miR-770-5p regulates EMT and invasion in TNBC cells by targeting DNMT3A

TRIM29 facilitates gemcitabine resistance via MEK/ERK pathway and is modulated by circRPS29/miR-770-5p axis in PDAC

AIMS

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease. Chemotherapy based on gemcitabine (GEM) remains the first-line drug for patients with advanced PDAC. However, GEM resistance impairs its therapeutic effectiveness. Therefore, identifying effective therapeutic targets are urgently needed to overcome GEM resistance.

METHODS

The clinical significance of Tripartite Motif Containing 29 (TRIM29) was identified by exploring GEO datasets and TCGA database and its potential biological functions were predicted by GSEA analysis. The regulatory axis was established by bioinformatics analysis and validated by mechanical experiments. Then, in vitro and in vivo assays were performed to validate the roles of TRIM29 in PDAC GEM resistance.

RESULTS

High TRIM29 expression was associated with poor prognosis of PDAC and functional experiments demonstrated that TRIM29 promoted GEM resistance in PDAC GEM-resistant (GR) cells. Furthermore, we revealed that circRPS29 promoted TRIM29 expression via competitive interaction with miR-770-5p and then activated MEK/ERK signaling pathway. Additionally, both in vitro and in vivo functional experiments demonstrated that circRPS29/miR-770-5p/TRIM29 axis promoted PDAC GEM resistance via activating MEK/ERK signaling pathway.

CONCLUSION

Our results identify the significance of the signaling axis, circRPS29/miR-770-5p/TRIM29-MEK/ERK, in PDAC GEM resistance, which will provide novel therapeutic targets for PDAC treatment.

From molecular pathogenesis to therapy: Unraveling non-coding RNAs/DNMT3A axis in human cancers

Cancer is a comprehensive classification encompassing more than 100 forms of malignancies that manifest in diverse tissues within the human body. Recent studies have provided evidence that aberrant epigenetic modifications are pivotal indicators of cancer. Epigenetics encapsulates DNA methyltransferases as a crucial class of modifiers. DNMTs, including DNMT3A, assume central roles in DNA methylation processes that orchestrate normal biological functions, such as gene transcription, predominantly in mammals. Typically, deviations in DNMT3A function engender distortions in factors that drive tumor growth and progression, thereby exacerbating the malignant phenotype of tumors. Consequently, such abnormalities pose significant challenges in cancer therapy because they impede treatment efficacy. Non-coding RNAs (ncRNAs) represent a group of RNA molecules that cannot encode functional proteins. Recent investigation attests to the crucial significance of regulatory ncRNAs in epigenetic regulation. Notably, recent reports have illuminated the complex interplay between ncRNA expression and epigenetic regulatory machinery, including DNMT3A, particularly in cancer. Recent findings have demonstrated that miRNAs, namely miR-770-5p, miR-101, and miR-145 exhibit the capability to target DNMT3A directly, and their aberration is implicated in diverse cellular abnormalities that predispose to cancer development. This review aims to articulate the interplay between DNMT3A and the ncRNAs, focusing on its impact on the development and progression of cancer, cancer therapy resistance, cancer stem cells, and prognosis. Importantly, the emergence of such reports that suggest a connection between DNMT3A and ncRNAs in several cancers indicates that this connecting axis offers a valuable target with significant therapeutic potential that might be exploited for cancer management.

YB-1 Targeted by miR-509-3-5p Affects Migration and Invasion of Triple‑Negative Breast Cancer by Regulating Cellular Epithelial‑Mesenchymal Transition

The epithelial-mesenchymal transition (EMT) process is closely linked to metastasis of breast cancer. This article elucidates the role of Y-box binding protein-1 (YB-1) on the migration and invasion of triple-negative breast cancer (TNBC) cells by regulating EMT, and the related mechanism. The expression data of YB-1 and miR-509-3-5p in TNBC samples and normal samples were downloaded from the GEO database. The proliferation, migration, invasion, and EMT of TNBC cells were detected by CCK-8 assay, colony formation assay, wound-healing assay, transwell assay, and immunoblotting analyses. The targeted binding of YB-1 and miR-509-3-5p was validated by luciferase reporter experiment. A xenograft mouse model was constructed to investigate the influence of the miR-509-3-5p/YB-1 axis on TNBC tumor growth in vivo. YB-1 was overexpressed, while miR-509-3-5p was underexpressed in TNBC tumor tissues and various cell lines. Silencing YB-1 depressed cell viability, proliferation, motility, and EMT in vitro, and miR-509-3-5p upregulation exerted the same effects. YB-1 was targeted by miR-509-3-5p. The suppressive effects on the phenotypes of TNBC cells caused by overexpressed miR-509-3-5p were attenuated by YB-1 upregulation. In addition, miR-509-3-5p overexpression restrained TNBC tumor growth and downregulated the YB-1-mediated EMT process in vivo. YB-1 targeted by miR-509-3-5p affects motility of TNBC cells by regulating cellular EMT.

