MiR-424-3p suppresses galectin-3 expression and sensitizes ovarian cancer cells to cisplatin

Chemopreventive and therapeutic effects of Hippophae rhamnoides L. fruit peels evaluated in preclinical models of breast carcinoma

Background

Cancer remains a major global health challenge, necessitating innovative prevention and treatment approaches. Certain plants, adapted to specific environments, may exhibit bioactive properties with potential anticancer applications.

Hypothesis

Seaberry (Hippophae rhamnoides L.) fruit peels may exert anticancer effects in breast carcinoma (BC) models through the additive or synergistic actions of their unique secondary metabolites.

Methods

H. rhamnoides fruit peel extracts were analyzed using the LC-DAD-MS and LC-DAD techniques to profile the content of carotenoids and flavonoids, respectively. The preclinical study evaluated seaberry fruit peel extracts in BC models: (1) a syngeneic 4T1 mouse breast adenocarcinoma model (triple-negative), (2) a rat model of chemically induced mammary carcinogenesis, and (3) in vitro studies with MCF-7 (hormone receptor-positive) and MDA-MB-231 (triple-negative) BC cell lines.

Results

LC-DAD-MS and LC-DAD analyses identified dominant metabolites, including isorhamnetin, quercetin glycosides, kaempferol glycosides, catechin, zeaxanthin, and lutein. In the 4T1 mouse model, seaberry treatment resulted in a significant, dose-dependent reduction in tumor volume (43% and 48% compared to controls) and a decrease in the mitotic activity index. Serum cytokine analysis showed dose-dependent reductions in IL-6, IL-10, and TNF-α. In the rat chemopreventive model, high-dose seaberry improved cancer prognosis by reducing the ratio of poorly differentiated tumors and increasing caspase-3 and Bax expression while decreasing Ki-67 and malondialdehyde levels. Both treatment doses elevated the Bax/Bcl-2 ratio and reduced the expression of cancer stem cell markers CD44, EpCam, and VEGF compared to controls. Epigenetic analyses revealed histone modifications (H4K16ac, H4K20me3) and altered methylation of tumor-suppressor genes (PITX2, RASSF1, PTEN, TIMP3). Microarray analysis (758 miRNAs) identified beneficial changes in nine oncogenic/tumor-suppressive miRNAs, including miR-10a-5p, miR-322-5p, miR-450a-5p, miR-142-5p, miR-148b-3p, miR-1839-3p, miR-18a-5p, miR-1949, and miR-347. In vitro, ethanolic seaberry extract conferred partial resistance to cisplatin-induced cytotoxicity in MCF-7 and MDA-MB-231 cells at IC50 concentrations.

Conclusion

This study of H. rhamnoides in rodent BC models shows promising data but requires rigorous, long-term validation. Integrating plant-based nutraceuticals into oncology necessitates precise cancer-type profiling and patient stratification for effective personalized treatments.

Overexpression of miR‑424‑5p reduces cisplatin resistance by downregulating SMURF1 in gastric cancer

Chemoresistance is a major obstacle in the treatment of gastric cancer (GC). Notably, aberrant expression of microRNAs (miRs) is closely related to tumor development and progression. In the present study, the role of miR-424-5p in the chemoresistance of GC was investigated. Reverse transcription-quantitative PCR was used to detect the expression levels of miR-424-5p in tissues and different cell lines. Cell viability and apoptosis were detected via a Cell Counting Kit-8 assay, western blotting and flow cytometry. The targeting relationship between miR-424-5p and SMAD-specific E3 ubiquitin protein ligase 1 (SMURF1) was verified via dual-luciferase reporter assays and the molecular mechanism was investigated by western blotting. The results revealed that miR-424-5p was expressed at low levels in GC tissues and cell lines, and that low miR-424-5p expression was associated with poor N stage and worse prognosis, especially in patients who received adjuvant chemotherapy. Further experiments revealed that the overexpression of miR-424-5p reduced cisplatin (CDDP) resistance and promoted GC cell apoptosis, whereas inhibiting miR-424-5p had the opposite effect. Mechanistically, it was found that miR-424-5p downregulated the expression of SMURF1 to regulate the expression of ING2 and p53, thereby modulating CDDP resistance in GC. In summary, the present study demonstrated that miR-424-5p may serve an important regulatory role in CDDP resistance in GC, and could be a potential diagnostic biomarker and therapeutic target for GC chemoresistance.

MicroRNA‑mediated approaches in ovarian cancer therapy: A comprehensive systematic review

Ovarian cancer (OC) poses a significant health risk to women worldwide, with late diagnoses and chemotherapy resistance leading to high mortality rates. Despite several histological subtypes, the primary challenge remains the subtle nature of its symptoms, resulting in advanced-stage diagnosis and reduced treatment success rates. With platinum-based therapies showing relative efficacy but limited survival enhancements, the emergence of chemotherapy resistance during recurrence remains a critical obstacle. Precision medicine development has aimed to address these challenges in the context of the molecular diversity of OC. The present review explored the landscape of microRNA (miRNA)-mediated approaches in OC treatment. miRNAs have emerged as regulators of gene expression, serving as both oncogenes and tumor suppressors in OC. Dysregulated miRNAs are associated with disease progression and chemotherapy resistance, underscoring their significance in diagnosis and tailored treatment strategies. The present review extracted 295 publications from the PUBMED database. Out of the 73 eligible studies, 55 miRNAs were assessed. A total of three of these miRNAs were not associated with any disease or cancer, whilst eight were associated with OC, albeit also associated with other diseases. The present review encompassed three dimensions: i) The role of miRNAs in treatment efficacy; ii) the use of miRNAs to enhance therapy outcomes; and iii) adjunctive strategies for improved treatment results. Furthermore, it offered insights into potential avenues for improving OC treatment using miRNA-based approaches.

