Mapping the Secretome of Dental Pulp Stem Cells Under Variable Microenvironmental Conditions

There is substantial evidence supporting the anti-inflammatory and regenerative potential of dental pulp stem cells (DPSCs) through direct cell transplantation or paracrine action. However, DPSC secretome profile remains inadequately studied. This study provides proteomic profiling of the human DPSC secretome by comparatively analysising cell lysates and respective culture supernatants (i.e. conditioned media-CM) under variable oxygen tension conditions (normoxia-20% O₂/CM_Norm vs. hypoxia 2% O₂/CM_Hyp) and/or stimulation with Tumor Necrosis Factor alpha (TNF-α). DPSC-CM samples and respective crude lysates (DPSC-CL) were collected and subjected to SDS-PAGE, followed by LC-MS/MS analysis. The identified proteins were analyzed by Gene Ontology, Reactome, and String databases. The anti-inflammatory properties of DPSC-CMs were validated via an in vitro RAW_246.7 murine macrophages model through evaluation of the expression of pro-and anti-inflammatory markers by real-time PCR. Results showed a total of 2413 proteins identified in CM_Norm, 2479 in CM_Norm+TNF-α, 1642 in CM_Hyp, and 2002 in CM_Hyp + TNF-α samples. CM_Norm contained 122 proteins statistically significantly upregulated compared to the CM_Hyp and involved in pathways related to "ECM organization", "cellular response to hypoxia", and "IL signaling". Functional network analysis showed that TGFβ1, TIMP1 and TIMP2 were key nodes among proteins significantly upregulated in the CM_Norm compared to the CM_Hyp, interacting with more than 10 proteins, each. DPSC-CM application in the in vitro RAW_246.7 model decreased the expression of pro-inflammatory markers (MMP-3, MMP-9, MMP-13, MCP-1), while increasing anti-inflammatory markers (IL-10). Overall, DPSC-CM collected under normoxic conditions is enriched with anti-inflammatory, tissue repair and regenerative factors, which prompts further investigation on its therapeutic applications.

Angiogenic Activity of Hyperplastic and Neoplastic Lymph Nodes

Angiogenic capacity was tested in 14 non-Hodgkin's lymphomas, 7 Hodgkin's lymphomas and 15 cervical lymph nodes nonneoplastic but draining a territory with a laryngeal carcinoma. The objective was to find out whether different groups of lymphomas showed differences in their angiogenic capacity and to compare the ability to induce neovascularization of neoplastic lymphocytes. Frequency and intensity of the angiogenic response were similar for classes of lymphomas different for morphologic and immunologic characteristics. The presence of a carcinoma was sufficient to induce in tributary, nonmetastatic lymph nodes an angiogenic activity comparable to that known to characterize antigenically stimulated lymphocytes.

Tunable clustering of magnetic nanoparticles in microgels: enhanced magnetic relaxivity by modulation of network architecture

In the present work we used microgels as colloidal containers for the loading of hydrophobic magnetic nanoparticles using the solvent exchange method. We varied systematically two parameters: (i) the crosslinking degree of microgels (1-4.5 mol% crosslinker) and (ii) loading of hydrophobic magnetite nanoparticles (d = 7 nm) in microgels (2-10 wt%). The experimental data show that the interplay between these two parameters provides efficient control over the clustering of magnetic nanoparticles in the microgel structure. Transverse magnetization relaxation measurements indicate that the formation of nanoparticle clusters in microgels induces non-linear enhancement of the relaxivity with the increase of nanoparticle loading in microgels. The results suggest that the modulation of the microgel network architecture can be efficiently applied to trigger self-assembly processes inside microgels and design hybrid colloids with unusual morphologies and properties.

Hydrophobic superparamagnetic FePt nanoparticles in hydrophilic poly(N-vinylcaprolactam) microgels: a new multifunctional hybrid system

We report the synthesis of a new multifunctional colloidal hybrid system consisting of thermoresponsive amphiphilic biocompatible poly(N-vinylcaprolactam) microgels loaded with hydrophobic superparamagnetic FePt nanoparticles (NPs).

