Transcription and translation of human F11R gene are required for an initial step of atherogenesis induced by inflammatory cytokines

Background

Several proteins that promote angiogenesis are overexpressed in hepatocellular carcinoma (HCC) and have been implicated in disease pathogenesis. Sunitinib has antiangiogenic activity and is an oral multitargeted inhibitor of vascular endothelial growth factor receptors (VEGFRs)-1, -2, and -3, platelet-derived growth factor receptors (PDGFRs)-α and -β, stem-cell factor receptor (KIT), and other tyrosine kinases. In a phase II study of sunitinib in advanced HCC, we evaluated the plasma pharmacodynamics of five proteins related to the mechanism of action of sunitinib and explored potential correlations with clinical outcome.

Methods

Patients with advanced HCC received a starting dose of sunitinib 50 mg/day administered orally for 4 weeks on treatment, followed by 2 weeks off treatment. Plasma samples from 37 patients were obtained at baseline and during treatment and were analyzed for vascular endothelial growth factor (VEGF)-A, VEGF-C, soluble VEGFR-2 (sVEGFR-2), soluble VEGFR-3 (sVEGFR-3), and soluble KIT (sKIT).

Results

At the end of the first sunitinib treatment cycle, plasma VEGF-A levels were significantly increased relative to baseline, while levels of plasma VEGF-C, sVEGFR-2, sVEGFR-3, and sKIT were significantly decreased. Changes from baseline in VEGF-A, sVEGFR-2, and sVEGFR-3, but not VEGF-C or sKIT, were partially or completely reversed during the first 2-week off-treatment period. High levels of VEGF-C at baseline were significantly associated with Response Evaluation Criteria in Solid Tumors (RECIST)-defined disease control, prolonged time to tumor progression (TTP), and prolonged overall survival (OS). Baseline VEGF-C levels were an independent predictor of TTP by multivariate analysis. Changes from baseline in VEGF-A and sKIT at cycle 1 day 14 or cycle 2 day 28, and change in VEGF-C at the end of the first off-treatment period, were significantly associated with both TTP and OS, while change in sVEGFR-2 at cycle 1 day 28 was an independent predictor of OS.

Conclusions

Baseline plasma VEGF-C levels predicted disease control (based on RECIST) and were positively associated with both TTP and OS in this exploratory analysis, suggesting that this VEGF family member may have utility in predicting clinical outcome in patients with HCC who receive sunitinib.

Trial registration

ClinicalTrials.gov: NCT00247676     

The VEGF- and PDGF-family of angiogenic markers have prognostic impact in soft tissue sarcomas arising in the extremities and trunk

Background

Soft-tissue sarcomas are rare malignant tumors of mesenchymal lineage that can arise in any part of the body. Prognosis, and hence also treatment may vary according to histologic subtype and localization. Angiogenesis is the process of forming new blood vessels from pre-existing ones. The deregulation of this process is thought to be an important step in malignant transformation. This study investigates the prognostic impact of platelet derived growth factor- (PDGF), vascular endothelial growth factor- (VEGF) and fibroblast growth factor (FGF) families in soft-tissue sarcomas of the extremities & trunk (ET) and visceral & retroperitoneal (VR) locations.

Methods

Tumor samples from 181 patients (115 ET and 66 VR) with resected soft tissue sarcomas were collected and tissue microarrays were constructed. Immunohistochemistry was used to evaluate angiogenic marker expression. Recurrence-free survival (RFS), metastasis-free survival (MFS) and disease-specific survival (DSS) were used as endpoints in prognostic impact assessment.

Results

In univariate analyses, almost all investigated angiogenic markers had prognostic impact in the ET group. In contrast, only FGFR-1 showed any significant prognostic impact in the VR group. In the multivariate analyses, PDGF-D (HR?=?1.863, 95% CI?=?1.057-3.283, P?=?0.031), VEGFR-1 (HR?=?2.106, 95% CI?=?1.038-4.272, P?=?0.039) and VEGF-A (HR 2.095, 95% CI 1.028-4.271, P?=?0.042) were independent negative prognosticators for DSS, MFS and RFS, respectively, in the ET group. FGFR-1 was an independent positive prognosticator for DSS (HR?=?0.243, 95% CI?=?0.095-0.618, P?=?0.003) in the VR group.