Uncovering miRNA-mRNA Regulatory Networks Related to Olaparib Resistance and Resensitization of BRCA2MUT Ovarian Cancer PEO1-OR Cells with the ATR/CHK1 Pathway Inhibitors

Resistance to olaparib is the major obstacle in targeted therapy for ovarian cancer (OC) with poly(ADP-ribose) polymerase inhibitors (PARPis), prompting studies on novel combination therapies to enhance olaparib efficacy. Despite identifying various mechanisms, understanding how OC cells acquire PARPi resistance remains incomplete. This study investigated microRNA (miRNA) expression in olaparib-sensitive (PEO1, PEO4) and previously established olaparib-resistant OC cell lines (PEO1-OR) using high-throughput RT-qPCR and bioinformatic analyses. The role of miRNAs was explored regarding acquired resistance and resensitization with the ATR/CHK1 pathway inhibitors. Differentially expressed miRNAs were used to construct miRNA-mRNA regulatory networks and perform functional enrichment analyses for target genes with miRNet 2.0. TCGA-OV dataset was analyzed to explore the prognostic value of selected miRNAs and target genes in clinical samples. We identified potential processes associated with olaparib resistance, including cell proliferation, migration, cell cycle, and growth factor signaling. Resensitized PEO1-OR cells were enriched in growth factor signaling via PDGF, EGFR, FGFR1, VEGFR2, and TGFβR, regulation of the cell cycle via the G2/M checkpoint, and caspase-mediated apoptosis. Antibody microarray analysis confirmed dysregulated growth factor expression. The addition of the ATR/CHK1 pathway inhibitors to olaparib downregulated FGF4, FGF6, NT-4, PLGF, and TGFβ1 exclusively in PEO1-OR cells. Survival and differential expression analyses for serous OC patients revealed prognostic miRNAs likely associated with olaparib resistance (miR-99b-5p, miR-424-3p, and miR-505-5p) and resensitization to olaparib (miR-324-5p and miR-424-3p). Essential miRNA-mRNA interactions were reconstructed based on prognostic miRNAs and target genes. In conclusion, our data highlight distinct miRNA profiles in olaparib-sensitive and olaparib-resistant cells, offering molecular insights into overcoming resistance with the ATR/CHK1 inhibitors in OC. Moreover, some miRNAs might serve as potential predictive signature molecules of resistance and therapeutic response.

Cigarette smoke-induced galectin-3 as a diagnostic biomarker and therapeutic target in lung tissue remodeling

Galectin-3 (Gal-3), a multifunctional carbohydrate-binding lectin, has emerged as a key player in various biological processes including inflammation, cancer, cardiovascular diseases and fibrotic disorders, however it remains unclear if Gal-3 is a bystander or drives lung tissue remodeling (LTR). Persistent exposure to cigarette smoke (CS) is the leading cause of oxidative and inflammatory damage to the lung tissues. CS-induced pathological increase in Gal-3 expression has been implicated in the pathogenesis of various respiratory conditions, such as chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), and lung cancer. We and others have reported that CS induces Gal-3 synthesis and secretion, which modulates the pathological signaling pathways in lung epithelial cells implicating Gal-3 as a novel diagnostic marker and a factor driving LTR in CS-exposed lungs. Therefore, pharmacological interventions targeting Gal-3 and its upstream and downstream signaling pathways can help combat CS-induced LTR. Excitingly, preclinical models have demonstrated the efficacy of interventions such as Gal-3 expression inhibition, Gal-3 receptor blockade, and signaling pathways modulation open up promising avenues for future therapeutic interventions. Furthermore, targeting extracellular vesicles-mediated Gal-3 release and the potential of microRNA-based therapy are emerging as novel therapeutic approaches in CS-induced LTR and have been discussed in this article.

Role of miR-424 in the carcinogenesis

Recent studies have revealed the impact of microRNAs (miRNAs) in the carcinogenic process. miR-424 is a miRNA whose role in this process is being to be identified. Experiments in the ovarian cancer, cervical cancer, hepatocellular carcinoma, neuroblastoma, breast cancer, osteosarcoma, intrahepatic cholangiocarcinoma, prostate cancer, endometrial cancer, non-small cell lung cancer, hemangioma and gastric cancer have reported down-regulation of miR-424. On the other hand, this miRNA has been found to be up-regulated in melanoma, laryngeal and esophageal squamous cell carcinomas, glioma, multiple myeloma and thyroid cancer. Expression of this miRNA is regulated by methylation status of its promoter. Besides, LINC00641, CCAT2, PVT1, LIN00657, LINC00511 and NNT-AS1 are among lncRNAs that act as molecular sponges for miR-424, thus regulating its expression. Moreover, several members of SNHG family of lncRNAs have been found to regulate expression of miR-424. This miRNA is also involved in the regulation of E2F transcription factors. The current review aims at summarization of the role of miR-424 in the process of cancer evolution and its impact on clinical outcome of patients in order to find appropriate markers for malignancies.

The Role of microRNAs in Hepatocellular Cancer: A Narrative Review Focused on Tumor Microenvironment and Drug Resistance

Globally, hepatic cancer ranks fourth in terms of cancer-related mortality and is the sixth most frequent kind of cancer. Around 80% of liver cancers are hepatocellular carcinomas (HCC), which are the leading cause of cancer death. It is well known that HCC may develop resistance to the available chemotherapy treatments very fast. One of the biggest obstacles in providing cancer patients with appropriate care is drug resistance. According to reports, more than 90% of cancer-specific fatalities are caused by treatment resistance. By binding to the 3'-untranslated region of target messenger RNAs (mRNAs), microRNAs (miRNAs), a group of noncoding RNAs which are around 17 to 25 nucleotides long, regulate target gene expression. Moreover, they play role in the control of signaling pathways, cell proliferation, and cell death. As a result, miRNAs play an important role in the microenvironment of HCC by changing immune phenotypes, hypoxic conditions, and acidification, as well as angiogenesis and extracellular matrix components. Moreover, changes in miRNA levels in HCC can effectively resist cancer cells to chemotherapy by affecting various cellular processes such as autophagy, apoptosis, and membrane transporter activity. In the current work, we narratively reviewed the role of miRNAs in HCC, with a special focus on tumor microenvironment and drug resistance.

