KLF5-induced lncRNA IGFL2-AS1 promotes basal-like breast cancer cell growth and survival by upregulating the expression of IGFL1

The role of lnc‑MAPKAPK5‑AS1 in immune cell infiltration in hepatocellular carcinoma: Bioinformatics analysis and validation

The oncogenic and tumor suppressor roles of lnc-MAPKAPK5-AS1 in multiple cancers suggest its complexity in modulating cancer progression. The expression and promoter methylation level of lnc-MAPKAPK5-AS1 in hepatocellular carcinoma (HCC) was investigated through data mining from The Cancer Genome Atlas and Gene Expression Omnibus and its significance in prognosis and immunity was explored. lnc-MAPKAPK5-AS1 was co-expressed with its protein-coding gene MAPKAPK5 in HCC and exhibited upregulation in HCC tissues as a result of hypomethylation of its promoter region. High expression of lnc-MAPKAPK5-AS1 was associated with poor prognosis. Enrichment analysis revealed that lnc-MAPKAPK5-AS1 is involved in immune and metabolic-related pathways. Changes in the expression of lnc-MAPKAPK5-AS1 affected plasma cells, T cells CD4+ memory resting, NK cells, macrophages M0/M1, and mast cells resting in the tumor microenvironment. lnc-MAPKAPK5-AS1 was found to correlate with multiple immune checkpoints. Analysis of the Sangerbox database revealed positive relationships between expression of lnc-MAPKAPK5-AS1, tumor mutational burden and microsatellite instability, which suggested that immunotherapy may be effective in tumors with high expression of lnc-MAPKAPK5-AS1. The expression of lnc-MAPKAPK5-AS1 was verified to indicate sensitivity to 16 common targeted drugs. Immunohistochemistry confirmed the expression of MAPKAPK5 protein in HCC and its prognostic significance. Weighted gene co-expression network analysis was applied to identify hub genes related to both immunoreactive score and gene expression. These results revealed that lnc-MAPKAPK5-AS1 may be involved in the occurrence and development of HCC as an oncogene and may represent a potential therapeutic target through modulating the substance metabolism and immune response.

Positive Feedback Regulation between KLF5 and XPO1 Promotes Cell Cycle Progression of Basal like Breast Cancer

Basal-like breast cancer (BLBC), overlapping with the subgroup of estrogen receptor (ER), progesterone receptor (PR), and HER2 triple-negative breast cancer, has the worst prognosis and limited therapeutics. The XPO1 gene encodes nuclear export protein 1, a promising anticancer target which mediates nucleus-cytoplasm transport of nuclear export signal containing proteins such as tumor suppressor RB1 and some RNAs. Despite drugs targeting XPO1 are used in clinical, the regulation of XPO1 expression and functional mechanism is poorly understood, especially in BLBC. This study finds that KLF5 is a transcription factor of XPO1, which increases RB1 nuclear export and cell proliferation in BLBC cells. Furthermore, XPO1 interacts with the RNA-binding protein PTBP1 to export FOXO1 mRNA to cytoplasm and thus activates the FOXO1-KLF5 axis as a feedback. This work demonstrates that XPO1 inhibitor KPT-330 in combination with CDK4/6 inhibitor additively suppressed BLBC tumor growth in vivo. These results reveal a novel positive feedback regulation loop between KLF5 and XPO1 and provide a novel treatment strategy for BLBC.

Activation of the G Protein-Coupled Bile Acid Receptor TGR5 Modulates the HCP5/miR-139-5p/DDIT4 Axis to Antagonize Cervical Cancer Progression

