Silibinin-Induced Apoptosis and Downregulation of MicroRNA-21 and MicroRNA-155 in MCF-7 Human Breast Cancer Cells

Silibinin-Loaded Nanoparticles for Drug Delivery in Gastric Cancer: In Vitro Modulating miR-181a and miR-34a to Inhibit Cancer Cell Growth and Migration

Silibinin (C25H22O10), a notable bioactive flavonolignans, is recognized for its anticancer properties. However, due to its poor water solubility, the objective of this study was to design and synthesize nanocarriers to enhance the solubility of silibinin for effective delivery to AGS gastric cancer cells. This study details the synthesis of PEG400-OA nanoparticles for silibinin delivery to AGS cells. Various physicochemical techniques, including FT-IR, TGA, EDX, FE-SEM, and TEM, were employed to characterize the silibinin-loaded nanoparticles (SLNs), confirming particle size, elemental composition, thermal stability, and paramagnetic properties. The anticancer effects of the SLNs were assessed using MTT assay, scratch test, and Q-RT-PCR. The SLNs exhibited particle sizes ranging from 45 to 60 nm, with thermal stability below 110°C. TEM images suggested a micelles/liposomes structure due to the low polydispersity and spherical shape of the particles. EDX analysis revealed the presence of C, O, N, and P, confirming the incorporation of phospholipids (micelle/liposome) within the SLNs. The IC50 of SLNs in AGS cells was determined to be 28.21 μg/mL. Antimigration effects of SLNs's were demonstrated through the downregulation of miR-181a and upregulation of its potential targets (TGFB, SMAD3, and β-catenin genes), as well as the upregulation of miR-34a and downregulation of its potential target (E-Cadherin antimigration gene). The findings suggest that nanoparticles serve as effective nanocarriers for the targeted delivery of silibinin to cancer cells. Silibinin-loaded micelles/liposomes nanoparticles (SLNs) appear to inhibit cancer cell proliferation and migration by modulating the expressionof miRNAs and their target mRNAs.

The protection of bisphenol A-modulated miRNAs and targets by natural products

Bisphenol A (BPA) is a ubiquitous environmental pollutant with endocrine-disrupting functions. Identifying protective drugs and exploring the mechanisms against BPA are crucial in healthcare. Natural products exhibiting antioxidant properties are considered to be able to protect against BPA toxicity. Although BPA-modulated targets and miRNAs have been individually reported, their connections to natural products were rarely organized. With the help of a protein-protein interaction database (STRING), the relationship between individual BPA-modulated targets was interconnected to provide a systemic view. In this review, BPA-downregulated and -upregulated targets are classified, and their interactive network was innovatively analyzed using the bioinformatic database (STRING). BPA-modulated miRNAs were also retrieved and ingeniously connected to BPA-modulated targets. Moreover, a novel connection between BPA-countering natural products was integrated into BPA-modulated miRNAs and targets. All these targets-associated natural products and/or miRNAs were incorporated into the STRING network, providing systemic relationships. Overall, the BPA-modulated target-miRNA-protecting natural product axis was innovatively constructed, providing a straightforward direction for exploring the integrated BPA-countering effects and mechanisms of natural products.

MicroRNA-21 (miR-21) in breast cancer: From apoptosis dysregulation to therapeutic opportunities

Breast cancer, a pervasive and complex disease, continues to pose significant challenges in the field of oncology. Its heterogeneous nature and diverse molecular profiles necessitate a nuanced understanding of the underlying mechanisms driving tumorigenesis and progression. MicroRNA-21 (miR-21) has emerged as a crucial player in breast cancer development and progression by modulating apoptosis, a programmed cell death mechanism that eliminates aberrant cells. MiR-21 overexpression is a hallmark of breast cancer, and it is associated with poor prognosis and resistance to conventional therapies. This miRNA exerts its oncogenic effects by targeting various pro-apoptotic genes, including Fas ligand (FasL), programmed cell death protein 4 (PDCD4), and phosphatase and tensin homolog (PTEN). By suppressing these genes, miR-21 promotes breast cancer cell survival, proliferation, invasion, and metastasis. The identification of miR-21 as a critical regulator of apoptosis in breast cancer has opened new avenues for therapeutic intervention. This review investigates the intricate mechanisms through which miR-21 influences apoptosis, offering insights into the molecular pathways and signaling cascades involved. The dysregulation of apoptosis is a hallmark of cancer, and understanding the role of miR-21 in this context holds immense therapeutic potential. Additionally, the review highlights the clinical significance of miR-21 as a diagnostic and prognostic biomarker in breast cancer, underscoring its potential as a therapeutic target.

A comprehensive evaluation of the therapeutic potential of silibinin: a ray of hope in cancer treatment

Natural compounds hold promise in the search for cancer therapies due to their unique chemical structures and combinations that may effectively combat cancer while minimizing toxicity and side effects compared to conventional treatments. Silibinin, a natural lignan, has been found to possess strong anti-cancer activity against several types of human cancers based on emerging research. This study aims to provide an overview of the therapeutic potential of silibinin in the treatment and prevention of cancers. A comprehensive search was conducted using various internet databases such as PubMed, Google Scholar, and ScienceDirect to identify relevant research papers. Silibinin has been shown to exhibit anticancer activity against several types of cancers, including liver, lungs, breast, prostate, colorectal, skin, and bladder cancers. Its multifaceted mechanisms of action contribute to its therapeutic effects. Silibinin exerts antioxidant, anti-inflammatory, anti-proliferative, pro-apoptotic, anti-metastatic, and anti-angiogenic activities, making it a promising candidate for cancer therapy. One of the key mechanisms underlying the anticancer effects of silibinin is its ability to modulate multiple signaling pathways involved in cancer development and progression. It can inhibit the activation of various oncogenic pathways, including PI3K/Akt, NF-κB, Wnt/β-catenin, and MAPK pathways, thereby suppressing cancer cell proliferation, inducing cell cycle arrest, and promoting apoptosis. Silibinin possesses great potential as an effective treatment agent for cancer. The multifaceted mechanisms of action, favorable safety profile, and potential synergistic effects of silibinin with conventional therapies make it an attractive candidate for further investigation and development as a cancer treatment. However, more extensive clinical studies are necessary to fully establish the efficacy, optimal dosage, and long-term effects of silibinin in cancer treatment.

Co-treatment of silymarin and cisplatin inhibited cell proliferation, induced apoptosis in ovarian cancer

BACKGROUND

Ovarian cancer is one of the most lethal gynecological cancers among women worldwide. Cisplatin (Cis) is an effective chemotherapeutic agent used to treat several types of cancer. Silymarin (SLM) is an extract of medicinal plant Silybum marianum (milk thistle) with anti-inflammatory, anti-angiogenesis, antioxidant, and anticancer properties used alone or in combination with other drugs.

OBJECTIVE

This study aimed to explore the effects of co-treatment with SLM and Cis on A2780 human ovarian cancer cell lines.

METHODS

In this study, A2780 cells were treated with various concentrations of SLM and Cis, separately and in combination. Cell cytotoxicity, scratch, clonogenic, and flow-cytometry assays were accomplished to estimate cell viability, migration, colony formation, and apoptosis, respectively. Real-time PCR was utilized to determine the expression levels of miR-155 and miR-27a.

RESULTS

SLM significantly reduced the proliferation of A2780 cells in a concentration- and time-dependent manner. Combination treatment with SLM and Cis was more potent than either single treatment in reducing viability, suppressing migration, inhibiting colony formation, and promoting the induction of apoptosis. Additionally, gene expression analysis revealed a significant decline in the expression levels of miR-155 and miR-27a in response to all separate and combined treatments, and co-treatment was more effective than individual treatments in altering miRNAs expression.

CONCLUSION

Based on our findings, SLM boosts the anticancer activity of Cis and mitigates its side effects. Thus, the co-treatment of SLM and Cis can be proposed as a promising therapeutic strategy for further investigation.