Exosomes Derived from E2F1-/- Adipose-Derived Stem Cells Promote Skin Wound Healing via miR-130b-5p/TGFBR3 Axis

Background

Skin wound is a widespread health problem and brings extraordinary burdens to patients. Exosomes derived from adipose-derived stem cells (ADSC-Exos) are considered promising strategies for repairing skin wounds. E2F1 is a member of the E2F family of transcription factors involved in cell growth and apoptosis. E2F1 deficiency in mice enhances wound healing by improving collagen deposition and angiogenesis. Additionally, E2F1 can regulate the transcription and paracrine activity of multiple miRNAs, which will inevitably reshape the paracrine expression profile of ADSC-Exos. This study aimed to investigate the impact of transcription factor E2F1 deficiency on the functions of ADSC-Exos in promoting wound healing.

Methods

First, we obtained ADSCs from subcutaneous adipose tissues of WT and E2F1-/- C57BL/6 mice and separated their exosomes, denoted as ADSCWT-Exos and ADSCE2F1-/--Exos. The wound healing effects of ADSCWT-Exos and ADSCE2F1-/--Exos in full-thickness skin wound models were investigated by wound images, H&E staining, and immunohistochemical staining. For the in vitro study, the abilities of ADSCWT-Exos and ADSCE2F1-/--Exos to promote cell activities, collagen formation, and angiogenesis were evaluated. The potential mechanism by which ADSCE2F1-/--Exos promote wound healing was determined by miRNA sequencing, ChIP‒qPCR, and dual-luciferase assays.

Results

ADSCE2F1-/--Exos accelerated wound healing by promoting collagen formation and angiogenesis. As a result, compared with the lower wound healing rate of 30.5% within 7 days in the control group and 42.3% in the ADSCWT-Exo group, ADSCE2F1-/--Exos significantly increased the wound healing rate to 72.5%. In vitro, ADSCE2F1-/--Exos activated the function of fibroblasts and vascular endothelial cells. The loss of E2F1 promoted miR-130b-5p expression in ADSCE2F1-/--Exos through transcriptional regulation. MiRNA high-throughput sequencing identified 12 differently expressed miRNAs between ADSCE2F1-/- and ADSCWT. ADSCE2F1-/--Exos enhanced fibroblast activities via the miR-130b-5p/TGFBR3 axis and TGF-β activation.

Conclusion

Our results indicated that ADSCE2F1-/--Exos effectively promoted wound healing by regulating the miR-130b-5p/TGFBR3 axis, thus providing a novel strategy of gene-engineered stem cell exosomes for accelerating wound healing.

miR-424-3p promotes metastasis of hepatocellular carcinoma via targeting the SRF-STAT1/2 axis

Although emerging evidence has established the roles of miRNAs in hepatocellular carcinoma (HCC), the global functional implication of miRNAs in this malignancy remains largely uncharacterized. Here, we aim to systematically identify novel miRNAs involved in HCC and clarify the function and mechanism of specific novel candidate miRNA(s) in this malignancy. Through an integrative omics approach, we identified ten HCC-associated functional modules and a collection of candidate miRNAs. Among them, we demonstrated that miR-424-3p, exhibiting strong associations with extracellular matrix (ECM), promotes HCC cells migration and invasion in vitro and facilitates HCC metastasis in vivo. We further demonstrated that SRF is a direct functional target of miR-424-3p, and is required for the oncogenic activity of miR-424-3p. Finally, we found that miR-424-3p reduces the interferon pathway by attenuating the transactivation of SRF on STAT1/2 and IRF9 genes, which in turn enhances the matrix metalloproteinases (MMPs)-mediated ECM remodeling. This study provides comprehensive functional relevance of miRNAs in HCC by an integrative omics analysis, and further clarifies that miR-424-3p in ECM functional module plays an oncogenic role via reducing the SRF-STAT1/2 axis in this malignancy.

Galectin-3's Complex Interactions in Pancreatic Ductal Adenocarcinoma: From Cellular Signaling to Therapeutic Potential

Galectin-3 (Gal-3) plays a multifaceted role in the development, progression, and prognosis of pancreatic ductal adenocarcinoma (PDAC). This review offers a comprehensive examination of its expression in PDAC, its interaction with various immune cells, signaling pathways, effects on apoptosis, and therapeutic resistance. Additionally, the prognostic significance of serum levels of Gal-3 is discussed, providing insights into its potential utilization as a biomarker. Critical analysis is also extended to the inhibitors of Gal-3 and their potential therapeutic applications in PDAC, offering new avenues for targeted treatments. The intricate nature of Gal-3's role in PDAC reveals a complex landscape that demands a nuanced understanding for potential therapeutic interventions and monitoring.

