The Significance of Microenvironmental and Circulating Lactate in Breast Cancer

Lactate represents the main product of pyruvate reduction catalyzed by the lactic dehydrogenase family of enzymes. Cancer cells utilize great quantities of glucose, shifting toward a glycolytic metabolism. With the contribution of tumor stromal cells and under hypoxic conditions, this leads toward the acidification of the extracellular matrix. The ability to shift between different metabolic pathways is a characteristic of breast cancer cells and is associated with an aggressive phenotype. Furthermore, the preliminary scientific evidence concerning the levels of circulating lactate in breast cancer points toward a correlation between hyperlactacidemia and poor prognosis, even though no clear linkage has been demonstrated. Overall, lactate may represent a promising metabolic target that needs to be investigated in breast cancer.

Association between dietary carotenoids intake and chronic constipation in American men and women adults: a cross-sectional study

BACKGROUND

Dietary carotenoids have been proven to improve intestinal disorders like inflammatory bowel disease and colon cancer, yet little is known about the link between dietary carotenoids and constipation. This study aims to examine the relationship between dietary carotenoids intake and constipation, using data from the National Health and Nutrition Examination Survey (NHANES) 2005-2010.

METHODS

A total of 11,722 participants were enrolled. Chronic constipation was defined as type 1 (separate hard lumps, like nuts) and type 2 (sausage-like, but lumpy) in the Bristol stool form scale (BSFS). Carotenoids intake was obtained from the average of two 24-hour dietary recall questionnaires (if only one 24-hour was available, we used it) and divided into quartiles (Q). The prevalence of constipation was calculated across men and women individuals. The relationship between dietary carotenoids intake and constipation in men and women was assessed with weighted logistic regression and smoothed curve fitting after adjusting confounders, with results displayed as weighted odds ratio (OR) with 95% confidence intervals (95% CI). The model was further stratified by age, race, and HEI 2015 scores (with median as cutoff) among men and women.

RESULTS

The total weighted prevalence of chronic constipation in this study was 8.08%, 11.11% in women and 5.18% in men. After multivariable adjustment, compared with the lowest intake, participants with the highest dietary lycopene intake (ORQ4 vs. Q1= 0.55, 95% CI: 0.36-0.84, p for trend = 0.01) and total lycopene intake (ORQ4 vs. Q1 = 0.52, 95% CI: 0.34-0.80, p for trend = 0.01) were negatively associated with the risk of chronic constipation in men, whereas increased dietary α-carotene intake reduced the risk of chronic constipation in women (ORQ4 vs. Q1 = 0.69, 95% CI: 0.48-0.98, p for trend = 0.04). Smoothing curve fitting further supported these results and provided evidence of dose-response effects. No association was found between other types of carotenoids and chronic constipation in men and women.

CONCLUSIONS

Increasing lycopene intake may improve bowel function in men while increased α-carotene intake may reduce the risk of chronic constipation in women. Further studies are essential to explore the role that the intake of carotenoids plays in chronic constipation.

Sustained activation of non-canonical NF-κB signalling drives glycolytic reprogramming in doxorubicin-resistant DLBCL

DLBCL is the most common lymphoma with high tumor heterogeneity. Treatment refractoriness and relapse from R-CHOP therapy in patients remain a clinical problem. Activation of the non-canonical NF-κB pathway is associated with R-CHOP resistance. However, downstream targets of non-canonical NF-κB mediating R-CHOP-induced resistance remains uncharacterized. Here, we identify the common mechanisms underlying both intrinsic and acquired resistance that are induced by doxorubicin, the main cytotoxic component of R-CHOP. We performed global transcriptomic analysis of (1) a panel of resistant versus sensitive and (2) isogenic acquired doxorubicin-resistant DLBCL cell lines following short and chronic exposure to doxorubicin respectively. Doxorubicin-induced stress in resistant cells activates a distinct transcriptional signature that is enriched in metabolic reprogramming and oncogenic signalling. Selective and sustained activation of non-canonical NF-κB signalling in these resistant cells exacerbated their survival by augmenting glycolysis. In response to doxorubicin, p52-RelB complexes transcriptionally activated multiple glycolytic regulators with prognostic significance through increased recruitment at their gene promoters. Targeting p52-RelB and their targets in resistant cells increased doxorubicin sensitivity in vitro and in vivo. Collectively, our study uncovered novel molecular drivers of doxorubicin-induced resistance that are regulated by non-canonical NF-κB pathway. We reveal new avenues of therapeutic targeting for R-CHOP-treated refractory/relapsed DLBCL patients.

Metabolic Pathways in Breast Cancer Reprograming: An Insight to Non-Coding RNAs

Cancer cells reprogram their metabolisms to achieve high energetic requirements and produce precursors that facilitate uncontrolled cell proliferation. Metabolic reprograming involves not only the dysregulation in glucose-metabolizing regulatory enzymes, but also the enzymes engaging in the lipid and amino acid metabolisms. Nevertheless, the underlying regulatory mechanisms of reprograming are not fully understood. Non-coding RNAs (ncRNAs) as functional RNA molecules cannot translate into proteins, but they do play a regulatory role in gene expression. Moreover, ncRNAs have been demonstrated to be implicated in the metabolic modulations in breast cancer (BC) by regulating the metabolic-related enzymes. Here, we will focus on the regulatory involvement of ncRNAs (microRNA, circular RNA and long ncRNA) in BC metabolism, including glucose, lipid and glutamine metabolism. Investigation of this aspect may not only alter the approaches of BC diagnosis and prognosis, but may also open a new avenue in using ncRNA-based therapeutics for BC treatment by targeting different metabolic pathways.

