LncRNA OIP5-AS1 Promotes Breast Cancer Progression by Regulating miR-216a-5p/GLO1

LncRNA OIP5-AS1 mediated miR-28-5p provides promising support for the diagnosis and prognosis of cholangiocarcinoma

BACKGROUND

Long non-coding RNAs (lncRNAs) are major research factors in a variety of diseases, and lncRNA OIP5-AS1 (OIP5-AS1) was shown to mediate the progression of various tumors. This paper discusses how OIP5-AS1 could potentially be used for diagnosing and prognosticating cholangiocarcinoma (CHOL).

METHODS

The ENROCI project evaluated the OIP5-AS1 expression in CHOL samples and confirmed it using RT-qPCR. A bioinformatics database predicted the target gene of OIP5-AS1 in CHOL, which was then confirmed by luciferase activity assays. The CCK-8 and Transwell methods were employed to detect the changes in CHOL cell growth and migration levels after OIP5-AS1 knockdown. ROC and Kaplan-Meier curves were plotted to examine the diagnostic and prognostic functions of OIP5-AS1.

RESULTS

In CHOL tissues and cells, OIP5-AS1 was enhanced compared to the controls. Reducing OIP5-AS1 hampered the regulatory capacity of CHOL cells, and miR-28-5p inhibitor repaired this inhibition. Notably, OIP5-AS1 was observed to sponge and downregulate miR-28-5p, exhibiting high sensitivity and specificity (84.4% and 81.3%) in CHOL. G3BP1 was a direct target of miR-28-5p. Decreased OIP5-AS1 level was beneficial for survival (HR = 2.391, P = 0.024).

CONCLUSION

OIP5-AS1 targets and negatively mediates miR-28-5p/G3BP1 axis to promote the activity of CHOL cells, which may be a potential marker for diagnosis and prognosis of CHOL patients.

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.

Rs1347093 regulates microRNA-216/-217 expression and is associated with pancreatic cancer risk

BACKGROUND

Single nucleotide polymorphism (SNP) rs1347093 shows statistically significant association with lung cancer risk, but there is no further rs1347093 expression quantitative trait loci (eQTL) effect information. SNP rs1347093 is located in microRNA-216/-217 (miR-216/-217) locus. In addition, miR-216/-217 have pancreas-enriched expressions. In this study, we examined a potential miR-216/-217 promoter region, and investigated the effect of rs1347093-A allele on the miR-216/-217 promoter activity.

METHODS

Bioinformatics analysis, quantitative real-time PCR, luciferase reporter assay, Western blotting, and cell counting kit-8 (CCK-8) assay were performed.

RESULTS

The miR-216/-217 expressions are down-regulated in pancreatic cancer. In pancreatic cancer patients carrying the rs1347093-A allele, miR-216/-217 expressions were more largely suppressed. We identified a potential promoter region in miR-216/-217 locus and further showed that rs1347093-A allele resulted in significantly reduced promoter activity in pancreatic cancer cells, which could be mediated by MEF2C activities. In terms of mechanism in the pathogenesis of pancreatic cancer, miR-216b-5p expression was down-regulated, thereby preventing it from interacting with beclin-1 mRNA while promoting the survival of pancreatic cancer cells.

CONCLUSIONS

This study may reveal the biological relevance underlying rs1347093-A allele with an increase in pancreatic cancer risk. SNP rs1347093 could be meaningful as a novel biomarker for pancreatic cancer risk.

LncRNA OIP5-AS1 Upregulates the Cyclin D2 Levels to Promote Metastasis of Breast Cancer by Targeting miR-150-5p

OBJECTIVE

Breast cancer (BC) is a cancer that seriously affects women's health. BC cell migration increases the mortality of BC patients. Current studies have shown that long noncoding RNAs (LncRNAs) are related to the metastasis mechanism of BC. This study aimed to explore the function and role of LncRNA OIP5-AS1 in BC. And we analyzed its regulatory mechanism and related modification process.

