Targeting ONECUT3 blocks glycolytic metabolism and potentiates anti-PD-1 therapy in pancreatic cancer.

BACKGROUND: Reprogramming glucose metabolism, also known as the Warburg effect (aerobic glycolysis), is a hallmark of cancers. Increased tumor glycolysis not only favors rapid cancer cell proliferation but reprograms the immune microenvironment to enable tumor progression. The transcriptional factor ONECUT3 plays key roles in the development of the liver and pancreas, however, limited is known about its oncogenic roles, particularly metabolic reprogramming. METHODS: Immunohistochemistry and Western blotting are applied to determine the expression pattern of ONECUT3 and its clinical relevance in pancreatic ductal adenocarcinoma (PDAC). Knockdown and overexpression strategies are employed to determine the in vitro and in vivo functions of ONECUT3. Chromatin immunoprecipitation, luciferase reporter assay, and gene set enrichment analysis are used to decipher the molecular mechanisms. RESULTS: The glycolytic metabolism is inversely associated with T-cell infiltration in PDAC. ONECUT3 is identified as a key regulator for PDAC glycolysis and CD8+ T-cell infiltration. Genetic silencing of ONECUT3 inhibits cell proliferation, promotes cell apoptosis, and reduces glycolytic metabolism as evidenced by glucose uptake, lactate production, and extracellular acidification rate. Opposite effects of ONECUT3 are observed in overexpression studies. ONECUT3 enhances aerobic glycolysis via transcriptional regulation of PDK1. Targeting ONECUT3 effectively suppresses tumor growth, increases CD8+ T-cell infiltration, and potentiates anti-PD-1 therapy in PDAC. Pharmacological inhibition of PDK1 also shows a synergistic effect with anti-PD-1 therapy. In clinical setting, ONECUT3 is closely associated with PDK1 expression and T-cell infiltration in PDAC and acts as an independent prognostic factor. CONCLUSIONS: Our study reveals a previous unprecedented regulatory role of ONECUT3 in PDAC glycolysis and provides in vivo evidence that increased glycolysis is linked to an immunosuppressive microenvironment. Moreover, targeting ONECUT3-PDK1 axis may serve as a promising therapeutic approach for the treatment of PDAC.

Enhancement of PPARα-Inhibited Leucine Metabolism-Stimulated ß-Casein Synthesis and Fatty Acid Synthesis in Primary Bovine Mammary Epithelial Cells.

Leucine, a kind of branched-chain amino acid, plays a regulatory role in the milk production of mammalian mammary glands, but its regulatory functions and underlying molecular mechanisms remain unknown. This work showed that a leucine-enriched mixture (LEUem) supplementation increased the levels of milk protein and milk fat synthesis in primary bovine mammary epithelial cells (BMECs). RNA-seq of leucine-treated BMECs indicated alterations in lipid metabolism, translation, ribosomal structure and biogenesis, and inflammatory response signaling pathways. Meanwhile, the supplementation of leucine resulted in mTOR activation and increased the expression of BCKDHA, FASN, ACC, and SCD1. Interestingly, the expression of PPARα was independently correlated with the leucine-supplemented dose. PPARα activated by WY-14643 caused significant suppression of lipogenic genes expression. Furthermore, WY-14643 attenuated leucine-induced ß-casein synthesis and enhanced the level of BCKDHA expression. Moreover, promoter analysis revealed a peroxisome-proliferator-response element (PPRE) site in the bovine BCKDHA promoter, and WY-14643 promoted the recruitment of PPARα onto the BCKDHA promoter. Together, the present data indicate that leucine promotes the synthesis of ß-casein and fatty acid and that PPARα-involved leucine catabolism is the key target.

Overexpression of hsa_circ_0006470 inhibits the malignant behavior of gastric cancer cells via regulation of miR-1234/TP53I11 axis.

