MicroRNA-378 is associated with non-small cell lung cancer brain metastasis by promoting cell migration, invasion and tumor angiogenesis

MiRNAs as new potential biomarkers and therapeutic targets in brain metastasis

Brain metastases represent a formidable challenge in cancer management, impacting a significant number of patients and contributing significantly to cancer-related mortality. Conventional diagnostic methods frequently fall short, underscoring the imperative for non-invasive alternatives. Non-coding RNAs (ncRNAs), specifically microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), present promising avenues for exploration. These ncRNAs exert influence over the prognosis and treatment resistance of brain metastases, offering valuable insights into underlying mechanisms and potential therapeutic targets. Dysregulated ncRNAs have been identified in brain metastases originating from various primary cancers, unveiling opportunities for intervention and prevention. The analysis of ncRNA expression in bodily fluids, such as serum and cerebrospinal fluid, provides a noninvasive means to differentiate brain metastases from primary tumors. NcRNAs, particularly miRNAs, assume a pivotal role in orchestrating the immune response within the brain microenvironment. MiRNAs exhibit promise in diagnosing brain metastases, effectively distinguishing between normal and cancer cells, and pinpointing the tissue of origin for metastatic brain tumors. The manipulation of miRNAs holds substantial potential in cancer treatment, offering the prospect of reducing toxicity and enhancing efficacy. Given the limited treatment options and the formidable threat of brain metastases in cancer patients, non-coding RNAs, especially miRNAs, emerge as beacons of hope, serving as both diagnostic tools and therapeutic targets. Further clinical studies are imperative to validate the specificity and sensitivity of ncRNAs, potentially reshaping approaches to tackle this challenge and elevate treatment outcomes for affected patients.

Serum miR-215-5p, miR-192-5p and miR-378a-5p as novel diagnostic biomarkers for periampullary adenocarcinoma

OBJECTIVE

MicroRNAs (miRNAs) are present in human serum in a stable form. Circulating miRNAs are increasingly recognized as promising biomarkers for early cancer detection. The aim of this study was to identify serum miRNAs as biomarkers for periampullary adenocarcinoma (PAC).

PATIENTS AND METHODS

68 patients with PAC and 50 healthy controls (HCs) subjects were recruited in this study. The expression levels of 11 selected miRNAs were determined in serum samples using the SYBR-green quantitative reverse transcription polymerase chain reaction (qRT-PCR) method. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic potential of serum miRNAs.

RESULTS

The expression levels of three miRNAs (miR-215-5p, miR-192-5p, and miR-378a-5p) were significantly upregulated in the serum samples derived from the PAC patients compared with those from the HC (p < 0.001). The ROC analysis showed that all three significantly altered miRNAs (miR-215-5p, miR-192-5p, and miR-378a-5p) could potentially discriminate patients with PAC from HC with AUC value of 0.771 (95% CI: 0.684-0.843), 0.877 (95% CI: 0.799-0.927) and 0.768 (95% CI: 0.674-0.853) respectively. Further comparisons showed that these three serum miRNAs (miR-215-5p, miR-192-5p, and miR-378a-5p) can strongly discriminate early-stage PAC patients from HC with an AUC value of 0.802 (95% CI: 0.719-0.886), 0.870 (95% CI: 0.793-0.974) and 0.793 (95% CI: 0.706-0.880) respectively, may aid in early detection of PAC.

CONCLUSIONS

Taken together, our findings demonstrated that these three serum miRNAs (miR-215-5p, miR-192-5p, and miR-378a-5p) may serve as noninvasive biomarkers for the early detection of PAC.

A Review of Recent Advances in the Molecular Mechanisms Underlying Brain Metastasis in Lung Cancer

Brain metastasis from lung cancer is a prevalent mode of treatment failure associated with a poor prognosis. The incidence of brain metastasis has recently shown a dramatic increase. The early detection and risk stratification of lung cancer-related brain metastasis would be highly advantageous for patients. However, our current knowledge and comprehension of the underlying mechanisms driving brain metastasis in lung cancer pose significant challenges. This review summarizes the mechanisms underlying brain metastasis, focusing on the intricate interplay between lung cancer-derived tumor cells and the unique characteristics of the brain, recent advancements in the identification of driver genes, concomitant genes, epigenetic features, including miRNAs and long noncoding RNAs, as well as the molecular characterization of brain metastasis originating from other organs, which may further enhance risk stratification and facilitate precise treatment strategies.

Exploring the Molecular Tumor Microenvironment and Translational Biomarkers in Brain Metastases of Non-Small-Cell Lung Cancer

Brain metastases represent a significant clinical challenge in the treatment of non-small-cell lung cancer (NSCLC), often leading to a severe decline in patient prognosis and survival. Recent advances in imaging and systemic treatments have increased the detection rates of brain metastases, yet clinical outcomes remain dismal due to the complexity of the metastatic tumor microenvironment (TME) and the lack of specific biomarkers for early detection and targeted therapy. The intricate interplay between NSCLC tumor cells and the surrounding TME in brain metastases is pivotal, influencing tumor progression, immune evasion, and response to therapy. This underscores the necessity for a deeper understanding of the molecular underpinnings of brain metastases, tumor microenvironment, and the identification of actionable biomarkers that can inform multimodal treatment approaches. The goal of this review is to synthesize current insights into the TME and elucidate molecular mechanisms in NSCLC brain metastases. Furthermore, we will explore the promising horizon of emerging biomarkers, both tissue- and liquid-based, that hold the potential to radically transform the treatment strategies and the enhancement of patient outcomes.

Regulating pri/pre-microRNA up/down expressed in cancer proliferation, angiogenesis and metastasis using selected potent triterpenoids

MicroRNAs (miRNAs) play a crucial role in cancer progression by selectively inducing translational degradation of messenger RNA (mRNA) via sequence-specific interactions with the 3'-untranslated region (3'-UTR). The potential targeting of miRNA has been recognized as a significant avenue for investigating the biological progression of diverse cancer types. Consequently, targeting of pri-miRNA and pre-miRNA by phytochemicals emerges as a viable strategy in the realm of anticancer therapies. Among phytochemicals, triterpenoids have garnered significant recognition for their chemotherapeutic and chemopreventive capabilities in combating multiple cancers. To date, there is a dearth of literature about the molecular interactions between triterpenoids and miRNAs. The primary objective of this investigation is to discern the potential triterpenoids that can function as modulators for specific miRNAs, namely pri-miRNA-19b-2, pre-miR21, microRNA 20b, pri-miRNA-208a, pri-miRNA-378a, pri-miRNA-320b-2, and pri-miRNA-300, achieved through the use of in silico investigations. The study primarily focused on performing drug-likeness, computer-aided toxicity, and pharmacokinetic prediction studies for triterpenoids. Furthermore, molecular docking and simulation techniques were employed to investigate these compounds. The triterpenoids studied were shown to have drug-likeness characteristics, although asiatic acid, lupeol, and pristimerin were able to pass all toxicity tests. Among the triterpenoids that underwent docking, pristimerin had a significant binding energy of -10.9 kcal/mol during its interaction with pri-miR-378a. The stable interaction between the pristimerin and miRNA complex was demonstrated by molecular dynamics simulation. As a result, pristimerin has the potential to act as a modulator of carcinogenic miRNAs, making it a promising candidate for cancer prevention and treatment due to its tailored modulation of miRNA activity.

The role of microRNAs in brain metastasis

Brain metastasis (BM) is the most common type of brain tumor and frequently foreshadows disease progression and poor overall survival with patients having a median survival of 6 months. 70,000 new cases of BM are diagnosed each year in the United States (US) and the incidence rate for BM is increasing with improved detection. MicroRNAs (miRNAs) are small non-coding RNAs that serve as critical regulators of gene expression and can act as powerful oncogenes and tumor suppressors. MiRNAs have been heavily implicated in cancer and proposed as biomarkers or therapeutic targets or agents. In this review, we summarize an extensive body of scientific work investigating the role of microRNAs in BM. We discuss miRNA dysregulation, functions, targets, and mechanisms of action in BM and present the current standing of miRNAs as biomarkers and potential therapeutics for BM. We conclude with future directions of miRNA basic and clinical research in BM.

The Role of Exosome-Derived microRNA on Lung Cancer Metastasis Progression

The high mortality from lung cancer is mainly attributed to the presence of metastases at the time of diagnosis. Despite being the leading cause of lung cancer death, the underlying molecular mechanisms driving metastasis progression are still not fully understood. Recent studies suggest that tumor cell exosomes play a significant role in tumor progression through intercellular communication between tumor cells, the microenvironment, and distant organs. Furthermore, evidence shows that exosomes release biologically active components to distant sites and organs, which direct metastasis by preparing metastatic pre-niche and stimulating tumorigenesis. As a result, identifying the active components of exosome cargo has become a critical area of research in recent years. Among these components are microRNAs, which are associated with tumor progression and metastasis in lung cancer. Although research into exosome-derived microRNA (exosomal miRNAs) is still in its early stages, it holds promise as a potential target for lung cancer therapy. Understanding how exosomal microRNAs promote metastasis will provide evidence for developing new targeted treatments. This review summarizes current research on exosomal miRNAs' role in metastasis progression mechanisms, focusing on lung cancer.

