A monolithic microsphere-fiber probe for spatially resolved Raman spectroscopy: Application to head and neck squamous cell carcinomas

The ability to identify precise cancer margins in vivo during a surgical excision is critical to the well-being of the patient. Decreased operative time has been linked to shorter patient recovery time, and there are risks associated with removing either too much or too little tissue from the surgical site. The more rapidly and accurately a surgeon can identify and excise diseased tissue, the better the prognosis for the patient. To this end, we investigate both malignant and healthy oral cavity tissue using the Raman spectroscopy, with a monolithic microsphere-fiber probe. Our results indicate that this probe has decreased the size of the analyzed area by more than an order of magnitude, as compared to a conventional fiber reflection probe. Scanning the probe across the tissues reveals variations in the Raman spectra that enable us to differentiate between malignant and healthy tissues. Consequently, we anticipate that the high spatial resolution afforded by the probe will permit us to identify tumor margins in detail, thereby optimizing tissue removal and improving patient outcomes.

Abstract P2-05-06: Analytical and clinical validation of a fully automated tissue-based quantitative assay (MetaSite Breast™) to detect the likelihood of distant metastasis in hormone receptor (HR)-positive, HER2-negative early stage breast cancer (ESBC)

Background: MetaSite Breast™ is a validated assay to predict risk of distant breast cancer metastasis in patients with HR+/HER2- ESBC. The assay measures the number of MetaSites defined as tumor microanatomic structures composed of MENA protein expressing tumor cells in contact with CD31+ endothelial cells and CD68+ macrophages. Previous studies have demonstrated that an increased number of these microanatomic structures is associated with distant metastasis (DM) in HR+/HER2- ESBC independent of clinicopathologic features. Analytical validation of MetaSite Breast™ demonstrated precision of 97-99% (repeat image analysis of the same slide) and performance of 91-96% (staining and image analysis of serial tumor sections). We sought to further understand the importance of the MetaSite in predicting distant breast cancer metastasis utilizing a fully automated prognostic assay in an independent large patient cohort.

Methods: We conducted a nested case-control study within a cohort of 3,760 patients diagnosed between 1980 and 2000 with invasive breast cancer from the Kaiser Permanente Northwest health care system. Cases (n=259) were women who developed a subsequent distant metastasis; controls, selected using incidence density sampling, were matched closely to cases (1:1) on age at and calendar year of primary diagnosis. Of the 481 patient tumor samples evaluated in this study, 57% were HR+/HER2-, 19% were triple negative (TN), and 15% were HER2+ disease. Multivariate models were adjusted for clinical factors including: lymph node status, tumor size, tumor grade, and HRT; as well as matching variables: age and year of diagnosis. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression.

Results: In the HR+/HER2- group, MetaSite Score (MS) ranged from 0-357 and the mean was 44.6. MS was a significant predictor of DM (P=0.039) in patients with HR+/HER2- disease. Cut-points based on tertiles of MS in all 259 controls defined intermediate (13-41) and high (>41) risk groups that were significantly associated with risk of DM versus the low risk group (OR=2.24; 95%CI=1.23-4.13, P=0.009) and (OR=2.94; 95%CI=1.62-5.41, P=0.0005), respectively. Univariate estimates of absolute risk of DM with cutoffs based on 90% sensitivity and specificity were 9.4% for the low risk group (MS<7), 14.1% for the intermediate (MS=7-91), and 23.4% for the high (MS>91). When adjusted for clinical factors, estimates of absolute risk of DM were 6.6%, 14.1%, and 33.0% for the low, intermediate, and high risk groups, respectively. A binary cut-point for the high risk group was determined (MS>14) and was significant with a 2-fold higher risk of DM versus the low risk group and adjusted for clinical covariates (P=0.036). MS was not positively associated with DM in TN or HER2+ disease.

Conclusions: MetaSite Breast™ significantly predicted the risk of distant breast cancer metastasis in ESBC patients with HR+/HER2-disease, independent of classical clinicopathologic features.

Citation Format: Donovan MJ, Jones JG, Entenberg DR, Condeelis JS, D'alfonso TM, Gustavson M, Molinaro A, Oktay MH, Xue X, Sparano JA, Peterson MA, Podznyakova O, Rohan TE, Shuber AP, Gertler FB, Ly A, Divelbiss ME, Hamilton DA. Analytical and clinical validation of a fully automated tissue-based quantitative assay (MetaSite Breast™) to detect the likelihood of distant metastasis in hormone receptor (HR)-positive, HER2-negative early stage breast cancer (ESBC) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-05-06.

Indoleamine 2,3-dioxygenase (IDO) induced by Leishmania infection of human dendritic cells

Dendritic cells (DC) play a pivotal role in regulating immunity, establishing immunologically privileged tissue microenvironments and maintaining homoeostasis. It is becoming increasingly clear that one key mechanism that mediates many DC functions is production of the immunomodulatory enzyme indoleamine 2,3-dioxygenase (IDO). For pathogens that cause chronic infection, exploitation of host DCs is a solution to establish and persist within a host. Leishmania parasites cause a range of clinical manifestations, all involving chronic infection, and are proficient at avoiding immune responses. We demonstrate here that infection of human myeloid-derived DC with L. major and L. donovani induces IDO expression using a mechanism that involves autocrine or paracrine stimulation with a DC-secreted factor. Leishmania-induced IDO suppresses allogeneic and tetanus toxoid-specific lymphocyte proliferation, an inhibition that is reversed with the IDO inhibitor, 1-methyl tryptophan (1-MT). Furthermore, IDO expression by human DC does not require live Leishmania infection, as parasite lysates also up-regulate IDO mRNA production. Our data suggest that one mechanism Leishmania parasites utilize to circumvent immune clearance may be to promote the induction of IDO among host DC within the infection microenvironment.

Novel image analysis tools for evaluating the androgen receptor in the prostate needle biopsy: Impact on future systems-based outcome models

56

Background: A systems-based model was previously developed and validated to predict disease progression (DP) using pretreatment clinical data and standardized, robust prostate needle biopsy (PNB) tissue metrics. We sought to apply novel, advanced immunofluorescent (IF) image analysis methods to re-assess PNB androgen receptor (AR) and Ki67 expression profiles and identify cut-points useful for understanding and guiding therapeutic decision making.