Gastric cancer (GC) is a subtype of a common malignant tumor found in the digestive system. Hsa_circ_0006470 is known to be closely associated with the development of GC. Nevertheless, the mechanism by which hsa_circ_0006470 regulates the tumorigenesis of GC has not been fully elucidated. To investigate the role of hsa_circ_0006470 in GC, its expression levels were assessed in GES-1, AGS, MKN45, and SNU5 cells by reverse transcription-quantitative PCR. Fluorescence in situ hybridization was used to evaluate the localization of hsa_circ_0006470 in AGS and MKN45 cells. In addition, cell counting kit-8 and 5-ethynyl-2'-deoxyuridine assays were performed to evaluate the viability and proliferation of GC cells, respectively. The dual-luciferase reporter assay was used to explore the interaction among hsa_circ_0006470, microRNA (miR)-1234, and TP53I11. The expression levels of TP53I11, Akt, p-Akt, forkhead box O1, and cyclin dependent kinase 2 in AGS cells were analyzed by Western blotting. The data indicated that hsa_circ_0006470 expression was downregulated in AGS cells. In addition, overexpression (OE) of hsa_circ_0006470 could inhibit the viability and proliferation of GC cells. Moreover, OE of hsa_circ_0006470 inhibited the migration of GC cells and induced G1 cell cycle phase arrest. Moreover, miR-1234 was bound to hsa_circ_0006470 and TP53I11 was targeted by miR-1234. Furthermore, OE of hsa_circ_0006470 inhibited the tumorigenesis of GC via the regulation of the miR-1234/TP53I11 axis. In summary, the present study demonstrated that OE of hsa_circ_0006470 notably inhibited the tumorigenesis of GC by regulating the miR-1234/TP53I11 axis. Therefore, the present study may provide a theoretical basis for exploring novel therapeutic strategies for the treatment of GC.

Simultaneous Determination of Fifteen Polyphenols in Fruit Juice Using Ultrahigh-Performance Liquid Chromatography-Tandem Mass Spectrometry Combining Dispersive Liquid-Liquid Microextraction.

Polyphenols are secondary metabolites of plants and used as effective antioxidants in dietary supplements, whose main sources are fruits, vegetables, and grains. To clarify the content and distribution of polyphenols in different fruit species samples accurately, a rapid and sensitive ultrahigh-pressure liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method combining dispersive liquid-liquid microextraction (DLLME) was developed for quantitative determination of fifteen polyphenol compounds in fruit juice. In this method, the targets were first extracted from 1 g of fruit juice sample using 10 mL of 80% ethanol solution by ultrasonic-assisted extraction (UAE). Then, 1.0 mL of UAE extracted solution, 60 µL of n-octanol and 2.0 mL of H2O were performed in the following DLLME procedure. A C18 reversed-phase column, ZORBAX SB (100 × 4.6 mm, 3.5 µm), was proposed under gradient elution with 0.1% formic acid aqueous solution and methanol mobile phases for the determination of 15 polyphenols, allowing us to obtain polyphenolic profiles in less than 23.0 min. Under the optimum conditions, the enrichment factors ranged from 162 to 194. The results showed that the 15 polyphenols had linear correlation coefficients (R 2) more than 0.99. The limits of detection (LODs) were between 18.3 and 103.5 ng/g, and the average recoveries were between 96.9 and 116.3% with interday relative standard deviations (RSDs) ranging from 4.4 to 8.2% in all cases. The method was successfully applied to the analysis of real fruit juice samples and presented itself as a simple, rapid, practical, and environment-friendly technique.

Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) overexpression alleviates endoplasmic reticulum stress after acute kidney injury.

BACKGROUND: Mitochondrial biogenesis dysregulation and enhanced endoplasmic reticulum (ER) stress have been implicated in the progression of acute kidney injury (AKI). However, the interaction between these two events remains poorly understood. This study was designed to investigate the role of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) expression, a key factor in mitochondrial biogenesis, in renal ER stress at 24 h after AKI and the underlying mechanisms. METHODS: Mice were administered recombinant adenovirus encoding murine PGC-1α (100 µl, 1.0 × 109PFU/ml) or vehicle five days before renal ischemia reperfusion (I/R) or sham operation. Twenty-four hours after the operation, kidney and serum samples were collected for evaluation. RESULTS: We first confirmed that PGC-1α transfection elevated the PGC-1α levels and mitochondrial transcripts in the kidney 24 h after AKI. Then, we found PGC-1α overexpression improved renal function. PGC-1α transfection inhibited AKI-induced ER stress through the unfolded protein response (UPR) pathway, resulting in the suppression of apoptosis via both mitochondrial and ER pathways. Further study showed that the expression of mitofusin 2 (Mfn2), an interaction protein between mitochondria and ER, was increased after PGC-1α overexpression. We also found the expression of a novel ER stress regulator, hairy and enhancer of split 1 (Hes1), was decreased after PGC-1α transfection. CONCLUSIONS: Our findings reveal that mitochondrial biogenesis plays an important role in the progression of AKI-induced ER stress and provide useful evidence for research on organelle crosstalk during AKI.