METHODS

Our study analyzed the expression pattern of OIP5-AS1 in BC tissues and cell lines by qRT-PCR. The effects of OIP5-AS1 on the function of BC cells were detected by CCK-8 and transwell experiments. Bioinformatics analysis and double luciferase reporter gene detection were used to confirm the correlation between OIP5-AS1 and miR-150-5p and between miR-150-5p and Cyclin D2 (CCND2). The rescue test analyzed the effect of miR-150-5p regulating OIP5-AS1. In addition, the N6-methyladenosine (m6A) modification process of OIP5-AS1 was analyzed by RNA m6A dot blot, RIP assay, and double luciferase report experiment.

RESULTS

OIP5-AS1 was significantly upregulated in BC tissues and cell lines. OIP5-AS1 knockdown inhibited BC cell viability, migration and invasion. OIP5-AS1 upregulated CCND2 by binding with miR-150-5p. This process affected the metastasis of BC. Higher degree of m6A methylation was confirmed in BC cell lines. There were some binding sites between methyltransferase like 3 (METTL3) and OIP5-AS1. Moreover, the silencing of METTL3 inhibited the OIP5-AS1 expression through decreasing the m6A methylation levels.

CONCLUSIONS

LncRNA OIP5-AS1 promoted cell viability and metastasis of BC cells by targeting miR-150-5p/CCND2 axis. This process was modified by m6A methylation of METTL3.

N6-methyladenosine modification of linc-OIP5 confers paclitaxel resistance in breast cancer through a DDX5-dependent mechanism

Chemoresistance is a significant obstacle in the treatment of breast cancer (BC). Due to its diverse composition, the causes of chemoresistance in BC are complex and have not been completely understood. In this article, we explored the mechanism of N6-methyladenosine (m6A)-modified long intervening noncoding RNA (linc)-OIP5 in BC chemoresistance. We successfully constructed drug-resistant cell lines MCF-7/P and MDA-MB-231/P by exposing parental MDA-MB-231 and MCF-7 cells to escalating doses of paclitaxel (PTX) and revealed multiple m6A methylation modification sites on linc-OIP5 according to the predictive analysis of the SRAMP database. Linc-OIP5 expression and m6A modification were up-regulated in PTX-resistant BC cells. Inhibition of m6A modification or linc-OIP5 knockdown facilitated PTX-resistant and parental BC cell apoptosis and repressed proliferation and migration. Mechanistically, linc-OIP5 bound to TRIM5 and reduced the ubiquitination of DDX5, thus stabilizing the DDX5 protein. Additionally, DDX5 overexpression partly abrogated the suppressing effects of inhibited m6A modification or si-linc-OIP5 on cell proliferation, migration and PTX resistance. These findings indicate that m6A-modified linc-OIP5 reduced DDX5 ubiquitination and enhanced DDX5 stability by binding to TRIM5, thereby promoting BC cell proliferation, migration and PTX resistance, and inhibiting apoptosis.

OIP5-AS1 enhances the malignant characteristics and resistance to chemotherapy of pancreatic cancer cells by targeting miR-30d-5p/MARCH8

MARCH8, an E3 ubiquitin ligase, plays a crucial role in regulating various cellular processes such as protein degradation and signaling pathways and is implicated in the development and spread of pancreatic cancer. Analysis of pancreatic cancer tissues compared to adjacent normal tissues showed a decrease in miRNA-30d-5p levels and an increase in OIP5-AS1 and MARCH8 levels, as confirmed by qRT-PCR and Western blot analysis. The dual-luciferase reporter assay demonstrated a binding relationship between OIP5-AS1 and miRNA-30d-5p, as well as between miRNA-30d-5p and MARCH8 in PACN-1 cells, derived from a human pancreatic carcinoma specimen. Further investigations utilizing various assays revealed that OIP5-AS1 inhibited apoptosis and promoted cell proliferation, invasion, and migration in PACN-1 cells via the miRNA-30d-5p/MARCH8 axis in vitro. Tumor experiments in nude mice confirmed that OIP5-AS1 enhanced PACN-1 cell growth in vivo through the miRNA-30d-5p/MARCH8 axis. Additionally, OIP5-AS1 was found to activate downstream genes of the JAK-STAT pathway, namely IFNAR2, SOCS3, and JAK1, in PACN-1 cells. Furthermore, OIP5-AS1 increased the IC50 values for doxorubicin, gemcitabine, and cisplatin in PACN-1 cells, as determined by the Cell Counting Kit-8 assay. Overall, OIP5-AS1 was shown to promote aggressive traits and resistance to chemotherapy in PACN-1 cells through the miRNA-30d-5p/MARCH8 axis.

