LncRNA KIAA0087 suppresses the progression of osteosarcoma by mediating the SOCS1/JAK2/STAT3 signaling pathway

Long non-coding RNA BCAR4 regulates osteosarcoma progression by targeting microRNA-1260a

Long non-coding RNAs (lncRNAs) play a crucial role in modulating cancer progression and metastasis. This study investigates the tumor-promoting function of long non-coding RNA BCAR4 in osteosarcoma and elucidates its regulatory mechanism. Although BCAR4 acts as a tumor promoter in osteosarcoma, its regulatory mechanism remains unclear. Bioinformatic analysis revealed a specific interaction between BCAR4 and miR-1260a, with osteosarcoma exhibiting elevated miR-1260a expression inversely correlated with BCAR4 expression. Overexpression of BCAR4 significantly suppressed miR-1260a expression, indicating regulation between BCAR4 and miR-1260a. Luciferase reporter assays confirmed a direct association between miR-1260a and BCAR4 at the sequence level. Silencing of BCAR4 inhibited osteosarcoma cell proliferation and migration while promoting cellular apoptosis, primarily mediated by miR-1260a. Our findings demonstrate that BCAR4 functions as a tumor promotor in osteosarcoma, and that its activity is regulated by miR-1260a. This study also proposes a potential therapeutic approach for treating osteosarcoma by targeting the BCAR4/miR-1260a axis. These different insights shed light on the intricate regulatory network underlying osteosarcoma pathogenesis and offer promising avenues for developing targeted therapies against this aggressive cancer.

Characterization of lncRNA-Driven Networks in Portal Vein Tumor Thrombosis: Implications for Hepatocellular Carcinoma Progression

Background: Portal vein tumor thrombosis (PVTT) is a frequent and serious complication of advanced hepatocellular carcinoma (HCC) that often results in poor prognosis. Although PVTT holds significant clinical relevance, the molecular mechanisms driving its formation are not well understood. Long non-coding RNAs (lncRNAs) have emerged as potential contributors to PVTT progression, prompting this study to explore lncRNAs as potential biomarkers for PVTT. Methods: We analyzed publicly available datasets from the Gene Expression Omnibus to identify differentially expressed lncRNAs and mRNAs across three comparisons: normal vs. HCC, normal vs. PVTT, and HCC vs. PVTT. Transcriptional profiles were characterized, and proteins interacting with HCC- and PVTT-specific lncRNAs were screened using online databases, revealing that all interacting proteins were transcription factors (TFs). We constructed lncRNA-TF-target gene regulatory networks by intersecting TF target genes with differentially expressed genes (DEGs) from each comparison. Protein-protein interaction (PPI) network analysis was performed to identify key clusters and hub genes, with TFs such as AR and ESR1 being highlighted. Gene Ontology analyses were conducted to understand the biological functions of the regulatory networks. Results: The study identified distinct transcriptional profiles for normal, HCC, and PVTT samples. Key regulatory networks, involving lncRNAs, TFs, and target genes, were constructed, and significant hub genes, including AR and ESR1, were identified as potential therapeutic targets. PPI network analysis revealed important clusters associated with PVTT progression, while Gene Ontology analyses provided insights into relevant biological functions. Conclusions: This study presents a novel framework for understanding lncRNA-TF-mediated gene regulation in PVTT. It identifies potential therapeutic targets and prognostic biomarkers that could facilitate the development of targeted therapies for PVTT, offering new opportunities to improve clinical outcomes.

Long Non-Coding RNAs: Key Regulators of Tumor Epithelial/Mesenchymal Plasticity and Cancer Stemness

Long non-coding RNAs (lncRNAs) are a class of non-coding RNA molecules with transcripts longer than 200 bp, which were initially thought to be noise from genomic transcription without biological function. However, since the discovery of H19 in 1980 and Xist in 1990, increasing evidence has shown that lncRNAs regulate gene expression at epigenetic, transcriptional, and post-transcriptional levels through specific regulatory actions and are involved in the development of cancer and other diseases. Despite many lncRNAs being expressed at lower levels than those of protein-coding genes with less sequence conservation across species, lncRNAs have become an intense area of RNA research. They exert diverse biological functions such as inducing chromatin remodeling, recruiting transcriptional machinery, acting as competitive endogenous RNAs for microRNAs, and modulating protein-protein interactions. Epithelial-mesenchymal transition (EMT) is a developmental process, associated with embryonic development, wound healing, and cancer progression. In the context of oncogenesis, the EMT program is transiently activated and confers migratory/invasive and cancer stem cell (CSC) properties to tumor cells, which are crucial for malignant progression, metastasis, and therapeutic resistance. Accumulating evidence has revealed that lncRNAs play crucial roles in the regulation of tumor epithelial/mesenchymal plasticity (EMP) and cancer stemness. Here, we summarize the emerging roles and molecular mechanisms of lncRNAs in regulating tumor cell EMP and their effects on tumor initiation and progression through regulation of CSCs. We also discuss the potential of lncRNAs as diagnostic and prognostic biomarkers and therapeutic targets.