Long non-coding RNA HOTAIR/microRNA-761 sponge regulates PPME1 and further influences cell biological functions in thyroid carcinoma.

BACKGROUND: Most well-differentiated thyroid carcinomas display good therapeutic outcomes, but there are still some patients who are not sensitive to the general treatments lose their treatment opportunities. Thus, it is important to understand the molecular mechanisms that cause thyroid carcinoma, so as to find effective diagnostic and therapeutic targets. AIM OF THE STUDY: To explore the role of homeobox transcript antisense RNA (HOTAIR) in thyroid carcinoma through protein phosphatase methylesterase 1 (PPME1) by sponging microRNA 761 (miR-761). METHODS: The regulation network amongst HOTAIR, miR-761 and PPME1 was predicted by online sources. RT-PCR was conducted to evaluate the expression of HOTAIR and miR-761 in tumor tissues. Clinical data was collected and analyzed by Chi-square test. Cell apoptosis and proliferation was evaluated using three types of cancer cells (HTh-7, CAL-62, BCPAP) after treated with si-HOTAIR and miR-761inhibitor. The binding site among HOTAIR, miR-761 and PPME1 was verified by dual luciferase reporter assay. PPME1 expression was measured after HOTAIR and miR-761 were suppressed by western blot. Survival time was measured in nude mice using log-rank test. RESULTS: HOTAIR was expressed to a significantly greater extent than miR-761 in thyroid tumor tissues (P < .001). miR-761 and PPME1 were negatively correlated (coef = -1.91, P < .001). HOTAIR competitively binds to miR-761 and miR-761 directly targets PPME1. HOTAIR was highly correlated with TNM (χ 2 = 5.797, P = .016), tumor size (χ 2 = 7.955, P = .005) and lymphatic metastasis (χ 2 = 6.0, P = .014). HOTAIR promoted cell proliferation and inhibited cell apoptosis, whereas miR-761 did not. HOTAIR elevated and miR-761 suppressed PPME1 expression. HOTAIR expression appears to affect the survival time in vivo. CONCLUSION: HOTAIR regulated thyroid cancer cells by binding to miR-761 through PPME1.

Predictive Value of IL-6 Combined with NLR in Inflammation and Cancer.

The strong association between inflammation and cancer is reflected by the high interleukin-6 (IL-6) levels in the tumor microenvironment, where it promotes carcinogenesis by regulating all hallmarks of cancer and multiple signaling pathways. In this study, we investigated the prognostic value of IL-6 and other clinical indexes in inflammatory and cancer patients. All the patients were divided into the inflammation group (n = 400) and the cancer group (n = 672) composed of hematological malignancies group (n = 338) and solid tumors group (n = 334). Continuous variables were measured by one-way ANOVA and t-test, and the independent risk factors for carcinogenesis were determined by multivariate logistic regression analysis. The receiver operating characteristic (ROC) curves subsequently performed the predictive value of significant serological parameters and the Corheatmaps illustrated the correlation of these parameters in every case. Our retrospective study revealed that various serological indexes could reflect carcinogenesis in inflammatory patients, as significant differences existed in many indexes between them. It was notable that indicator composed of IL-6 and neutrophils/lymphocytes ratio (NLR) occupied the superior position of Area Under Curve (AUC) values in cancer cases, especially in patients with solid tumors (AUC = 0.85). The newly-found indicator could also be referred as an independent risk factor, which provided us with novel clues on the investigation of more reliable and affordable clinical indexes in tumor prediction.

Emerging roles of HOTAIR in human cancer.