miRNAs as Interconnectors between Obesity and Cancer

Obesity and cancer are a concern of global interest. It is proven that obesity may trigger the development or progression of some types of cancer; however, the connection by non-coding RNAs has not been totally explored. In the present review, we discuss miRNAs and lncRNAs dysregulation involved in obesity and some cancers, shedding light on how these conditions may exacerbate one another through the dysregulation of ncRNAs. lncRNAs have been reported as regulating microRNAs. An in silico investigation of lncRNA and miRNA interplay is presented. Our investigation revealed 44 upregulated and 49 downregulated lncRNAs in obesity and cancer, respectively. miR-375, miR-494-3p, miR-1908, and miR-196 were found interacting with 1, 4, 4 and 4 lncRNAs, respectively, which are involved in PPARγ cell signaling regulation. Additionally, miR-130 was found to be downregulated in obesity and reported as modulating 5 lncRNAs controlling PPARγ cell signaling. Similarly, miR-128-3p and miR-143 were found to be downregulated in obesity and cancer, interacting with 5 and 4 lncRNAs, respectively, associated with MAPK cell signaling modulation. The delicate balance between miRNA and lncRNA expression emerges as a critical determinant in the development of obesity-associated cancers, presenting these molecules as promising biomarkers. However, additional and deeper studies are needed to reach solid conclusions about obesity and cancer connection by ncRNAs.

Integrated analysis and validation of ferroptosis-related genes and immune infiltration in acute myocardial infarction

BACKGROUND

Acute myocardial infarction (AMI) is indeed a significant cause of mortality and morbidity in individuals with coronary heart disease. Ferroptosis, an iron-dependent cell death, is characterized by the accumulation of intracellular lipid peroxides, which is implicated in cardiomyocyte injury. This study aims to identify biomarkers that are indicative of ferroptosis in the context of AMI, and to examine their potential roles in immune infiltration.

METHODS

Firstly, the GSE59867 dataset was used to identify differentially expressed ferroptosis-related genes (DE-FRGs) in AMI. We then performed gene ontology (GO) and functional enrichment analysis on these DE-FRGs. Secondly, we analyzed the GSE76591 dataset and used bioinformatic methods to build ceRNA networks. Thirdly, we identified hub genes in protein-protein interaction (PPI) network. After obtaining the key DE-FRGs through the junction of hub genes with ceRNA and least absolute shrinkage and selection operator (LASSO). ImmucellAI was applied to estimate the immune cell infiltration in each sample and examine the relationship between key DE-FRGs and 24 immunocyte subsets. The diagnostic performance of these genes was further evaluated using the receiver operating characteristic (ROC) curve analysis. Ultimately, we identified an immune-related ceRNA regulatory axis linked to ferroptosis in AMI.

RESULTS

Among 56 DE-FRGs identified in AMI, 41 of them were integrated into the construction of competitive endogenous RNA (ceRNA) networks. TLR4 and PIK3CA were identified as key DE-FRGs and PIK3CA was confirmed as a diagnostic biomarker for AMI. Moreover, CD4_native cells, nTreg cells, Th2 cells, Th17 cells, central-memory cells, effector-memory cells, and CD8_T cells had higher infiltrates in AMI samples compared to control samples. In contrast, exhausted cells, iTreg cells, and Tfh cells had lower infiltrates in AMI samples. Spearman analysis confirmed the correlation between 24 immune cells and PIK3CA/TLR4. Ultimately, we constructed an immune-related regulatory axis involving XIST and OIP5-AS1/miR-216a/PIK3CA.

CONCLUSION

Our comprehensive analysis has identified PIK3CA as a robust and promising biomarker for this condition. Moreover, we have also identified an immune-related regulatory axis involving XIST and OIP5-AS1/miR-216a/PIK3CA, which may play a key role in regulating ferroptosis during AMI progression.

