stem and Progenitor Activity Reveals Functionality of Human miR-92b-3p

Mammary stem/progenitor cells are fundamental for mammary gland development and function. However, much remains to be elucidated regarding their function in mammals beyond the traditionally studied rodents, human, and to a lesser extent, ruminants. Due to the growing appreciation for microRNAs (miRNAs) as regulators of stem cells and their progenitors, we compared miRNA expression in mammary stem/progenitor cells from mammals with varying mammary stem/progenitor activity in vitro, in order to identify miRNA candidates that regulate stem/progenitor self-renewal and function. Mammosphere-derived epithelial cells (MDECs), which are primary cell lines enriched in mammary stem and progenitor cells, were generated from six mammalian species (i.e., cow, human, pig, horse, dog, and rat) and small RNA sequencing was performed. We identified 9 miRNAs that were significantly differentially expressed in MDEC cultures with a low versus high mammary stem/progenitor activity. miR-92b-3p was selected for functional follow-up studies, as this miRNA is understudied in primary mammary cells but has well-described gene targets that are known to regulate mammary stem/progenitor activity. Altering the expression of miR-92b-3p in MDECs from species with low stem/progenitor activity (human and cow) and those with high stem/progenitor activity (dog and rat) via inhibition and overexpression, respectively, resulted in significantly decreased mammosphere formation of human MDECs, but showed no significant effects in cow, dog, or rat MDECs. This study is the first to perform small RNA sequencing in MDECs from various mammals and highlights that conserved miRNAs can have different functions in mammary stem/progenitor cells across species.

Prognosis Signature of Cuprotosis-Related lncRNAs Associated with Kidney Renal Clear Cell Carcinoma

Cuprotosis is a novel cell death mechanism that can be explored to treat various tumors. A few studies on the role of cuprotosis-related long noncoding RNA (lncRNA) in the development and prognosis of kidney renal clear cell carcinoma (KIRC) have been reported. We aimed to study the relationship between the prognosis of patients suffering from KIRC and lncRNAs associated with cuprotosis. The Cancer Genome Atlas (TCGA) database was analyzed, and the transcriptome data and clinical information on the patients with KIRC were obtained. The cuprotosis-related lncRNAs were identified by using Pearson correlation analysis, and the significant changes in the lncRNAs associated with KIRC were studied by conducting the T-test. The cuprotosis-related lncRNAs with KIRC prognostic values were identified by using the univariate Cox analysis, least absolute shrinkage and selection operator (LASSO), and support vector machine (SVM) methods. A prognostic marker composed of three cuprotosis-related lncRNAs was identified following the multivariate regression analysis method. Patients with KIRC were divided into two groups based on the expression characteristics of three cuprotosis-related lncRNAs by using the K nearest neighbor (KNN) cluster analysis method. Significant differences in survival were observed between the two groups. In addition, the results obtained following the independent prognostic analysis of the risk score (RS) and clinical correlation revealed that the three cuprotosis-related lncRNA prognostic markers could accurately predict the prognosis of patients with KIRC. The results reported herein provide new insights into the pathogenesis of KIRC and the contribution of lncRNAs associated with cuprotosis. The results also helped identify a prognostic indicator that could potentially provide information for KIRC treatment.

Identifying Autophagy-Related lncRNAs and Potential ceRNA Networks in NAFLD

Nonalcoholic fatty liver disease (NAFLD) is a common chronic disease with complex pathogenesis, which brings economic burden to the society, and there is still no effective therapy. Impaired autophagy has been implicated in the development of NAFLD. Long noncoding RNAs (lncRNAs) are also reported to play a role in the pathogenesis of NAFLD. However, the role of autophagy-related lncRNAs in NAFLD disease has not been elucidated. Here, we mined GSE135251, GSE160016, GSE130970 and GSE185062 datasets from the Gene Expression Omnibus database (GEO) and obtained the human autophagy-related gene list from the Human Autophagy Database (HADb) for in-depth bioinformatic analysis. Following differential expression analysis and intersection of the datasets, Pearson correlation analysis was performed on DElncRNAs and autophagy-related DEmRNAs to obtain autophagy-related lncRNAs, and then Starbase3.0 and TargetScan7.2 were used to construct competing endogenous RNAs (ceRNA) regulatory networks. We constructed four lncRNA-dominated ceRNA regulatory networks (PSMG3-AS1, MIRLET7BHG, RP11-136K7.2, LINC00925), and visualized with Cytoscape. Then we performed co-expression analysis of the ceRNA networks and autophagy-related genes, and functionally annotated them with Metascape. Finally, we performed receiver operating characteristic curve (ROC) analysis on lncRNAs and mRNAs within the ceRNA networks. Conclusively, our project is the first to study autophagy-related lncRNAs in NAFLD and finally mined four autophagy-related lncRNAs (PSMG3-AS1, MIRLET7BHG, RP11-136K7.2, LINC00925). We suggested that the four autophagy-related lncRNAs may be closely associated with the occurrence and development of NAFLD through the corresponding ceRNA regulatory networks. This research brings new horizons to the study of NAFLD.