Long noncoding RNA HOX antisense intergenic RNA (HOTAIR) is overexpressed in many types of cancers, and substantial evidence has suggested a link between cancers and HOTAIR. In the present study, we reviewed the structure and the corresponding biologic function of HOTAIR to clarify its molecular mechanism in cancer progression. HOTAIR promotes proliferation, invasion, and migration, and inhibits apoptosis in cancer cells. HOTAIR also participates in the pathogenesis and progression of cancer by regulating inflammation and immune signaling. These findings suggested that HOTAIR is a novel biomarker in human cancers.

miR-25 Promotes Cell Proliferation, Migration, and Invasion of Non-Small-Cell Lung Cancer by Targeting the LATS2/YAP Signaling Pathway.

Metastasis is the leading cause of high mortality in lung cancer patients, and metastatic lung cancer is difficult to treat. miRNAs are involved in various biological processes of cancer, including metastasis. Our previous studies revealed that miR-25 promoted non-small-cell lung cancer (NSCLC) cell proliferation and suppressed cell apoptosis by directly targeting TP53 and MOAP1. In this work, we further explored the miR-25 expression in NSCLC patients in the Cancer Genome Atlas (TCGA) database and measured the miR-25 expression levels in the tissues of NSCLC patients and cell lines. miR-25 was overexpressed in both NSCLC tissues and cell lines. NSCLC patients who expressed a higher level of miR-25 exhibited worse overall survival than those with a lower level of miR-25. Overexpression of miR-25 enhanced NSCLC cell migration and invasion, while the inhibition of miR-25 exhibited the opposite effects. We identified the large tumor suppressor homology 2 (LATS2) as a new target gene of miR-25 in lung cancer. The effects of miR-25 on promoting NSCLC cell migration and invasion were at least partially due to activation of the Hippo signaling pathway. Additionally, miR-25 antagomir inhibited xenograft tumor growth and metastasis by the upregulation of LATS2. Taken together, our findings demonstrate that miR-25 contribute to lung cancer cell proliferation and metastasis by targeting the LATS2/YAP signaling pathway, which implicate miR-25 as a promising therapeutic target for lung cancer metastasis. Given that oxidative stress induces the overexpression of miR-25 and plays a critical role in cancer progression, this study establishes miR-25 as an intermediate between oxidative stress and lung cancer metastasis.

Long Non-Coding RNA and Breast Cancer.

Breast cancer, one of the most common diseases among women, is regarded as a heterogeneous and complicated disease that remains a major public health concern. Recently, owing to the development of next-generation sequencing technologies, long non-coding RNAs have received extensive attention. Numerous studies reveal that long non-coding RNAs are playing important roles in tumor development. Although the biological function and molecular mechanisms of long non-coding RNAs remain enigmatic, recent researchers have demonstrated that an array of long non-coding RNAs express abnormally in cancers, including breast cancer. Herein, we summarized the latest literature about long non-coding RNAs in breast cancer, with a particular focus on the multiple molecular roles of regulatory long non-coding RNAs that regulate cell proliferation, invasion, metastasis, and apoptosis.

Putative endothelial progenitor cells do not promote vascular repair but attenuate pericyte-myofibroblast transition in UUO-induced renal fibrosis.

BACKGROUND: Putative endothelial progenitor cells (pEPCs) have been confirmed to participate in alleviation of renal fibrosis in several ischaemic diseases. However, their mechanistic effect on renal fibrosis, which is characterized by vascular regression and further rarefaction-related pathology, remains unknown. METHODS: To explore the effect and molecular mechanisms by which pEPCs act on unilateral ureteral obstruction (UUO)-induced renal fibrosis, we isolated pEPCs from murine bone marrow. In vivo, pEPCs (2 × 105 cells/day) and pEPC-MVs (microvesicles) were injected into UUO mice via the tail vein. In vitro, pEPCs were co-cultured with renal-derived pericytes. Pericyte-myofibroblast transition was evaluated using the myofibroblast marker α-smooth muscle actin (α-SMA) and pericyte marker platelet-derived growth factor receptor ß (PDGFR-ß). RESULTS: Exogenous supply of bone marrow-derived pEPCs attenuated renal fibrosis by decreasing pericyte-myofibroblast transition without significant vascular repair in the UUO model. Our results indicated that pEPCs regulated pericytes and their transition into myofibroblasts via pEPC-MVs. Co-culture of pericytes with pEPCs in vitro suggested that pEPCs inhibit transforming growth factor-ß (TGF-ß)-induced pericyte-myofibroblast transition via a paracrine pathway. CONCLUSION: pEPCs effectively attenuated UUO-induced renal fibrosis by inhibiting pericyte-myofibroblast transition via a paracrine pathway, without promoting vascular repair.

