MicroRNA-34a: Potent Tumor Suppressor, Cancer Stem Cell Inhibitor, and Potential Anticancer Therapeutic

Hallmarks of cancer resistance

This review explores the hallmarks of cancer resistance, including drug efflux mediated by ATP-binding cassette (ABC) transporters, metabolic reprogramming characterized by the Warburg effect, and the dynamic interplay between cancer cells and mitochondria. The role of cancer stem cells (CSCs) in treatment resistance and the regulatory influence of non-coding RNAs, such as long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), are studied. The chapter emphasizes future directions, encompassing advancements in immunotherapy, strategies to counter adaptive resistance, integration of artificial intelligence for predictive modeling, and the identification of biomarkers for personalized treatment. The comprehensive exploration of these hallmarks provides a foundation for innovative therapeutic approaches, aiming to navigate the complex landscape of cancer resistance and enhance patient outcomes.

Selective targeting of chemically modified miR-34a to prostate cancer using a small molecule ligand and an endosomal escape agent

Use of tumor-suppressive microRNAs (miRNAs) as anti-cancer agents is hindered by the lack of effective delivery vehicles, entrapment of the miRNA within endocytic compartments, and rapid degradation of miRNA by nucleases. To address these issues, we developed a miRNA delivery strategy that includes (1) a targeting ligand, (2) an endosomal escape agent, nigericin and (3) a chemically modified miRNA. The delivery ligand, DUPA (2-[3-(1,3-dicarboxy propyl) ureido] pentanedioic acid), was selected based on its specificity for prostate-specific membrane antigen (PSMA), a receptor routinely upregulated in prostate cancer-one of the leading causes of cancer death among men. DUPA was conjugated to the tumor suppressive miRNA, miR-34a (DUPA-miR-34a) based on the ability of miR-34a to inhibit prostate cancer cell proliferation. To mediate endosomal escape, nigericin was incorporated into the complex, resulting in DUPA-nigericin-miR-34a. Both DUPA-miR-34a and DUPA-nigericin-miR-34a specifically bound to, and were taken up by, PSMA-expressing cells in vitro and in vivo. And while both DUPA-miR-34a and DUPA-nigericin-miR-34a downregulated miR-34a target genes, only DUPA-nigericin-miR-34a decreased cell proliferation in vitro and delayed tumor growth in vivo. Tumor growth was further reduced using a fully modified version of miR-34a that has significantly increased stability.

CD44 and its implication in neoplastic diseases

CD44, a nonkinase single span transmembrane glycoprotein, is a major cell surface receptor for many other extracellular matrix components as well as classic markers of cancer stem cells and immune cells. Through alternative splicing of CD44 gene, CD44 is divided into two isoforms, the standard isoform of CD44 (CD44s) and the variant isoform of CD44 (CD44v). Different isoforms of CD44 participate in regulating various signaling pathways, modulating cancer proliferation, invasion, metastasis, and drug resistance, with its aberrant expression and dysregulation contributing to tumor initiation and progression. However, CD44s and CD44v play overlapping or contradictory roles in tumor initiation and progression, which is not fully understood. Herein, we discuss the present understanding of the functional and structural roles of CD44 in the pathogenic mechanism of multiple cancers. The regulation functions of CD44 in cancers-associated signaling pathways is summarized. Moreover, we provide an overview of the anticancer therapeutic strategies that targeting CD44 and preclinical and clinical trials evaluating the pharmacokinetics, efficacy, and drug-related toxicity about CD44-targeted therapies. This review provides up-to-date information about the roles of CD44 in neoplastic diseases, which may open new perspectives in the field of cancer treatment through targeting CD44.

miRNAs in pancreatic cancer progression and metastasis

Small non-coding RNA or microRNA (miRNA) are critical regulators of eukaryotic cells. Dysregulation of miRNA expression and function has been linked to a variety of diseases including cancer. They play a complex role in cancers, having both tumour suppressor and promoter properties. In addition, a single miRNA can be involved in regulating several mRNAs or many miRNAs can regulate a single mRNA, therefore assessing these roles is essential to a better understanding in cancer initiation and development. Pancreatic cancer is a leading cause of cancer death worldwide, in part due to the lack of diagnostic tools and limited treatment options. The most common form of pancreatic cancer, pancreatic ductal adenocarcinoma (PDAC), is characterised by major genetic mutations that drive cancer initiation and progression. The regulation or interaction of miRNAs with these cancer driving mutations suggests a strong link between the two. Understanding this link between miRNA and PDAC progression may give rise to novel treatments or diagnostic tools. This review summarises the role of miRNAs in PDAC, the downstream signalling pathways that they play a role in, how these are being used and studied as therapeutic targets as well as prognostic/diagnostic tools to improve the clinical outcome of PDAC.

The Evaluation of a 5-miRNA Panel in Patients with Periodontitis Disease

INTRODUCTION

Side by side with tooth decay, periodontitis remains one of the most common oral diseases and is increasingly recognized as a serious public health concern worldwide.

OBJECTIVES

The present study aims at comparing the levels of 5 specific miRNAs (miR-29b-3p, miR-34a-5p, miR-155-5p, miR-181a-5p, and miR-192-5p) in patients with periodontal disease and healthy controls.

METHODS

The pathogenic mechanism is related to the activation of immune response and significant alteration of coding and noncoding genes, including miRNA. The study includes 50 subjects (17 with periodontal disease and 33 healthy controls) with a mean age of 45.3 y. In both periodontitis patients and healthy controls, a panel of 5 miRNAs (miR-29b-3p, miR-34a-5p, miR-155-5p, miR-181a-5p, and miR-192-5p) is examined by determining their expression levels with quantitative reverse transcription polymerase chain reaction.

RESULTS

The periodontitis patients express high levels of all the investigated miRNAs. Receiver operating characteristic curve analysis shows an area under the curve (AUC) of 0.69 to 0.74 for individual transcripts with the highest AUC value observed for miR-192, followed by miR-181a.

CONCLUSIONS

The study indicates that the 5-miRNA panel can be used as biomarker for periodontitis. In this way, all implantology procedures and treatment options for patients diagnosed with periodontitis can be improved for better long-term results, predictability, and follow-up frequency.

KNOWLEDGE TRANSFER STATEMENT

The discovery of a miRNA panel as a potential biomarker for periodontitis offers major opportunities for practical application. Our study can improve diagnostic accuracy; researchers can develop new theories on molecular mechanisms and biomarker discovery.

How MicroRNAs Command the Battle against Cancer

MicroRNAs (miRNAs) are small RNA molecules that regulate more than 30% of genes in humans. Recent studies have revealed that miRNAs play a crucial role in tumorigenesis. Large sets of miRNAs in human tumors are under-expressed compared to normal tissues. Furthermore, experiments have shown that interference with miRNA processing enhances tumorigenesis. Multiple studies have documented the causal role of miRNAs in cancer, and miRNA-based anticancer therapies are currently being developed. This review primarily focuses on two key points: (1) miRNAs and their role in human cancer and (2) the regulation of tumor suppressors by miRNAs. The review discusses (a) the regulation of the tumor suppressor p53 by miRNA, (b) the critical role of the miR-144/451 cluster in regulating the Itch-p63-Ago2 pathway, and (c) the regulation of PTEN by miRNAs. Future research and the perspectives of miRNA in cancer are also discussed. Understanding these pathways will open avenues for therapeutic interventions targeting miRNA regulation.

The microRNA-34 Family and Its Functional Role in Lung Cancer

Lung cancer is one of the most common malignant tumors in humans and the leading cause of cancer-related deaths worldwide. The microRNA-34 (miR-34) family is dysregulated in various human cancers and is an important family of tumor suppressor genes among microRNAs. The miR-34 family is downregulated in lung cancer. It inhibits cell proliferation, metastasis, and invasion, arrests the cell cycle, and induces apoptosis or senescence by negatively regulating many oncogenes. It is commonly used to detect and treat lung cancer. This study describes the regulatory role of the miR-34 family in lung cancer and the associated research advances in treatment.