Retinoic Acid Downregulates HSPB8 Gene Expression in Human Breast Cancer Cells MCF-7

Breast cancer (BC) is a serious and widespread disease for which different treatments have been developed. In addition to the classic therapies, the treatment with retinoic acid (RA) is still being clinically investigated. RA reduces cancer cells proliferation and migration, but its molecular mechanism of action is not clear. In tumor development, autophagy promotes cancer cell survival and prevents apoptosis. Small heat shock protein B8 (HSPB8) acts together with its co-chaperone BCL-2 associated athanogene 3 (BAG3) stimulating BC proliferation and migration. We analyzed whether direct correlations exist between RA and HSPB8 or BAG3 and how this may play a role in BC. We measured HSPB8 and BAG3 gene expression in MCF-7 BC cells and we analyzed the potential correlation between the antiproliferative and antimigratory effect of RA with the expression level of HSPB8. We found that in MCF-7 cells RA reduces both HSPB8 and BAG3 gene expression and it alters the mitotic spindle organization. Notably, the effects of RA on HSPB8 levels are exerted at both transcriptional and translational levels. RA effects are possibly mediated by miR-574-5p that targets the HSPB8 transcript. Our results suggest that therapeutic doses of RA can efficiently counteract the adverse effects of HSPB8 in BC progression.

Icariin stimulates osteogenesis and suppresses adipogenesis of human bone mesenchymal stem cells via miR-23a-mediated activation of the Wnt/β-catenin signaling pathway

BACKGROUND

Icariin (ICA) is a bioactive compound isolated from epimedium-derived flavonoids that modulates bone mesenchymal stem cell osteogenesis and adipogenesis. However, its precise mechanism in this process is unknown.

PURPOSE

The purpose of this study was to elucidate the role of ICA on human bone mesenchymal stem cell (hBMSC) osteogenesis and adipogenesis by focusing on miR-23a mediated activation of the Wnt/β-catenin signaling pathway.

METHODS

After ICA treatment, hBMSC osteogenesis and adipogenesis were evaluated using alkaline phosphatase staining, an alkaline phosphatase activity assay, Oil Red O staining, and cellular triglyceride levels. Moreover, the mRNA and protein expression levels of osteogenic and adipogenic markers as well as key factors of the Wnt/β-catenin signaling pathway were measured using quantitative reverse transcription polymerase chain reaction and western blotting. Lithium chloride, an activator of the Wnt/β-catenin signaling pathway, was used as a positive control. Finally, to investigate the role of miR-23a in ICA-induced activation of the Wnt/β-catenin signaling pathway, hBMSCs were transfected with miR-23a mimics or a miR-23a inhibitor.

RESULTS

ICA significantly promoted hBMSC osteogenic differentiation by upregulating alkaline phosphatase activity and the expression of bone sialoprotein II (BSPII) and runt-related transcription factor-2 (Runx-2). In contrast, ICA inhibited hBMSC adipogenic differentiation by reducing lipid droplet formation and cellular triglyceride levels as well as by downregulating the expression of peroxisome proliferator-activated receptor-γ (PPAR-γ) and CCAAT enhancer-binding protein-α (C/EBP-α). ICA mediated its effects on hBMSCs by activating the Wnt/β-catenin signaling pathway. It did so by upregulating β-catenin, low density lipoprotein receptor-related protein 5 (LRP5), and T cell factor 1 (TCF1). Notably, the up-regulation of these proteins was blocked by Dickkopf-related protein 1 (DKK1). Critically, the effects of ICA on hBMSCs were similar to that of the positive control, lithium chloride. Notably, ICA-induced activation of the Wnt/β-catenin signaling pathway was significantly attenuated following miR-23a up-regulation. Conversely, miR-23a downregulation affected hBMSCs in the same manner as ICA; i.e., it activated the Wnt/β-catenin signaling pathway.

CONCLUSION

ICA promotes and inhibits, respectively, hBMSC osteogenesis and adipogenesis via miR-23a-mediated activation of the Wnt/β-catenin signaling pathway.

Quercetin Antagonizes Glucose Fluctuation Induced Renal Injury by Inhibiting Aerobic Glycolysis via HIF-1α/miR-210/ISCU/FeS Pathway

Background and Objective: Glucose fluctuation (GF) has been reported to induce renal injury and diabetic nephropathy (DN). However, the mechanism still remains ambiguous. Mitochondrial energy metabolism, especially aerobic glycolysis, has been a hotspot of DN research for decades. The activation of HIF-1α/miR210/ISCU/FeS axis has provided a new explanation for aerobic glycolysis. Our previous studies indicated quercetin as a potential therapeutic drug for DN. This study aims to evaluate levels of aerobic glycolysis and repressive effect of quercetin via HIF-1α/miR210/ISCU/FeS axis in a cell model of GF. Methods: The mouse glomerular mesangial cells (MCs) were exposed in high or oscillating glucose with or without quercetin treatment. Cell viability was measured by CCK8 assay. Aerobic glycolysis flux was evaluated by lactate acid, pH activity of PFK. Apoptosis level was confirmed by Annexin V-APC/7-AAD double staining and activity of caspase-3. TNF-α and IL-1β were used to evaluate inflammation levels. Results: GF deteriorated inflammation damage and apoptosis injury in MCs, while quercetin could alleviate this GF-triggered cytotoxicity. GF intensified aerobic glycolysis in MCs and quercetin could inhibit this intensification in a dose-dependent manner. Quercetin prevented activities of two FeS-dependent metabolic enzymes, aconitase, and complex I, under GF injury in MCs. The mRNA expression and protein contents of HIF-1α were increased after GF exposure, and these could be alleviated by quercetin treatment. Knockdown of ISCU by siRNA and Up-regulating of miR-210 by mimic could weaken the effects of quercetin that maintained protein levels of ISCU1/2, improved cell viability, relieved inflammation injury, decreased apoptosis, and reduced aerobic glycolysis switch in MCs. Conclusion: Quercetin antagonizes GF-induced renal injury by suppressing aerobic glycolysis via HIF-1α/miR-210/ISCU/FeS pathway in MCs cell model. Our findings contribute to a new insight into understanding the mechanism of GF-induced renal injury and protective effects of quercetin.

Non-Coding RNAs in Retinoic Acid as Differentiation and Disease Drivers

All-trans retinoic acid (RA) is the most active metabolite of vitamin A. Several studies have described a pivotal role for RA signalling in different biological processes such as cell growth and differentiation, embryonic development and organogenesis. Since RA signalling is highly dose-dependent, a fine-tuning regulatory mechanism is required. Thus, RA signalling deregulation has a major impact, both in development and disease, related in many cases to oncogenic processes. In this review, we focus on the impact of ncRNA post-transcriptional regulatory mechanisms, especially those of microRNAs and lncRNAs, in RA signalling pathways during differentiation and disease.