Methods: Pretreatment clinical features and PNB H&E / IF images on 306 patients (91% cT1-T2b, 66% PSA</=10ng/mL; 49% Gleason biopsy score </=6) from the original study cohort were obtained. IF images were re-processed using a novel CK18 and DAPI algorithm to optimize segmentation of the tumor (epithelial) nuclear (TEN) and stromal compartments. The original threshold for determining TEN Ki67was retained. An enhanced image analysis approach was applied to calculate the normalized ratio of maximum AR levels in TEN to stromal nuclei. Feature performance was evaluated with the concordance index (CI); AR and Ki67 cut-point (CP) analysis and new multivariate models were completed.

Results: Increasing amounts of Ki67 and two new AR features reflecting different percentages of the maximum AR level in TEN were associated with a shorter time to DP (Ki67 CI0.37, AR-ratio 21, CI0.30 and AR-ratio 22, CI0.33). Several cut-points were identified including: Ki67 CP 0.04, hazard ratio (HR) of 3.1, p-value 0.0005 (sensitivity 64%, specificity 68%); ARratio-21 CP 0.90, HR 3.8, p-value 0.0001 (sensitivity 78%, specificity 73%) and ARratio-22 CP 0.87, HR 2.2, p-value 0.013 (sensitivity 68%, specificity 68%). A multivariate model for predicting DP consisted of 4 weighted features including the biopsy Gleason score, the ARratio-22, and two morphometric (H&E&IF) variables.

Conclusions: Novel image analysis methods to analyze biomarker attributes in PNB specimens confirm and enhance our understanding of AR and Ki67 in disease progression. Such approaches will become useful tools for finalizing biomarker cut-points, performing pharmacodynamic assessment and establishing parameters for guiding therapy.

[Table: see text]

Personalized approach to prostate cancer prognosis

Personalized medicine in the management of patients with prostate cancer is limited to the integration of patient attributes such as age, genetic risk and comorbidities with specific clinical-pathologic variables including serum prostate specific antigen (PSA), imaging and features from the diagnostic prostate needle biopsy or prostatectomy specimen including tumor differentiation (i.e. Gleason), volume and extent of disease (i.e. tumor length and / or percentage, number of positive cores at diagnosis or pathologic stage post surgery including margin status). Although the development of various clinical statistical instruments such as nomograms have provided a mechanism to interrogate such variables, most urologists rely on basic prognostic features of stage, grade and PSA along with clinical judgment to define and understand individual risk and predict health outcomes. Furthermore, unlike other tumor types such as breast cancer, there are no routine ancillary diagnostic studies performed on the prostate needle biopsy or prostatectomy specimen to support and refine the treatment decision process for the individual patient. In this review we will provide a summary of the current practice of predictive statistical modeling in prostate cancer and explore how technical advances in functional histology have played a role in the development and incorporation of a systems based platform for providing a patient-specific risk profile useful for clinical decision making.

Characterization of lymphoid infiltrates in prostatectomy specimens post neoadjuvant hormonal therapy using quantitative immunofluorescence and RNA FISH

e16104

Background: Immunotherapy for advanced prostate cancer requires an understanding of the host response including lymphocyte subsets and cytokine expression. Using quantitative immunofluorescence (IF), image analysis and RNA FISH we examined a series of prostatectomy specimens from patients, ± neoadvjuvant hormonal therapy (NHT) and determined their baseline immune characteristics. Methods: CD4,8,25,45,68,69,86 and Foxp3 were evaluated by IF and IFNg with RNA FISH on prostatectomy specimens from 40 patients with T1c-T3 prostate cancer; 20 control and 20 post long-term NHT. Sections were analyzed with three multiplex IF assays, triplicate images acquired with spectral imaging, digitally masked and processed with IF image analysis software. IFNg RNA transcript localization was performed on all 40 patients using published protocols. Results: There was a predominance of CD8 in both control and NHT patients with a high but variable level of CD86 and 69 across the entire cohort, reflecting T cell activation. CD68 appeared reduced in NHT, but this change was not statistically significant. Number of Treg (CD4+/CD25+/Foxp3+) cells were similar between groups; however, in NHT an increased Treg population was associated with an elevated preoperative PSA compared with controls (p<0.05). IFNg transcript activity was low in the entire cohort and limited to tumor epithelial cells. Conclusions: The prominent CD8 expression and low level of IFNg in both control and NHT groups suggest an ongoing but not overly active immune response. Multiplex IF and in situ RNA FISH are useful tools for developing a disease phenotype and provide the necessary parameters for evaluating gene-protein expression especially in pharmacodynamic studies.

[Table: see text]

Inhibition of groups 1 and 2 CD1 molecules on human dendritic cells by Leishmania species

Dendritic cells are potent immune-activating cells, which traditionally are thought of as presenters of protein antigen to lymphocytes to initiate an immune response. Recently, another mechanism of immune surveillance, the detection of lipid antigens, has been found to be mediated by the nonpolymorphic family of CD1 molecules. There are two different CD1 families, Group 1 consisting of CD1a, CD1b and CD1c, and Group 2 consisting only of CD1d. Leishmania donovani-infected dendritic cells have previously been demonstrated to exhibit decreased surface levels of Group 1 CD1 molecules and are no longer able to initiate a CD1b-restricted T cell response. In contrast to L. donovani, which disseminates to the visceral organs, L. major remains localized, forming a cutaneous lesion. We investigate here whether L. major, the aetiological agent of cutaneous leishmaniasis, also inhibits CD1 expression. We demonstrate that infection of human monocyte-derived dendritic cells with either L. major or L. donovani results in transcriptional down-regulation of both Groups 1 and 2 CD1 molecules. Furthermore, infection of monocytes during differentiation results in a cell phenotype similar to undifferentiated monocytes. Finally, we demonstrate that this down-regulation is not mediated by lipophosphoglycan or other phosphoglycans.