MAPK1 Is Regulated by LOC102188416/miR-143-3p Axis in Dairy Goat Mammary Epithelial Cells

MicroRNA-143-3p (miR-143-3p) is one of the miRNAs involved in the growth of goat mammary epithelial cells (GMECs). In this study, Illumina/Solexa sequencing was performed to establish the lncRNA database in Laoshan dairy goats. Using the lncRNA database, long noncoding RNAs (lncRNAs) regulated by miR-143-3p were screened. In total, 4899 lncRNAs were identified, with 173 lncRNAs being differentially expressed in all three replicates. The target genes of the differentially expressed lncRNAs were annotated in GO terms and KEGG pathways. Among the differentially expressed lncRNAs, lncRNA LOC102188416 was predicted to sponge miR-143-3p and share MAPK1 as a common target gene with miR-143-3p, which was validated by dual luciferase reporter assay system and qRT-PCR. The miR-143-3p mimic significantly lowered the relative luciferase activity of psiCHECK2-LOC102188416 wildtype vector but not mutated vector, suggesting that lncRNA LOC102188416 might be a sponge of miR-143-3p, which was verified by the promotion role of lncRNA LOC102188416 siRNA (siR-LOC102188416) in the expression of miR-143-3p. It was shown that the expression of MAPK1 was downregulated by either miR-143-3p mimic or siR-LOC102188416, indicating that miR-143-3p and lncRNA LOC102188416 had a coregulatory effect on MAPK1 expression. The co-transfection of miR-143-3p inhibitor with siR-LOC102188416 reversed the decrease of MAPK1 expression regulated by siR-LOC102188416 alone, strengthening the existence of lncRNA LOC102188416/miR-143-3p/MAPK1 axis in GMECs of Laoshan dairy goats.

KRAS-related long noncoding RNAs in human cancers

KRAS is one of the most widely prevalent proto-oncogenes in human cancers. The constitutively active KRAS oncoprotein contributes to both tumor onset and cancer development by promoting cell proliferation and anchorage-independent growth in a MAPK pathway-dependent manner. The expression of microRNAs (miRNAs) and the KRAS oncogene are known to be dysregulated in various cancers, while long noncoding RNAs (lncRNAs) can act as regulators of the miRNAs targeting KRAS oncogene in different cancers and have gradually become a focus of research in recent years. In this review article, we summarize recent advances in the research on lncRNAs that have sponging effects on KRAS-targeting miRNAs as crucial mediators of KRAS expression in different cell types and organs. A deeper understanding of lncRNA function in KRAS-driven cancers is of major fundamental importance and will provide a valuable clinical tool for the diagnosis, prognosis, and eventual treatment of cancers.

LncRNAs PSMG3-AS1 and MEG3 negatively regulate each other to participate in endometrial carcinoma cell proliferation