Conclusions

Angiogenic molecules from the PDGF and VEGF families have prognostic impact in soft-tissue sarcomas arising in the ET, but not in VR locations. In the latter histological grade and resection margins are the most important prognostic factors.     

Negative enrichment by immunomagnetic nanobeads for unbiased characterization of circulating tumor cells from peripheral blood of cancer patients

Background

Non-gastrointestinal stromal tumor soft-tissue sarcomas (non-GIST STSs) constitute a heterogeneous group of tumors with poor prognosis. Fibroblast growth factor 2 (FGF2) and fibroblast growth factor receptor-1 (FGFR-1), in close interplay with platelet-derived growth factor-B (PDGF-B) and vascular endothelial growth factor receptor-3 (VEGFR-3), are strongly involved in angiogenesis. This study investigates the prognostic impact of FGF2 and FGFR-1 and explores the impact of their co-expression with PDGF-B and VEGFR-3 in widely resected tumors from non-GIST STS patients.

Methods

Tumor samples from 108 non-GIST STS patients were obtained and tissue microarrays were constructed for each specimen. Immunohistochemistry was used to evaluate the expressions of FGF-2, FGFR-1, PDGF-B and VEGFR-3.

Results

In the multivariate analysis, high expression of FGF2 (P = 0.024, HR = 2.2, 95% CI 1.1-4.4) and the co-expressions of FGF2 & PDGF-B (overall; P = 0.007, intermediate; P = 0.013, HR = 3.6, 95% CI = 1.3-9.7, high; P = 0.002, HR = 6.0, 95% CI = 2.0-18.1) and FGF2 & VEGFR-3 (overall; P = 0.050, intermediate; P = 0.058, HR = 2.0, 95% CI = 0.98-4.1, high; P = 0.028, HR = 2.6, 95% CI = 1.1-6.0) were significant independent prognostic indicators of poor disease-specific survival.

Conclusion

FGF2, alone or in co-expression with PDGF-B and VEGFR-3, is a significant independent negative prognosticator in widely resected non-GIST STS patients.     

ERCC1 expression and tumor regression predict survival in esophageal squamous cell carcinoma patients receiving combined trimodality therapy

Purpose

Combined trimodality therapy with neoadjuvant chemoradiation followed by surgery has shown promising results for locally advanced operable esophageal cancer. DNA repair proteins may affect treatment efficacy through repairing DNA damage induced by chemotherapy and radiation therapy. We evaluated the associations of XRCC1, ERCC1 and MGMT expression with histopathologic response and survival in patients with locally advanced operable esophageal squamous cell carcinoma (ESCC) who received neoadjuvant chemoradiation.

Methods

Paraffin-embedded pre-treatment tissue samples, collected by endoscopic biopsy from patients treated with cisplatin-based neoadjuvant chemoradiation followed by surgery, were immunohistochemically stained for XRCC1, ERCC1 and MGMT expression.

Results

Of the 44 patients, major histopathologic response was noted in 26 (59.1%) patients. 68.8% of patients with ERCC1-negative tumors had major histopathologic response, compared to 53.6% of those who expressed positive ERCC1, though the difference was not statistically significant (P = 0.361). The patients with ERCC1-negative tumor presented much better overall survival than those positive for ERCC1 expression (P = 0.018). Patients with major histopathologic response had a 3-year survival rate of 96.2% versus those with minor response, with a 3-year survival rate of 41.5% (P = 0.000). Multivariate analysis showed that ERCC1 expression and histopathologic response were independent predictive factors of overall survival in patients with locally advanced operable ESCC receiving neoadjuvant chemoradiation.

Conclusion

Patients with ERCC1-negative tumors show a benefit from neoadjuvant chemoradiation, ERCC1 expression and tumor regression are useful predictive markers in patients with locally advanced operable ESCC receiving neoadjuvant chemoradiation followed by surgery.     