A growing body of evidence indicates that the G protein-coupled bile acid receptor, TGR5, plays a critical role in multiple physiological processes ranging from metabolic disorders to cancers. However, the biological functions of TGR5 in cervical cancer (CC) have not been elucidated. Here, using TGR5 knockout mice, we found that a deficiency of TGR5 leads to greater sensitivity to the progression of cervical inflammation. Activation of TGR5 by its specific ligands significantly attenuated the malignant behavior of CC cells. In addition, we found that TGR5 can negatively modulate the expression of lncRNA HCP5 by blocking its transcription activation when mediated by p65. HCP5 was highly expressed in CC tissues, which was positively correlated with the poor prognosis of CC patients. HCP5 knockdown notably restrained CC cell proliferation, colony formation, and migration in vitro, and inhibited tumor growth in vivo. Furthermore, HCP5 can function as the molecular sponge for miR-139-5p to upregulate DNA damage-induced transcript 4 (DDIT4) in CC cells. Murine xenograft studies demonstrated that TGR5 suppressed the tumor formation of CC cells and downregulated HCP5 and DDIT4 while increasing miR-139-5p in the xenografts. Taken together, these findings, for the first time, indicate that TGR5 inhibits CC progression by regulating the HCP5/miR-139-5p/DDIT4 axis, suggesting that it may represent a novel and potent target for CC treatment.

Contribution of copy number variants on antipsychotic treatment response in Han Chinese patients with schizophrenia

BACKGROUND

Response to antipsychotic drugs (APD) varies greatly among individuals and is affected by genetic factors. This study aims to demonstrate genome-wide associations between copy number variants (CNVs) and response to APD in patients with schizophrenia.

METHODS

A total of 3030 patients of Han Chinese ethnicity randomly received APD (aripiprazole, olanzapine, quetiapine, risperidone, ziprasidone, haloperidol and perphenazine) treatment for six weeks. This study is a secondary data analysis. Percentage change on the Positive and Negative Syndrome Scale (PANSS) reduction was used to assess APD efficacy, and more than 50% change was considered as APD response. Associations between CNV burden, gene set, CNV loci and CNV break-point and APD efficacy were analysed.

FINDINGS

Higher CNV losses burden decreased the odds of 6-week APD response (OR = 0.66 [0.44, 0.98]). CNV losses in synaptic pathway involved in neurotransmitters were associated with 2-week PANSS reduction rate. CNV involved in sialylation (1p31.1 losses) and cellular metabolism (19q13.32 gains) associated with 6-week PANSS reduction rate at genome-wide significant level. Additional 36 CNVs associated with PANSS factors improvement. The OR of protective CNVs for 6-week APD response was 3.10 (95% CI: 1.33-7.19) and risk CNVs was 8.47 (95% CI: 1.92-37.43). CNV interacted with genetic risk score on APD efficacy (Beta = -1.53, SE = 0.66, P = 0.021). The area under curve to differ 6-week APD response attained 80.45% (95% CI: 78.07%-82.82%).

INTERPRETATION

Copy number variants contributed to poor APD efficacy and synaptic pathway involved in neurotransmitter was highlighted.

FUNDING

National Natural Science Foundation of China, National Key R&D Program of China, China Postdoctoral Science Foundation.

TEAD4: A key regulator of tumor metastasis and chemoresistance - Mechanisms and therapeutic implications

Cancer metastasis is a complex process influenced by various factors, including epithelial-mesenchymal transition (EMT), tumor cell proliferation, tumor microenvironment, and cellular metabolic status, which remains a significant challenge in clinical oncology, accounting for a majority of cancer-related deaths. TEAD4, a key mediator of the Hippo signaling pathway, has been implicated in regulating these factors that are all critical in the metastatic cascade. TEAD4 drives tumor metastasis and chemoresistance, and its upregulation is associated with poor prognosis in many types of cancers, making it an attractive target for therapeutic intervention. TEAD4 promotes EMT by interacting with coactivators and activating the transcription of genes involved in mesenchymal cell characteristics and extracellular matrix remodeling. Additionally, TEAD4 enhances the stemness of cancer stem cells (CSCs) by regulating the expression of genes associated with CSC maintenance. TEAD4 contributes to metastasis by modulating the secretion of paracrine factors and promoting heterotypic cellular communication. In this paper, we highlight the central role of TEAD4 in cancer metastasis and chemoresistance and its impact on various aspects of tumor biology. Understanding the mechanistic basis of TEAD4-mediated processes can facilitate the development of targeted therapies and combination approaches to combat cancer metastasis and improve treatment outcomes.