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

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

The Effect of Akkermansia muciniphila and Its Outer Membrane Vesicles on MicroRNAs Expression of Inflammatory and Anti-inflammatory Pathways in Human Dendritic Cells

Probiotics play a crucial role in immunomodulation by regulating dendritic cell (DC) maturation and inducing tolerogenic DCs. Akkermansia muciniphila affects inflammatory response by elevating inhibitory cytokines. We aimed to evaluate whether Akkermansia muciniphila and its outer membrane vesicles (OMVs) affect microRNA-155, microRNA-146a, microRNA-34a, and let-7i expression of inflammatory and anti-inflammatory pathways. Peripheral blood mononuclear cells (PBMCs) were isolated from the healthy volunteers. To produce DCs, monocytes were cultivated with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). DCs were allocated into six subgroups: DC + Lipopolysaccharide (LPS), DC + dexamethasone, DC + A. muciniphila (MOI 100, 50), DC + OMVs (50 µg/ml), and DC + PBS. The surface expression of human leukocyte antigen-antigen D related (HLA-DR), CD86, CD80, CD83, CD11c, and CD14 was examined using flow cytometry, and the expression of microRNAs was assessed using qRT-PCR, and the levels of IL-12 and IL-10 were measured using ELISA. A. muciniphila (MOIs 50, 100) could significantly decrease IL-12 levels relative to the LPS group. The IL-10 levels were decreased in the DC + LPS group than the DC + dexamethasone group. Treatment with A. muciniphila (MOI 100) and OMVs could elevate the concentrations of IL-10. DC treatment with LPS led to a significant increment in the expression of microRNA-155, microRNA-34a, and microRNA-146a. The expression of these microRNAs was reversed by A. muciniphilia and its OMVs treatment. Let-7i increased in treatment groups compared to the DC + LPS group. A. muciniphilia (MOI 50) had a substantial effect on the expression of HLA-DR, CD80, and CD83 on DCs. Therefore, DCs treatment with A. muciniphila led to induce tolerogenic DCs and the production of anti-inflammatory IL-10.

Impact of Long-Lasting Environmental Factors on Regulation Mediated by the miR-34 Family

The present review focuses on the interactions of newly emerging environmental factors with miRNA-mediated regulation. In particular, we draw attention to the effects of phthalates, electromagnetic fields (EMFs) and a disrupted light/dark cycle. miRNAs are small non-coding RNA molecules with a tremendous regulatory impact, which is usually executed via gene expression inhibition. To address the capacity of environmental factors to influence miRNA-mediated regulation, the miR-34 family was selected for its well-described oncostatic and neuro-modulatory properties. The expression of miR-34 is in a tissue-dependent manner to some extent under the control of the circadian system. There is experimental evidence implicating that phthalates, EMFs and the circadian system interact with the miR-34 family, in both lines of its physiological functioning. The inhibition of miR-34 expression in response to phthalates, EMFs and light contamination has been described in cancer tissue and cell lines and was associated with a decline in oncostatic miR-34a signalling (decrease in p21 expression) and a promotion of tumorigenesis (increases in Noth1, cyclin D1 and cry1 expressions). The effects of miR-34 on neural functions have also been influenced by phthalates, EMFs and a disrupted light/dark cycle. Environmental factors shifted the effects of miR-34 from beneficial to the promotion of neurodegeneration and decreased cognition. Moreover, the apoptogenic capacity of miR-34 induced via phthalate administration in the testes has been shown to negatively influence germ cell proliferation. To conclude, as the oncostatic and positive neuromodulatory functions of the miR-34 family can be strongly influenced by environmental factors, their interactions should be taken into consideration in translational medicine.

Developing Folate-Conjugated miR-34a Therapeutic for Prostate Cancer: Challenges and Promises

Prostate cancer (PCa) remains a common cancer with high mortality in men due to its heterogeneity and the emergence of drug resistance. A critical factor contributing to its lethality is the presence of prostate cancer stem cells (PCSCs), which can self-renew, long-term propagate tumors, and mediate treatment resistance. MicroRNA-34a (miR-34a) has shown promise as an anti-PCSC therapeutic by targeting critical molecules involved in cancer stem cell (CSC) survival and functions. Despite extensive efforts, the development of miR-34a therapeutics still faces challenges, including non-specific delivery and delivery-associated toxicity. One emerging delivery approach is ligand-mediated conjugation, aiming to achieve specific delivery of miR-34a to cancer cells, thereby enhancing efficacy while minimizing toxicity. Folate-conjugated miR-34a (folate-miR-34a) has demonstrated promising anti-tumor efficacy in breast and lung cancers by targeting folate receptor α (FOLR1). Here, we first show that miR-34a, a TP53 transcriptional target, is reduced in PCa that harbors TP53 loss or mutations and that miR-34a mimic, when transfected into PCa cells, downregulated multiple miR-34a targets and inhibited cell growth. When exploring the therapeutic potential of folate-miR-34a, we found that folate-miR-34a exhibited impressive inhibitory effects on breast, ovarian, and cervical cancer cells but showed minimal effects on and targeted delivery to PCa cells due to a lack of appreciable expression of FOLR1 in PCa cells. Folate-miR-34a also did not display any apparent effect on PCa cells expressing prostate-specific membrane antigen (PMSA) despite the reported folate's binding capability to PSMA. These results highlight challenges in the specific delivery of folate-miR-34a to PCa due to a lack of target (receptor) expression. Our study offers novel insights into the challenges and promises within the field and casts light on the development of ligand-conjugated miR-34a therapeutics for PCa.

Acacetin inhibited non-small-cell lung cancer (NSCLC) cell growth via upregulating miR-34a in vitro and in vivo

Acacetin, one of the flavonoid compounds, is a natural product found in various plants, including Silver birch, and Damiana. Previous studies showed that acacetin has anti-cancer effects on many kinds of cancer cells, however, the role of and the mechanisms of actions of acacetin on non-small cell lung cancer (NSCLC) cells is still not fully understood. Herein, we found that, in vitro, acacetin inhibited the proliferation, invasion, and migration of NSCLC cells, A549 and H460, in a dose-dependent manner. Meanwhile, flow cytometry assay results showed that acacetin induced G2/M phase cell cycle arrest, and apoptosis of NSCLC cells. In vivo, acacetin suppressed tumor formation of A549-xenografted nude mice model with no obvious toxicities. Western blotting results showed that the protein levels of cell cycle-related proteins cyclin B1, cyclin D, and anti-apoptotic protein Bcl-2 had decreased, while the apoptosis-related protein Bak had increased both in NSCLC cells and in A549-xenografted tumor tissues. For investigating the molecular mechanism behind the biological effects of acacetin on NSCLC, we found that acacetin induced the expression levels of tumor suppressor p53 both in vitro and in vivo. MicroRNA, miR-34a, the direct target of p53, has been shown anti-NSCLC proliferation effects by suppressing the expression of its target gene programmed death ligand 1 (PD-L1). We found that acacetin upregulated the expression levels of miR-34a, and downregulated the expression levels of PD-L1 of NSCLC cells in vitro and of tumors in vivo. In vitro, knockdown p53 expression by siRNAs reversed the induction effects of acacetin on miR34a expression and abolished the inhibitory activity of acacetin on NSCLC cell proliferation. Furthermore, using agomir and antagomir to overexpress and suppress the expression miR-34a in NSCLC cells was also examined. We found that miR-34a agomir showed similar effects as acacetin on A549 cells, while miR-34a antagomir could partially or completely reverse acacetin's effects on A549 cells. In vivo, intratumor injection of miR-34a antagomir could drastically suppress the anti-tumor formation effects of acacetin in A549-xenografted nude mice. Overall, our results showed that acacetin inhibits cell proliferation and induces cell apoptosis of NSCLC cells by regulating miR-34a.