Acute low-load resistance exercise with and without blood flow restriction increased protein signalling and number of satellite cells in human skeletal muscle

Purpose

To investigate hypertrophic signalling after a single bout of low-load resistance exercise with and without blood flow restriction (BFR).

Methods

Seven subjects performed unilateral knee extensions at 30 % of their one repetition maximum. The subjects performed five sets to failure with BFR on one leg, and then repeated the same amount of work with the other leg without BFR. Biopsies were obtained from m. vastus lateralis before and 1, 24 and 48 h after exercise.

Results

At 1-h post-exercise, phosphorylation of p70S6K^Thr389 and p38MAPK^{Thr180/Tyr182} was elevated in the BFR leg, but not in the free-flow leg. Phospho-p70S6K^Thr389 was elevated three- to fourfold in both legs at 24-h post-exercise, but back to baseline at 48 h. The number of visible satellite cells (SCs) per muscle fibre was increased for all post-exercise time points and in both legs (33–53 %). The proportion of SCs with cytoplasmic extensions was elevated at 1-h post in the BFR leg and the number of SCs positive for myogenin and/or MyoD was increased at 1- and 24-h post-exercise for both legs combined.

Conclusion

Acute low-load resistance exercise with BFR resulted in early (1 h) and late (24 h) enhancement of phospho-p70S6K^Thr389, an early response of p38MAPK, and an increased number of SCs per muscle fibre. Enhanced phospho-p70S6K^Thr389 at 24-h post-exercise and increases in SC numbers were seen also in the free-flow leg. Implications of these findings for the hypertrophic effects of fatiguing low-load resistance exercise with and without BFR are discussed.     

Time-course of sFlt-1 and VEGF-A release in neutropenic patients with sepsis and septic shock: a prospective study

Background  

Septic shock is the most feared complication of chemotherapy-induced febrile neutropenia. So far, there are no robust biomarkers that can stratify patients to the risk of sepsis complications. The VEGF-A axis is involved in the control of microvascular permeability and has been involved in the pathogenesis of conditions associated with endothelial barrier disruption such as sepsis. sFlt-1 is a soluble variant of the VEGF-A receptor VEGFR-1 that acts as a decoy receptor down-regulating the effects of VEGF-A. In animal models of sepsis, sFlt-1 was capable to block the barrier-breaking negative effects of VEGF-A and to significantly decrease mortality. In non-neutropenic patients, sFlt-1 has been shown to be a promising biomarker for sepsis severity.     

The cytoprotective drug amifostine modifies both expression and activity of the pro-angiogenic factor VEGF-A

Background

Amifostine (WR-2721, delivered as Ethyol^®) is a phosphorylated aminothiol compound clinically used in addition to cis-platinum to reduce the toxic side effects of therapeutic treatment on normal cells without reducing their efficacy on tumour cells. Its mechanism of action is attributed to the free radical scavenging properties of its active dephosphorylated metabolite WR-1065. However, amifostine has also been described as a potent hypoxia-mimetic compound and as a strong p53 inducer; both effects are known to potently modulate vascular endothelial growth factor (VEGF-A) expression. The angiogenic properties of this drug have not been clearly defined.

Methods

Cancer cell lines and endothelial cells were used in culture and treated with Amifostine in order to study (i) the expression of angiogenesis related genes and proteins and (ii) the effects of the drug on VEGF-A induced in vitro angiogenesis.

Results

We demonstrated that the treatment of several human cancer cell lines with therapeutical doses of WR-1065 led to a strong induction of different VEGF-A mRNA isoforms independently of HIF-1α. VEGF-A induction by WR-1065 depends on the activation of the eIF2alpha/ATF4 pathway. This up-regulation of VEGF-A mRNA was accompanied by an increased secretion of VEGF-A proteins fully active in stimulating vascular endothelial cells (EC). Nevertheless, direct treatment of EC with amifostine impaired their ability to respond to exogenous VEGF-A, an effect that correlated to the down-regulation of VEGFR-2 expression, to the reduction in cell surface binding of VEGF-A and to the decreased phosphorylation of the downstream p42/44 kinases.