A systems pathology model for predicting overall survival in patients with refractory, advanced non-small cell lung cancer (NSCLC) treated with gefitinib

18065

Background: The abundant expression of the epidermal growth factor receptor (EGFR) in a variety of solid tumors including non-small cell lung cancer (NSCLC), head and neck, breast, colon and brain has made it an attractive target for various selective molecular therapeutics, including the tyrosine kinase inhibitor gefitinib. The recent evidence of activating mutations in EGFR combined with clinical - demographic features has suggested that subgroups of patients with NSCLC are most likely to respond to selective therapies. We sought to determine whether the integration of clinical variables, tumor morphometry and quantitative protein profiles using support vector machines could identify a set of features which predicts overall survival in patients with NSCLC treated with gefitinib. Methods: We analyzed tumor samples from 109 patients with advanced refractory NSCLC treated with gefitinib. Formalin fixed, paraffin embedded tissue samples were evaluated with the following assays: Hematoxylin and Eosin image morphometry, EGFR DNA mutation analysis, EGFR protein immunohistochemistry and quantitative immunofluorescence with the following antibodies: CK18, Ki67, Caspase 3 activated, cd34, EGFR, phosphorylated-EGFR, phosphorylated-ERK, phosphorylated-AKT, PTEN, Cyclin D1, phosphorylated-m-TOR, PI3-K, VEGF, KDR (VEGFR2) and phosphorylated KDR. A predictive model was developed using support vector regression for censored data. Results: 4 of 87 patients had tyrosine kinase domain mutations in exons 19, 20 or 21. Utilizing 51 patients with complete data profiles (i.e. clinical, image morphometry and immunofluorescence), a model predicting overall survival was developed with a concordance index of 0.74. Poor performance status, poorly differentiated histology by morphometry and increased levels of activated caspase 3, phosphorylated KDR (VEGFR2) and cyclin D1 were associated with reduced survival. Conclusion: The integration of clinical, imaging and biomarker data identified a set of features which were associated with a more aggressive disease phenotype and resulted in overall poor survival.

[Table: see text]

Androgen receptor (AR) level in the prostatectomy specimen predicts time to disease progression post androgen suppression therapy

5065

Background: The androgen receptor (AR) plays an important role in the initiation and growth of prostate cancer and its subsequent response to hormone therapy. Previous analyses, including our own, have determined that elevated AR protein in the prostatectomy specimen is associated with progression of disease. We hypothesized that AR levels may also be predictive of response to androgen deprivation therapy (ADT) by evaluating time to castrate rise in PSA in patients treated with ADT at the time of a biochemical recurrence. By utilizing quantitative immunofluorescence (IF) and spectral imaging we evaluated AR content as an independent predictor of therapeutic outcome. Methods: 63 of 881 patients treated by radical prostatectomy had received ADT for a biochemical rise in PSA and or clinical progression of their disease. 32 of 63 patients had progressed post-ADT with a castrate rise in PSA. Tissue microarrays with triplicate patient cores were stained with a multiplex immunofluorescent assay (IF) which contained the nuclear marker DAPI, along with the following antibodies: Androgen Receptor (AR), Racemase (AMACR), CK18, HMWK and p63. IF images were acquired with spectral un-mixing employed to develop antibody-cell-specific gray scale images. Utilizing image analysis algorithms, quantitative features including intensity and area for selected antigens was generated. Results: Eleven IF antigen features were evaluated after feature selection and filtering using the concordance index with respect to outcome. A total of 5 features were statistically significant for predicting time to progression post therapy of which 2 features (AR intensity within AMACR (+) and (-) epithelial cells; p=0.0003 and p=0.0021, respectively) demonstrated that elevated levels of AR were associated with a shortened time to castrate rise in PSA post ADT. Clinical features alone were not found to be statistically significant with respect to predicting outcome. Conclusions: AR levels in the prostatectomy sample appears to be a useful indicator for determining therapeutic ADT response and potentially guiding future treatment decision and patient monitoring.

No significant financial relationships to disclose.

Systems pathology for building predictive models: The androgen receptor as a prototype biomarker in prostate cancer progression and targeted therapeutic response assessment

4504

Background: A functional androgen receptor (AR) signaling axis plays a critical role in prostate cancer (PCA) development and progression across the clinical spectrum of the illness. Following diagnosis, most prostate cancers respond to treatments that block circulating androgen levels or block AR action. The measurement of AR levels in tumor tissue samples has the potential to provide prognostic information, to treatment selection, and a measure of the pharmacodynamic effect of a therapeutic agent(s) designed to reduce AR levels or block AR action. Existing methods to assess AR antigen levels in tissue are subjective, we have developed a systems pathology strategy for interrogating biomarker assessment in a predictive model by integrating clinical data with histological and quantitative antigen profiles. Methods: Tissue microarrays from 366 MSKCC patients were stained with H&E, images captured, analyzed and quantitative cellular features produced. Immunohistochemistry (IHC) was performed for AR and a staining index generated. A multiplex immunofluorescent (IF) assay using DAPI, CK18 and AR was performed on a subset of patients. IF mages were acquired and specific IF scripts were used to generate quantitative features of AR which were compared with AR IHC data. Results: Androgen Receptor levels by IHC in PCA demonstrated that a high-level of expression was associated with a greater risk of PSA-relapse within 5 years. (P < 0.0001; cut point 100). The correlation of AR IF with AR IHC established that all derived AR-IF measurements were statistically associated with the AR-IHC data. Furthermore, in a very preliminary model using machine learning and feature selection to predict PSA recurrence, 1AR-IF feature (epithelial and stromal AR) along with 2 clinical variables was selected with a concordance index of 0.80. Conclusion: AR levels in newly diagnosed localized prostate cancer are associated with clinical outcome. The levels can be assessed accurately and in a standardized manner using quantitative multiplex antigen methods. Such approaches are critical for evaluating biomarkers, especially when determining therapeutic response and clinical endpoints.