lncRNA ENST00000422059 promotes cell proliferation and inhibits cell apoptosis in breast cancer by regulating the miR-145-5p/KLF5 axis

Krüppel-like zinc-finger transcription factor 5 (KLF5) is a vital regulator of breast cancer (BC) onset and progression. The mechanism by which KLF5 regulates BC is still not clearly known. In this study, bioinformatics analysis shows that BC-affected individuals with elevated KLF5 expression levels have poor clinical outcomes. We further verify that miR-145-5p regulated KLF5 expression to promote cell apoptosis and inhibit cell proliferation in BC via dual-luciferase reporter assay, western blot analysis, qRT-PCR, CCK-8 assay and cell apoptosis assay. In addition, based on bioinformatics analysis, the binding of ENST00000422059 with miR-145-5p is confirmed by dual-luciferase reporter assay. Subsequently, FISH, western blot analysis, qRT-PCR, CCK-8 and cell apoptosis assays verified that ENST00000422059 increases KLF5 protein expression by sponging miRNA to promote cell proliferation and inhibit cell apoptosis. Finally, ENST00000422059 is found to accelerate tumor progression by regulating the miR-145-5p/KLF5 axis in vivo. In conclusion, this study suggests that ENST00000422059 upregulates KLF5 by sponging miR-145-5p to promote BC progression.

Basement Membrane-Associated lncRNA Risk Model Predicts Prognosis and Guides Clinical Treatment in Clear Cell Renal Cell Carcinoma

The basement membrane (BM) affects the invasion and growth of malignant tumors. The role and mechanism of BM-associated lncRNAs in clear cell renal cell carcinoma (ccRCC) are unknown. In this study, we identified biomarkers of ccRCC and developed a risk model to assess patient prognosis. We downloaded transcripts and clinical data from the Cancer Genome Atlas (TCGA). Differential analysis, co-expression analysis, Cox regression analysis, and lasso regression were used to identify BM-associated prognostic lncRNAs and create a risk prediction model. We evaluated and validated the accuracy of the model using multiple methods and constructed a nomogram to predict the prognosis of ccRCC. GO, KEGG, and immunity analyses were used to explore differences in biological function. We constructed a risk model containing six BM-associated lncRNAs (LINC02154, IGFL2-AS1, NFE4, AC112715.1, AC092535.5, and AC105105.3). The risk model has higher diagnostic efficiency compared to clinical characteristics and can be used to forecast patient prognoses. We used renal cancer cells and tissue microarrays to verify the expression of lncRNAs in the risk model. We found that knocking down LINC02154 and AC112715.1 could inhibit the invasion ability of renal cancer cells. The risk model based on BM-associated lncRNAs can well predict ccRCC and guide clinical treatment.

LINC00978 regulates metabolic rewiring to promote the malignancy of glioblastoma through AKR1B1

Glioma is a fatal primary brain tumor. Improved glioma treatment effectiveness depends on a better understanding of its underlying mechanisms. Herein, we reported LINC00978 overexpressed in gliomas. Downregulation of LINC00978 in glioblastoma cells inhibited cell proliferation, invasion, migration, and induced apoptosis. In vivo experiments confirmed that the CamK-A siRNA of LINC00978 could effectively inhibit the proliferation of glioma cells. The main pathway and genes regulated by LINC00978 were detected using RNA sequencing to elucidate the molecular mechanism. The results suggest that LINC00978 regulates the expression of genes related to metabolic pathways, including aldo-keto reductase family 1 member B (AKR1B1), which mediates the cytotoxicity of 2-deoxyglucose. LINC00978 positively regulated AKR1B1 expression, and 2-deoxyglucose induced AKR1B1 expression via a LINC00978-dependent mechanism. This research has revealed that LINC00978 promotes the sensitivity of glioma cells to 2DG. LINC00978 is highly expressed in most glioma patients. Thus, understanding the anticancer mechanism identified in this study may contribute to treating the majority of glioma patients. This study clarified the function and molecular mechanism of LINC00978 in glioblastoma and provided a study basis for LINC00978 to guide the clinical treatment of glioblastoma.