Conclusions

Taken together, our results indicate that amifostine treatment modulates tumour angiogenesis by two apparently opposite mechanisms - the increased VEGF-A expression by tumour cells and the inhibition of EC capacity to respond to VEGF-A stimulation.

     

Loss of PTEN in high grade advanced stage triple negative breast ductal cancers in African American women

Introduction

PTEN is a tumor suppressor gene that inhibits cell proliferation by inhibiting the phosphoinositide 3-kinase (PI3?K) signaling pathway. The significance of PTEN mutations resulting in variable PTEN expression and their impact on prognosis of breast cancer is not well established. The objective of our study was to correlate the immunohistochemical expression of PTEN in the four major subtypes of breast carcinoma (Luminal A, Luminal B, HER2 positive, and Triple Negative) in a population of 202 African-American (AA) females with other clinicopathological factors.

PTEN Is a Target of Chromosome 10q Loss in Anaplastic Oligodendrogliomas and PTEN Alterations Are Associated with Poor Prognosis

Allelic loss of 10q is a common genetic event in malignant gliomas, with three 10q tumor suppressor genes, ERCC6, PTEN, and DMBT1, putatively implicated in the most common type of malignant glioma, glioblastoma. Anaplastic oligodendroglioma, another type of malignant glioma, provides a unique opportunity to study the relevance of particular genetic alterations to chemosensitivity and survival. We therefore analyzed these three genes in 72 anaplastic oligodendrogliomas. Deletion mapping demonstrated 10q loss in 14 of 67 informative cases, with the PTEN and DMBT1 regions involved in all deletions but with the ERCC6 locus spared in two cases. Seven tumors had PTEN gene alterations; two had homozygous DMBT1 deletions, but at least one reflected unmasking of a germline DMBT1 deletion. No mutations were found in ERCC6 exon 2. Chemotherapeutic response occurred in two of the seven tumors with PTEN alterations, but with unexpected short survival times. PTEN gene alterations were not associated with poor therapeutic response in multivariate analysis, but were independently predictive of poor prognosis even after multivariate adjustment for both 10q and 1p loss. In anaplastic oligodendroglioma, therefore, PTEN is a target of 10q loss, and PTEN alterations are associated with poor prognosis, even in chemosensitive cases.     

A VEGFR-3 Antagonist Increases IFN-γ Expression on Low Functioning NK Cells in Acute Myeloid Leukemia

Purpose

Although the importance of vascular endothelial growth factor receptor (VEGFR)-3 has been demonstrated in acute myeloid leukemia (AML), the role of VEGFR-3 in functioning natural killer (NK) cells remains largely unexplored. NK cells can destroy cancer cells by releasing the cytokine interferon (IFN)-γ, but NK cells in AML patients (AML NK cells) have low cytolytic activity. In the present study, we investigated whether lymphatic markers including VEGFR-3 are expressed on low-functioning AML NK cells and VEGFR-3 antagonist can restore expression of IFN-γ in NK cells.

Methods

Samples from 67 de novo AML patients and 34 healthy donors were analyzed for lymphatic markers expression using RT-PCR, flow cytometry, and immunostaining. For the cytotoxicity assays, K562 cells and AML NK cells were used as target and effector cells, respectively. To block VEGFR-3, MAZ51 was added to NK cells, which were then subjected to FACS analysis.

Results

Compared with NK cells from healthy donors (healthy NK cells), AML NK cells exhibited higher levels of VEGFR-3 and lower expression of IFN-γ. VEGFR-3-expressing AML NK cells were less potent than healthy NK cells in terms of killing K562 cells. The level of IFN-γ in AML NK cells was increased by VEGFR-3 antagonist treatment, indicating the functional relevance of VEGFR-3 in IFN-γ-secreting NK cells.

Conclusion

Collectively, our data suggest a relationship between VEGFR-3 and IFN-γ expression in NK cells and raise the possibility of advanced therapeutic approaches involving VEGFR-3 antagonist treatment prior to NK immune cell therapy in AML.     

