Maternal choline supplementation differentially alters the basal forebrain cholinergic system of young‐adult Ts65Dn and disomic mice

Down syndrome (DS), trisomy 21, is a multifaceted condition marked by intellectual disability and early presentation of Alzheimer's disease (AD) neuropathological lesions including degeneration of the basal forebrain cholinergic neuron (BFCN) system. Although DS is diagnosable during gestation, there is no treatment option for expectant mothers or DS individuals. Using the Ts65Dn mouse model of DS that displays age‐related degeneration of the BFCN system, we investigated the effects of maternal choline supplementation on the BFCN system in adult Ts65Dn mice and disomic (2N) littermates at 4.3–7.5 months of age. Ts65Dn dams were maintained on a choline‐supplemented diet (5.1 g/kg choline chloride) or a control, unsupplemented diet with adequate amounts of choline (1 g/kg choline chloride) from conception until weaning of offspring; post weaning, offspring were fed the control diet. Mice were transcardially perfused with paraformaldehyde, and brains were sectioned and immunolabeled for choline acetyltransferase (ChAT) or p75‐neurotrophin receptor (p75^NTR). BFCN number and size, the area of the regions, and the intensity of hippocampal labeling were determined. Ts65Dn‐unsupplemented mice displayed region‐ and immunolabel‐dependent increased BFCN number, larger areas, smaller BFCNs, and overall increased hippocampal ChAT intensity compared with 2N unsupplemented mice. These effects were partially normalized by maternal choline supplementation. Taken together, the results suggest a developmental imbalance in the Ts65Dn BFCN system. Early maternal‐diet choline supplementation attenuates some of the genotype‐dependent alterations in the BFCN system, suggesting this naturally occurring nutrient as a treatment option for pregnant mothers with knowledge that their offspring is trisomy 21. J. Comp. Neurol. 522:1390–1410, 2014. © 2013 Wiley Periodicals, Inc.     

Treatment of epistaxis in hereditary hemorrhagic telangiectasia with tranexamic acid - a double-blind placebo-controlled cross-over phase IIIB study

Introduction

Epistaxis is the most frequent manifestation in hereditary hemorrhagic telangiectasia, in which no optimal treatment exists. It can lead to severe anemia and reduced quality of life. Positive effects of tranexamic acid, an antifibrinolytic drug, have been reported on epistaxis related to this disorder. We sought to evaluate the efficacy of treating nosebleeds in hereditary hemorrhagic telangiectasia with tranexamic acid.

Materials and Methods

In a randomized, double-blind, placebo controlled, cross-over phase IIIB study, 1 gram of tranexamic acid or placebo was given orally 3 times daily for 3 months for a total of 6 months.

Results

22 patients were included in the intention-to-treat analysis. Hemoglobin levels, the primary outcome measure, did not change significantly (p = 0.33). The secondary outcome measure was epistaxis score and patients reported a statistically significant reduction in nosebleeds, equaling a clinically relevant 54% diminution (p = 0.0031), as compared to the placebo period. No severe side effects were observed.

Conclusion

Tranexamic acid reduces epistaxis in patients with hereditary hemorrhagic telangiectasia.(Clinical trial registration numbers: BfArM 141 CHC 9008–001 and ClinicalTrials.gov NCT01031992)     

Evaluation of immunohistochemical expression of p53, p21, p27, cyclin D1, and Ki67 in oral and oropharyngeal squamous cell carcinoma