Kruppel-like factor 8 regulates triple negative breast cancer stem cell-like activity

Introduction

Breast tumor development is regulated by a sub-population of breast cancer cells, termed cancer stem-like cells (CSC), which are capable of self-renewing and differentiating, and are involved in promoting breast cancer invasion, metastasis, drug resistance and relapse. CSCs are highly adaptable, capable of reprogramming their own metabolism and signaling activity in response to stimuli within the tumor microenvironment. Recently, the nutrient sensor O-GlcNAc transferase (OGT) and O-GlcNAcylation was shown to be enriched in CSC populations, where it promotes the stemness and tumorigenesis of breast cancer cells in vitro and in vivo. This enrichment was associated with upregulation of the transcription factor Kruppel-like-factor 8 (KLF8) suggesting a potential role of KLF8 in regulating CSCs properties.

Methods

Triple-negative breast cancer cells were genetically modified to generate KLF8 overexpressing or KLF8 knock-down cells. Cancer cells, control or with altered KLF8 expression were analyzed to assess mammosphere formation efficiency, CSCs frequency and expression of CSCs factors. Tumor growth in vivo of control or KLF8 knock-down cells was assessed by fat-pad injection of these cell in immunocompromised mice.

Results

Here, we show that KLF8 is required and sufficient for regulating CSC phenotypes and regulating transcription factors SOX2, NANOG, OCT4 and c-MYC. KLF8 levels are associated with chemoresistance in triple negative breast cancer patients and overexpression in breast cancer cells increased paclitaxel resistance. KLF8 and OGT co-regulate each other to form a feed-forward loop to promote CSCs phenotype and mammosphere formation of breast cancer cells.

Discussion

These results suggest a critical role of KLF8 and OGT in promoting CSCs and cancer progression, that may serve as potential targets for developing strategy to target CSCs specifically.

Pan-cancer analysis reveals IGFL2 as a potential target for cancer prognosis and immunotherapy

Insulin-like growth factor like family member 2 (IGFL2) is a gene in the IGFL family, located on chromosome 19, whose role in cancer is unclear, and the aim of this study was to investigate the relevance of IGFL2 expression, prognosis, immunity, and mutation in pan-cancer. Obtaining information from The Cancer Genome Atlas and The Genotype-Tissue Expression Project (GTEx) databases for expression analysis and combining with The Gene Expression Profile Interaction Analysis database for prognostic aspects. Analysis of immune cell infiltration by TIMER and CIBERSORT algorithms. Calculation of correlation of immune-related genes with IGFL2 expression and tumor mutational burden and microsatellite instability. Mutations and DNA methylation were analyzed using the cBioPortal database and the UALCAN database, and functional enrichment was performed using Gene set enrichment analysis (GSEA). IGFL2 expression is significantly elevated in tumor tissue and high expression has a worse prognosis in most cancers. In immune correlation analysis, it was associated with most immune cells and immune-related genes. In most cancers, IGFL2 methylation is lower and the group with mutations in IGFL2 has a worse prognosis than the normal group. The GSEA analysis showed that IGFL2 was significantly enriched in signaling and metabolism. IGFL2 may be involved in the development of many types of cancer, influencing the course of cancer with different biological functions. It may also be a biomarker for tumor immunotherapy.

IGFL2-AS1, a Long Non-Coding RNA, Is Associated with Radioresistance in Colorectal Cancer

Precise prediction of radioresistance is an important factor in the treatment of colorectal cancer (CRC). To discover genes that regulate the radioresistance of CRCs, we analyzed an RNA sequencing dataset of patient-originated samples. Among various candidates, IGFL2-AS1, a long non-coding RNA (lncRNA), exhibited an expression pattern that was well correlated with radioresistance. IGFL2-AS1 is known to be highly expressed in various cancers and functions as a competing endogenous RNA. To further investigate the role of IGFL2-AS1 in radioresistance, which has not yet been studied, we assessed the amount of IGFL2-AS1 transcripts in CRC cell lines with varying degrees of radioresistance. This analysis showed that the more radioresistant the cell line, the higher the level of IGFL2-AS1 transcripts-a similar trend was observed in CRC samples. To directly assess the relationship between IGFL2-AS1 and radioresistance, we generated a CRC cell line stably expressing a small hairpin RNA (shRNA) targeting IGFL2-AS1. shRNA-mediated knockdown of IGFL2-AS1 decreased radioresistance and cell migration in vitro, establishing a functional role for IGFL2-AS1 in radioresistance. We also showed that downstream effectors of the AKT pathway played crucial roles. These data suggest that IGFL2-AS1 contributes to the acquisition of radioresistance by regulating the AKT pathway.