The role of miR-133a in silibinin-mediated inhibition of the PI3K/AKT/mTOR pathway in MCF-7 breast carcinoma cells

Breast cancer is particularly severe in women. Research highlights the crucial role of miRNAs in key cellular processes, showcasing their intricate interactions with the oncogenic PI3K/AKT/mTOR (PAM) signaling pathway and underscoring their significant role as tumor suppressors. The effect of silibinin on cell growth and survival was evaluated using an MTT assay. Bioinformatics analysis identified putative miR-133a targets inside the PAM pathway. After incubating MCF-7 cells with silibinin, we measured miR-133a, EGFR, PI3K, AKT, PTEN, and mTOR expression levels using qRT-PCR. Furthermore, protein expression levels of mTOR were assessed using Western blotting. The MTT experiment displayed that silibinin effectively inhibits MCF-7 cell proliferation in a time- and dose-dependent manner. Silibinin's IC50 value, determined at 370 μM after 48 hours, was established. qRT-PCR analysis at this IC50 concentration highlighted reduced expression of EGFR, PI3K, AKT, PTEN, and mTOR mRNAs, alongside increased miR-133a expression. Notably, miR-133a exhibited a negative correlation with both EGFR and PIK3C2A expression. Furthermore, western blotting confirmed silibinin's capacity to diminish p-mTOR protein levels, the ultimate element of the PAM signaling pathway. The findings enhance comprehension of silibinin's impact on PAM signaling and miR-133a expression, offering promise for targeted therapies in disrupting oncogenic pathways in MCF-7 breast cancer cells. This insight could advance breast cancer treatment strategies.

A highly sensitive colorimetric DNA sensor for MicroRNA-155 detection: leveraging the peroxidase-like activity of copper nanoparticles in a double amplification strategy

A novel and highly sensitive colorimetric DNA sensor for determination of miRNA-155 at attomolar levelsis presented that combines the peroxidase-like activity of copper nanoparticles (CuNPs) with the hybridization chain reaction (HCR) . The utilization of CuNPs offers advantages such as strong interaction with double-stranded DNA, excellent molecular recognition, and mimic catalytic activity. Herein, a capture probe DNA (P1) was immobilized on carboxylated magnetic beads (MBs), allowing for amplified immobilization due to the 3D surface. Subsequently, the presence of the target microRNA-155 led to the formation of a sandwich structure (P2/microRNA-155/P1/MBs) when P2 was introduced to the modified P1/MBs. The HCR reaction was then triggered by adding H1 and H2 to create a super sandwich (H1/H2)n. Following this, Cu2+ ions were attracted to the negatively charged phosphate groups of the (H1/H2)n and reduced by ascorbic acid, resulting in the formation of CuNPs, which were embedded into the grooves of the (H1/H2)n. The peroxidase-like activity of CuNPs catalyzed the oxidation reaction of 3,3',5,5'-Tetramethylbenzidine (TMB), resulting in a distinct blue color measured at 630 nm. Under optimal conditions, the colorimetric biosensor exhibited a linear response to microRNA-155 concentrations ranging from 80 to 500 aM, with a detection limit of 22 aM, and discriminate against other microRNAs. It was also successfully applied to the determination of microRNA-155 levels in spiked human serum.

Effect of Silibinin on the Expression of Mir-20b, Bcl2L11, and Erbb2 in Breast Cancer Cell Lines

This study aimed to evaluate the comparative effect of silibinin (SB) on the expression of MiR‑20b and BCL2L11 in T47D and MCF-7 cell lines. Molecular simulation studies were carried out to analyze Erbb2, as a potential target of SB, to direct the breast cancer cells toward apoptosis. At first, cell viability, apoptosis, and cell cycle arrest-inducing capacity of SB were examined using MTT and flow cytometry analysis, respectively. Real-time PCR (RT-PCR) was employed to assess the effect of SB on BCL2L11, Phosphatase and tensin homolog (PTEN), and Caspase 9 mRNarrest-indu. Moreover, alterations in Caspase 9 protein expression were determined using Western blot analysis. Finally, AutoDockVina software was used to dock the SB/ MiR‑20b and SB/ erb-b2 receptor tyrosine kinase 2 (Erbb2) interaction. The obtained data revealed the potent cytotoxicity of SB in both T47D and MCF-7 cells through apoptosis induction and cell cycle arrest. SB-treated cells also showed downregulation of MiR‑20b and high expression of BCL2L11, PTEN, and Caspase 9 mRNA compared to non-treated cancer cells. Computational docking showed a strong interaction between SB/ MiR‑20b and SB/Erbb2. It can be concluded that SB had a strong anti-tumorigenic activity through BCL2L11upregulation and MiR‑20b down expression, maybe through targeting the PTEN and interacting with Erbb2, which resulted in apoptotic induction and cell cycle arrest.

Plant-Derived Epi-Nutraceuticals as Potential Broad-Spectrum Anti-Viral Agents

Although the COVID-19 pandemic appears to be diminishing, the emergence of SARS-CoV-2 variants represents a threat to humans due to their inherent transmissibility, immunological evasion, virulence, and invulnerability to existing therapies. The COVID-19 pandemic affected more than 500 million people and caused over 6 million deaths. Vaccines are essential, but in circumstances in which vaccination is not accessible or in individuals with compromised immune systems, drugs can provide additional protection. Targeting host signaling pathways is recommended due to their genomic stability and resistance barriers. Moreover, targeting host factors allows us to develop compounds that are effective against different viral variants as well as against newly emerging virus strains. In recent years, the globe has experienced climate change, which may contribute to the emergence and spread of infectious diseases through a variety of factors. Warmer temperatures and changing precipitation patterns can increase the geographic range of disease-carrying vectors, increasing the risk of diseases spreading to new areas. Climate change may also affect vector behavior, leading to a longer breeding season and more breeding sites for disease vectors. Climate change may also disrupt ecosystems, bringing humans closer to wildlife that transmits zoonotic diseases. All the above factors may accelerate the emergence of new viral epidemics. Plant-derived products, which have been used in traditional medicine for treating pathological conditions, offer structurally novel therapeutic compounds, including those with anti-viral activity. In addition, plant-derived bioactive substances might serve as the ideal basis for developing sustainable/efficient/cost-effective anti-viral alternatives. Interest in herbal antiviral products has increased. More than 50% of approved drugs originate from herbal sources. Plant-derived compounds offer diverse structures and bioactive molecules that are candidates for new drug development. Combining these therapies with conventional drugs could improve patient outcomes. Epigenetics modifications in the genome can affect gene expression without altering DNA sequences. Host cells can use epigenetic gene regulation as a mechanism to silence incoming viral DNA molecules, while viruses recruit cellular epitranscriptomic (covalent modifications of RNAs) modifiers to increase the translational efficiency and transcript stability of viral transcripts to enhance viral gene expression and replication. Moreover, viruses manipulate host cells' epigenetic machinery to ensure productive viral infections. Environmental factors, such as natural products, may influence epigenetic modifications. In this review, we explore the potential of plant-derived substances as epigenetic modifiers for broad-spectrum anti-viral activity, reviewing their modulation processes and anti-viral effects on DNA and RNA viruses, as well as addressing future research objectives in this rapidly emerging field.

Milk thistle nano-micelle formulation promotes cell cycle arrest and apoptosis in hepatocellular carcinoma cells through modulating miR-155-3p /SOCS2 /PHLDA1 signaling axis

BACKGROUND

Hepatocellular Carcinoma (HCC) is a prevalent form of liver cancer that causes significant mortality in numerous individuals worldwide. This study compared the effects of milk thistle (MT) and nano-milk thistle (N-MT) on the expression of the genes that participate in apoptosis and cell cycle pathways in Huh-7 and HepG2 cells.