Loss of miR-23b/27b/24-1 Cluster Impairs Glucose Tolerance via Glycolysis Pathway in Mice

Alterations in miRNAs are associated with many metabolic disorders, such as type 2 diabetes (T2DM). The miR-23b/27b/24-1 cluster contains miR-23b, miR-27b, and miR-24-1, which are located within 881 bp on chromosome 9. Studies examining the roles of miR-23b, miR-27b, and miR-24-1 have demonstrated their multifaceted functions in variable metabolic disorders. However, their joint roles in metabolism in vivo remain elusive. To investigate this subject, we constructed miR-23b/27b/24-1 cluster knockout (KO) mice. Compared with wild-type (WT) mice, the KO mice exhibited impaired glucose tolerance, which was accompanied by a reduction in the respiratory exchange rate (RER). These alterations were more noticeable after a high-fat diet (HFD) induction. Hepatic metabolomic results showed decreased expression of reduced nicotinamide adenine dinucleotide (NADH), nicotinamide adenine dinucleotide (NAD), phosphoenolpyruvic acid (PEP), and phosphoric acid, which are involved in the glycolysis pathway. The transcriptomic results indicated that genes involved in glycolysis showed a downregulation trend. qPCR and Western blot revealed that pyruvate kinase (PKLR), the key rate-limiting enzyme in glycolysis, was significantly reduced after the deletion of the miR-23b/27b/24-1 cluster. Together, these observations suggest that the miR-23b/27b/24-1 cluster is involved in the regulation of glucose homeostasis via the glycolysis pathway.

Noncoding RNAs: the shot callers in tumor immune escape

Immunotherapy, designed to exploit the functions of the host immune system against tumors, has shown considerable potential against several malignancies. However, the utility of immunotherapy is heavily limited due to the low response rate and various side effects in the clinical setting. Immune escape of tumor cells may be a critical reason for such low response rates. Noncoding RNAs (ncRNAs) have been identified as key regulatory factors in tumors and the immune system. Consequently, ncRNAs show promise as targets to improve the efficacy of immunotherapy in tumors. However, the relationship between ncRNAs and tumor immune escape (TIE) has not yet been comprehensively summarized. In this review, we provide a detailed account of the current knowledge on ncRNAs associated with TIE and their potential roles in tumor growth and survival mechanisms. This review bridges the gap between ncRNAs and TIE and broadens our understanding of their relationship, providing new insights and strategies to improve immunotherapy response rates by specifically targeting the ncRNAs involved in TIE.

Retinoic acid and microRNA

Retinoic acid (RA), the biologically active metabolite of vitamin A, regulates a vast spectrum of biological processes, such as cell differentiation, proliferation, apoptosis, and morphogenesis. microRNAs (miRNAs) play a crucial role in regulating gene expression by binding to messenger RNA (mRNA) which leads to mRNA degradation and/or translational repression. Like RA, miRNAs regulate multiple biological processes, including proliferation, differentiation, apoptosis, neurogenesis, tumorigenesis, and immunity. In fact, RA regulates the expression of many miRNAs to exert its biological functions. miRNA and RA regulatory networks have been studied in recent years. In this manuscript, we summarize literature that highlights the impact of miRNAs in RA-regulated molecular networks included in the PubMed.

Non-coding RNAs: Key regulators of aerobic glycolysis in breast cancer

Although extensive research progress has been made in breast cancer in recent years, yet the morbidity and mortality rates of breast cancer are rising, making it the major disease that endangers women's health. Energy metabolism reprogramming is featured by a state termed "aerobic glycolysis" or the Warburg effect that glycolysis is preferred even under aerobic conditions in neoplastic diseases. Widely acknowledged as an emerging hallmark in cancers, this metabolic switch shows a sophisticated role in the pathogenesis of breast cancer. The regulating effect of non-coding RNAs (ncRNAs) composed of microRNAs, long non-coding RNAs and circular RNAs is closely related to the glycolysis in breast cancer. Therefore, understand the mechanisms of ncRNAs of aerobic glycolysis in breast cancer may provide new strategy for the disease.

MicroRNA and retinoic acid

BACKGROUND AND OBJECTIVE

Retinoic acid is a metabolite of vitamin A that is necessary to maintain health in human and most of the other vertebrates. MicroRNAs (miR or miRNAs) are small, non-coding RNA particles that diminish mRNA translation of various genes and so can regulate critical cell processes including cell death, proliferation, development, etc. The aim of this review is to study interrelations between retinoic acid with miRNAs.

METHODS

We reviewed and summarized all published articles in PubMed, Europe PMC, and Embase databases with any relationship between retinoic acid and miRNAs from Jun 2003 to Dec 2018 that includes 126 articles.

RESULTS

Results showed direct and indirect relationships between retinoic acid and miRNAs in various levels including effects of retinoic acid on expression of various miRNAs and miRNA-biogenesis enzymes, and effect of miRNAs on metabolism of retinoic acid.

DISCUTION AND CONCLUSION

This review indicates that retinoic acid has inter-correlations with various miRNA members and their metabolism in health and disease may require implications of the other.