Immunotherapy and brain metastasis in lung cancer: connecting bench side science to the clinic

Brain metastases (BMs) are the most common form of intracranial malignant neoplasms in adults, with a profound impact on quality of life and traditionally associated with a dismal prognosis. Lung cancer accounts for approximately 40%-50% of BM across different tumors. The process leading to BMs is complex and includes local invasion, intravasation, tumor cells circulation into the bloodstream, disruption of the blood-brain barrier, extravasation of tumor cells into the brain parenchyma, and interaction with cells of the brain microenvironment, among others. Once the tumor cells have seeded in the brain parenchyma, they encounter different glial cells of the brain, as well as immune cells. The interaction between these cells and tumor cells is complex and is associated with both antitumoral and protumoral effects. To overcome the lethal prognosis associated with BMs, different treatment strategies have been developed, such as immunotherapy with immune checkpoint inhibitors, particularly inhibitors of the PD-1/PD-L1 axis, which have demonstrated to be an effective treatment in both non-small cell lung cancer and small cell lung cancer. These antibodies have shown to be effective in the treatment of BM, alone or in combination with chemotherapy or radiotherapy. However, many unsolved questions remain to be answered, such as the sequencing of immunotherapy and radiotherapy, the optimal management in symptomatic BMs, the role of the addition of anti-CTLA-4 antibodies, and so forth. The complexity in the management of BMs in the era of immunotherapy requires a multidisciplinary approach to adequately treat this devastating event. The aim of this review is to summarize evidence regarding epidemiology of BM, its pathophysiology, current approach to treatment strategies, as well as future perspectives.

Upregulated miR‑378a‑3p expression suppresses energy metabolism and promotes apoptosis by targeting a GLUT‑1/ALDOA/PKM2 axis in esophageal carcinoma

Esophageal squamous cell carcinoma (ESCC) is an aggressive malignancy of the digestive system with increasing incidence and mortality rates. The biological roles of microRNA (miR)-378a-3p in tumor cells remain contested, and the mechanisms underlying the functions, energy metabolism, and cell survival mechanisms in ESCC cells are yet to be fully elucidated. In the present study, miR-378a-3p overexpression and negative control plasmids were transfected into ECA-109 cells using electroporation. Western blotting was used to detect the relative expression of proteins, and flow cytometry was used to detect cell apoptosis. Subsequently, ELISA assays were performed to determine enzyme activity, and an ATP detection kit was used to measure ATP content. Dual-luciferase reporter assays were performed to identify the target genes of miR-378a-3p. The results of the present study demonstrated that miR-378a-3p inhibited the gene expression and enzyme activities of glucose transporter protein 1 (GLUT-1), Aldolase A (ALDOA), and pyruvate kinase M2 (PKM2), all of which are involved in the glycolytic pathway of cells. Energy metabolism was suppressed by miR-378a-3p by reducing ATP content, and this downregulated the expression of Bcl-2 and Survivin. Moreover, increased miR-378a-3p expression promoted cell apoptosis in the early stages by increasing the expression levels and the activity of Bad and Caspase-3, while inhibiting the expression levels of Bcl-2 and Survivin. The results of the present study also demonstrated that GLUT-1/ALDOA/PKM2 were target genes of miR-378a-3p. Notably, miR-378a-3p blocked energy production and promoted the apoptosis of tumor cells via the downregulation of glycolytic enzyme expression and by reducing the mitochondrial membrane potential in ESCC. Bad, Caspase-3, Survivin, and Bcl-2 may be associated with blocking energy production and promoting apoptosis via miR-378a-3p in ESCC cells.

The origin of brain malignancies at the blood-brain barrier

Despite improvements in extracranial therapy, survival rate for patients suffering from brain metastases remains very poor. This is coupled with the incidence of brain metastases continuing to rise. In this review, we focus on core contributions of the blood-brain barrier to the origin of brain metastases. We first provide an overview of the structure and function of the blood-brain barrier under physiological conditions. Next, we discuss the emerging idea of a pre-metastatic niche, namely that secreted factors and extracellular vesicles from a primary tumor site are able to travel through the circulation and prime the neurovasculature for metastatic invasion. We then consider the neurotropic mechanisms that circulating tumor cells possess or develop that facilitate disruption of the blood-brain barrier and survival in the brain's parenchyma. Finally, we compare and contrast brain metastases at the blood-brain barrier to the primary brain tumor, glioma, examining the process of vessel co-option that favors the survival and outgrowth of brain malignancies.

Cell-Free miRNAs as Non-Invasive Biomarkers in Brain Tumors

Diagnosing brain tumors, especially malignant variants, such as glioblastoma, medulloblastoma, or brain metastasis, presents a considerable obstacle, while current treatment methods often yield unsatisfactory results. The monitoring of individuals with brain neoplasms becomes burdensome due to the intricate tumor nature and associated risks of tissue biopsies, compounded by the restricted accuracy and sensitivity of presently available non-invasive diagnostic techniques. The uncertainties surrounding diagnosis and the tumor's reaction to treatment can lead to delays in critical determinations that profoundly influence the prognosis of the disease. Consequently, there exists a pressing necessity to formulate and validate dependable, minimally invasive biomarkers that can effectively diagnose and predict brain tumors. Cell-free microRNAs (miRNAs), which remain stable and detectable in human bodily fluids, such as blood and cerebrospinal fluid (CSF), have emerged as potential indicators for a range of ailments, brain tumors included. Numerous investigations have showcased the viability of profiling cell-free miRNA expression in both CSF and blood samples obtained from patients with brain tumors. Distinct miRNAs demonstrate varying expression patterns within CSF and blood. While cell-free microRNAs in the blood exhibit potential in diagnosing, prognosticating, and monitoring treatment across diverse tumor types, they fall short in effectively diagnosing brain tumors. Conversely, the cell-free miRNA profile within CSF demonstrates high potential in delivering precise and specific evaluations of brain tumors.

MicroRNA‑378: An important player in cardiovascular diseases (Review)

Cardiovascular disease (CVD) is a common chronic clinical condition and is the main cause of death in humans worldwide. Understanding the genetic and molecular mechanisms involved in the development of CVD is essential to develop effective prevention strategies and therapeutic measures. An increasing number of CVD‑related genetic studies have been conducted, including those on the potential roles of microRNAs (miRs). These studies have demonstrated that miR‑378 is involved in the pathological processes of CVD, including those of myocardial infarction, heart failure and coronary heart disease. Despite the potential importance of miR‑378 CVD, a comprehensive summary of the related literature is lacking. Thus, the present review aimed to summarize the findings of previous studies on the roles and mechanisms of miR‑378 in a variety of CVDs and provide an up‑to date basis for further r research targeting the prevention and treatment of CVDs.

The Journey of Cancer Cells to the Brain: Challenges and Opportunities

Cancer metastases into the brain constitute one of the most severe, but not uncommon, manifestations of cancer progression. Several factors control how cancer cells interact with the brain to establish metastasis. These factors include mediators of signaling pathways participating in migration, infiltration of the blood-brain barrier, interaction with host cells (e.g., neurons, astrocytes), and the immune system. Development of novel therapies offers a glimpse of hope for increasing the diminutive life expectancy currently forecasted for patients suffering from brain metastasis. However, applying these treatment strategies has not been sufficiently effective. Therefore, there is a need for a better understanding of the metastasis process to uncover novel therapeutic targets. In this review, we follow the journey of various cancer cells from their primary location through the diverse processes that they undergo to colonize the brain. These processes include EMT, intravasation, extravasation, and infiltration of the blood-brain barrier, ending up with colonization and angiogenesis. In each phase, we focus on the pathways engaging molecules that potentially could be drug target candidates.

Advances in the Molecular Landscape of Lung Cancer Brain Metastasis

Lung cancer is one of the most frequent tumors that metastasize to the brain. Brain metastasis (BM) is common in advanced cases, being the major cause of patient morbidity and mortality. BMs are thought to arise via the seeding of circulating tumor cells into the brain microvasculature. In brain tissue, the interaction with immune cells promotes a microenvironment favorable to the growth of cancer cells. Despite multimodal treatments and advances in systemic therapies, lung cancer patients still have poor prognoses. Therefore, there is an urgent need to identify the molecular drivers of BM and clinically applicable biomarkers in order to improve disease outcomes and patient survival. The goal of this review is to summarize the current state of knowledge on the mechanisms of the metastatic spread of lung cancer to the brain and how the metastatic spread is influenced by the brain microenvironment, and to elucidate the molecular determinants of brain metastasis regarding the role of genomic and transcriptomic changes, including coding and non-coding RNAs. We also present an overview of the current therapeutics and novel treatment strategies for patients diagnosed with BM from NSCLC.

