Small molecules modulating biogenesis or processing of microRNAs with therapeutic potentials

MicroRNAs (miRNAs) are single-stranded non-coding RNAs with the ability to regulate gene expression at post-transcriptional level. Typically, miRNAs function by binding to the 3' untranslated regions (UTR) of target mRNAs, leading to the degradation or repressed expression of target genes. It is estimated that miRNAs are involved in almost every genetic pathway and the regulation of miRNAs plays important roles in physiological and pathological processes. Small molecules that can regulate miRNAs have great potential as probes to explore miRNAs-mediated regulatory network. Small-molecule regulators of disease-related miRNAs also hold the potential as novel therapeutic agents. Based on the screening systems developed in recent years, several small-molecule regulators have been identified as specific or universal regulators of miRNAs. Therapeutic potentials of these small molecules have also been demonstrated. A general review on the reported small molecules modulating the biogenesis or function of miRNAs will be presented in this paper, with emphasis on the screening methods, proposed mechanism of action and the therapeutic potentials of these small molecules.

siRNA targeting prohibitins inhibits proliferation and promotes apoptosis of gastric carcinoma cell line SGC7901 in vitro and in vivo

In the present study we investigate the effects of small interfering RNA (siRNA)-mediated silencing of prohibitins (Phbs) gene expressions on gastric carcinoma cell proliferation and apoptosis in vitro and in vivo. Firstly, Phbs proteins in five human gastric carcinoma cell lines were evaluated by Western blotting. Then three siRNA sequences targeting Phbs were designed and transfected into the cancer cell line with the highest Phbs protein expressions. The cell proliferation and apoptosis were analyzed by MTT and flow cytometry methods. In vivo, the effects of siRNAs on the proliferation and apoptosis were assayed in xenografted tumors of nude mice. Phbs proteins were expressed highest in gastric carcinoma cell line SGC7901. The cell proliferation significantly decreased upon Phbs silencing. The cell percentage in S phase was significantly lower in Phbs silenced groups, and the apoptotic cell ratio was significantly higher. siRNA targeting Phbs significantly inhibited the growth of the xenografted tumors. Further, Bcl-2 and Bax was respectively downregulated and upregulated after the Phbs silencing in the xenografted tumors. Caspase-3 and caspase-9 activities were significantly enhanced in the Phbs-silenced tumors. In summary, siRNA-mediated silencings of Phbs inhibit proliferation and promotes apoptosis of gastric carcinoma cells SGC7901 in vitro and in vivo, suggesting key roles of Phbs in the development of SGC7901 cell line.

The FEN1 E359K germline mutation disrupts the FEN1-WRN interaction and FEN1 GEN activity, causing aneuploidy-associated cancers

Polymorphisms and somatic mutations in Flap Endonuclease 1 (FEN1), an essential enzyme involved in DNA replication and repair, can lead to functional deficiencies of the FEN1 protein and a predisposition to cancer. We identified a FEN1 germline mutation which changed residue E359 to K in a patient whose family had a history of breast cancer. We determined that the E359K mutation, which is in the protein-protein domain of FEN1, abolished the interaction of FEN1 with Werner Syndrome protein (WRN), an interaction which is critical for resolving stalled DNA replication forks. Furthermore, although the flap endonuclease activity of FEN1 E359K was unaffected, it failed to resolve bubble structures, which requires the FEN1 gap dependent endonuclease (GEN) activity. To determine the etiological significance of E359K, we established a mouse model containing this mutation. E359K mouse embryonic fibroblasts (MEF) were more sensitive to DNA cross-linking agents that cause replication forks to stall. Cytological analysis suggested that the FEN1-WRN interaction was also required to for telomere stability; mutant cell lines had fragile telomeres, increased numbers of spontaneous chromosomal anomalies and higher frequencies of transformation. Moreover, the incidence of cancer was significantly higher in mice homozygous for FEN1 E359K than in wild-type mice, suggesting that the FEN1 E359K mutation is oncogenic.