IGFL2‐AS1 ‐induced suppression of HIF ‐1α degradation promotes cell proliferation and invasion in colorectal cancer by upregulating CA9

PURPOSE

The lncRNA IGFL2-AS1 is a known cancer-promoting factor in colorectal cancer (CRC); nonetheless, the mechanism of its carcinogenic effects has not yet been elucidated. This study elaborated on the role and underlying molecular mechanism of IGFL2-AS1 in promoting CRC cell functions.

METHODS

IGLF2-AS1 expression levels in CRC tissue/normal tissue and CRC cell line/normal colon epithelial cell line were detected by quantitative real-time polymerase chain reaction. Cell counting kit-8, colony formation assay, and EdU assay were performed to assess the effect of IGFL2-AS1 knockdown or overexpression on the proliferative capacity of CRC cells. The migration and invasion abilities of LoVo cells were measured using transwell assay. The expression relationship between IGFL2-AS1 and carbonic anhydrase 9 (CA9) and the CA9 expression level in CRC tissues and cells was verified by transcriptome sequencing, western blotting, and immunohistochemical staining. Treatment with MG132 and cycloheximide was utilized to explore the mechanism by which IGFL2-AS1 affects the hypoxia-inducible factor-1α (HIF-1α)/CA9 pathway. A nude mouse xenograft model was constructed to evaluate the effect of IGFL2-AS1 on CRC growth in vivo.

RESULTS

We discovered that IGFL2-AS1 was highly upregulated in CRC tumor tissues and cells. IGFL2-AS1 can functionally promote CRC cell proliferation, migration, and invasion in vitro and accelerate CRC occurrence in vivo. Mechanistic studies demonstrated that IGFL2-AS1 upregulated the CA9 level by affecting the degradation pathway of HIF-1α, which elucidates its pro-proliferative effect in CRC. The lncRNA IGFL2-AS1 mediated the inhibition of HIF-1α degradation in CRC and increased CA9 expression, thereby promoting CRC progression.

CONCLUSION

Our findings suggested that IGFL2-AS1 is expected to be a promising new diagnostic marker and therapeutic target for CRC.

Insights into Early Onset Colorectal Cancer through Analysis of Normal Colon Organoids of Familial Adenomatous Polyposis Patients

Early onset colorectal cancer (EOCRC) rates have increased in recent decades. While lowering the recommended age for routine colonoscopies to 45 may reduce this burden, such measures do not address those who develop CRC before that age. Additional measures are needed to identify individuals at-risk for CRC. To better define transcriptomic events that precede the development of CRC, we performed RNA-sequencing analysis in colon organoids derived from seven healthy and six familial adenomatous polyposis (FAP) patients. This led to the identification of 2635 significant differentially expressed genes (FDR < 0.05). Through secondary analysis of publicly available datasets, we found that these genes were enriched for significant genes also present in FAP CRC and non-hereditary CRC datasets, including a subset that were unique to EOCRC. By exposing FAP colon organoids to a three-day ethanol treatment, we found that two EOCRC-relevant genes were also targets of CRC related lifestyle factors. Our data provides unique insight into the potential, early mechanisms of CRC development in colon epithelial cells, which may provide biomarkers for patient monitoring. We also show how modifiable lifestyle factors may further alter genes relevant to EOCRC, adding weight to the hypothesis that such factors represent an important contributor to increased EOCRC incidence.