Anticarcinogenic impact of extracellular vesicles (exosomes) from cord blood stem cells in malignant melanoma: A potential biological treatment

Incidence of Malignant Melanoma has become the 5th in the UK. To date, the major anticancer therapeutics include cell therapy, immunotherapy, gene therapy and nanotechnology-based strategies. Recently, extracellular vesicles, especially exosomes, have been highlighted for their therapeutic benefits in numerous chronic diseases. Exosomes display multifunctional properties, including inhibition of cancer cell proliferation and initiation of apoptosis. In the present in vitro study, the antitumour effect of cord blood stem cell (CBSC)-derived exosomes was confirmed by the CCK-8 assay (p < 0.05) on CHL-1 melanoma cells and improve the repair mechanism on lymphocytes from melanoma patients. Importantly, no significant effect was observed in healthy lymphocytes when treated with the exosome concentrations at 24, 48 and 72 h. Comet assay results (OTM and %Tail DNA) demonstrated that the optimal exosome concentration showed a significant impact (p < 0.05) in lymphocytes from melanoma patients whilst causing no significant DNA damage in lymphocytes of healthy volunteers was 300 μg/ml. Similarly, the Comet assay results depicted significant DNA damage in a melanoma cell line (CHL-1 cells) treated with CBSC-derived exosomes, both the cytotoxicity of CHL-1 cells treated with CBSC-derived exosomes exhibited a significant time-dependent decrease in cell survival. Sequencing analysis of CBSC exosomes showed the presence of the let-7 family of miRNAs, including let-7a-5p, let-7b-5p, let-7c-5p, let-7d-3p, let-7d-5p and two novel miRNAs. The potency of CBSC exosomes in inhibiting cancer progression in lymphocytes from melanoma patients and CHL-1 cells whilst causing no harm to the healthy lymphocytes makes it a potential candidate as an anticancer therapy.

Depicting the Implication of miR-378a in Cancers

MicroRNA-378a (miR-378a), including miR-378a-3p and miR-378a-5p, are encoded in PPARGC1B gene. miR-378a is essential for tumorigenesis and is an independent prognostic biomarker for various malignant tumors. Aberrant expression of miR-378a affects several physiological and pathological processes, including proliferation, apoptosis, tumorigenesis, cancer invasion, metastasis, and therapeutic resistance. Interestingly, miR-378a has a dual functional role in either promoting or inhibiting tumorigenesis, independent of the cancer type. In this review, we comprehensively summarized the role and regulatory mechanisms of miR-378a in cancer development, hoping to provide a direction for its potential use in cancer therapy.

The Significance of MicroRNAs in the Molecular Pathology of Brain Metastases

Brain metastases are the most frequent intracranial tumors in adults and the cause of death in almost one-fourth of cases. The incidence of brain metastases is steadily increasing. The main reason for this increase could be the introduction of new and more efficient therapeutic strategies that lead to longer survival but, at the same time, cause a higher risk of brain parenchyma infiltration. In addition, the advances in imaging methodology, which provide earlier identification of brain metastases, may also be a reason for the higher recorded number of patients with these tumors. Metastasis is a complex biological process that is still largely unexplored, influenced by many factors and involving many molecules. A deeper understanding of the process will allow the discovery of more effective diagnostic and therapeutic approaches that could improve the quality and length of patient survival. Recent studies have shown that microRNAs (miRNAs) are essential molecules that are involved in specific steps of the metastatic cascade. MiRNAs are endogenously expressed small non-coding RNAs that act as post-transcriptional regulators of gene expression and thus regulate most cellular processes. The dysregulation of these molecules has been implicated in many cancers, including brain metastases. Therefore, miRNAs represent promising diagnostic molecules and therapeutic targets in brain metastases. This review summarizes the current knowledge on the importance of miRNAs in brain metastasis, focusing on their involvement in the metastatic cascade and their potential clinical implications.

MicroRNAs as Predictors of Lung-Cancer Resistance and Sensitivity to Cisplatin

Background: Platinum-based chemotherapy, cisplatin (DDP) specifically, is the main strategy for treating lung cancer (LC). However, currently, there is a lack of predictive drug-resistance markers, and there is increased interest in the development of a reliable and sensitive panels of markers for DDP chemotherapy-effectiveness prediction. MicroRNAs represent a perspective pool of markers for chemotherapy effectiveness. Objectives: Data on miRNAs associated with LC DDP chemotherapy response are summarized and analyzed. Materials and methods: A comprehensive review of the data in the literature and an analysis of bioinformatics resources were performed. The gene targets of miRNAs, as well as their reciprocal relationships with miRNAs, were studied using several databases. Results and Discussion: The complex analysis of bioinformatics resources and the literature indicated that the expressions of 12 miRNAs have a high predictive potential for LC DDP chemotherapy responses. The obtained information was discussed from the point of view of the main mechanisms of LC chemoresistance. Conclusions: An overview of the published data and bioinformatics resources, with respect to the predictive microRNA markers of chemotherapy response, is presented in this review. The selected microRNAs and gene panel have a high potential for predicting LC DDP sensitiveness or DDP resistance as well as for the development of a DDP co-therapy.

The role of miR-370 and miR-138 in the regulation of BMP2 suppressor gene expression in colorectal cancer: preliminary studies

PURPOSE

Colorectal cancer (CRC) is the fourth-most common cancer worldwide and the second most common cancer cause of death in the world. The components of the TGFβ-signalling pathway, which are often affected by miRNAs, are involved in the regulation of apoptosis and cell cycle. Therefore, in the current study, the expression of BMP2 gene in CRC tissues at different clinical stages compared to the non-tumour tissues has been assessed. Moreover, the plasma BMP2 protein concentration in the same group of CRC patients has been validated. Due to the constant necessity to conduct further research of the correlation between specific miRNAs and mRNAs in CRC, in silico analysis has been performed to select miRNAs that regulate BMP2 mRNA.

METHODS

The cDNA samples from tumor and non-tumor tissue were used in a qPCR reaction to determine the mRNA expression of the BMP2 gene and the expression of selected miRNAs. The concentration of BMP2 protein in plasma samples was also measured.

RESULTS

It was indicated that BMP2 was downregulated in CRC tissue. Moreover, miR-370 and miR-138 expression showed an upward trend. Decreased BMP2 with accompanied increasing miR-370 and miR-138 expression was relevant to the malignant clinicopathological features of CRC and consequently poor patient prognosis.

CONCLUSION

Our data suggest that miR-370 with its clear expression in plasma samples may be a potential diagnostic marker to determine the severity of the disease in patients at a later stage of colorectal cancer.

Dietary flavonoid narirutin as a prospective antagonist of oncogenic pri/pre-microRNAs

MicroRNAs (miRNAs) are involved in cancer progression via translational degradation in a sequence-specific manner of the 3'-untranslated region (3'UTR) of messenger RNA (mRNA). The involvement of miRNA in the biological progression of various cancer types is considered to be a potential target. Primary miRNA (pri-miRNA) and precursor-miRNA (pre-miRNA) synthesize the miRNA by dicer-catalyzed processes thus targeting pri/pre-miRNA by phytochemicals is amongst the appropriate approaches for anticancer therapies. Flavonoids category of phytochemicals is well-known for its chemotherapeutic and chemopreventive potential against multiple cancer types. However, the molecular interactions of flavonoids with miRNAs are not reported so far. Thus, this study aims to identify the promising flavonoids as the antagonist of miRNAs (pre-miR21, pri-miR-208a, pri-miR-378a, pri-miR320b, pri-miR-300, pri-miR-19b, and pre-miR-20b) using molecular docking simulations studies. Among the tested flavonoids, narirutin showed highest binding energy (-11.7 kcal/mol) against pri-miR19b followed by pri-miR-378a (-11.4 kcal/mol) >  pri-miR320b (-11.2 kcal/mol) =  pri-miR-300 (-11.2 kcal/mol) >  pri-miR-208a (-9.0 kcal/mol) >  pre-miR-20b (- 8.3 kcal/mol). The molecular dynamic simulation experiment confirmed that narirutin destabilizes the tertiary structure of pri-miRNA in comparison to apo-RNA. The finding indicates that narirutin binding with pre-miRNA causes disruption of pri-RNA structure that creates a loss of DICER-pre-miRNA interactions by hindering the pre-miRNA synthesis, thereby affecting miRNA processing. Further pharmacokinetics and toxicity prediction revealed that it is non-carcinogenic, non-mutagenic, and does not inhibit the CYPs activity. Thus, narirutin could be a possible antagonist of oncogenic miRNAs, therefore could be useful for miRNA-targeted cancer prevention and treatment.

