The role of lncRNAs in the development of endometrial carcinoma

microRNA 21 and long non-coding RNAs interplays underlie cancer pathophysiology: A narrative review

Non-coding RNAs (ncRNAs) are a diverse group of functional RNA molecules that lack the ability to code for proteins. Despite missing this traditional role, ncRNAs have emerged as crucial regulators of various biological processes and have been implicated in the development and progression of many diseases, including cancer. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are two prominent classes of ncRNAs that have emerged as key players in cancer pathophysiology. In particular, miR-21 has been reported to exhibit oncogenic roles in various forms of human cancer, including prostate, breast, lung, and colorectal cancer. In this context, miR-21 overexpression is closely associated with tumor proliferation, growth, invasion, angiogenesis, and chemoresistance, whereas miR-21 inactivation is linked to the regression of most tumor-related processes. Accordingly, miR-21 is a crucial modulator of various canonical oncogenic pathways such as PTEN/PI3K/Akt, Wnt/β-catenin, STAT, p53, MMP2, and MMP9. Moreover, interplays between lncRNA and miRNA further complicate the regulatory mechanisms underlying tumor development and progression. In this regard, several lncRNAs have been found to interact with miR-21 and, by functioning as competitive endogenous RNAs (ceRNAs) or miRNA sponges, can modulate cancer tumorigenesis. This work presents and discusses recent findings highlighting the roles and pathophysiological implications of the miR-21-lncRNA regulatory axis in cancer occurrence, development, and progression. The data collected indicate that specific lncRNAs, such as MEG3, CASC2, and GAS5, are strongly associated with miR-21 in various types of cancer, including gastric, cervical, lung, and glioma. Indeed, these lncRNAs are well-known tumor suppressors and are commonly downregulated in different types of tumors. Conversely, by modulating various mechanisms and oncogenic signaling pathways, their overexpression has been linked with preventing tumor formation and development. This review highlights the significance of these regulatory pathways in cancer and their potential for use in cancer therapy as diagnostic and prognostic markers.

Estrogen promotes the proliferation and migration of endometrial cancer cells by upregulating the expression of lncRNA HOTAIR

OBJECTIVE

Estrogen (E2) is the main contributor to the progression of endometrial cancer (EC). The long noncoding RNA HOX antisense intergenic RNA (HOTAIR) is emerging as a new regulator in several cancer types. This study aimed to investigate the role of HOTAIR in EC development and identify the underlying molecular mechanisms.

METHODS

HOTAIR expression levels in human EC tissues and the corresponding adjacent tissues and human EC Ishikawa cells were determined by quantitative PCR. Ishikawa cells were treated with E2 or estrogen receptor (ER) inhibitor ICI182780, transfected with siHOTAIR oligo, or infected with lentivirus expressing shHOTAIR/shNC, alone or in combinations. The protein expression of polycomb repressive complex 2 (PRC2) was evaluated by western blotting, and cell migration was measured by transwell assays. A xenograft tumorigenic model was established by inoculating control or stable shHOTAIR-infected Ishikawa cells into nude mice and implanting 17β-estradiol release pellets.

RESULTS

HOTAIR expression was significantly elevated in human EC tissues. E2 exposure markedly increased HOTAIR levels in Ishikawa cells. Notably, E2 increased the protein expression of PRC2 and promoted EC cell migration, which were dependent on HOTAIR expression, as HOTAIR knockdown abolished these effects of E2. Similarly, E2 promoted the in vivo proliferation of grafted Ishikawa cells via upregulated HOTAIR expression in nude mice.

CONCLUSIONS

Human EC tissues highly express HOTAIR, and E2-induced EC progression depends on HOTAIR expression. This work suggests that the E2-HOTAIR axis is a potential therapeutic target in EC therapy.