RETRACTION: CircRNA EPHB4 modulates stem properties and proliferation of gliomas via sponging miR-637 and up-regulating SOX10

Retraction: C. Jin, J. Zhao, Z-P. Zhang, M. Wu, J. Li, B. Liu, X-B. Liao, Y-X. Liao, and J-P. Liu, "CircRNA EPHB4 modulates stem properties and proliferation of gliomas via sponging miR-637 and up-regulating SOX10," Molecular Oncology 15, no. 2 (2020): 596-622, https://doi.org/10.1002/1878-0261.12830. The above article, version of record published online on 16 December 2020 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor-in-Chief, Kevin Ryan; FEBS Press; and John Wiley & Sons Ltd. The journal began an investigation following a report from a third party regarding image duplication in Figure 14H between this article and the following articles: Gong et al. [1] and Zhao, et al. [2]. The authors did not respond to requests by the journal and the publisher for original data and an explanation. The retraction has been agreed because the evidence of image duplication across other articles substantially compromises the conclusions of the article. The authors did not respond to our notice of retraction. References [1] H. Gong, Y. Tao, S. Xiao, X. Li, K. Fang, J. Wen, P. He, and Ming, Z. "LncRNA KIAA0087 suppresses the progression of osteosarcoma by mediating the SOCS1/JAK2/STAT3 signaling pathway," Experimental & Molecular Medicine 55 (2023): 831-843, https://doi.org/10.1038/s12276-023-00972-8. [2] Y. Zhao, C. Li, Y. Zhang, and Z. Li. "CircTMTC1 contributes to nasopharyngeal carcinoma progression through targeting miR-495-MET-eIF4G1 translational regulation axis," Cell Death & Disease 13, no. 250 (2022), https://doi.org/10.1038/s41419-022-04686-z.

Stratifying osteosarcoma patients using an epigenetic modification-related prognostic signature: implications for immunotherapy and chemotherapy selection

Background

Osteosarcoma (OS) poses significant challenges in treatment and lacks reliable prognostic markers. Epigenetic alterations play a crucial role in disease progression. This study aimed to develop an accurate prognostic signature for OS using epigenetic modification genes (EMGs).

Methods

The Therapeutically Applicable Research to Generate Effective Treatments (TARGET)-OS cohort was analyzed. Univariate Cox analysis identified survival-associated EMGs. Based on least absolute shrinkage and selection operator (LASSO) regression and multivariate analysis, a 6-gene prognostic signature termed the epigenetic modification-related prognostic signature (EMRPS) was derived in the testing cohort. Kaplan-Meier and receiver operating characteristic (ROC) curve analysis confirmed predictive accuracy through internal and external validation (GEO accession GSE21257). A prognostic nomogram incorporating EMRPS and clinical features was constructed. Transcriptomic analysis including differential gene expression, Gene Ontology (GO), gene set enrichment analysis (GSEA), and immune infiltration analysis was conducted to explore mechanisms linking EMRPS to OS prognosis. Additionally, EMRPS impact on drug sensitivity was predicted.

Results

A 6-gene EMRPS comprising DDX24, DNAJC1, HDAC4, SIRT7, SP140 and UHRF2 was successfully developed. The high-risk group showed significantly shorter survival, consistently observed in both internal and external validation. EMRPS demonstrated high predictive efficacy for 1-, 3-, and 5-year overall survival, with area under curve (AUC) >0.85 in training and ~0.7 in testing. The nomogram integrating age, gender, metastasis status, and EMRPS exhibited high predictive performance based on concordance index analysis. Mechanistic analysis indicated the low-risk group had increased immune infiltration and activity with higher immune checkpoint expression, reflecting an immune-activated tumor microenvironment (TME) suitable for immunotherapy. Drug sensitivity analysis revealed the low-risk group had increased sensitivity to cisplatin, a first-line OS chemotherapy.

Conclusions

Our study successfully established an efficient EMRPS and nomogram, highlighting their potential as novel prognostic markers and indicators for selecting appropriate immunotherapy and chemotherapy candidates in OS treatment.