Developing folate-conjugated miR-34a therapeutic for prostate cancer treatment: Challenges and promises

Prostate cancer (PCa) remains a common cancer with high mortality in men due to its heterogeneity and the emergence of drug resistance. A critical factor contributing to its lethality is the presence of prostate cancer stem cells (PCSCs), which can self-renew, long-term propagate tumors and mediate treatment resistance. MicroRNA-34a (miR-34a) has shown promise as an anti-PCSC therapeutic by targeting critical molecules involved in cancer stem cell (CSC) survival and functions. Despite extensive efforts, the development of miR-34a therapeutics still faces challenges, including non-specific delivery and delivery-associated toxicity. One emerging delivery approach is ligand-mediated conjugation, aiming to achieve specific delivery of miR-34a to cancer cells, thereby enhancing efficacy while minimizing toxicity. Folate-conjugated miR-34a (folate-miR-34a) has demonstrated promising anti-tumor efficacy in breast and lung cancers by targeting folate receptor α (FOLR1). Here, we first show that miR-34a, a TP53 transcriptional target, is reduced in PCa that harbors TP53 loss or mutations and that miR-34a mimic, when transfected into PCa cells, downregulated multiple miR-34a targets and inhibited cell growth. When exploring the therapeutic potential of folate-miR-34a, we found that folate-miR-34a exhibited impressive inhibitory effects on breast, ovarian and cervical cancer cells but showed minimal effects on and targeted delivery to PCa cells due to a lack of appreciable expression of FOLR1 in PCa cells. Folate-miR-34a also did not display any apparent effect on PCa cells expressing prostate-specific membrane antigen (PMSA) despite the reported folate's binding capability to PSMA. These results highlight challenges in specific delivery of folate-miR-34a to PCa due to lack of target (receptor) expression. Our study offers novel insights on the challenges and promises within the field and cast light on the development of ligand-conjugated miR-34a therapeutics for PCa.

Non-coding RNAs as potential therapeutic targets for receptor tyrosine kinase signaling in solid tumors: current status and future directions

This review article presents an in-depth analysis of the current state of research on receptor tyrosine kinase regulatory non-coding RNAs (RTK-RNAs) in solid tumors. RTK-RNAs belong to a class of non-coding RNAs (nc-RNAs) responsible for regulating the expression and activity of receptor tyrosine kinases (RTKs), which play a critical role in cancer development and progression. The article explores the molecular mechanisms through which RTK-RNAs modulate RTK signaling pathways and highlights recent advancements in the field. This include the identification of potential new RTK-RNAs and development of therapeutic strategies targeting RTK-RNAs. While the review discusses promising results from a variety of studies, encompassing in vitro, in vivo, and clinical investigations, it is important to acknowledge the challenges and limitations associated with targeting RTK-RNAs for therapeutic applications. Further studies involving various cancer cell lines, animal models, and ultimately, patients are necessary to validate the efficacy of targeting RTK-RNAs. The specificity of ncRNAs in targeting cellular pathways grants them tremendous potential, but careful consideration is required to minimize off-target effects, the article additionally discusses the potential clinical applications of RTK-RNAs as biomarkers for cancer diagnosis, prognosis, and treatment. In essence, by providing a comprehensive overview of the current understanding of RTK-RNAs in solid tumors, this review emphasizes their potential as therapeutic targets for cancer while acknowledging the associated challenges and limitations.

Downregulation of microRNA-326 enhances ZNF322A expression, transcriptional activity and tumorigenic effects in lung cancer

Zinc finger protein ZNF322A is an oncogenic transcription factor. Overexpression of ZNF322A activates pro-metastasis, cancer stemness, and neo-angiogenesis-related genes to enhance lung cancer progression. However, the upstream regulator of ZNF322A is not well defined. Dysregulation of microRNAs (miRNAs) can mediate cancer cell growth, migration, and invasion to promote tumorigenesis. Here, we uncover the mechanism of miRNA-mediated transcriptional regulation in ZNF322A-driven oncogenic events. ZNF322A harbors several putative miRNA-binding sites in the 3'-untranslated region (UTR). We validated that miR-326 downregulated ZNF322A-3'-UTR luciferase activity and mRNA expression. Furthermore, miR-326 suppressed the expression of ZNF322A-driven cancer-associated genes such as cyclin D1 and alpha-adducin. Reconstitution experiments by ectopic overexpression of ZNF322A abolished miR-326-suppressed cancer cell proliferation and cell migration capacity. Moreover, miR-326 attenuated ZNF322A-induced tumor growth and lung tumor metastasis in vivo. Clinically, the expression of miR-326 negatively correlated with ZNF322A mRNA expression in surgically resected tissues from 120 non-small cell lung cancer (NSCLC) patients. Multivariate Cox regression analysis demonstrated that NSCLC patients with low miR-326/high ZNF322A profile showed poor overall survival. Our results reveal that the deregulated expression of miR-326 leads to hyperactivation of ZNF322A-driven oncogenic signaling. Targeting the miR-326/ZNF322A axis would provide new therapeutic strategies for lung cancer patients.

Plasma Levels of mir-34a-5p Correlate with Systemic Inflammation and Low Naïve CD4 T Cells in Common Variable Immunodeficiency

PURPOSE

Common variable immunodeficiency (CVID) is a primary antibody deficiency that commonly manifests as recurrent infections. Many CVID patients also suffer from immune dysregulation, an inflammatory condition characterized by polyclonal lymphocytic tissue infiltration and associated with increased morbidity and mortality. The genetic cause is unknown in most CVID patients and epigenetic alterations may contribute to the broad range of clinical manifestations. MicroRNAs are small non-coding RNAs that are involved in epigenetic modulation and may contribute to the clinical phenotype in CVID.

METHODS

Here, we determined the circulating microRNAome and plasma inflammatory proteins of a cohort of CVID patients with various levels of immune dysregulation and compared them to healthy controls. A set of deregulated microRNAs was validated by qPCR and correlated to inflammatory proteins and clinical findings.

RESULTS

Levels of microRNA-34a correlated with 11 proteins such as CXCL9, TNF, and IL10, which were predicted to be biologically connected. Moreover, there was a negative correlation between mir-34 levels and the number of naïve CD4 T cells in CVID.

CONCLUSION

Collectively, our data show that microRNAs correlate with the inflammatory response in CVID. Further investigations are needed to elucidate the role of miRNAs in the development of CVID-related immune dysregulation.

Comparative Insight into Microglia/Macrophages-Associated Pathways in Glioblastoma and Alzheimer's Disease

Microglia and macrophages are pivotal to the brain's innate immune response and have garnered considerable attention in the context of glioblastoma (GBM) and Alzheimer's disease (AD) research. This review delineates the complex roles of these cells within the neuropathological landscape, focusing on a range of signaling pathways-namely, NF-κB, microRNAs (miRNAs), and TREM2-that regulate the behavior of tumor-associated macrophages (TAMs) in GBM and disease-associated microglia (DAMs) in AD. These pathways are critical to the processes of neuroinflammation, angiogenesis, and apoptosis, which are hallmarks of GBM and AD. We concentrate on the multifaceted regulation of TAMs by NF-κB signaling in GBM, the influence of TREM2 on DAMs' responses to amyloid-beta deposition, and the modulation of both TAMs and DAMs by GBM- and AD-related miRNAs. Incorporating recent advancements in molecular biology, immunology, and AI techniques, through a detailed exploration of these molecular mechanisms, we aim to shed light on their distinct and overlapping regulatory functions in GBM and AD. The review culminates with a discussion on how insights into NF-κB, miRNAs, and TREM2 signaling may inform novel therapeutic approaches targeting microglia and macrophages in these neurodegenerative and neoplastic conditions. This comparative analysis underscores the potential for new, targeted treatments, offering a roadmap for future research aimed at mitigating the progression of these complex diseases.