LncRNAs signatures associated with cuproptosis predict the prognosis of endometrial cancer

Background: Endometrial cancer (UCEC) is the sixth most common cancer in women, and although surgery can provide a good prognosis for early-stage patients, the 5-year overall survival rate for women with metastatic disease is as low as 16%. Long non-coding RNAs (LncRNAs) are thought to play an important role in tumor progression. Cuproptosis is a recently discovered form of cell death in which copper binds directly to the lipoacylated component of the tricarboxylic acid (TCA) cycle. The aggregation of these copper-bound listed mitochondrial proteins and the loss of Fe-S cluster proteins trigger proteotoxic stress, which leads to cell death. Therefore, the aim of this work was to investigate the role of Cuproptosis-related LncRNAs signaling in clinical prognostic prediction and immunotherapy, as well as the relationship between tumor mutation burden. Methods: Genomic, clinical and mutational data of endometrial cancer patients were presented in the TCGA database, and cuproptosis-related genes obtained from related studies. Coexpression analysis and Cox regression analysis were used to construct prognostic features. Patients were divided into high risk group and low risk group, and then ROC, survival rate, risk curve, principal component analysis, independent prognostic analysis and clinical subgroup model validation were performed to observe the prognostic value of characteristics. Subsequently, the GO and genomic KEGG enrichment and immune-related functions of LncRNAs as well as the tumor mutation burden were analyzed. Results: In 548 UCEC case data, we identified five associated LncRNAs co-expressed with cuproptosis genes, and we found that high-risk patients had poorer overall survival (OS), progression-free survival (PFS), and higher mortality. Independent prognostic analysis, ROC showed that the LncRNAs associated with cuproptosis could accurately predict the prognosis of patients. Enrichment analysis revealed that the biological functions of LncRNAs were related to tumorigenesis. We also discovered suppression of immune-related functions in high-risk patients with oncogene mutations, higher tumor mutation burden in low-risk patients, and longer overall survival in patients with higher tumor mutation burden. Conclusion: The identification of five LncRNAs associated with cuproptosis can accurately predict the prognosis of patients with endometrial cancer, and may provide a new perspective for clinical application and immunotherapy.

Pan-Cancer Gene Analysis of m6A Modification and Immune Infiltration in Uterine Corpus Endometrial Carcinoma

Objective

This investigation was to test the potential role of m6A-related long non-coding RNAs (lncRNAs) and immune infiltration as crucial factors in the diagnosis and treatment of uterine corpus endometrial cancer (UCEC).

Method

The UCEC RNA-seq data were downloaded in the Cancer Genome Atlas (TCGA, https://portal.gdc.cancer.gov/). There were 587 samples totally, containing 543 UCEC cases and 35 healthy cases. The clinical information of UCEC cases included survival time, survival status, gender, age, stage, and TMN stage. Twenty-three m6A-related genes were found in published journals. The RNA-seq documents of UCEC were downloaded in the Cancer Genome Atlas (TCGA). The hub gene data of UCEC were downloaded from GEPIA2 database. The different packages of R language were applied to calculate and analyze in this research.

Results

Among 587 cases in our study, we discovered 3039 lncRNAs in the TCGA-UCEC database. After the differential analysis, 23 m6A-associated genetics were screened and twenty-one m6A-associated differential genetics were found. In the end, we obtained 20 m6A-related lncRNAs. LNCTAM34A was considered as a predictive gene through univariate and multivariate Cox regression analysis. In addition to the above, patients with high LNCTAM34A expression had better outcomes than those with low LNCTAM34A expression. The high-risk cohort had greater scores of activated dendritic cells (aDCs), B cells, and T cell regulatory (Tregs) than low-risk cohort; in the meanwhile, high-risk cohort had lower scores of DCs and iDCs. Then, the high-risk cohort displayed greater scores in the immune functions of MHC class I, para-inflammation, and type I IFN response than those of low-risk cohort. Among 27 immune-inducible genes, the level of CD244, KIR3DLI, NRP1, PDCD1LG2, and TNFRSF8 was reduced in UCEC samples and the level of CD27, CD28, CD70, CD80, CD86, HAVCR2, ICOS, IDO1, LAIR1, PDCD1, TIGIT, TNFRSF18, -25, -9, -14, and VTCN1 was increased in UCEC samples.