Identification of Circulating Long Noncoding RNA Linc00152 as a Novel Biomarker for Diagnosis and Monitoring of Non-Small-Cell Lung Cancer.

OBJECTIVE: Long noncoding RNAs (lncRNAs) have been reported to play vital roles in non-small-cell lung cancer (NSCLC). Recently, long noncoding RNA Linc00152 has been reported to play important roles in various cancers. In this study, our aim was to investigate its expression pattern and clinical significance and further evaluate its diagnostic value for NSCLC. METHODS: The levels of Linc00152 were detected in NSCLC tissues and plasma samples by quantitative real-time PCR (qRT-PCR). Receiver operating characteristic (ROC) curves were depicted to evaluate the diagnostic value. RESULTS: We found that Linc00152 levels were upregulated in both NSCLC tissues and plasma samples. Plasma Linc00152 levels were significantly lower in postoperative samples than in preoperative samples. Besides, high Linc00152 expression was significantly correlated with tumor size (r = 0.293, P = 0.005) and tumor stage (r = 0.324, P = 0.011). The ROC curves indicated that plasma Linc00152 has high diagnostic accuracy for NSCLC, and the area under curve (AUC) for NSCLC versus healthy was 0.816 (95% CI: 0.757-0.875). Moreover, we found that the combination of Linc00152 and CEA could provide a more powerful diagnosis efficiency than Linc00152 or CEA alone (AUC = 0.881, 95% CI: 0.836-0.926). CONCLUSIONS: Plasma Linc00152 could serve as a promising biomarker for diagnosing and monitoring NSCLC.

Interactions between plant proteins/enzymes and other food components, and their effects on food quality.

Plant proteins are the main sources of dietary protein for humans, especially for vegetarians. There are a variety of components with different properties coexisting in foodstuffs, so the interactions between these components are inevitable to occur, thereby affecting food quality. Among these interactions, the interplay between plant proteins/enzymes from fruits and vegetables, cereals, and legumes and other molecules plays an important role in food quality, which recently has gained a particular scientific interest. Such interactions not only affect the appearances of fruits and vegetables and the functionality of cereal products but also the nutritive properties of plant foods. Non-covalent forces, such as hydrogen bond, hydrophobic interaction, electrostatic interaction, and van der Waals forces, are mainly responsible for these interactions. Future outlook is highlighted with aim to suggest a research line to be followed in further studies.

Glutaminolysis Was Induced by TGF-ß1 through PP2Ac Regulated Raf-MEK-ERK Signaling in Endothelial Cells.

Vascular endothelial cells can survive under hypoxic and inflammatory conditions by alterations of the cellular energy metabolism. In addition to high rates of glycolysis, glutaminolysis is another important way of providing the required energy to support cellular sprouting in such situations. However, the exact mechanism in which endothelial cells upregulate glutaminolysis remains unclear. Here we demonstrated that protein phosphatase 2A (PP2A)-mediated Raf-MEK-ERK signaling was involved in glutaminolysis in endothelial cells. Using models of human umbilical vein endothelial cells (HUVECs) treated with transforming growth factor-ß1 (TGF-ß1), we observed a dramatic induction in cellular glutamate levels accompanied by Raf-MEK-ERK activation. By addition of U0126, the specific inhibitor of MEK1/2, the expression of kidney-type glutaminase (KGA, a critical glutaminase in glutaminolysis) was significantly decreased. Moreover, inhibition of PP2A by okadaic acid (OA), a specific inhibitor of PP2A phosphatase activity or by depletion of its catalytic subunit (PP2Ac), led to a significant inactivation of Raf-MEK-ERK signaling and reduced glutaminolysis in endothelial cells. Taken together, these results indicated that PP2A-dependent Raf-MEK-ERK activation was involved in glutaminolysis and inhibition of PP2A signals was sufficient to block Raf-MEK-ERK pathway and reduced glutamine metabolism in endothelial cells.