Functional and Potential Therapeutic Implication of MicroRNAs in Pancreatic Cancer

The alarmingly low five-year survival rate for pancreatic cancer presents a global health challenge, contributing to about 7% of all cancer-related deaths. Late-stage diagnosis and high heterogeneity are the biggest hurdles in treating pancreatic cancer. Thus, there is a pressing need to discover novel biomarkers that could help in early detection as well as improve therapeutic strategies. MicroRNAs (miRNAs), a class of short non-coding RNA, have emerged as promising candidates with regard to both diagnostics and therapeutics. Dysregulated miRNAs play pivotal roles in accelerating tumor growth and metastasis, orchestrating tumor microenvironment, and conferring chemoresistance in pancreatic cancer. The differential expression profiles of miRNAs in pancreatic cancer could be utilized to explore novel therapeutic strategies. In this review, we also covered studies on recent advancements in various miRNA-based therapeutics such as restoring miRNAs with a tumor-suppressive function, suppressing miRNA with an oncogenic function, and combination with chemotherapeutic drugs. Despite several challenges in terms of specificity and targeted delivery, miRNA-based therapies hold the potential to revolutionize the treatment of pancreatic cancer by simultaneously targeting multiple signaling pathways.

Expanding Roles of the E2F-RB-p53 Pathway in Tumor Suppression

The transcription factor E2F links the RB pathway to the p53 pathway upon loss of function of pRB, thereby playing a pivotal role in the suppression of tumorigenesis. E2F fulfills a major role in cell proliferation by controlling a variety of growth-associated genes. The activity of E2F is controlled by the tumor suppressor pRB, which binds to E2F and actively suppresses target gene expression, thereby restraining cell proliferation. Signaling pathways originating from growth stimulative and growth suppressive signals converge on pRB (the RB pathway) to regulate E2F activity. In most cancers, the function of pRB is compromised by oncogenic mutations, and E2F activity is enhanced, thereby facilitating cell proliferation to promote tumorigenesis. Upon such events, E2F activates the Arf tumor suppressor gene, leading to activation of the tumor suppressor p53 to protect cells from tumorigenesis. ARF inactivates MDM2, which facilitates degradation of p53 through proteasome by ubiquitination (the p53 pathway). P53 suppresses tumorigenesis by inducing cellular senescence or apoptosis. Hence, in almost all cancers, the p53 pathway is also disabled. Here we will introduce the canonical functions of the RB-E2F-p53 pathway first and then the non-classical functions of each component, which may be relevant to cancer biology.

The role of microRNAs in hepatocellular carcinoma: Therapeutic targeting of tumor suppressor and oncogenic genes

Hepatocellular carcinoma (HCC) is a severe malignant liver cancer with a poor prognosis and a high mortality rate. This carcinoma is a multistage process that begins with chronic hepatitis and progresses to cirrhosis, dysplastic nodules, and eventually HCC. However, the exact molecular etiology remains unclear. MicroRNAs (miRs) are small non-coding RNAs that modulate the expression of numerous genes. These molecules have become significant participants in several functions, including cell proliferation, differentiation, development, and tumorrelated properties. They have a pivotal role in carcinogenesis as oncogenes or tumor suppressor genes. Furthermore, some investigations have shown that particular miRs might be used as predictive or diagnostic markers and therapeutic targets in HCC therapy. This review study summarizes the current level of knowledge on the role of miRs in the initiation and progression of HCC.

A concise review on miRNAs as regulators of colon cancer stem cells and associated signalling pathways

Despite recent therapy advances and a better understanding of colon cancer biology, it remains one of the major causes of death. The cancer stem cells, associated with the progression, metastasis, and recurrence of colon cancer, play a major role in promoting the development of tumour and are found to be chemo resistant. The stroma of the tumour, which makes up the bulk of the tumour mass, is composed of the tumour microenvironment. With the advent of theranostic and the development of personalised medicine, miRNAs are becoming increasingly important in the context of colon malignancies. A holistic understanding of the regulatory roles of miRNAs in cancer cells and cancer stem cells will allow us to design effective strategies to regulate miRNAs, which could lead to improved clinical translation and creating a potent colon cancer treatment strategy. In this review paper, we briefly discuss the history of miRNA as well as the mechanisms of miRNA and cancer stem cells that contribute to the tumour growth, apoptosis, and advancement of colon cancer. The usefulness of miRNA in colorectal cancer theranostic is further concisely reviewed. We conclude by holding a stance in addressing the prospects and possibilities for miRNA by the disclosure of recent theranostic approaches aimed at eradicating cancer stem cells and enhancing overall cancer treatment outcomes.

Engineering HEK293T cell line by lentivirus to produce miR34a-loaded exosomes

BACKGROUND

RNA (ribonucleic acid) antisense is developing as a possible treatment option. As an RNA, miR-34a is involved in P53 function and cancer cell apoptosis. Although the therapeutic applications of miRNAs have several limitations, such as structural instability and susceptibility to nucleases. To resolve these issues, this study aims to apply exosomes as a delivery vehicle for miR-34a.

AIMS

This study aims to create a cell factory to generate miR34a-enriched exosomes. The produced nanoparticles act as a delivery system and improve the structural stability of miR34a.

METHODS

First exosome specific sequences were inserted into miR34a. The resulting miR34a oligonucleotide was transduced HEK293T cells genome with a lentiviral system. In the structure of miR34a oligonucleotide, six nucleotides were substituted to increase its packaging rate into exosomes. To maintain the secondary structure, stability, and expression of the miRNA gene, changes to the miR34a oligonucleotide were made using PCR (polymerase chain reaction) Extension. The forward-34a (5-TGGGGAGAGGCAGGACAGG-3) and Reverse-34a primers (5-TCCGAAGTCCTGGCGTCTCC-3) were used for amplification of the miR34a gene from DNA.

RESULTS

The results confirmed that the changes in miR34a oligonucleotide do not affect its secondary structure. The energy level of the manipulated miR34a oligonucleotide was kept the same compared to the original one. Moreover, the loading of miR34a to the exosomes was increased.

CONCLUSION

Our findings revealed that normal HEK293T did not express miR34a. However, lentiviral transduced miR34a oligonucleotide induced the loading of miR34a into the exosome. Moreover, replacing six nucleic acids in the 3' end of miR34a increased the loading of miR34a to exosome.

Role of microRNA-34a in blood-brain barrier permeability and mitochondrial function in ischemic stroke

Over the past decade, there has been an uptick in the number of studies conducting research on the role of microRNA (miRNA) molecules in stroke. Among these molecules, miR-34a has emerged as a significant player, as its levels have been observed to exhibit a substantial rise following ischemic events. Elevated levels of miR-34a have been found to have multiple effects, including the modulation of inflammatory molecules involved in the post-stroke recovery process, as well as negative effects on the blood-brain barrier (BBB) permeability. Interestingly, the increase of miR-34a appears to increase BBB permeability post stroke, through the negative effect on mitochondrial function. The strength of mitochondrial function is crucial for limiting para-cellular permeability and maintaining the structural integrity of the BBB. Furthermore, the activation of ischemic repair mechanisms and the reduction of ischemic event damage depend on healthy mitochondrial activity. This review aims to emphasize the involvement of miR-34a in ischemic stroke, specifically its interaction with mitochondrial genes in cerebrovascular endothelial cells, the effect on mitochondrial function, and lastly its regulatory role in BBB permeability. A comprehensive understanding of the role of miR-34a in maintaining BBB integrity and its contribution to the pathogenesis of stroke holds significant value in establishing a foundation for the development of future therapeutics and diagnostic markers.

Interplay of Extracellular Vesicles and TLR4 Signaling in Hepatocellular Carcinoma Pathophysiology and Therapeutics

Hepatocellular carcinoma (HCC) stands as a significant contributor to global cancer-related mortality. Chronic inflammation, often arising from diverse sources such as viral hepatitis, alcohol misuse, nonalcoholic fatty liver disease (NAFLD), and nonalcoholic steatohepatitis (NASH), profoundly influences HCC development. Within this context, the interplay of extracellular vesicles (EVs) gains prominence. EVs, encompassing exosomes and microvesicles, mediate cell-to-cell communication and cargo transfer, impacting various biological processes, including inflammation and cancer progression. Toll-like receptor 4 (TLR4), a key sentinel of the innate immune system, recognizes both pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs), thereby triggering diverse signaling cascades and pro-inflammatory cytokine release. The intricate involvement of the TLR4 signaling pathway in chronic liver disease and HCC pathogenesis is discussed in this study. Moreover, we delve into the therapeutic potential of modulating the TLR4 pathway using EVs as novel therapeutic agents for HCC. This review underscores the multifaceted role of EVs in the context of HCC and proposes innovative avenues for targeted interventions against this formidable disease.