Clinical Biomarkers for Early Identification of Patients with Intracranial Metastatic Disease

Simple Summary

The development of brain metastases, or intracranial metastatic disease (IMD), is a serious and life-altering complication for many patients with cancer. While there have been substantial advancements in the treatments available for IMD and in our understanding of its pathogenesis, conventional methods remain insufficient to detect IMD at an early stage. In this review, we discuss current research on biomarkers specific to IMD. In particular, we highlight biomarkers that can be easily accessed via the bloodstream or cerebrospinal fluid, including circulating tumor cells and DNA, as well as advanced imaging techniques. The continued development of these assays could enable clinicians to detect IMD prior to the development of IMD-associated symptoms and ultimately improve patient prognosis and survival.

Abstract

Nearly 30% of patients with cancer will develop intracranial metastatic disease (IMD), and more than half of these patients will die within a few months following their diagnosis. In light of the profound effect of IMD on survival and quality of life, there is significant interest in identifying biomarkers that could facilitate the early detection of IMD or identify patients with cancer who are at high IMD risk. In this review, we will highlight early efforts to identify biomarkers of IMD and consider avenues for future investigation.

CircRNA PLOD2 enhances ovarian cancer propagation by controlling miR-378

It has been confirmed that circular RNA participates in tumorgenesis through a variety of ways, so it may be used as a molecular marker for tumor diagnosis and treatment. In this study, the expression of circ-LOPD2 in ovarian cancer tissues and cell lines was detected by qRT-PCR and Western blot. The dual luciferase report was used to verify the target of circ-LOPD2, and the silencing and overexpression of circ-CSPP1 in cell lines was used to explore its relationship with miRNA-378. The cell proliferation was detected by CCK8 method, and the expression level of miRNA-378 was detected by qRT-PCR. The results showed that circ-LOPD2 was highly expressed in ovarian cancer (OC) tissues, circ-LOPD2 expression levels were higher in OVCAR3 and A2780, and circ-LOPD2 expression levels in CAOV3 were lower. After silencing circ-LOPD2, the growth ability of OVCAR3 and A2780 cells decreased, while overexpression of circ-LOPD2 led to the opposite result. We also found that miR-378 is a target of circ-LOPD2. Silencing circ-LOPD2 will increase the expression of miR-378, and overexpression of circ-LOPD2 will decrease the expression of miR-378. In summary, our results show that circ-LOPD2 as a miR-378 sponge promotes the proliferation of ovarian cancer cells, which may in turn promote the development of OC.

Bone Marrow-Derived Mesenchymal Stem Cells (BMSCs)-Derived MicroRNA-378a-3p (miR-378a-3p) Inhibits the Migration of Gestational Trophoblast Cells and Epithelial Mesenchymal Transition via Regulating X-Linked Inhibitor of Apoptosis Protein (XIAP) Pathway

The components of the in vivo microenvironment are BMSCs and miRNAs that have a critical role in the development of pregnancy. Our aim was to further investigate the effect of the miRNAs of BMSC origin on pregnancy injury. Exosomal miR-378a-3p secreted by BMSCs was identified by electron microscopy and miR-378a-3p expression was measured during gestational injury. Target scan detects the correlation of XIAP and miR-378a-3p which was confirmed by luciferase activity along with analysis of cell growth by MTT assay and cell invasion by Transwell and EMT expression. Exosomal miR-378a-3p derived from BMSCs promoted proliferation and migration and invasion of trophoblast. miR-378a-3p targeted XIAP and its overexpression could significantly increase EMT switching. The miR-378a-3p/XIAP axis is critical in trophoblastic cell migration and EMT and is involved in pregnancy injury progression, indicating that it might be a novel potential target for the treatment of pregnancy injury.

Cancer driver gene and non-coding RNA alterations as biomarkers of brain metastasis in lung cancer: A review of the literature

Brain metastasis (BM) is the most common event in patients with lung cancer. Despite multimodal treatments and advances in systemic therapies, development of BM remains one of the main factors associated with poor prognosis and mortality in patients with lung cancer. Therefore, better understanding of mechanisms involved in lung cancer brain metastasis (LCBM) is of great importance to suppress cancer cells and to improve the overall survival of patients. Several cancer-related genes such as EGFR and KRAS have been proposed as potential predictors of LCBM. In addition, there is ample evidence supporting crucial roles of non-coding RNAs (ncRNAs) in mediating LCBM. In this review, we provide comprehensive information on risk assessment, predictive, and prognostic panels for early detection of BM in patients with lung cancer. Moreover, we present an overview of LCBM molecular mechanisms, cancer driver genes, and ncRNAs which may predict the risk of BM in lung cancer patients. Recent clinical studies have focused on determining mechanisms involved in LCBM and their association with diagnosis, prognosis, and treatment outcomes. These studies have shown that alterations in EGFR, KRAS, BRAF, and ALK, as the most frequent coding gene alterations, and dysregulation of ncRNAs such as miR-423, miR-330-3p, miR-145, piR-651, and MALAT1 can be considered as potential biomarkers of LCBM.

The role of exosomes in lung cancer metastasis and clinical applications: an updated review

Lung cancer is the leading cause of cancer-associated deaths accounting for 24% of all cancer deaths. As a crucial phase of tumor progression, lung cancer metastasis is linked to over 70% of these mortalities. In recent years, exosomes have received increasing research attention in their role in the induction of carcinogenesis and metastasis in the lung. In this review, recent studies on the contribution of exosomes to lung cancer metastasis are discussed, particularly highlighting the role of lung tumor-derived exosomes in immune system evasion, epithelial-mesenchymal transition, and angiogenesis, and their involvement at both the pre-metastatic and metastatic phases. The clinical application of exosomes as therapeutic drug carriers, their role in antitumor drug resistance, and their utility as predictive biomarkers in diagnosis and prognosis are also presented. The metastatic activity, a complex multistep process of cancer cell invasion, survival in blood vessels, attachment and subsequent colonization of the host's organs, is integrated with exosomal effects. Exosomes act as functional mediating factors in cell-cell communication, influencing various steps of the metastatic cascade. To this end, lung cancer cell-derived exosomes enhance cell proliferation, angiogenesis, and metastasis, regulate drug resistance, and antitumor immune activities during lung carcinogenesis, and are currently being explored as an important component in liquid biopsy assessment for diagnosing lung cancer. These nano-sized extracellular vesicles are also being explored as delivery vehicles for therapeutic molecules owing to their unique properties of biocompatibility, circulatory stability, decreased toxicity, and tumor specificity. The current knowledge of the role of exosomes highlights an array of exosome-dependent pathways and cargoes that are ripe for exploiting therapeutic targets to treat lung cancer metastasis, and for predictive value assessment in diagnosis, prognosis, and anti-tumor drug resistance.

Epigenetic regulation of angiogenesis in lung cancer

Lung cancer is the leading cause of cancer-related deaths worldwide, in which angiogenesis is highly required for lung cancer cell growth and metastasis. Genetic regulation of this multistep process is being studied extensively, however, relatively less is known about the epigenetic regulation of angiogenesis in lung cancer. Several epigenetic alterations contribute to regulating angiogenesis, such as epimodifications of DNA, posttranslational modification of histones, and expression of noncoding RNAs. Here, we review the current knowledge of the epigenetic regulation of angiogenesis and discuss the potential clinical applications of epigenetic-based anticancer therapy in lung cancer. Overall, epigenetic-based therapy will likely emerge as a prominent approach to treat lung cancer in the future.

MicroRNA-378a-3p contributes to ovarian cancer progression through downregulating PDIA4

OBJECTIVE

MicroRNAs, as essential players in tumorigenesis, have been demonstrated to have a revolutionary effect on human cancer research. Ovarian cancer is the primary reason of death among gynecologic malignancies. In view of this, it is significant to identify prognostic and predictive markers for treatment of ovarian cancer. The aim of this study was to probe into the effects of miR-378a-3p and protein disulfide-isomerase A4 (PDIA4) on the biological functions of ovarian cancer cells.

METHODS

miR-378a-3p expression and PDIA4 messenger RNA expression in human ovarian cancer cells, normal human ovarian epithelial cells, and serum of both ovarian cancer patients and healthy people were detected by reverse transcription-quantitative polymerase chain reaction, and the PDIA4 protein expression was tested by Western blot analysis. Ovarian cancer OVCAR3 and SKOV3 cells were transfected or cotransfected with miR-378a-3p mimic or pcDNA3.1-PDIA4 or their negative control plasmids to explore their roles in biological functions in ovarian cancer cells. Luciferase activity and RIPA assays were implemented to validate the interaction between miR-378a-3p and PDIA4. Western blot analysis was utilized to detect phosphatidylinositol-3 kinase/serine/threonine kinase (PI3K/AKT) signaling pathway-related protein expression and their phosphate expression levels.