Galectin-1 overexpression promotes progression and chemoresistance to cisplatin in epithelial ovarian cancer

This study was performed to investigate the role of galectin-1 (Gal-1) in epithelial ovarian cancer (EOC) progression and chemoresistance. Tissue samples from patients with EOC were used to examine the correlation between Gal-1 expression and clinical stage of EOC. The role of Gal-1 in EOC progression and chemoresistance was evaluated in vitro by siRNA-mediated knockdown of Gal-1 or lentivirus-mediated overexpression of Gal-1 in EOC cell lines. To elucidate the molecular mechanisms underlying Gal-1-mediated tumor progression and chemoresistance, the expression and activities of some signaling molecules associated with Gal-1 were analyzed. We found overexpression of Gal-1 in advanced stages of EOC. Knockdown of endogenous Gal-1 in EOC cells resulted in the reduction in cell growth, migration, and invasion in vitro, which may be caused by Gal-1's interaction with H-Ras and activation of the Raf/extracellular signal-regulated kinase (ERK) pathway. Additionally, matrix metalloproteinase-9 (MMP-9) and c-Jun were downregulated in Gal-1-knockdown cells. Notably, Gal-1 overexpression could significantly decrease the sensitivities of EOC cells to cisplatin, which might be ascribed to Gal-1-induced activation of the H-Ras/Raf/ERK pathway and upregulation of p21 and Bcl-2. Taken together, the results suggest that Gal-1 contributes to both tumorigenesis and cisplatin resistance in EOC. Thus, Gal-1 is a potential therapeutic target for EOC.

Adenosine 5'-monophosphate ameliorates D-galactosamine/lipopolysaccharide-induced liver injury through an adenosine receptor-independent mechanism in mice

D-galactosamine (GalN)/lipopolysaccharide (LPS)-induced lethality and acute liver failure is dependent on endogenously produced inflammatory cytokines. Adenosine has been proven to be a central role in the regulation of inflammatory response. It is not entirely clear that which adenosine action is actually crucial to limiting inflammatory tissue destruction. Here we showed that GalN/LPS challenge elevated hepatic adenosine and induced lethality in adenosine receptor-deficient mice with equal efficiency as wild-type mice. In GalN/LPS-treated mice, pretreatment with adenosine 5'-monophosphate (5'-AMP) significantly elevated hepatic adenosine level and reduced mortality through decreasing cytokine and chemokine production. In RAW264.7 cells, 5'-AMP treatment inhibited the production of inflammatory cytokines, which is not mediated through adenosine receptors. 5'-AMP failed to attenuate LPS-induced nuclear factor-κB (NF-κB) p65 nuclear translocation, but reduced LPS-induced recruitment of NF-κB p65 to inflammatory gene promoters and decreased LPS-induced enrichment of H3K4 dimethylation at the tumor necrosis factor-α (TNF-α) promoter, which was involved in 5'-AMP-induced elevation of cellular adenosine and a decline of methylation potential. In vitro biochemical analysis revealed that adenosine directly attenuated recruitment of NF-κB to the TNF-α and interleukin-6 promoters. Our findings demonstrate that 5'-AMP-inhibiting inflammatory response is not mediated by adenosine receptors and it may represent a potential protective agent for amelioration of LPS-induced liver injury.

Structure and photoluminescence characteristics of europium(iii) doped in CaAl2Si2O8phosphors

A series of Eu³⁺activated CaAl₂Si₂O₈phosphors have been synthesized at 1350 °C in air, and their photoluminescence properties have been investigated as a function of activator concentrations.

Relationship between exposure to extremely low-frequency electromagnetic fields and breast cancer risk: a meta-analysis

OBJECTIVE

To comprehensively analyze the relationship between human exposure to extremely low frequency electromagnetic fields (ELF-EMFs) and breast cancer and to discuss the potential risk of ELF-EMFs to human breast cancer.

MATERIALS AND METHODS

Sixteen research reports of case-control studies which were published from 2000 to 2007 were collected. The fixed effect model (FEM) or the random effect model (REM) was chosen to calculate total ORs depending on the outcomes of the test of homogeneity (Q test): the subgroup was analyzed with the menopause and the non-menopause.

OUTCOME

Sixteen research outcome was ORDL = 1.10, 95% CI = (1.01, 1.20), the OR(MH) of the non-menopause status group was 1.25, 95% CI = (1.05, 1.49), the OR(MH) of the menopause status group was OR(MH) = 1.04, 95% CI = (0.93, 1.18).