Regeneration and anti-inflammatory effects of stem cells and their extracellular vesicles in gynecological diseases

There are many gynecological diseases, among which breast cancer (BC), cervical cancer (CC), endometriosis (EMs), and polycystic ovary syndrome (PCOS) are common and difficult to cure. Stem cells (SCs) are a focus of regenerative medicine. They are commonly used to treat organ damage and difficult diseases because of their potential for self-renewal and multidirectional differentiation. SCs are also commonly used for difficult-to-treat gynecological diseases because of their strong directional differentiation ability with unlimited possibilities, their tendency to adhere to the diseased tissue site, and their use as carriers for drug delivery. SCs can produce exosomes in a paracrine manner. Exosomes can be produced in large quantities and have the advantage of easy storage. Their safety and efficacy are superior to those of SCs, which have considerable potential in gynecological treatment, such as inhibiting endometrial senescence, promoting vascular reconstruction, and improving anti-inflammatory and immune functions. In this paper, we review the mechanisms of the regenerative and anti-inflammatory capacity of SCs and exosomes in incurable gynecological diseases and the current progress in their application in genetic engineering to provide a foundation for further research.

Emerging roles of interactions between ncRNAs and other epigenetic modifications in breast cancer

Up till the present moment, breast cancer is still the leading cause of cancer-related death in women worldwide. Although the treatment methods and protocols for breast cancer are constantly improving, the long-term prognosis of patients is still not optimistic due to the complex heterogeneity of the disease, multi-organ metastasis, chemotherapy and radiotherapy resistance. As a newly discovered class of non-coding RNAs, ncRNAs play an important role in various cancers. Especially in breast cancer, lncRNAs have received extensive attention and have been confirmed to regulate cancer progression through a variety of pathways. Meanwhile, the study of epigenetic modification, including DNA methylation, RNA methylation and histone modification, has developed rapidly in recent years, which has greatly promoted the attention to the important role of non-coding RNAs in breast cancer. In this review, we carefully and comprehensively describe the interactions between several major classes of epigenetic modifications and ncRNAs, as well as their different subsequent biological effects, and discuss their potential for practical clinical applications.

The important role of miR-770 as a novel potential diagnostic and therapeutic target for human cancer and other diseases

MicroRNA-770 (miR-770) is an RNA gene, located on chromosome 14q32.2. It has important effects on the pathobiology of cancers and other human diseases. It is known to be a tumor suppressor in breast cancer, ovarian cancer, gastric cancer, non-small cell lung cancer, prostate cancer, and glioblastoma. In colorectal adenocarcinoma and oral squamous cell carcinoma, miR-770 is regarded as an oncogenic miRNA. In several disorders, miR-770 dysregulation has been recognized as a potential biomarker for disease diagnosis and prognosis. Dysregulation of miR-770 has also been demonstrated in non-malignant human disorders, including Alzheimer's disease, dilated cardiomyopathy, diabetic nephropathy, Hirschsprung's disease, osteoarthritis, silicosis, and type 2 diabetes mellitus. In the current review, we have obtained the miR-770 target genes, ontology, and related pathways. We have also provided a comprehensive review of miR-770 in both malignant and non-malignant disorders and explained its possible therapeutic implications.

Epigenetic regulation of epithelial-mesenchymal transition during cancer development

Epithelial-mesenchymal transition (EMT) plays essential roles in promoting malignant transformation of epithelial cells, leading to cancer progression and metastasis. During EMT-induced cancer development, a wide variety of genes are dramatically modified, especially down-regulation of epithelial-related genes and up-regulation of mesenchymal-related genes. Expression of other EMT-related genes is also modified during the carcinogenic process. Especially, epigenetic modifications are observed in the EMT-related genes, indicating their involvement in cancer development. Mechanically, epigenetic modifications of histone, DNA, mRNA and non-coding RNA stably change the EMT-related gene expression at transcription and translation levels. Herein, we summarize current knowledge on epigenetic regulatory mechanisms observed in EMT process relate to cancer development in humans. The better understanding of epigenetic regulation of EMT during cancer development may lead to improvement of drug design and preventive strategies in cancer therapy.