Targeted silencing of SOCS1 by DNMT1 promotes stemness of human liver cancer stem-like cells

BACKGROUND

Human liver cancer stem-like cells (HLCSLCs) are widely acknowledged as significant factors in the recurrence and eradication of hepatocellular carcinoma (HCC). The sustenance of HLCSLCs' stemness is hypothesized to be intricately linked to the epigenetic process of DNA methylation modification of genes associated with anticancer properties. The present study aimed to elucidate the stemness-maintaining mechanism of HLCSLCs and provide a novel idea for the clearance of HLCSLCs.

METHODS

The clinical relevance of DNMT1 and SOCS1 in hepatocellular carcinoma (HCC) patients was evaluated through the GEO and TCGA databases. Cellular immunofluorescence assay, methylation-specific PCR, chromatin immunoprecipitation were conducted to explore the expression of DNMT1 and SOCS1 and the regulatory relationship between them in HLCSLCs. Spheroid formation, soft agar colony formation, expression of stemness-associated molecules, and tumorigenicity of xenograft in nude mice were used to evaluate the stemness of HLCSLCs.

RESULTS

The current analysis revealed a significant upregulation of DNMT1 and downregulation of SOCS1 in HCC tumor tissues compared to adjacent normal liver tissues. Furthermore, patients exhibiting an elevated DNMT1 expression or a reduced SOCS1 expression had low survival. This study illustrated the pronounced expression and activity of DNMT1 in HLCSLCs, which effectively targeted the promoter region of SOCS1 and induced hypermethylation, consequently suppressing the expression of SOCS1. Notably, the stemness of HLCSLCs was reduced upon treatment with DNMT1 inhibitors in a concentration-dependent manner. Additionally, the overexpression of SOCS1 in HLCSLCs significantly mitigated their stemness. The knockdown of SOCS1 expression reversed the effect of DNMT1 inhibitor on the stemness of HLCSLCs. DNMT1 directly binds to the SOCS1 promoter. In vivo, DNMT1 inhibitors suppressed SOCS1 expression and inhibited the growth of xenograft.

CONCLUSION

DNMT1 targets the promoter region of SOCS1, induces hypermethylation of its CpG islands, and silences its expression, thereby promoting the stemness of HLCSLCs.

HOXB5 promotes the progression and metastasis of osteosarcoma cells by activating the JAK2/STAT3 signalling pathway

Objective

To investigate the involvement of the homeobox gene B5 (HOXB5) in the progression and metastasis of osteosarcoma.

Methods

The expression of HOXB5 in human osteosarcoma tissues and its correlation with clinical indicators were investigated using bioinformatics analysis and immunohistochemical labelling. Human osteosarcoma cells (HOS, MG63, U2OS, and Saos-2) and normal human osteoblasts (hFOB1.19) were cultivated. The expression of HOXB5 in these cells was detected using western blotting (WB) and RT‒PCR. Two cell lines exhibiting elevated HOXB5 expression were chosen and divided into three groups: the blank group (mock), control group (control) and transfection group (shHOXB5). The transfection group was infected with lentivirus expressing shRNAs targeting HOXB5. The transfection efficiency was detected by WB. Cell proliferation suppression was measured by CCK-8 and 5-ethynyl-2'-deoxyuridine (EdU) assays; the percentage of apoptotic cells was determined by flow cytometry; and cell migration and invasion were detected via the Transwell chamber test. WB was utilized to determine the protein expression of genes linked to metastasis (MMP2, MMP9), apoptosis (Bax, Bcl-2), and the JAK2/STAT3 pathway (JAK2, p-JAK2, STAT3, p-STAT3).

Results

In osteosarcoma tissues, HOXB5 expression was elevated and strongly correlated with distant metastasis. Silencing HOXB5 reduced the proliferation, migration and invasion of osteosarcoma cells; prevented the progression and metastasis of tumours in tumour-bearing nude mice; and reduced the activation of key proteins in the JAK2/STAT3 signalling pathway.

Conclusion

Through the JAK2/STAT3 signalling pathway, HOXB5 plays a crucial role in the malignant progression of osteosarcoma and is a promising target for osteosarcoma treatment.

Role of STAT3 in cancer cell epithelial‑mesenchymal transition (Review)

Since its discovery, the role of the transcription factor, signal transducer and activator of transcription 3 (STAT3), in both normal physiology and the pathology of numerous diseases, including cancer, has been extensively studied. STAT3 is aberrantly activated in different types of cancer, fulfilling a critical role in cancer progression. The biological process, epithelial‑mesenchymal transition (EMT), is indispensable for embryonic morphogenesis. During the development of cancer, EMT is hijacked to confer motility, tumor cell stemness, drug resistance and adaptation to changes in the microenvironment. The aim of the present review was to outline recent advances in knowledge of the role of STAT3 in EMT, which may contribute to the understanding of the function of STAT3 in EMT in various types of cancer. Delineating the underlying mechanisms associated with the STAT3‑EMT signaling axis may generate novel diagnostic and therapeutic options for cancer treatment.