CONCLUSION

The authors found that ELF-EMFs may be increase the risk of human breast cancer. The women's exposure to ELF-EMFs may be the risk factor of breast cancer when they are non-menopausal.

Epidemiologic investigation of polycystic ovarian syndrome (PCOS) in Han ethnic women of reproductive age in Liaoning Province, China

OBJECTIVE

To determine the incidence of polycystic ovary syndrome (PCOS) among Han women of reproductive age in Liaoning Province in Northeastern China, based on the Revised Rotterdam 2003 criteria.

MATERIALS AND METHODS

A retrospective cohort study was carried out on 1,600 women using questionnaires, physical examination, ultrasonography, and biochemical indices (aged = 19 to 45 years; n = 1,600). PCOS patients were identified using the Revised Rotterdam 2003 criteria.

RESULTS

A total of 132 Han women of reproductive age were diagnosed with PCOS, with a prevalence of 8.25%. The prevalence of menstrual dysfunction was as follows: 97 patients (73.48%) had abnormal menstruation, three (2.27%) had polymenorrhea, and 94 (71.21%) had oligomenorrhea. Up to 64 patients (48.48%) had androgen excess, 42 (31.82%) had biochemical evidence of androgen excess, and 34 (25.76%) had clinical androgen excess. Up to 34 patients (25.76%) were obese (body mass index [BMI] > or = 25) and 19 (14.39%) had hirsutism (F-G scoring > or = 6). A total of 127 patients (96.22%) were diagnosed with PCOS via ultrasonography, 67 of whom (50.76%) had a unilateral polycystic ovary and 60 (45.46%) had bilateral polycystic ovaries.

CONCLUSIONS

The prevalence of PCOS in this study population was 8.25%, with an infertility rate of 27.8%. The classical manifestation of PCOS is PCO, abnormal menstruation, and obesity. The high-risk factors of PCOS include high free testosterone index, homeostasis model assessment-insulin resistance (HOMA-IR), increased serum testosterone and androstenedione, decreased sex hormone-binding globulin, long history of infertility, menarche later than 16 years old, and failure to have regular menstruation within two years.

Kinetics of serological responses in influenza A(H7N9)-infected patients correlate with clinical outcome in China, 2013

The novel avian influenza A(H7N9) infection has recently emerged to cause severe respiratory illness in China. The objectives of this study were to define the kinetics of the antibody responses in patients with influenza A(H7N9) disease and to correlate these kinetics with clinical outcome. Serial serum samples were obtained at intervals of three to four days from 18 patients with virologically confirmed A(H7N9) disease in Shanghai. We determined the kinetics of the haemagglutination inhibition (HI) and A(H7H9) pseudotype neutralisation antibody (Nab) responses and correlated these with clinical outcomes. Most patients had robust serological responses by both HI and Nab tests. Taking into account censoring due to time of testing and death, the median time from onset of illness to Nab titre ≥1:40 was 14 days (95% confidence interval (CI): 11–18 days) in the fatal cases and 10.5 days (95% CI: 7–12) in the survivors (p=0.003). The two groups did not differ in initial Nab titres, but the rate of increase in Nab titres was significantly faster for survivors by approximately 10-fold per 15 days (p=0.007). Early and rapid induction of Nab was correlated significantly with better clinical outcome.

Eutectic condensation and nucleation in vapor-liquid-solid grown ZnO nanorod arrays on Si substrate

It is very important to understand the growth mechanism of ZnO nanostructures for control of the morphologies and further design of optoelectronic devices. In this paper, the eutectic condensation of Zn vapor and catalyst Au, nucleation and epitaxy of ZnO nanorods were intuitionally observed in chemical vapor deposition process by controlling the temperature and atmosphere. The vertically aligned ZnO nanorod arrays were fabricated on Au-coated Si substrate. A Zn-riched buffer layer was found on Si substrate. Under the atmosphere nearly without O2, it was clearly observed that the nano-sized sprouts appeared on the buffer layer and Au-Zn condensed bigger and bigger with increase of temperature. When the O2 was introduced, the as-grown nanorods almost kept the same size and density with those sprouts grown at the same temperature without O2. The morphologies and composition analysis provided direct evidence for a bottom-catalyzed vapor-liquid-solid mechanism of ZnO nanorod arrays on the lattice-mismatched substrate.