TP53 gene implications in prostate cancer evolution: potential role in tumor classification

Background and aims

Prostate adenocarcinoma (PRAD) is a complex disease that can be driven by alterations in both coding and noncoding genes. Recent research has identified coding and non-coding genes that are considered to play important roles in prostate cancer evolution and which may be used as biomarkers for disease diagnosis, prognosis, and treatment. TP53 is a critical hub gene in prostate cancer. Advanced studies have demonstrated the crosstalk between coding and non-coding RNAs, particularly microRNAs (miRNAs).

Methods

In this study, we investigated the roundabout of TP53 and their regulatory miRNAs (miR-15a-5p, miR-34a-5p, and miR-141-3p) based on the TCGA data set. We validated an additional patient cohort of 28 matched samples of patients with PRAD at tissue and plasma level.

Results

Therefore, using the UALCAN online database, we evaluated the expression level in PRAD of these genes revealing overexpression of TP53. qRT-PCR validation step endorsed the expression level for these genes. Additionally, we evaluated the expression level of the four key miRNAs (miR-15a-5p, miR-34a-5p, and miR-141-3p) interconnected as a network at tissue and plasma levels.

Conclusions

Through these results, we demonstrated the essential function of TP53 and its associated miRNAs that play a significant role in tumor control, highlighting miRNAs' potential as future therapeutic targets and biomarkers with important implications in managing prostate cancer.

Deciphering the Mysterious Relationship between the Cross-Pathogenetic Mechanisms of Neurodegenerative and Oncological Diseases

The relationship between oncological pathologies and neurodegenerative disorders is extremely complex and is a topic of concern among a growing number of researchers around the world. In recent years, convincing scientific evidence has accumulated that indicates the contribution of a number of etiological factors and pathophysiological processes to the pathogenesis of these two fundamentally different diseases, thus demonstrating an intriguing relationship between oncology and neurodegeneration. In this review, we establish the general links between three intersecting aspects of oncological pathologies and neurodegenerative disorders, i.e., oxidative stress, epigenetic dysregulation, and metabolic dysfunction, examining each process in detail to establish an unusual epidemiological relationship. We also focus on reviewing the current trends in the research and the clinical application of the most promising chemical structures and therapeutic platforms that have a modulating effect on the above processes. Thus, our comprehensive analysis of the set of molecular determinants that have obvious cross-functional pathways in the pathogenesis of oncological and neurodegenerative diseases can help in the creation of advanced diagnostic tools and in the development of innovative pharmacological strategies.

MicroRNA-34 Family in Cancers: Role, Mechanism, and Therapeutic Potential

MicroRNA (miRNA) are small noncoding RNAs that play vital roles in post-transcriptional gene regulation by inhibiting mRNA translation or promoting mRNA degradation. The dysregulation of miRNA has been implicated in numerous human diseases, including cancers. miR-34 family members (miR-34s), including miR-34a, miR-34b, and miR-34c, have emerged as the most extensively studied tumor-suppressive miRNAs. In this comprehensive review, we aim to provide an overview of the major signaling pathways and gene networks regulated by miR-34s in various cancers and highlight the critical tumor suppressor role of miR-34s. Furthermore, we will discuss the potential of using miR-34 mimics as a novel therapeutic approach against cancer, while also addressing the challenges associated with their development and delivery. It is anticipated that gaining a deeper understanding of the functions and mechanisms of miR-34s in cancer will greatly contribute to the development of effective miR-34-based cancer therapeutics.

DNA methylome analysis reveals potential alterations contributing to the progression of bronchial hyperplasia

BACKGROUND

Squamous cell lung cancer (SCLC) arises from bronchial changes: basal cell hyperplasia (BCH), squamous metaplasia (SM), and dysplasia. However, the premalignant process preceding SCLC is not inevitable; it can stop at any of the bronchial lesions. Previously, we hypothesized that combinations of premalignant lesions observed in the small bronchi of SCLC patients can reflect the different "scenarios" of the premalignant process: BCHi-the stoppage at the stage of hyperplasia and BCHSM-the progression of hyperplasia to metaplasia.

METHODS AND RESULTS

In this study, using whole-genome bisulfite sequencing we analyzed the DNA methylome of two forms of BCH: isolated BCH (BCHi) and BCH co-occurred with SM (BCHSM) in the small bronchi of SCLC patients. It was shown that BCHi harbored differentially methylated regions (DMRs) affecting genes associated with regulating phosphatase activity. In BCHSM, DMRs were found in genes involved in PI3K-Akt and AMPK signaling pathways. DMRs were also found to affect specific miRNA genes: miR-34a and miR-3648 in BCHi and miR-924 and miR-100 in BCHSM.

CONCLUSIONS

Thus, this study demonstrated the significant changes in DNA methylome between the isolated BCH and BCH combined with SM. The identified epigenetic alterations may underlie different "scenarios" of the premalignant process in the bronchial epithelium.

The Mechanism of Anti-Tumor Activity of 6-Morpholino- and 6-Amino-9-Sulfonylpurine Derivatives on Human Leukemia Cells

The aim of this study was to explore the mechanism of antitumor effect of (E)-6-morpholino-9-(styrylsulfonyl)-9H-purine (6-Morpholino-SPD) and (E)-6-amino-9-(styrylsulfonyl)-9H-purine (6-Amino-SPD). The effects on apoptosis induction, mitochondrial potential, and accumulation of ROS in treated K562 cells were determined by flow cytometry. The RT-PCR method was used to measure the expression of Akt, CA IX, caspase 3, and cytochrome c genes, as well as selected miRNAs. Western blot analysis was used to determine the expression of Akt, cytochrome c, and caspase 3. The results demonstrate the potential of the tested derivatives as effective antitumor agents with apoptotic-inducing properties. In leukemic cells treated with 6-Amino-SPD, increased expression of caspase 3 and cytochrome c genes was observed, indicating involvement of the intrinsic mitochondrial pathway in the induction of apoptosis. Conversely, leukemic cells treated with 6-Morpholino-SPD showed reduced expression of these genes. The observed downregulation of miR-21 by 6-Morpholino-SPD may contribute to the induction of apoptosis and disruption of mitochondrial function. In addition, both derivatives exhibited increased expression of Akt and CA IX genes, suggesting activation of the Akt/HIF pathway. However, the exact mechanism and its relations to the observed overexpression of miR-210 need further investigation. The acceptable absorption and distribution properties predicted by ADMET analysis suggest favorable pharmacokinetic properties for these derivatives.

p53 isoform expression promotes a stemness phenotype and inhibits doxorubicin sensitivity in breast cancer

In breast cancer, dysregulated TP53 expression signatures are a better predictor of chemotherapy response and survival outcomes than TP53 mutations. Our previous studies have shown that high levels of Δ40p53 are associated with worse disease-free survival and disruption of p53-induced DNA damage response in breast cancers. Here, we further investigated the in vitro and in vivo implications of Δ40p53 expression in breast cancer. We have shown that genes associated with cell differentiation are downregulated while those associated with stem cell regulation are upregulated in invasive ductal carcinomas expressing high levels of Δ40p53. In contrast to p53, endogenous ∆40p53 co-localised with the stem cell markers Sox2, Oct4, and Nanog in MCF-7 and ZR75-1 cell lines. ∆40p53 and Sox2 co-localisation was also detected in breast cancer specimens. Further, in cells expressing a high ∆40p53:p53 ratio, increased expression of stem cell markers, greater mammosphere and colony formation capacities, and downregulation of miR-145 and miR-200 (p53-target microRNAs that repress stemness) were observed compared to the control subline. In vivo, a high ∆40p53:p53 ratio led to increased tumour growth, Ki67 and Sox2 expression, and blood microvessel areas in the vehicle-treated mice. High expression of ∆40p53 also reduced tumour sensitivity to doxorubicin compared to control tumours. Enhanced therapeutic efficacy of doxorubicin was observed when transiently targeting Δ40p53 or when treating cells with OTSSP167 with concomitant chemotherapy. Taken together, high Δ40p53 levels induce tumour growth and may promote chemoresistance by inducing a stemness phenotype in breast cancer; thus, targeting Δ40p53 in tumours that have a high Δ40p53:p53 ratio could enhance the efficacy of standard-of-care therapies such as doxorubicin.