Endometrial carcinoma (EC), also known as corpus cancer or corpus uterine cancer, is the most frequently diagnosed genital cancer among women in developed countries. Our preliminary RNA-seq analysis revealed the inverse correlation between the expression of PSMG3-AS1 and MEG3 across EC tissues, indicating the possible interaction between them. This study aimed to explore the interaction between two long non-coding RNAs (lncRNAs) PSMG3-AS1 and MEG3 in EC. Investigation of the interaction between two lncRNAs in cancer biology is a novel topic. The expression of PSMG3-AS1 and MEG3 in EC and paired non-tumor tissues from 60 EC patients were determined by RT-qPCR. Correlations between them were analyzed by Pearson's correlation coefficient. PSMG3-AS1 and MEG3 were overexpressed in EC cells to study the relationship between them. The roles of PSMG3-AS1 and MEG3 in regulating the proliferation of EC cells were assessed by CCK-8 assay. PSMG3-AS1 was upregulated, while MEG3 was downregulated in EC. Across EC tissues, the expression of PSMG3-AS1 and MEG3 were inversely correlated. In EC cells, overexpression of PSMG3-AS1 and MEG3 resulted in the downregulation of each other. In cell proliferation assay, PSMG3-AS1 promoted cell proliferation, and MEG3 inhibited cell proliferation. Moreover, the proliferation rate of cells co-transfected with PSMG3-AS1 and MEG3 expression vectors was not different from that in cells without transfections. In conclusion, PSMG3-AS1 and MEG3 may negatively regulate each other to regulate EC cell proliferation.

Expression of oncogenic long noncoding RNA PSMG3-antisense 1 in lung squamous cell carcinoma

Lung squamous cell carcinoma (LUSC) is one of the most common subtypes of lung cancer that accounts for ~50% of all lung cancer cases. Long noncoding RNA (lncRNA) PSMG3-antisense (AS) 1 has been suggested to play an important role in various types of cancer. Therefore, the aim of the present study was to investigate the role of PSMG3-AS1 using clinical specimens and data from 130 patients with LUSC. The expression levels of PSMG3-AS1 and miR-143-3p were detected in LUSC specimens, and the correlation between lncRNA PSMG3-AS1 expression and patient clinical characteristics was analyzed. Cell Counting Kit-8, Transwell migration and invasion assays were used to investigate the functional role of PSMG3-AS1 in LUSC. The mechanism of PSMG3-AS1 on LUSC cells was also investigated using a luciferase activity assay with wild-type or mutated PSMG3-AS1. PSMG3-AS1 was found to be upregulated in LUSC, and high expression was associated with positive lymph node metastasis and a higher TNM stage. The results of multivariate Cox regression analysis revealed that PSMG3-AS1 may serve as an independent prognostic indicator in LUSC. Furthermore, inhibiting PSMG3-AS1 expression reduced tumor cell proliferative, migratory and invasive abilities. Moreover, PSMG3-AS1 was found to be closely associated with miR-143-3p in LUSC, and thus may become a potential prognostic marker and therapeutic target for the treatment of LUSC in the future.

Long noncoding RNA ZBED3-AS1 restrains breast cancer progression by targeting the microRNA-513a-5p/KLF6 axis

Breast cancer (BC) is the most commonly occurring malignancy in women. This study aimed to investigate the functions of the long noncoding RNA ZBED3‐AS1 (ZBED3‐AS1) in BC and its molecular mechanisms. qRT‐PCR was conducted to access the expression of ZBED3‐AS1, microRNA‐513a‐5p (miR‐513a‐5p), and Kruppel like factor 6 (KLF6) in BC. Additionally, BC cell viability and proliferative capacity were measured by MTT and 5‐Ethynyl‐20‐deoxyuridine (EdU) assays. A transwell assay was used for evaluating BC cell migration and invasion. The interactions among ZBED3‐AS1, miR‐513a‐5p, and KLF6 in BC were confirmed by dual‐luciferase reporter assay. Furthermore, feedback approaches were performed to determine whether ZBED3‐AS1 influences BC cell behaviors by regulating the miR‐513a‐5p/KLF6 axis. The murine xenograft model was established to assess the effect of ZBED3‐AS1 on tumor growth. The expression of ZBED3‐AS1 and KLF6 was reduced, while miR‐513a‐5p expression was elevated in BC. ZBED3‐AS1 elevation attenuated the malignant behaviors of BC cells, including viability, proliferative capacity, migration, and invasion. Mechanical experiments revealed that ZBED3‐AS1 targeted miR‐513a‐5p, and miR‐513a‐5p targeted KLF6 in BC. Feedback approaches validated that miR‐513a‐5p overexpression or KLF6 depletion reversed the inhibitory effects of ZBED3‐AS1 upregulation on viability, proliferative capacity, migration, and invasion of BC cells. Furthermore, ZBED3‐AS1 elevation attenuated the tumor growth in the murine xenograft model. ZBED3‐AS1 hindered the malignant development of BC cells by regulating the miR‐513a‐5p/KLF6 axis, providing a novel therapeutic target in BC.