[Table: see text]

Structure of the histone-core octamer in KCl/phosphate crystals at 2.15 A resolution

The structure of the native chicken histone octamer, crystallized in 2 M KCl, 1.35 M potassium phosphate pH 6.9, has been refined at 2.15 A resolution to a final R factor of 21.4% and an R(free) of 25.2%. Unique crystal-packing interactions between histone-core octamers are strong and one of them (area 4000 A(2)) involves two chloride ions and direct interactions between six acidic amino-acid residues on one octamer and the equivalent number of basic residues on the next. These interactions are on the structured part of the octamer (not involving tails). Five phosphate ions, 23 chloride ions and 437 water molecules have been identified in the structure. The phosphate and some chloride ions bind to basic amino-acid residues that interact with DNA in the nucleosome. The binding of most of the anions and the packing interactions are unique to these crystals. In other respects, and including the positions of four chloride ions, the octamer structure is very close to that of octamers in nucleosome-core particle crystals, particularly with respect to 'docking' sequences of the histone H2As and H4s. These sequences together with the H2B-H4 four-helix bundles stabilize the histone structure in the nucleosome and prevent the dissociation of the (H2A-H2B) dimers from the (H3-H4)(2) tetramer. Possible reasons why this happens at high salt in the absence of DNA are given.

Atherosclerosis: a cancer of the blood vessels?

A series of molecular pathways have in common a significant role in the pathogenesis and progression of atherosclerosis and cancer. Shared mechanisms implicated for both diseases include oxidative stress and the cellular damage that results from it, toxic metabolites produced by cigarette smoking, and increased dietary fat intake. Atherosclerosis may begin when an injury or infection mutates or transforms a single arterial smooth muscle cell in the progenitor of a proliferative clone, similar to the most widely held carcinogenesis theory. Cell proliferation regulatory pathways have been associated with plaque progression, stenosis, and restenosis after angioplasty and with cancer progression. Alterations in cell adhesion molecules have been linked to plaque formation and thrombosis and to tumor invasion and metastasis. Altered expression of proteases associated with thrombolysis has been implicated in atherosclerotic plaque expansion and hemorrhage and in the invasion and metastasis of malignant neoplasms. Ligand-growth factor receptor interactions have been associated with early atherosclerotic lesions and with cancer development and spread. Nuclear transcription factors have been associated with progression of both diseases. Angiogenesis modulators have been linked to plaque expansion and restenosis of atherosclerotic lesions and to local and metastatic tumor expansion.

Atherosclerosis and cancer: common molecular pathways of disease development and progression

Recently, a series of shared molecular pathways have emerged that have in common a significant role in the pathogenesis and progression of both atherosclerosis and cancer. Oxidative stress and the cellular damage that results from it have been implicated in a wide variety of disease processes including atherogenesis and neoplasia. Toxic metabolites produced by cigarette smoking and increased dietary fat intake are implicated in the pathogenesis of both diseases. It has been hypothesized that atherosclerosis may begin when an injury or infection mutates or transforms a single arterial smooth muscle cell in the progenitor of a proliferative clone similar to the most widely held theory of carcinogenesis. Cell proliferation regulatory pathways including genes involved in the GIS checkpoint (p53, pRb, p15, p16, and cyclins A, D, E, and cdk 2,4) have been associated with plaque progression, stenosis and restenosis after angioplasty as well as in cancer progression. Alterations in cell adhesion molecules (integrins, cadherin-catenins) have been linked to plaque formation and thrombosis as well as to tumor invasion and metastasis. Altered expression of proteases associated with thrombolysis has been implicated in atherosclerotic plaque expansion and hemorrhage and in the invasion and metastasis of malignancy. Ligand-growth factor receptor interactions (tyrosine kinases) have been associated with early atherosclerotic lesions as well as cancer development and spread. Nuclear transcription factors such as NFkappaB have been associated with progression of both diseases. Angiogenesis modulators have recently been linked to plaque expansion and restenosis of atherosclerotic lesions as well as local and metastatic tumor expansion. Common disease treatments, such as the use of growth factor inhibitors and radiation treatment, established anticancer treatments, were recently introduced into atherosclerosis therapeutic strategies to prevent restenosis after angioplasty and endarterectomy. In conclusion, a series of molecular pathways of disease development and progression common to atherosclerosis and cancer support that the world's two most common diseases are far more closely aligned than previously believed and that emerging anti-inflammatory and antiproliferative therapeutic strategies may ultimately be efficacious in both conditions.

Brain derived neurotrophic factor is an endothelial cell survival factor required for intramyocardial vessel stabilization

Brain derived neurotrophic factor, BDNF, is a neurotrophin best characterized for its survival and differentiative effects on neurons expressing the trk B receptor tyrosine kinase. Although many of these neurons are lost in the BDNF(−)(/)(−)mouse, the early postnatal lethality of these animals suggests a wider function for this growth factor. Here, we demonstrate that deficient expression of BDNF impairs the survival of endothelial cells in intramyocardial arteries and capillaries in the early postnatal period, although the embryonic vasculature can remodel into arteries, capillaries and veins. BDNF deficiency results in a reduction in endothelial cell-cell contacts and in endothelial cell apoptosis, leading to intraventricular wall hemorrhage, depressed cardiac contractility and early postnatal death. Vascular hemorrhage is restricted to cardiac vessels, reflecting the localized expression of BDNF and trk B by capillaries and arterioles in this vascular bed. Conversely, ectopic BDNF overexpression in midgestational mouse hearts results in an increase in capillary density. Moreover, BDNF activation of endogenous trk B receptors supports the survival of cardiac microvascular endothelial cells cultured from neonatal mice. These results establish an essential role for BDNF in maintaining vessel stability in the heart through direct angiogenic actions on endothelial cells.

Initial differentiation of the metanephric mesenchyme is independent of WT1 and the ureteric bud

The early development of the metanephric kidney is characterized by the induced differentiation of mesenchymal cells into a stem cell population that undergoes a mesenchymal to epithelial transformation in response to stimuli from the ureteric bud. The Wilms' tumor suppressor gene, Wt1, is required for mesenchymal cells to complete this developmental program. In the absence of WT1, a prospective metanephric mesenchyme appears, but becomes apoptotic, and outgrowth of the ureteric bud from the Wolffian duct does not occur. Therefore, the examination of Wt1 -/- embryos allows the determination of those markers of early metanephric differentiation that do not require the ureteric bud or WT1 for their expression. Here, we demonstrate that several markers, including Pax-2, Six-2, and GDNF, were present as RNAs in the metanephric mesenchyme of Wt1 -/- embryos. These findings demonstrate that the metanephric mesenchyme in mutant embryos has begun to differentiate towards the nephrogenic lineage, and that this early differentiation does not require either WT1 or the presence of the ureteric bud. To determine whether WT1 functions other than to induce expression of factors that stimulate ureteric bud outgrowth, Wt1 -/- metanephric mesenchymes were recombined with wild-type ureteric buds in organ culture, but this failed to rescue tubulogenesis. However, the Wolffian duct from Wt1 -/- embryos was a competent inducer of wild-type metanephric mesenchyme.