The Mechanism of DNA Methylation and miRNA in Breast Cancer

Breast cancer is the most prevalent cancer in the world. Currently, the main treatments for breast cancer are radiotherapy, chemotherapy, targeted therapy and surgery. The treatment measures for breast cancer depend on the molecular subtype. Thus, the exploration of the underlying molecular mechanisms and therapeutic targets for breast cancer remains a hotspot in research. In breast cancer, a high level of expression of DNMTs is highly correlated with poor prognosis, that is, the abnormal methylation of tumor suppressor genes usually promotes tumorigenesis and progression. MiRNAs, as non-coding RNAs, have been identified to play key roles in breast cancer. The aberrant methylation of miRNAs could lead to drug resistance during the aforementioned treatment. Therefore, the regulation of miRNA methylation might serve as a therapeutic target in breast cancer. In this paper, we reviewed studies on the regulatory mechanisms of miRNA and DNA methylation in breast cancer from the last decade, focusing on the promoter region of tumor suppressor miRNAs methylated by DNMTs and the highly expressed oncogenic miRNAs inhibited by DNMTs or activating TETs.

NONHSAT021545/miR-330-3p/EREG: A Cooperative Axis in Breast Cancer Prognosis and Treatment

Lymphatic metastasis is the most common form in breast cancer (BC) progression. Previously, we observed that lnc045874, a most conservative homology of Homo Sapiens NONHSAT021545 (lnc021545), miR-330-3p, and EREG may have some effects in mouse hepatocarcinoma cell lines with different lymphatic metastasis potentials. Through data from TCGA and GEO database analysis, we speculated that miR-330-3p might be a tumor promoter, while EREG could be a tumor suppressor in BC. MiR-330-3p was upregulated, while lnc021545 and EREG were downregulated in 50 BC tissues. MiR-330-3p advanced the metastatic behaviors of BC cells, whereas lnc021545 and EREG resulted in the opposite effects. The three molecules' expressions were correlated respectively and showed that miR-330-3p targeted lnc021545 and EREG to affect their expressions. Lnc021545/miR-330-3p axis affected BC metastasis by regulating EREG in epithelial-to-mesenchymal transition. In 50 BC patients, these three molecules and their cooperation are associated with aggressive tumor phenotypes, patient outcomes, and trastuzumab therapy. We finally discovered that lnc021545, miR-330-3p, and EREG formed a multi-gene co-regulation system that affected the metastasis of BC and the cooperation reflects the synergistic effects of the three molecules, recommending that their cooperation may provide a more accurate index for anti-metastasis therapeutic and prognostic evaluation of BC.

miR-142-3p improves paclitaxel sensitivity in resistant breast cancer by inhibiting autophagy through the GNB2-AKT-mTOR Pathway

Breast cancer has overtaken lung cancer as the most prevalent cancer worldwide. The development of advanced drug resistance inhibits the efficacy of paclitaxel(PTX)as a first-line chemotherapeutic agent for breast cancer. Autophagy and microRNAs (miRNAs) play a key role in chemoresistance. This study investigated the miR-142-3p effect on PTX resistance by regulating autophagy. A PTX-resistant breast cancer cell line was constructed, and miR-142-3p and G protein beta polypeptide 2 (GNB2) were filtered out using RNA sequencing and protein microarray analysis. The study revealed that miR-142-3p expression was lower in drug-resistant cells compared parental cells. Higher miR-142-3p expression inhibited the viability, migration, and autophagic flux of drug-resistant cells, while promoting apoptosis and sensitivity to PTX treatment. Mechanistically, miR-142-3p was found to amend PTX resistance by targeting GNB2, further revealing that the knockdown of GNB2 expression could activate the AKT-mTOR pathway. This study suggests that GNB2 is an essential target for miR-142-3p to restrain autophagy, providing a new reference value for improving breast cancer PTX treatment.