Distinct oncogenic phenotypes in hematopoietic specific deletions of Trp53

Loss of function in the tumor suppressor gene TP53 is the most common alteration seen in human cancer. In mice, P53 deletion in all cells leads predominantly to the development of T-cell lymphomas, followed by B-cell lymphomas, sarcomas and teratomas. In order to dissect the role of P53 in the hematopoietic system, we generated and analyzed two different mouse models deficient for P53. A pan-hematopoietic P53 deletion mouse was created using Vav1-Cre based deletion; and a B-cell-specific deletion mouse was created using a CD19-Cre based deletion. The Vav1-P53CKO mice predominantly developed T-cell malignancies in younger mice, and myeloid malignancies in older mice. In T-cell malignancies, there was accelerated thymic cell maturation with overexpression of Notch1 and its downstream effectors. CD19-P53CKO mice developed marginal zone expansion in the spleen, followed by marginal zone lymphoma, some of which progressed to diffuse large B-cell lymphomas. Interestingly, marginal zone and diffuse large B-cell lymphomas had a unique gene expression signature characterized by activation of the PI3K pathway, compared with wild type marginal zone or follicular cells of the spleen. This study demonstrates lineage specific P53 deletion leading to distinct phenotypes secondary to unique gene expression programs set in motion.

Targeted therapy using nanocomposite delivery systems in cancer treatment: highlighting miR34a regulation for clinical applications

The clinical application of microRNAs in modern therapeutics holds great promise to uncover molecular limitations and conquer the unbeatable castle of cancer metastasis. miRNAs play a decisive role that regulating gene expression at the post-transcription level while controlling both the stability and translation capacity of mRNAs. Specifically, miR34a is a master regulator of the tumor suppressor gene, cancer progression, stemness, and drug resistance at the cell level in p53-dependent and independent signaling. With changing, trends in nanotechnology, in particular with the revolution in the field of nanomedicine, nano drug delivery systems have emerged as a prominent strategy in clinical practices coupled with miR34a delivery. Recently, it has been observed that forced miR34a expression in human cancer cell lines and model organisms limits cell proliferation and metastasis by targeting several signaling cascades, with various studies endorsing that miR34a deregulation in cancer cells modulates apoptosis and thus requires targeted nano-delivery systems for cancer treatment. In this sense, the present review aims to provide an overview of the clinical applications of miR34a regulation in targeted therapy of cancer.

P53/miR-34a/SIRT1 positive feedback loop regulates the termination of liver regeneration

BACKGROUND

The capacity of the liver to restore its architecture and function assures good prognoses of patients who suffer serious hepatic injury, cancer resection, or living donor liver transplantation. Only a few studies have shed light on the mechanisms involved in the termination stage of LR. Here, we attempt to further verify the role of the p53/miR-34a/SIRT1 positive feedback loop in the termination of liver regeneration and its possible relationship with liver cancer.

METHOD

We performed partial hepatectomy (PH) in mice transfected with adenovirus (Ade) overexpressing P53 and adenovirus-associated virus (AAV) overexpressing miR-34a. LR was analyzed by liver weight/body weight, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels and cell proliferation, and the related cellular signals were investigated. Bile acid (BA) levels during LR were analyzed by metabolomics of bile acids.

RESULTS

We found that the P53/miR-34a/SIRT1 positive feedback loop was activated in the late phase of LR. Overexpression of P53 or miR-34a terminated LR early and enhanced P53/miR-34a/SIRT1 positive feedback loop expression and its proapoptotic effect. T-β-MCA increased gradually during LR and peaked at 7 days after PH. T-β-MCA inhibited cell proliferation and promoted cell apoptosis via facilitating the P53/miR-34a/SIRT1 positive feedback loop during LR by suppressing FXR/SHP. The P53/miR-34a/SIRT1 positive feedback loop was abolished in HCC patients with P53 mutations.

CONCLUSIONS

The P53/miR-34a/SIRT1 positive feedback loop plays an important role in the termination of LR. Our findings showed the molecular and metabolic mechanisms of LR termination and provide a potential therapeutic alternative for treating P53-wild-type HCC patients.

Research progress on non-protein-targeted drugs for cancer therapy

Non-protein target drugs, especially RNA-based gene therapies for treating hereditary diseases, have been recognized worldwide. As cancer is an insurmountable challenge, no miracle drug is currently available. With the advancements in the field of biopharmaceuticals, research on cancer therapy has gradually focused on non-protein target-targeted drugs, especially RNA therapeutics, including oligonucleotide drugs and mRNA vaccines. This review mainly summarizes the clinical research progress in RNA therapeutics and highlights that appropriate target selection and optimized delivery vehicles are key factors in increasing the effectiveness of cancer treatment in vivo.

The Role of miRNA-221 and miRNA-34a in Non-Melanoma Skin Cancer of the Head and Neck Region

Non-melanoma skin cancer (NMSC) is one of the most frequent types of malignancy in the human body with an increasing incidence. Short, non-coding RNA molecules called microRNAs (miRNAs) can control post-transcriptional gene expression and they have a significant role in several physiological cellular processes and pathologies, including cancer. Depending on the functions of the genes, miRNAs may function as oncogenes or tumor suppressors. The aim of this paper was to describe the role of miRNA-34a and miRNA-221 in head and neck NMSC. Thirty-eight NMSC match paired (tumor and adjacent) tissue samples were evaluated by qRT-PCR. Total RNA was extracted and isolated from tissue samples using the phenol-chloroform (Trireagent) method according to the manufacturer's protocol. The concentration of RNA was measured by a NanoDrop-1000 spectrophotometer. The expression level of each miRNA was calculated by threshold cycle. For all statistical tests, the 0.05 significance level was used and two-tailed p values. All analyses were conducted in an R environment for statistical computing and graphics. We found the miRNA-221 being overexpressed in squamous cell carcinoma (SCC) (p < 0.05), basal cell carcinoma (BCC) and basosquamous cell carcinoma (BSC) compared with adjacent normal tissue. Additionally, the levels of miRNA-221 were two times higher (p < 0.05) in cases where the excision of the tumor was done with positive margins (R1), which means that we are the first to highlight the potential role of miRNA-221 in the microscopical local invasion. Mi-RNA-34a expression was altered in the malignant tissue compared with the adjacent normal one both in BCC and SCC but not statistically significantly. In conclusion, NMSC are challenging because of their increasing incidence and rapidly evolving development and discovering their molecular mechanisms of action lead us to understand tumorigenesis and evolution, while also contributing to the implementation of novel therapeutic keys.

microRNAs (miRNAs) in Glioblastoma Multiforme (GBM)-Recent Literature Review

Glioblastoma multiforme (GBM) is the most common, malignant, poorly promising primary brain tumor. GBM is characterized by an infiltrating growth nature, abundant vascularization, and a rapid and aggressive clinical course. For many years, the standard treatment of gliomas has invariably been surgical treatment supported by radio- and chemotherapy. Due to the location and significant resistance of gliomas to conventional therapies, the prognosis of glioblastoma patients is very poor and the cure rate is low. The search for new therapy targets and effective therapeutic tools for cancer treatment is a current challenge for medicine and science. microRNAs (miRNAs) play a key role in many cellular processes, such as growth, differentiation, cell division, apoptosis, and cell signaling. Their discovery was a breakthrough in the diagnosis and prognosis of many diseases. Understanding the structure of miRNAs may contribute to the understanding of the mechanisms of cellular regulation dependent on miRNA and the pathogenesis of diseases underlying these short non-coding RNAs, including glial brain tumors. This paper provides a detailed review of the latest reports on the relationship between changes in the expression of individual microRNAs and the formation and development of gliomas. The use of miRNAs in the treatment of this cancer is also discussed.