Kisspeptin and GPR54 immunoreactivity in a cohort of 518 patients defines favourable prognosis and clear cell subtype in ovarian carcinoma

Background

Kisspeptins and their G-protein coupled receptor, GPR54 are required for GnRH release and have been associated with anti-metastatic tumour cell behaviour in model systems. The latter might suggest that their overexpression would be associated with a better prognosis in cancer. However, kisspeptin/GPR54 interactions (autocrine, paracrine, and/or endocrine) could also impact tumour behaviour in a negative manner. Here, for the first time, we associate the immunoreactivity of the kisspeptin/GPR54 ligand-receptor pair with favourable prognosis in a large cohort of ovarian carcinomas.

Methods

Immunohistochemical analysis for kisspeptin and GPR54 was performed on a tissue microarray (TMA) consisting of 518 early stage ovarian carcinomas, all with linked clinical outcome data. The TMA was scored using a staining intensity scale of 0 (negative), +1 (mild-moderate), and +2 (strong). Strong staining cases were considered either kisspeptin or GPR54 positive and designated as 1, while all other cases were considered negative and designated 0. All statistical analysis was conducted using two-sided tests and a p value equal to or less than 0.05 was considered significant.

Results

Kisspeptin and GPR54 immunoreactive cases show a favourable prognosis in univariable disease specific survival (p = 0.0023, p = 0.0092), as well as in overall survival (p = 0.0006, p = 0.0002). Furthermore, kisspeptin is an independent marker for favourable prognosis as determined by multivariable disease specific (p = 0.0046) and overall survival analysis (p = 0.0170), while GPR54 is an independent marker for overall survival only (p = 0.0303). Both kisspeptin positive and GPR54 positive cases are strongly associated with the ovarian carcinoma clear cell subtype (p < 0.0001, p < 0.0001), and GPR54 is significantly associated with favourable prognosis in overall survival within the clear cell subtype (p = 0.0102).

Conclusion

Kisspeptin and GPR54 immunoreactivity are significantly associated with favourable prognosis in both disease specific and overall survival, as well as being significantly associated with the clear cell ovarian carcinoma subtype, thereby creating the first independent prognostic biomarkers specific for ovarian clear cell carcinomas.     

人结直肠癌组织中表皮生长因子受体1与Fascin-1蛋白表达的相关性及其临床意义

目的 探讨人结直肠癌组织中表皮生长因子受体1(EGFR)与Fascin-1蛋白表达的关系及其临床意义。方法 回顾性收集2008年1月-2010年12月东阳市人民医院病理科结直肠癌石蜡标本258例和同时切除的正常结直肠组织石蜡标本72例。采用免疫组织化学EnVision法检测并比较直肠癌组织和正常结直肠组织中EGFR和Fascin-1蛋白的表达;分析结直肠癌中Fascin-1蛋白表达与结直肠癌患者临床病理特征、EGFR的关系,以及EGFR和Fascin-1蛋白的表达与患者的预后生存情况的关系。结果 (1)结直肠癌组织中Fascin-1蛋白的阳性率为38.0%(98/258),高于正常结直肠组织的阳性率0.0%(0/72),差异有统计学意义(χ²=38.901,P＜0.01)。(2)女性、结肠及低分化的结直肠癌患者中Fascin-1蛋白的阳性率高于男性、直肠及高-中分化患者(χ²=4.256、20.085、8.471,P值均＜0.05)。(3)在EGFR阳性结直肠癌患者的Fascin-1蛋白阳性表达率(42.9%,91/212)较EGFR阴性病例(15.2%,7/46)高,差异有统计学意义(χ²=12.318, P＜0.01);Spearman相关分析显示,结直肠癌组织中EGFR和Fascin-1蛋白表达呈正相关(r_s=0.219,P＜0.01)。(4)194例获得随访的结直肠癌患者5年总生存率为73.2%(142/194),5年无复发生存率为65.5%(127/194)。其中EGFR和Fascin-1均阳性患者的5年平均总生存期及5年总生存率(47.8个月、64.7%)低于非均阳性患者(54.4个月、77.8%),差异有统计学意义(χ²=5.039, P＜0.05)。结论 结直肠癌中EGFR与Fascin-1蛋白的表达呈正相关,二者同时表达与患者预后不良有关。     