Crosstalk between Methylation and ncRNAs in Breast Cancer: Therapeutic and Diagnostic Implications

Breast cancer, as a highly heterogeneous malignant tumor, is one of the primary causes of death among females worldwide. The etiology of breast cancer involves aberrant epigenetic mechanisms and abnormal expression of certain non-coding RNA (ncRNAs). DNA methylation, N6-methyladenosine(m6A), and histone methylation are widely explored epigenetic regulation types in breast cancer. ncRNAs are a group of unique RNA transcripts, mainly including microRNA (miRNAs), long non-coding RNA (lncRNAs), circular RNA (circRNAs), small interfering RNA (siRNAs), piwi-interacting RNA (piRNAs), etc. Different types of methylation and ncRNAs mutually regulate and interact to form intricate networks to mediate precisely breast cancer genesis. In this review, we elaborate on the crosstalk between major methylation modifications and ncRNAs and discuss the role of their interaction in promoting breast cancer oncogenesis. This review can provide novel insights into establishing a new diagnostic marker system on methylation patterns of ncRNAs and therapeutic perspectives of combining ncRNA oligonucleotides and phytochemical drugs for breast cancer therapy.

Concise Synthesis of Tunicamycin V and Discovery of a Cytostatic DPAGT1 Inhibitor

A short total synthesis of tunicamycin V (1), a non-selective phosphotransferase inhibitor, is achieved via a Büchner-Curtius-Schlotterbeck type reaction. Tunicamycin V can be synthesized in 15 chemical steps from D-galactal with 21 % overall yield. The established synthetic scheme is operationally very simple and flexible to introduce building blocks of interest. The inhibitory activity of one of the designed analogues 28 against human dolichyl-phosphate N-acetylglucosaminephosphotransferase 1 (DPAGT1) is 12.5 times greater than 1. While tunicamycins are cytotoxic molecules with a low selectivity, the novel analogue 28 displays selective cytostatic activity against breast cancer cell lines including a triple-negative breast cancer.

DNMT3A and DNMT3B in Breast Tumorigenesis and Potential Therapy

Breast cancer has become a leading cause of cancer-related deaths in women worldwide. DNA methylation has been revealed to play an enormously important role in the development and progression of breast cancer. DNA methylation is regulated by DNA methyltransferases (DNMTs), including DNMT1, DNMT2, and DNMT3. DNMT3 family has three members: DNMT3A, DNMT3B, and DNMT3L. The roles and functions of DNMT1 in breast cancer have been well reviewed. In this article, the roles of DNMT3A and DNMT3B in breast tumorigenesis and development are reviewed. We also discuss the SNP and mutations of DNMT3A and DNMT3B in breast cancer. In addition, we summarize how DNMT3A and DNMT3B are regulated by non-coding RNAs and signaling pathways in breast cancer, and targeting the expression levels of DNMT3A and DNMT3B may be a promising therapeutic approach for breast cancer. This review will provide reference for further studies on the biological functions and molecular mechanisms of DNMT3A and DNMT3B in breast cancer.

Potential epigenetic modifications implicated in triple- to quadruple-negative breast cancer transition: a review

Current research on triple-negative breast cancer (TNBC) has resulted in delineation into the quadruple-negative breast cancer (QNBC) subgroup. Epigenetic modifications such as DNA methylation, histone posttranslational modifications and associated changes in chromatin architecture have been implicated in breast cancer pathogenesis. Herein, the authors highlight genes with observed epigenetic modifications that are associated with more aggressive TNBC/QNBC pathogenesis and possible interventions. Advanced literature searches were done on PubMed/MEDLINE, Scopus and Google Scholar. The results suggest that nine epigenetically altered genes/differentially expressed proteins in addition to the downregulated androgen receptor are associated with TNBC aggressiveness and could be implicated in the TNBC to QNBC transition. Thus, restoring the normal expression of these genes via epigenetic reprogramming could be therapeutically beneficial to TNBC and QNBC patients.

The mechanism of action of Fangji Huangqi Decoction on epithelial-mesenchymal transition in breast cancer using high-throughput next-generation sequencing and network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Fangji Huangqi Decoction (FHD) is widely used in traditional Chinese medicine (TCM). FHD has been hypothesized to inhibit the epithelial-mesenchymal transition (EMT) process, which may positively impact breast cancer prevention and treatment. However, its exact mechanism of action is still unknown.

AIM OF THE STUDY

This study aimed to screen potential targets of FHD for the treatment of EMT in breast cancer through network pharmacology, and to verify their therapeutic effects in vitro experiments and high-throughput second-generation sequencing.

