Extracellular Vesicles and Vascular Inflammation.

Vascular inflammation is the most common pathological feature in the pathogenesis of human disease. It is a complex immune process involved with many different types of cells including platelet, monocytes, macrophages, endothelial cells, and others. It is widely accepted that both innate and adaptive immune responses are important for the initiation and progression of vascular inflammation. The cell-cell interaction constitutes an important aspect of those immune responses in the vascular inflammation. Extracellular vesicles (EVs) are nanometer-sized double-layer lipid membrane vesicles released from most types of cells. They have been proved to play critical roles in intercellular communication in the occurrence and development of multisystem diseases. With the advancement of basal medical science, the biological roles of EVs in vascular inflammation have been clearer today. In this chapter, we will summarize the advance progress of extracellular vesicles in regulating vascular inflammation and its potential application in the clinical.

Lymphatic endothelial sphingosine 1-phosphate receptor 1 enhances macrophage clearance via lymphatic system following myocardial infarction.

Lymphatic endothelial cell homeostasis plays important roles in normal physiological cardiac functions, and its dysfunction significantly influences pathological cardiac remodeling after myocardial infarction (MI). Our results revealed that sphingosine 1-phosphate receptor 1 (S1pr1) expression in cardiac lymphatic endothelial cells (LECs) was sharply changed after MI. It has been shown that S1pr1 tightly controlled LEC functions and homeostasis. We thus hypothesized that lymphatic endothelial S1pr1 might be involved in post-MI cardiac remodeling. We generated LEC-conditional S1pr1 transgenic mice, in which S1pr1 expression was reduced in cardiac LECs. We performed the left anterior descending coronary artery (LAD) ligation operation to induce MI in these mice. Cardiac functions and remodeling were examined by echocardiography analysis and serial histological analysis. Meanwhile, we performed adoptive cell transfer experiments to monitor macrophage trafficking in post-MI myocardium and their draining lymphatic system. Furthermore, in vitro cell culture experiments and mechanism studies were undertaken to uncover the molecular mechanism by which LEC-S1pr1 regulated cardiac inflammation and remodeling after MI. Our results showed that S1pr1 expression significantly decreased in cardiac LECs after MI. Our in vivo experiments showed that the reduced expression of LEC-S1pr1 deteriorated cardiac function and worsened pathological cardiac remodeling after MI. Our further results demonstrated that the reduced expression of LEC-S1pr1 did not influence macrophage infiltration in an early inflammatory phase of MI, but significantly affected macrophages clearance in the later phase of MI via afferent cardiac lymphatics, and thus influenced inflammatory responses and cardiac outcome after MI. Further study showed that S1P/S1pr1 activated ERK signaling pathway and enhanced CCL2 expression, which promoted macrophage trafficking in a paracrine manner. This study reveals that cardiac lymphatic endothelial cells tightly control macrophage trafficking via lymphatic vessels in injured hearts via S1P/S1pr1/ERK/CCL2 pathway and thus regulate post-MI immune modulation and heart repair. This study highlights the importance of cardiac lymphatic vessel system in orchestrating post-MI immune responses and cardiac remodeling by regulating macrophage transit in injured hearts. Our finding implies that a feasible modulation of S1pr1 signaling in LECs might provide a promising target to resolve excessive inflammation and to ameliorate adverse cardiac remodeling after MI.

Association Between the Aldehyde Dehydrogenase-2 rs671 G>A Polymorphism and Head and Neck Cancer Susceptibility: A Meta-Analysis in East Asians.

BACKGROUND: Aldehyde dehydrogenase-2 (ALDH2) plays an important role in the alcohol detoxification and acetaldehyde metabolism. Published studies have demonstrated some inconsistent associations between ALDH2 rs671 G>A polymorphism and head and neck cancer (HNC) risk. METHODS: A meta-analysis was performed to provide pooled data on the association between the ALDH2 rs671 G>A polymorphism and HNC risk. Electronic databases were searched to identify relevant studies. Odds ratios and 95% confidence intervals (CIs) were used to examine the pooled effect size of each genetic model. In addition, heterogeneity test, accumulative analysis, sensitivity analysis, and publication bias were conducted to test the statistical power. RESULTS: Thirteen publications (14 independent case-control studies) involving 10,939 subjects were selected. The stratified analysis indicated that both light/moderated drinking (e.g., GA vs. GG: OR = 1.47, 95% CI = 1.16 to 1.86, p < 0.01, I2  = 81.1%) and heavy drinking would increase HNC risk with rs671 G>A mutation (e.g., GA vs. GG: OR = 2.30, 95% CI = 1.11 to 4.77, p = 0.03, I2  = 81.9%). CONCLUSIONS: In summary, this meta-analysis suggested that the ALDH2 rs671 G>A polymorphism may play an important synergistic effect in the pathogenesis of HNC development in East Asians.