Apoptosis and heart failure: The role of non-coding RNAs and exosomal non-coding RNAs

Heart failure is a condition that affects the cardio vascular system and occurs if the heart cannot adequately pump the oxygen and blood to the body. Myocardial infarction, reperfusion injury, and this disease is the only a few examples of the numerous cardiovascular illnesses that are impacted by the closely controlled cell deletion process known as apoptosis. Attention has been paid to the creation of alternative diagnostic and treatment modalities for the condition. Recent evidences have shown that some non-coding RNAs (ncRNAs) influence the stability of proteins, control of transcription factors, and HF apoptosis through a variety of methods. Exosomes make a significant paracrine contribution to the regulation of illnesses as well as to the communication between nearby and distant organs. However, it has not yet been determined whether exosomes regulate the cardiomyocyte-tumor cell interaction in ischemia HF to limit the vulnerability of malignancy to ferroptosis. Here, we list the numerous ncRNAs in HF that are connected to apoptosis. In addition, we emphasize the significance of exosomal ncRNAs in the HF.

Blood Plasma Small Non-Coding RNAs as Diagnostic Molecules for the Progesterone-Receptor-Negative Phenotype of Serous Ovarian Tumors

The expression level of the progesterone receptor (PGR) plays a crucial role in determining the biological characteristics of serous ovarian carcinoma. Low PGR expression is associated with chemoresistance and a poorer outcome. In this study, our objective was to explore the relationship between tumor progesterone receptor levels and RNA profiles (miRNAs, piwiRNAs, and mRNAs) to understand their biological characteristics and behavior. To achieve this, we employed next-generation sequencing of small non-coding RNAs, quantitative RT-PCR, and immunohistochemistry to analyze both FFPE and frozen tumor samples, as well as blood plasma from patients with benign cystadenoma (BSC), serous borderline tumor (SBT), low-grade serous ovarian carcinoma (LGSOC), and high-grade serous ovarian carcinoma (HGSOC). Our findings revealed significant upregulation of MMP7 and MUC16, along with downregulation of PGR, in LGSOC and HGSOC compared to BSC. We observed significant correlations of PGR expression levels in tumor tissue with the contents of miR-199a-5p, miR-214-3p, miR-424-3p, miR-424-5p, and miR-125b-5p, which potentially target MUC16, MMP7, and MMP9, as well as with the tissue content of miR-16-5p, miR-17-5p, miR-20a-5p, and miR-93-5p, which are associated with the epithelial-mesenchymal transition (EMT) of cells. The levels of EMT-associated miRNAs were significantly correlated with the content of hsa_piR_022437, hsa_piR_009295, hsa_piR_020813, hsa_piR_004307, and hsa_piR_019914 in tumor tissues. We developed two optimal logistic regression models using the quantitation of hsa_piR_020813, miR-16-5p, and hsa_piR_022437 or hsa_piR_004307, hsa_piR_019914, and miR-93-5p in the tumor tissue, which exhibited a significant ability to diagnose the PGR-negative tumor phenotype with 93% sensitivity. Of particular interest, the blood plasma levels of miR-16-5p and hsa_piR_022437 could be used to diagnose the PGR-negative tumor phenotype with 86% sensitivity even before surgery and chemotherapy. This knowledge can help in choosing the most effective treatment strategy for this aggressive type of ovarian cancer, such as neoadjuvant chemotherapy followed by cytoreduction in combination with hyperthermic intraperitoneal chemotherapy and targeted therapy, thus enhancing the treatment's effectiveness and the patient's longevity.

Inhibition of galectins in cancer: Biological challenges for their clinical application

Galectins play relevant roles in tumor development, progression and metastasis. Accordingly, galectins are certainly enticing targets for medical intervention in cancer. To date, however, clinical trials based on galectin inhibitors reported inconclusive results. This review summarizes the galectin inhibitors currently being evaluated and discusses some of the biological challenges that need to be addressed to improve these strategies for the benefit of cancer patients.

The Mutual Relationship between Glycosylation and Non-Coding RNAs in Cancer and Other Physio-Pathological Conditions

Glycosylation, which consists of the enzymatic addition of sugars to proteins and lipids, is one of the most important post-co-synthetic modifications of these molecules, profoundly affecting their activity. Although the presence of carbohydrate chains is crucial for fine-tuning the interactions between cells and molecules, glycosylation is an intrinsically stochastic process regulated by the relative abundance of biosynthetic (glycosyltransferases) and catabolic (glycosidases) enzymes, as well as sugar carriers and other molecules. Non-coding RNAs, which include microRNAs, long non-coding RNAs and circRNAs, establish a complex network of reciprocally interacting molecules whose final goal is the regulation of mRNA expression. Likewise, these interactions are stochastically regulated by ncRNA abundance. Thus, while protein sequence is deterministically dictated by the DNA/RNA/protein axis, protein abundance and activity are regulated by two stochastic processes acting, respectively, before and after the biosynthesis of the protein axis. Consequently, the worlds of glycosylation and ncRNA are closely interconnected and mutually interacting. In this paper, we will extensively review the many faces of the ncRNA-glycosylation interplay in cancer and other physio-pathological conditions.

The Features of Immune Checkpoint Gene Regulation by microRNA in Cancer

Currently, the search for new promising tools of immunotherapy continues. In this regard, microRNAs (miRNAs) that influence immune checkpoint (IC) gene expression in tumor and T-cells and may be important regulators of immune cells are considered. MiRNAs regulate gene expression by blocking mRNA translation. An important feature of miRNA is its ability to affect the expression of several genes simultaneously, which corresponds to the trend toward the use of combination therapy. The article provides a list of miRNAs acting simultaneously on several ICs and miRNAs that, in addition to IC, can regulate the expression of targeted therapy genes. There is dependence of miRNA interactions with IC genes on the type of cancer. The analysis of the accumulated data demonstrates that only about 14% (95% CI: 9.8–20.1%) of the studied miRNAs regulate the expression of specific IC in more than one type of cancer. That is, there is tumor specificity in the miRNA action on ICs. A number of miRNAs demonstrated high efficiency in vitro and in vivo. This indicates the potential of miRNAs as promising agents for cancer immunotherapy. Additional studies of the miRNA–gene interaction features and the search for an optimal miRNA mimic structure are necessary.