Increased LDL cholesterol and atherosclerosis in LDL receptor-deficient mice with attenuated expression of scavenger receptor B1

Scavenger receptor BI (SR-BI) is a multiligand cell-surface receptor that plays a central role in high density lipoprotein homeostasis in rodents. To investigate a role for SR-BI in atherosclerosis, mice with attenuated SR-BI expression were crossed with low density lipoprotein (LDL) receptor-deficient mice. Compound-homozygous mutants showed increased plasma cholesterol, surprisingly due primarily to increased LDL cholesterol and apolipoprotein B levels. LDL turnover studies showed that this resulted from increased LDL cholesterol production rather than decreased LDL catabolism. Atherosclerotic lesion size was significantly increased in male compound-mutant mice relative to LDL receptor-deficient controls (93 427+/-16 079 versus 34 448+/-5 331 microm(2), respectively; P=0.003). The proatherogenic effect of attenuated SR-BI expression may in part be due to increased LDL cholesterol levels. These findings suggest that upregulation of the receptor could have therapeutic potential for the treatment of atherosclerosis.

Synthesis of allysine ethylene acetal using phenylalanine dehydrogenase from Thermoactinomyces intermedius

Allysine ethylene acetal [(S)-2-amino-5-(1,3-dioxolan-2-yl)-pentanoic acid (2)] was prepared from the corresponding keto acid by reductive amination using phenylalanine dehydrogenase (PDH) from Thermoactinomyces intermedius ATCC 33205. Glutamate, alanine, and leucine dehydrogenases, and PDH from Sporosarcina species (listed in order of increasing effectiveness) also gave the desired amino acid but were less effective. The reaction requires ammonia and NADH. NAD produced during the reaction was recyled to NADH by the oxidation of formate to CO(2) using formate dehydrogenase (FDH). PDH was produced by growth of T. intermedius ATCC 33205 or by growth of recombinant Escherichia coli or Pichia pastoris expressing the Thermoactinomyces enzyme. Using heat-dried T. intermedius as a source of PDH and heat-dried Candida boidinii SC13822 as a source of FDH,98%, but production of T. intermedius could not be scaled up. Using heat-dried recombinant E. coli as a source of PDH and heat-dried Candida boidinii 98%. In a third generation process, heat-dried methanol-grown P. pastoris expressing endogenous FDH and recombinant Thermoactinomyces98% ee.

Structural characterisation of the native fetuin-binding protein Scilla campanulata agglutinin: a novel two-domain lectin

The three-dimensional structure of a 244-residue, multivalent, fetuin-binding lectin, SCAfet, isolated from bluebell (Scilla campanulata) bulbs, has been solved at 3.3 A resolution by molecular replacement using the coordinates of the 119-residue, mannose-binding lectin, SCAman, also from bluebell bulbs. Unlike most monocot mannose-binding lectins, such as Galanthus nivalis agglutinin from snowdrop bulbs, which fold into a single domain, SCAfet contains two domains with approximately 55% sequence identity, joined by a linker peptide. Both domains are made up of a 12-stranded beta-prism II fold, with three putative carbohydrate-binding sites, one on each subdomain. SCAfet binds to the complex saccharides of various animal glycoproteins but not to simple sugars.

A role for smad6 in development and homeostasis of the cardiovascular system

Smad proteins are intracellular mediators of signalling initiated by Tgf-betasuperfamily ligands (Tgf-betas, activins and bone morphogenetic proteins (Bmps)). Smads 1, 2, 3, 5 and 8 are activated upon phosphorylation by specific type I receptors, and associate with the common partner Smad4 to trigger transcriptional responses. The inhibitory Smads (6 and 7) are transcriptionally induced in cultured cells treated with Tgf-beta superfamily ligands, and downregulate signalling in in vitro assays. Gene disruption in mice has begun to reveal specific developmental and physiological functions of the signal-transducing Smads. Here we explore the role of an inhibitory Smad in vivo by targeted mutation of Madh6 (which encodes the Smad6 protein). Targeted insertion of a LacZ reporter demonstrated that Smad6 expression is largely restricted to the heart and blood vessels, and that Madh6 mutants have multiple cardiovascular abnormalities. Hyperplasia of the cardiac valves and outflow tract septation defects indicate a function for Smad6 in the regulation of endocardial cushion transformation. The role of Smad6 in the homeostasis of the adult cardiovascular system is indicated by the development of aortic ossification and elevated blood pressure in viable mutants. These defects highlight the importance of Smad6 in the tissue-specific modulation of Tgf-beta superfamily signalling pathways in vivo.

Purification of histone core octamers and 2.15 A X-ray analysis of crystals in KCl/phosphate

Intact histone octamers, produced by a new method quickly and in bulk, were crystallized in KCl/phosphate, and the X-ray data were analysed to 2.15 A, confirming a P65 space group. This environment preserves the high-resolution structure of the octamers and will be useful for studying them with other functionally important molecules. The octamers form into left-handed superhelices hexagonally spaced by 158.65 A, having a pitch of 102.57 A with six octamers per turn. A dipotassium tetraiodo mercurate derivative had good phasing power and should prove valuable in refining the structure after molecular-replacement analysis with lower resolution coordinates; the heavy atom was isomorphously placed at a unique site between the two H3-cysteine residues in the octamer.