Conclusion

The key role of M6A-related lncRNAs in immune microenvironment in high-risk patients of UCEC. The patients with strong expression of LNCTAM34A have a good prognosis, and LNCTAM34A can be used as a prognostic gene for UCEC. m6A-related lncRNAs can be used as a potential treatment for UCEC. Our observations can be used as a hypothetical basis for future in vitro and animal experiments.

Identification of Five m6A-Related lncRNA Genes as Prognostic Markers for Endometrial Cancer Based on TCGA Database

Background. Due to difficulties involved in its early diagnosis and adequate prognostication, uterine corpus endometrial carcinoma (UCEC) is one of the most serious threats to human health, with the five-year survival rate being as low as roughly 60%. The discovery of specific biomarkers that serve as prognosticators of UCEC is of great significance. The role of N6-methyladenosine- (m6A-) related long noncoding RNAs (lncRNAs) in the pathogenesis of UCEC remains undefined. In this study, we explored the expression profiles of m6A-related lncRNAs of patients with UCEC and identified novel prognostic markers for UCEC. Methods. Gene expression and clinical data were extracted from The Cancer Genome Atlas. Coexpression analysis was performed to identify m6A-related lncRNAs, which were entered into univariate Cox regression models for evaluating the prognosis of UCEC. Clusters of UCEC patients and enrichment pathways were identified using consistent data clustering and gene set enrichment analysis (GSEA). A risk score model was established, and Kaplan–Meier analysis was conducted for investigating overall survival (OS) across two patient groups (high risk and low risk). Lastly, the relationship between the risk score and the cell content of 22 types of immune cells, clusters, age, programmed cell death 1 ligand-1 (PD-L1) expression level, immune score, and pathological grade was analyzed. Results. We identified a total of 2084 lncRNAs associated with m6A, of which 32 lncRNAs were prognostically relevant. Two clusters (clusters 1 and 2) of patients with UCEC were defined; patients in cluster 1 were found to have significantly higher pathological grades and shorter overall survival time compared to those in cluster 2. GSEA showed that “MITOTIC SPINDLE and other pathways” were more enriched in cluster 1. Five major lncRNAs associated with m6A were screened out, and risk score modeling was used for UCEC prognosis prediction. High risk scores were associated with a shorter OS. The risk score was also verified as an independent prognostic indicator for UCEC and was related to immune cell infiltration levels. Finally, we observed a higher pathological grade and greater levels of PD-L1 in the high-risk group than in the low-risk group of patients. Conclusions. m6A-related lncRNAs play an important role in UCEC progression. The risk-based model constructed from the five key m6A-related lncRNAs was implicated in immune cell infiltration and can potentially be an accurate prognosticator for UCEC.

Analysis of lncRNA sequences: FAM3D-AS1, LINC01230, LINC01315 and LINC01468 in endometrial cancer

Background

The analysis of long non-coding RNA (lncRNA) in endometrial cancer is a novel field of science. Although numerous lncRNA sequences have been identified until today, their correlation with endometrial cancer is still undetermined. The aim of this study was to analyze the expression of four lncRNA sequences: FAM3D-AS1, LINC01230, LINC01315 and LINC01468 and to investigate their significance in endometrial cancer.

Methods

LncRNA sequences were investigated in paraffin blocks (tumor tissue and non-malignant endometrial tissue in archival postoperative specimens) in endometrial cancer patients (Cases, n = 120) and in cancer-free controls (n = 80) using real-time PCR assay.

Results

This study revealed a lower expression of LINC01468 in endometrial cancer patients than in controls. Both LINC01468 and FAM3D-AS1 were positively correlated with Body Mass Index (BMI) in cancer-free controls.

Conclusions

LncRNA LINC01468 may be a protective factor in development of endometrial cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09426-2.

