Plasma Membrane Protein Profiling in Beta‐Amyloid‐Treated Microglia Cell Line

In the responsiveness of microglia to toxic stimuli, plasma membrane proteins play a key role. In this study we treated with a synthetic beta amyloid peptide murine microglial cells metabolically differently labelled with stable isotope amino acids (SILAC). The plasma membrane was selectively enriched by a multi‐stage aqueous two‐phase partition system. We were able to identify by 1D‐LC‐MS/MS analyses 1577 proteins, most of them are plasma membrane proteins according to the Gene Ontology annotation. An unchanged level of amyloid receptors in this data set suggests that microglia preserve their responsiveness capability to the environment even after 24‐h challenge with amyloid peptides. On the other hand, 14 proteins were observed to change their plasma membrane abundance to a statistically significant extent. Among these, we proposed as reliable biomarkers of the inflammatory microglia phenotype in AD damaged tissues MAP/microtubule affinity‐regulating kinase 3 (MARK3), Interferon‐induced transmembrane protein 3 (IFITM3), Annexins A5 and A7 (ANXA5, ANXA7) and Neuropilin‐1 (NRP1), all proteins known to be involved in the inflammation processes and in microtubule network assembly rate.     

Proteomics for Protein Expression Profiling in Neuroscience

As the technology of proteomics moves from a theoretical approach to a practical reality, neuroscientists will have to determine the most appropriate applications for this technology. Neuroscientists will have to surmount difficulties particular to their research, such as limited sample amounts, heterogeneous cellular compositions in samples, and the fact that many proteins of interest are rare, hydrophobic proteins. This review examines protein isolation and protein fractionation and separation using two-dimensional electrophoresis (2-DE) and mass spectrometry proteomic methods. Methods for quantifying relative protein expression between samples (e.g., 2-DIGE, and ICAT) are also described. The coverage of the proteome, ability to detect membrane proteins, resource requirements, and quantitative reliability of different approaches is also discussed. Although there are many challenges in proteomic neuroscience, this field promises many rewards in the future.     

Pituitary Dysfunction in Patients with Intracranial Germ Cell Tumors Treated with Radiotherapy

Objective:To evaluate the endocrine abnormalities in intracranial germ cell tumors (iGCTs) treated with radio-therapy (RT), and to discuss the effects of RT on pituitary functions.Methods: Seventy-seven patients diagnosed with iGCTs who had received RT and endocrine follow-up in Huashan Hospital between January 2010 and July 2017 were retrospectively analyzed, consisting of 49 germinomas and 28 NGGCTs. The median follow-up period was 50.0 months. Fifty-one patients had radiologically proved suprasellar/sellar lesions.Results: The male to female ratio was 62/15. The median endocrine follow-up period was 19 (4, 42) months. The median age at the last endocrine visit was 18 (16, 20) years old. The 5-year overall and recurrence-free survival were both 98.7%. The overall prevalence of central adrenal insufficiency (CAI), central hypothyroidism (CHT), central hypogonadism (CHG), hyperprolactinemia, and central diabetes insipidus (CDI) was 57.3%, 56%, 56.6%, 35.3%, and 52.1%, respectively, after RT. Patients having suprasellar/sellar lesions showed significantly higher post-therapeutic prevalence of hypopituitarism than those who didn’t. Compared to that before RT, CAI, CHT, and CHG weren’t significantly improved while the levels of prolactin and the prevalence of CDI declined significantly (P =.03 and.001). The radiation doses to pituitary and hypothalamus between those with and without CAI, CHT, and CHG weren’t significantly different.Conclusion: The prevalence of hypopituitarism was high in iGCTs, especially in those with suprasellar/sellar involvement. The levels of prolactin and the prevalence of CDI declined significantly after RT. The hypopituitarism in iGCTs was mainly induced by tumor effects, and RT showed no additional damage to pituitary functions in our study.Abbreviations: AFP = alpha-fetoprotein; CAI = central adrenal insufficiency; CDI = central diabetes insipidus; CHG = central hypogonadism; CHT = central hypothyroidism; CT = computed tomography; DA = dopamine; GH = growth hormone; βHCG = beta-human chorionic gonadotropin; HPA = hypothalamus-pituitary-adrenal; HPG = hypothalamus-pituitary-gonadal; HPL = hyperprolactinemia; HPT = hypothalamus-pituitary-thyroid; iGCT = intracranial germ cell tumor; IGF-1 = insulin-like growth factor 1; NGGCT = nongerminomatous germ cell tumors; OS = overall survival; PFS = progression-free survival; PRL = hypothalamus-pituitary-prolactin; RT = radiotherapy     