Role of the Perivascular Epithelium in the Histogenesis of Hassall's Corpuscles

Thirteen human thymuses and one thymoma were morphologically and immunohistologically investigated to define the histogenesis of Hassall's corpuscles (HCs). The following monoclonal antibodies: antisquamous cytokeratin on paraffin sections and TE-4 and TE-8 on frozen sections, were used to show the distribution of the epithelial components; PAL-E on frozen and anti-CD31 and anti-CD34 on paraffin sections detected the endothelial cell distribution. In the thymoma, epithelial onion-like structures, looking like true HCs, were found to originate from the perivascular epithelium lining dilatated spaces and some of them partially obliterated the space where the blood capillary showed thickened wall and endothelial regressive changes. Antisquamous cytokeratin stained: (1) in the thymus: subcapsular, medullary, and HC epithelial cells; (2) in the thymoma: epithelial cells lining the perivascular spaces and forming HCs. TE-4 stained: (1) in the thymus: the subcapsular and medullary epithelium; (2) in the thymoma: the epithelium lining the perivascular spaces and epithelial cells forming HCs. TE-8 stained: (1) in the thymus: HCs only; (2) in the thymoma: HCs and perivascular epithelial cells. PAL-E, CD31, and CD34, which specifically react with endothelial cells, stained remnants of capillary structures in the core of some HCs. The results indicate that: (1) corpuscular structures in thymoma originate from perivascular epithelium; (2) thymus medullary epithelial cells stained by cytokeratin and TE-4 correspond to perivascular epithelial cells whose staining is well documented in thymoma; (3) the subcapsular-perivascular epithelium and HCs represent different steps of differentiation of a single ectodermal cell lineage; (4) the PAL-E-, CD31-, and CD34-positive reaction in the core of some HCs suggests that the perivascular epithelium would be stimulated to transform into HCs as a consequence of endothelial changes with fragmentation of the capillary included in the perivascular space.

The next step in precipitation polymerization of N-isopropylacrylamide: particle number density control by monochain globule surface charge modulation

Many applications of poly(N-isopropylacrylamide) microgels necessitate robust control over particle size.

Responsive microgels with supramolecular crosslinks: synthesis and triggered degradation in aqueous medium

Stimuli-responsive microgels containing supramolecular crosslinks based on cholesteryl/β-cyclodextrin interactions were synthesized and degraded upon addition of 1-adamantanecarboxylic acid.

QCD and strongly coupled gauge theories: challenges and perspectives

We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.

Differential expression of miR-17~92 identifies BCL2 as a therapeutic target in BCR-ABL-positive B-lineage acute lymphoblastic leukemia

Despite advances in allogeneic stem cell transplantation, BCR-ABL-positive acute lymphoblastic leukaemia (ALL) remains a high-risk disease, necessitating the development of novel treatment strategies. As the known oncomir, miR-17~92, is regulated by BCR-ABL fusion in chronic myeloid leukaemia, we investigated its role in BCR-ABL translocated ALL. miR-17~92-encoded miRNAs were significantly less abundant in BCR-ABL-positive as compared to -negative ALL-cells and overexpression of miR-17~19b triggered apoptosis in a BCR-ABL-dependent manner. Stable isotope labelling of amino acids in culture (SILAC) followed by liquid chromatography and mass spectroscopy (LC-MS) identified several apoptosis-related proteins including Bcl2 as potential targets of miR-17~19b. We validated Bcl2 as a direct target of this miRNA cluster in mice and humans, and, similar to miR-17~19b overexpression, Bcl2-specific RNAi strongly induced apoptosis in BCR-ABL-positive cells. Furthermore, BCR-ABL-positive human ALL cell lines were more sensitive to pharmacological BCL2 inhibition than negative ones. Finally, in a xenograft model using patient-derived leukaemic blasts, real-time, in vivo imaging confirmed pharmacological inhibition of BCL2 as a new therapeutic strategy in BCR-ABL-positive ALL. These data demonstrate the role of miR-17~92 in regulation of apoptosis, and identify BCL2 as a therapeutic target of particular relevance in BCR-ABL-positive ALL.