Zip Nucleic Acid-Based Genomagnetic Assay for Electrochemical Detection of microRNA-34a

Zip nucleic acid (ZNA)-based genomagnetic assay was developed herein for the electrochemical detection of microRNA-34a (miR-34a), which is related to neurological disorders and cancer. The hybridization between the ZNA probe and miR-34a target was performed in the solution phase; then, the resultant hybrids were immobilized onto the surface of magnetic beads (MBs). After magnetic separation, the hybrids were separated from the surface of MBs and then immobilized on the surface of pencil graphite electrodes (PGEs). In the case of a full-match hybridization, the guanine oxidation signal was measured via the differential pulse voltammetry (DPV) technique. All the experimental parameters that influenced the hybridization efficiency (i.e., hybridization strategy, probe concentration, hybridization temperature, etc.) were optimized. The cross-selectivity of the genomagnetic assay was tested against two different miRNAs, miR-155 and miR-181b, individually as well as in mixture samples. To show the applicability of the ZNA-based genomagnetic assay for miR-34a detection in real samples, a batch of experiments was carried out in this study by using the total RNA samples isolated from the human hepatocellular carcinoma cell line (HUH-7).

Gentamycin Rationally Repositioned to Inhibit miR-34a Ameliorates Oxidative Injury to PC12 Cells

Ischemic stroke accompanies oxidative stress and cell death in the cerebral tissue. The microRNA miR-34a plays a pivotal role in this molecular pathology. This study presents the rational repositioning of aminoglycosidic antibiotics as miR-34a antagonists in order to assess their efficiency in protecting the PC12 stroke model cells from oxidative stress occurring under cerebral ischemic conditions. A library of 29 amino-sugar compounds were screened against anticipated structural models of miR-34a through molecular docking. MiR-ligand interactions were mechanistically studied by molecular dynamics simulations and free-energy calculations. Cultured PC12 cells were treated by H₂O₂ alone or in combination with gentamycin and neomycin as selected drugs. Cell viability and apoptosis were detected by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) and annexin V-FITC/propidium iodate (PI) double staining assays, respectively. The expression levels of key factors involved in cell proliferation, oxidative stress, and apoptosis in treated PC12 cells were measured through a quantitative real-time polymerase chain reaction and flow cytometric annexin V-FITC/PI double staining assays. A stable and energetically favorable binding was observed for miR-34a with gentamycin and neomycin. Gentamycin pretreatments followed by H₂O₂ oxidative injury led to increased cell viability and protected PC12 cells against H₂O₂-induced apoptotic events. This study will help in further understanding how the suppression of miR-34a in neural tissue affects the cell viability upon stroke.

LINC01711 promotes transforming growth factor-beta (TGF-β) induced invasion in glioblastoma multiforme (GBM) by acting as a competing endogenous RNA for miR-34a and promoting ZEB1 expression

GBM is the central nervous system's most aggressive and malignant tumor. TGF-β expression is elevated in GBM, and it promotes invasion and EMT. TGF-β regulates the expression of several lncRNAs, which promote glioma pathogenesis. Here we characterize the role of TGF-β-induced lncRNA- LINC01711 in glioma pathogenesis. We show that LINC01711 expression is significantly upregulated in GBM tissues and is associated with poor overall survival of GBM patients. Loss-of-function studies illustrate that LINC01711 promotes proliferation, migration, and invasion in GBM. In addition, LINC01711 depletion sensitizes glioma cells to Temozolomide (TMZ) induced apoptosis by inhibiting ZEB1 expression. LINC01711 functions as a competing endogenous RNA for miR-34a and promotes ZEB1 expression to regulate invasion. Our findings suggest that LINC01711 is an attractive therapeutic target for GBM.

Role of noncoding RNAs in cardiac ageing

The global population is estimated to reach 9.8 billion by 2050, of which 2.1 billion will comprise individuals above 60 years of age. As the number of elderly is estimated to double from 2017, it is a victory of the modern healthcare system but also worrisome as ageing, and the onset of chronic disease are correlated. Among other chronic conditions, cardiovascular diseases (CVDs) are the leading cause of death in the aged population. While the underlying cause of the age-associated development of CVDs is not fully understood, studies indicate the role of non-coding RNAs such as microRNAs (miRNAs) and long noncoding RNAs (lnc-RNAs) in the development of age-associated CVDs. miRNAs and lnc-RNAs are non-coding RNAs which control gene expression at the post-transcriptional level. The expression of specific miRNAs and lnc-RNAs are reportedly dysregulated with age, leading to cardiovascular system changes and ultimately causing CVDs. Since miRNAs and lnc-RNAs play several vital roles in maintaining the normal functioning of the cardiovascular system, they are also being explored for their therapeutic potential as a treatment for CVDs. This review will first explore the pathophysiological changes associated with ageing. Next, we will review the known mechanisms underlying the development of CVD in ageing with a specific focus on miRNA and lnc-RNAs. Finally, we will discuss the therapeutic options and future challenges towards healthy cardiac ageing. With the global ageing population on the rise, this review will provide a fundamental understanding of some of the underlying molecular mechanisms of cardiac ageing.

Therapeutic potential of targeting mirnas to prostate cancer tumors: using psma as an active target

Prostate cancer (PC) is a commonly diagnosed malignancy in men and is associated with high mortality rates. Current treatments for PC include surgery, chemotherapy, and radiation therapy. However, recent advances in targeted delivery systems have yielded promising new approaches to PC treatment. As PC epithelial cells express high levels of prostate-specific membrane antigen (PSMA) on the cell surface, new drug conjugates focused on PSMA targeting have been developed. microRNAs (miRNAs) are small noncoding RNAs that regulate posttranscriptional gene expression in cells and show excellent possibilities for use in developing new therapeutics for PC. PSMA-targeted therapies based on a miRNA payload and that selectively target PC cells enhances therapeutic efficacy without eliciting damage to normal surrounding tissue. This review discusses the rationale for utilizing miRNAs to target PSMA, revealing their potential in therapeutic approaches to PC treatment. Different delivery systems for miRNAs and challenges to miRNA therapy are also explored.

Serum miR-34a as a potential biomarker for diagnosis of inflammatory bowel diseases in Egyptian patients

Background

IBD is a multifactorial disease. Although dysbiosis of commensal bacteria and breakdown of the intestinal barrier are considered as major pathological mechanisms in the development of IBD, other important factors such as genetic aberrations also contribute to its development.

Results

Our results revealed that serum miR-34a RQ values were significantly lower and serum MACF1 RQ values were significantly higher in IBD patients compared to healthy controls. In addition, serum miR-34a in relation to pathological activity and disease severity in the IBD group revealed a significant difference (p>0.05).

Conclusion

Serum miR-34a RQ and serum MACF1 RQ value-based biomarker panels can act as a potential biomarker for IBD diagnosis and prognosis.

MicroRNAs in Cancer and Cardiovascular Disease

Although cardiac tumor formation is rare, accumulating evidence suggests that the two leading causes of deaths, cancers, and cardiovascular diseases are similar in terms of pathogenesis, including angiogenesis, immune responses, and fibrosis. These similarities have led to the creation of new exciting field of study called cardio-oncology. Here, we review the similarities between cancer and cardiovascular disease from the perspective of microRNAs (miRNAs). As miRNAs are well-known regulators of translation by binding to the 3'-untranslated regions (UTRs) of messenger RNAs (mRNAs), we carefully dissect how a specific set of miRNAs are both oncomiRs (miRNAs in cancer) and myomiRs (muscle-related miRNAs). Furthermore, from the standpoint of similar pathogenesis, miRNAs categories related to the similar pathogenesis are discussed; namely, angiomiRs, Immune-miRs, and fibromiRs.