ABHD11-AS1: An Emerging Long Non-Coding RNA (lncRNA) with Clinical Significance in Human Malignancies

The aberrant expression of lncRNAs has been linked to the development and progression of different cancers. One such lncRNA is ABHD11 antisense RNA 1 (ABHD11-AS1), which has recently gained attention for its significant role in human malignancies. ABHD11-AS1 is highly expressed in gastric, lung, breast, colorectal, thyroid, pancreas, ovary, endometrium, cervix, and bladder cancers. Several reports highlighted the clinical significance of ABHD11-AS1 in prognosis, diagnosis, prediction of cancer progression stage, and treatment response. Significantly, the levels of ABHD11-AS1 in gastric juice had been exhibited as a clinical biomarker for the assessment of gastric cancer, while its serum levels have prognostic potential in thyroid cancers. The ABHD11-AS1 has been reported to exert oncogenic effects by sponging different microRNAs (miRNAs), altering signaling pathways such as PI3K/Akt, epigenetic mechanisms, and N6-methyladenosine (m⁶A) RNA modification. In contrast, the mouse homolog of AHD11-AS1 (Abhd11os) overexpression had exhibited neuroprotective effects against mutant huntingtin-induced toxicity. Considering the emerging research reports, the authors attempted in this first review on ABHD11-AS1 to summarize and highlight its oncogenic potential and clinical significance in different human cancers. Lastly, we underlined the necessity for future mechanistic studies to unravel the role of ABHD11-AS1 in tumor development, prognosis, progression, and targeted therapeutic approaches.

Long Noncoding RNA Mediated Regulation in Human Embryogenesis, Pluripotency, and Reproduction

Long noncoding RNAs (lncRNAs), a class of noncoding RNAs with more than 200 bp in length, are produced by pervasive transcription in mammalian genomes and regulate gene expression through various action mechanisms. Accumulating data indicate that lncRNAs mediate essential biological functions in human development, including early embryogenesis, induction of pluripotency, and germ cell development. Comprehensive analysis of sequencing data highlights that lncRNAs are expressed in a stage-specific and human/primate-specific pattern during early human development. They contribute to cell fate determination through interacting with almost all classes of cellular biomolecules, including proteins, DNA, mRNAs, and microRNAs. Furthermore, the expression of a few of lncRNAs is highly associated with the pathogenesis and progression of many reproductive diseases, suggesting that they could serve as candidate biomarkers for diagnosis or novel targets for treatment. Here, we review research on lncRNAs and their roles in embryogenesis, pluripotency, and reproduction. We aim to identify the underlying molecular mechanisms essential for human development and provide novel insight into the causes and treatments of human reproductive diseases.

Long noncoding RNA SNHG25 promotes the malignancy of endometrial cancer by sponging microRNA-497-5p and increasing FASN expression

BACKGROUND

Small nucleolar RNA host gene 25 (SNHG25), a long noncoding RNA, has been well-studied in epithelial ovarian cancer. However, the specific functions of SNHG25 in endometrial cancer (EC) have not been studied yet. In this study, we aimed to elucidate the clinical significance of SNHG25 in EC and determine the regulatory activity of SNHG25 on the tumor-associated EC phenotype. We also thoroughly explored the molecular mechanisms underlying SNHG25 function in EC.

METHODS

Gene expression was measured using quantitative real-time polymerase chain reaction. The detailed functions of SNHG25 in EC were examined by performing loss-of-function experiments. Moreover, the regulatory mechanisms involving SNHG25, microRNA-497-5p, and fatty acid synthase (FASN) were unveiled using the luciferase reporter assay and RNA immunoprecipitation.

RESULTS

We observed a high level of SNHG25 in EC using the TCGA dataset and our study cohort. Patients with a high SNHG25 level had shorter overall survival than those with a low SNHG25 level. SNHG25 deficiency resulted in tumor-repressing activities in EC cells by decreasing cell proliferation, migration, and invasion and promoting cell apoptosis. Furthermore, the function of SNHG25 depletion in impairing tumor growth in vivo was confirmed. SNHG25 sequestered miR-497-5p as a competing endogenous RNA in EC and consequently positively regulated FASN expression. Thus, the decrease in miR-497-5p or increase in FASN could neutralize the modulatory actions of SNHG25 knockdown in EC cells.