miR-301a-PTEN-AKT Signaling Induces Cardiomyocyte Proliferation and Promotes Cardiac Repair Post-MI.

Adult hearts are hard to recover after cardiac injury due to the limited proliferative ability of cardiomyocytes. Emerging evidence indicates the induction of cell cycle reentry of cardiomyocytes by special treatment or stimulation, which offers adult heart regenerative potential. Herein, a microRNA (miRNA) screening in cardiomyocytes identified miR-301a enriched specially in the neonatal cardiomyocytes from rats and mice. Overexpression of miR-301a in primary neonatal cardiomyocytes and H9C2 cells induced G1/S transition of the cell cycle, promoted cellular proliferation, and protected cardiomyocytes against hypoxia-induced apoptosis. Adeno-associated virus (AAV)9-mediated cardiac delivery of miR-301a to the mice model with myocardial infarction (MI) dramatically promoted cardiac repair post-MI in vivo. Phosphatase and tensin homolog (PTEN)/phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway was confirmed to mediate miR-301a-induced cell proliferation in cardiomyocytes. Loss of function of PTEN mimicked the miR-301a-induced phenotype, while gain of function of PTEN attenuated the miR-301a-induced cell proliferation in cardiomyocytes. Application of RG7440, a small molecule inhibitor of AKT, blocked the function of miR-301a in cardiomyocytes. The current study revealed a miRNA signaling in inducing the cell cycle reentry of cardiomyocytes in the injured heart, and it demonstrated the miR-301a/PTEN/AKT signaling as a potential therapeutic target to reconstitute lost cardiomyocytes in mammals.

Exosomes from SIRT1-Overexpressing ADSCs Restore Cardiac Function by Improving Angiogenic Function of EPCs.

Acute myocardial infarction (AMI) is one of the leading causes of mortality in cardiovascular diseases. The aim of this study was to investigate whether exosomes from Sirtuin 1 (SIRT1)-overexpressing adipose-derived stem cells (ADSCs) had a protective effect on AMI. The expression of C-X-C chemokine receptor type 7 (CXCR7) was significantly downregulated in peripheral blood endothelial progenitor cells (EPCs) from AMI patients (AMI-EPCs) compared with that in healthy donors, which coincided with impaired tube formation. The exosomes from SIRT1 overexpression in ADSCs (ADSCs-SIRT1-Exos) increased the expression of C-X-C motif chemokine 12 (CXCL12) and nuclear factor E2 related factor 2 (Nrf2) in AMI-EPCs, which promoted migration and tube formation of AMI-EPCs, and overexpression of CXCR7 helped AMI-EPCs to restore the function of cell migration and tube formation. Moreover, CXCR7 was downregulated in the myocardium of AMI mice, and knockout of CXCR7 exacerbated AMI-induced impairment of cardiovascular function. Injection of ADSCs-SIRT1-Exos increased the survival and promoted the recovery of myocardial function with reduced infarct size and post-AMI left ventricular remodeling, induced vasculogenesis, and decreased AMI-induced myocardial inflammation. These findings showed that ADSCs-SIRT1-Exos may recruit EPCs to the repair area and that this recruitment may be mediated by Nrf2/CXCL12/CXCR7 signaling.

Network pharmacology suggests biochemical rationale for treating COVID-19 symptoms with a Traditional Chinese Medicine.