LncRNA OIP5-AS1/miR-410-3p/Wnt7b axis promotes the proliferation of rheumatoid arthritis fibroblast-like synoviocytes via regulating the Wnt/β-catenin pathway

LncRNA OIP5-AS1 has a common gene imbalance in various cancers and tumours, which plays an important role in regulating its biological function. However, there are few studies on lncRNA OIP5-AS1 in rheumatoid arthritis (RA). The purpose of the present study was to investigate the role of lncRNA OIP5-AS1 in the pathogenesis of RA. In the present study, we established an adjuvant arthritis (AA) rat model to obtain primary fibroblast-like synoviocytes (FLSs);The subcellular localisation of lncRNA OIP5-AS1 was detected by fluorescence in situ hybridisation (FISH) assay; Cell proliferation of FLSs was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay;IL-1β, IL-6 and TNF-α concentrations were measured by enzyme-linked immunosorbent assay (ELISA);Quantitative real-time PCR (qRT-PCR), Western blots(WB) and immunofluorescence were used to detect the expression of lncRNA OIP5-AS1/miR-410-3p/wnt7b signal axis and Wnt/β-catenin signal pathway related indicators in FLSs. FISH assay confirmed the presence of lncRNA OIP5-AS1 in the cytoplasm, suggesting that it acts as a competing endogenous RNA (ceRNA). qRT-PCR showed that the expression of lncRNA OIP5-AS1 was upregulated in FLSs, while the expression of miR-410-3p was downregulated in FLSs. We also found that lncRNA OIP5-AS1 knockdown inhibited the proliferation and inflammation of FLSs. Moreover, the expression of Wnt7b, the downstream target gene of miR-410-3p, and the activation of the Wnt/β-catenin signalling pathway were also inhibited by lncRNA OIP5-AS1 knockdown. These results suggested that lncRNA OIP5-AS1 promotes the activation of the Wnt/β-catenin signalling pathway by regulating the miR-410-3p/Wnt7b signalling axis, thereby participating in the occurrence and development of RA.

circPLOD2 knockdown suppresses endometriosis progression via the miR-216a-5p/ZEB1 axis

The present study aimed to identify the role of circPLOD2 in endometriosis and its underlying mechanisms. We determined circPLOD2 and miR-216a-5p expression in ectopic endometrial (EC) and eutopic endometrial (EU) samples as well as in endometrial samples from uterine fibroids of ectopic patients (EN) and embryonic stem cells (ESCs) using qRT-PCR. The association between circPLOD2 and miR-216a-5p or miR-216a-5p and zinc finger E-box binding homeobox 1 (ZEB1) expression was analyzed using Starbase, TargetScan, and dual-luciferase reporter gene assays. Cell viability, apoptosis, and migration and invasion were assessed using MTT, flow cytometry, and transwell assays, respectively. In addition, qRT-PCR and western blotting was used to measure circPLOD2, miR-216a-5p, E-cadherin, N-cadherin, and ZEB1 expression. circPLOD2 was upregulated and miR-216a-5p was downregulated in EC samples compared with that in EU samples. Similar trends were observed in ESCs. circPLOD2 interacted and negatively regulated miR-216a-5p expression in EC-ESCs. circPLOD2-siRNA significantly inhibited EC-ESC growth; promoted cellular apoptosis; and inhibited EC-ESC migration, invasion, and epithelial-mesenchymal transition; these effects could be reversed following miR-216a-5p inhibitor transfection. miR-216a-5p directly targeted and negatively regulated ZEB1 expression in EC-ESCs. In conclusion, circPLOD2 promotes the proliferation, migration, and invasion of EC-ESCs and inhibits their apoptosis by targeting miR-216a-5p. These findings indicate potential therapeutic targets for endometriosis.

Roles and Mechanisms of Long Non-Coding RNAs in Breast Cancer

Breast cancer is a major health threat and the second leading cause of cancer-related deaths in women worldwide. The detailed mechanisms involved in the initiation and progression of breast cancer remain unclear. In recent years, amounting evidence indicated that long non-coding RNAs (lncRNAs) played crucial roles in regulating various biological processes and malignancy tumors, including breast cancer. In this review, we briefly introduce the functions and underlying mechanisms by which lncRNAs are involved in breast cancer. We summarize the roles of the lncRNAs in regulating malignant behaviors of breast cancer, such as cell proliferation, migration and invasion, epithelial-mesenchymal transition (EMT), apoptosis, and drug resistance. Additionally, we also briefly summarize the roles of circular RNAs (circRNAs) in breast cancer carcinogenesis.