Poly (vinylcaprolactam)-based Microgels to Improve Gloss Properties of Different Natural Fibres

Three different thermo-sensitive microgels obtained by the copolymerisation of vinylcaprolactam) (VCL) and various monomers (vinylimidazole(VIm), acetoacetoxyethyl methacrylate (AAEM) and itaconic acid(IA)) are used to coat different fibre surfaces. Two different pHs and two different temperatures, 25°C and 50°C respectively are chosen for the deposition of the microgels. The scanning electron microscopy of the treated fibre shows good distribution of the particles onto the fibres especially at increasing temperatures. The gloss index for the treated fibres has been measured, and showed that it may be controlled for all of the fibres with the treatment parameters (pH and temperature) and the microgel structure.

JAK2V617F activating mutation is associated with the myeloproliferative type of chronic myelomonocytic leukaemia

BACKGROUND

Chronic myelomonocytic leukaemia (CMML) is a haematopoietic malignancy with heterogeneous clinical and morphological features. It is classified in the World Health Organization myeloproliferative-myelodysplastic overlap category. JAK2(V617F) mutation can be found in a large percentage of patients with myeloproliferative neoplasms.

AIMS

To investigate the association between JAK2(V617F) mutation and clinical, haematological and bone marrow histological features in CMML and to verify whether the mutation is associated with the myeloproliferative type of the disease.

METHODS

78 consecutive patients with newly diagnosed CMML from 2004 to 2008 were included in the study. JAK2(V617F) mutation was assessed using direct sequencing of exon 14 or by allele-specific PCR from total peripheral blood or bone marrow samples.

RESULTS

JAK2(V617F) mutation was identified in eight cases (10.2%). All patients with the mutation presented with splenomegaly and had a significantly higher haemoglobin level and neutrophil count than patients without the mutation. All bone marrow biopsies of JAK2(V617F)-mutated CMML showed increased erythropoiesis, a marked myeloid and megakaryocytic hyperplasia with occasionally clustered megakaryocytes, and a mild or moderate (grade 1 or 2) fibrosis; six cases showed an increased number of dilated sinusoids and reactive lymphoid nodules.

CONCLUSIONS

The results indicate that JAK2(V617F) mutation is associated with clinical and morphological features of the myeloproliferative type of CMML. Therefore, JAK2 mutation analysis together with bone marrow morphology could help in a more appropriate classification of the disease.

The impact of liquid-based oral cytology on the diagnosis of oral squamous dysplasia and carcinoma

OBJECTIVE

Even though diagnostic oral exfoliative cytology is a useful, economical and practical tool in the diagnosis of oral dysplasia and carcinoma, it is not yet extensively used. The results of conventional exfoliative and liquid-based diagnostic cytology in oral potentially malignant lesions (PML) are herein reported and compared with the histological diagnosis.

METHODS

Either conventional (89) or liquid-based (384) exfoliative cytology was used for the diagnosis of oral dysplasia/carcinoma in 473 subjects and the results were compared with scalpel biopsy histology. Cells were collected using a Cytobrush device for conventional smears and with a dermatological curette for the liquid-based cytology. The 'curette technique' also allowed for the collection of 'accidental' tissue fragments, utilized as microbiopsies.

RESULTS

Histological diagnosis was squamous carcinoma in 96 of 473 cases, high-grade dysplasia (oral intraepithelial neoplasia two to three) in 24 and other lesions in 353 cases. The smears in the conventional cytology group were inadequate in 12.4%, with an 85.7% sensitivity and a 95.9% specificity. There were 8.8% of inadequate specimens in the liquid-based cytology group; sensitivity was 95.1% and specificity was 99.0%.