Chinese herbal formulas including the lung-cleaning and toxicity-excluding (LCTE) soup have played an important role in treating the ongoing COVID-19 pandemic (caused by SARS-CoV-2) in China. Applying LCTE outside of China may prove challenging due to the unfamiliar rationale behind its application in terms of Traditional Chinese Medicine. To overcome this barrier, a biochemical understanding of the clinical effects of LCTE is needed. Here, we explore the chemical compounds present in the reported LCTE ingredients and the proteins targeted by these compounds via a network pharmacology analysis. Our results indicate that LCTE contains compounds with the potential to directly inhibit SARS-CoV-2 and inflammation, and that the compound targets proteins highly related to COVID-19's main symptoms. We predict the general effect of LCTE is to affect the pathways involved in viral and other microbial infections, inflammation/cytokine response, and lung diseases. Our work provides a biochemical basis for using LCTE to treat COVID-19 and its main symptoms.

lncRNA-NRF is a Potential Biomarker of Heart Failure After Acute Myocardial Infarction.

Long non-coding RNAs (lncRNAs) are a new focus in cardiovascular diseases. The necrosis-related factor (NRF) is a newly discovered lncRNA, which is increased in myocardial injury. We investigated the role of lncRNA-NRF in heart failure (HF) after acute myocardial infarction (AMI) to find a biomarker for early HF detection. This was a cross-sectional study of 76 AMI patients with HF and 58 AMI patients without HF. lncRNA-NRF was shown to be increased in AMI patients with HF compared with AMI patients without HF and had predictive value for diagnosis of HF. It had a high diagnostic value for HF (AUC, 0.975), while the AUC for N-terminal pro-brain natriuretic peptide was 0.720. Our findings suggest that lncRNA-NRF may represent a marker of risk for development of HF post-AMI.

In silico screening of Chinese herbal medicines with the potential to directly inhibit 2019 novel coronavirus.

OBJECTIVE: In this study we execute a rational screen to identify Chinese medical herbs that are commonly used in treating viral respiratory infections and also contain compounds that might directly inhibit 2019 novel coronavirus (2019-nCoV), an ongoing novel coronavirus that causes pneumonia. METHODS: There were two main steps in the screening process. In the first step we conducted a literature search for natural compounds that had been biologically confirmed as against sever acute respiratory syndrome coronavirus or Middle East respiratory syndrome coronavirus. Resulting compounds were cross-checked for listing in the Traditional Chinese Medicine Systems Pharmacology Database. Compounds meeting both requirements were subjected to absorption, distribution, metabolism and excretion (ADME) evaluation to verify that oral administration would be effective. Next, a docking analysis was used to test whether the compound had the potential for direct 2019-nCoV protein interaction. In the second step we searched Chinese herbal databases to identify plants containing the selected compounds. Plants containing 2 or more of the compounds identified in our screen were then checked against the catalogue for classic herbal usage. Finally, network pharmacology analysis was used to predict the general in vivo effects of each selected herb. RESULTS: Of the natural compounds screened, 13 that exist in traditional Chinese medicines were also found to have potential anti-2019-nCoV activity. Further, 125 Chinese herbs were found to contain 2 or more of these 13 compounds. Of these 125 herbs, 26 are classically catalogued as treating viral respiratory infections. Network pharmacology analysis predicted that the general in vivo roles of these 26 herbal plants were related to regulating viral infection, immune/inflammation reactions and hypoxia response. CONCLUSION: Chinese herbal treatments classically used for treating viral respiratory infection might contain direct anti-2019-nCoV compounds.

Exosomes from adipose-derived mesenchymal stem cells ameliorate cardiac damage after myocardial infarction by activating S1P/SK1/S1PR1 signaling and promoting macrophage M2 polarization.