CONCLUSIONS

The depletion of SNHG25 impedes the oncogenicity of EC by targeting the miR-497-5p/FASN axis. The newly elucidated SNHG25/miR-497-5p/FASN pathway may be a promising target for the molecular-targeted management of EC.

lncRNA-ZFAS1 promotes the progression of endometrial carcinoma by targeting miR-34b to regulate VEGFA expression

Zinc finger nuclear transcription factor, X-box binding 1-type containing 1 antisense RNA 1 (ZFAS1) functions as an oncogenic long noncoding RNA (lncRNA) to promote proliferation and metastasis of endometrial carcinoma cell; however, the underlying mechanism has not been fully understood. First, RT-qPCR analysis of endometrial carcinoma tissues and cells showed that ZFAS1 was enriched in endometrial carcinoma tissues and cells. miR-34b was reduced in endometrial carcinoma and suggested negative correlation with ZFAS1 in endometrial carcinoma. Second, functional assays demonstrated that siRNA-mediated silence of ZFAS1 suppressed endometrial carcinoma cell proliferation and metastasis. Third, ZFAS1 bind to miR-34b and negatively regulate expression of miR-34b in endometrial carcinoma cells. miR-34b also bind to and negatively regulate expression of vascular endothelial growth factor A (VEGFA) in endometrial carcinoma cells. Lastly, knockdown of miR-34b counteracted with the suppressive effects of ZFAS1 silence on endometrial carcinoma cell proliferation and metastasis. In conclusion, lncRNA ZFAS1 functioned as an oncogene to promote endometrial carcinoma cell proliferation and metastasis through miR-34b/VEGFA axis.

Long non-coding RNA (lncRNA) HOXB-AS3 promotes cell proliferation and inhibits apoptosis by regulating ADAM9 expression through targeting miR-498-5p in endometrial carcinoma

Objective

Long non-coding RNA (lncRNA) expression is closely related to the pathogenesis and progression of various tumors. In this study, we investigated the mechanisms of lncRNA HOXB cluster antisense RNA 3 (HOXB-AS3), miRNA(miR)-498-5p, and disintegrin and metalloproteinase domain-containing protein 9 (ADAM9) in endometrial carcinoma (EC) cells.

Methods

The expression levels of lncRNA HOXB-AS3 in EC tissues and cells were detected using RT-qPCR assays. The effects of HOXB-AS3 knockdown on EC cell proliferation and apoptosis were measured using CCK-8 assays, colony formation assays, and flow cytometry. In addition, putative miR-498-5p binding sites were identified in HOXB-AS3 and ADAM9. The targeted relationships were further verified using dual-luciferase reporter and RNA pull-down assays.

Results

HOXB-AS3 expression was upregulated in EC tissues and cells. EC cell proliferation and viability decreased significantly in HOXB-AS3 knockdown groups. A putative miR-498-5p binding site in HOXB-AS3 was verified. Inhibition of miR-498-5p rescued the effects of HOXB-AS3 knockdown on cell proliferation and apoptosis. Finally, ADAM9 was verified as a direct target gene of miR-498-5p.

Conclusions

Our results suggest that lncRNA HOXB-AS3 is highly expressed in EC tissues and cells. Downregulation of HOXB-AS3 inhibits cell proliferation and promotes apoptosis in EC cells. HOXB-AS3 can upregulate ADAM9 expression by sponging miR-498-5p.

LINC01133 and LINC01243 are positively correlated with endometrial carcinoma pathogenesis

PURPOSE

To characterize the role of two long non-coding RNAs (lncRNAs), LINC01133 and LINC01243, in endometrial carcinoma (EC) pathogenesis. LINC01133 is an lncRNA that has been implicated in many cancers, and LINC01243 is a newly identified lncRNA identified from the NCBI GEO database.

METHODS

We studied the effect of LINC01133 and LINC01243 on EC malignancy using siRNA knockdown and real-time quantitative polymerase chain reaction (RT-qPCR), flow cytometry, Annexin V-FITC/propidium iodide double staining, Transwell, and scratch invasion assays in two EC cell lines (Ishikawa and HEC-1-A cells).