Pancreatic head carcinoma and vascular endothelial growth factor (VEGF-A) concentration in portal blood: its association with cancer grade,tumor size and probably poor prognosis

Introduction

Vascular endothelial growth factor (VEGF) is overexpressed in pancreatic cancer. Although VEGF has been shown to be a probable marker for poor prognosis, the VEGF concentration in portal blood has not yet been clinically reported in pancreatic ductal adenocarcinoma (PDAC). The aim of the study was to measure VEGF-A portal blood concentration in patients with PDAC and to evaluate its performance as a prognostic marker.

Material and methods

Thirty-six consecutive patients out of 57 operated on for pancreatic head lesion with pathologically verified diagnosis of PDAC were enrolled in this study. We evaluated the VEGF concentration in portal blood samples obtained intraoperatively and associated their values with tumor size, stage, grade and survival.

Results

The portal VEGF-A concentration was associated with tumor grade (G1: 80.52 ±43.05 vs. G2: 185.39 ±134.98, p = 0.006, G2: 185.39 ±134.98 vs. G3: 356.46 ±229.12, p = 0.08), and there was a positive correlation with tumor size (r = 0.42, p < 0.05). In the multivariate regression analysis high levels of VEGF-A were not correlated with poor survival (HR = 5.22, 95% CI = –0.6457 to 3.9513, p = 0.19).

Conclusions

The portal VEGF-A concentration is associated with tumor grade and size. The correlation of portal VEGF-A with poor survival is not clear and needs further investigation.     

Vascular endothelial growth factor ligands and receptors that regulate human cytotrophoblast survival are dysregulated in severe preeclampsia and hemolysis, elevated liver enzymes, and low platelets syndrome

Human placental development combines elements of tumorigenesis and vasculogenesis. The organ's specialized epithelial cells, termed cytotrophoblasts, invade the uterus where they reside in the interstitial compartment. They also line uterine arteries and veins. During invasion, ectodermally derived cytotrophoblasts undergo pseudovasculogenesis, switching their adhesion molecule repertoire to mimic that of vascular cells. Failures in this transformation accompany the pregnancy complication preeclampsia. Here, we used a combination of in situ and in vitro analyses to characterize the cell's expression of vascular endothelial growth factor (VEGF) family ligands and receptors, key regulators of conventional vasculogenesis and angiogenesis. Cytotrophoblast differentiation and invasion during the first and second trimesters of pregnancy were associated with down-regulation of VEGF receptor (VEGFR)-2. Invasive cytotrophoblasts in early gestation expressed VEGF-A, VEGF-C, placental growth factor (PlGF), VEGFR-1, and VEGFR-3 and, at term, VEGF-A, PlGF, and VEGFR-1. In vitro the cells incorporated VEGF-A into the surrounding extracellular matrix; PlGF was secreted. We also found that cytotrophoblasts responded to the VEGF ligands they produced. Blocking ligand binding significantly decreased their expression of integrin alpha1, an adhesion molecule highly expressed by endovascular cytotrophoblasts, and increased apoptosis. In severe preeclampsia and hemolysis, elevated liver enzymes, and low platelets syndrome, immunolocalization on tissue sections showed that cytotrophoblast VEGF-A and VEGFR-1 staining decreased; staining for PlGF was unaffected. Cytotrophoblast secretion of the soluble form of VEGFR-1 in vitro also increased. Together, the results of this study showed that VEGF family members regulate cytotrophoblast survival and that expression of a subset of family members is dysregulated in severe forms of preeclampsia.     