The role of galectins‑1, 3, 7, 8 and 9 as potential diagnostic and therapeutic markers in ovarian cancer (Review)

The incidence of ovarian cancer is increasing, particularly throughout the highly developed countries, while this cancer type remains a major diagnostic and therapeutic challenge. The currently poorly recognized lectins called galectins have various roles in interactions occurring in the tumor microenvironment. Galectins are involved in tumor-associated processes, including the promotion of growth, adhesion, angiogenesis and survival of tumor cells. Results of research studies performed so far point to a complex role of galectins-1, 3, −7, −8 and −9 in carcinogenesis of ovarian cancer and elucidation of the mechanisms may contribute to novel forms of therapies targeting the proteins. In particular, it appears important to recognize the reasons for changes in expression of galectins. Galectins also appear to be a useful diagnostic and prognostic tool to evaluate tumor progression or the efficacy of therapies in patients with ovarian cancer, which requires further study.

MicroRNA as a Potential Therapeutic Molecule in Cancer

Small noncoding RNAs, as post-translational regulators of many target genes, are not only markers of neoplastic disease initiation and progression, but also markers of response to anticancer therapy. Hundreds of miRNAs have been identified as biomarkers of drug resistance, and many have demonstrated the potential to sensitize cancer cells to therapy. Their properties of modulating the response of cells to therapy have made them a promising target for overcoming drug resistance. Several methods have been developed for the delivery of miRNAs to cancer cells, including introducing synthetic miRNA mimics, DNA plasmids containing miRNAs, and small molecules that epigenetically alter endogenous miRNA expression. The results of studies in animal models and preclinical studies for solid cancers and hematological malignancies have confirmed the effectiveness of treatment protocols using microRNA. Nevertheless, the use of miRNAs in anticancer therapy is not without limitations, including the development of a stable nanoconstruct, delivery method choices, and biodistribution. The aim of this review was to summarize the role of miRNAs in cancer treatment and to present new therapeutic concepts for these molecules. Supporting anticancer therapy with microRNA molecules has been verified in numerous clinical trials, which shows great potential in the treatment of cancer.

Critical appraisal of epigenetic regulation of galectins in cancer

Galectins are defined as the glycan-binding protein containing either one or two carbohydrate-binding domains and participate in various biological functions such as developmental processes, vascularisation programs, cell migration, and immune-regulation and apoptosis. Galectins are also linked to many diseases, including cancer. They are widely spread in extracellular and intracellular spaces, and their altered expression in cancer leads to tumor progression, metastasis, angiogenesis and stemness through different signalling pathways. Promoter methylation, microRNA, and histone modification constitute the epigenetic changes that regulate galectin activity in cancer. Our review discusses the concept of epigenetics in cancer and how the aforementioned factors i.e., promoter methylation, histone modification, change in miRNAs expression affect the glycomic changes in malignancies.

Tumor Suppressor miRNA in Cancer Cells and the Tumor Microenvironment: Mechanism of Deregulation and Clinical Implications

MicroRNAs (miRNAs) are noncoding RNAs that have been identified as important posttranscriptional regulators of gene expression. miRNAs production is controlled at multiple levels, including transcriptional and posttranscriptional regulation. Extensive profiling studies have shown that the regulation of mature miRNAs expression plays a causal role in cancer development and progression. miRNAs have been identified to act as tumor suppressors (TS) or as oncogenes based on their modulating effect on the expression of their target genes. Upregulation of oncogenic miRNAs blocks TS genes and leads to tumor formation. In contrast, downregulation of miRNAs with TS function increases the translation of oncogenes. Several miRNAs exhibiting TS properties have been studied. In this review we focus on recent studies on the role of TS miRNAs in cancer cells and the tumor microenvironment (TME). Furthermore, we discuss how TS miRNA impacts the aggressiveness of cancer cells, with focus of the mechanism that regulate its expression. The study of the mechanisms of miRNA regulation in cancer cells and the TME may paved the way to understand its critical role in the development and progression of cancer and is likely to have important clinical implications in a near future. Finally, the potential roles of miRNAs as specific biomarkers for the diagnosis and the prognosis of cancer and the replacement of tumor suppressive miRNAs using miRNA mimics could be promising approaches for cancer therapy.

MicroRNAs as the critical regulators of Cisplatin resistance in ovarian cancer cells

BACKGROUND

Ovarian cancer (OC) is one of the leading causes of cancer related deaths among women. Due to the asymptomatic tumor progression and lack of efficient screening methods, majority of OC patients are diagnosed in advanced tumor stages. A combination of surgical resection and platinum based-therapy is the common treatment option for advanced OC patients. However, tumor relapse is observed in about 70% of cases due to the treatment failure. Cisplatin is widely used as an efficient first-line treatment option for OC; however cisplatin resistance is observed in a noticeable ratio of cases. Regarding, the severe cisplatin side effects, it is required to clarify the molecular biology of cisplatin resistance to improve the clinical outcomes of OC patients. Cisplatin resistance in OC is associated with abnormal drug transportation, increased detoxification, abnormal apoptosis, and abnormal DNA repair ability. MicroRNAs (miRNAs) are critical factors involved in cell proliferation, apoptosis, and chemo resistance. MiRNAs as non-invasive and more stable factors compared with mRNAs, can be introduced as efficient markers of cisplatin response in OC patients.

MAIN BODY

In present review, we have summarized all of the miRNAs that have been associated with cisplatin resistance in OC. We also categorized the miRNAs based on their targets to clarify their probable molecular mechanisms during cisplatin resistance in ovarian tumor cells.

