Human positive coactivator 4 is a potential novel therapeutic target in non-small cell lung cancer

Transcriptional positive coactivator 4 (PC4) is a multifunctional nuclear protein that has important roles in DNA transcription, replication, repair and heterochromatinization. However, the role of PC4 in cancer remains to be clarified. Several studies propose that PC4 may act as a putative tumor suppressor. Here, we demonstrate for the first time that PC4 may represent a potential therapeutic target in non-small cell lung cancer (NSCLC). PC4 protein expression is significantly upregulated in NSCLC carcinoma tissues compared with their adjacent noncancerous counterparts as shown by immunohistochemical staining and western blotting in 104 pairs of formalin-fixed human NSCLC specimens and 6 fresh NSCLC samples. Knockdown of PC4 expression by sequence-specific small interfering RNA (siRNA) in human NSCLC cells (A549, H460 and H358) significantly inhibits the growth of cancer cells by the induction of cell cycle arrest and the increase of cell apoptosis in vitro. Interrupting the PC4 signaling pathway by injection of the PC4 siRNA liposome complex produced an effective regression of pre-established A549 cell xenografts in mice through growth inhibition and increased apoptosis. These results indicated that PC4 could be an attractive new therapeutic target for the treatment of NSCLC.

Effect of triptolide on progesterone production from cultured rat granulosa cells

Triptolide(CAS 38748-32-2), a major active component of Tripterygium wilfordii Hook F (TWHF), is known to have multiple pharmacological activities. However, studies have also shown that triptolide is highly disrupt to the reproductive system by disrupting normal steroid hormone signaling. In the present study, we investigated the effect of triptolide (5, 10, or 20 nM for 24 h) on progesterone production by rat granulosa cells. Triptolide inhibited both basal and human chorionic gonadotropin (HCG)- and 8-bromo-cAMP-stimulated progesterone production as revealed by RIA assay. Furthermore, the HCG-evoked increase in cellular cAMP content was also inhibited by triptolide, indicating that disruption of the cAMP/PKA signaling pathway may mediate the deleterious effects of triptolide on progesterone regulation. In addition, triptolide inhibited 25-OH-cholesterol-stimulated progesterone production, suggesting that activity of the P450 side chain cleavage (P450scc) enzyme was also be inhibited by triptolide. Western blot and quantitative real-time PCR (qRT-PCR) assays further revealed that triptolide decreased mRNA and protein expression of P450scc and the steroidogenic regulatory (StAR) protein in granulosa cells. In contrast, cell viability tests using 3-(4,5-dimethyl-thiazol-2-yl)-2,5- diphenyl-tetrazolium bromide (MTT) indicated that triptolide did not cause measurable cell death at doses that suppressed steroidogenesis. The reproductive toxicity of triptolide may be caused by disruption of cAMP/PKA-mediated expression of a number of progesterone synthesis enzymes or regulatory proteins, leading to reduced progesterone synthesis and reproductive dysfunction.

Competing ferri- and antiferromagnetic phases in geometrically frustrated LuFe2O4

We present a detailed study of magnetism in LuFe(2)O(4), combining magnetization measurements with neutron and soft x-ray diffraction. The magnetic phase diagram in the vicinity of T(N) involves a metamagnetic transition separating an antiferro- and a ferrimagnetic phase. For both phases the spin structure is refined by neutron diffraction. Observed diffuse magnetic scattering far above T(N) is explained in terms of near degeneracy of the magnetic phases.

Abnormal epigenetic modifications in peripheral blood mononuclear cells from patients with alopecia areata

BACKGROUND

Alopecia areata (AA) is a hair loss disease caused by T-cell-mediated autoimmune reactions against anagen-stage hair follicles. Although the exact aetiology is poorly understood, there is evidence to suggest that both genetic and environmental factors are involved in AA pathogenesis.

OBJECTIVES

To analyse DNA methylation and histone modification patterns in peripheral blood mononuclear cells (PBMCs) of patients with AA.

METHODS

PBMC samples were obtained from 25 patients with AA and 20 healthy controls. Global DNA methylcytosine levels, as well as histone acetylation and methylation levels, were measured by enzyme-linked immunosorbent assay. mRNA expression levels were determined using real-time quantitative reverse transcription-polymerase chain reaction.