Whole Transcriptome Analysis Identifies Platycodin D-Mediated RNA Regulatory Network in Non–Small-Cell Lung Cancer

Non–small-cell lung cancer (NSCLC) is one of the most fatal malignant tumors harmful to human health. Previous studies report that Platycodin D (PD) exhibits anti-tumor effects in multiple human cancers, including NSCLC, but the underlying mechanisms are largely unknown. Accumulating evidence indicates that non-coding RNAs (ncRNAs) participate in NSCLC disease progression, but the link between PD and the ncRNAs in NSCLC is poorly elucidated. Here, we used whole transcriptome sequencing to systematically investigate the RNAs-associated regulatory network in the PD treating NSCLC cell lines. A total of 942 significantly dysregulated RNAs were obtained. Among those, five circRNAs and six IncRNAs were rigorously selected via database and in vitro validation. In addition, the functional enrichment study of differentially expressed mRNAs, single nucleotide polymorphisms (SNPs) within PD-related mRNA structures, and the interaction between PD and mRNA-related proteins were analyzed through gene set enrichment analysis (GSEA), structural variant analysis, and molecular docking, respectively. With further in vitro validation, the results show that PD inhibits cell proliferation, arrests the cell cycle, and induces cell apoptosis through targeting BCL2-related proteins. We hope these data can provide a full concept of PD-related molecular changes, leading to a new treatment for NSCLC.

TEAD4 as an Oncogene and a Mitochondrial Modulator

TEAD4 (TEA Domain Transcription Factor 4) is well recognized as the DNA-anchor protein of YAP transcription complex, which is modulated by Hippo, a highly conserved pathway in Metazoa that controls organ size through regulating cell proliferation and apoptosis. To acquire full transcriptional activity, TEAD4 requires co-activator, YAP (Yes-associated protein) or its homolog TAZ (transcriptional coactivator with PDZ-binding motif) the signaling hub that relays the extracellular stimuli to the transcription of target genes. Growing evidence suggests that TEAD4 also exerts its function in a YAP-independent manner through other signal pathways. Although TEAD4 plays an essential role in determining that differentiation fate of the blastocyst, it also promotes tumorigenesis by enhancing metastasis, cancer stemness, and drug resistance. Upregulation of TEAD4 has been reported in several cancers, including colon cancer, gastric cancer, breast cancer, and prostate cancer and serves as a valuable prognostic marker. Recent studies show that TEAD4, but not other members of the TEAD family, engages in regulating mitochondrial dynamics and cell metabolism by modulating the expression of mitochondrial- and nuclear-encoded electron transport chain genes. TEAD4’s functions including oncogenic activities are tightly controlled by its subcellular localization. As a predominantly nuclear protein, its cytoplasmic translocation is triggered by several signals, such as osmotic stress, cell confluency, and arginine availability. Intriguingly, TEAD4 is also localized in mitochondria, although the translocation mechanism remains unclear. In this report, we describe the current understanding of TEAD4 as an oncogene, epigenetic regulator and mitochondrial modulator. The contributing mechanisms will be discussed.

Comprehensive Analysis of RNA-Seq in Endometriosis Reveals Competing Endogenous RNA Network Composed of circRNA, lncRNA and mRNA

Although long non coding RNAs (lncRNAs) and circular RNAs (circRNAs) play important roles in the pathogenesis of diseases, endometriosis related lncRNAs and circRNAs are still rarely reported. This study focused on the potential molecular mechanism of endometriosis related competitive endogenous RNA (ceRNA) composed of lncRNAs and circRNAs. We performed high-throughout sequencing of six normal endometria, six eutopic endometria and six ectopic endometria for the first time to describe and analyze the expression profile of lncRNA, circRNA and mRNA. Our results showed that 140 lncRNAs, 107 circRNAs and 1,206 mRNAs were differentially expressed in the ectopic group, compared with the normal and eutopic groups. We established an lncRNA/circRNA-mRNA co-expression network using pearson correlation test. Meanwhile, the results of Gene set enrichment analysis analysis showed that the 569 up-regulated differentially expressed mRNA (DEmRNA) were mainly related to the epithelial-mesenchymal transition, regulation of immune system process and immune effector process. Subsequently, we established a DElncRNA-miRNA and DEcircRNA-miRNA network using the starbase database, identified the common miRNAs and constructed DElncRNA/DEcircRNA-miRNA pairs. miRDB, Targetscan, miRwalk and circRNA/lncRNA-mRNA pairs jointly determined the miRNA-mRNA portion of the circRNA/lncRNA-miRNA-mRNA co-expression network. RT-qPCR results of 15 control samples and 25 ectopic samples confirmed that circGLIS2, circFN1, LINC02381, IGFL2-AS1, CD84, LYPD1 and FAM163A were significantly overexpressed in ectopic tissues. In conclusion, this is the first study to illustrate ceRNA composed of differentially expressed circRNA, lncRNA and mRNA in endometriosis. We also found that lncRNA and circRNA exerted a pivotal function on the pathogenesis of endometriosis, which can provide new insights for further exploring the pathogenesis of endometriosis and identifying new targets.