LINC01140 Targeting miR-452-5p/RGS2 Pathway to Attenuate Breast Cancer Tumorigenesis

Background

LINC01140 has been known to be involved in various cancers. However, its underlying molecular mechanism in breast cancer (BC) needs further exploration.

Methods

The LINC01140, miR-452-5p, and RGS2 levels in BC cells and tissues were evaluated by means of RT-qPCR and western blotting. The variations in the biological functions of BC cells were analyzed through CCK-8, transwell, western blotting, and xenograft experiments to observe cell viability, migration, levels of apoptosis-related proteins (Bax and Bcl-2), and tumor growth. The correlations existing among LINC01140, miR-452-5p, and RGS2 were validated through luciferase reporter and RIP assays.

Results

LINC01140 and RGS2 were remarkably downregulated in BC cells and tissues, whereas miR-452-5p was upregulated. LINC01140 overexpression diminished BC cell viability, migration, and tumor growth and facilitated apoptosis. MiR-452-5p upregulation enhanced cell viability and migration and suppressed apoptosis. Nevertheless, the additional upregulation of LINC01140 could reverse the promotive effects of miR-452-5p upregulation. Additionally, RGS2 overexpression inhibited the malignant phenotypes of BC cells, but miR-452-5p upregulation abolished this effect. In terms of mechanisms, LINC01140 acted as a miR-452-5p sponge. Moreover, RGS2 was determined to be miR-452-5p's downstream target gene in BC.

Conclusion

LINC01140 functioned as an antitumor agent in BC by sponging miR-452-5p to release RGS2. This hints that LINC01140 is a promising therapeutic target for BC.

LncRNA OR2A1-AS1 index predicts survival in germinal center-like diffuse large B-cell lymphoma

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is a highly aggressive form of non-Hodgkin lymphoma. Long noncoding RNA (lncRNA) has been evaluated as prognostic markers in various carcinomas. However, the prognostic value of the lncRNA index in DLBCL has not been fully understood. Hence, this study aimed to identify the prognostic value of lncRNA olfactory receptor family 2 subfamily A member 1-antisense RNA 1 (OR2A1-AS1) in DLBCL.

METHODS

The Gene Expression Omnibus (GEO) database was used to obtain the GSE97336 dataset comprising lncRNA expression profiles. Quantitative reverse transcription polymerase chain reaction (QRT-PCR) was conducted to evaluate the expression of OR2A1-AS1 in 98 cases of DLBCL.

RESULTS

OR2A1-AS1 expression was considerably reduced in DLBCL patients, reduced OR2A1-AS1 expression was linked to a shorter overall survival (OS) and progression-free survival (PFS) in DLBCL patients, especially those with the germinal center B-cell-like subtype (GCB). Multivariate analysis (MVA) revealed that the OR2A1-AS1 index had prognostic significance. Patients with low OR2A1-AS1 expression have a poor prognosis.

CONCLUSIONS

OR2A1-AS may represent an effective predictor of patients' outcomes with DLBCL.

Long non-coding RNAs (lncRNAs); roles in tumorigenesis and potentials as biomarkers in cancer diagnosis

New research has indicated that long non-coding RNAs (lncRNAs) play critical roles in a broad range of biological processes, including the pathogenesis of many complex human diseases, including cancer. The detailed regulation mechanisms of many lncRNAs in cancer initiation and progression have yet to be discovered, even though a few of lncRNAs' functions in cancer have been characterized. In the present study, we summarize recent advances in the mechanisms and functions of lncRNAs in cancer. We focused on the roles of newly-identified lncRNAs as oncogenes and tumor suppressors, as well as the potential pathways these molecules could play. The paper also discusses their potential uses as biomarkers for the diagnosis and prognosis of cancer.