Multifaceted roles of long non-coding RNAs in triple-negative breast cancer: biology and clinical applications

Triple-negative breast cancer (TNBC) is a heterogeneous breast cancer subtype that lacks targeted therapy due to the absence of estrogen, progesterone, and HER2 receptors. Moreover, TNBC was shown to have a poor prognosis, since it involves aggressive phenotypes that confer significant hindrance to therapeutic treatments. Recent state-of-the-art sequencing technologies have shed light on several long non-coding RNAs (lncRNAs), previously thought to have no biological function and were considered as genomic junk. LncRNAs are involved in various physiological as well as pathological conditions, and play a key role in drug resistance, gene expression, and epigenetic regulation. This review mainly focuses on exploring the multifunctional roles of candidate lncRNAs, and their strong association with TNBC development. We also summarise various emerging research findings that establish novel paradigms of lncRNAs function as oncogenes and/or tumor suppressors in TNBC development, suggesting their role as prospective therapeutic targets.

miR-4417 targets lncRNA PSMG3-AS1 to suppress cell invasion and migration in cervical squamous cell carcinoma

Although long non-coding RNA (lncRNA) PSMG3-AS1 has been reported to participate in cancer biology, its role in cervical squamous cell carcinoma (CSCC) is unknown. The present study aimed to investigate the role of the lncRNA PSMG3-AS1 in CSCC. The expression levels of PSMG3-AS1 in both CSCC and non-tumor tissues from 64 patients with CSCC were measured by reverse transcription-quantitative PCR. The potential interaction between miR-4417 and PSMG3-AS1 was predicted using IntaRNA 2.0. Overexpression of miR-4417 and PSMG3-AS1 were achieved in CSCC cells to further explore the potential interaction between them. The effects of overexpression of miR-4417 and PSMG3-AS1 on CSCC cell invasion and migration were assessed by Transwell assay. The results revealed that PSMG3-AS1 expression was upregulated in CSCC tissues, and its high expression levels predicted a poor survival in patients with CSCC. miR-4417 expression was downregulated in CSCC tissues and was inversely correlated with PSMG3-AS1 expression. Moreover, miR-4417 was predicted to interact with PSMG3-AS1. In CSCC cells, overexpression of miR-4417 decreased the expression levels of PSMG3-AS1, while overexpression of PSMG3-AS1 did not affect miR-4417 expression. Transwell assay demonstrated that overexpression of PSMG3-AS1 increased CSCC cell invasion and migration. However, overexpression of miR-4417 inhibited CSCC cell invasion and migration, and attenuated the effects of PSMG3-AS1 overexpression in CSCC cells. In conclusion, the present study indicated that miR-4417 may target PSMG3-AS1 to suppress cancer cell invasion and migration in CSCC.

LncRNA PSMG3AS1 promotes proliferation of non-small cell lung cancer cells by sponging miR-613 to upregulate SphK1

PSMG3-AS1 is a characterized oncogenic lncRNA in breast cancer, while its role in other cancers remains unclear. This study was to investigate the role and underlying mechansim of PSMG3-AS1 in non-small cell lung cancer (NSCLC). In this study, we found that PSMG3-AS1 could interact with miR-613. The expression of PSMG3-AS1 was upregulated in NSCLC, while the expression of miR-613 was downregulated in NSCLC. However, PSMG3-AS1 and miR-613 were not significantly correlated with each other. In NSCLC cells, PSMG3-AS1 and miR-613 overexpression failed to regulate the expression of each other. Interestingly, PSMG3-AS1 overexpression led to upregulated SphK1, a downstream target of miR-613. In addition, PSMG3-AS1 overexpression reduced the inhibitory effects of miR-613 on NSCLC cell proliferation. Therefore, PSMG3-AS1 may promote the proliferation of NSCLC cells by sponging miR-613 to upregulate SphK1.