METHODS

IC50 values of MT and N-MT were determined using the MTT assay. Huh-7 and HepG2 cell lines (containing mutant and wild-type TP53 gene, respectively) were incubated with MT and N-MT for 24h and 48h and the impact of MT and N-MT on the proliferation of these cell lines was evaluated through a comparative analysis. Cell cycle and apoptosis were assessed by flow cytometry after 24h and 48h treatment in the cell lines mentioned. Real-time PCR was used to analyze miR-155-3p, PHLDA1, SOCS2, TP53, P21, BAX, and BCL-2 expression in the cell lines that were being treated.

RESULTS

N-MT reduces cancer cell growth in a time and concentration-dependent manner, which is more toxic compared to MT. Huh-7 was observed to have IC50 values of 2.35 and 1.7 μg/ml at 24h and 48h, and HepG2 was observed to have IC50 values of 3.4 and 2.6 μg/ml at 24 and 48h, respectively. N-MT arrested Huh-7 and HepG2 cells in the Sub-G1 phase and induced apoptosis. N-MT led to a marked reduction in the expression of miR-155-3p and BCL-2 after 24h and 48h treatments. Conversely, PHLDA1, SOCS2, BAX, and P21 were upregulated in the treated cells compared to untreated cells, which suggests that milk thistle has the potential to regulate these genes. N-MT reduced the expression of TP53 in Huh-7 cells after mentioned time points, while there was a significant increase in the expression of the TP53 gene in HepG2 cells. No gene expression changes were observed in MT-treated cells after 24h and 48h.

CONCLUSION

N-MT can regulate cancer cell death by arresting cell cycle and inducing apoptosis. This occurs through the alteration of apoptotic genes expression. A reduction in the expression of miR-155-3p and increase in the expression of SOCS2 and PHLDA1 after N-MT treatment showed the correlation between miR-155-3p and PHLDA1/SOCS2 found in bioinformatics analysis. While N-MT increased TP53 expression in HepG2, reduced it in Huh-7. The findings indicate that N-MT can function intelligently in cancer cells and can be a helpful complement to cancer treatment.

Therapeutic advancements in targeting BCL-2 family proteins by epigenetic regulators, natural, and synthetic agents in cancer

Cancer is amongst the deadliest and most disruptive disorders, having a much higher death rate than other diseases worldwide. Human cancer rates continue to rise, thereby posing the most significant concerns for medical health professionals. In the last two decades, researchers have gone past several milestones in tackling cancer while gaining insight into the role of apoptosis in cancer or targeting various biomarker tools for prognosis and diagnosis. Apoptosis which is still a topic full of complexities, can be controlled considerably by B-cell lymphoma 2 (BCL-2) and its family members. Therefore, targeting proteins of this family to prevent tumorigenesis, is essential to focus on the pharmacological features of the anti-apoptotic and pro-apoptotic members, which will help to develop and manage this disorder. This review deals with the advancements of various epigenetic regulators to target BCL-2 family proteins, including the mechanism of several microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). Similarly, a rise in natural and synthetic molecules' research over the last two decades has allowed us to acquire insights into understanding and managing the transcriptional alterations that have led to apoptosis and treating various neoplastic diseases. Furthermore, several inhibitors targeting anti-apoptotic proteins and inducers or activators targeting pro-apoptotic proteins in preclinical and clinical stages have been summarized. Overall, agonistic and antagonistic mechanisms of BCL-2 family proteins conciliated by epigenetic regulators, natural and synthetic agents have proven to be an excellent choice in developing cancer therapeutics.

The Role of Natural Products as Inhibitors of JAK/STAT Signaling Pathways in Glioblastoma Treatment

The permeability of glioblastoma, as well as its escaping the immune system, makes them one of the most deadly human malignancies. By avoiding programmed cell death (apoptosis), unlimited cell growth and metastatic ability could dramatically affect the immune system. Genetic mutations, epigenetic changes, and overexpression of oncogenes can cause this process. On the other hand, the blood-brain barrier (BBB) and intratumor heterogeneity are important factors causing resistance to therapy. Several signaling pathways have been identified in this field, including the Janus tyrosine kinase (JAK) converter and signal transducer and activator of transcription (STAT) activator pathways, which are closely related. In addition, the JAK/STAT signaling pathway contributes to a wide array of tumorigenesis functions, including replication, anti-apoptosis, angiogenesis, and immune suppression. Introducing this pathway as the main tumorigenesis and treatment resistance center can give a better understanding of how it operates. In light of this, it is an important goal in treating many disorders, particularly cancer. The inhibition of this signaling pathway is being considered an approach to the treatment of glioblastoma. The use of natural products alternatively to conventional therapies is another area of research interest among researchers. Some natural products that originate from plants or natural sources can interfere with JAK/STAT signaling in human malignant cells, also by stopping the progression and phosphorylation of JAK/STAT, inducing apoptosis, and stopping the cell cycle. Natural products are a viable alternative to conventional chemotherapy because of their cost-effectiveness, wide availability, and almost no side effects.

Phytochemicals mediated modulation of microRNAs and long non-coding RNAs in cancer prevention and therapy

MicroRNAs (miRNAs) and long noncoding RNAs (lncRNAs) are two main categories of noncoding RNAs (ncRNAs) that can influence essential biological functions in various ways, as well as their expression and function are tightly regulated in physiological homeostasis. Additionally, the dysregulation of these ncRNAs seems to be crucial to the pathogenesis of human diseases. The latest findings indicate that ncRNAs execute vital roles in cancer initiation and progression, and the cancer phenotype can be reversed by modulating their expression. Available scientific discoveries suggest that phytochemicals such as polyphenols, alkaloids, terpenoids, and organosulfur compounds can significantly modulate multiple cancer-associated miRNAs and lncRNAs, thereby inhibiting cancer initiation and development. However, despite promising outcomes of experimental research, only a few clinical trials are currently being conducted to evaluate the therapeutic effectiveness of these compounds. Nevertheless, understanding phytochemical-mediated ncRNA regulation in cancer and the underlying molecular mechanisms on tumor pathophysiology can aid in the development of novel therapeutic strategies to combat this deadly disease.

Synergistic anti-cancer effects of silibinin-etoposide combination against human breast carcinoma MCF-7 and MDA-MB-231 cell lines

OBJECTIVES

Recently, there is a significant focus on combination chemotherapy for cancer using a cytotoxic drug and a phytochemical compound. We investigated the effect of silibinin on etoposide-induced apoptosis in MCF-7 and MDA-MB-231 breast carcinoma cell lines.

MATERIALS AND METHODS

The cytotoxic effects of silibinin and etoposide were determined using MTT assay after 24 and 48 hr incubation with these drugs individually and combined. The mRNA expression of Bax and Bcl2, and protein levels of P53, phosphorylated p53 (P-P53), and P21 were determined using real-time PCR and western blot analysis, respectively. The caspase 9 activity was measured using an ELISA kit.

RESULTS

Silibinin and etoposide alone and combined significantly inhibit cell growth in a dose and time-dependent manner in both cell lines. The strongest synergistic effects in terms of MCF-7 cell growth inhibition [combination index (CI) = 0.066] were evident. The silibinin-etoposide combinations cause a much powerful apoptotic death (47% and 40%) compared with each compound individually in MCF-7 and MDA-MB 231 cells, respectively. Additionally, the silibinin-etoposide combinations significantly increased the expression of P53, P-P53, and P21 in MCF-7 cells. Neither silibinin nor etoposide individually increased the level of P53 and P-P53 in MDA-MB-231 cells, but both of them individually and combined increased the level of P21.

CONCLUSION

Since the silibinin-etoposide combination induces apoptosis in both cell lines with and without expression of p53, thus, it is suggested that this combination may be a successful therapeutic strategy for breast cancer regardless of P53 status.