The Estrogen-Induced miR-19 Downregulates Secretory Leucoprotease Inhibitor Expression in Monocytes

Compared to females, males are more susceptible to acute viral and other respiratory tract infections that display greater severity and higher mortality. In contrast, females tend to fare worse with chronic inflammatory diseases. Circulating 17β-estradiol (E2) is a female-specific factor that may influence the progression of human lung diseases. Here we hypothesize that E2 modulates the inflammatory response of monocytes through microRNA (miRNA)-based modulation of secretory leucoprotease inhibitor (SLPI), an antiprotease with immunomodulatory effects. Monocytic cells were treated ± E2, and differentially expressed miRNAs were identified using PCR profiling. Cells were transfected with miRNA mimics or antimiRs and SLPI mRNA and protein levels were quantified. Luciferase activity assay using wildtype and ΔmiR-19a/b-SLPI3'UTR reporter constructs and chromatin immunoprecipitation on E2-treated monocytes were performed. E2 downregulated SLPI and upregulated miR-19 expression in monocytes. Transfection with premiR-19b reduced SLPI mRNA and protein levels and this effect was abrogated using antimiRs against miR-19b. miR-19b directly binds the SLPI 3'UTR. The mechanism responsible for E2-mediated upregulation of miR-19 occurs via increased MIR17HG promoter activity mediated by c-MYC. Overall E2 decreases SLPI expression in human monocytic cells, via changes in miRNA expression and highlights the potential for estrogen to modulate the innate immune system.

Hypoxia- and MicroRNA-Induced Metabolic Reprogramming of Tumor-Initiating Cells

Colorectal cancer (CRC), the second most common cause of cancer mortality in the Western world, is a highly heterogeneous disease that is driven by a rare subpopulation of tumorigenic cells, known as cancer stem cells (CSCs) or tumor-initiating cells (TICs). Over the past few years, a plethora of different approaches, aimed at identifying and eradicating these self-renewing TICs, have been described. A focus on the metabolic and bioenergetic differences between TICs and less aggressive differentiated cancer cells has thereby emerged as a promising strategy to specifically target the tumorigenic cell compartment. Extrinsic factors, such as nutrient availability or tumor hypoxia, are known to influence the metabolic state of TICs. In this review, we aim to summarize the current knowledge on environmental stress factors and how they affect the metabolism of TICs, with a special focus on microRNA (miRNA)- and hypoxia-induced effects on colon TICs.

MicroRNAs as possible indicators of drug sensitivity in breast cancer cell lines

MicroRNAs (miRNAs) regulate gene expression post-transcriptionally. In this way they might influence whether a cell is sensitive or resistant to a certain drug. So far, only a limited number of relatively small scale studies comprising few cell lines and/or drugs have been performed. To obtain a broader view on miRNAs and their association with drug response, we investigated the expression levels of 411 miRNAs in relation to drug sensitivity in 36 breast cancer cell lines. For this purpose IC₅₀ values of a drug screen involving 34 drugs were associated with miRNA expression data of the same breast cancer cell lines. Since molecular subtype of the breast cancer cell lines is considered a confounding factor in drug association studies, multivariate analysis taking subtype into account was performed on significant miRNA-drug associations which retained 13 associations. These associations consisted of 11 different miRNAs and eight different drugs (among which Paclitaxel, Docetaxel and Veliparib). The taxanes, Paclitaxel and Docetaxel, were the only drugs having miRNAs in common: hsa-miR-187-5p and hsa-miR-106a-3p indicative of drug resistance while Paclitaxel sensitivity alone associated with hsa-miR-556-5p. Tivantinib was associated with hsa-let-7d-5p and hsa-miR-18a-5p for sensitivity and hsa-miR-637 for resistance. Drug sensitivity was associated with hsa-let-7a-5p for Bortezomib, hsa-miR-135a-3p for JNJ-707 and hsa-miR-185-3p for Panobinostat. Drug resistance was associated with hsa-miR-182-5p for Veliparib and hsa-miR-629-5p for Tipifarnib. Pathway analysis for significant miRNAs was performed to reveal biological roles, aiding to find a potential mechanistic link for the observed associations with drug response. By doing so hsa-miR-187-5p was linked to the cell cycle G2-M checkpoint in line with this checkpoint being the target of taxanes. In conclusion, our study shows that miRNAs could potentially serve as biomarkers for intrinsic drug resistance and that pathway analyses can provide additional information in this context.

Micromanaging aerobic respiration and glycolysis in cancer cells

BACKGROUND

Cancer cells possess a common metabolic phenotype, rewiring their metabolic pathways from mitochondrial oxidative phosphorylation to aerobic glycolysis and anabolic circuits, to support the energetic and biosynthetic requirements of continuous proliferation and migration. While, over the past decade, molecular and cellular studies have clearly highlighted the association of oncogenes and tumor suppressors with cancer-associated glycolysis, more recent attention has focused on the role of microRNAs (miRNAs) in mediating this metabolic shift. Accumulating studies have connected aberrant expression of miRNAs with direct and indirect regulation of aerobic glycolysis and associated pathways.

SCOPE OF REVIEW

This review discusses the underlying mechanisms of metabolic reprogramming in cancer cells and provides arguments that the earlier paradigm of cancer glycolysis needs to be updated to a broader concept, which involves interconnecting biological pathways that include miRNA-mediated regulation of metabolism. For these reasons and in light of recent knowledge, we illustrate the relationships between metabolic pathways in cancer cells. We further summarize our current understanding of the interplay between miRNAs and these metabolic pathways. This review aims to highlight important metabolism-associated molecular components in the hunt for selective preventive and therapeutic treatments.

MAJOR CONCLUSIONS

Metabolism in cancer cells is influenced by driver mutations but is also regulated by posttranscriptional gene silencing. Understanding the nuanced regulation of gene expression in these cells and distinguishing rapid cellular responses from chronic adaptive mechanisms provides a basis for rational drug design and novel therapeutic strategies.