The EMT-induced lncRNA NR2F1-AS1 positively modulates NR2F1 expression and drives gastric cancer via miR-29a-3p/VAMP7 axis

Deregulated lncRNAs play critical roles in tumorigenesis and tumor progression. NR2F1-AS1 is an antisense lncRNA of NR2F1. However, the biological function of NR2F1-AS1 in gastric cancer (GC) remains largely unclear. In this study, we revealed that NR2F1-AS1 and NR2F1 were both positively correlated with the degree of malignancy and predicted poor prognosis in two independent GC cohorts. Besides, NR2F1-AS1 and NR2F1 can respond to Epithelial-to-mesenchymal transition (EMT) signaling in GC, since their expression was increased by TGF-beta treatment and decreased after stable overexpression of OVOL2 in GC cell lines. NR2F1-AS1 and NR2F1 were highly co-expressed in pan-tissues and pan-cancers. Depletion of NR2F1-AS1 compromised the expression level of NR2F1 in GC cells. Furthermore, NR2F1-AS1 knockdown inhibited the proliferation, migration, invasion and G1/S transition of GC cells. More importantly, transcriptome sequencing revealed a novel ceRNA network composed of NR2F1-AS1, miR-29a-3p, and VAMP7 in GC. The overexpression of VAMP7 predicted poor prognosis in GC. Rescue assay confirmed that NR2F1-AS1 promotes GC progression through miR-29a-3p/VAMP7 axis. Our finding highlights that the aberrant expression of NR2F1-AS1 is probably due to the abnormal EMT signaling in GC. LncRNA NR2F1-AS1 plays crucial roles in GC progression by modulating miR-29a-3p/VAMP7 axis, suggesting that NR2F1-AS1 may serve as a potential therapeutic target in GC.

Tumor microenvironment-related multigene prognostic prediction model for breast cancer

BACKGROUND

Breast cancer is an invasive disease with complex molecular mechanisms. Prognosis-related biomarkers are still urgently needed to predict outcomes of breast cancer patients.

METHODS

Original data were download from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO). The analyses were performed using perl-5.32 and R-x64-4.1.1.

RESULTS

In this study, 1086 differentially expressed genes (DEGs) were identified in the TCGA cohort; 523 shared DEGs were identified in the TCGA and GSE10886 cohorts. Eight subtypes were estimated using non-negative matrix factorization clustering with significant differences seen in overall survival (OS) and progression-free survival (PFS) (P < 0.01). Univariate Cox analysis and least absolute shrinkage and selection operator (LASSO) regression analysis were performed to develop a related risk score related to the 17 DEGs; this score separated breast cancer into low- and high-risk groups with significant differences in survival (P < 0.01) and showed powerful effectiveness (TCGA all group: 1-year area under the curve [AUC] = 0.729, 3-year AUC = 0.778, 5-year AUC = 0.781). A nomogram prediction model was constructed using non-negative matrix factorization clustering, the risk score, and clinical characteristics. Our model was confirmed to be related with tumor microenvironment. Furthermore, DEGs in high-risk breast cancer were enriched in histidine metabolism (normalized enrichment score [NES] = 1.49, P < 0.05), protein export (NES = 1.58, P < 0.05), and steroid hormone biosynthesis signaling pathways (NES = 1.56, P < 0.05).

CONCLUSIONS

We established a comprehensive model that can predict prognosis and guide treatment.