p63 IHC染色2+截断值可作为骨巨细胞瘤的诊断标记

为评估骨巨细胞瘤(giant cell tumor of bone, GCTOB)中p63表达在鉴别骨巨细胞瘤(GCTOB)中的作用,本研究采用横断面研究,检测50个巨细胞丰富的骨病变中p63的免疫组织化学表达,并评价p63在各肿瘤中的染色强度和程度。免疫组织化学分析显示,94.12%的骨巨细胞瘤(GCTOB)、14.29%的骨肉瘤(osteosarcoma, OSA)、60.00%的非骨化性纤维瘤(non-ossifyingfibroma, NOF)、25.00%的动脉瘤样骨囊肿(aneurysmal bone cyst, ABC)、71.43%的软骨母细胞瘤(chondroblastoma, CB)、66.67%的棕色瘤(Brown tumor)为阳性,而腱鞘巨细胞瘤(giant cell tumor of the tendon sheath, GCTTS)中未检测出p63阳性。对于p63的染色强度,可以观察到58.82%的骨巨细胞瘤(GCTOB)、28.57%的软骨母细胞瘤(CB)和20.00%的非骨化性纤维瘤(NOF)呈现强染色。对于p63的染色程度:观察到58.82%的骨巨细胞瘤(GCTOB)、28.57%的软骨母细胞瘤(CB)和14.29%的骨肉瘤(OSA)尾弥漫性染色,而中等染色在骨巨细胞瘤(GCTOB)中为17.65%,非骨化性纤维瘤(NOF)为20.00%,棕色瘤(Brown tumor)为33.33%。大量骨巨细胞瘤(94.12%)为p63阳性,这比任何其他巨细胞丰富的病变多得多。然而,p63的阳性染色并不是骨巨细胞瘤(GCTOB)特异性的。本研究结论初步表明,p63是鉴别骨巨细胞瘤(GCTOB)与其他骨巨细胞瘤的一种敏感的(97.6%)和相对特异的标志物。考虑到反应的强度和程度,本研究建议采用综合评分方法对p63 IHC染色判读富含巨细胞的病灶,并将2+截断值作为骨巨细胞瘤(GCTOB)的诊断标记。     

Phosphoproteomics Profiling of Nonsmall Cell Lung Cancer Cells Treated with a Novel Phosphatase Activator

Activation of protein phosphatase 2A (PP2A) is a promising anticancer therapeutic strategy, as this tumor suppressor has the ability to coordinately downregulate multiple pathways involved in the regulation of cellular growth and proliferation. In order to understand the systems‐level perturbations mediated by PP2A activation, we carried out mass spectrometry‐based phosphoproteomic analysis of two KRAS mutated non‐small cell lung cancer (NSCLC) cell lines (A549 and H358) treated with a novel small molecule activator of PP2A (SMAP). Overall, this permitted quantification of differential signaling across over 1600 phosphoproteins and 3000 phosphosites. Kinase activity assessment and pathway enrichment implicate collective downregulation of RAS and cell cycle kinases in the case of both cell lines upon PP2A activation. However, the effects on RAS‐related signaling are attenuated for A549 compared to H358, while the effects on cell cycle‐related kinases are noticeably more prominent in A549. Network‐based analyses and validation experiments confirm these detailed differences in signaling. These studies reveal the power of phosphoproteomics studies, coupled to computational systems biology, to elucidate global patterns of phosphatase activation and understand the variations in response to PP2A activation across genetically similar NSCLC cell lines.     