LncRNA OIP5-AS1 Knockdown Facilitated the Ferroptosis and Immune Evasion by Modulating the GPX4 in Oesophageal Carcinoma

Objective

Oesophageal cancer (EC) is an extremely invasive malignancy, which has bad prognosis that requires safe and effective treatment modalities. Immunotherapy has provided new ideas for the treatment of EC in recent years. This project was conducted to probe into the role and mechanism of lncRNA OIP5-AS1 in ferroptosis and immunotherapy of EC.

Methods

Cell viability and multiplication were assessed through CCK-8, colony formation assays. Levels of Fe²⁺, MDA, and lipid ROS were applied to determine ferroptosis. GPX4 and OIP5-AS1 levels were examined through real-time PCR assay. The relationship between OIP5-AS1 and GPX4 was estimated through RNA immunoprecipitation assay. Flow cytometry was applied to examine the effect of OIP5-AS1 on CD8+ T cells.

Results

OIP5-AS1 inhibition significantly inhibited EC cell viability and proliferation, induced ferroptosis, and downregulated GPX4 levels, while GPX4 reversed these effects. OIP5-AS1/GPX4 induced CD8+ T cell interaction and induced apoptosis through PD-1/PD-L1 immune checkpoints of CD8+ T cells.

Conclusion

OIP5-AS1/GPX4 promotes EC development and relieved ferroptosis; furthermore, OIP5-AS1/GPX4 facilitated immune evasion via modulation of PD-1/PD-L1, suggesting aiming at OIP5-AS1 is a possible route which might enhance the effectiveness of immunotherapy.

Long non-coding RNA H19X promotes tumorigenesis and metastasis of colorectal cancer through regulating the miR-503-5p/KANK1 axis

BACKGROUND

It has been well established that the long non-coding RNAs (lncRNAs) plays a critical role in tumor progression. However, the function of these transcripts and mechanisms responsible for their deregulation in colorectal cancer (CRC) remain to be investigated.

OBJECTIVE

To explore the potential effect and regulation mechanism of lncRNA H19X in colorectal cancer.

METHODS

We predicted and validated long non-coding RNA H19X from microarray data of colorectal cancer tissues. In addition, the biological behaviors of H19X and miR-503-5p on CRC were examined in vitro and in vivo, including MTT, colony formation assay, Hoechst33342 and transwell assay. The mRNA and protein levels of KN Motif and Ankyrin Repeat Domains 1 (KANK1) were analyzed by Quantitative real-time PCR (qRT-PCR), western blotting (WB) assay. Moreover, bioinformatics tools and dual-luciferase reporter assay were applied to demonstrate the relationship between KANK1 and miR-503-5p.

RESULTS

H19X was remarkably up-regulated in CRC tissues. Its expression related to tumor size (p = 0.041), lymph node metastasis (p = 0.037), distal metastasis (p = 0.028), advanced TNM stage (p = 0.034) and poor survival in CRC. H19X acted as an oncogenic lncRNA that induced CRC cell proliferation, invasion and metastasis. Through a number of functional studies, we found that H19X silencing inhibited the malignance phenotype of cancer cells through loss of miR-503-5p. Further studies demonstrated that miR-503-5p was involved in the progression of CRC by directly regulating the downstream target KANK1.

CONCLUSION

Collectively, the findings of the present study indicate H19X/miR-503-5p/KANK1 axis has critical role in the progression of colorectal cancer, providing an effective prognostic indicator and promising target in treatment of colorectal cancer.

The role of lncRNA OIP5-AS1 in cancer development and progression

OIP5-AS1, a conserved lncRNA, has been reported to be involved in several biological and pathological processes, including oncogenesis. OIP5-AS1 exerts its oncogenic or antitumor functions via regulation of different miRNAs in various cancer types. In this review, we describe the dysregulation of OIP5-AS1 expression in a variety of human cancers. Moreover, we discuss the multiple functions of OIP5-AS1 in cancer, including in proliferation, apoptosis, autophagy, ferroptosis, cell cycle, migration, metastasis, invasion, epithelial to mesenchymal transition, angiogenesis, cancer stem cells and drug resistance. Furthermore, we provide a future perspective for OIP5-AS1 research. We conclude that targeting OIP5-AS1 might be a promising cancer therapy approach.