Exosomes derived from mesenchymal stem cells (MSCs) are known to participate in myocardial repair after myocardial infarction (MI), but the mechanism remains unclear. Here, we isolated exosomes from adipose-derived MSCs (ADSCs) and examined their effect on MI-induced cardiac damage. To examine the underlying mechanism, H9c2 cells, cardiac fibroblasts, and HAPI cells were used to study the effect of ADSC-exosomes on hypoxia-induced H9c2 apoptosis, TGF-ß1-induced fibrosis of cardiac fibroblasts, and hypoxia-induced macrophage M1 polarization using qRT-PCR, western blot, ELISA, immunohistochemistry, immunofluorescence and flow cytometry. ADSC-exosome treatment mitigated MI-induced cardiac damage by suppressing cardiac dysfunction, cardiac apoptosis, cardiac fibrosis, and inflammatory responses in vitro and in vivo. In addition, ADSC-exosome treatment promoted macrophage M2 polarization. Further experiments found that S1P/SK1/S1PR1 signaling was involved in the ADSC-exosome-mediated myocardial repair. Silencing of S1PR1 reversed the inhibitory effect of ADSC-exosomes on MI-induced cardiac apoptosis and fibrosis in vitro. ADSC-exosome-induced macrophage M2 polarization was also reversed after downregulation of S1PR1 under hypoxia conditions, which promoted NFκB and TGF-ß1 expression, and suppressed the MI-induced cardiac fibrosis and inflammatory response. In sum, these results indicate that ADSC-derived exosomes ameliorate cardiac damage after MI by activating S1P/SK1/S1PR1 signaling and promoting macrophage M2 polarization.

Ropivacaine at different concentrations on intrapartum fever, IL-6 and TNF-α in parturient with epidural labor analgesia.

Effects of ropivacaine at different concentrations on intrapartum fever, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in parturient with epidural labor analgesia were compared to provide reference for the rational selection of anesthetics in clinic. Medical records of 198 cases of primi-paras admitted to the Obstetrics and Gynecology Department, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, from January 2017 to January 2018 were analyzed retrospectively and divided into 2 groups. A total of 105 patients were treated with 0.075% ropivacaine injection 10 ml and 0.5 µg/ml sulfentanyl injection 100 ml in parturition as the experimental group, and 93 patients were treated with 0.1% ropivacaine injection 10 ml and 0.5 µg/ml sulfentanyl injection 100 ml in parturition as the control group. After patient-controlled epidural analgesia, the pain visual analogue score (VAS), labor duration, administration time and febrile rate of parturient after administration were compared between the two groups at different time-points. Venous blood 2 ml was taken at T1 (cervix open to 2 cm), T2 (cervix fully open) and T3 (24 h postpartum), and the concentration of IL-6 TNF-α was detected by enzyme-linked immunosorbent assay. The time of the second stage of labor and analgesia were shorter in the experimental group than that in the control group after administration (P<0.05). The febrile rate of parturient in the experimental group was lower than that in the control group (P<0.05). The concentration of IL-6 and TNF-α in the experimental group was lower than that in the control group at T2 (P<0.05; P<0.01). The effect of patient-controlled epidural administration with 0.075% ropivacaine injection combined with 0.5 mg/ml sulfentanyl injection on labor analgesia is shorter than that with 0.1% ropivacaine combined with sulfentanyl. It could also shorten the duration of the second stage of labor, reduce the intrapartum febrile rate, and alleviate inflammation.

miR-93-5p-Containing Exosomes Treatment Attenuates Acute Myocardial Infarction-Induced Myocardial Damage.

Adipose-derived stromal cells (ADSCs) have been considered as an attractive therapeutic tool. Accumulating evidence indicates that the healing effects of ADSCs are mainly related to paracrine action rather than transdifferentiation. Data show that the expression of miR-93-5p has a cardio-protective effect after acute myocardial infarction (AMI). To identify whether miR-93-5p-encapsulating exosomes that form ADSCs have a better cardio-protective effect, we investigated the inflammatory factors and miR-30d-5p expression in clinical levels. A rat model of AMI and an in vitro model of hypoxic H9c2 cells were established to study the protective mechanism of miR-93-5p in ischemia-induced cardiac injury. The results show that the expression of inflammatory cytokines and miR-93-5p were increased following AMI in both patients and animal models. Moreover, treatment with ADSC-derived miR-93-5p-containing exosomes has a greater protective effect on infarction-induced myocardial damage than simple exosome processing. Furthermore, in vitro experiments confirmed that the expression of miR-93-5p can significantly suppress hypoxia-induced autophagy and inflammatory cytokine expression by targeting Atg7 and Toll-like receptor 4 (TLR4), respectively, and was confirmed with Atg7 or TLR4 overexpression. The results also show that autophagy activation can promote inflammatory cytokine expression indirectly. Taken together, these results suggest that the miR-93-5p-enhanced ADSC-derived exosomes prevent cardiac injury by inhibiting autophagy and the inflammatory response.

