LncRNA-Dependent Mechanisms of Transforming Growth Factor-β: From Tissue Fibrosis to Cancer Progression

MicroRNA‑96 promotes the proliferation and migration of breast cancer cells by inhibiting Smad7 expression

The present study aimed to investigate the effects of microRNA (miR)-96 on the proliferation and migration of breast cancer cells, and indicated that miR-96 may have a promoting role in breast cancer by inhibiting Smad7. Reverse transcription-quantitative (RT-q)PCR was used to detect the expression levels of miR-96 and Smad7 in breast cancer tissues and adjacent tissues. Western blotting and immunohistochemistry were conducted to determine the expression levels of SMAD7 in breast cancer and adjacent tissues. A dual luciferase assay was performed to verify the targeted binding between miR-96 and Smad7. Furthermore, the different expression patterns of miR-96 and Smad7 were compared in various breast cancer cell lines using RT-qPCR and western blotting. Among these cell lines, MDA-MB-231, which exhibited the highest expression of miR-96, was chosen for subsequent functional verification. The expression levels of miR-96 were significantly higher in breast cancer tissues compared with those in adjacent tissues. By contrast, the expression levels of Smad7 were significantly lower in breast cancer tissues compared with those in adjacent tissues. The dual luciferase assay revealed a targeted binding effect between miR-96 and Smad7. Notably, transfection with miR-96-5p mimics and short hairpin RNA-Smad7 markedly promoted the proliferation, adhesion, invasion and migration of breast cancer cells. Conversely, transfection with a miR-96-5p inhibitor and Smad7 overexpression plasmid exhibited the opposite trend. In conclusion, the expression levels of miR-96 were significantly elevated in breast cancer tissues compared with those in adjacent tissues. Overexpression of miR-96 was shown to promote the migration of breast cancer cells by downregulating the expression of Smad7. These findings indicated that miR-96 may serve as a prognostic marker for breast cancer.

Silencing LncRNA SNHG14 alleviates renal tubular injury via the miR-483-5p/HDAC4 axis in diabetic kidney disease

PURPOSE

This study explored the clinical value of long non-coding RNA small nucleolar RNA host gene 14 (SNHG14) in diabetic kidney disease (DKD) and the mechanism of renal tubular injury.

METHODS

Patients with DKD, type 2 diabetes mellitus (T2DM) and healthy individuals (HVs) were included, as well as the human proximal tubular epithelial cell line (HK-2) induced by high glucose was also included. The mRNA levels of SNHG14 in the serum and cells were detected using RT-qPCR. Diagnostic significance was examined using receiver operating characteristic (ROC) analysis. A commercial test kit, flow cytometry, and enzyme-linked immunosorbent assays were employed to assess reactive oxygen species (ROS) production, apoptosis, inflammatory factor secretion, and extracellular matrix protein levels in HK-2 cells. The dual-luciferase reporter assay and RNA immunoprecipitation were used to validate miR-483-5p concerning SNHG14 or histone deacetylase 4 (HDAC4).

RESULTS

SNHG14 and HDAC4 levels were elevated in the serum of DKD patients and HG-induced HK-2 cells, while miR-483-5p levels were decreased (P < 0.001). SNHG14 increased HDAC4 levels by sponging miR-483-5p. Elevated SNHG14 levels significantly differentiated DKD patients from HVs (AUC = 0.944) and T2DM (AUC = 0.867). Silencing of SNHG14 alleviated HG-induced ROS production and apoptosis as well as the over-secretion of inflammatory factors and extracellular matrix proteins; however, this alleviation was typically suppressed by low expression of miR-483-5p (P < 0.001). Elevated miR-483-5p alleviates HG-induced renal tubular injury, but this alleviation is suppressed by HDAC4 overexpression.

CONCLUSION

In summary, suppression of SNHG14 has been shown in our study to mitigate renal tubular injury in DKD by regulating apoptosis, oxidative stress, inflammation, and fibrosis through the miR-483-5p/HDAC4 axis.

Development of a Novel Prognostic Model for Lung Adenocarcinoma Utilizing Pyroptosis-Associated LncRNAs

Lung cancer is a highly prevalent and fatal cancer that seriously threatens the safety of people in various regions around the world. Difficulty in early diagnosis and strong drug resistance have always been difficulties in the treatment of lung cancer, so the prognosis of lung cancer has always been the focus of scientific researchers. This study used genotype-tissue expression (GTEx) and the cancer genome atlas (TCGA) databases to obtain 477 lung adenocarcinoma (LUAD) and 347 healthy individuals' samples as research subjects and divided LUAD patients into low-risk and high-risk groups based on prognostic risk scores. Differentially expressed gene (DEG) analysis was performed on 25 pyroptosis-related genes obtained from GeneCards and MSigDB databases in cancer tissues of LUAD patients and noncancerous tissues of healthy individuals, and seven genes were significantly different in cancer tissues and noncancerous tissues among them. Coexpression analysis and differential expression analysis of these genes and long noncoding RNAs (lncRNAs) found that three lncRNAs (AC012615.1, AC099850.3, and AO0001453.2) had significant differences in expression between cancer tissues and noncancerous tissues. We used Cox regression and the least absolute shrinkage sum selection operator (LASSO) regression to construct a prognostic model for LUAD patients with these three pyroptosis-related lncRNAs (pRLs) and analyzed the prognostic value of the pRLs model by the Likaplan-Meier curve and Cox regression. The results show that the risk prediction model has good prediction ability. In addition, we also studied the differences in tumor mutation burden (TMB), tumor immune dysfunction and rejection (TIDE), and immune microenvironment with pRLs risk scores in low-risk and high-risk groups. This study successfully established a LUAD prognostic model based on pRLs, which provides new insights into lncRNA-based LUAD diagnosis and treatment strategies.