RESULTS

miR-378a-3p was elevated and PDIA4 was decreased in ovarian cancer cells and serum. In addition, miR-378a-3p mimic induced ovarian cancer cell growth, while miR-378a-3p inhibitor and pcDNA3.1-PDIA4 presented an inverse trend. pcDNA3.1-PDIA4 partially eliminated the capabilities of miR-378a-3p mimic on ovarian cancer progression. Meanwhile, miR-378a-3p was found to negatively regulate PDIA4, and miR-378a-3p mimic increased the phosphorylation levels of AKT and PI3K, while pcDNA3.1-PDIA4 exhibited an opposite tendency. Furthermore, pcDNA3.1-PDIA4 largely eliminated the functions of miR-378a-3p mimic on phosphorylation levels of AKT and PI3K.

CONCLUSION

This study provides evidences that miR-378a-3p activates PI3K/AKT signaling pathway by modulating PDIA4 expression, thereby playing a role in promoting the growth of ovarian cancer cells. This study provides novel directions for targeted therapy of ovarian cancer.

miR-378a influences vascularization in skeletal muscles

AIMS

MicroRNA-378a, highly expressed in skeletal muscles, was demonstrated to affect myoblasts differentiation and to promote tumour angiogenesis. We hypothesized that miR-378a could play a pro-angiogenic role in skeletal muscle and may be involved in regeneration after ischaemic injury in mice.

METHODS AND RESULTS

Silencing of miR-378a in murine C2C12 myoblasts did not affect differentiation but impaired their secretory angiogenic potential towards endothelial cells. miR-378a knockout (miR-378a-/-) in mice resulted in a decreased number of CD31-positive blood vessels and arterioles in gastrocnemius muscle. In addition, diminished endothelial sprouting from miR-378a-/- aortic rings was shown. Interestingly, although fibroblast growth factor 1 (Fgf1) expression was decreased in miR-378a-/- muscles, this growth factor did not mediate the angiogenic effects exerted by miR-378a. In vivo, miR-378a knockout did not affect the revascularization of the ischaemic muscles in both normo- and hyperglycaemic mice subjected to femoral artery ligation (FAL). No difference in regenerating muscle fibres was detected between miR-378a-/- and miR-378+/+ mice. miR-378a expression temporarily declined in ischaemic skeletal muscles of miR-378+/+ mice already on Day 3 after FAL. At the same time, in the plasma, the level of miR-378a-3p was enhanced. Similar elevation of miR-378a-3p was reported in the plasma of patients with intermittent claudication in comparison to healthy donors. Local adeno-associated viral vectors-based miR-378a overexpression was enough to improve the revascularization of the ischaemic limb of wild-type mice on Day 7 after FAL, what was not reported after systemic delivery of vectors. In addition, the number of infiltrating CD45+ cells and macrophages (CD45+ CD11b+ F4/80+ Ly6G-) was higher in the ischaemic muscles of miR-378a-/- mice, suggesting an anti-inflammatory action of miR-378a.

CONCLUSIONS

Data indicate miR-378a role in the pro-angiogenic effect of myoblasts and vascularization of skeletal muscle. After the ischaemic insult, the anti-angiogenic effect of miR-378a deficiency might be compensated by enhanced inflammation.

microRNAs Biogenesis, Functions and Role in Tumor Angiogenesis

microRNAs (miRNAs) are small non-coding RNA molecules, evolutionary conserved. They target more than one mRNAs, thus influencing multiple molecular pathways, but also mRNAs may bind to a variety of miRNAs, either simultaneously or in a context-dependent manner. miRNAs biogenesis, including miRNA transcription, processing by Drosha and Dicer, transportation, RISC biding, and miRNA decay, are finely controlled in space and time. miRNAs are critical regulators in various biological processes, such as differentiation, proliferation, apoptosis, and development in both health and disease. Their dysregulation is involved in tumor initiation and progression. In tumors, they can act as onco-miRNAs or oncosuppressor-miRNA participating in distinct cellular pathways, and the same miRNA can perform both activities depending on the context. In tumor progression, the angiogenic switch is fundamental. miRNAs derived from tumor cells, endothelial cells, and cells of the surrounding microenvironment regulate tumor angiogenesis, acting as pro-angiomiR or anti-angiomiR. In this review, we described miRNA biogenesis and function, and we update the non-classical aspects of them. The most recent role in the nucleus, as transcriptional gene regulators and the different mechanisms by which they could be dysregulated, in tumor initiation and progression, are treated. In particular, we describe the role of miRNAs in sprouting angiogenesis, vessel co-option, and vasculogenic mimicry. The role of miRNAs in lymphoma angiogenesis is also discussed despite the scarcity of data. The information presented in this review reveals the need to do much more to discover the complete miRNA network regulating angiogenesis, not only using high-throughput computational analysis approaches but also morphological ones.

Beyond Conventional: The New Horizon of Anti-Angiogenic microRNAs in Non-Small Cell Lung Cancer Therapy

GLOBOCAN 2018 identified lung cancer as the leading oncological pathology in terms of incidence and mortality rates. Angiogenesis is a key adaptive mechanism of numerous malignancies that promotes metastatic spread in view of the dependency of cancer cells on nutrients and oxygen, favoring invasion. Limitation of the angiogenic process could significantly hamper the disease advancement through starvation of the primary tumor and impairment of metastatic spread. This review explores the basic molecular mechanisms of non-small cell lung cancer (NSCLC) angiogenesis, and discusses the influences of the key proangiogenic factors-the vascular endothelial growth factor-A (VEGF-A), basic fibroblast growth factor (FGF2), several matrix metalloproteinases (MMPs-MMP-2, MMP-7, MMP-9) and hypoxia-and the therapeutic implications of microRNAs (miRNAs, miRs) throughout the entire process, while also providing critical reviews of a number of microRNAs, with a focus on miR-126, miR-182, miR-155, miR-21 and let-7b. Finally, current conventional NSCLC anti-angiogenics-bevacizumab, ramucirumab and nintedanib-are briefly summarized through the lens of evidence-based medicine.

MicroRNA-378 Suppressed Osteogenesis of MSCs and Impaired Bone Formation via Inactivating Wnt/β-Catenin Signaling

MicroRNAs (miRNAs) have been reported to serve as silencers to repress gene expression at post-transcriptional levels. Multiple miRNAs have been demonstrated to play important roles in osteogenesis. MicroRNA (miR)-378, a conserved miRNA, was reported to mediate bone metabolism and influence bone development, but the detailed function and underlying mechanism remain obscure. In this study, the miR-378 transgenic (TG) mouse was developed to study the role of miR-378 in osteogenic differentiation as well as bone formation. The abnormal bone tissues and impaired bone quality were displayed in the miR-378 TG mice, and a delayed healing effect was observed during bone fracture of the miR-378 TG mice. The osteogenic differentiation of mesenchymal stem cells (MSCs) derived from this TG mouse was also inhibited. We also found that miR-378 mimics suppressed, whereas anti-miR-378 promoted osteogenesis of human MSCs. Two Wnt family members, Wnt6 and Wnt10a, were identified as bona fide targets of miR-378, and their expression was decreased by this miRNA, which eventually induced the inactivation of Wnt/β-catenin signaling. Finally, the short hairpin (sh)-miR-378-modified MSCs were locally injected into the fracture sites in an established mouse fracture model. The results indicated that miR-378 inhibitor therapy could promote bone formation and stimulate the healing process in vivo. In conclusion, miR-378 suppressed osteogenesis and bone formation via inactivating Wnt/β-catenin signaling, suggesting that miR-378 may be a potential therapeutic target for bone diseases.

Unique miRNA profiling of squamous cell carcinoma arising from ovarian mature teratoma: comprehensive miRNA sequence analysis of its molecular background

Owing to its rarity, the carcinogenesis and molecular biological characteristics of squamous cell carcinoma arising from mature teratoma remain unclear. This study aims to elucidate the molecular background of malignant transformation from the aspects of microRNA (miRNA) profiling. We examined 7 patients with squamous cell carcinoma and 20 patients with mature teratoma and extracted their total RNA from formalin-fixed paraffin-embedded tissues. Then we prepared small RNA libraries and performed comprehensive miRNA sequencing. Heatmap and principal component analysis revealed markedly different miRNA profiling in cancer, normal ovarian and mature teratoma tissues. Then we narrowed down cancer-related miRNAs, comparing paired-cancer and normal ovaries. Comparisons of cancer and mature teratoma identified two markedly upregulated miRNAs (miR-151a-3p and miR-378a-3p) and two markedly downregulated miRNAs (miR-26a-5p and miR-99a-5p). In addition, these findings were validated in fresh cancer tissues of patient-derived xenograft (PDX) models. Moreover, several miRNAs, including miR-151a-3p and miR-378a-3p, were elevated in the murine plasma when tumor tissues were enlarged although miR-26a-5p and miR-99a-5p were not elucidated in the murine plasma. Finally, we performed target prediction and functional annotation analysis in silico and indicated that targets genes of these miRNAs markedly correlated with cancer-related pathways, including 'pathway in cancer' and 'cell cycle'. In conclusion, this is the first study on miRNA sequencing for squamous cell carcinoma arising from mature teratoma. The study identified four cancer-related miRNAs that were considered to be related to the feature of malignant transformation. Moreover, miRNAs circulating in the murine plasma of the PDX model could be novel diagnostic biomarkers.