Role of Phytonutrients in Nutrigenetics and Nutrigenomics Perspective in Curing Breast Cancer

Breast cancer (BC) is one of the most common type of cancer and an important contributor to female mortality. Several genes and epigenetic modifications are involved in the development and progression of BC. Research in phytochemistry, nutrigenomics, and nutrigenetics has provided strong evidence that certain phytonutrients are able to modulate gene expression at transcriptional and post-transcriptional levels. Such phytonutrients may also be beneficial to prevent and treat BC. In this review, we will focus on the nutrigenomic effects of various phytochemicals including polyphenols, phytosterols, terpenoids, alkaloids, and other compounds from different sources. Overall, these phytonutrients are found to inhibit BC cell proliferation, differentiation, invasion, metastasis, angiogenesis, and induce apoptotic cell death by targeting various molecular pathways. They also alter epigenetic mechanisms and enhance the chemosensitivity and radiosensitivity of cancer cells. Such phytochemicals may be used for the effective management of BC patients in the clinical setting in the future. The present article aims to summarize the specific molecular pathways involved in the genetic effects of phytochemicals in BC.

Path of Silibinin from diet to medicine: A dietary polyphenolic flavonoid having potential anti-cancer therapeutic significance

In the last few decades, targeting cancer by the use of dietary phytochemicals has gained enormous attention. The plausible reason and believe or mind set behind this fact is attributed to either lesser or no side effects of natural compounds as compared to the modern chemotherapeutics, or due to their conventional use as dietary components by mankind for thousands of years. Silibinin is a naturally derived polyphenol (a flavonolignans), possess following biochemical features; molecular formula C25H22O10, Molar mass: 482.44 g/mol, Boiling point 793 °C, with strikingly high antioxidant and anti-tumorigenic properties. The anti-cancer properties of Silibinin are determined by a variety of cellular pathways which include induction of apoptosis, cell cycle arrest, inhibition of angiogenesis and metastasis. In addition, Silibinin controls modulation of the expression of aberrant miRNAs, inflammatory response, and synergism with existing anti-cancer drugs. Therefore, modulation of a vast array of cellular responses and homeostatic aspects makes Silibinin an attractive chemotherapeutic agent. However, like other polyphenols, the major hurdle to declare Silibinin a translational chemotherapeutic agent, is its lesser bioavailability. After summarizing the chemistry and metabolic aspects of Silibinin, this extensive review focuses on functional aspects governed by Silibinin in chemoprevention with an ultimate goal of summarizing the evidence supporting the chemopreventive potential of Silibinin and clinical trials that are currently ongoing, at a single platform.

Remodeling the Epigenetic Landscape of Cancer-Application Potential of Flavonoids in the Prevention and Treatment of Cancer

Epigenetics, including DNA methylation, histone modification, and noncoding RNA regulation, are physiological regulatory changes that affect gene expression without modifying the DNA sequence. Although epigenetic disorders are considered a sign of cell carcinogenesis and malignant events that affect tumor progression and drug resistance, in view of the reversible nature of epigenetic modifications, clinicians believe that associated mechanisms can be a key target for cancer prevention and treatment. In contrast, epidemiological and preclinical studies indicated that the epigenome is constantly reprogrammed by intake of natural organic compounds and the environment, suggesting the possibility of utilizing natural compounds to influence epigenetics in cancer therapy. Flavonoids, although not synthesized in the human body, can be consumed daily and are common in medicinal plants, vegetables, fruits, and tea. Recently, numerous reports provided evidence for the regulation of cancer epigenetics by flavonoids. Considering their origin in natural and food sources, few side effects, and remarkable biological activity, the epigenetic antitumor effects of flavonoids warrant further investigation. In this article, we summarized and analyzed the multi-dimensional epigenetic effects of all 6 subtypes of flavonoids (including flavonols, flavones, isoflavones, flavanones, flavanols, and anthocyanidin) in different cancer types. Additionally, our report also provides new insights and a promising direction for future research and development of flavonoids in tumor prevention and treatment via epigenetic modification, in order to realize their potential as cancer therapeutic agents.

Liposomal Form of L-Dopa and SH-Sy5y Cell-Derived Exosomes Modulate the Tyrosine Hydroxylase/Dopamine Receptor D2 Signaling Pathway in Parkinson's Rat Models

Parkinson's disease is a progressive neurodegenerative disorder in which dopaminergic neurons located in the substantia nigra are gradually lost. Currently, combined treatment strategies are receiving increasing attention as potential therapeutic approaches for Parkinson's disease. This study aimed to evaluate the potential effects of exosomes released from SH-Sy5y cells and the liposomal form of L-dopa on Parkinson's rat models. Twenty-five male Wistar albino rats, in five groups, were included in this study. Parkinson's disease was induced through microinjection of 6-OHDA (2.5 mg/mL) into the right substantia nigra. The exosomes released from the SH-Sy5y cell line were isolated and administered (0.2 µg/5 µL) alone or in combination with the liposomal form of L-Dopa (80 mg/kg) to the defined model groups. Behavioral tests and molecular assays were conducted to evaluate the expression levels of tyrosine hydroxylase (TH) and dopamine receptor D2 (DRD2). The rats in the groups receiving the combined liposomal form of L-Dopa and exosome treatment and the liposomal form of L-Dopa alone showed a significant improvement in their movement ability (p < 0.05). At molecular levels, these two groups also exhibited significant increases in Th (0.005 ± 0.001) and Drd2 (0.002 ± 0.0001) expression compared to controls (p < 0.05). The observed alterations of Th and Drd2 expression were not statistically significant in exosome- and L-Dopa-treated groups. The current study shows that exosome-derived neuronal cells and liposomal form of L-Dopa can protect different cells against pathological complications such as Parkinson's disease.

The Anticancer Properties of Silibinin: Its Molecular Mechanism and Therapeutic Effect in Breast Cancer

BACKGROUND

Silibinin (SB), the main component of Silymarin (SM), is a natural substance obtained from the seeds of the milk thistle. SM contains up to 70% of SB as two isoforms: A and B. It has an antioxidant and anti-inflammatory effect on hepatocytes and is known to inhibit cell proliferation, induce apoptosis, and curb angiogenesis. SB has demonstrated activity against many cancers, such as skin, liver, lung, bladder, and breast carcinomas.

METHODS

This review presents current knowledge of the use of SM in breast cancer, this being one of the most common types of cancer in women. It describes selected molecular mechanisms of the action of SM; for example, although SB influences both Estrogen Receptors (ER), α and β, it has opposite effects on the two. Its action on ERα influences the PI3K/AKT/mTOR and RAS/ERK signaling pathways, while by up-regulating ERβ, it increases the numbers of apoptotic cells. In addition, ERα is involved in SB-induced autophagy, while ERβ is not. Interestingly, SB also inhibits metastasis by suppressing TGF-β2 expression, thus suppressing Epithelial to Mesenchymal Transition (EMT). It also influences migration and invasive potential via the Jak2/STAT3 pathway.

RESULTS

SB may be a promising enhancement of BC treatment: when combined with chemotherapeutic drugs such as carboplatin, cisplatin, and doxorubicin, the combination exerts a synergistic effect against cancer cells. This may be of value when treating aggressive types of mammary carcinoma.

CONCLUSION

Summarizing, SB inhibits proliferation, induces apoptosis, and restrains metastasis via several mechanisms. It is possible to combine SB with different anticancer drugs, an approach that represents a promising therapeutic strategy for patients suffering from BC.

Role of exopolysaccharides (EPSs) as anti-Mir-155 in cancer cells

Micro-RNAs (MiRNAs) are a class of small non-coding RNAs that regulate cellular gene expression. MiR-155 overexpression has been implicated in many types of cancer. Besides, miR-155 appears to help tumor invasion and migration and works as a moderator of epithelial-to-mesenchymal transition (EMT). Exopolysaccharides (EPSs) are a large group of natural heterogeneous polymers of sugars with a biologically antitumor effect. Herein, we test a hypothesis that EPS might promote its anti-tumorigenic effect via regulating miR-155 expression and its target pathways. Expression of miR-155 and a panel of targeted genes were investigated by real-time PCR. In our study, we have succeeded in the extraction, purification of exopolysaccharide with great cytotoxicity to different cancer cell lines, HepG II, Caco-2, and MCF-7. We reported that EPSs have a suppression effect on the oncogenic miR-155. In conclusion, this work clarifies a new possible mechanism for the anti-tumorigenic effect of EPSs in cancer cells and provides insights into the biological pathways through which EPSs act. Moreover, it paves the way for new prospective cancer therapeutics as anti-miRNA.