Long journey on the role of long non-coding RNA (lncRNA) in acute kidney injury (AKI)

Acute kidney injury (AKI) has a high rate of morbidity, death, and medical expenses, making it a worldwide public health problem. There are still few viable treatment plans for AKI despite medical advancements. A subclass of non-coding RNAs with over 200 nucleotides in length, long non-coding RNAs (lncRNAs) have a wide range of biological roles. Lately, lncRNAs have become important mediators of AKI and prospective biomarkers. However, current studies show that, via constructing the lncRNA/microRNA/target gene regulatory axis, abnormal expression of lncRNAs has been connected to significant pathogenic processes associated with AKI, such as the inflammatory response, cell proliferation, and apoptosis. In order to compete with mRNAs for binding to the same miRNAs and affect the expression of transcripts targeted by miRNAs, lncRNAs may function as competing endogenous RNAs (ceRNAs). The most widely used approach for researching the biological roles of lncRNAs is the construction of ceRNA regulation networks. Our goal in this article is to deliver an updated review of lncRNAs in AKI and to provide more knowledge on their possible applications as therapeutic targets and AKI biomarkers.

The regulatory process and practical significance of non-coding RNA in the dissemination of prostate cancer to the skeletal system

Prostate cancer is a major contributor to male cancer-related mortality globally. It has a particular affinity for the skeletal system with metastasis to bones seriously impacting prognosis. The identification of prostate cancer biomarkers can significantly enhance diagnosis and patient monitoring. Research has found that cancer and metastases exhibit abnormal expression of numerous non-coding RNA. Some of these RNA facilitate prostate cancer bone metastasis by activating downstream signaling pathways, while others inhibit this process. Elucidating the functional processes of non-coding RNA in prostate cancer bone metastasis will likely lead to innovative treatment strategies for this malignant condition. In this review, the mechanistic role of the various RNA in prostate cancer is examined. Our goal is to provide a new avenue of approach to the diagnosis and treatment of bone metastasis in this cancer.

HOXA5-induced lncRNA DNM3OS promotes human embryo lung fibroblast fibrosis via recruiting EZH2 to epigenetically suppress TSC2 expression

Background

Idiopathic pulmonary fibrosis (IPF) is an unrepairable disease that results in lung dysfunction and decreased quality of life. Prevention of pulmonary fibrosis is challenging, while its pathogenesis remains largely unknown. Herein, we investigated the effect and mechanism of long non-coding RNA (lncRNA) DNM3OS/Antisense RNA in the pathogenesis of pulmonary fibrosis.

Methods

EdU (5-ethynyl-2'-deoxyuridine) and wound healing assays were employed to evaluate the role of DNM3OS on cell proliferation and migration. Western blot detected the proteins expressions of alpha-smooth muscle actin (α-SMA), vimentin, and fibronectin. The interactions among genes were evaluated by RNA pull-down, luciferase reporter, RNA immunoprecipitation (RIP), chromatin immunoprecipitation (ChIP) and chromatin Isolation by RNA purification (ChIRP) assays.

Results

DNM3OS was upregulated by transforming growth factor beta 1 (TGF-β1) in a dose- and time-dependent manner. DNM3OS knockdown repressed the growth and migration of lung fibroblast, and fibrotic gene expression (CoL1α1, CoL3α1, α-SMA, vimentin, and fibronectin), while suppression of TSC2 accelerated the above process. DNM3OS recruited EZH2 to the promoter region of TSC2, increased the occupancy of EZH2 and H3K27me3, and thereby suppressed the expression of TSC2. HOXA5 promoted the transcription of DNM3OS.

Conclusions

HOXA5-induced DNM3OS promoted the proliferation, migration, and expression of fibrosis-related genes in human embryo lung fibroblast via recruiting EZH2 to epigenetically suppress the expression of TSC2.