J Oral Pathol Med (2012) 41 : 40–46 Background: The purpose of this study was to evaluate whether the immunohistochemical expression of p53, p21, p27, cyclin D1, and Ki67 can predict therapy response and survival in patients with oral and oropharyngeal squamous cell carcinoma treated with preoperative chemoradiation. Methods: Biomarker expression was evaluated by immunohistochemistry in formalin‐fixed, paraffin‐embedded pretreatment biopsies of 111 homogenously treated patients. We assessed the association between clinicopathological variables including response to neoadjuvant chemoradiotherapy as well as the survival of the patients and the expression of the biomarkers as both dichotomized (positive vs. negative) and continuous variables. Results: Biomarker overexpression on the basis of pre‐selected cutoff points was seen in 66 of 111 (59%) cases for p53, in 77 (69%) for p21, in 48 (43%) for p27, in 81 (73%) for cyclin D1, and in 54 (49%) cases for Ki67, respectively. None of the examined biomarkers was able to predict response to neoadjuvant chemoradiotherapy or was associated with survival outcome. Post‐treatment pathologic TNM stage (P < 0.001), pathologic response (P < 0.001), and perineural invasion (P < 0.001) were the only factors having a significant effect on recurrence‐free survival. Post‐treatment pathologic N stage (P = 0.005), post‐treatment pathologic TNM stage (P < 0.001), pathologic response (P < 0.001), and perineural invasion (P = 0.001) had a significant impact on overall survival. Conclusions: Our results suggest that the biomarkers p53, p21, p27, cyclin D1, and Ki67 have no impact on treatment response and survival in patients with oral and oropharyngeal cancer treated with preoperative chemoradiation.     

Combined cytoplasmic and membranous EGFR and p53 overexpression is a poor prognostic marker in early stage oral squamous cell carcinoma

J Oral Pathol Med (2012) 41 : 559–567 Objective: Our aim was to evaluate the expression of several molecules that regulate growth, the cell cycle and signalling pathways including EGFR, p53, p16 and p27 in oral squamous cell carcinomas (OSCC). We examined their utility as prognostic markers by relating to clinicopathological characteristics and the clinical outcome. Patients and methods: Using tissue microarray technology, we analysed 67 primary OSCC and examined immunohistochemical expression of EGFR, p53, p16 and p27. Multivariate analysis was conducted to examine their role in survival. Results: Many of the markers were highly expressed in these cancers. Membranous EGFR expression in 95.2%, both membrane and cytoplasm expression in 35%, p53 expression in 61.6%, p27 expression in 89.5% and p16 expression in 27.9% of cases. In the multivariate analysis, independent prognostic influence of a lower overall survival was determined only for advanced tumour stage (P < 0.001), p53 overexpression (P = 0.004), EGFR cytoplasm and membrane co‐expression location (P = 0.002) and p16 reduced expression (P = 0.002). When considering a subgroup of early stage tumours, p53 overexpression (P = 0.028) and combined membranous and cytoplasm EGFR co‐expression (P = 0.039) were indicators of a lower overall survival. For disease‐free survival, in addition to these three factors, the histological grade (P = 0.011) showed independent prognostic values. Conclusion: The independent value of EGFR subcellular location (cytoplasm and membrane) and p53 overexpression in overall survival even in early stages of OSCC suggests that these markers may serve as reliable biological markers to identify high‐risk subgroups and to guide therapy.     

p21Waf1/Cip1与Skp2在涎腺肿瘤中的表达及意义

目的:研究p21 Waf1/Cip1与Skp2在涎腺良、恶性肿瘤中的表达及临床意义。方法:应用免疫组织化学SABC法检测10例正常涎腺组织、20例涎腺良性肿瘤、33例涎腺恶性肿瘤组织中p21 Waf1/Cip1和Skp2蛋白的表达情况,分析它们表达之间的相关性。结果:p21 Waf1/Cip1在涎腺正常组织以及涎腺良、恶性肿瘤的表达率依次降低,各组之间存在显著性差异(x2=11.113,P=0.006)。Skp2在涎腺恶性肿瘤中的阳性表达率(75.76%)明显高于良性肿瘤组织(35.00%),差异有显著性意义(x2=19.128,P=0.001)。p21 Waf1/Cip1与Skp2在涎腺良性肿瘤中的表达呈负相关,但相关性不明显(r=-0.390,P=0.089);它们在涎腺恶性肿瘤中的表达呈显著性负相关(r=-0.467,P=0.006)。结论:p21Waf1/Cip1低表达以及Skp2高表达与涎腺肿瘤的发生、发展密切相关。Skp2可能通过下调p21 Waf1/Cip1蛋白的表达而参与涎腺肿瘤的形成过程。     