胃癌中survivin、PTEN、cyclinD1和p53基因的表达及其相关性

目的　探讨survivin基因表达与胃癌生物学行为及PTEN、cyclinD1、p5 3和凋亡指数 (AI)的相关性。 方法　用免疫组化EnVision法检测 15 6例胃癌组织、4 6例正常胃黏膜和 4 6例癌旁不典型增生组织中survivin、PTEN、cyclinD1和 p5 3的表达以及AI。结果　survivin、PTEN、cyclinD1和p5 3的阳性检测率分别为 6 5 %、4 1%、6 1%和 5 8%。survivin未见核内表达。survivin、cyclinD1和 p5 3表达与胃癌的组织学类型相关 (P <0 0 1,P <0 0 5和P <0 0 1) ;survivin和cyclinD1表达与胃癌的浸润深度相关 (P <0 0 1和P <0 0 5 ) ;4种基因蛋白表达均与淋巴结转移相关 ,survivin的表达与p5 3和cyclin阳性表达呈正相关 ,与PTEN的阳性表达呈负相关 ;survivin、p5 3和cyclinD1高表达均有患者术后 <3年生存期相关 (P <0 0 5 ,P <0 0 1和P<0 0 1) ;survivin阳性组的平均AI为 0 6 1,明显低于survivin阴性组 (P <0 0 1) ;PTEN阳性组明显高于阴性组 (P <0 0 1)。结论　survivin、PTEN、p5 3和cyclinD1基因在胃癌的发生、发展中起着不同程度的作用 ,它们的检测对胃癌恶性度的判定、预后和进一步治疗提供有效的依据。survivin、p5 3和cyclinD1的过表达可作为判断肿瘤术后差的指标     

Estradiol attenuates the focal cerebral ischemic injury through mTOR/p70S6 kinase signaling pathway

We previously showed that estradiol prevents neuronal cell death through the activation of Akt and its downstream targets Bad and FKHR. This study investigated whether estradiol modulates the survival pathway through other downstream targets of Akt, including mammalian target of rapamycin (mTOR) and p70S6 kinase. It is known that mTOR is a downstream target of Akt and a central regulator of protein synthesis, cell growth, and cell cycle progression. Adult female rats were ovariectomied and treated with estradiol prior to middle cerebral artery occlusion (MCAO). Brains were collected 24h after MCAO and infarct volumes were analyzed. We confirmed that estradiol significantly reduces infarct volume and decreases the number of positive cells for TUNEL staining in the cerebral cortex. Brain injury-induced a decrease in phospho-mTOR and phospho-p70S6 kinase. Estradiol prevented the injury-induced decrease in Akt activation and phosphorylation of mTOR and p70S6 kinases, and the subsequent decrease in S6 phosphorylation. Our findings suggest that estradiol plays a potent protective role against brain injury by preventing the injury-induced decrease of mTOR and p70S6 kinase phosphorylation.     

Prognostic implication of late gadolinium enhancement on cardiac MRI in light chain (AL) amyloidosis on long term follow up

Background

Light chain amyloidosis (AL) is a rare plasma cell dyscrasia associated with poor survival especially in the setting of heart failure. Late gadolinium enhancement (LGE) on cardiac MRI was recently found to correlate with myocardial amyloid deposition but the prognostic role is not established. The aim is to determine the prognostic significance of LGE in AL by comparing long term survival of AL patients with and without LGE.

Methods

Twenty nine consecutive patients (14 females; 62 ± 11 years) with biopsy-proven AL undergoing cardiac MRI with gadolinium as part of AL workup were included. Survival was prospectively followed 29 months (median) following MRI and compared between those with and without LGE by Kaplan-Meier and log-rank analyses.

Results

LGE was positive in 23 subjects (79%) and negative in 6 (21%). Left ventricular ejection fraction was 66 ± 17% in LGE-positive and 69 ± 12% in LGE-negative patients (p = 0.8). Overall 1-year mortality was 36%. On follow-up, 14/23 LGE-positive and none of LGE-negative patients died (log rank p = 0.0061). Presenting New York Heart Association heart failure class was also associated with poor survival (p = 0.0059). Survival between two LGE groups stratified by heart failure class still showed a significant difference by a stratified log-rank test (p = 0.04).

Conclusion

Late gadolinium enhancement is common and is associated with poor long-term survival in light chain amyloidosis, even after adjustment for heart failure class presentation. The prognostic significance of late gadolinium enhancement in this disease may be useful in patient risk-stratification.     