Case-control study of risk factors for human infection with influenza A(H7N9) virus in Jiangsu Province, China, 2013

We describe a case-control study performed in Jiangsu, China, to evaluate risk factors for human infection with novel avian influenza A(H7N9) virus. Twenty-five cases and 93 controls matched by age, sex, and location were included in the study. Direct contact with poultry or birds in the two weeks before illness onset, chronic medical conditions (hypertension excluded), and environment-related exposures were significantly associated with A(H7N9) infection.

Diabetes impairs mobilization of mouse bone marrow-derived Lin(-)/VEGF-R2(+) progenitor cells

Endothelial progenitor cells circulating in the peripheral blood (PB) contribute to vascular repair. This study aimed to evaluate the potential of a 'cocktail' consisting of erythropoietin, granulocyte colony-stimulating factor and tetrahydrobiopterin to mobilize hematopoietic lineage negative/vascular endothelial growth factor receptor 2 positive (Lin(-)/VEGF-R2(+)) cells from the bone marrow (BM) to PB in non-diabetic and diabetic mice. Diabetes was induced in mice by intraperitoneal injection of streptozotocin. Diabetic mice were studied after 16weeks of hyperglycemia. Half the mice in each group (non-diabetic and diabetic) received daily intraperitoneal injections of the cocktail for 6 consecutive days while the other half received vehicle buffer. Mobilization of Lin(-)/VEGF-R2(+) cells, which were expanded in MCP301 medium, was evaluated after isolating them from BM and PB and their phenotypic and morphological properties were studied. We found that 16weeks of diabetes affected neither the total number of BM mononucleated cells nor the number of Lin(-)/VEGF-R2(+) cells in BM compared with non-diabetic controls. In non-diabetic mice, cocktail treatment resulted in a significant decrease in BM Lin(-)/VEGF-R2(+) cells, paralleled by a significant increase of these cells in PB. Such changes in the number of Lin(-)/VEGF-R2(+) cells in BM and PB after the cocktail treatment were less marked in diabetic mice. In vitro studies of BM Lin(-)/VEGF-R2(+) cells from diabetic and non-diabetic mice did not reveal any differences in either phenotypes or colony forming potential. These findings indicate that diabetes impairs the mobilization of Lin(-)/VEGF-R2(+) cells from BM to PB. Impaired mobilization of BM Lin(-)/VEGF-R2(+) cells soon after the onset of diabetes may contribute to complications such as diabetic retinopathy.

Inhibition of transforming growth factor beta-activated kinase 1 confers neuroprotection after traumatic brain injury in rats

The transforming growth factor beta-activated kinase 1 (TAK1), a member of the Mitogen-activated protein kinase kinase kinase family, is characterized as a key regulator in inflammatory and apoptosis signaling pathways. The aim of the present study was to evaluate the role of the TAK1 pathway in experimental traumatic brain injury (TBI) in rats. Adult male Sprague-Dawley rats were subjected to TBI using a modified Feeney's weight-drop model. The time course showed that a significant increase of TAK1 and p-TAK1 expression in the cortex after TBI. Moreover, TBI induced TAK1 redistribution both in neurons and astrocytes of the lesion boundary zone. The effects of specific inhibition of the TAK1 pathway by 5Z-7-oxozeaenol (OZ, intracerebroventricular injection at 10min post-trauma) on histopathological and behavioral outcomes in rats were assessed at 24h post injury. The number of TUNEL-positive stained cells was diminished and neuronal survival and neurological function were improved with OZ treatment. Biochemically, the high dose of OZ significantly reduced the levels of TAK1 and p-TAK1, further decreased nuclear factor-κB and activator protein 1 activities and the release of inflammatory cytokines. In addition, we found that both 10min and 3h post-trauma OZ therapies could markedly improve neurological function and neuronal survival after long-term survival. These results revealed that the TAK1 pathway is activated after experimental TBI and the inhibitor OZ affords significant neuro- protection and amelioration of neurobehavioral deficits after experimental TBI, suggesting a potential rationale for manipulating this pathway in clinical practice.