In silico drug repositioning based on drug-miRNA associations

Drug repositioning has become a prevailing tactic as this strategy is efficient, economical and low risk for drug discovery. Meanwhile, recent studies have confirmed that small-molecule drugs can modulate the expression of disease-related miRNAs, which indicates that miRNAs are promising therapeutic targets for complex diseases. In this study, we put forward and verified the hypothesis that drugs with similar miRNA profiles may share similar therapeutic properties. Furthermore, a comprehensive drug–drug interaction network was constructed based on curated drug-miRNA associations. Through random network comparison, topological structure analysis and network module extraction, we found that the closely linked drugs in the network tend to treat the same diseases. Additionally, the curated drug–disease relationships (from the CTD) and random walk with restarts algorithm were utilized on the drug–drug interaction network to identify the potential drugs for a given disease. Both internal validation (leave-one-out cross-validation) and external validation (independent drug–disease data set from the ChEMBL) demonstrated the effectiveness of the proposed approach. Finally, by integrating drug-miRNA and miRNA-disease information, we also explain the modes of action of drugs in the view of miRNA regulation. In summary, our work could determine novel and credible drug indications and offer novel insights and valuable perspectives for drug repositioning.

microRNA-23a in Human Cancer: Its Roles, Mechanisms and Therapeutic Relevance

microRNA-23a (miR-23a) is one of the most extensively studied miRNAs in different types of human cancer, and plays various roles in the initiation, progression, and treatment of tumors. Here, we comprehensively summarize and discuss the recent findings about the role of miR-23a in cancer. The differential expression of tissue miR-23a was reported, potentially indicating cancer stages, angiogenesis, and metastasis. miR-23a in human biofluid, such as plasma and salivary fluid, may be a sensitive and specific marker for early diagnosis of cancer. Tissue and circulating miR-23a serves as a prognostic factor for cancer patient survival, as well as a predictive factor for response to anti-tumor treatment. The direct and indirect regulation of miR-23a on multiple gene expression and signaling transduction mediates carcinogenesis, tumor proliferation, survival, cell migration and invasion, as well as the response to anti-tumor treatment. Tumor cell-derived miR-23a regulates the microenvironment of human cancer through manipulating both immune function and tumor vascular development. Several transcriptional and epigenetic factors may contribute to the dysregulation of miR-23a in cancer. This evidence highlights the essential role of miR-23a in the application of cancer diagnosis, prognosis, and treatment.

Spatiotemporal Analysis of a Glycolytic Activity Gradient Linked to Mouse Embryo Mesoderm Development

How metabolism is rewired during embryonic development is still largely unknown, as it remains a major technical challenge to resolve metabolic activities or metabolite levels with spatiotemporal resolution. Here, we investigated metabolic changes during development of organogenesis-stage mouse embryos, focusing on the presomitic mesoderm (PSM). We measured glycolytic labeling kinetics from ¹³C-glucose tracing experiments and detected elevated glycolysis in the posterior, more undifferentiated PSM. We found evidence that the spatial metabolic differences are functionally relevant during PSM development. To enable real-time quantification of a glycolytic metabolite with spatiotemporal resolution, we generated a pyruvate FRET-sensor reporter mouse line. We revealed dynamic changes in cytosolic pyruvate levels as cells transit toward a more anterior PSM state. Combined, our approach identifies a gradient of glycolytic activity across the PSM, and we provide evidence that these spatiotemporal metabolic changes are intrinsically linked to PSM development and differentiation.

•

Identification of glycolytic activity gradient in mouse presomitic mesoderm

•

Development of a pyruvate FRET-reporter mouse model

•

Real-time imaging reveals pyruvate gradient dynamics

•

Metabolic state is linked to presomitic mesoderm cell differentiation

Expression and regulation of Angiopoietins and their receptor Tie-2 in sika deer antler

The cartilage vascularization and chondrocyte survival are essential for endochondral ossification which occurs in the process of antler growth. Angiopoietins (Ang) is a family of major angiogenic growth factors and involved in regulating the vascularization. However, the expression and regulation of Angs in the antler are still unknown. The aim of this study is to localize the expression of Ang-1, Ang-2 and their receptor Tie-2 in sika deer antler using in situ hybridization and focused on analyzing the regulation of testosterone, estrogen, all-trans-retinoic acid (ATRA) and 9cRA on their expression in antler chondrocytes. The results showed that Ang-1, Ang-2 and Tie-2 were highly expressed in antler chondrocytes. Administration of testosterone to antler chondrocytes led to a notable increase in the expression of Ang-1 and Tie-2, and a reduction in the expression of Ang-2. The similar result was also observed after estrogen treatment. In contrast, ATRA and 9cRA could inhibit the expression of Ang-1 in antler chondrocytes and heighten the expression of Ang-2. Simultaneously, ATRA could downregulate the expression of Tie-2 in antler chondrocytes at 12 and 24 h, while 9cRA upregulate the expression of Tie-2 at 3 and 6 h. Collectively, Ang-1, Ang-2 and Tie-2 are expressed in antler chondrocytes and their expression can be affected by testosterone, estrogen, ATRA and 9cRA.

Long-term exposure of MCF-7 breast cancer cells to ethanol stimulates oncogenic features

Alcohol consumption is a risk factor for breast cancer. Little is known regarding the mechanism, although it is assumed that acetaldehyde or estrogen mediated pathways play a role. We previously showed that long-term exposure to 2.5 mM ethanol (blood alcohol ~0.012%) of MCF-12A, a human normal epithelial breast cell line, induced epithelial mesenchymal transition (EMT) and oncogenic transformation. In this study, we investigated in the human breast cancer cell line MCF-7, whether a similar exposure to ethanol at concentrations ranging up to peak blood levels in heavy drinkers would increase malignant progression. Short-term (1-week) incubation to ethanol at as low as 1-5 mM (corresponding to blood alcohol concentration of ~0.0048-0.024%) upregulated the stem cell related proteins Oct4 and Nanog, but they were reduced after exposure at 25 mM. Long-term (4-week) exposure to 25 mM ethanol upregulated the Oct4 and Nanog proteins, as well as the malignancy marker Ceacam6. DNA microarray analysis in cells exposed for 1 week showed upregulated expression of metallothionein genes, particularly MT1X. Long-term exposure upregulated expression of some malignancy related genes (STEAP4, SERPINA3, SAMD9, GDF15, KRT15, ITGB6, TP63, and PGR, as well as the CEACAM, interferon related, and HLA gene families). Some of these findings were validated by RT-PCR. A similar treatment also modulated numerous microRNAs (miRs) including one regulator of Oct4 as well as miRs involved in oncogenesis and/or malignancy, with only a few estrogen-induced miRs. Long-term 25 mM ethanol also induced a 5.6-fold upregulation of anchorage-independent growth, an indicator of malignant-like features. Exposure to acetaldehyde resulted in little or no effect comparable to that of ethanol. The previously shown alcohol induction of oncogenic transformation of normal breast cells is now complemented by the current results suggesting alcohol's potential involvement in malignant progression of breast cancer.