LINC00460 Is a Dual Biomarker That Acts as a Predictor for Increased Prognosis in Basal-Like Breast Cancer and Potentially Regulates Immunogenic and Differentiation-Related Genes

Breast cancer (BRCA) is a serious public health problem, as it is the most frequent malignant tumor in women worldwide. BRCA is a molecularly heterogeneous disease, particularly at gene expression (mRNAs) level. Recent evidence shows that coding RNAs represent only 34% of the total transcriptome in a human cell. The rest of the 66% of RNAs are non−coding, so we might be missing relevant biological, clinical or regulatory information. In this report, we identified two novel tumor types from TCGA with LINC00460 deregulation. We used survival analysis to demonstrate that LINC00460 expression is a marker for poor overall (OS), relapse-free (RFS) and distant metastasis-free survival (DMFS) in basal-like BRCA patients. LINC00460 expression is a potential marker for aggressive phenotypes in distinct tumors, including HPV-negative HNSC, stage IV KIRC, locally advanced lung cancer and basal-like BRCA. We show that the LINC00460 prognostic expression effect is tissue-specific, since its upregulation can predict poor OS in some tumors, but also predicts an improved clinical course in BRCA patients. We found that the LINC00460 expression is significantly enriched in the Basal-like 2 (BL2) TNBC subtype and potentially regulates the WNT differentiation pathway. LINC00460 can also modulate a plethora of immunogenic related genes in BRCA, such as SFRP5, FOSL1, IFNK, CSF2, DUSP7 and IL1A and interacts with miR-103-a-1, in-silico, which, in turn, can no longer target WNT7A. Finally, LINC00460:WNT7A ratio constitutes a composite marker for decreased OS and DMFS in Basal-like BRCA, and can predict anthracycline therapy response in ER-BRCA patients. This evidence confirms that LINC00460 is a master regulator in BRCA molecular circuits and influences clinical outcome.

LINC00221 suppresses the malignancy of children acute lymphoblastic leukemia

As the most common malignant disease in childhood, children acute lymphoblastic leukemia (ALL) is a heterogeneous disease caused by the accumulated genetic alterations. Long non-coding RNAs (lncRNAs) are reported as critical regulators in diseases. GEPIA database indicated that long intergenic non-protein coding RNA 221 (LINC00221) was conspicuously down-regulated in acute myeloid leukemia. However, its expression pattern in ALL has not been revealed. This work was carried out to study the role of LINC00221 in ALL cells. Quantitative real-time PCR (qRT-PCR) quantified LINC00221 expression in ALL cells. The function of LINC00221 in ALL was determined by ki-67 immunofluorescence staining, EdU, TUNEL, JC-1, and caspase-3/8/9 activity assays. RNA pull down and Ago2-RNA immunoprecipitation (RIP) assays investigated the interaction between miR-152-3p and LINC00221 or ATPase sarcoplasmic/endoplasmic reticulum Ca2⁺ transporting 2 (ATP2A2). Our study revealed the low expression of LINC00221 in ALL cells. Subsequently, LINC00221 was verified to bind with miR-152-3p. Moreover, functional assays pointed out that LINC00221 overexpression posed anti-proliferation and pro-apoptosis effects in ALL cells, and these effects could be separately reversed by miR-152-3p up-regulation. Afterward, LINC00221 was revealed to regulate ATP2A2 expression via sponging miR-152-3p. Additionally, ATP2A2 was verified to involve in regulating LINC00221-mediated ALL cell proliferation and apoptosis. In conclusion, LINC00221 suppressed ALL cell proliferation and boosted ALL cell apoptosis via sponging miR-152-3p to up-regulate ATP2A2.

LINC01278 is Highly Expressed in Osteosarcoma and Participates in the Development of Tumors by Mediating the miR-134-5p/KRAS Axis

Purpose

There is increasing evidence that non-coding RNAs (ncRNAs), including long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), produce a critical regulatory effect on osteosarcoma (OS). LINC01278, as a newly discovered lncRNA, is found to be highly expressed in OS, but its related mechanism remains unclear. This research, therefore, is designed to study the mechanism of LINC01278 in OS and to find potential targets for clinical use.

Methods

qRT-PCR was applied to determine the relative expression of LINC01278 and analyze its diagnostic value in OS. CCK-8, Transwell and flow cytometry were utilized for the determination of cell proliferation, migration/invasion, and apoptosis. RIP and RNA pull-down experiments were used to verify the targeted binding effect of miR-134-5p and LINC01278. The relationship between miR-134-5p and LINC01278 or KRAS was analyzed using dual luciferase reporter gene. The effects of LINC01278 on tumor growth in nude mice was analyzed by in vivo experiment.