A Three-mRNA Signature Associated with Pyrimidine Metabolism for Prognosis of BRCA

Objective

Breast invasive carcinoma (BRCA), as a systemic disease, is currently the most malignant tumor among women. Early detection of BRCA will increase the probability of cure. Pyrimidine metabolism (PyM) stands for an essential metabolic pathway related to DNA replication of cancer cells, which may also serve as a diagnostic marker and therapeutic target. Therefore, the aim of this research is to discover a prognostic signature associated with PyM for BRCA.

Methods

The BRCA mRNA sequencing data along with microarray data were obtained based on The Cancer Genome Atlas (TCGA) database. In addition, 4 PyM-related gene sets were profiled through gene set enrichment analysis (GSEA); it revealed the core genes differentially expressed in cancer and paracancerous tissue. Thereafter, genes were subjected to univariate as well as multivariate regression for constructing an mRNA signature to independently predict BRCA prognosis. Then, the Kaplan-Meier (KM) curve was applied for validation. The prognostic power of the signature was verified against the METABRIC (Molecular Taxonomy of Breast Cancer International Consortium) database.

Results

We constructed a three-mRNA (RRM2B, NME3, and POLD2) gene signature related to PyM to predict overall survival (OS) for BRCA. The as-constructed gene signature was adopted to classify cases as high- or low-risk group, identifying patients with BRCA with poor prognosis. Additionally, the risk score obtained using our constructed 3-mRNA prognosis signature is independent from other clinical variables.

Conclusion

Our findings suggested that PyM-related mRNA signature might be a combined prognostic biomarker for BRCA and can provide important reference that are useful for individualized treatment for BRCA patients.

Long non-coding RNA OIP5-AS1 (Cyrano): A context-specific regulator of normal and disease processes

Long non-coding (lnc) RNAs have been implicated in a plethora of normal biological functions, and have also emerged as key molecules in various disease processes. OIP5-AS1, also commonly known by the alias Cyrano, is a lncRNA that displays broad expression across multiple tissues, with significant enrichment in particular contexts including within the nervous system and skeletal muscle. Thus far, this multifaceted lncRNA has been found to have regulatory functions in normal cellular processes including cell proliferation and survival, as well as in the development and progression of a myriad disease states. These widespread effects on normal and disease states have been found to be mediated through context-specific intermolecular interactions with dozens of miRNAs and proteins identified to date. This review explores recent studies to highlight OIP5-AS1's contextual yet pleiotropic roles in normal homeostatic functions as well as disease oetiology and progression, which may influence its utility in the generation of future theranostics.

Cancer-associated fibroblasts-derived exosomes promote lung cancer progression by OIP5-AS1/ miR-142-5p/ PD-L1 axis

Cancer-associated fibroblasts (CAFs) are the most important stromal cells in the tumor microenvironment (TEM) and have been reported to regulate various cancer development. Exosomes are considered important elements involved in intercellular communication and TME regulation, while the potential function of CAFs in lung cancer immunosuppressive microenvironments remains unknown. CAFs-derived exosomes (CAFs-exo) and normal fibroblasts (NFs)-derived exosomes (NFs-exo) were isolated by ultra-centrifugation and characterized by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and western blot analysis. A549 cells were co-cultured with peripheral blood mononuclear cells (PBMCs). Flow cytometry assay was performed to detect the killing role of PBMCs on A549 cells. Bioinformatics and luciferase reporter assays were used to analyze the relationship among microRNA (miRNA), long non-coding RNA (lncRNA) and target gene. BALB/c mice were used to construct the lung cancer model by subcutaneous injection. Programmed death ligand 1 (PD-L1) was up-regulated in lung cancer tissues and cells. PD-L1 also up-regulated in CAFs cell medium-mediated A549 cells. CAFs decreased PBMCs induced-cell apoptosis through increasing PD-L1 in A549 cells. Moreover, CAFs transferred exosomes to lung cancer cells to suppress the killing effect of PBMCs through up-regulating PD-L1. Using microarray assays, opa-interacting protein 5 antisense RNA 1 (OIP5-AS1) level was highly expressed in CAFs-exos. After treatment by CAFs-exos, miR-142-5p level was significantly down-regulated in A549 cells. OIP5-AS1 served as a sponge to target miR-142-5p and negatively regulated miR-142-5p expression in lung cancer cells. In addition, PD-L1 was a direct target of miR-142-5p. CAFs derived exosomal OIP5-AS1 reduced PBMCs induced-cell apoptosis and promoted tumor growth through decreasing miR-142-5p and up-regulating PD-L1. CAFs-derived exosomes suppressed the role of PBMCs induced-killing of lung cancer cells and promoted lung cancer progression by OIP5-AS1/ miR-142-5p/ PD-L1 axis, which provided a potential opportunity for diagnosis and treatment of lung cancer.