RESULTS

Genomic DNA methylation in PBMCs of patients with AA was increased relative to controls. DNMT1, MBD1 and MBD4 expression levels were significantly higher in AA PBMCs than in controls, and DNMT1 transcription levels positively correlated with global DNA methylation levels in patient samples. Histone H3 acetylation was significantly increased and histone H3 lysine 4 methylation was significantly decreased in patient PBMCs compared with healthy controls. Histone H3 acetylation levels were positively correlated with AA disease severity, and with RANTES (CCL5) mRNA expression in PBMCs of patients with AA. These changes were accompanied by increased p300 (EP300), histone deacetylase 1 (HDAC1), myeloid/lymphoid or mixed lineage leukemia (MLL), SET7/9 (SETD7), G9A (EHMT2), JMJD2C (KDM4C) and JARID1A (KDM5A) expression, as well as reduced HDAC2, HDAC7, LSD1 (KDM1A), JMJD2A (KDM4A) and JMJD2B (KDM4B) expression.

CONCLUSIONS

DNA methylation and histone modification status are altered in PBMCs of patients with AA, possibly due to the deregulation of epigenetic regulatory genes. These changes may contribute to the activation of pathological immune responses in AA.

P3-16-08: A Phase 2, Randomized Open-Label Study of Iniparib, Administered Either Weekly or Twice-Weekly in Combination with Gemcitabine Plus Carboplatin in Patients with mTNBC

Background

Iniparib (BSI-201) is an investigational anticancer agent whose precise mechanism of action is under active investigation. In breast cancer cell lines and xenograft models of triple-negative breast cancer (TNBC), iniparib exhibits anti-proliferative activity and potentiates the cell cycle effects of some DNA damaging agents. In a randomized, open-label phase 2 study in pts with metastatic TNBC (mTNBC), iniparib combined with gemcitabine (G) and carboplatin (C) (GC) improved efficacy outcomes compared with GC alone. A confirmatory phase 3 study with GCI failed to meet pre-specified criteria for PFS and OS; however, an exploratory subset analysis demonstrated a potential benefit amongst 2nd/3rd line pts (O'Shaughnessy et al. ASCO 2011). Here we report results of a randomized phase 2 study (NCT01045304) in pts with mTNBC, which assesses efficacy and pharmacokinetics (PK) of iniparib administered either biw or qw in combination with GC.

Patients and methods: Eligible pts (N=163; median age 49 yrs) had documented and measurable TNBC, ECOG PS 0–1, normal organ/marrow function, and had received ≤2 prior chemotherapy (CT) regimens for metastatic disease. Pts were randomized (1:1) to receive G (1,000 mg/m2, IV, d 1, 8) plus C (AUC 2, IV, d 1, 8) and iniparib either biw (5.6 mg/kg, IV d 1,4,8,11) or qw (11.2 mg/kg, IV d 1,8) on a 21 d cycle. Pts were stratified according to prior CT for mTNBC (0 vs. 1–2). The primary efficacy endpoint was overall response rate (ORR; CR + PR); secondary endpoints included: clinical benefit rate (CBR; CR + PR + SD for 24 weeks), PFS, OS and PK.

Results: At the time of analysis, 23% of patients were still on treatment. The median number of cycles administered per patient was 6 in both arms; exposure to iniparib was identical. Safety data are not fully validated. All pts experienced at least 1 treatment emergent adverse event (TEAE). Grade (Gr) ≥3 TEAEs occurred in 94% and 85% of pts in the biw and qw arms, respectively. TEAEs Gr ≥3 occurring in ≥5% of pts regardless of relationship to study drug (biw vs qw) are as follows: blood and lymphatic 71% vs 67%; hepatobiliary 7.5% vs 9.8%; asthenia/fatigue 7.5% vs 11%; GI 8.8% vs 8.5%; infections 7.5% vs 3.7%; respiratory, thoracic and mediastinal 5% vs 8.5%, metabolism and nutrition 4% vs 6%. For response data see table.