Biotribological properties at the stem-cement interface lubricated with different media

BACKGROUND

Debonding of the stem-cement interface occurs inevitably in-vivo under physiological loading, and pseudo-synovial fluid is subsequently pumped into this interface, serving as the lubricant. However, the influence of protein adsorption onto the femoral stem surface has not been well taken into consideration in previous in vitro studies.

MATERIALS AND METHODS

The biotribological properties at the stem-cement interface were investigated through a series of fretting frictional tests using polished stainless steel 316L stem and smooth bone cement, lubricated by three different media at body temperature, i.e. 100% calf serum, 25% calf serum, and 0.9% saline solution. The surface characterization of the femoral stem was evaluated sequentially using optical microscope, optical interferometer, scanning electron microscope, and Raman spectroscopy.

RESULTS

The friction coefficient generally kept stable during the test, and the minimum value (0.254) was obtained when 100% calf serum was used as the lubricant. Slight scratches were detected within the contact area for the stainless steel 316L stems lubricated by 100% calf serum and 25% calf serum, which was further surrounded by the adsorbed protein film with alveolate feature. Additionally, a wear scar was present within the contact area when 0.9% saline solution was used as the lubricant.

CONCLUSIONS

Protein adsorption onto the stainless steel 316L stem surface affected the biotribological properties at the stem-cement interface under oscillatory fretting mechanism. Generation of wear debris at the stem-cement interface may be postponed by modification of physicochemical properties of the femoral stem to promote protein adsorption.

Abstract P6-07-43: The Maximum Standardized Uptake Value of18F-FDG to Prognosticate Prognosis of Hormone-Receptor Positive Metastatic Breast Cancer

Objectives: The purpose of this prospective study was to determine whether baseline maximum standard uptake value (SUVmax) in metastatic breast cancer (MBC) patients correlates with validated prognostic markers and their luminal subtypes. Whether baseline SUVmax could be used as a noninvasive indicator to differentiate luminal A from luminal B subtypes and whether it could help predict the survival of these patients were also investigated.

Methods: MBC patients with luminal subtypes were screened with PET/CT from February 2007 until December 2010. Patients were included if they had previously undergone radical surgery, had at least one measurable metastatic lesion with abnormal fluorine-18-fluorodeoxyglucose (18F-FDG) uptake, and had not received treatment in the metastatic setting. Baseline information of eligible patients was collected and a prospective follow-up was conducted. SUVmax values were independently reviewed by two experienced nuclear medicine radiologists. The impact of different clinical parameters including luminal types on baseline SUVmax, was evaluated by Mann-Whitney U test (between 2 groups) or Kruskal-Wallis test (≥3 groups). Receiver operator characteristic (ROC) curves were used to identify potential SUV cutoffs predictive of different luminal subtype. Kaplan-Meier method was applied for survival analysis. Prognostic variables identified by univariate analysis (with P < 0.1) were analyzed in the multivariate Cox model.

Results: In total, 305 MBC patients with luminal subtypes were screened and 134 were eligible for this study including 75 (56.0%) luminal A type and 59 (44.0%) luminal B type. The median age was 52 years (range, 28–74 years) and median follow-up time was 26.6 months (range, 14.1–51.2 months). Baseline SUVmax was significantly related to the number of metastatic organs (p = 0.002) and existence of visceral metastasis (p = 0.009) on univariate analysis but could not effectively differentiate patients with luminal A subtype from those with luminal B subtype (area under ROC curve was 0.516 ± 0.052). Most importantly, although luminal subtypes diagnosed according to resected specimen from the first operation could predict the relapse-free interval (RFI) (P < 0.001), they could not predict progression-free survival (PFS) (p = 0.550) and overall survival (OS) (p = 0.233) after relapse or metastasis. However, baseline SUVmax did predict PFS and OS (p = 0.002 and p = 0.009, respectively). Baseline SUVmax, RFI, and the number of metastatic organs were three independent prognostic factors for PFS, while the significant predictors of OS in the COX regression model were baseline SUVmax and RFI. Using the tertile with the lowest SUVmax as the reference group, patients in the highest tertile of SUVmax had the shortest PFS (hazard ratio, 2.063; 95% confidence interval, 1.234–3.447) and OS (hazard ratio, 3.543; 95% confidence interval, 1.661–7.554).