RESULTS

We first confirmed the partial knockdown of both LINC01133 and LINC01243 expression in Ishikawa and HEC-1-A cells using RT-qPCR. Following confirmation of lncRNA knockdown, we assessed the effect of knockdown on EC malignancy. We observed reduced EC cell proliferation using the CCK-8 assay, as well as cell cycle arrest and increased apoptosis in both EC cell lines. Furthermore, Transwell and scratch invasion assays revealed decreased migration and invasion of the two EC cell lines, respectively.

CONCLUSION

We demonstrated that LINC01133 and LINC01243 expression are associated with EC development and progression. Our findings suggest a potential role for these lncRNAs as novel EC biomarkers.

LINC00565 Enhances Proliferative Ability in Endometrial Carcinoma by Downregulating KLF9

Objective

To detect LINC00565 expression level in endometrial carcinoma (EC) samples and cell lines, and the correlations between LINC00565 and clinical features of EC patients. After intervening LINC00565, the underlying mechanism about proliferative ability in EC cell lines is observed.

Methods

Relative levels of LINC00565 and KLF9 in 52 paired EC and paracancerous tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The relationship between relative level of LINC00565 or KLF9 and clinical features of EC patients was analyzed. After knockdown of LINC00565 and KLF9, potential regulations of them on biological functions of EC were examined by Cell Counting Kit (CCK-8), colony formation assay and in vivo xenograft model in nude mice, respectively. At last, dual-luciferase reporter assay and rescue experiments were conducted to illustrate the mechanisms of LINC00565 and KLF9 in mediating the development of EC.

Results

LINC00565 was upregulated in EC tissues. Chi-square analysis showed that a high level of LINC00565 predicted large tumor size, advanced pathological staging and poor prognosis in EC. Silence of LINC00565 decreased proliferative ability in EC cells and tumor growth in nude mice bearing EC. KLF9 was the target gene of LINC00565. The negative interaction between LINC00565 and KLF9 was responsible for stimulating the malignant development of EC. Knockdown of KLF9 could abolish the regulatory effects of silenced LINC00565 on proliferative ability and tumorigenesis in EC.

Conclusion

LINC00565 is upregulated in EC tissues and closely linked to tumor size, pathological staging and poor prognosis in EC patients. LINC00565 stimulates proliferative ability in EC by downregulating KLF9.

Genome-wide analysis and functional prediction of the estrogen-regulated transcriptional response in the mouse uterus†

The ovarian hormones estrogen and progesterone orchestrate the transcriptional programs required to direct functions of the uterus for initiation and maintenance of pregnancy. Estrogen, acting via estrogen receptor alpha, regulates gene expression by activating and repressing distinct genes involved in signaling pathways that regulate cellular and physiological responses including cell division, water influx, and immune cell recruitment. Historically, these transcriptional responses have been postulated to reflect a biphasic physiological response. In this study, we explored the transcriptional responses of the ovariectomized mouse uterus to 17β-estradiol (E2) by RNA-seq to obtain global expression profiles of protein-coding transcripts (mRNAs) and long noncoding RNAs (lncRNAs) following 0.5, 1, 2, and 6 hours of treatment. The E2-regulated mRNA and lncRNA expression profiles in the mouse uterus indicate an association between lncRNAs and mRNAs that regulate E2-driven pathways and reproductive phenotypes in the mouse. The transient E2-regulated transcriptome is reflected in the time-dependent shifting of biological processes regulated in the uterus in response to E2. Moreover, high expression of some conserved lncRNAs that are E2 regulated in the mouse uterus are predictive of low overall survival in endometrial carcinoma patients (e.g., H19, KCNQ1OT1, MIR17HG, and FTX). Collectively, this study (1) describes a genomic approach for identifying E2-regulated lncRNAs that may serve critical function in the uterus and (2) provides new insights into our understanding of the regulation of hormone-regulated transcriptional responses with implications in pregnancy and endometrial pathologies.