Role of exosomal miR‑21 in the tumor microenvironment and osteosarcoma tumorigenesis and progression (Review)

Osteosarcoma is the most common bone tumor affecting both adolescents and children. Early detection is critical for the effective treatment of the disease. Derived from cancer cells, miR‑21 contained within exosomes in the tumor microenvironment may act on both cancer cells and the surrounding tumor microenvironment (TME), including immune cells, endothelial cells and fibroblasts. In human serum and plasm, the level of exosomal miR‑21 between osteosarcoma patients and healthy controls differs, supporting the role of miR‑21 as a biomarker for osteosarcoma. The involvement of a number of miR‑21 target genes in tumor progression suggests that miR‑21 may significantly affect the plasticity of cancer cells, leading to tumor progression, metastasis, angiogenesis and immune escape in osteosarcoma. Understanding the biogenesis and functions of exosomal miR‑21 is of great value for the diagnosis and therapy of cancer, including osteosarcoma. The present review discusses the role of miR‑21 in the tumor microenvironment, and in the development and progression of osteosarcoma, with an aim to summarize the functions of this miRNA in cancer.

microRNA-378a-5p iS a novel positive regulator of melanoma progression

Evaluating the expression levels of miR-378a-5p both in a large melanoma patient cohort from The Cancer Genome Atlas database and in melanoma patients from our Institute, we found that miR-378a-5p is upregulated in metastatic melanoma specimens. miR-378a-5p expression was also increased in melanoma cells resistant to target therapy, and decreased in response to drug treatment. We also demonstrated that overexpression of miR-378a-5p enhances in vitro cell invasion and migration, and facilitates the ability of melanoma cells to form de novo vasculogenic structures. While performing downstream targeting studies, we confirmed the ability of miR-378a-5p to modulate the expression of known target genes, such as SUFU, FUS-1, and KLF9. Luciferase-3′UTR experiments also identified STAMBP and HOXD10 as new miR-378a-5p target genes. MMP2 and uPAR, two HOXD10 target genes, were positively regulated by miR-378a-5p. Genetic and pharmacologic approaches inhibiting uPAR expression and activity evidenced that the in vitro tumor-promoting functions of miR-378a-5p, were in part mediated by uPAR. Of note miR-378a-5p was also able to increase VEGF, as well as in vitro and in vivo angiogenesis. Finally, genetic and pharmacologic modulation of Bcl-2 evidenced Bcl-2 ability to regulate miR-378a-5p expression. In conclusion, to the best of our knowledge, this is the first study demonstrating that miR-378a-5p acts as an oncogenic microRNA in melanoma.

Tumor microenvironment differences between primary tumor and brain metastases

The present review aimed to discuss contemporary scientific literature involving differences between the tumor microenvironment (TME) in melanoma, lung cancer, and breast cancer in their primary site and TME in brain metastases (BM). TME plays a fundamental role in the behavior of cancer. In the process of carcinogenesis, cells such as fibroblasts, macrophages, endothelial cells, natural killer cells, and other cells can perpetuate and progress carcinogenesis via the secretion of molecules. Oxygen concentration, growth factors, and receptors in TME initiate angiogenesis and are examples of the importance of microenvironmental conditions in the performance of neoplastic cells. The most frequent malignant brain tumors are metastatic in origin and primarily originate from lung cancer, breast cancer, and melanoma. Metastatic cancer cells have to adhere to and penetrate the blood-brain barrier (BBB). After traversing BBB, these cells have to survive by producing various cytokines, chemokines, and mediators to modify their new TME. The microenvironment of these metastases is currently being studied owing to the discovery of new therapeutic targets. In these three types of tumors, treatment is more effective in the primary tumor than in BM due to several factors, including BBB. Understanding the differences in the characteristics of the microenvironment surrounding the primary tumor and their respective metastasis might help improve strategies to comprehend cancer.

Hypomethylation of MIR-378 5'-flanking region predicts poor survival in young patients with myelodysplastic syndrome

BACKGROUND

Previous studies have disclosed up-regulation of MIR-378 in acute myeloid leukemia (AML), and might consequently affect the outcome of the patients. Correspondingly, hypomethylation of MIR-378 was also identified in AML, particularly for FAB-M2 subtype with t(8;21) chromosomal translocation. Nevertheless, the methylation status of MIR-378 has not been illustrated in myelodysplastic syndrome (MDS). Herein we designed to understand the methylation pattern of MIR-378 involved in MDS and clinical interrelation thereof.

METHODS

Real-time quantitative methylation-specific PCR (RQ-MSP) was performed to evaluate the methylation degree of MIR-378 5'-flanking region on bone marrow mononuclear cells collected from 95 de novo MDS patients. Five gene mutations (IDH1, IDH2, DNMT3A, U2AF1, and SF3B1) were detected by high-resolution melting analysis to further evaluate the clinical relevance of hypomethylation of MIR-378.

RESULTS

Unmethylated level of MIR-378 5'-flanking region was significantly higher in MDS patients than that in controls (p = .034). Hypomethylated MIR-378 was identified in 20 of 95 (21%) cases with MDS. Male patients appeared to be more frequent to harbor MIR-378 hypomethylation compared to female patients (15/55, 27.3% vs. 4/40, 10.0%, p = .04). There was no significant difference in age, white blood cell counts, platelet counts, hemoglobin concentration, and karyotypes between the patients with and without MIR-378-hypomethylation. Distinct distribution of five gene mutations was not observed in the two groups as well. However, MIR-378-hypomethylated patients had significantly shorter overall survival than those without MIR-378 hypomethylation (p = .036). Moreover, among patients <60 years, hypomethylation of MIR-378 was confirmed to be an independent adverse prognostic factor by both Kaplan-Meier and Multivariate Cox analyses.

CONCLUSION

Hypomethylation of MIR-378 5'-flanking region is an adverse prognosticator in MDS, particularly in patients <60 years.

MicroRNAs in non-small cell lung cancer: Gene regulation, impact on cancer cellular processes, and therapeutic potential

Lung cancer remains the most lethal cancer among men and women in the United States and worldwide. The majority of lung cancer cases are classified as non-small cell lung cancer (NSCLC). Developing new therapeutics on the basis of better understanding of NSCLC biology is critical to improve the treatment of NSCLC. MicroRNAs (miRNAs or miRs) are a superfamily of genome-derived, small noncoding RNAs that govern posttranscriptional gene expression in cells. Functional miRNAs are commonly dysregulated in NSCLC, caused by genomic deletion, methylation, or altered processing, which may lead to the changes of many cancer-related pathways and processes, such as growth and death signaling, metabolism, angiogenesis, cell cycle, and epithelial to mesenchymal transition, as well as sensitivity to current therapies. With the understanding of miRNA biology in NSCLC, there are growing interests in developing new therapeutic strategies, namely restoration of tumor suppressive miRNAs and inhibition of tumor promotive miRNAs, to combat against NSCLC. In this article, we provide an overview on the molecular features of NSCLC and current treatment options with a focus on pharmacotherapy and personalized medicine. By illustrating the roles of miRNAs in the control of NSCLC tumorigenesis and progression, we highlight the latest efforts in assessing miRNA-based therapies in animal models and discuss some critical challenges in developing RNA therapeutics.

Insights into the Regulation of Tumor Angiogenesis by Micro-RNAs

One of the hallmarks of cancer is angiogenesis, a series of events leading to the formation of the abnormal vascular network required for tumor growth, development, progression, and metastasis. MicroRNAs (miRNAs) are short, single-stranded, non-coding RNAs whose functions include modulation of the expression of pro- and anti-angiogenic factors and regulation of the function of vascular endothelial cells. Vascular-associated microRNAs can be either pro- or anti-angiogenic. In cancer, miRNA expression levels are deregulated and typically vary during tumor progression. Experimental data indicate that the tumor phenotype can be modified by targeting miRNA expression. Based on these observations, miRNAs may be promising targets for the development of novel anti-angiogenic therapies. This review discusses the role of various miRNAs and their targets in tumor angiogenesis, describes the strategies and challenges of miRNA-based anti-angiogenic therapies and explores the potential use of miRNAs as biomarkers for anti-angiogenic therapy response.