Silibinin improves nonalcoholic fatty liver by regulating the expression of miR‑122: An in vitro and in vivo study

Silibinin is a flavonoid that improves fatty liver and insulin resistance. To elucidate the effect of silibinin on lipid deposition and the potential molecular mechanism, the present study conducted in vivo and in vitro experiments. In the in vivo experiments, mice were randomly divided into control, high‑fat and silibinin groups, while HepG2 cells were randomly divided into control, palmitic acid intervention and silibinin intervention groups. The mRNA, protein and miR‑122 expression associated with hepatic lipid metabolism were detected in each group. The results demonstrated that silibinin reduced the triglyceride content, miR‑122 expression and the mRNA and protein expressions of fatty acid synthase (FAS) and acetyl‑CoA carboxylase (ACC). Silibinin increased the mRNA and protein expression of carnitine palmitoyl transferase 1A (CPT1A). In the present study, HepG2 cells cultured with palmitate were treated with silibinin following overexpression of micro RNA (miR) 122. The results demonstrated that the mRNA and protein expression of FAS and ACC was increased, while that of CPT1A was decreased. Therefore, it could be deduced that silibinin improved lipid metabolism by reducing the expression of miR‑122 and inhibiting the expression of miR‑122 may be a new therapeutic target to improve fatty liver disease.

Regulation of microRNA-21 expression by natural products in cancer

Natural products have been of much interest in research studies owing to their wide pharmacological applications, chemical diversity, low side effects, and multitarget activities. Examples of these compounds include matrine, sulforaphane, silibinin, curcumin, berberin, resveratrol, and quercetin. Some of the present anticancer drugs, such as taxol, vincristine, vinblastine, and doxorubicin are also derived from natural products. The anti-carcinogenic effects of these products are partly mediated through modulation of microRNA-21 (miR-21) expression. To date, numerous downstream targets of miR-21 have been recognized, which include phosphatase and tensin homolog (PTEN), ras homolog gene family member B (RHOB), phosphoinositide 3-kinase/protein kinase B (PI3K/Akt), programmed cell death 4 (PDCD4), signal transducer and activator of transcription (STAT)-3, and nuclear factor kappa B (NF-κB) pathways. These signaling pathways, their regulation by oncomiR-21 in cancer, and the modulating impact of natural products are the main focus of this review.

Inflammation as a risk factor for stroke in atrial fibrillation: data from a microarray data analysis

Objective

Stroke is a severe complication of atrial fibrillation (AF). We aimed to discover key genes and microRNAs related to stroke risk in patients with AF using bioinformatics analysis.

Methods

GSE66724 microarray data, including peripheral blood samples from eight patients with AF and stroke and eight patients with AF without stroke, were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between AF patients with and without stroke were identified using the GEO2R online tool. Functional enrichment analysis was performed using the DAVID database. A protein–protein interaction (PPI) network was obtained using the STRING database. MicroRNAs (miRs) targeting these DEGs were obtained from the miRNet database. A miR–DEG network was constructed using Cytoscape software.

Results

We identified 165 DEGs (141 upregulated and 24 downregulated). Enrichment analysis showed enrichment of certain inflammatory processes. The miR–DEG network revealed key genes, including MEF2A, CAND1, PELI1, and PDCD4, and microRNAs, including miR-1, miR-1-3p, miR-21, miR-21-5p, miR-192, miR-192-5p, miR-155, and miR-155-5p.

Conclusion

Dysregulation of certain genes and microRNAs involved in inflammation may be associated with a higher risk of stroke in patients with AF. Evaluating these biomarkers could improve prediction, prevention, and treatment of stroke in patients with AF.

Inhibitory effect of flavonoid xanthomicrol on triple-negative breast tumor via regulation of cancer-associated microRNAs

Breast cancer is the leading cause of cancer death in women worldwide. Due to the side effects of current chemo-reagents on healthy tissues, it is essential to search for alternative compounds with less toxicity and better efficacy. In the present study, we have investigated the anticancer effects of flavonoid xanthomicrol on the mice breast cancer model using MTT assay, cell cycle and Annexin/PI analysis, colony formation assay, H&E staining, immunohistochemistry, and miRNA analysis. Our results demonstrated that xanthomicrol decreased the cell viability and clonogenic capability, induced G1-arrest and apoptosis in the breast cancer cells in vitro, and caused a significant reduction in the volume and weight of mice tumors in vivo. In addition, xanthomicrol reduced the expression of TNFα, VEGF, MMP9, and Ki67, while upregulating the expression of apoptotic markers such as Bax, caspase3, and caspase9. Finally, the expression of miR21, miR27, and miR125, known as oncomirs, decreased significantly after xanthomicrol administration, while the expression of miR29 and miR34, functioning as tumor suppressors, increased significantly (p < .001). Our data demonstrated that xanthomicrol can induce apoptosis and suppress angiogenesis in breast cancer cells due to its inhibitory effect on oncomirs and its stimulatory effect on tumor suppressor miRNAs.

Participation of MicroRNAs in the Treatment of Cancer with Phytochemicals

Cancer is a global health concern and one of the main causes of disease-related death. Even with considerable progress in investigations on cancer therapy, effective anti-cancer agents and regimens have thus far been insufficient. There has been compelling evidence that natural phytochemicals and their derivatives have potent anti-cancer activities. Plant-based anti-cancer agents, such as etoposide, irinotecan, paclitaxel, and vincristine, are currently being applied in medical treatments for patients with cancer. Further, the efficacy of plenty of phytochemicals has been evaluated to discover a promising candidate for cancer therapy. For developing more effective cancer therapy, it is required to apprehend the molecular mechanism deployed by natural compounds. MicroRNAs (miRNAs) have been realized to play a pivotal role in regulating cellular signaling pathways, affecting the efficacy of therapeutic agents in cancer. This review presents a feature of phytochemicals with anti-cancer activity, focusing mainly on the relationship between phytochemicals and miRNAs, with insights into the role of miRNAs as the mediators and the regulators of anti-cancer effects of phytochemicals.

Natural compounds modulate the crosstalk between apoptosis- and autophagy-regulated signaling pathways: Controlling the uncontrolled expansion of tumor cells

Due to the high number of annual cancer-related deaths, and the economic burden that this malignancy affects today's society, the study of compounds isolated from natural sources should be encouraged. Most cancers are the result of a combined effect of lifestyle, environmental factors, and genetic and hereditary components. Recent literature reveals an increase in the interest for the study of phytochemicals from traditional medicine, this being a valuable resource for modern medicine to identify novel bioactive agents with potential medicinal applications. Phytochemicals are components of traditional medicine that are showing promising application in modern medicine due to their antitumor activities. Recent studies regarding two major mechanisms underlying cancer development and regulation, apoptosis and autophagy, have shown that the signaling pathways of both these processes are significantly interconnected through various mechanisms of crosstalk. Phytochemicals are able to activate pro-autophagic and pro-apoptosis mechanisms. Understanding the molecular mechanism involved in apoptosis-autophagy relationship modulated by phytochemicals plays a key role in development of a new therapeutic strategy for cancer treatment. The purpose of this review is to outline the bioactive properties of the natural phytochemicals with validated antitumor activity, focusing particularly on their role in the regulation of apoptosis and autophagy crosstalk that triggers the uncontrolled expansion of tumor cells. Furthermore, we have also critically discussed the limitations and challenges of existing research strategies and the prospective research directions in this field.