CONCLUSIONS

Although conventional cytology is useful when diagnosing oral PML (better sensitivity and predictive positive value if compared with the cervical smear test with similar specificity) and can improve the accuracy of histological diagnosis, liquid-based cytology gives better results, as it not only enhances both sensitivity and specificity, but also provides material for further investigation (AgNORs, DNA, microbiopsies, etc.).

Altered chemotherapeutic response of primary human breast cancer epithelial cells (HBCEC) and breast cancer cell lines

11506

Background: A novel technique to obtain individual primary cultures of human breast cancer biopsies was filed for patent (PCT/DE 2006/000608). The different individualized HBCEC (human breast cancer epithelial cell) cultures will be characterized and chemotherapeutic effects will be compared to established breast cancer cell lines. Methods: Primary HBCEC from 20 different breast cancer patients were characterized for epithelial cell and tumor markers by immunofluorescence and PCR. Following treatment with 1μM epirubicin for 1h up to 72h differences in protein expression patterns were compared to the similarly treated MCF-7 cell line by 2D gel electrophoresis. Differentially expressed protein spots were identified by mass spectrometry and confirmed by appropriate Western blot analysis. Results: Characterization of primary HBCEC revealed continuous mitosis and cell cycle progression for more than one year in culture with no significant contamination by fibroblasts or other cell types. Whereby HBCEC underwent cell death within 72h of epirubicin treatment analysis by 2D gel and subsequent protein identification by MALDI-TOF/TOF mass spectrometry exhibited a variety of differences compared to MCF-7 cells including HSP27 and prohibitin. Appropriate Western blots confirmed these differences and revealed altered expression levels for HSP27 and prohibitin in the course of epirubicin exposure in HBCEC and MCF-7 cells, respectively, suggesting altered signalling pathways in either primary breast cancer cells or the tumor cell line. Conclusions: Individualized primary HBCEC from various patients could provide a cellular platform beyond breast cancer cell lines, which eventually meet the requirements for an appropriate breast cancer testing system including the characterization of biomarkers and the identification of potential molecular targets.

No significant financial relationships to disclose.

Redispergation of TiO2 particles in aqueous solutions

The colloidal stability of TiO2 dispersions in aqueous solutions was studied. Aqueous solutions of ATLAS G-3300 (1.57 x 10(-3) mol/l), TRITON X-100 (5 x 10(-5) mol/l), and PMAA (4 x 10(-6) and 5.81 x 10(-3) mol/l) have been used as medium for redispergation of TiO2 particles. Stability of dispersions was investigated at different pH values by two different methods. By using analytical centrifuge the sedimentation velocity of TiO2 particles was directly measured and by means of light scattering the particle size of dispersed particles has been monitored. Combination of these two methods allowed determination of the aggregation degree of TiO2 particles as well as structure of the aggregates formed in aqueous phase. It has been found that redispergation process does not provide complete separation of virgin TiO2 particles. Even in the case of stable dispersions some aggregates were found, which consisted of 2-4 virgin TiO2 particles. With increasing colloidal stability of dispersions aggregates appear to be spherically shaped. In the system where TRITON X-100 was used, formation of secondary aggregates by fusion of primary ones was observed.