Construction of a prognosis‑associated long noncoding RNA‑mRNA network for multiple myeloma based on microarray and bioinformatics analysis

At present, the association between prognosis-associated long noncoding RNAs (lncRNAs) and mRNAs is yet to be reported in multiple myeloma (MM). The aim of the present study was to construct prognostic models with lncRNAs and mRNAs, and to map the interactions between these lncRNAs and mRNAs in MM. LncRNA and mRNA data from 559 patients with MM were acquired from the Genome Expression Omnibus (dataset GSE24080), and their prognostic values were calculated using the survival package in R. Multivariate Cox analysis was used on the top 20 most significant prognosis-associated mRNAs and lncRNAs to develop prognostic signatures. The performances of these prognostic signatures were tested using the survivalROC package in R, which allows for time-dependent receiver operator characteristic (ROC) curve estimation. Weighted correlation network analysis (WGCNA) was conducted to investigate the associations between lncRNAs and mRNAs, and a lncRNA-mRNA network was constructed using Cytoscape software. Univariate Cox regression analysis identified 39 lncRNAs and 1,445 mRNAs that were significantly associated with event-free survival of MM patients. The top 20 most significant survival-associated lncRNAs and mRNAs were selected as candidates for analyzing independent MM prognostic factors. Both signatures could be used to separate patients into two groups with distinct outcomes. The areas under the ROC curves were 0.739 for the lncRNA signature and 0.732 for the mRNA signature. In the lncRNA-mRNA network, a total of 143 mRNAs were positively or negatively associated with 23 prognosis-associated lncRNAs. NCRNA00201, LOC115110 and RP5-968J1.1 were the most dominant drivers. The present study constructed a model that predicted prognosis in MM and formed a network with the corresponding prognosis-associated mRNAs, providing a novel perspective for the clinical diagnosis and treatment of MM, and suggesting novel directions for interpreting the mechanisms underlying the development of MM.

Specific trophoblast transcripts transferred by extracellular vesicles affect gene expression in endometrial epithelial cells and may have a role in embryo-maternal crosstalk

Background

Successful establishment of pregnancy hinges on appropriate communication between the embryo and the uterus prior to implantation, but the nature of this communication remains poorly understood. Here, we tested the hypothesis that the endometrium is receptive to embryo-derived signals in the form of RNA.

Methods

We have utilized a non-contact co culture system to simulate the conditions of pre implantation environment of the uterus. We bioorthogonally tagged embryonic RNA and tracked the transferred transcripts to endometrium. Transferred transcripts were separated from endometrial transcripts and sequenced. Changes in endometrial transcripts were quantified using quantitative PCR.

Results

We show that three specific transcripts are transferred to endometrial cells. We subsequently demonstrate a role of extracellular vesicles (EVs) in this process, as EVs obtained from cultured trophoblast spheroids incubated with endometrial cells induced down-regulation of all the three identified transcripts in endometrial cells.

Finally, we show that EVs/nanoparticles captured from conditioned culture media of viable embryos as opposed to degenerating embryos induce ZNF81 down-regulation in endometrial cells, hinting at the functional importance of this intercellular communication.

Conclusion

Ultimately, our findings demonstrate the existence of an RNA-based communication which may be of critical importance for the establishment of pregnancy.

lncRNA SNHG5 Modulates Endometrial Cancer Progression via the miR-25-3p/BTG2 Axis

Endometrial carcinoma (EC) is one of the most common malignancies of the female genital tract, although the mechanisms of EC initiation and development remain incompletely understood. In this study, we demonstrated that the noncoding RNA SNHG5 can inhibit the proliferation, migration, and invasion of EC cells by suppressing the expression of its putative target miR-25-3p. Overexpression of miR-25-3p significantly promoted the proliferation, migration, and invasion of EC cells. In addition, we showed that miR-25-3p represses the expression of BTG2 by directly binding to the 3′-UTR of BTG2 mRNA. Furthermore, increased miR-25-3p expression and decreased SNHG5 and BTG2 expression were observed in EC tissues, and the expression of SNHG5 was negatively correlated to that of miR-25-3p but positively correlated to that of BTG2. In summary, for the first time, we report that the SNHG5/miR-25-3p/BTG2 axis plays an important role in EC progression and is of great potential clinical significance for EC diagnosis and therapy.