Cyclin D1-mediated microRNA expression signature predicts breast cancer outcome.

Background: Genetic classification of breast cancer based on the coding mRNA suggests the evolution of distinct subtypes. Whether the non-coding genome is altered concordantly with the coding genome and the mechanism by which the cell cycle directly controls the non-coding genome is poorly understood. Methods: Herein, the miRNA signature maintained by endogenous cyclin D1 in human breast cancer cells was defined. In order to determine the clinical significance of the cyclin D1-mediated miRNA signature, we defined a miRNA expression superset from 459 breast cancer samples. We compared the coding and non-coding genome of breast cancer subtypes. Results: Hierarchical clustering of human breast cancers defined four distinct miRNA clusters (G1-G4) associated with distinguishable relapse-free survival by Kaplan-Meier analysis. The cyclin D1-regulated miRNA signature included several oncomirs, was conserved in multiple breast cancer cell lines, was associated with the G2 tumor miRNA cluster, ERα+ status, better outcome and activation of the Wnt pathway. The coding and non-coding genome were discordant within breast cancer subtypes. Seed elements for cyclin D1-regulated miRNA were identified in 63 genes of the Wnt signaling pathway including DKK. Cyclin D1 restrained DKK1 via the 3'UTR. In vivo studies using inducible transgenics confirmed cyclin D1 induces Wnt-dependent gene expression. Conclusion: The non-coding genome defines breast cancer subtypes that are discordant with their coding genome subtype suggesting distinct evolutionary drivers within the tumors. Cyclin D1 orchestrates expression of a miRNA signature that induces Wnt/ß-catenin signaling, therefore cyclin D1 serves both upstream and downstream of Wnt/ß-catenin signaling.

Stromal cyclin D1 promotes heterotypic immune signaling and breast cancer growth.

The cyclin D1 gene encodes the regulatory subunit of a holoenzyme that drives cell autonomous cell cycle progression and proliferation. Herein we show cyclin D1 abundance is increased >30-fold in the stromal fibroblasts of patients with invasive breast cancer, associated with poor outcome. Cyclin D1 transformed hTERT human fibroblast to a cancer-associated fibroblast phenotype. Stromal fibroblast expression of cyclin D1 (cyclin D1Stroma) in vivo, enhanced breast epithelial cancer tumor growth, restrained apoptosis, and increased autophagy. Cyclin D1Stroma had profound effects on the breast tumor microenvironment increasing the recruitment of F4/80+ and CD11b+ macrophages and increasing angiogenesis. Cyclin D1Stroma induced secretion of factors that promoted expansion of stem cells (breast stem-like cells, embryonic stem cells and bone marrow derived stem cells). Cyclin D1Stroma resulted in increased secretion of proinflammatory cytokines (CCL2, CCL7, CCL11, CXCL1, CXCL5, CXCL9, CXCL12), CSF (CSF1, GM-CSF1) and osteopontin (OPN) (30-fold). OPN was induced by cyclin D1 in fibroblasts, breast epithelial cells and in the murine transgenic mammary gland and OPN was sufficient to induce stem cell expansion. These results demonstrate that cyclin D1Stroma drives tumor microenvironment heterocellular signaling, promoting several key hallmarks of cancer.

Neonatal Heart-Enriched miR-708 Promotes Proliferation and Stress Resistance of Cardiomyocytes in Rodents.

Adult heart has limited potential for regeneration after pathological injury due to the limited cell proliferation of cardiomyocytes and the quiescent status of progenitor cells. As such, induction of cell-cycle reentry of cardiomyocytes is one of the key strategies for regeneration of damaged heart. In this study, a subset of miRNAs including miR-708 were identified to be much more abundant in the embryonic and neonatal cardiomyocytes than that in adult rodents. Overexpression of miR-708 promoted cellular proliferation of H9C2 cells or primary cardiomyocytes from neonatal rats or mice in vitro. Lipid nanoparticle delivery of miR-708 promoted myocardial regeneration and heart function recovery in vivo. In addition, miR-708 protected cardiomyocytes against stress-induced apoptosis under hypoxia or isoproterenol treatments. miR-708 inhibited the expression of MAPK14, which has been demonstrated arresting the cell cycle in cardiomyocytes. The cell proliferation-promoting function of miR-708 was dependent at least partly on the expression of MAPK14. These findings strengthen the potential of applying miRNAs to reconstitute lost cardiomyocytes in injured hearts, and may provide a novel miRNA candidate for promoting heart regeneration.