Identification and Roles of miR-29b-1-3p and miR29a-3p-Regulated and Non-Regulated lncRNAs in Endocrine-Sensitive and Resistant Breast Cancer Cells

Despite improvements in the treatment of endocrine-resistant metastatic disease using combination therapies in patients with estrogen receptor α (ERα) primary tumors, the mechanisms underlying endocrine resistance remain to be elucidated. Non-coding RNAs (ncRNAs), including microRNAs (miRNA) and long non-coding RNAs (lncRNA), are targets and regulators of cell signaling pathways and their exosomal transport may contribute to metastasis. Previous studies have shown that a low expression of miR-29a-3p and miR-29b-3p is associated with lower overall breast cancer survival before 150 mos. Transient, modest overexpression of miR-29b1-3p or miR-29a-3p inhibited MCF-7 tamoxifen-sensitive and LCC9 tamoxifen-resistant cell proliferation. Here, we identify miR-29b-1/a-regulated and non-regulated differentially expressed lncRNAs in MCF-7 and LCC9 cells using next-generation RNA seq. More lncRNAs were miR-29b-1/a-regulated in LCC9 cells than in MCF-7 cells, including DANCR, GAS5, DSCAM-AS1, SNHG5, and CRND. We examined the roles of miR-29-regulated and differentially expressed lncRNAs in endocrine-resistant breast cancer, including putative and proven targets and expression patterns in survival analysis using the KM Plotter and TCGA databases. This study provides new insights into lncRNAs in endocrine-resistant breast cancer.

UCA1 Overexpression Promotes Hypoxic Breast Cancer Cell Proliferation and Inhibits Apoptosis via HIF-1α Activation

The noncoding RNA termed urothelial carcinoma-associated 1 (UCA1) is an oncogenic lncRNA involved in promoting the growth of several tumors through various pathways. The aim of this study was to explore the expression of UCA1 in hypoxic breast cancer and its impact on tumorigenesis in low levels of oxygen. Here, we show that UCA1 is upregulated in a number of hypoxic (1% O₂) breast cancer cells. In addition, UCA1 expression is significantly overexpressed in breast cancer tissues compared to matched normal cells. UCA1 knockdown in hypoxia inhibits breast cancer proliferation and induces apoptosis. The knockdown of hypoxia-inducible transcription factor 1α (HIF-1α) but not HIF-2α significantly decreases the expression of UCA1 in hypoxia. Overall, these findings indicate that UCA1 is a hallmark of hypoxic breast cancer and its expression is positively regulated by HIF-1α.

A review on the role of oncogenic lncRNA OIP5-AS1 in human malignancies

OIP5-AS1 is a long non-coding transcript with high expression in nervous system, but crucial functions in the neoplastic transformation. This lncRNA partake in the regulation of cell cycle transition at different points. Moreover, it acts a competing endogenous RNA for tens of microRNAs among them are miR-338-3p, miR-204-5p, miR-641, miR-422a, miR-367-3p, miR-153-3p, miR-186, miR-369-3p, miR-137, miR-342-3p, miR‑429, miR-3163, miR-363-3p, miR-186a-5p, hsa-miR-26a-3p, miR‑300, miR-217, miR-378a-3p and miR-448. OIP5-AS1 influence the carcinogenesis via different routes among them is modulation of epithelial-mesenchymal transition. Expression of OIP5-AS1 has been elevated in nearly all kinds of neoplastic tissues except for multiple myeloma. Moreover, in bladder, gastric cancer and lung cancers, assessment of its expression in clinical samples has led to conflicting results. In the current paper, we have provided a comprehensive collection of research papers that evaluated function of OIP5-AS1 in diverse cancer types.