Association of expression of p53, livin,ERCC1, BRCA1 and PARP1 in epithelial ovarian cancer tissue with drug resistance and prognosis

ObjectiveTo evaluate the correlation between expression of p53, Livin, Excision repair cross-complementation group 1 (ERCC1), BRCA1 and Poly (ADP-ribose) polymerase 1 (PARP 1) in epithelial ovarian cancer (EOC) tissues with platinum-based chemotherapy and prognosis in patients who received either comprehensive surgical staging or cytoreductive surgery.MethodsThe protein expressions level of five potential regulators involved in chemo-resistance, including p53, Livin, ERCC1, BRCA1 and PARP1 in EOC tissues from 66 patients were evaluated using immunohistochemistry method. We also measured preoperative CA125 level measured by an electrochemiluminescence immunoassay (ECLIA) in all patients. Cox proportional hazard regression model was established to identify whether these proteins are associated with overall survival.ResultsChemo-resistance and poor overall survival were shown to be significantly related with positive expressions of p53, Livin, ERCC1, BRCA1 and PARP1. The evaluation of risk factors on the chemo-resistance showed that ERCC1 and BRCA1 are strong risk factors (OR: 21.12 and 21.61, all P < 0.01), while the positive expression of ERCC1, BRCA1 and PARP1 was significantly highly associated with the overall survival (HR: 3.9, 3.7 and 2.6, all P < 0.05, respectively). CA125 levels were significantly higher in patients with positive expression of P53, BRCA1, ERCC1 or Livin compared with those with negative expression (471:146, 667:260, 494:261 and 4589:89 U/ml, respectively, all P < 0.05).ConclusionsThe elevated expression levels of ERCC1 and BRCA1 were identified as significant risk factors for chemo-resistance in EOC. Reduced expression levels of ERCC1, BRCA1 and PARP1 were significantly associated with better overall survival. The CA125 levels were significantly higher in patients with EOC specimens that were positive of p53, BRCA1, ERCC1 and Livin.     

CRP gene variation affects early development of Alzheimer's disease-related plaques

Background

Production of reactive oxygen species (ROS) and proinflammatory cytokines by microglial cells in response to viral brain infection contributes to both pathogen clearance and neuronal damage. In the present study, we examined the effect of herpes simplex virus (HSV)-1-induced, NADPH oxidase-derived ROS in activating mitogen-activated protein kinases (MAPKs) as well as driving cytokine and chemokine expression in primary murine microglia.

Methods

Oxidation of 2', 7'-dichlorodihydrofluorescin diacetate (H₂DCFDA) was used to measure production of intracellular ROS in microglial cell cultures following viral infection. Virus-induced cytokine and chemokine mRNA and protein levels were assessed using real-time RT-PCR and ELISA, respectively. Virus-induced phosphorylation of microglial p38 and p44/42 (ERK1/2) MAPKs was visualized using Western Blot, and levels of phospho-p38 were quantified using Fast Activated Cell-based ELISA (FACE assay). Diphenyleneiodonium (DPI) and apocynin (APO), inhibitors of NADPH oxidases, were used to investigate the role of virus-induced ROS in MAPK activation and cytokine, as well as chemokine, production.

Results

Levels of intracellular ROS were found to be highly elevated in primary murine microglial cells following infection with HSV and the majority of this virus-induced ROS was blocked following DPI and APO treatment. Correspondingly, inhibition of NADPH oxidase also decreased virus-induced proinflammatory cytokine and chemokine production. In addition, microglial p38 and p44/42 MAPKs were found to be phosphorylated in response to viral infection and this activation was also blocked by inhibitors of NADPH oxidase. Finally, inhibition of either of these ROS-induced signaling pathways suppressed cytokine (TNF-α and IL-1β) production, while chemokine (CCL2 and CXCL10) induction pathways were sensitive to inhibition of p38, but not ERK1/2 MAPK.

Conclusions

Data presented herein demonstrate that HSV infection induces proinflammatory responses in microglia through NADPH oxidase-dependent ROS and the activation of MAPKs.