C-Kit Positive Cardiac Stem Cells and Bone Marrow-Derived Mesenchymal Stem Cells Synergistically Enhance Angiogenesis and Improve Cardiac Function After Myocardial Infarction in a Paracrine Manner.

BACKGROUND: Stem cell transplantation offers a promising treatment for heart failure. Recent studies show that both c-kit positive cardiac stem cells (CSCs) and bone marrow-derived mesenchymal stem cells (BM-MSCs) are good candidates for stem cell therapy to treat heart failure; however, the exact mechanism of stem cell therapy in improving cardiac function of ischemic cardiomyopathy is not fully known. Our objective was to test our hypothesis that CSCs and/or BM-MSCs repair the damaged heart by boosting post-myocardial infarction (MI) angiogenesis in a paracrine manner. METHODS AND RESULTS: We isolated and purified CSCs and BM-MSCs from rats. Intramyocardial injections of CSCs and/or BM-MSCs were performed at 28 days after MI. We applied cardiac ultrasound and histological analysis to evaluate the effect of cell therapy on cardiac function and cardiac remodeling. In vivo donor cell transplantation experiments showed that CSCs and/or BM-MSCs improved cardiac function after MI and reduced infarct size. However, in vivo cell tracking experiments showed that minimal donor cells remained in the myocardium after cell transplantation. Our further in vitro and in vivo experiments showed that transplantation of CSCs enhanced the expression of pro-angiogenic factors and boosted post-MI angiogenesis in the myocardium in a paracrine manner, which in part contributed to the effect of CSCs on cardiac recovery after MI. CSCs and BM-MSCs synergistically inhibited CSC/BM-MSC apoptosis and enhanced their proliferation in a paracrine manner. This resulted in a larger number of transplanted cells remaining in the post-MI myocardium after coinjection of CSCs and BM-MSCs, and therefore the accumulation of more pro-angiogenic factors in the heart tissue compared to transplantation of CSCs or MSCs alone. Consequently, transplantation of both CSCs and BM-MSCs was superior to transplantation of either CSCs or BM-MSCs alone to boost post-MI angiogenesis and improve cardiac function after MI. CONCLUSION: C-kit+ CSC and/or BM-MSC transplantation can improve cardiac function after MI in a paracrine manner. Coinjection of both CSCs and BM-MSCs improves cardiac function more significantly than CSC or BM-MSC transplantation alone in a paracrine manner by improving the engraftment of donor cells and boosting the expression of multiple pro-angiogenic factors.

Small RNA zippers lock miRNA molecules and block miRNA function in mammalian cells.

MicroRNAs (miRNAs) loss-of-function phenotypes are mainly induced by chemically modified antisense oligonucleotides. Here we develop an alternative inhibitor for miRNAs, termed 'small RNA zipper'. It is designed to connect miRNA molecules end to end, forming a DNA-RNA duplex through a complementary interaction with high affinity, high specificity and high stability. Two miRNAs, miR-221 and miR-17, are tested in human breast cancer cell lines, demonstrating the 70∼90% knockdown of miRNA levels by 30-50 nM small RNA zippers. The miR-221 zipper shows capability in rescuing the expression of target genes of miR-221 and reversing the oncogenic function of miR-221 in breast cancer cells. In addition, we demonstrate that the miR-221 zipper attenuates doxorubicin resistance with higher efficiency than anti-miR-221 in human breast cancer cells. Taken together, small RNA zippers are a miRNA inhibitor, which can be used to induce miRNA loss-of-function phenotypes and validate miRNA target genes.

v-Src Oncogene Induces Trop2 Proteolytic Activation via Cyclin D1.