A novel arylbenzofuran induces cervical cancer cell apoptosis and G1/S arrest through ERK-mediated Cdk2/cyclin-A signaling pathway.

7-hydroxy-5,4'-dimethoxy-2-arylbenzofuran (Ary) is purified from Livistona. It has been demonstrated to have anticancer activity to various tumors in including cervical cancer, but its mechanism is still unclear. In the present, we show that Ary induces cervical cancer cells apoptosis through mitochondria degradation and mediates cervical cancer cell arrest. Further, Ary-inducing cell cycle G1/S-phase arrest is associated with increased cyclin A2 and cyclin dependent kinase 2 (Cdk2) proteins. Knockdown of cyclin A2 using small interfering RNA (siRNA), and inhibiting Cdk2 activity with flavopiridol, strikingly reduced G1/S-phase arrest. Moreover, Ary sustainedly induced phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2). And ERK1/2 phosphorylation inhibition using specific inhibitor U0126 effectively suppressed cyclin A2 expression, and reduced G1/S-phase arrest induced by Ary. All the experiments in vitro and in vivo verified that Ary has an anticancer effect on cervical cancer. These data provide novel evidences that Ary induces cervical cancer cells apoptosis through mitochondria degradation and cell G1/S-phase arrest. These findings also suggest that ERK-mediated Cdk2/cyclin A signaling pathway is involved in Ary-induced G1/S-phase arrest.

Analysis of 4931 renal biopsy data in central China from 1994 to 2014.

The purpose of this study is to investigate the changing spectrum and clinicopathologic correlation of biopsy-proven renal diseases in central China. We retrospectively analyzed data of 4931 patients who underwent renal biopsy in ten hospitals between September 1994 and December 2014. Among them, 81.55% were primary glomerular diseases (GD), and 13.02% were secondary GD. IgA nephropathy (IgAN) was the most common primary GD (43.45%), followed by focal glomerulonephritis (16.79%), mesangial proliferative glomerulonephritis (MsPGN, 14.35%), and membranous nephropathy (MN, 13.28%). IgAN was leading primary GD in patients under 60 years old, while MN was the leading one over 60 years old. The most frequent secondary GD was lupus nephritis (LN) (47.35%). The prevalence of IgAN, MN and minimal change disease was found to increase significantly (p < 0.001, p < 0.001, and p < 0.01, respectively), while that of MsPGN, membranoproliferative glomerulonephritis and LN decreased significantly (p < 0.001, p < 0.001, and p < 0.05, respectively). The main indication for renal biopsy was proteinuria and hematuria (49.03%), followed by nephrotic syndrome (NS, 20.36%). IgAN was the most common cause in patients with proteinuria and hematuria, chronic-progressive kidney injury, hematuria and acute kidney injury; and MN was the leading cause of NS. Primary GD remained the predominant renal disease in central China. IgAN and LN were the most prevalent histopathologic lesions of primary and secondary GD, respectively. The spectrum of biopsy-proven renal disease had a great change in the past two decades. Proteinuria and hematuria was the main indication for renal biopsy.

Toehold enabling stem-loop inspired hemiduplex probe with enhanced sensitivity and sequence-specific detection of tumor DNA in serum.

The sensitivity of structure-switchable electrochemical DNA (E-DNA) sensors is generally limited by the irremovable redox labels that are close to or distant from the sensing interface. To address this issue, we design a semiduplex probe inspired by the stem-loop structure, in which the "nicked loop" domain can serve as toehold to mediate a target-responsive strand-displacement reaction. Such a reaction can fundamentally eliminate the post-responsive background current that arises from the irremovable probe, and thus improve the sensitivity. This novel toehold E-DNA (tE-DNA) sensor is able to achieve a detection limit as low as 0.2pM, which is lower than that of the classic stem-loop structured sensor by two orders of magnitude. Moreover, the toehold domain endows the sensor an excellent selectivity against a single-base mismatched sequence and high binding kinetics. By combining this heterogeneous surface-based dynamic self-assembly design with a homogeneous enzyme amplification strategy, the sensitivity can be further improved by three orders of magnitude to sub-femtomolar level. Additionally, this unique biosensor presents reliable reusability, and is capable of probing low abundance of target DNA directly in complex matrices, such as human serum, with minimal interference. These advantages make our tE-DNA sensor a promising contender in the E-DNA sensor family for clinical diagnostics.