Clinical effects of miR-101 on prognosis of hepatocellular carcinoma and carcinogenic mechanism of anti-miR-101

The aim of this study was to verify whether anti-miR-101 participates in the treatment of hepatocellular carcinoma (HCC) as a small-molecule antitumor agent, and to explore the effect on phosphatase and tensin homolog deleted on chromosome 10 (PTEN). Patients who received consecutive hepatectomies were followed-up, and miR-101 expressions in their tumor and paracancerous tissues were detected. Correlation between miR-101 expression and clinical pathological factors and prognosis was studied. High‑throughput sequencing was used to detect the genetic and microRNA (miRNA) levels of tumor tissues. Expression of anti-miR-101 in different HCC cell lines was determined, and those of desired genes and proteins were detected by qRT-PCR and western blotting to obtain the target gene. miR-101 was significantly upregulated in HCC patients compared with that in paracancerous tissues. High miR-101 expression, vascular invasion, tumor size ≥7 cm and late pathological stage were the risk factors of recurrence-free survival rate. High miR-101 expression was the independent prognostic factor of total and recurrence-free survival rates. CXCL12, IL6R, FOXO3 and PTEN were screened as desired genes, and only PTEN was expressed significantly differently in three cell lines. miR-101 could bind 3'-UTR of WT-PTEN with reduced fluorescent intensity, suggesting that PTEN was the target gene. SMMC-7721, HepG2 and Huh7 were eligible cell lines for miR-101 studies. miR-101 was an applicable molecular marker of HCC. Anti-miR-101 regulated the transcription of PTEN and may promote cell proliferation, differentiation and apoptosis by regulating downstream genes with PTEN. The regulatory effects of anti-miR-101 on PTEN provide valuable evidence for finding novel miRNA drugs.

MicroRNA networks regulated by all-trans retinoic acid and Lapatinib control the growth, survival and motility of breast cancer cells

SKBR3-cells, characterized by ERBB2/RARA co-amplification, represent a subgroup of HER2⁺ breast-cancers sensitive to all-trans retinoic acid (ATRA) and Lapatinib. In this model, the two agents alone or in combination modulate the expression of 174 microRNAs (miRs). These miRs and predicted target-transcripts are organized in four interconnected modules (Module-1 to -4). Module-1 and Module-3 consist of ATRA/Lapatinib up-regulated and potentially anti-oncogenic miRs, while Module-2 contains ATRA/Lapatinib down-regulated and potentially pro-oncogenic miRs. Consistent with this, the expression levels of Module-1/-3 and Module-2 miRs are higher and lower, respectively, in normal mammary tissues relative to ductal-carcinoma-in-situ, invasive-ductal-carcinoma and metastases. This indicates associations between tumor-progression and the expression profiles of Module-1 to -3 miRs. Similar associations are observed with tumor proliferation-scores, staging, size and overall-survival using TCGA (The Cancer Genome Atlas) data. Forced expression of Module-1 miRs, (miR-29a-3p; miR-874-3p) inhibit SKBR3-cell growth and Module-3 miRs (miR-575; miR-1225-5p) reduce growth and motility. Module-2 miRs (miR-125a; miR-193; miR-210) increase SKBR3 cell growth, survival and motility. Some of these effects are of general significance, being replicated in other breast cancer cell lines representing the heterogeneity of this disease. Finally, our study demonstrates that HIPK2-kinase and the PLCXD1-phospholipase-C are novel targets of miR-193a-5p/miR-210-3p and miR-575/miR-1225-5p, respectively.

miRNAs regulated by estrogens, tamoxifen, and endocrine disruptors and their downstream gene targets

MicroRNAs (miRNAs) are short (22 nucleotides), single-stranded, non-coding RNAs that form complimentary base-pairs with the 3' untranslated region of target mRNAs within the RNA-induced silencing complex (RISC) and block translation and/or stimulate mRNA transcript degradation. The non-coding miRBase (release 21, June 2014) reports that human genome contains ∼ 2588 mature miRNAs which regulate ∼ 60% of human protein-coding mRNAs. Dysregulation of miRNA expression has been implicated in estrogen-related diseases including breast cancer and endometrial cancer. The mechanism for estrogen regulation of miRNA expression and the role of estrogen-regulated miRNAs in normal homeostasis, reproduction, lactation, and in cancer is an area of great research and clinical interest. Estrogens regulate miRNA transcription through estrogen receptors α and β in a tissue-specific and cell-dependent manner. This review focuses primarily on the regulation of miRNA expression by ligand-activated ERs and their bona fide gene targets and includes miRNA regulation by tamoxifen and endocrine disrupting chemicals (EDCs) in breast cancer and cell lines.

MicroRNAs in lupus

Systemic lupus erythematosus is a prototypic autoimmune disease characterized by the production of an array of pathogenic autoantibodies, including high-affinity anti-dsDNA IgG antibodies, which play an important role in disease development and progression. Lupus preferentially affects women during their reproductive years. The pathogenesis of lupus is contributed by both genetic factors and epigenetic modifications that arise from exposure to the environment. Epigenetic marks, including DNA methylation, histone post-translational modifications and microRNAs (miRNAs), interact with genetic programs to regulate immune responses. Epigenetic modifications influence gene expression and modulate B cell functions, such as class-switch DNA recombination, somatic hypermutation and plasma cell differentiation, thereby informing the antibody response. Epigenetic dysregulation can result in aberrant antibody responses to exogenous antigens or self-antigens, such as chromatin, histones and dsDNA in lupus. miRNAs play key roles in the post-transcriptional regulation of most gene-regulatory pathways and regulate both the innate and adaptive immune responses. In mice, dysregulation of miRNAs leads to aberrant immune responses and development of systemic autoimmunity. Altered miRNA expression has been reported in human autoimmune diseases, including lupus. The dysregulation of miRNAs in lupus could be the result of multiple environmental factors, such as sex hormones and viral or bacterial infection. Modulation of miRNA is a potential therapeutic strategy for lupus.