MicroRNA-330-3p promotes brain metastasis and epithelial-mesenchymal transition via GRIA3 in non-small cell lung cancer

Brain metastasis (BM) is associated with poor prognosis in patients with non-small cell lung cancer (NSCLC). We sought to identify microRNAs (miRNAs) that could serve as biomarkers to differentiate NSCLC patients with and without BM. Logistic regression was conducted with 122 NSCLC patients (60 without BM, 62 with BM) to assess the association between miRNAs and BM. We confirmed several risk factors for BM and revealed that serum miR-330-3p levels are higher in NSCLC patients with BM than that without BM. Overexpression of miR-330-3p promoted proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of NSCLC cells in vitro and NSCLC tumorigenesis in vivo. Knocking down miR-330-3p suppressed this metastatic phenotype. We identified putative miR-330-3p target genes by comparing mRNA microarray analysis data from A549 cells after miR-330-3p knockdown with candidate miR-330-3p target genes predicted by public bioinformatic tools and luciferase reporter assays. We found that GRIA3 is a target of miR-330-3p and that miR-330-3p stimulates EMT progress by mediating GRIA3-TGF-β1 interaction. Our results provide novel insight into the role of miR-330-3p in NSCLC metastasis, and suggest miR-330-3p may be a useful biomarker for identifying NSCLC with metastatic potential.

Co-delivery of VEGF siRNA and Etoposide for Enhanced Anti-angiogenesis and Anti-proliferation Effect via Multi-functional Nanoparticles for Orthotopic Non-Small Cell Lung Cancer Treatment

Targeting tumor angiogenesis pathway via VEGF siRNA (siVEGF) has shown great potential in treating highly malignant and metastatic non-small cell lung cancer (NSCLC). However, anti-angiogenic monotherapy lacked sufficient antitumor efficacy which suffered from malignant tumor proliferation. Therefore, the combined application of siVEGF and chemotherapeutic agents for simultaneous targeting of tumor proliferation and angiogenesis has been a research hotspot to explore a promising NSCLC therapy regimen.

Methods: We designed, for the first time, a rational therapy strategy via intelligently co-delivering siVEGF and chemotherapeutics etoposide (ETO) by multi-functional nanoparticles (NPs) directed against the orthotopic NSCLC. These NPs consisted of cationic liposomes loaded with siVEGF and ETO and then coated with versatile polymer PEGylated histidine-grafted chitosan-lipoic acid (PHCL). We then comprehensively evaluated the anti-angiogenic and anti-proliferation efficiency in the in vitro tumor cell model and in bioluminescent orthotopic lung tumor bearing mice model.

Results: The NPs co-delivering siVEGF and ETO exhibited tailor-made surface charge reversal features in mimicking tumor extracellular environment with improved internal tumor penetration capacity and higher cellular internalization. Furthermore, these NPs with flexible particles size triggered by intracellular acidic environment and redox environment showed pinpointed and sharp intracellular cargo release guaranteeing adequate active drug concentration in tumor cells. Enhanced VEGF gene expression silencing efficacy and improved tumor cell anti-proliferation effect were demonstrated in vitro. In addition, the PHCL layer improved the stability of these NPs in neutral environment allowing enhanced orthotopic lung tumor targeting efficiency in vivo. The combined therapy by siVEGF and ETO co-delivered NPs for orthotopic NSCLC simultaneously inhibited tumor proliferation and tumor angiogenesis resulting in more significant suppression of tumor growth and metastasis than monotherapy.

Conclusion: Combined application of siVEGF and ETO by the multi-functional NPs with excellent and on-demand properties exhibited the desired antitumor effect on the orthotopic lung tumor. Our work has significant potential in promoting combined anti-angiogenesis therapy and chemotherapy regimen for clinical NSCLC treatment.

Inferring the Disease-Associated miRNAs Based on Network Representation Learning and Convolutional Neural Networks

Identification of disease-associated miRNAs (disease miRNAs) are critical for understanding etiology and pathogenesis. Most previous methods focus on integrating similarities and associating information contained in heterogeneous miRNA-disease networks. However, these methods establish only shallow prediction models that fail to capture complex relationships among miRNA similarities, disease similarities, and miRNA-disease associations. We propose a prediction method on the basis of network representation learning and convolutional neural networks to predict disease miRNAs, called CNNMDA. CNNMDA deeply integrates the similarity information of miRNAs and diseases, miRNA-disease associations, and representations of miRNAs and diseases in low-dimensional feature space. The new framework based on deep learning was built to learn the original and global representation of a miRNA-disease pair. First, diverse biological premises about miRNAs and diseases were combined to construct the embedding layer in the left part of the framework, from a biological perspective. Second, the various connection edges in the miRNA-disease network, such as similarity and association connections, were dependent on each other. Therefore, it was necessary to learn the low-dimensional representations of the miRNA and disease nodes based on the entire network. The right part of the framework learnt the low-dimensional representation of each miRNA and disease node based on non-negative matrix factorization, and these representations were used to establish the corresponding embedding layer. Finally, the left and right embedding layers went through convolutional modules to deeply learn the complex and non-linear relationships among the similarities and associations between miRNAs and diseases. Experimental results based on cross validation indicated that CNNMDA yields superior performance compared to several state-of-the-art methods. Furthermore, case studies on lung, breast, and pancreatic neoplasms demonstrated the powerful ability of CNNMDA to discover potential disease miRNAs.

Circulating pro-angiogenic micro-ribonucleic acid in patients with coronary heart disease

OBJECTIVES

Our goal was to evaluate the expressions of 14 selected pro-angiogenic micro-ribonucleic acids in patients with coronary heart disease (CHD) and healthy controls (HCs) and to assess the correlations of those micro-ribonucleic acids with risk and severity of CHD.

METHODS

In the exploration stage, 20 patients with CHD were enrolled; in the validation stage, 102 patients with CHD and 92 age- and gender-matched HCs with the same eligibility of those in the exploration stage were recruited. Blood samples were collected from all participants, and plasma levels of micro-ribonucleic acids were measured by the quantitative polymerase chain reaction method.

RESULTS

In the exploration stage, the expression of miR-126, miR-17-5p, miR-19a, miR-92a, miR-210 and miR-378 in patients with CHD was down-regulated compared with that of HCs. In the validation stage, miR-126, miR-17-5p, miR-92a, miR-210 and miR-378 levels decreased remarkably in patients with CHD compared with the HCs. Plasma levels of miR-126, miR-17-5p, miR-92a, miR-210 and miR-378 were independent prediction factors for CHD. The combination of miR-126, miR-17-5p, miR-92a, miR-210 and miR-378 was of good diagnostic value for CHD with an area under the curve of 0.756. Additionally, plasma levels of miR-126, miR-210 and miR-378 correlated negatively with Gensini scores.

CONCLUSIONS

Circulating miR-126, miR-17-5p, miR-92a, miR-210 and miR-378 could serve as novel, promising biomarkers for risk and severity of CHD. Additionally, miR-126, miR-210 and miR-378 were negatively associated with Gensini scores.

PAQR4 promotes cell proliferation and metastasis through the CDK4-pRB-E2F1 pathway in non-small-cell lung cancer

Background

It is reported that progestin and adipoQ receptor 4 (PAQR4) has a tumorigenic effect on human breast cancer, but the role of PAQR4 in non-small-cell lung cancer (NSCLC) is unknown. The aim of this study was to investigate the role of PAQR4 in NSCLC.

Methods

Quantitative real-time PCR (qRT-PCR) and immunohistchemical (IHC) staining were used to analyze the expression of PAQR4 in HCC tissues and adjacent normal tissues. MTT, colony formation assay, flow cytometry (FCM), wound healing assays and transwell invasion assays were used to investigate the effects of PAQR4 on cell proliferation, colony formation, cell cycle, migration and invasion. Murine xenograft model assay was carried out to characterize the effects of PAQR4 knockdown on tumor growth in vivo.

Results

In this study, we found that the expression of PAQR4 was significantly upregulated in the NSCLC tissues of patients compared with that in the matched non-cancerous tissues. In addition, we found that PAQR4 was also significantly up-regulated in the NSCLC cell lines compared with normal human lung epithelial cells. Besides, we found that the over-expression of PAQR4 promoted promoted proliferation, colony formation, migration and invasion of the NSCLC cells, whereas the knockdown of PAQR4 inhibited proliferation, colony formation, migration and invasion of the NSCLC cells. Furthermore, mechanistic studies showed that the CDK4-pRB-E2F1 pathway was involved in NSCLC.

Conclusion

Hence, these results suggest that PAQR4 may be used as a new target in NSCLC therapy.

MicroRNA in Lung Cancer Metastasis

Tumor metastasis is a hallmark of cancer, with distant metastasis frequently developing in lung cancer, even at initial diagnosis, resulting in poor prognosis and high mortality. However, available biomarkers cannot reliably predict cancer spreading sites. The metastatic cascade involves highly complicated processes including invasion, migration, angiogenesis, and epithelial-to-mesenchymal transition that are tightly controlled by various genetic expression modalities along with interaction between cancer cells and the extracellular matrix. In particular, microRNAs (miRNAs), a group of small non-coding RNAs, can influence the transcriptional and post-transcriptional processes, with dysregulation of miRNA expression contributing to the regulation of cancer metastasis. Nevertheless, although miRNA-targeted therapy is widely studied in vitro and in vivo, this strategy currently affords limited feasibility and a few miRNA-targeted therapies for lung cancer have entered into clinical trials to date. Advances in understanding the molecular mechanism of metastasis will thus provide additional potential targets for lung cancer treatment. This review discusses the current research related to the role of miRNAs in lung cancer invasion and metastasis, with a particular focus on the different metastatic lesions and potential miRNA-targeted treatments for lung cancer with the expectation that further exploration of miRNA-targeted therapy may establish a new spectrum of lung cancer treatments.