miR-155 acts as an anti-inflammatory factor in atherosclerosis-associated foam cell formation by repressing calcium-regulated heat stable protein 1.

Atherosclerosis (AS) is chronic inflammation in response to lipid accumulation. MicroRNA-155 (miR-155) is being increasingly studied to evaluate its potential as diagnostic biomarkers and therapeutic targets in many diseases. However, delineating the role of miR-155 in AS remains difficult. Here, we detected constitutive expression of several microRNAs (miRNAs) possibly associated with cardiovascular disease in foam cells and clinical specimens from patients with AS. Among them, we found that the level of miR-155 in foam cells was the most significantly elevated in a dose- and time-dependent manner. In addition, the expression of miR-155 was elevated in the plasma and plaque of patients with AS. We also reported for the first time that miR-155 targets calcium-regulated heat stable protein 1 (CARHSP1), which regulates the stability of tumor necrosis factor alpha (TNF-α) mRNA. Furthermore, we investigated the mechanism by which the miR-155 level is elevated. miR-155 upregulation is due to transcriptional regulation by nuclear factor (NF)-κB, which is activated by the inflammatory factor TNF-α. In summary, increased miR-155 relieves chronic inflammation by a negative feedback loop and plays a protective role during atherosclerosis-associated foam cell formation by signaling through the miR-155-CARHSP1-TNF-α pathway.

Isolation and characterisation of tropomyosin from shrimp (Penaeus vannamei Boone) and its association property at high ionic strength.

Shrimps are important and highly demanded seafood, but they have been reported as a cause of food hypersensitive reaction. The major allergen of shrimp is tropomyosin (TM). However, so far, there has been few report on such purification procedure. In this study, we developed a strategy for the purification of TM from shrimp (Penaeus vannamei Boone). Subsequently, we demonstrated that the apparent MW of this protein is about 66 kDa, and this protein naturally contains two subunits (38.5 and 36.6 kDa) with a ratio of 1 to 1. Interestingly, different from other known TMs from vertebrates, shrimp TM can self-assemble into nanofibres at high ionic strength induced by ATP. These findings help to understand the structure and polymerisation property of TM from shrimps.

Formation of copper nanoparticles on poly(thymine) through surface-initiated enzymatic polymerization and its application for DNA detection.

Poly(thymine) (polyT) and double-stranded DNA (dsDNA) can act as efficient templates for the formation of copper nanoparticles (CuNPs) at a low concentration of CuSO4, and the formed CuNPs emit excellent fluorescence. In this work, we demonstrated a new and facile strategy for the highly sensitive and selective detection of DNA on streptavidin-functionalized magnetic beads (SA-MB) using DNA-templated CuNPs as the fluorescent probe. Target DNA (tDNA) was hybridized with the capture DNA that was immobilized on the surface of SA-MB. Surface initiated enzymatic polymerization (SIEP) was employed as the signal amplification method to generate the polyT at the 3' end of tDNA for the formation of CuNPs. The incorporation of polyT by SIEP resulted in ∼35.7 fold signal amplification compared to the dsDNA after hybridization without SIEP. A dose-response curve for detection of DNA was obtained, with a linear dynamic range of 0.1 nM to 10 nM. We showed that this method has a low pM limit of detection (LOD 98.2 pM) and it is also very sensitive to the mismatch type in a specific DNA sequence. In addition, it avoids rigorously controlled temperature, complex synthesis of the fluorescent probe and prelabeling of DNA strands and eliminates the use of sophisticated experimental techniques and equipment. Armed with these intriguing properties, the proposed system could provide an efficient tool for early diagnosis and risk assessment of malignancy.