Distribution of murine mannose receptor expression from early embryogenesis through to adulthood

The mannose receptor is a 175-kDa transmembrane glycoprotein that appears to be expressed on the surface of terminally differentiated macrophages and Langerhans cells. The ectodomain of the mannose receptor has eight carbohydrate recognition domains. The receptor recognizes the patterns of sugars that adorn a wide array of bacteria, parasites, yeast, fungi, and mannosylated ligands. Clearance studies in whole animals have localized radiolabeled ligands, such as mannosylated bovine serum albumen, not only to macrophages, but also to liver sinusoidal endothelial cells. Hitherto, there has been no comprehensive analysis of expression of the mannose receptor in embryonic and adult mouse tissues. In this study, we have undertaken a systematic survey of the expression of the mannose receptor from early embryogenesis through to adulthood. The mannose receptor is expressed on tissue macrophages throughout the adult mouse as expected. However, the mannose receptor is first observed on embryonic day 9 on cells that line blood island vessel walls in the yolk sac. The mannose receptor is localized on sinusoidal endothelial cells in embryonic liver by embryonic day 11 and in bone marrow at embryonic day 17. This pattern persists in these organs throughout embryogenesis into adulthood when sinusoidal endothelial cells of lymph nodes also express the mannose receptor. The receptor is also found on lymphatic endothelial cells of small intestine. In contrast, sinusoids of spleen and thymus do not express mannose receptor antigen. This study demonstrates that the mannose receptor is expressed on tissue macrophages and on subsets of vascular and lymphatic endothelial cells. Thus, the mannose receptor maybe a marker of the so-called reticuloendothelial system.

Cystic neuroblastoma: emphasis on gene expression, morphology, and pathogenesis

Cystic neuroblastoma (CN) is an unusual variant of neuroblastoma characterized by a grossly visible cyst(s) and almost always distinctive microcysts on light microscopy. Rarely, CN will appear solid grossly, but microcystification will be present. We examined the clinical, pathologic, and biologic features of 17 cases of CN. The majority of CN had been detected by prenatal ultrasound. The tumors were favorable stage, stroma-poor, but with low or intermediate mitotic-karyorhectic indices and had favorable biologic markers reflected by aneuploidy and by an absence of N-myc amplification and chromosome 1p deletions. However, the high trk expression typically identified in good risk tumors was absent. Although the complete natural history of CN is not fully defined, our experience suggests that some tumors progress in size, whereas others may spontaneously regress or mature. The clinical outcome is excellent, as is expected in localized and stage 4S neuroblastoma in infancy.

Targeted deletion of all isoforms of the trkC gene suggests the use of alternate receptors by its ligand neurotrophin-3 in neuronal development and implicates trkC in normal cardiogenesis

We have generated null mutant mice that lack expression of all isoforms encoded by the trkC locus. These mice display a behavioral phenotype characterized by a loss of proprioceptive neurons. Neuronal counts of sensory ganglia in the trkC mutant mice reveal less severe losses than those in NT-3 null mutant mice, strongly suggesting that NT-3, in vivo, may signal through receptors other than trkC. Mice lacking either NT-3 or all trkC receptor isoforms die in the early postnatal period. Histological examination of trkC-deficient mice reveals severe cardiac defects such as atrial and ventricular septal defects, and valvular defects including pulmonic stenosis. Formation of these structures during development is dependent on cardiac neural crest function. The similarities in cardiac defects observed in the trkC and NT-3 null mutant mice indicate that the trkC receptor mediates most NT-3 effects on the cardiac neural crest.

Radiologic-Pathologic Conference of Children's Hospital Boston: intraconal mass in the orbit of an infant

A 16-month-old boy presented with left exophthalmos. He was found to have an enhancing intraconal soft-tissue mass. The differential diagnosis of the mass is discussed. The lesion was proven to be a malignant ectomesenchymoma, a very unusual tumor.

Radiologic-Pathologic Conference of Children's Hospital Boston: bilateral asymptomatic renal enlargement

An otherwise healthy 11-month-old boy presented with bilateral abdominal masses. Imaging findings, differential diagnosis, histological findings, and pertinent discussion are presented.

Isolated testicular relapse in an adolescent 5 years following allogeneic bone marrow transplantation for acute myelogenous leukemia

A case of isolated testicular relapse occurring 5 years after allogeneic bone marrow transplantation (BMT) for acute myelogenous leukemia (AML) is reported. The patient presented with M4 AML at age 13 and underwent allogeneic BMT in first remission, 5 months after diagnosis. He had no acute graft-versus-host disease (GVHD) but developed mild chronic GVHD 5 months following transplant and received immunosuppressive therapy for the next 2 years. Five years post-transplant he had an isolated testicular relapse that was treated with chemotherapy and testicular radiation. The patient remains in remission 17 months following relapse and more than 15 months following the cessation of therapy.

Alpha 3 beta 1 integrin has a crucial role in kidney and lung organogenesis

A mutation was targeted to the murine alpha3 integrin gene. Homozygous mutant mice survived to birth, but died during the neonatal period. The mutation caused abnormal kidney and lung development. Mutant kidneys displayed decreased branching of the medullary collecting ducts, although the number of nephrons was not altered. Proximal tubules exhibited two distinct subsets of abnormalities, with the epithelial cells either containing excess lysosomes or becoming microcystic. In addition, glomerular development was markedly affected. In mutant kidneys, the extent of branching of glomerular capillary loops was decreased, with capillary lumina being wider than normal. The glomerular basement membrane was disorganized and glomerular podocytes were unable to form mature foot processes. Branching of the bronchi in lungs of mutant mice was also decreased and the large bronchi extended to the periphery. These results indicate a role for integrin receptors in basement membrane organization and branching morphogenesis.

Neurotrophin and neurotrophin receptors in human fetal kidney

Vertebrate kidney development involves a series of complex interactions between the ureteric bud and undifferentiated mesenchyme resulting in the production of the nephron unit. These interactions are thought to be dependent on a variety of locally derived soluble factors, including peptide growth factors and their receptors. We have extensively analyzed the neurotrophins (NT) and their receptors during human kidney development. The neurotrophin receptors p75 and trk were both present within cells of early glomerular/tubular structures but absent from uninduced mesenchyme. Later in organogenesis, the NTs NT-3 and BDNF colocalized with their respective receptors in differentiated tubules. These findings suggested that the NT:receptor complex was not involved in the early inductive events of renal development but was responsible for postinductive tubulogenesis and epithelial integrity. In situ hybridization confirmed selective localization for the expression of trk B and trk C receptors and Western blot identified a full-length (kinase-active) trk receptor during human kidney development.