Markers of potential malignancy in chronic hyperplastic candidiasis

Aim: To examine the presence of markers associated with malignancy, including p53, p21 cyclin‐dependent kinase inhibitor 1A, murine double minutes‐2, and others, in chronic hyperplastic candidiasis. Methods: Immunohistochemical methods were used to examine the expression of p53, murine double minutes‐2, p21 cyclin‐dependent kinase inhibitor 1A, metallothionein, and proliferating cell nuclear antigen in 42 chronic hyperplastic candidiasis lesions and 11 non‐infected control tissues. Terminal deoxynucleotidyl transferase‐mediated digoxigenin‐dUTP nick‐end labeling was used to examine apoptosis, which was correlated with p53 expression. These markers were measured in lesions of chronic hyperplastic candidiasis that did not show any epithelial dysplasia or histological signs of malignancy. Results: p53 scores were higher in chronic hyperplastic candidiasis than in controls (P = 0.0046). Murine double‐minutes 2 levels were not elevated. p21 cyclin‐dependent kinase inhibitor 1A was increased in parabasal (P < 0.0001) and basal epithelial cells. Chronic hyperplastic candidiasis lesions showed a similar basal/parabasal metallothionein staining pattern to that seen in normal squamous epithelium. Proliferating cell nuclear antigen was increased (P = 0.0007), as was apoptosis (P = 0.0033). Conclusion: Increased p53 in oral chronic hyperplastic candidiasis suggests an increased potential for malignant change in the epithelium, above that of normal tissues. Further functional investigation is required, as well as clinical follow‐up studies.     

A new genetic abnormality leading to TP53 gene deletion in chronic lymphocytic leukaemia

The analysis of chromosomal abnormalities provides significant prognostic information in patients with chronic lymphocytic leukaemia (CLL), a disease with a highly heterogeneous clinical course. Chromosomal abnormalities commonly found are trisomy 12, del(13)(q14), del(11)(q22-23), del(17)(p13) and del(6)(q21). Translocations are present in some patients and affect regions recurrently involved in CLL. This report describes the clinical and pathological characteristics of four CLL patients showing a new recurrent chromosomal abnormality dic(8;17)(p11;p11), that implied loss of the TP53 gene in all cases. In addition, TP53 gene was mutated in three out of four patients. Mechanically, Low Copy Repeats (LCR) in 17p12 and 8p11 may explain the origin of the translocation by non-allelic homologous recombination (NAHR). Isolated dic(8;17)(p11;p11) in patients with mutated IGHV genes status may not have the same prognostic impact as other mutations or deletions affecting the TP53 gene. Larger series are needed to better evaluate the clinical impact of this chromosomal aberration during the course of the disease.     

mTOR inhibition with rapamycin causes impaired insulin signalling and glucose uptake in human subcutaneous and omental adipocytes

Rapamycin is an immunosuppressive agent used after organ transplantation, but its molecular effects on glucose metabolism needs further evaluation. We explored rapamycin effects on glucose uptake and insulin signalling proteins in adipocytes obtained via subcutaneous (n=62) and omental (n=10) fat biopsies in human donors. At therapeutic concentration (0.01 μM) rapamycin reduced basal and insulin-stimulated glucose uptake by 20-30%, after short-term (15 min) or long-term (20 h) culture of subcutaneous (n=23 and n=10) and omental adipocytes (n=6 and n=7). Rapamycin reduced PKB Ser473 and AS160 Thr642 phosphorylation, and IRS2 protein levels in subcutaneous adipocytes. Additionally, it reduced mTOR-raptor, mTOR-rictor and mTOR-Sin1 interactions, suggesting decreased mTORC1 and mTORC2 formation. Rapamycin also reduced IR Tyr1146 and IRS1 Ser307/Ser616/Ser636 phosphorylation, whereas no effects were observed on the insulin stimulated IRS1-Tyr and TSC2 Thr1462 phosphorylation. This is the first study to show that rapamycin reduces glucose uptake in human adipocytes through impaired insulin signalling and this may contribute to the development of insulin resistance associated with rapamycin therapy.