Expression Profiling of Rectal Tumors Defines Response to Neoadjuvant Treatment Related Genes

To date, no effective method exists that predicts the response to preoperative chemoradiation (CRT) in locally advanced rectal cancer (LARC). Nevertheless, identification of patients who have a higher likelihood of responding to preoperative CRT could be crucial in decreasing treatment morbidity and avoiding expensive and time-consuming treatments. The aim of this study was to identify signatures or molecular markers related to response to pre-operative CRT in LARC. We analyzed the gene expression profiles of 26 pre-treatment biopsies of LARC (10 responders and 16 non-responders) without metastasis using Human WG CodeLink microarray platform. Two hundred and fifty seven genes were differentially over-expressed in the responder patient subgroup. Ingenuity Pathway Analysis revealed a significant ratio of differentially expressed genes related to cancer, cellular growth and proliferation pathways, and c-Myc network. We demonstrated that high Gng4, c-Myc, Pola1, and Rrm1 mRNA expression levels was a significant prognostic factor for response to treatment in LARC patients (p<0.05). Using this gene set, we were able to establish a new model for predicting the response to CRT in rectal cancer with a sensitivity of 60% and 100% specificity. Our results reflect the value of gene expression profiling to gain insight about the molecular pathways involved in the response to treatment of LARC patients. These findings could be clinically relevant and support the use of mRNA levels when aiming to identify patients who respond to CRT therapy.     

骨肿瘤端粒长度变化与相关蛋白表达的关系

目的:研究骨肿瘤端粒长度变化与端粒结合蛋白即端粒重复结合因子1(TRF1)和端粒保护因子(POT1),端粒酶催化亚单位(hTERT),肿瘤相关基因P53、c-myc表达的关系,以了解骨肿瘤的分子特征。方法:采用免疫组织化学、端粒定量荧光原位杂交(Telo-FISH)和原位杂交检测了20例骨肉瘤、25例软骨肉瘤、14例骨的纤维结构不良中端粒长度、TRF1、POT1、hTERT、P53、c-myc的表达情况,并进行统计分析。结果:20例骨肉瘤平均长度为0.31,25例软骨肉瘤为0.41,14例骨的纤维结构不良为0.52。统计显示三者间端粒长度有显著差异(P<0.05)。骨肉瘤和软骨肉瘤TRF1、POT1阳性率均显著低于骨纤维结构不良(P<0.05)。而骨肉瘤和软骨肉瘤hTERT基因表达显著高于骨纤维结构不良(P<0.05)。骨肉瘤、软骨肉瘤P53、c-myc阳性率高于骨纤维结构不良(P<0.05)。统计分析骨肿瘤端粒长度变化与端粒结合蛋白TRF1、POT1的表达呈负相关性,与端粒酶hTERT基因表达、与P53蛋白核聚积,以及c-myc癌基因表达呈正相关性。结论:骨肿瘤端粒长度与恶性表型有关、端粒短缩与肿瘤基因突变相关。     

Diverse Bone Morphogenetic Protein Expression Profiles and Smad Pathway Activation in Different Phenotypes of Experimental Canine Mammary Tumors

Background

BMPs are currently receiving attention for their role in tumorigenesis and tumor progression. Currently, most BMP expression studies are performed on carcinomas, and not much is known about the situation in sarcomas.

Methodology/Principal Findings

We have investigated the BMP expression profiles and Smad activation in clones from different spontaneous canine mammary tumors. Spindle cell tumor and osteosarcoma clones expressed high levels of BMPs, in particular BMP-2, -4 and -6. Clones from a scirrhous carcinoma expressed much lower BMP levels. The various clones formed different tumor types in nude mice but only clones that expressed high levels of BMP-6 gave bone formation. Phosphorylated Smad-1/5, located in the nucleus, was detected in tumors derived from clones expressing high levels of BMPs, indicating an active BMP signaling pathway and BMP-2 stimulation of mammary tumor cell clones in vitro resulted in activation of the Smad-1/5 pathway. In contrast BMP-2 stimulation did not induce phosphorylation of the non-Smad pathway p38 MAPK. Interestingly, an increased level of the BMP-antagonist chordin-like 1 was detected after BMP stimulation of non-bone forming clones.