Hematopoietic Transcription Factor RUNX1 is Essential for Promoting Macrophage-Myofibroblast Transition in Non-Small-Cell Lung Carcinoma

Macrophage-myofibroblast transition (MMT) is a newly discovered pathway for mass production of pro-tumoral cancer-associated fibroblasts (CAFs) in non-small cell lung carcinoma (NSCLC) in a TGF-β1/Smad3 dependent manner. Better understanding its regulatory signaling in tumor microenvironment (TME) may identify druggable target for the development of precision medicine. Here, by dissecting the transcriptome dynamics of tumor-associated macrophage at single-cell resolution, a crucial role of a hematopoietic transcription factor Runx1 in MMT formation is revealed. Surprisingly, integrative bioinformatic analysis uncovers Runx1 as a key regulator in the downstream of MMT-specific TGF-β1/Smad3 signaling. Stromal Runx1 level positively correlates with the MMT-derived CAF abundance and mortality in NSCLC patients. Mechanistically, macrophage-specific Runx1 promotes the transcription of genes related to CAF signatures in MMT cells at genomic level. Importantly, macrophage-specific genetic deletion and systemic pharmacological inhibition of TGF-β1/Smad3/Runx1 signaling effectively prevent MMT-driven CAF and tumor formation in vitro and in vivo, representing a potential therapeutic target for clinical NSCLC.

Tumour-associated macrophages: versatile players in the tumour microenvironment

Tumour-Associated Macrophages (TAMs) are one of the pivotal components of the tumour microenvironment. Their roles in the cancer immunity are complicated, both pro-tumour and anti-cancer activities are reported, including not only angiogenesis, extracellular matrix remodeling, immunosuppression, drug resistance but also phagocytosis and tumour regression. Interestingly, TAMs are highly dynamic and versatile in solid tumours. They show anti-cancer or pro-tumour activities, and interplay between the tumour microenvironment and cancer stem cells and under specific conditions. In addition to the classic M1/M2 phenotypes, a number of novel dedifferentiation phenomena of TAMs are discovered due to the advanced single-cell technology, e.g., macrophage-myofibroblast transition (MMT) and macrophage-neuron transition (MNT). More importantly, emerging information demonstrated the potential of TAMs on cancer immunotherapy, suggesting by the therapeutic efficiency of the checkpoint inhibitors and chimeric antigen receptor engineered cells based on macrophages. Here, we summarized the latest discoveries of TAMs from basic and translational research and discussed their clinical relevance and therapeutic potential for solid cancers.

The long non-coding RNA LINC00707 interacts with Smad proteins to regulate TGFβ signaling and cancer cell invasion

BACKGROUND

Long non-coding RNAs (lncRNAs) regulate cellular processes by interacting with RNAs or proteins. Transforming growth factor β (TGFβ) signaling via Smad proteins regulates gene networks that control diverse biological processes, including cancer cell migration. LncRNAs have emerged as TGFβ targets, yet, their mechanism of action and biological role in cancer remain poorly understood.

METHODS

Whole-genome transcriptomics identified lncRNA genes regulated by TGFβ. Protein kinase inhibitors and RNA-silencing, in combination with cDNA cloning, provided loss- and gain-of-function analyses. Cancer cell-based assays coupled to RNA-immunoprecipitation, chromatin isolation by RNA purification and protein screening sought mechanistic evidence. Functional validation of TGFβ-regulated lncRNAs was based on new transcriptomics and by combining RNAscope with immunohistochemical analysis in tumor tissue.

RESULTS

Transcriptomics of TGFβ signaling responses revealed down-regulation of the predominantly cytoplasmic long intergenic non-protein coding RNA 707 (LINC00707). Expression of LINC00707 required Smad and mitogen-activated protein kinase inputs. By limiting the binding of Krüppel-like factor 6 to the LINC00707 promoter, TGFβ led to LINC00707 repression. Functionally, LINC00707 suppressed cancer cell invasion, as well as key fibrogenic and pro-mesenchymal responses to TGFβ, as also attested by RNA-sequencing analysis. LINC00707 also suppressed Smad-dependent signaling. Mechanistically, LINC00707 interacted with and retained Smad proteins in the cytoplasm. Upon TGFβ stimulation, LINC00707 dissociated from the Smad complex, which allowed Smad accumulation in the nucleus. In vivo, LINC00707 expression was negatively correlated with Smad2 activation in tumor tissues.

CONCLUSIONS

LINC00707 interacts with Smad proteins and limits the output of TGFβ signaling, which decreases LINC00707 expression, thus favoring cancer cell invasion. Video Abstract.

Role of Non-Coding RNAs in TGF-β Signalling in Glioma

Brain tumours and Gliomas, in particular, are among the primary causes of cancer mortality worldwide. Glioma diagnosis and therapy have not significantly improved despite decades of efforts. Autocrine TGF-β signalling promotes glioma proliferation, invasion, epithelial-to-mesenchymal transition (EMT), and drug resistance. Non-coding RNAs such as miRNA, lncRNA, and circRNAs have emerged as critical transcriptional and post-transcriptional regulators of TGF-β pathway components in glioma. Here, we summarize the complex regulatory network among regulatory ncRNAs and TGF-β pathway during Glioma pathogenesis and discuss their role as potential therapeutic targets for Gliomas.