Apoptosis induction and proliferation inhibition by silibinin encapsulated in nanoparticles in MIA PaCa-2 cancer cells and deregulation of some miRNAs

OBJECTIVES

Silibinin, as an herbal compound, has anti-cancer activity. Because of low solubility of silibinin in water and body fluids, it was encapsulated in polymersome nanoparticles and its effects were evaluated on pancreatic cancer cells and cancer stem cells.

MATERIALS AND METHODS

MIA PaCa-2 pancreatic cancer cells were treated with different doses of silibinin encapsulated in polymersome nanoparticles (SPNs). Stemness of MIA PaCa-2 cells was evaluated by hanging drop technique and CD133, CD24, and CD44 staining. The effects of SPNs on cell cycle, apoptosis and the expression of several genes and miRNAs were investigated.

RESULTS

IC50 of SPNs was determined to be 40 µg/ml after 24 hr. Our analysis showed that >98% of MIA PaCa-2 cells expressed three stem cell markers. FACS analysis showed a decrease in these markers in SPNs-treated cells. PI/AnnexinV staining revealed that 40 µg/ml and 50 µg/ml of SPNs increased apoptosis up to ~40% and >80% of treated cells, respectively. Upregulation of miR-34a, miR-126, and miR-let7b and downregulation of miR-155, miR-222 and miR-21 was observed in SPNs-treated cells. In addition, downregulation of some genes involved in proliferation or migration such as AKT3, MASPINE, and SERPINEA12, and upregulation of apoptotic genes were observed in treated cells.

CONCLUSION

Our results suggested that SPNs induced apoptosis and inhibited migration and proliferation in pancreatic cells and cancer stem cells through suppression of some onco-miRs and induction of some tumor suppressive miRs, as well as their targets.

Role of natural compounds in preventing and treating breast cancer

Breast cancer (BrCa) is the most commonly diagnosed cancer and the second leading cause of cancer-related death in women. Alarming increases in the cases quests for more effective treatment of BrCa. As most chemotherapeutic drugs are associated with drug resistance, cancer relapse, and side effects, scientists are turning to agents with more efficacy, such as natural compounds for treatment and prevention of BrCa. Selected natural compounds, substances derived from living organisms, promote apoptosis and inhibit metastasis, preventing cancer growth. As a result, these compounds have the potential to suppress BrCa progression, thus increasing patient survival rates and decreasing the number of BrCa-related deaths. In this review, we summarize natural compounds that have displayed, anti-cancer effects on BrCa cells in various studies. These natural compounds inhibit the development of BrCa, suppress the growth of cancer cells, and promote cell death. We conclude that natural compounds are efficient, effective and promising agents for treating BrCa other than therapeutic methods.

Flavonolignans: One Step Further in the Broad-Spectrum Approach of Cancer

BACKGROUND

The small chemical class of flavonolignans encompasses unique hybrid molecules with versatile biological activities. Their anticancer effects have received considerable attention, and a large body of supporting evidence has accumulated. Moreover, their ability to interact with proteins involved in drug resistance, and to enhance the effects of conventional chemotherapeutics in decreasing cell viability make them influential partners in addressing cancer.

OBJECTIVE

The review provides an outline of the various ways in which flavonolignans advance the combat against cancer. While the main focus falls on flavonolignans from milk thistle, attention is drawn to the yet, underexplored potential of less known flavonolignan subgroups derived from isoflavonoids and aurones.

METHODS

Proceeding from the presentation of natural flavonolignan subtypes and their occurrence, the present work reviews these compounds with regard to their molecular targets in cancer, anti-angiogenetic effects, synergistic efficacy in conjunction with anticancer agents, reversal of drug resistance, and importance in overcoming the side effects of anticancer therapy. Recent advances in the endeavor to improve flavonolignan bioavailability in cancer are also presented.

CONCLUSIONS

Significant progress has been achieved in detailing the molecular mechanisms of silybin and its congeners in experimental models of cancer. The availability of novel formulations with improved bioavailability, and data from phase I clinical trials in cancer patients provide an encouraging basis for more extensive trials aimed at evaluating the benefits of Silybum flavonolignans in cancer management. On the other hand, further research on the antitumor efficacy of iso-flavonolignans and other subtypes of flavonolignans should be pursued.

Modulation of Multiple Signaling Pathways of the Plant-Derived Natural Products in Cancer

Natural compounds are highly effective anticancer chemotherapeutic agents, and the targets of plant-derived anticancer agents have been widely reported. In this review, we focus on the main signaling pathways of apoptosis, proliferation, invasion, and metastasis that are regulated by polyphenols, alkaloids, saponins, and polysaccharides. Alkaloids primarily affect apoptosis-related pathways, while polysaccharides primarily target pathways related to proliferation, invasion, and metastasis. Other compounds, such as flavonoids and saponins, affect all of these aspects. The association between compound structures and signaling pathways may play a critical role in drug discovery.

Perspective: Therapeutic Potential of Flavonoids as Alternative Medicines in Epilepsy

Epilepsy is a chronic neurological disorder that affects many people worldwide. Temporal lobe epilepsy is the most common and most studied type of epilepsy, but the pathological mechanisms underlying this condition are poorly understood. More than 20 antiepileptic drugs (AEDs) have been developed and used for the treatment of epilepsy; however, 30% of patients still experience uncontrolled epilepsy and associated comorbidities, which impair their quality of life. In addition, various side effects have been reported for AEDs, such as drowsiness, unsteadiness, dizziness, blurred or double vision, tremor (shakiness), greater risk of infections, bruising, and bleeding. Thus, critical medical needs remain unmet for patients with uncontrolled epilepsy. Flavonoids belong to a subclass of polyphenols that are widely present in fruits, vegetables, and certain beverages. Recently, many studies have reported that some flavonoids elicit various beneficial effects in patients with epilepsy without causing the side effects associated with conventional medical therapies. Moreover, flavonoids may have a property of regulating microRNA expression associated with inflammation and cell survival. These findings suggest that flavonoids, which are more effective but impose fewer adverse effects than conventional AEDs, could be used in the treatment of epilepsy.

Silibinin encapsulation in polymersome: A promising anticancer nanoparticle for inducing apoptosis and decreasing the expression level of miR-125b/miR-182 in human breast cancer cells

Silibinin, a polyphenolic flavonolignan, is well-known as a safe therapeutic drug without any side effects in the treatment of many malignancies especially cancerous cells. In this study, to overcome problems such as low solubility of silibinin and to enhance its delivery to cancerous cells, we encapsulated silibinin in polymersome nanoparticles. Physicochemical measurements such as dynamic light scattering, transmission electron microscopy, scanning electron microscopy, and atomic force microscopy confirmed the proper encapsulation of silibinin in nanoparticles. Furthermore, antiproliferative and apoptotic activities of silibinin encapsulated in polymersome nanoparticles (SPNs) on MDA-MB-231 breast cancer cell line were validated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Annexin V/Propidium Iodide measurement, and cell cycle analysis. In addition, quantitative reverse transcription polymerase chain reaction analysis confirmed that SPNs can repress oncogenic microRNAs (miRNAs) such as miR-125b and miR-182, as well as antiapoptotic genes such as Bcl2. SPNs can also induce overexpression of proapoptotic target genes such as P53, CASP9, and BAX directly and/or indirectly (through regulation of miRNAs). Our results suggested that polymersomes can be used as stable carriers in nano-dimensions and SPNs can be considered as a promising pharmacological agent for cancer therapy.