MiR-378 promoted cell proliferation and inhibited apoptosis by enhanced stem cell properties in chronic myeloid leukemia K562 cells

Dysregulation of miR-378 has been found in diverse types of tumors as well as in leukemia. The role of miR-378 in chronic myeloid leukemia (CML) remains unclear. The aim of the study was to reveal the potential effects of miR-378 in the pathological process and progress in CML. Our results showed general level of miR-378 was significant higher in CML patients compared to controls. Overexpression of miR-378 dramatically promoted cell proliferation and drug-resistance. Additionally, apoptosis was inhibited in cells transfected with miR-378. More and bigger stem cell sphere formation was observed in miR-378 transfected cells. Furthermore, enhanced expression of miR-378 was associated with upregulation of stem-cell makers OCT4 and c-Myc. Further study validated that miR-378 inhibited the expression of FUS1. Our research demonstrated the oncogenic nature of miR-378 in CML, and might contribute to the progress of CML.

Molecular predictors of brain metastasis-related microRNAs in lung adenocarcinoma

Brain metastasis (BM) is a major complication of lung adenocarcinoma (LAD). An investigation of the pathogenic mechanisms of BM, as well as the identification of appropriate molecular markers, is necessary. The aim of this study was to determine the expression patterns of microRNAs (miRNAs) in LAD with BM, and to investigate the biological role of these miRNAs during tumorigenesis. miRNA array profiles were used to identify BM-associated miRNAs. These miRNAs were independently validated in 155 LAD patients. Several in vivo and in vitro assays were performed to verify the effects of miRNAs on BM. We identified six miRNAs differentially expressed in patients with BM as compared to patients with BM. Of these, miR-4270 and miR-423-3p were further investigated. miR-4270 and miR-423-3p directly targeted MMP19 and P21, respectively, to influence cell viability, migration, and colony formation in vitro. miR-4270 downregulation and miR-423-3p upregulation was associated with an increased risk of BM in LAD patients. Thus, our results suggested that miR-4270 and miR-423-3p might play an important role in BM pathogenesis in LAD patients, and that these miRNAs might be useful prognostic and clinical treatment targets.

Brain metastasis (BM) is a major complication of lung carcinoma. Here, we aimed to identify the key miRNAs involved in BM lung cancer. We first profiled miRNA expression in 32 tissues from NSCLC patients with BM and 55 tissues from NSCLC patients without BM. We independently validated our results in 68 additional tissues from NSCLC patients. Based on our results, we identified a panel of miRNAs that distinguish BM lung adenocarcinomas from non-BM We report here for the first time that either miR-4270 downregulation or miR-423-3p upregulation significantly increased cell proliferation, colony formation, and migration in vitro. miR-4270 and miR-423-3p increased the risk of BM in mouse models by targeting MMP19 and P21, respectively. Our results suggested that miR-4270 and miR-423-3p might be useful markers of BM in lung adenocarcinoma.

Down-regulation of miR-378a-3p induces decidual cell apoptosis: a possible mechanism for early pregnancy loss

STUDY QUESTION

Do microRNAs (miRNAs) contribute to human early pregnancy loss (EPL)?

SUMMARY ANSWER

miR-378a-3p expression is regulated by progesterone and is down-regulated in ducidua of EPL patients which may contribute to decidual apoptosis through Caspase-3 activation.

WHAT IS KNOWN ALREADY

A variety of miRNAs have been demonstrated to be associated with the development of decidualization and placental formation. However, little has been reported on the roles of miRNA in the pathogenesis of EPL.

STUDY DESIGN, SIZE, DURATION

Normal and EPL decidual tissues were collected from patients with normal pregnancies undergoing elective termination of gestation, and from patients with EPL, respectively.

PARTICIPANTS/MATERIALS, SETTING, METHODS

miRNA microarrays were used to identify the differentially expressed miRNAs between normal and EPL decidua, and miRNA expression was confirmed by qRT-PCR, qRT-PCR, western blotting and luciferase reporter assays were employed to validate the downstream targets of miR-378a-3p. The effects of miR-378a-3p were evaluated using miR-378a-3p-transfected decidual cells.

MAIN RESULTS AND THE ROLE OF CHANCE

Of note, 32 up-regulated miRNAs and 38 down-regulated miRNAs were identified by microarray analysis when comparing EPL to normal decidua. MiR-378a-3p was significantly down-regulated in the EPL decidua and was found to inversely regulate the expression of Caspase-3 by directly binding to its 3'-UTRs. In decidual cells, transfection of miR-378a-3p mimics resulted in the inhibition of cell apoptosis and in the increase of cell proliferation through Caspase-3 suppression. Moreover, we found that progesterone could induce the expression of miR-378a-3p in decidual cells.

LIMITATIONS, REASONS FOR CAUTION

This study focused on the function of miR-378a-3p and its target Caspase-3, however, numerous other targets and miRNAs may also be responsible for the pathogenesis of EPL. Therefore, further studies are required to elucidate the role of miRNAs in EPL.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings indicate that miR-378a-3p may contribute to the development of EPL, and that it could serve as a new potential predictive and therapeutic target of progesterone-treatment for EPL.

STUDY FUNDING/COMPETING INTEREST

This study was supported by National Basic Research Program of China (No.2012CB944900); National Science Foundation of China (No.31471405 and 81490742, No.81361120246); The National Science and Technology Support Program (No.2012BA132B00). Authors declare no competing interests.

MiR-378a-5p acts as a tumor suppressor in renal cell carcinoma and is associated with the good prognosis of patients

Renal cell carcinoma (RCC) is a common cancer that accounts for about 1.6% of all malignancies. Accumulating evidence has shown that miRNAs may play important roles in the development of cancers and that these same miRNAs may serve as diagnostic and prognostic biomarkers. The role of the miRNA miR-378a-5p in RCC, however, has been largely unexplored. In our study, we have demonstrated that miR-378a-5p expression was decreased in renal tissues and in RCC cell lines compared with corresponding expression levels in normal renal tissues and in the 293-T cell line. Functional studies in two RCC cell lines (ACHN and 786-O) have indicated that miR-378a-5p overexpression attenuated cell proliferation, migration, and invasion while promoting cell apoptosis. Inhibition of miR-378a-5p expression, on the other hand, promoted cell proliferation, migration, and invasion while reducing cell apoptosis. Additionally, in 42 cases of renal cancer formalin-fixed paraffin-embedded specimens, patients with higher expression levels of miR-378a-5p had significantly longer overall survival rates (P<0.05) than patients with lower miR-378a-5p expression levels. Thus, in this study, we have shown that miR-378a-5p can serve as a tumor suppressor and a potential prognostic biomarker in RCC.

Identification of potential biomarkers of lung adenocarcinoma brain metastases via microarray analysis of cDNA expression profiles

Brain metastases originating from lung adenocarcinoma (LAD) occur frequently. The aim of the current study was to assess potential biomarkers for the prognosis of lung adenocarcinoma brain metastasis (LAD-BM) through the analysis of gene expression microarrays. The current study downloaded two gene expression datasets, GSE14108 and GSE10245, from the Gene Expression Omnibus database. From GSE14108 and GSE10245, 19 LAD-BM samples and 40 primary LAD samples were selected for analysis. To identify the differentially expressed genes (DEGs), the current study compared the two sample groups, using the limma R package. Subsequently, pathway enrichment analysis was conducted using the Cluster Profiler R package, and the construction of the protein-protein interaction (PPI) network was executed utilizing the Search Tool for the Retrieval of Interacting Genes database. The microRNA-target network was built using the TargetScore R package. Then, these networks were established and visualized using Cytoscape software. An array of 463 DEGs was identified in the LAD-BM samples, including 256 upregulated and 207 downregulated genes. Based on functional term enrichment analysis using the Gene Ontology database and signaling pathway enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes database, it was identified that the overlapping DEGs were primarily involved in chemokine-associated signal transduction, which may mediate lung cancer cell metastasis to the brain. Chemokine ligand 2, lysozyme, matrix metalloproteinase-2 (MMP-2), lysyl oxidase (LOX) and granzyme B were identified as potential biomarkers according to a topological analysis of the PPI networks. Two notable nodes, MMP-2 and LOX, appeared in the PPI network and were key points in the microRNA-target network, as they were regulated by hsa-let-7d. Many DEGs and microRNAs were regarded as prognostic biomarkers for lung adenocarcinoma metastasis in the current study. These DEGs were primarily associated with chemokine-mediated signaling pathways. In addition, MMP-2 and LOX were predicted to be targets of hsa-let-7d.