TRIM47 promotes glioma angiogenesis by suppressing Smad4

Angiogenesis is required for tumor progression; thus, its investigation can be useful to identify strategies for potential cancer treatments. Tripartite motif 47 (TRIM47) is involved in the progression of multiple cancers. However, its role in glioma angiogenesis is largely unknown. In this study, we first showed that TRIM47 is frequently upregulated in gliomas, and increased TRIM47 levels are correlated with microvascular density. We then examined the role of TRIM47 in cellular functions related to angiogenesis in vitro and observed that TRIM47 knockdown significantly reduced human umbilical vein endothelial cell proliferation, migration, and tube formation. We also found that TRIM47 silencing reduced vessel density and tumor volume in glioma xenografts. Mechanistically, TRIM47 negatively regulated Smad4 expression in glioma cells, and SMAD4 knockdown rescued the suppressive effects of TRIM47 silencing. Taken together, our results indicate that TRIM47 promotes angiogenesis in gliomas by downregulating SMAD4. Therefore, targeting the TRIM47/SMAD4 axis may offer an innovative approach to glioma treatment.

Concise review: Cancer cell reprogramming and therapeutic implications

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The cancer stem cell (CSC) act as tumor initiating cells.

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Reprogramming technology can convert cells into CSCs.

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Metabolic reprogramming is critical for CSCs.

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MiRNA can mediate cancer cell reprogramming as emerging alternatives.

The cancer stem cell (CSC) hypothesis postulates that cancer originates from the malignant transformation of stem cells and is considered to apply to a variety of cancers. Additionally, cancer cells alter metabolic processes to sustain their characteristic uncontrolled growth and proliferation. Further, microRNAs (miRNAs) are found to be involved in acquisition of stem cell-like properties, regulation and reprogramming of cancer cells during cancer progression through its post-transcriptional-regulatory activity. In this concise review, we aim to integrate the current knowledge and recent advances to elucidate the mechanisms involved in the regulation of cell reprogramming and highlights the potential therapeutic implications for the future.

Plasma-Based microRNA Expression Analysis in Advanced Stage NSCLC Patients Treated with Nivolumab

Simple Summary

Nivolumab (anti-PD-1 inhibitor) is the first monoclonal antibody approved for the treatment of NSCLC, with research results showing that patients who had received previous lines of therapy had a better response to this treatment and better overall survival. Tissue-level analyses fail to capture the dynamic tumor-host relationship, in contrast to circulating biomarkers, which can reflect the systemic response of the tumor, allowing for repeated sampling and monitoring. In the context of liquid biopsy, microRNAs are studied as biomarkers of immunotherapy efficacy based on their role in regulating antitumor immunity. The present study suggests that miR-200c and miR-34a plasma expression levels have a prognostic role in patients with advanced NSCLC receiving Nivolumab. It further supports that the expression profile of circulating immunomodulatory microRNAs provides information on the survival of patients with advanced NSCLC receiving Nivolumab and could represent promising circulating biomarkers that may provide information about patients’ responses to immunotherapy.

Abstract

Since circulating microRNAs (miRNAs) are involved in the modulation of the immune response, they are tested as liquid biopsy-based biomarkers in patients with NSCLC treated with immunotherapy. We analyzed the expression levels and examined the clinical significance of immunoregulatory miRNAs involved in immune checkpoint regulation (miR-34a, miR-200b, miR-200c), T-cell activity (miR-155), and the function of myeloid-derived suppressive cells (MDSCs) (miR-223) or regulatory T lymphocytes (Tregs) (miR-146a), in patients with advanced NSCLC (N = 69) treated with anti-PD-1 (Nivolumab) immunotherapy as 2nd or 3rd line of treatment therapy. Plasma levels of circulating miRNAs were analyzed by RT-qPCR before the initiation of immunotherapy. Expression of miR-34a, miR-146a, mir-200c, and miR-223 was found to be associated with response to immunotherapy. High miR-200c expression emerged as an independent prognostic factor for inferior overall survival in all patients with NSCLC (OS, HR: 2.243, 95% CI: 1.208–4.163; p = 0.010) and in patients with non-Squamous (non-SqCC) subtype (N = 38) (HR: 2.809, 95% CI: 1.116–7.074; p = 0.028). Low miR-34a expression independently predicted for shorter OS (HR: 3.189, 95% CI: 1.193–8.527; p = 0.021) in the non-SqCC subgroup. Our findings suggest that alterations in circulating miR-200c and miR-34a expression levels are associated with the response and outcome in patients with advanced NSCLC treated with anti-PD1 immunotherapy.

MicroRNA-34a, Prostate Cancer Stem Cells, and Therapeutic Development

Prostate cancer (PCa) is a highly heterogeneous disease and typically presents with multiple distinct cancer foci. Heterogeneity in androgen receptor (AR) expression levels in PCa has been observed for decades, from untreated tumors to castration-resistant prostate cancer (CRPC) to disseminated metastases. Current standard-of-care therapies for metastatic CRPC can only extend life by a few months. Cancer stem cells (CSCs) are defined as a subpopulation of cancer cells that exists in almost all treatment-naive tumors. Additionally, non-CSCs may undergo cellular plasticity to be reprogrammed to prostate cancer stem cells (PCSCs) during spontaneous tumor progression or upon therapeutic treatments. Consequently, PCSCs may become the predominant population in treatment-resistant tumors, and the "root cause" for drug resistance. microRNA-34a (miR-34a) is a bona fide tumor-suppressive miRNA, and its expression is dysregulated in PCa. Importantly, miR-34a functions as a potent CSC suppressor by targeting many molecules essential for CSC survival and functions, which makes it a promising anti-PCSC therapeutic. Here, we conducted a comprehensive literature survey of miR-34a in the context of PCa and especially PCSCs. We provided an updated overview on the mechanisms of miR-34a regulation followed by discussing its tumor suppressive functions in PCa. Finally, based on current advances in miR-34a preclinical studies in PCa, we offered potential delivery strategies for miR-34a-based therapeutics for treating advanced PCa.

Involvement of microRNAs and their potential diagnostic, therapeutic, and prognostic role in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) accounts for 85%-90% of primary liver cancer. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression by targeting the 3'UTR of mRNA. Abnormal expression and regulation of miRNAs are involved in the occurrence and progression of HCC, and miRNAs can also play a role in the diagnosis and treatment of HCC as oncogenes or tumor suppressors.

METHODS

In the past decades, a large number of studies have shown that miRNAs play an essential regulatory role in HCC and have potential as biomarkers for HCC. We reviewed the literature to summarize these studies.

RESULTS

By reviewing the literature, we retrospected the roles of miRNAs in the development, diagnosis, treatment, and prognosis of HCC, and put forward prospects for the further research on miRNAs in the precision treatment of HCC.

CONCLUSION

MicroRNAs are important regulators and biomarkers in the occurrence, progression, outcome, and treatment of HCC, and can provide new targets and strategies for improving the therapeutic effect of HCC.

MicroRNA-204-5p: A pivotal tumor suppressor

MicroRNAs (miRNAs) are a class of non-coding single-stranded RNA molecules with a length of approximately 18-25 nt nucleotides that regulate gene expression post-transcriptionally. MiR-204-5p originates from the sixth intron of the transient receptor potential cation channel subfamily M member 3 (TRPM3) gene. MiR-204-5p is frequently downregulated in various cancer types and is related to the clinicopathological characteristics and prognosis of cancer patients. So far, many studies have determined that miR-204-5p functions as a tumor suppressor for its extensive and powerful capacity to inhibit tumor proliferation, metastasis, autophagy, and chemoresistance in multiple cancer types. MiR-204-5p appears to be a promising prognostic biomarker and a therapeutic target for human cancers. This review summarized the latest advances on the role of miR-204-5p in human cancers.