Oncogenic and Tumor-Suppressive Roles of MicroRNAs with Special Reference to Apoptosis: Molecular Mechanisms and Therapeutic Potential

MicroRNAs (miRNAs) are the non-coding class of minute RNA molecules that negatively control post-transcriptional regulation of various functional genes. These miRNAs are transcribed from the loci present in the introns of functional or protein-coding genes, exons of non-coding genes, or even in the 3'-untranslated region (3'-UTR). They have potential to modulate the stability or translational efficiency of a variety of target RNA [messenger RNA (mRNA)]. The regulatory function of miRNAs has been elucidated in several pathological conditions, including neurological (Alzheimer's disease and Parkinson's disease) and cardiovascular conditions, along with cancer. Importantly, miRNA identification in cancer progression and invasion has evolved as an incipient era in cancer treatment. Several studies have shown the influence of miRNAs on various cancer processes, including apoptosis, invasion, metastasis and angiogenesis. In particular, apoptosis induction in tumor cells through miRNA has been extensively studied. The biphasic mode (up- and down-regulation) of miRNA expression in apoptosis and other cancer processes has already been determined. The findings of these studies could be utilized to develop potential therapeutic strategies for the management of various cancers. The present review critically describes the oncogenic and tumor suppressor role of miRNAs in apoptosis and other cancer processes, therapy resistance, and use of their presence in the body fluids as biomarkers.

Mechanistic evaluation of phytochemicals in breast cancer remedy: current understanding and future perspectives

Breast cancer is one of the most commonly diagnosed cancers around the globe and accounts for a large proportion of fatalities in women. Despite the advancement in therapeutic and diagnostic procedures, breast cancer still represents a major challenge. Current anti-breast cancer approaches include surgical removal, radiotherapy, hormonal therapy and the use of various chemotherapeutic drugs. However, drug resistance, associated serious adverse effects, metastasis and recurrence complications still need to be resolved which demand safe and alternative strategies. In this scenario, phytochemicals have recently gained huge attention due to their safety profile and cost-effectiveness. These phytochemicals modulate various genes, gene products and signalling pathways, thereby inhibiting breast cancer cell proliferation, invasion, angiogenesis and metastasis and inducing apoptosis. Moreover, they also target breast cancer stem cells and overcome drug resistance problems in breast carcinomas. Phytochemicals as adjuvants with chemotherapeutic drugs have greatly enhanced their therapeutic efficacy. This review focuses on the recently recognized molecular mechanisms underlying breast cancer chemoprevention with the use of phytochemicals such as curcumin, resveratrol, silibinin, genistein, epigallocatechin gallate, secoisolariciresinol, thymoquinone, kaempferol, quercetin, parthenolide, sulforaphane, ginsenosides, naringenin, isoliquiritigenin, luteolin, benzyl isothiocyanate, α-mangostin, 3,3'-diindolylmethane, pterostilbene, vinca alkaloids and apigenin.

Simultaneous downregulation of miR-21 and miR-155 through oleuropein for breast cancer prevention and therapy

Breast cancer (BC) is the leading cause of cancer mortality in women worldwide. It recently was proven that miRNAs play a critical role in BC development. The use of natural agents for control of cancer by modulating miRNAs is promising. Oleuropein is a natural polyphenolic agent with anti-neoplastic properties and is well tolerated by humans. This study was undertaken to determine the therapeutic effects of oleuropein through modulation of master oncomiRs (miR-21 and miR-155) in BC cells. The present study provides the first link between miRNA and oleuropein as a mechanism in BC. MCF-7 cells were tested with and without oleuropein and the cell viability, apoptosis, and migration were examined. The effect of oleuropein on miR-21 and miR-155 expression was assessed through qRT-PCR. It was found that oleuropein induced apoptosis and retarded cell migration and invasion in a dose-dependent manner in the human MCF7 BC cell line. It was observed that oleuropein significantly decreased expression of both miR-21 and miR-155 over time in a dose-dependent manner. These results demonstrate that oleuropein is a potential therapeutic and preventive agent for BC. Oleuropein exhibits an anti-cancer effect by modulation of tumor suppressor gene expression, which is targeted by oncomiRs.

Analysis of the microRNA expression profiles in DEF cells infected with duck Tembusu virus

Duck Tembusu virus (DTMUV), belonging to the Flaviviridae family, is a single-stranded positive-sense RNA virus. Since April 2010, the outbreak of DTMUV in southeast provinces of China has caused great economic losses. MicroRNAs (miRNAs) play important regulatory roles in viral infection through binding to the host target genes or the viral genomes. To better understanding the molecular mechanisms of virus-host interaction, here we identified the miRNA expression profiles in DTMUV-infected and uninfected DEF cells by high-throughput sequencing. A total of 287 known and 63 novel miRNAs were identified. 48 miRNAs, including 26 known miRNAs and 22 novel miRNAs, were differentially expressed in response to DTMUV infection. Among these miRNAs, 37 miRNAs were up-regulated and 11 miRNAs were down-regulated. 9 miRNAs were randomly selected for validation by qRT-PCR experiment. The results of qRT-PCR experiment were consistent with the sequencing data. GO enrichment showed that the predicted targets of these differentially expressed miRNAs were mainly involved in the regulation of immune system, cellular process and metabolic process. KEGG pathways analysis showed that predicted target genes were involved in several signaling pathways such as Wnt signaling pathway, TGF-beta signaling pathway, mTOR signaling pathway and FoxO signaling pathway. This is the first study to evaluate changes of miRNA expression in DEF cells upon DTMUV infection. Our findings provide important clues for better understanding the DTMUV-host interaction.

Negative Regulation of PTEN by MicroRNA-221 and Its Association with Drug Resistance and Cellular Senescence in Lung Cancer Cells

Objective

Chemotherapy is the routine method for treating many cancers, but long-term treatment may result in developing resistance to the drugs. The aim of this study was to identify whether noncoding RNAs play a role in drug resistance and how they affect drug resistance.

Materials and Methods

The expression levels of miR-221 in different lung cancer cell lines H226, H1299, and A549 were measured. H1299 and A549 cell lines were transfected to overexpress and downexpress miR-221, and cell viability and cell senescence were determined. The PTEN/Akt pathway was then examined by real-time polymerase chain reaction and Western blot analysis.

Results

MiR-221 together with proteins MDR1 and ABCG2 was upregulated in Cisplatin-resistant A549 lung cancer cells. Anti-miR-221 inhibits proliferation and induces senescence in lung cancer cells. PTEN/Akt pathway axis was identified as a target of drug resistance induced by miR-221.

Conclusion

Our results revealed that miR-221 is an important regulator for chemotherapy sensitivity and showed miR-221 as a potential target for drug sensitization.

The role of NFκB in spheroid formation of human breast cancer cells cultured on the Random Positioning Machine

Human MCF-7 breast cancer cells were exposed to a Random Positioning Machine (RPM). After 24 hours (h) the cells grew either adherently within a monolayer (AD) or within multicellular spheroids (MCS). AD and MCS populations were separately harvested, their cellular differences were determined performing qPCR on genes, which were differently expressed in AD and MCS cells. Gene array technology was applied to detect RPM-sensitive genes in MCF-7 cells after 24 h. Furthermore, the capability to form multicellular spheroids in vitro was compared with the intracellular distribution of NF-kappaB (NFκB) p65. NFκB was equally distributed in static control cells, but predominantly localized in the cytoplasm in AD cells and nucleus in MCS cells exposed to the RPM. Gene array analyses revealed a more than 2-fold change of only 23 genes including some whose products are affected by oxygen levels or regulate glycolysis. Significant upregulations of the mRNAs of enzymes degrading heme, of ANXA1, ANXA2, CTGF, CAV2 and ICAM1, as well as of FAS, Casp8, BAX, p53, CYC1 and PARP1 were observed in MCS cells as compared with 1g-control and AD cells. An interaction analysis of 47 investigated genes suggested that HMOX-1 and NFκB variants are activated, when multicellular spheroids are formed.

miR-155 regulates high glucose-induced cardiac fibrosis via the TGF-β signaling pathway

Cardiac fibrosis, as a pathological process, plays an important role in various cardiac diseases. microRNA-155 (miR-155) is one of the most important miRNAs, and previous studies have shown that it is a regulatory factor in various fibrotic diseases. However, the mechanism by which miR-155 affects myocardial fibrosis remains unclear. In this study, we aim to establish the biological function of miR-155 in myocardial fibrosis induced by diabetes in mice. We used normal C57BL/6 wild type (WT) and miR-155 knockout (KO) mice to establish the diabetic model by intraperitoneal injection of streptozotocin, and we utilized echocardiography to evaluate the cardiac function at 30 and 60 days post-modeling. Hematoxylin-eosin (HE) and sirius-red (SR) staining were used to evaluate the degree of myocardial lesions. Furthermore, we extracted cardiac fibroblasts (CFs) from the WT mice and transfected them with miR-155 inhibitors, mimics and negative control siRNAs to analyze the specific mechanism involved in the development of myocardial fibrosis. The results showed that miR-155 deficiency could prevent cardiac fibrosis induced by diabetes in mice and also that attenuated collagen synthesis is induced by high glucose (HG) in CFs. We found that miR-155 regulated cardiac fibrosis via the TGF-β1-Smad 2 signaling pathway. These findings suggest that miR-155 may be a therapeutic target for preventing cardiac fibrosis induced by diabetes.