CONCLUSIONS

It was observed that miRNAs mainly exert their role in cisplatin response through regulation of apoptosis, signaling pathways, and transcription factors in OC cells. This review highlighted the miRNAs as important regulators of cisplatin response in ovarian tumor cells. Moreover, present review paves the way of suggesting a non-invasive panel of prediction markers for cisplatin response among OC patients.

Inhibition of Long Noncoding RNA SNHG20 Improves Angiotensin II-Induced Cardiac Fibrosis and Hypertrophy by Regulating the MicroRNA 335/Galectin-3 Axis

Cardiac fibrosis is a hallmark of various heart diseases and ultimately leads to heart failure. Although long noncoding RNA (lncRNA) SNHG20 has been reported to play important roles in various cancers, its function in cardiac fibrosis remains unclear. The expression of SNHG20 and microRNA 335 (miR-335) in heart tissues of angiotensin II-induced mice and angiotensin II-stimulated mouse cardiomyocyte cell line HL-1 were detected by quantitative real-time PCR (qRT-PCR). Cell viability was evaluated by cell counting kit-8 assay. The expression of galectin-3, fibrosis-related proteins (fibronectin, collagen IaI, and α-SMA), and apoptosis-related proteins [cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase (PARP)] was detected by Western blotting. Bioinformatics prediction, luciferase reporter assay, and RNA pulldown assay were performed to determine the relationship between SNHG20 and miR-335 as well as miR-335 and Galectin-3. Gain- and loss-function assays were performed to determine the role of SNHG20/miR-335/Galectin-3 in cardiac fibrosis. SNHG20 was significantly upregulated and miR-335 was downregulated in heart tissues of angiotensin II-treated mice and angiotensin II-stimulated HL-1 cells. Downregulation of SNHG20 effectively enhanced cell viability and decreased cell size of HL-1 cells and the expression levels of fibrosis-related proteins (fibronectin, collagen IaI, and α-SMA) and apoptosis-related proteins (cleaved caspase-3 and cleaved PARP), which were induced by angiotensin II treatment. Furthermore, SNHG20 elevated the expression levels of Galectin-3 by directly regulating miR-335. Our study revealed that downregulation of SNHG20 improved angiotensin II-induced cardiac fibrosis by targeting the miR-335/Galectin-3 axis, suggesting that SNHG20 is a therapeutic target for cardiac fibrosis and hypertrophy.

MiR-3666 serves as a tumor suppressor in ovarian carcinoma by down-regulating AK4 via targeting STAT3

As a result of metastasis and high recurrence, ovarian carcinoma (OC) is one of the most frequent gynecological carcinomas affecting women up to now. In spite of advances in OC treatments, the molecular mechanisms underlying OC progression are still needed to be deeply understood. MicroRNAs (miRNAs) with aberrant expressions are widely known to regulate target genes so as to mediate diverse biological activities of tumor cells. In the present study, we inspected the expression profile and latent mechanism of miR-3666 in OC. First of all, our research revealed the down-regulated miR-3666 in OC cells. Furthermore, miR-3666 up-regulation could repress cell proliferation and migration as well as induce cell apoptosis in OC. In addition, we unmasked that miR-3666 targeted STAT3 (signal transducer and activator of transcription 3) and further down-regulated STAT3 expression. Moreover, adenylate kinase 4 (AK4) was transcriptionally enhanced by STAT3, and then miR-3666 restrained AK4 expression by mediating STAT3. In the end, rescue experiments depicted that miR-3666 suppressed the development of OC via STAT3-mediated AK4. We uncovered that miR-3666 inhibited the tumorigenesis and even development of OC via suppressing STAT3/AK4 axis, offering a novel biomarker and therapeutic target for OC.

Circular RNA CircCOL5A1 Sponges the MiR-7-5p/Epac1 Axis to Promote the Progression of Keloids Through Regulating PI3K/Akt Signaling Pathway

Keloids, as a result of abnormal wound healing in susceptible individuals, are characterized by the hyper-proliferation of fibroblasts and exaggerated deposition of extracellular matrix. Current surgical and therapeutic modalities provide limited satisfactory results. Growing evidence has highlighted the roles of circRNAs in acting as miRNA sponges. However, up to date, the regulatory mechanism of circRNAs in the pathological process of keloids has rarely been reported. In this study, cell proliferation, cell migration, flow cytometry, western blotting, fluorescence in situ hybridization, dual-luciferase activity, and immunohistochemistry assays were applied to explore the roles and mechanisms of the circCOL5A1/miR-7-5p/Epac1 axis in the keloid. The therapeutic potential of circCOL5A1 was investigated by establishing keloid implantation models. The RT-qPCR result revealed that circCOL5A1 expression was obviously higher in keloid tissues and keloid fibroblasts. Subsequent cellular experiments demonstrated that circCOL5A1 knockdown repressed the proliferation, migration, extracellular matrix (ECM) deposition, whereas promoted cell apoptosis, through the PI3K/Akt signaling pathway. Furthermore, RNA-fluorescence in situ hybridization (RNA-FISH) illustrated that both circCOL5A1 and miR-7-5p were located in the cytoplasm. The luciferase reporter gene assay confirmed that exact binding sites were present between circCOL5A1 and miR-7-5p, as well as between miR-7-5p and Epac1. Collectively, the present study revealed that circCOL5A1 functioned as competing endogenous RNA (ceRNA) by adsorbing miR-7-5p to release Epac1, which contributed to pathological hyperplasia of keloids through activating the PI3K/Akt signaling pathway. Our data indicated that circCOL5A1 might serve as a novel promising therapeutic target and represent a new avenue to understand underlying pathogenesis for keloids.

miR-424: A novel potential therapeutic target and prognostic factor in malignancies

microRNAs are endogenous, noncoding RNAs. Showing both tumor-suppressive and oncogenic characteristics, miRNAs can regulate important processes in malignancies. This review aimed at highlighting the recent studies on the contribution of miR-424 to the modulation of carcinogenesis and exploring its probable clinical effectiveness in the diagnosis and therapy of malignancies. The data were extracted from all papers published from 2013 until 2020. Mature miR-424 leads to the degradation of its target transcripts or the suppression of translation via binding to the molecular targets. miR-424 is involved in modulating p53, PI3K/Akt, Wnt, and other molecular pathways, thereby regulating cellular growth, apoptosis, differentiation, chemoresistance, and cancer immunity. miR-424 was introduced as a tumor-suppressive miR in numerous types of cancers while as an oncogene in several cancers. Regarding the cancer dependent role of miR-424, it may be a prognostic and diagnostic biomarker and a potential candidate for the treatment of cancers.