Identification of an essential nonneuronal function of neurotrophin 3 in mammalian cardiac development

Neurotrophin 3 (Nt3) is one of five neurotrophin growth factors which shape the development of the nervous system by regulating neuronal survival and differentiation. Peripheral neuronal subpopulations expressing the TrkC receptor tyrosine kinase respond to Nt3 with enhanced survival, mitogenesis or cell migration and these neurons are lost in homozygous Nt3 null (-/-) mutant mice. The unexplained perinatal lethality in the Nt3-/- mice, however, suggests a wider function for this neurotrophin. Here we report that Nt3 is essential for the normal development of atria, ventricles, and cardiac outflow tracts. Histological and echocardiographic image analysis of Nt3-/- animals reveal severe cardiovascular abnormalities including atrial and ventricular septal defects, and tetralogy of Fallot, resembling some of the most common congenital malformations in humans. The observed defects are consistent with abnormalities in the survival and/or migration of cardiac neural crest early in embryogenesis and establish an essential role for neurotrophin 3 in regulating the development of the mammalian heart.

Neurotrophin and neurotrophin receptors in vascular smooth muscle cells. Regulation of expression in response to injury

The neurotrophins, a family of related polypeptide growth factors including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and neurotrophin (NT)-3 and NT-4/5 promote the survival and differentiation of distinctive sets of embryonic neurons. Here we define a new functional role for neurotrophins, as autocrine or local paracrine mediators of vascular smooth muscle cell migration. We have identified neurotrophins, and their cognate receptors, the trk tyrosine kinases, in human and rat vascular smooth muscle cells in vivo. In vitro, cultured human smooth muscle cells express BDNF; NT-3; and trk A, B, and C. Similarly, rat smooth muscle cells expressed all three trk receptors as well as all four neurotrophins. Moreover, NGF induces cultured human smooth muscle cell migration at subnanomolar concentrations. In the rat aortic balloon deendothelialization model of vascular injury, the expression of NGF, BNDF, and their receptors trk A and trk B increased dramatically in the area of injury within 3 days and persisted during the formation of the neointima. In human coronary atherosclerotic lesions, BDNF, NT-3, and NT-4/5, and the trk B and trk C receptors could be demonstrated in smooth muscle cells. These findings suggest that neurotrophins play an important role in regulating the response of vascular smooth muscle cells to injury.

Initial failure strength of open and arthroscopic Bankart repairs

Surgical repair of recurrent anterior shoulder instability requires secure fixation of the separated inferior glenohumeral complex to bone. Many techniques of fixation are in use for both arthroscopic and open repair. The specific aim of this study was to compare the initial failure strength of eight repair techniques using a previously described canine model of Bankart repair. Intact capsule-to-bone complexes failed at the bony interface at 236 N. Traditional Bankart repair failed at 122.1 N (2 sutures) and 74.7 N (1 suture), Acufex TAG rod (Acufex Microsurgical, Mansfield, MA) at 143.5 N (2 sutures) and 79.8 N (1 suture), transglenoid suture technique (2 sutures) at 166.6 N, Mitek GII (Mitek, Norwood, MA) (1 suture) at 96.4 N, Zimmer Statak (Zimmer Inc, Warsaw, IN)(1 suture) at 95.2 N, and Acufex bioasbsorpable Suretac at 82.2 N. The two-suture repairs were statistically equivalent in strength to each other, as were the one-suture repairs and the Suretac device. Two-suture repairs were significantly stronger than the one-suture repairs (P < .01) failure. In the single-suture specimens, failure occurred by suture breakage in 46% (18 of 39) of specimens and soft-tissue failure around the suture in 54% (21 of 39). Failure in the two-suture techniques primarily occurred by soft-tissue failure (23 of 25) and this proved a statistically significant difference (P < .003). No device broke or pulled out of bone.

Solitary nonparasitic cysts of the liver: the Boston Children's Hospital experience

A 3 3/12-year-old female child with abdominal distention, new onset pain, and tenderness is described. The child underwent surgical resection of a multilocular cyst of the right lobe of the liver. We reviewed the autopsy and surgical files of Children's Hospital for the past 63 years to identify other congenital cysts of the liver. We found 30 additional cases including 4 multilocular cysts. The origin of these cysts, a review of the literature, and a discussion of diagnostic parameters for the identification of such cysts in context with other hepatobiliary cystic lesions are presented.

Chromosome aberrations in choroid plexus papillomas

Karyotypic data on choroid plexus papillomas are scarce and, to date, have revealed no consistent aberrations. We karyotyped a choroid plexus papilloma which was characterized by a stemline of 52,XX, + 7, + 11, + 12, + 12, + 15, + 18. Additional copies of chromosomes 16, 17, and 20 were also observed in a significant proportion of the metaphase cells analyzed. Based upon this index case, we retrospectively analyzed eight additional choroid plexus papillomas by fluorescence in situ hybridization by using pericentromeric probes to chromosomes 7, 11, 12, 15, 16, 17, 18, and 20. Extra hybridization signals were observed in five of the eight cases examined. All five cases had extra signals with the chromosome 7 probe, four cases had extra signals with the chromosome 12 probe, and three cases had extra signals with the chromosome 15, 17, and 18 probes. The overall DNA content of these same cases (as determined by image analysis) suggests that gains of additional chromosomes other than those examined may be present.

Identification of the neurotrophin receptors p75 and trk in a series of Wilms' tumors

The molecular mechanisms underlying the pathogenesis of Wilms' tumor (WT) are poorly understood, although a variety of growth factors including platelet-derived growth factor and insulin-like growth factor are expressed and are thought to contribute to tumor development. In earlier studies, WT cells in culture were found to express the low affinity nerve growth factor receptor, p75. These WT cells were capable of responding to the neurotrophin (NT) NGF, suggesting that NT may be involved in WT pathogenesis. We have examined a group of WT immunohistochemically with antibodies recognizing known trk receptor proteins, the p75 receptor, and the NTs, NGF and NT-3. Confirmatory immunoprecipitation and Western blots were then performed on representative WT samples from the study group. The p75 receptor was found predominantly in the epithelial and blastemal components where high levels of NT were also identified. The trk A and B receptors were primarily within stromal components, whereas the trk C and C' receptors were present within epithelial structures. Western blot analyses confirmed the presence of the respective receptor proteins with variations correlating in some cases with histological type. The selective presence of NT receptors and growth factors in this series of WT implies autocrine/paracrine mechanisms for tumor development.