MATERIALS AND METHODS

The data sets of effective components and targets of FHD were established through the Traditional Chinese Medicine Systems Pharmacology database. The GeneCards and OMIM databases were used to establish breast cancer-related target datasets, which were then matched with the TCM target data. The interaction between key target proteins was analyzed using the STRING database; the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were used to identify the associated biological processes and enriched signal pathways, respectively. The active ingredient disease target network was analyzed using Cytoscape. Finally, next generation sequencing was used to verify the related pathways of FHD intervention in EMT in breast cancer. High-content screening was used to identify the genes/pathways affected by FHD. MDA-MB-231 and HCC-1937 breast cancer cell lines were used to evaluate the impact of FHD on migration, invasion, and EMT.

RESULTS

Eighty possible significant targets were identified for the treatment of breast cancer EMT with FHD; GO and KEGG were used to identify 173 cell biological processes associated with breast cancer (P < 0.05), including the NF-κB and PI3K-Akt signaling pathways. The high-throughput sequencing and network pharmacology results were highly consistent. The migration and invasion ability of MDA-MB-231 cells was reduced and their EMT status could be reversed by DSHR2 knockdown. The results of morphology and scratch assays showed that FHD could improve the EMT status of HCC-1973.

CONCLUSIONS

This study provides more evidence to support the clinical application of FHD, which has reliable interventional effects on breast cancer EMT. Its therapeutic effects may involve a multi-target, multi-pathway, and multi-mechanism effect.

Comparative mRNA/micro-RNA co-expression network drives melanomagenesis by promoting epithelial-mesenchymal transition and vasculogenic mimicry signaling

This study aimed to identify a novel disease-associated differentially co-expressed mRNA-microRNA (miRNA) that is associated with vasculogenic mimicry (VM) and epithelial-to-mesenchymal transition (EMT) network at different stages of melanoma. By applying weighted gene co-expression network analysis, we constructed a VM+EMT biological network with the available microarray dataset downloaded from a public database. Quantitative real-time PCR, immunohistochemical staining, and CD31-periodic acid solution dual staining were performed to confirm the expression of genes associated with EMT and VM formation in subjects with malignant melanoma (n = 18) and primary melanoma (n = 13) and in healthy subjects (n = 10). Our findings suggested that phosphatidylserine-specific phospholipase A1-alpha (PLA1A) and dermokine (DMKN) genes function as oncogenes that trigger VM and EMT processes during melanomagenesis on interaction with miR-370, miR-563, and miR-770-5p. PLA1A and DMKN genes can be considered potential VM+EMT network-based diagnostic biomarkers for distinguishing between melanoma patients. We postulate that a network with altered PLA1A/miR-563 and DMNK/miR-770-5p/miR-370 may contribute to melanomagenesis by triggering the EMT signaling pathway and VM formation. This study provides a potentially valuable approach for the early diagnosis and prognosis of melanoma progression.

Sesamol Epigenetically Induces Estrogen Receptor α Re-expression by Upregulating miR-370-3p in Estrogen Receptor α-Negative Breast Cancer

Due to lack of estrogen receptor α (ERα, gene name: ESR1), ERα-negative breast carcinoma is insensitive to endocrine therapy, and restoration of ERα has become a promising strategy for ERα-negative breast cancer treatment. Sesamol, a naturally occurring phenolic compound, is usually extracted from sesame seeds. Previous investigations have unmasked its anti-oxidant and anti-inflammation properties. In this study, sesamol induced ERα functional re-expression followed by upregulation of its downstream pS2 and GREB1 genes in ERα-negative breast carcinoma. Moreover, it endowed responsiveness of ERα-negative breast carcinoma to the endocrine treatment drug 4-hydroxytamoxifen without influencing the viability of normal human umbilical vein endothelial cells. Mechanistically, sesamol induced ESR1 gene promoter demethylation by downregulating the expression of the DNA methyltransferases DNMT3A and DNMT3B, without affecting DNMT1. Moreover, the non-coding RNA miR-370-3p directly targeted DNMT3A and DNMT3B mRNA, and its expression increased upon treatment with sesamol. Artificial abrogation of miR-370-3p expression with an antagomir abolished the inhibition of DNMT3A and DNMT3B expression by sesamol, resulting in a fallback in ERα reactivation. In mice, sesamol significantly induced ERα re-expression via miR-370-3p-mediated downregulation of DNMT3A and DNMT3B. Sesamol may be a safe and effective option for clinical adjuvant therapy in patients with ERα-negative breast cancer.