Nafamostat mesylate sensitizes ovarian cancer cells to carboplatin by promoting the ZNF24-mediated inhibition of WNT2B

Resistance to chemotherapeutic medicines complicates and eventually kills people with ovarian cancer. Nafamostat mesylate (NM) has been used as an adjuvant therapy to enhance chemotherapy sensitivity in several cancers. This study aimed to evaluate the effect of NM on ovarian cancer cells susceptible to carboplatin (CBP) and to determine the underlying mechanism involved. Herein, qRT-PCR, western blot, and IHC were used to analyze mRNA and protein expression. Cell viability and proliferation were measured using the MTT and colony formation assays. Cell migration and invasion were examined using the Transwell assay. Flow cytometry was employed to detect cell apoptosis. The interaction between zinc finger protein 24 (ZNF24) and wingless-type MMTV integration site family member 2b (WNT2B) was validated via the dual-luciferase reporter and Chromatin immunoprecipitation assays. A xenograft nude mouse model was used to assess the effect of NM on CBP sensitivity in vivo. Our results showed that NM intervention inhibited the viability, proliferation, migration, and invasion and facilitated the apoptosis of CBP-resistant ovarian cancer cells. Furthermore, NM sensitized ovarian cancer cells to CBP by upregulating ZNF24. ZNF24 inactivated Wnt/β-catenin signaling by inhibiting the transcription of WNT2B. Additionally, NM enhanced the inhibitory effect of CBP on tumor growth in vivo. Taken together, NM enhanced the CBP sensitivity of ovarian cancer cells by promoting the ZNF24-mediated inactivation of the WNT2B/Wnt/β-catenin axis. These findings suggest a viable treatment approach for improving CBP resistance in ovarian cancer.

Mitigation of Sepsis-Induced Acute Lung Injury by BMSC-Derived Exosomal miR-125b-5p Through STAT3-Mediated Suppression of Macrophage Pyroptosis

Introduction

Sepsis is a syndrome characterized by high morbidity and mortality rates. One of its most severe complications is acute lung injury, which exhibits a multitude of clinical and biological features, including macrophage pyroptosis. This study investigates the regulatory effects of exosomes derived from Bone Marrow-Derived Mesenchymal Stem Cells (BMSCs) on sepsis-associated acute lung injury (ALI) and explores the potential mechanisms mediated by exosomal miRNAs.

Methods

Exosomes were isolated from primary BMSCs of adult C57BL/6J mice using differential centrifugation. Their uptake and distribution in both in vitro and in vivo contexts were validated. Key sepsis-associated hub gene signal transducer and activator of transcription 3 (STAT3) and its upstream non-coding miR-125b-5p were elucidated through a combination of bioinformatics, machine learning, and miRNA sequencing. Subsequently, the therapeutic potential of BMSC-derived exosomes in alleviating sepsis-induced acute lung injury was substantiated. Moreover, the functionalities of miR-125b-5p and STAT3 were corroborated through miR-125b-5p inhibitor and STAT3 agonist interventions, employing gain and loss-of-function strategies both in vitro and in vivo. Finally, a dual-luciferase reporter assay reaffirmed the interaction between miR-125b-5p and STAT3.

Results

We isolated exosomes from primary BMSCs and confirmed their accumulation in the mouse lung as well as their uptake by macrophages in vitro. This study identified the pivotal sepsis-associated hub gene STAT3 and demonstrated that exosomes derived from BMSCs can target STAT3, thereby inhibiting macrophage pyroptosis. MiR-125b-5p inhibition experiments showed that exosomes mitigate macrophage pyroptosis and lung injury by delivering miR-125b-5p. STAT3 overexpression experiments validated that miR-125b-5p reduces macrophage pyroptosis and lung injury by suppressing STAT3. Furthermore, a dual-luciferase reporter assay confirmed the binding interaction between miR-125b-5p and STAT3.

Conclusion

Exosomes derived from BMSCs, serving as carriers for delivering miR-125b-5p, can downregulate STAT3, thereby inhibiting macrophage pyroptosis and alleviating sepsis-associated ALI. These significant findings provide valuable insights into the potential development of ALI therapies centred around exosomes derived from BMSC.