N-cadherin haploinsufficiency increases survival in a mouse model of pancreatic cancer

Pancreatic ductal adenocarcinoma (PDA) is often detected at a late stage, hence the identification of new therapies that have potential to block tumor progression is critical for this lethal disease. N-cadherin upregulation has been observed in many cancers including PDA, however, a causal role for this cell adhesion receptor in disease progression has yet to be defined. The concomitant expression of oncogenic Kras(G12D) and mutant p53 (Trp53(R172H)) in the murine pancreas results in metastatic PDA that recapitulates the cognate features of human pancreatic cancer providing an excellent animal model to identify genes required for tumor progression. Here we determine the consequences of genetically manipulating N-cadherin expression in a mouse model of PDA. Remarkably, mice with reduced N-cadherin expression (that is, Ncad(-/+)) survived 25% longer (177 vs 142 days, P<0.05) than animals expressing two wild-type N-cadherin (Cdh2) alleles. The survival benefit is likely due to a cumulative effect of N-cadherin's role in different aspects of tumorigenesis including tumor-cell survival, growth, migration and invasion. Interestingly, reduced hedgehog signaling may contribute to the better prognosis for the Ncad(-/+) mice. Moreover, the matrix metalloproteinase MMP-7, associated with poor prognosis in PDA, was reduced in Ncad(-/+) tumors. Finally, Ncad(-/+) tumor cells exhibited decreased FGF-stimulated ERK1/2 activation consistent with N-cadherin's ability to promote FGFR signaling. These data support a critical role for N-cadherin in PDA and its potential prognostic value. Additionally, this study provides in vivo genetic evidence that the cell-surface protein N-cadherin represents a promising therapeutic target for the treatment of pancreatic cancer.

Implications of QRS duration in dogs with pacing-induced heart failure

The objective of this study was to find out the implication of QRS duration in dogs with rapid pacing-induced heart failure. Sixteen Beagle dogs were implanted with transvenous cardiac pacemakers and underwent rapid right ventricular pacing for 3 weeks at 260 bpm to induce heart failure. Dogs were divided into two groups according to the QRS duration: 9 with normal QRS duration (<100 ms) and 7 with prolonged QRS duration (≥100 ms). Cardiac systolic function and size was analyzed by real time 3-dimensional echocardiography and left ventricular dyssynchrony was assessed by speckle tracking strain imaging. Congestive heart failure developed 3 weeks after rapid right ventricular pacing. Dogs with prolonged QRS duration showed more extensive radial strain and circumferential strain dyssynchrony than dogs with normal QRS duration. At the end of 4-week recovery, greater improvement of left ventricular ejection fraction and left ventricular end-systolic volume was detected in dogs with normal QRS duration. The findings suggested that left ventricular dyssynchrony, indicated by a prolonged QRS duration, predicted an unsatisfying recovery in dogs with rapid pacing-induced heart failure. QRS duration had the potential to be a prognostic indicator for dogs with heart failure.

Circulating obestatin concentration is lowered by insulin in rats

Circulating obestatin is lowered by food intake, but factors involved in obestatin regulation remain unclear. The aim of this study was to determine whether intravenous glucose or insulin infusion lowers obestatin. Rats were infused over 3 h with either A. saline (controls); B. dextrose to steady state blood glucose ~16.7 mM, or C. insulin 7.5 mU/kg.min, plus dextrose as needed to clamp to euglycemic basal concentrations. During 3 h of infusion, group B had significantly greater (P<0.01) glucose, 18.75±1.27 mM, than groups A (6.10±0.33 mM) or C (6.19±0.18 mM). Groups B and C had hyperinsulinemia at the end of the 3 h infusion (1.02±0.03 ng/ml, 1.07±0.02 ng/ml) compared with saline-infused (0.38±0.01 ng/ml, P<0.01). Obestatin concentrations were significantly reduced (P<0.01) in both hyperinsulinemic groups and (B=0.95±0.06 ng/ml; C=0.87±0.04 ng/ml) versus controls (1.56±0.13 ng/ml). These data suggest that insulin can decrease the plasma obestatin levels.

Subclinical hypothyroidism and its association with lupus nephritis: a case control study in a large cohort of Chinese systemic lupus erythematosus patients

The aim of this study was to evaluate the prevalence of thyroid diseases in Chinese systemic lupus erythematosus (SLE) patients and the relevance of subclinical hypothyroidism (SCH) with lupus nephritis (LN). A large cohort of 1006 SLE patients was retrospectively analyzed. The prevalence of autoimmune thyroid disease was 2.78%, clinical hypothyroidism 1.69%, subclinical hypothyroidism 10.04%, central hypothyroidism 1.29%, hyperthyroidism 1.19%, euthyroid sick syndrome (ESS) 9.54%, and nodules 1.09%, respectively. Compared with the prevalence of thyroid abnormalities in the general Chinese population (0.91–6.05%), SCH was much higher (10.04%) in this study. In addition, SCH was more frequent in patients with LN (13.4%) than those without LN (7.3%, p = 0.001). Case control study was performed to explore the relative risk factors of SCH. In multiple logistic regression models, 24 h urine protein and estimated glomerular filtration rate (eGFR) were retained as independent correlates of SCH after adjusting for demographic variables, risk factors, and other potential confounders. The results of the present study suggest that SCH is a common complication in SLE patients, and closely related with LN.