Conclusions/Significance

We conclude that the specific BMP expression repertoire differs substantially between different types of mammary tumors and that BMP-6 expression most probably has a biological role in bone formation of canine mammary tumors.     

Gene Expression Profiling Reveals a Novel Regulatory Role for Sox21 Protein in Mouse Trophoblast Stem Cell Differentiation

Appropriate self-renewal and differentiation of trophoblast stem cells (TSCs) are key factors for proper placental development and function and, in turn, for appropriate in utero fetal growth. To identify novel TSC-specific genes, we performed genome-wide expression profiling of TSCs, embryonic stem cells, epiblast stem cells, and mouse embryo fibroblasts, derived from mice of the same genetic background. Our analysis revealed a high expression of Sox21 in TSCs compared with other cell types. Sox21 levels were high in undifferentiated TSCs and were dramatically reduced upon differentiation. In addition, modulation of Sox21 expression in TSCs affected lineage-specific differentiation, based on both marker analysis and functional assessment. Our results implicate Sox21 specifically in the promotion of spongiotrophoblast and giant cell differentiation and establish a new mechanism through which trophoblast sublineages are specified.     

Expression Profiling of Primary and Metastatic Ovarian Tumors Reveals Differences Indicative of Aggressive Disease

The behavior and genetics of serous epithelial ovarian cancer (EOC) metastasis, the form of the disease lethal to patients, is poorly understood. The unique properties of metastases are critical to understand to improve treatments of the disease that remains in patients after debulking surgery. We sought to identify the genetic and phenotypic landscape of metastatic progression of EOC to understand how metastases compare to primary tumors. DNA copy number and mRNA expression differences between matched primary human tumors and omental metastases, collected at the same time during debulking surgery before chemotherapy, were measured using microarrays. qPCR and immunohistochemistry validated findings. Pathway analysis of mRNA expression revealed metastatic cancer cells are more proliferative and less apoptotic than primary tumors, perhaps explaining the aggressive nature of these lesions. Most cases had copy number aberrations (CNAs) that differed between primary and metastatic tumors, but we did not detect CNAs that are recurrent across cases. A six gene expression signature distinguishes primary from metastatic tumors and predicts overall survival in independent datasets. The genetic differences between primary and metastatic tumors, yet common expression changes, suggest that the major clone in metastases is not the same as in primary tumors, but the cancer cells adapt to the omentum similarly. Together, these data highlight how ovarian tumors develop into a distinct, more aggressive metastatic state that should be considered for therapy development.     

Development and Validation of a Gene-Based Model for Outcome Prediction in Germ Cell Tumors Using a Combined Genomic and Expression Profiling Approach

Germ Cell Tumors (GCT) have a high cure rate, but we currently lack the ability to accurately identify the small subset of patients who will die from their disease. We used a combined genomic and expression profiling approach to identify genomic regions and underlying genes that are predictive of outcome in GCT patients. We performed array-based comparative genomic hybridization (CGH) on 53 non-seminomatous GCTs (NSGCTs) treated with cisplatin based chemotherapy and defined altered genomic regions using Circular Binary Segmentation. We identified 14 regions associated with two year disease-free survival (2yDFS) and 16 regions associated with five year disease-specific survival (5yDSS). From corresponding expression data, we identified 101 probe sets that showed significant changes in expression. We built several models based on these differentially expressed genes, then tested them in an independent validation set of 54 NSGCTs. These predictive models correctly classified outcome in 64–79.6% of patients in the validation set, depending on the endpoint utilized. Survival analysis demonstrated a significant separation of patients with good versus poor predicted outcome when using a combined gene set model. Multivariate analysis using clinical risk classification with the combined gene model indicated that they were independent prognostic markers. This novel set of predictive genes from altered genomic regions is almost entirely independent of our previously identified set of predictive genes for patients with NSGCTs. These genes may aid in the identification of the small subset of patients who are at high risk of poor outcome.