Results

qRT-PCR showed that LINC01278 increased in OS tissues and serum, indicating poor prognosis. In addition, LINC01278 was also of high value for OS diagnosis. Functional experiments showed that LINC01278 inhibited KRAS-mediated OS cell proliferation and metastasis through miR-134-5p. Finally, the results of an in vivo animal model indicated that LINC01278 promoted OS growth.

Conclusion

LINC01278 is expressed highly in OS, and patients with high LINC01278 expression have poor prognosis. Moreover, LINC01278 can suppress the proliferation and apoptosis of OS cells through mediating miR-134-5p/KRAS axis, which is expected to become a potential therapeutic target for OS.

H19 Rises in Gastric Cancer and Exerts a Tumor-Promoting Function via miR-138/E2F2 Axis

Purpose

The aim of this paper was to investigate H19 expression in gastric cancer (GC) and its effects on the biological behavior of gastric cancer cells (GCCs), and at exploring its potential mechanism.

Methods

H19 expression in the patients’ tissues and serum was detected, and the correlation of the expression with the patients’ pathological data and survival rate was analyzed. Overexpression or inhibitory vectors of H19, microRNA-138 (miR-138) and E2F2 were constructed and transfected into GCCs to observe their effects on the cells’ proliferation, invasion and apoptosis.

Results

H19 rose in GC and was higher in GC patients with a tumor size ≥5 cm, high stages (III+IV) and lymph node metastasis. High H19 expression was associated with the poorer survival rate of the patients, so serum H19 had a certain diagnostic value for GC. H19 knockdown could inhibit GCCs to proliferate and invade and induce their apoptosis. miR-138 can be used as the target gene of H19, and E2F2 can be negatively regulated by this miR, so miR-138 knockdown or E2F2 upregulation can weaken GCCs’ biological behavior changes that were caused by H19 knockdown.

Conclusion

H19 can be used as a biological indicator for diagnosing GC and predicting patients’ poor prognosis. Additionally, it promotes GCCs to proliferate and invade through miR-138/E2F2 axis.

Hypoxia-Associated Prognostic Markers and Competing Endogenous RNA Co-Expression Networks in Breast Cancer

Objective

Many primary tumors have insufficient supply of molecular oxygen, called hypoxia. Hypoxia is one of the leading characteristics of solid tumors resulting in a higher risk of local failure and distant metastasis. It is quite necessary to investigate the hypoxia associated molecular hallmarks in breast cancer.

Materials and Methods

According to the published studies, we selected 13 hypoxia related gene expression signature to define the hypoxia status of breast cancer using ConsensusClusterPlus package based on the data from The Cancer Genome Atlas (TCGA). Subsequently, we characterized the infiltration of 24 immune cell types under different hypoxic conditions. Furthermore, the differentially expressed hypoxia associated microRNAs, mRNAs and related signaling pathways were analyzed and depicted. On this basis, a series of prognostic markers related to hypoxia were identified and ceRNA co-expression networks were constructed.

Results

Two subgroups (cluster1 and cluster2) were identified and the 13 hypoxia related gene signature were all up-regulated in cluster1. Thus, we defined the cluster1 as “hypoxic subgroup” compared with cluster2. The infiltration of CD8+ T cell and CD4+ T cell were lower in cluster1 while the nTreg cell and iTreg cell were higher, indicating that there was immunosuppressive status in cluster1. We observed widespread hypoxia-associated dysregulation of microRNAs and mRNAs. Next, a risk signature for predicting prognosis of breast cancer patients was established based on 12 dysregulated hypoxia associated prognostic genes. Two microRNAs, hsa-miR-210-3p and hsa-miR-190b, with the most significant absolute logFC value were related to unfavorable and better prognosis, respectively. Several long non-coding RNAs were predicted to be microRNA targets and positively correlated with two selected mRNAs, CPEB2 and BCL11A. Predictions based on the LINC00899/PSMG3-AS1/PAXIP1-AS1- hsa-miR-210-3p-CPEB2 and SNHG16- hsa-miR-190b-BCL11A ceRNA regulation networks indicated that the two genes might act as tumor suppressor and oncogene, respectively.

Conclusion

Hypoxia plays an important role in the initiation and progression of breast cancer. Our research provides potential mechanisms into molecular-level understanding of tumor hypoxia.