Relationship between Carotenoids, Retinol, and Estradiol Levels in Older Women

BACKGROUND

In vitro evidence suggests anti-estrogenic properties for retinol and carotenoids, supporting a chemo-preventive role of these phytochemicals in estrogen-dependent cancers. During aging there are significant reductions in retinol and carotenoid concentrations, whereas estradiol levels decline during menopause and progressively increase from the age of 65. We aimed to investigate the hypothesis of a potential relationship between circulating levels of retinol, carotenoids, and estradiol (E2) in a cohort of late post-menopausal women.

METHODS

We examined 512 women ≥ 65 years from the InCHIANTI study. Retinol, α-caroten, β-caroten, β-criptoxantin, lutein, zeaxanthin, and lycopene levels were assayed at enrollment (1998-2000) by High-Performance Liquid Chromatography. Estradiol and testosterone (T) levels were assessed by Radioimmunometry (RIA) and testosterone-to-estradiol ratio (T/E2), as a proxy of aromatase activity, was also calculated. General linear models adjusted for age (Model 1) and further adjusted for other confounders including Body Mass Index (BMI) BMI, smoking, intake of energy, lipids, and vitamin A; C-Reactive Protein, insulin, total cholesterol, liver function, and testosterone (Model 2) were used to investigate the relationship between retinol, carotenoids, and E2 levels. To address the independent relationship between carotenoids and E2 levels, factors significantly associated with E2 in Model 2 were also included in a fully adjusted Model 3.

RESULTS

After adjustment for age, α-carotene (β ± SE = -0.01 ± 0.004, p = 0.02) and β-carotene (β ± SE = -0.07 ± 0.02, p = 0.0007) were significantly and inversely associated with E2 levels. α-Carotene was also significantly and positively associated with T/E2 ratio (β ± SE = 0.07 ± 0.03, p = 0.01). After adjustment for other confounders (Model 2), the inverse relationship between α-carotene (β ± SE = -1.59 ± 0.61, p = 0.01), β-carotene (β ± SE = -0.29 ± 0.08, p = 0.0009), and E2 persisted whereas the relationship between α-carotene and T/E2 ratio was attenuated (β ± SE = 0.22 ± 0.12, p = 0.07). In a fully adjusted model (Model 3), only β-carotene (β ± SE = -0.05 ± 0.02, p = 0.03) was significantly and inversely associated with E2 levels independent of α-carotene. No association was found between retinol, total non-pro-vitamin A carotenoids, lutein, zeaxanthin, and lycopene, and E2 levels.

CONCLUSIONS

In older women, β-carotene levels are independently and inversely associated with E2.

Breast tissue-based microRNA panel highlights microRNA-23a and selected target genes as putative biomarkers for breast cancer

We explored the differential expression of breast tissue-based panel of microRNAs (miRNAs) and their potential application as prognostic markers of breast cancer (BC). This study was divided into the following phases: (1) A panel of 6 BC characteristic miRNAs, which were retrieved based on the microarray signature profiling (released by miRWalk), was explored using SYBR Green-based polymerase chain reaction (PCR) array in 16 cancerous and 16 noncancerous breast tissue; (2) pathway enrichment analysis of the key miRNA target genes; (3) marker choice and validation by real-time PCR in a larger set of 76 patients with BC, 36 benign breast conditions, and 36 healthy volunteers; (4) validation of miRNA (miR)-23a target genes (forkhead box m [FOXM1] and histidine-rich glycoprotein [HRG]) by conventional reverse transcriptase (RT)-PCR; and (5) the prognostic significance of the investigated parameters in the BC validation group was explored. In PCR array-based miRNA expression analysis, 4 miRNAs were found to be altered more than twice (miR-96, miR-29c, miR-221, and miR-23a). Bioinformatic analysis of the target genes revealed enrichment for special biological process categories, that is, cell cycle, angiogenesis, apoptosis, cell proliferation, and cell adhesion. miR-23a, HRG messenger RNA, and FOX messenger RNA were positive in BC by 82.9%, 72.4%, and 71.1%, respectively. The overall concordance rates between miR-23a with HRG and FOXM1 tissue RNAs were 91% and 79%, respectively. The median follow-up period was 49 months. mi-23a and HRG RNA were significant independent prognostic markers in relapse-free survival. miR-23a may have an oncogenic function and enhance BC progression by directly activating FOXM1 and HRG at RNA level.

microRNAs and Personalized Medicine: Evaluating Their Potential as Cancer Biomarkers

microRNA deregulations are often, if not invariably, associated with human malignancies, including cancers. Though most of these deregulations may not be functionally implicated in tumorigenesis, the fact that microRNA expression can be monitored in a variety of human specimens, including biological fluids, supports studies aimed at characterizing microRNA signatures able to detect various cancers (diagnosis), predict their outcome (prognosis), monitor their treatment (theranosis), and adapt therapy to a patient (precision medicine). Here, we review and discuss pros and cons of microRNA-based approaches that can support their exploitation as cancer biomarkers.

MiR-23a facilitates the replication of HSV-1 through the suppression of interferon regulatory factor 1

MicroRNAs (miRNAs) are small, non-coding RNAs that negatively regulate gene expression. It has been reported that miRNAs are involved in host-virus interaction, but evidence that cellular miRNAs promote virus replication has been limited. Here, we found that miR-23a promoted the replication of human herpes simplex virus type 1 (HSV-1) in HeLa cells, as demonstrated by a plaque-formation assay and quantitative real-time PCR. Furthermore, interferon regulatory factor 1 (IRF1), an innate antiviral molecule, is targeted by miR-23a to facilitate viral replication. MiR-23a binds to the 3′UTR of IRF1 and down-regulates its expression. Suppression of IRF1 expression reduced RSAD2 gene expression, augmenting HSV-1 replication. Ectopic expression of IRF1 abrogated the promotion of HSV-1 replication induced by miR-23a. Notably, IRF1 contributes to innate antiviral immunity by binding to IRF-response elements to regulate the expression of interferon-stimulated genes (ISGs) and apoptosis, revealing a complex interaction between miR-23a and HSV-1. MiR-23a thus contributes to HSV-1 replication through the regulation of the IRF1-mediated antiviral signal pathway, which suggests that miR-23a may represent a promising target for antiviral treatments.