Effects of miR-21 downregulation and silibinin treatment in breast cancer cell lines

Silibinin is a natural polyphenol with high antioxidant and anticancer properties, which causes cell cycle arrest and apoptosis in most cancer cell types including breast cancer, but the in-line mechanisms, are still unknown. Silibinin significantly downregulated oncomiR miR-21 expression in breast cancer cells. Here the effect of anti-miR-21 on cell viability, apoptotic induction, cell cycle distribution, and the expression levels of downstream targets of miR-21 were investigated in MCF-7 and T47D cells. MiR-21 mimic transfection was also applied in silibinin treated samples to evaluate functional role of miR-21downregulation on silibinin effects. It was found that after anti-miR-21 transfection, no significant changes were detected in cell viability, apoptosis (except early apoptosis), and cell cycle in MCF-7 and T47D cells. Compared to silibinin, miR-21 mimic transfection in combination with silibinin caused a slight modulation in some of the examined silibinin effects including apoptosis, Bcl2 mRNA and PTEN mRNA and protein levels. Silibinin slightly changed luciferase activity from reporters containing the miR-21 recognition elements from PTEN-3'UTR and Bcl2-3'UTR in both cell lines. Together these data demonstrated negligible cancer-progression impact of miR-21 and limited roles of miR-21 downregulation in examined silibinin effects, and strengthened the anti-cancer pathways of silibinin other than miR-21downregulation in MCF-7 and T47D cells.

A comparative study of the characterization of miR-155 in knockout mice

miR-155 is one of the most important miRNAs and plays a very important role in numerous biological processes. However, few studies have characterized this miRNA in mice under normal physiological conditions. We aimed to characterize miR-155 in vivo by using a comparative analysis. In our study, we compared miR-155 knockout (KO) mice with C57BL/6 wild type (WT) mice in order to characterize miR-155 in mice under normal physiological conditions using many evaluation methods, including a reproductive performance analysis, growth curve, ultrasonic estimation, haematological examination, and histopathological analysis. These analyses showed no significant differences between groups in the main evaluation indices. The growth and development were nearly normal for all mice and did not differ between the control and model groups. Using a comparative analysis and a summary of related studies published in recent years, we found that miR-155 was not essential for normal physiological processes in 8-week-old mice. miR-155 deficiency did not affect the development and growth of naturally ageing mice during the 42 days after birth. Thus, studying the complex biological functions of miR-155 requires the further use of KO mouse models.

MicroRNAs regulate the epithelial-mesenchymal transition and influence breast cancer invasion and metastasis

MicroRNAs are small RNA molecules that play a major role in the post-transcriptional regulation of genes and influence the development, differentiation, proliferation, and apoptosis of cells and the development and progression of tumors. The epithelial-mesenchymal transition is a process by which epithelial cells morphologically transform into cells with a mesenchymal phenotype. The epithelial-mesenchymal transition plays a highly important role in tumor invasion and metastasis. Increasing evidence indicates that microRNAs are tightly associated with epithelial-mesenchymal transition regulation in tumor cells. In breast cancer, various microRNA molecules have been identified as epithelial-mesenchymal transition inducers or inhibitors, which, through different mechanisms and signaling pathways, participate in the regulation of breast cancer invasion and metastasis among various biological behaviors. The epithelial-mesenchymal transition-related microRNAs in breast cancer provide valuable molecules for researching cell invasion and metastasis, and they also provide candidate targets that may be significant for the targeted therapy of breast cancer.

Identification of MicroRNAs as Breast Cancer Prognosis Markers through the Cancer Genome Atlas

Breast cancer is the second-most common cancer and second-leading cause of cancer mortality in American women. The dysregulation of microRNAs (miRNAs) plays a key role in almost all cancers, including breast cancer. We comprehensively analyzed miRNA expression, global gene expression, and patient survival from the Cancer Genomes Atlas (TCGA) to identify clinically relevant miRNAs and their potential gene targets in breast tumors. In our analysis, we found that increased expression of 12 mature miRNAs-hsa-miR-320a, hsa-miR-361-5p, hsa-miR-103a-3p, hsa-miR-21-5p, hsa-miR-374b-5p, hsa-miR-140-3p, hsa-miR-25-3p, hsa-miR-651-5p, hsa-miR-200c-3p, hsa-miR-30a-5p, hsa-miR-30c-5p, and hsa-let-7i-5p -each predicted improved breast cancer survival. Of the 12 miRNAs, miR-320a, miR-361-5p, miR-21-5p, miR-103a-3p were selected for further analysis. By correlating global gene expression with miRNA expression and then employing miRNA target prediction analysis, we suggest that the four miRNAs may exert protective phenotypes by targeting breast oncogenes that contribute to patient survival. We propose that miR-320a targets the survival-associated genes RAD51, RRP1B, and TDG; miR-361-5p targets ARCN1; and miR-21-5p targets MSH2, RMND5A, STAG2, and UBE2D3. The results of our stringent bioinformatics approach for identifying clinically relevant miRNAs and their targets indicate that miR-320a, miR-361-5p, and miR-21-5p may contribute to breast cancer survival.

The role of microRNAs in resistance to targeted treatments of non-small cell lung cancer

PURPOSE

Non-small cell lung cancer (NSCLC), accounting for the most of lung cancers, is usually diagnosed in advanced stage. Targeted treatments boost advanced NSCLC patients with certain mutations, but early drug resistance blocks the advantages of target medicine. MicroRNAs (miRNAs) are regarded as a cluster of small noncoding and posttranscriptionally negative regulating RNAs. We want to explore the role of miRNAs in resistance to targeted treatments of NSCLC to improve the prognosis.

METHODS

We reviewed recent studies about miRNAs and targeted treatment resistance in NSCLC and classified resistance into two types: EGFR-TKIs resistance and ALK-TKIs resistance.

RESULTS AND CONCLUSION

Recent studies indicate that miRNAs involve in drug resistance possession in positive and negative manners. Inhibiting expression of certain miRNAs that promote drug resistance and increasing expression of miRNAs that reverse drug resistance may illuminate novel prospect of adjuvant targeted treatments in NSCLC.

Silibinin: a potential old drug for cancer therapy

INTRODUCTION

Silibinin is mixture of flavonolignans extracted from milk thistle and often has been used in the treatment of acute and chronic liver disorders caused by toxins, drug, alcohol and hepatitis and gall bladder disorders for its antioxidant and hepatoprotective properties. Areas covered: However, increasing evidence suggest that silibinin is not solely limited in the treatment of these diseases. Further research suggests that silymarin may function diversely and may serve as a novel therapy for cancer therapy, such as lung cancer, prostatic cancer, colon cancer, breast cancer, bladder cancer and hepatocellular carcinoma by regulating cancer cells growth, proliferation, apoptosis, angiogenesis and many other mechanism. Expert commentary: In this review, in order to provide potential new treatment for these cancer, we summarize the recent anti-cancer findings of silibinin in these cancer and clarify the mechanisms of this effect.