Immunohistochemical localization of Trk receptor protein in pediatric small round blue cell tumors

Expression of Trk protein has been documented by Northern analysis in neuroblastomas with good prognosis. To localize the expression of this protein at the cellular level within individual tumors, we adapted a recently characterized pan-Trk antibody for use in formalin fixed, paraffin-embedded tissue. We have examined a group of small round blue cell tumors occurring in children, including both high and low stage neuroblastomas, to assess the presence or absence of Trk expression and its cellular localization. Positive staining for Trk protein was observed in four of four low stage (good prognosis) neuroblastomas, five of five primitive neuroectodermal tumors/Ewing's sarcoma, five of five rhabdomyosarcomas, and no lymphomas. Within the neuroblastomas, expression of Trk protein was most striking in ganglion cells, in which positive cytoplasmic staining was demonstrated regardless of tumor stage. The latter observation may lend further insight into the pathobiology of this malignant childhood tumor.

Soluble forms of the human T cell receptor CD4 are efficiently expressed by Streptomyces lividans

We have developed a new gene expression and secretion system for Streptomyces lividans and used it to produce soluble forms of a human T-cell receptor CD4 at levels greater than 300 mg/l. The system uses the transcription, translation and secretion signals of the serine protease inhibitor gene STI-II which is naturally produced by S. longisporus. Using these signals, soluble derivatives of CD4 were secreted directly into the culture supernatant as correctly processed soluble, biologically active proteins. High level expression of the CD4 proteins depended on the transcription initiation signal, the amino acid sequence surrounding the signal peptide cleavage site and temporally controlled protease activities. We discuss these results in the context of the potential of this system for producing other eukaryotic proteins in Streptomyces.

The genetic and biochemical basis of polyketide metabolism in microorganisms and its role in drug discovery and development

The possibilities for the design of new drug screening and development strategies directed to a specific objective on the basis of genetic engineering of microorganisms is discussed from two points of view. Firstly, results of work on genetic hybrids of STREPTOMYCES species for the production of new metabolites such as mederrhodin (1) and aloespanoarin II (4) are described. Secondly, the enhanced production of known metabolites such as tetracenomycin A (2) (11) and tetracenomycin C (9) by recombinant STREPTOMYCES species is considered. Mechanistic aspects of polyketide metabolism are included.

The developmental pathology of maternally derived Thp fetuses

The Thair pin (Thp) mutation is a deletion of 5 centimorgans of chromosome 17 in the mouse. When the mutant chromosome is passed to the fetus through the female, the heterozygous fetuses (Thp/+) die in utero. If the chromosome is passed through the male, the heterozygotes are viable and display a short-tailed phenotype. These maternally derived mutant embryos provide an excellent model system to study the effects of an incomplete female genome on development. The results reported here describe the findings of a pathological study of the affected fetuses from day 14 of development to birth. These observations indicate that the maternally derived Thp fetuses die in utero of congestive heart failure. The mutant fetuses displayed an enlarged heart, primarily the right side, and other cardiovascular abnormalities including ventricular septal defects, aortic stenosis, pulmonary artery dilation, and dilation of the venous circulatory system. The fetuses also displayed abnormal accumulation of extrafetal fluid in the visceral yolk sac and amion, as well as massive subcutaneous edema and ascites. The Thp fetuses were often pale and anemic, and they showed a decreased number of red blood cells per unit volume of blood and an increase in circulating nucleated red blood cells. Defects in the development of the labyrinthine and spongiotrophoblast regions of the placenta were also observed. The pathogenesis of the defects is discussed.

The occurrence and distribution of lamin proteins during mammalian spermatogenesis and early embryonic development

Based on current evidence it is apparent that the lamins undergo a dynamic reorganization during both spermatogenesis and early embryonic development, processes that presumably underscore unusual requirements in germ-cell differentiation and embryonic development.

Ultrastructural localization of lysosomal enzymes in the egg cortex of Brachydanio

The localization of acid phosphatase (E.C. 3.1.3.2), inorganic trimetaphosphatase (E.C. 3.6.1.2), and aryl sulfatase (E.C. 3.1.6.1) in the cortex of unactivated and activated eggs of Brachydanio was examined by ultrastructural cytochemistry. Using a lead capture method, activity for all three acid hydrolases was demonstrated in organelles of the cortex before and after egg activation. Acid phosphatase (AcPase) reaction product was consistently present in primary lysosomes, secondary lysosomes, multivesicular bodies, and yolk bodies. AcPase activity was absent from mitochondria, profiles of the endoplasmic reticulum, coated pits of exocytosed cortical granules, and coated vesicles. Although most cortical granules of the mature, unactivated egg were unreactive for this enzyme, a few showed AcPase reaction product. It is not clear whether the AcPase-positive granules might be an immature form of cortical granules or a subpopulation of these organelles with lysosomal properties. Most cisternae of the Golgi apparatus did not stain for AcPase; however, reaction product was occasionally localized in a single cisterna as well as several small vesicles at the inner face of the Golgi. The intensity of the reaction product and the pattern of distribution of trimetaphosphatase (Tm-Pase) activity was very similar to that of AcPase. However, TmPase was never observed in cortical granules. Cortices of unactivated and activated eggs showed less overall aryl sulfatase (ArSase) activity when compared with AcPase and TmPase. The presence of ArSase reaction product in lysosomes and multivesicular bodies confirmed the acid hydrolytic nature of these organelles. AcPase and TmPase, and to a lesser extent ArSase, are adequate markers of a cortical lysosomal system in the danio egg.(ABSTRACT TRUNCATED AT 250 WORDS)