Identifying miRNA modules associated with progression of keloids through weighted gene co-expression network analysis and experimental validation in vitro

Keloid is a type of skin fibroproliferative disease, characterized by excessive deposition of collagen in the extracellular matrix, myofibroblast activation and invasive growth to the surrounding normal skin tissue. However, the specific pathogenesis of keloids is not yet fully understood and existing treatment strategies are unsatisfied. It is therefore urgent to explore new biomarkers associated with its progression for keloids. In this study, the microarray dataset GSE113620 was downloaded from the Gene Expression Omnibus (GEO) database to screen out the differential expression of miRNAs (DEMs). The DEMs with large variance were applied to construct a weighted gene co-expression network to identify miRNA modules that are closely relevant to keloid progression. It is worth noting that miR-424-3p in the blue module (r = 0.98, p = 1e-18) is considered to be the ultimate target most relevant to keloid progression through co-expressed network analysis. Subsequently, the results of molecular biology experiments determine that miR-424-3p targeting Smad7 significantly enhanced the ability of cell proliferation, migration and collagen secretion after transfection with miR-424-3p mimic, while the apoptosis rate was significantly reduced. On the contrary, the miR-424-3p inhibitor performs the exact opposite function.

The microRNA-424/503 cluster: A master regulator of tumorigenesis and tumor progression with paradoxical roles in cancer

MicroRNAs (miRNAs) are a group of non-coding RNAs that play a crucial role in post-transcriptional gene regulation and act as indispensable mediators in several critical biological processes, including tumorigenesis, tissue homeostasis, and regeneration. MiR-424 and miR-503 are intragenic miRNAs that are clustered on human chromosome Xq26.3. Previous studies have reported that both miRNAs are dysregulated and play crucial but paradoxical roles in tumor initiation and progression, involving different target genes and molecular pathways. Moreover, these two miRNAs are concomitantly expressed in several cancer cells, indicating a coordinating function as a cluster. In this review, the roles and regulatory mechanisms of miR-424, miR-503, and miR-424/503 cluster are summarized in different types of cancers.

miR-424-3p Contributes to the Malignant Progression and Chemoresistance of Gastric Cancer

BACKGROUND

Gastric cancer (GC) is one of the most common and lethal malignancies worldwide. Therefore, a better understanding of the mechanism of its malignant progression and chemoresistance will be helpful for the treatment of patients with GC.

METHODS

The gene expression profiles downloaded from GEO database and the TargetScan Human were used to identify the key regulation model based on miRNA by bioinformatics analyses. The regulation of miRNA to target was clarified by luciferase assay, qPCR, and Western blotting. Then, the in vitro and in vivo experiments were further conducted by overexpression or knockdown of miRNA and/or target to examine the regulation effects and clarify the mechanism.

RESULTS

In the present study, miR-424-3p was identified to be differentially expressed among normal gastric, GC, and chemoresistant GC tissues. Target analysis results indicated that ABCC2, a chemoresistance-related gene, was a regulated target of miR-424-3p. The in vitro and in vivo experiment results further demonstrated that miR-424-3p relied on ABCC2-induced chemoresistance to promote GC proliferation and metastasis.

CONCLUSION

Overall, this study revealed that miR-424-3p contributed to the malignant progression and chemoresistance of GC. Thus, miR-424-3p could be a potential target for the treatment of GC.

Paclitaxel exposure downregulates miR-522 expression and its downregulation induces paclitaxel resistance in ovarian cancer cells

Paclitaxel resistance is a critical challenge in ovarian cancer treatment. This study aimed to identify microRNAs (miRNAs) that modulate paclitaxel resistance for use as potential therapeutic targets in such settings. Paclitaxel-resistant cell lines were established using two ovarian cancer cell lines: SKOV3ip1 and HeyA8. The evaluation of miRNA polymerase chain reaction (PCR) arrays indicated that the expression of miR-522-3p was downregulated in paclitaxel-resistant cells. The restoration of miR-522-3p sensitized the resistant cells to paclitaxel, and its downregulation desensitized the parental cells. Using PCR arrays, we focused on E2F2, with the luciferase reporter assay revealing that it was a direct target for miR-522-3p. The paclitaxel-resistant cells showed stronger E2F2 expression than the parental cells, while E2F2 inhibition sensitized the resistant cells to paclitaxel. Forced E2F2 expression in the parental cells led to the acquisition of paclitaxel resistance, while miR-522-3p inhibited E2F2 expression and was associated with retinoblastoma protein phosphorylation attenuation, which resulted in G0/G1 arrest. The effects of miR-522-3p and E2F2 in ovarian cancer were examined using public databases, revealing that low miR-522-3p expression and high E2F2 expression were associated with significantly poorer overall survival. In conclusion, miR-522-3p attenuated the degree of paclitaxel resistance in vitro through the downregulation of E2F2; miR-522-3p supplementation may be a therapeutic target for paclitaxel-resistant ovarian cancer.