The potential of microRNAs in personalized medicine against cancers

MicroRNAs orchestrate the expression of the genome and impact many, if not all, cellular processes. Their deregulation is thus often causative of human malignancies, including cancers. Numerous studies have implicated microRNAs in the different steps of tumorigenesis including initiation, progression, metastasis, and resistance to chemo/radiotherapies. Thus, microRNAs constitute appealing targets for novel anticancer therapeutic strategies aimed at restoring their expression or function. As microRNAs are present in a variety of human cancer types, microRNA profiles can be used as tumor-specific signatures to detect various cancers (diagnosis), to predict their outcome (prognosis), and to monitor their treatment (theranosis). In this review, we present the different aspects of microRNA biology that make them remarkable molecules in the emerging field of personalized medicine against cancers and provide several examples of their industrial exploitation.

Interplay between estrogen and retinoid signaling in breast cancer--current and future perspectives

All-trans-retinoic acid (RA) is a promising agent for breast cancer treatment, but it induces several adverse effects and the few clinical trials performed up to now in breast cancer patients have provided disappointing results. The combination of RA and antiestrogenic compounds, such as tamoxifen, synergistically decreases the proliferation of breast cancer cells and an interplay between retinoid and estrogen signaling has begun to be unraveled, turning these combinations into an appealing strategy for breast cancer treatment. This review focus on the current knowledge regarding the interplay between retinoid and estrogen signaling in breast cancer and the combinations of RA with antiestrogens, aiming their future utilization in cancer therapy.

Cancer stem cell theory and the warburg effect, two sides of the same coin?

Over the last 100 years, many studies have been performed to determine the biochemical and histopathological phenomena that mark the origin of neoplasms. At the end of the last century, the leading paradigm, which is currently well rooted, considered the origin of neoplasms to be a set of genetic and/or epigenetic mutations, stochastic and independent in a single cell, or rather, a stochastic monoclonal pattern. However, in the last 20 years, two important areas of research have underlined numerous limitations and incongruities of this pattern, the hypothesis of the so-called cancer stem cell theory and a revaluation of several alterations in metabolic networks that are typical of the neoplastic cell, the so-called Warburg effect. Even if this specific “metabolic sign” has been known for more than 85 years, only in the last few years has it been given more attention; therefore, the so-called Warburg hypothesis has been used in multiple and independent surveys. Based on an accurate analysis of a series of considerations and of biophysical thermodynamic events in the literature, we will demonstrate a homogeneous pattern of the cancer stem cell theory, of the Warburg hypothesis and of the stochastic monoclonal pattern; this pattern could contribute considerably as the first basis of the development of a new uniform theory on the origin of neoplasms. Thus, a new possible epistemological paradigm is represented; this paradigm considers the Warburg effect as a specific “metabolic sign” reflecting the stem origin of the neoplastic cell, where, in this specific metabolic order, an essential reason for the genetic instability that is intrinsic to the neoplastic cell is defined.

In silico analysis of pathways affected by differentially expressed microRNA in adrenocortical tumors

BACKGROUND

MicroRNA are involved in the pathogenesis of several tumors, and several studies have been performed on the microRNA profile of adrenocortical tumors to date. The pathways affected by these microRNA, however, have not been analyzed yet by a systematic approach.

AIM

To perform an in silico bioinformatics analysis of microRNA commonly altered in at least two studies and to decipher the pathways affected by microRNA in adrenocortical tumors.

METHODS

Datasets on microRNA and mRNA expression have been retrieved from 5 and 3 studies, respectively. MicroRNA mRNA targets have been identified by our tissue specific target prediction pipeline, and mRNA have been subjected to Ingenuity Pathway Analysis.

RESULTS

Thirty- nine microRNA were identified as commonly altered in two studies. Altogether 49,817 mRNA targets have been found for these microRNA. One-hundred and seventy-eight significant pathways associating with these have been identified and were found in all studies. We have selected 12 pathways involving retinoic acid signaling (lipopolysaccharide/ interleukin-1 mediated inhibition of retinoic X receptor (RXR) function, peroxisome proliferator-activated receptor (PPAR)α/RXRα activation, retinoic A receptor activation and PPAR signaling pathways) and cell cycle alterations (aryl hydrocarbon receptor signaling, growth arrest and DNA damage-inducible 45 signaling, integrin signaling, G2/M DNA damage checkpoint regulation, cyclins and cell cycle regulation and cell cycle control of chromosomal replication pathways) as these have been also established in our previous study on the functional genomics meta-analysis of adrenocortical tumors. Several microRNA have been identified that could affect these pathways.

CONCLUSIONS

MicroRNA might affect several pathogenic pathways in adrenocortical tumors. Validation studies are required to confirm the biological relevance of these findings.

Epigenetic regulation of hepatocellular carcinoma in non-alcoholic fatty liver disease

Emerging evidence that epigenetics converts alterations in nutrient and metabolism into heritable pattern of gene expression has profound implications in understanding human physiology and diseases. Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome including obesity and diabetes which elevate the risk of hepatocellular carcinoma (HCC) especially in male. This review focuses on the molecular connections between metabolic dysfunction and aberrant epigenetic alterations in the development of HCC in NAFLD. The metabolites derived from excessive insulin, glucose and lipid may perturb epigenetic gene regulation through DNA methylation, histone modifications, and RNA interference, leading to activation of pro-inflammatory signaling and deregulation of metabolic pathways. The interplay and crosstalk of chromatin-modifying enzymes, microRNAs, signaling pathways and the downstream transcription factors result in epigenomic reprogramming that drives hepatocellular transformation. The interactions between sex hormone pathways and the epigenetic machineries that influence chromatin states in NAFLD provide potential molecular mechanisms of gender disparity in HCC. A deeper understanding of these connections and comprehensive molecular catalog of hepatocarcinogenesis may shed light in the identification of druggable epigenetic targets for the prevention and treatment of HCC in obese or diabetic patients.