Degradation of MEH-PPV due to Oxygen/Moisture Traps through C-V Analysis and Attenuated Total Reflection IR Spectroscopy

We present the studying of oxygen and moisture traps in MEH-PPV through the MIS Capacitance – Voltage (C-V) analysis, and the Attenuated Total Reflection Infrared (ATR IR) spectroscopy technique. The presence of oxygen studied by ATR IR has also been verified by optical images from high resolution optical microscope. In quasi-static C-V measurements of the MIS (Al/MEH-PPV/p-Si) capacitors made, an extension of the weak inversion region was measured before strong inversion, which becomes more pronounced with aging. This increase in the weak inversion region is attributed to electron trapping by oxygen to form negative ions in the MEH-PPV layer. ATR IR spectroscopy shows the formation of carbonyl peak at 1651 cm−1 with aging, which is due to the presence of oxygen. Both the C-V analysis and Attenuated Total Reflection IR Spectroscopy are powerful tools for investigating the degradation of MEH-PPV polymer.

Impact of surgical ventricular restoration on ventricular shape, wall stress, and function in heart failure patients

Surgical ventricular restoration (SVR) was designed to treat patients with aneurysms or large akinetic walls and dilated ventricles. Yet, crucial aspects essential to the efficacy of this procedure like optimal shape and size of the left ventricle (LV) are still debatable. The objective of this study is to quantify the efficacy of SVR based on LV regional shape in terms of curvedness, wall stress, and ventricular systolic function. A total of 40 patients underwent magnetic resonance imaging (MRI) before and after SVR. Both short-axis and long-axis MRI were used to reconstruct end-diastolic and end-systolic three-dimensional LV geometry. The regional shape in terms of surface curvedness, wall thickness, and wall stress indexes were determined for the entire LV. The infarct, border, and remote zones were defined in terms of end-diastolic wall thickness. The LV global systolic function in terms of global ejection fraction, the ratio between stroke work (SW) and end-diastolic volume (SW/EDV), the maximal rate of change of pressure-normalized stress (dσ*/dt(max)), and the regional function in terms of surface area change were examined. The LV end-diastolic and end-systolic volumes were significantly reduced, and global systolic function was improved in ejection fraction, SW/EDV, and dσ*/dt(max). In addition, the end-diastolic and end-systolic stresses in all zones were reduced. Although there was a slight increase in regional curvedness and surface area change in each zone, the change was not significant. Also, while SVR reduced LV wall stress with increased global LV systolic function, regional LV shape and function did not significantly improve.

Involvement of T helper type 17 and regulatory T cell activity in tumour immunology of bladder carcinoma

T helper type 17 (Th17) and regulatory T cells (T(reg) ) play an important role in the pathogenesis of inflammation and autoimmune disorders. Recent studies have suggested that they also had an impact on tumour immunology. However, the relationship between Th17 and T(reg) cells in the pathogenesis of bladder carcinoma is still unclear. Flow cytometry was used to analyse the numbers, phenotype and cytokine production of Th17 cells in peripheral blood and tumour tissue from bladder carcinoma patients, in parallel with analysis of T(reg) cells. The suppressor capacity of T(reg) and the potential effects of interleukin (IL)-2 on the differentiation of Th17 and T(reg) cells in vitro were studied in a T cell stimulation and suppression assays. The results were as follows: Th17 cells were enriched in the tumours of patients with bladder carcinoma compared with the peripheral blood of patients and controls; patients with bladder carcinoma had a higher proportion of T(reg) cells in peripheral blood compared with healthy controls and nearly all patients examined showed a relative enrichment of tumour-infiltrating T(reg) with respect to peripheral blood; there appeared to be an inverse relationship between tumour-infiltrating Th17 and T(reg) cells; IL-2 could convert tumour-infiltrating T(reg) cells cultured in the presence of the autologous irradiated CD3(-) fraction into Th17 cells, down-regulate forkhead box P2 expression and suppressive capacity of T(reg) cells. This study is the first to define the frequency and characteristics of Th17 cells in bladder carcinoma. We suggest that the balance between Th17 and T(reg) cells may be involved in the development or progression of bladder carcinoma.