Proteomic analysis of castration-resistant prostate cancer demonstrated the enrichment of Src tyrosine kinase activity in approximately 90% of patients. Src is known to induce cyclin D1, and a cyclin D1-regulated gene expression module predicts poor outcome in human prostate cancer. The tumor-associated calcium signal transducer 2 (TACSTD2/Trop2/M1S1) is enriched in the prostate, promoting prostate stem cell self-renewal upon proteolytic activation via a γ-secretase cleavage complex (PS1, PS2) and TACE (ADAM17), which releases the Trop2 intracellular domain (Trop2 ICD). Herein, v-Src transformation of primary murine prostate epithelial cells increased the proportion of prostate cancer stem cells as characterized by gene expression, epitope characteristics, and prostatosphere formation. Cyclin D1 was induced by v-Src, and Src kinase induction of Trop2 ICD nuclear accumulation required cyclin D1. Cyclin D1 induced abundance of the Trop2 proteolytic cleavage activation components (PS2, TACE) and restrained expression of the inhibitory component of the Trop2 proteolytic complex (Numb). Patients with prostate cancer with increased nuclear Trop2 ICD and cyclin D1, and reduced Numb, had reduced recurrence-free survival probability (HR = 4.35). Cyclin D1, therefore, serves as a transducer of v-Src-mediated induction of Trop2 ICD by enhancing abundance of the Trop2 proteolytic activation complex. Cancer Res; 76(22); 6723-34. ©2016 AACR.

Neonatal Heart-Enriched miR-708 Promotes Differentiation of Cardiac Progenitor Cells in Rats.

Cardiovascular disease is becoming the leading cause of death throughout the world. However, adult hearts have limited potential for regeneration after pathological injury, partly due to the quiescent status of stem/progenitor cells. Reactivation of cardiac stem/progenitor cells to create more myocyte progeny is one of the key steps in the regeneration of a damaged heart. In this study, miR-708 was identified to be enriched in the neonatal cardiomyocytes of rats, but this has not yet been proven in adult humans. A lower level of miR-708 in c-kit(+) stem/progenitor cells was detected compared to non-progenitors. Overexpression of miR-708 induced cardiomyocyte differentiation of cardiac stem/progenitor cells. This finding strengthened the potential of applying miRNAs in the regeneration of injured hearts, and this indicates that miR-708 could be a novel candidate for treatment of heart diseases.

A direct quantification method for measuring plasma MicroRNAs identified potential biomarkers for detecting metastatic breast cancer.

Circulating miRNAs are protected from ribonuclease degradation by assembly into microvesicles and exosomes. Releasing miRNAs completely from these particles is the key step to quantify the circulating miRNAs. Currently purified RNA-based quantitative analysis is widely used while it is time and cost consuming with high risk for those circulating miRNAs with low abundance due to partial loss of RNA during the steps of total RNA extraction and small RNA enrichment. Herein, we optimized a simple, effective and time-saving method to directly measure plasma miRNAs without RNA isolation. It is based on complete miRNA release from the protein complexes, followed by miRNA-specific reverse transcription and quantitative real-time PCR amplification. By comparison to the RNA-based approach, the direct quantification method showed more efficiency for circulating miRNA analysis, higher accuracy and specificity. By application of the direct quantification method to clinical samples combined with the RNA-based miRNA screening analysis, upregulation of miR-106a in blood was validated in metastatic breast cancer patients, indicating miR-106a are a potential biomarker for metastatic breast cancer.

Long noncoding RNAs in regulation of human breast cancer.

Less than 2% of the human genome DNA is composed of protein-coding genes, although the majority of the human genome is transcribed, indicating the transcripts mostly are noncoding RNAs. Those noncoding RNAs with length between 200 nt and 200 kb are categorized as long noncoding RNA (lncRNA). Around 30 000 lncRNAs have been predicted or identified, although little is known regarding the regulatory function for a vast majority of these sequences. Emerging evidence demonstrated that lncRNAs play crucial roles in regulation of many cancer types, including breast cancer, serving as oncogenes or tumor suppressors. Aberrant and differential expression of lncRNA in breast cancer has been frequently reported. Their regulation of breast cancer is still the beginning to be elucidated. This review collected those experimentally validated lncRNAs in human breast cancer, summarizing their biological function as well as the regulatory mechanism. In addition, the potential of lncRNAs as biomarkers for better diagnosis or therapeutic targets for cancer treatment was discussed.