Exploring the Roles of lncRNAs in GBM Pathophysiology and Their Therapeutic Potential

Glioblastoma (GBM) remains the most devastating primary central nervous system malignancy with a median survival of around 15 months. The past decades of research have not yielded significant advancements in the treatment of GBM. In that same time, a novel class of molecules, long non-coding RNAs (lncRNAs), has been found to play a multitude of roles in cancer and normal biology. The increased accessibility of next generation sequencing technologies and the advent of lncRNA-specific microarrays have facilitated the study of lncRNA etiology. Molecular and computational methods can be applied to predict lncRNA function. LncRNAs can serve as molecular decoys, scaffolds, super-enhancers, or repressors. These molecules can serve as phenotypic switches for GBM cells at the expression and/or epigenetic levels. LncRNAs can affect stemness/differentiation, proliferation, invasion, survival, DNA damage response, and chromatin dynamics. Aberrant expression of these transcripts may facilitate therapy resistance, leading to tumor recurrence. LncRNAs could serve as novel theragnostic or prognostic biomarkers in GBM and other cancers. RNA-based therapeutics may also be employed to target lncRNAs as a novel route of treatment for primary or recurrent GBM. In this review, we explore the roles of lncRNAs in GBM pathophysiology and posit their novel therapeutic potential for GBM.

miR-143-3p Targets lncRNA PSMG3-AS1 to Inhibit the Proliferation of Hepatocellular Carcinoma Cells

Introduction

The molecular pathogenesis of liver cancer remains unclear; some ncRNAs have been considered as potential drug targets for cancer treatment. LncRNA PSMG3‑AS1 has been reported to promote breast cancer, while its role in hepatocellular carcinoma (HCC) is unknown.

Methods

Bioinformatics analysis was conducted to investigate the relationship between miR-143-3p and PSMG3-AS1. RT-qPCR was used to detect the expression levels of miR-143-3p and PSMG3-AS1 and the correlation between them in HCC. The survival curve was used to analyze the effect of PSMG3-AS1 on the prognosis of liver cancer. RT-qPCR was used to detect the effect of different concentration gradients of miR-143-3p on PSMG3-AS1. CCK8 and clone formation experiments were used to examine the role of miR-143-3p and PSMG3-AS1 in regulating the proliferation of SNU-182 and SNU-398 cells.

Results

Our preliminary bioinformatics analysis showed that miR-143-3p can target PSMG3-AS1. We, therefore, analyzed the interaction between PSMG3-AS1 and miR-143-3p in HCC. We found that PSMG3-AS1 was upregulated, while miR-143-3p was downregulated in HCC. The expression levels of PSMG3‑AS1 and miR-143-3p were closely and inversely correlated with each other. High expression levels of PSMG3‑AS1 predicted poor survival. In HCC cells, overexpression of PSMG3-AS1 led to increased proliferation rates. Overexpression of miR-143-3p played an opposite role and reversed the effect of overexpression of PSMG3‑AS1.

Discussions

miR-143-3p may target PSMG3‑AS1 to inhibit the proliferation of HCC cells.

MiR-449b-5p targets lncRNA PSMG3-AS1 to suppress cancer cell proliferation in lung adenocarcinoma

BACKGROUND

PSMG3-AS1 has been characterized as an oncogenic lncRNA in breast cancer, while its role in other cancers is unknown. This study investigated the role of PSMG3-AS1 in lung adenocarcinoma (LUAD).

METHODS

This study included 64 LUAD patients (42 males and 22 females) who were enrolled between May 2012 and May 2014. RT-qPCR was used to evaluate the expression levels of lncRNA. Cell proliferation analysis was performed using CCK-8 kit.

RESULTS

We found that upregulation of PSMG3-AS1 in LUAD predicted the poor survival of patients. MiR-449b-5p is downregulated in LUAD and the expression levels of LUAD were inversely correlated with the expression levels of PSMG3-AS1. MiR-449b-5p was predicted to target PSMG3-AS1, and overexpression of miR-449b-5p resulted in the downregulation of PSMG3-AS1 in LUAD cells. Cell proliferation analysis showed that overexpression of PSMG3-AS1 resulted in increased rate of cell proliferation. Overexpression of miR-449b-5p reduced the enhancing effects of PSMG3-AS1 on cell proliferation.

CONCLUSIONS

Therefore, miR-449b-5p may target PSMG3-AS1 in LUAD to suppress cancer cell proliferation.