Role of miRNA-424 in Cancers

microRNA (miRNA) is an important part of non-coding RNA that regulates gene expression at a posttranscriptional level. miRNA has gained increasing interest in recent years, both in research and clinical fields. miRNAs have been found to play an important role in various diseases, particularly cancer. Aberrant miR-424 expression is found in several tumors where they can function as either oncogenes or tumor-suppressor genes. Meanwhile, miR-424 is also affected by the reorganization of many other non-coding RNAs such as lncRNA and cirRNA. Several studies have found that miR-424 participates in proliferation, differentiation, apoptosis, invasion, angiogenesis, and drug resistance, and plays an important role in the tumorigenesis and progression of tumors. This review will focus on the recent progress of research on miR-424 in tumors.

The apoptotic effect of resveratrol in ovarian cancer cells is associated with downregulation of galectin-3 and stimulating miR-424-3p transcription

This study investigated if the well-reported anti-tumor effects of resveratrol (RES) is mediated by modulation levels of galectin-3 (GAL-3), an anti-apoptotic lectin that is highly overexpressed in ovarian cancer cells. SKOV3 and OVCAR-3 OC cells were untreated or incubated with DMOS or increasing concentrations of RES (25, 50, 100 μM) for 72 hr. RES, in a dose-dependent manner and in both cell lines, induced cell death and inhibited cell migration and invasion It also downregulated Bcl-2 levels, increased cleaved caspase-3, and GAL-3 protein (but not mRNA) levels, suggesting increased breakdown. These effects were associated with reduced levels of p-NF-κB P65, p-IKKα/β, and p-Akt, major targets of Gal-3. Further investigation showed that RES enhanced levels of miR-424-3p which is able to degrade GAL-3. Conclusion: Findings of this study suggest that RES induced apoptosis in cancerous cells is associated with increased levels of miR-424-3p and reduced levels of GAL-3. PRACTICAL APPLICATIONS: This study highlights a possible mechanism by which RES could enhance cell death in OC cells and enhances their sensitivity to cisplatin. RES apoptotic effect and enhancement of OC cells to chemotherapy were associated with decreased abundance of GAL-3, a common cell survival molecule that promotes tumorigenesis and increased transcription of miR-424-3p that has the ability to degrade cellular GAL-3. These findings add a possible new mechanism by which RES acts and opens a window for further research to understand its mechanism of action.

MicroRNA-424 regulates cisplatin resistance of gastric cancer by targeting SMURF1 based on GEO database and primary validation in human gastric cancer tissues

PURPOSE

Cisplatin (DDP) based chemotherapy regimens are widely used in advanced gastric cancer (GC). Drug resistance often limited the clinical benefits of cisplatin regimen. The mechanisms of cisplatin resistance have not been fully revealed. Therefore, further exploration of the relevant molecular mechanisms is urgently needed.

PATIENTS AND METHODS

DDP resistance associated miRNA of GC microarray dataset GSE86195 was obtained from the National Center for Biotechnology Information (NCBI) GEO database, GEO2R was applied to compare the samples in two different groups under the same experimental conditions. |log2(Fold Change) | (log2(FC)) was selected as the criteria to screen the statistically significant DE-miRNAs. StarBaseV3.0 was used to predict the target genes of the DE-miRNAs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses of target genes of DE-miRNAs were carried out using DAVID. The STRING database was applied to estimate the correlations between target genes. Analysis of hubgenes by coremine and The Human Protein Atlas (THPA). Initial expression validations of miR-424 and miR-491-5p, SMURF1 and BCL2L1 were carried out using clinical pathological specimens by RT-PCR.

RESULTS

A total of 13 Differential expression-miRNAs (DE-miRNAs) were identified in DDP chemoresistant cells, including 9 upregulated miRNAs and 4 downregulated miRNAs. SMURF1 and BCL2L1 were screened as the critical genes in DDP-resistant GC, which were regulated by miR-424 and miR-491-5p respectively. The results of validation of hub genes expression in GC tissues indicated that in DFS<1-year group, the expression of miR-424 decreased significantly, notably upregulated expression of SMURF1 was also detected.

CONCLUSION

Our results implied that miR-424, as a tumor suppressor, could deregulate SMURF1 in DDP-resistant GC cells.

NFKB1-miR-612-FAIM2 pathway regulates tumorigenesis in neurofibromatosis type 1

Neurofibromatosis type I (NF1) is a carcinoma mainly featured by malignant peripheral nerve sheath tumor (MPNST). Dysregulated microRNAs (miRNAs) play decisive roles in tumor initiation and development. Our study sought for the possible roles of miR-612 in NF1. RT-qPCR estimated the expression of nuclear factor kappa B subunit 1 (NFKB1), miR-612, and Fas apoptotic inhibitory molecule 2 (FAIM2) in NF1, separately. Cell proliferation and migration were detected by CCK-8 and transwell experiments. Cell apoptosis was measured via flow cytometry and detection of the expression and activity of caspase 3/8/9. Luciferase reporter, ChIP, and RIP assays testified the interplay between studied genes. Rescue and in vivo assays affirmed the whole mechanism of miR-612 in NF1. We indicated that miR-612 was significantly low in tumor tissues and cells. Mechanism experiments confirmed that miR-612 promotion repressed cell proliferation and migration, and induced cell apoptosis. Besides, NFKB1-regulated miR-612 targeted FAIM2. Spearman's correlation analysis validated the correlation between each two genes. Finally, rescue and in vivo assays affirmed that miR-612 targeted FAIM2 to regulate cellular activities of NF1. The current investigation uncovered the molecular mechanism underlying miR-612 in NF1, establishing miR-612 as a novel therapeutic target for the treatment of NF1 patients.