Conclusions: Baseline SUVmax of MBC did not correlate with molecular subtypes of the primary tumor. In discriminating prognosis of luminal type breast cancer, molecular subtype is a valuable prognostic factor at primary diagnosis, but it is SUVmax, rather than molecular subtype, that is a potential surrogate marker for survival with metastatic disease.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-07-43.

Association of the interleukin-10 gene polymorphism (-1082A/G) with systemic lupus erythematosus: a meta-analysis

OBJECTIVE

The interleukin-10 (IL-10) gene polymorphism (-1082A/G) has been shown to be associated with systemic lupus erythematosus (SLE), but findings are not consistent across studies. The aim of our meta-analysis was to assess the association between the -1082A/G polymorphism in the IL-10 gene and SLE.

METHODS

We searched all publications on the association between the IL-10 (-1082A/G) polymorphism and SLE in PubMed, Elsevier Science Direct, Chinese Biomedical Literature Database (CBM), Chinese National Knowledge Infrastructure (CNKI) and Wanfang (Chinese). Meta-analysis was conducted using software Stata version 10.1. Meta-odds ratios (ORs) and 95% confidence intervals (CIs) based on fixed-/random-effects models depended on Cochran's Q-statistic and I(2) values.

RESULTS

A total of 17 studies with 2396 cases and 3653 controls were included in this meta-analysis. Meta-analysis was performed for genotypes GG versus AA, GG + AG versus AA, GG versus AG + AA, and G allele versus A allele. Significant differences were found in genotype distribution between SLE and normal controls in whole-population GG versus AA (OR = 1.428, 95% CI = 1.006-2.208). Similar results were detected in the dominant genetics effect of the G allele (OR = 1.202, 95% CI = 1.030-1.403). No significant association was found in allele distribution in whole-population G versus A (OR = 1.125, 95% CI = 0.998-1.269). In subgroup analysis by ethnicity, significant association was found when GG + AG versus AA was performed in a European population (OR = 1.240, 95% CI = 1.022-1.503) and GG versus AG + AA was performed in an Asian population (OR = 3.596, 95% CI = 1.389-9.311). Significant association was found between genotype distribution in Asians (OR = 4.491, 95% CI = 1.552-13.000). Publication year was detected as the source of heterogeneity. In the stratified analysis by publication year, the pooled OR was 1.049 (95% CI = 0.940-1.171; P (heterogeneity) = 0.431; I(2) ( )= 0.4%) in subgroup 1 (publication years 1999-2004). No significant association was found between the IL-10 (-1082 G) allele and SLE in subgroup 1 (Z = 0.85, p = 0.431). In subgroup 2 (publication years 2005-2011), the pooled OR was 1.327 (95% CI = 1.125-1.565; P (heterogeneity) = 0.143; I(2) ( )= 35.8%). Significant association was found between the IL-10 (-1082 G) allele and SLE (Z = 3.36, p = 0.001).

CONCLUSIONS

This meta-analysis demonstrates the association between the IL-10 (-1082A/G) polymorphism and SLE. However, further studies are needed for a definitive conclusion.

A new technology for separation and recovery of materials from waste printed circuit boards by dissolving bromine epoxy resins using ionic liquid

Recovery of valuable materials from waste printed circuit boards (WPCBs) is quite difficult because WPCBs is a heterogeneous mixture of polymer materials, glass fibers, and metals. In this study, WPCBs was treated using ionic liquid (1-ethyl-3-methylimizadolium tetrafluoroborate [EMIM+][BF4-]). Experimental results showed that the separation of the solders went to completion, and electronic components (ECs) were removed in WPCBs when [EMIM+][BF4-] solution containing WPCBs was heated to 240 °C. Meanwhile, metallographic observations verified that the WPCBs had an initial delamination. When the temperature increased to 260 °C, the separation of the WPCBs went to completion, and coppers and glass fibers were obtained. The used [EMIM+][BF4-] was treated by water to generate a solid-liquid suspension, which was separated completely to obtain solid residues by filtration. Thermal analyses combined with infrared ray spectra (IR) observed that the solid residues were bromine epoxy resins. NMR (nuclear magnetic resonance) showed that hydrogen bond played an important role for [EMIM+][BF4-] dissolving bromine epoxy resins. This clean and non-polluting technology offers a new way to recycle valuable materials from WPCBs and prevent environmental pollution from WPCBs effectively.