Prognostic relevance of cell proliferation in head and neck tumors

Cell proliferative activity has been extensively investigated in head and neck tumors. Ki67/MIB-1 immunostaining, tritiated thymidine or bromodeoxyuridine labeling indices, DNA S-phase fraction, proliferating cell nuclear antigen expression, potential doubling time and analysis of the nucleolar organizer region associated proteins (AgNORs) have shown significant correlation with prognosis in 4806 cases of tumors of the oral cavity, salivary glands, pharynx and larynx. However, this was not observed in 2968 other reported cases. Discrepancies may depend on various factors: the heterogeneity of the series, which include tumors from various anatomic sites and patients treated with different therapy, and the lack of standardization of methods for assessing cell proliferation. Furthermore, none of the methods currently applied can by themselves define the actual proliferative activity, as it depends both on the proportion of cells committed to the cycle (growth fraction) and the speed of the cell cycle. Indeed, the actual proliferative activity of a tumor could well be measured by the equation [PA = Ki67 or MIB-1 scores x AgNORs], as we did in pharyngeal carcinoma. Provided that large and homogeneous series are evaluated by standardized methods, cell proliferative activity can still be regarded as an inexpensive and reliable prognostic factor in head and neck tumors.

[Usefulness of oral exfoliative cytology for the diagnosis of oral squamous dysplasia and carcinoma]

AIM

It is well known that diagnostic oral exfoliative cytology, even if a useful, economical and practical tool in the diagnosis of oral dysplasia and carcinoma, is not yet used so extensively as is cervico-vaginal cytology.

METHODS

Exfoliative cytology was used for the diagnosis of oral dysplasia and carcinoma, and the results compared to the histological examination. Cytological smears were taken from 89 patients with oral lesions suspicious for neoplasia (in particular erythro- and leukoplakia and lichen). All patients were also subjected to oral biopsy and histological examination.

RESULTS

Out of 89 cases studied, histology showed the presence of an invasive squamous carcinoma in 32, dysplasia in 17, phlogosis in 15 and other types of lesions (2 of which malignant non-epithelial tumours) in 25. The cytological smear was inadequate for diagnosis in 11/89 cases (12.4%). In cytologically adequate and histologically positive cases, cytology confirmed the histological diagnosis of dysplasia and/or carcinoma in 38/45 cases (sensitivity 86.5%, accuracy 89.6%). Moreover, 1 case which was histologically negative at the onset, proved positive at cytology. There were 2 false-positive cytology results (specificity 94.3%, predictive positive value 95.7%).

CONCLUSIONS

Despite the small number of cases in the cohort, oral cytology can improve the accuracy of histology, and may be a useful screening tool for the diagnosis of oral neoplasia/dysplasia.

Isospin violation in epsilon'

On the basis of a next-to-leading-order calculation in chiral perturbation theory, the first complete analysis of isospin breaking for direct CP violation in K0-->2 pi decays is performed. We find a destructive interference between three different sources of isospin violation in the CP violation parameter epsilon'. Within the uncertainties of large-N(c) estimates for the low-energy constants, the isospin violating correction for epsilon' is below 15%.

[LAT (linker for activation of T cells): a useful marker for megakaryocyte evaluation on bone marrow biopsies]

Detection of atypical megakaryocytes in bone marrow biopsies, especially in cases of myelodysplastic syndromes (MDS), chronic myeloproliferative disorders (CMPD) and acute leukemias, is facilitated by staining for markers such as Ulex europaeus agglutinin (UEA)-J, CD31, CD61 and von Willebrand factor (VWF), the latter being considered the most sensitive. Recently, LAT (linker for activation of T cells), a molecule involved in T-cell activation and platelet aggregation, was found to be expressed by megakaryocytes and platelets in tissue sections. We compared VWF and LAT immunoreactivity on megakaryocytes in 64 bone marrow biopsies from 12 normal controls (NC), and from patients with MDS (n=18), CMPD (n=21) and acute megakaryocytic leukemia (AML-M7, n=13). Immunostaining was performed on paraffin sections with polyclonal antibodies against VWF and LAT. Immunoreactivity was evaluated by counting positive megakaryocytes in 10 high-power fields, and values were compared using Student's t test for paired data. Both VWF and LAT predominantly stained the cytoplasm of megakaryocytes, although LAT was also recognizable on the cell membrane. In most biopsies, the immunoreactivity of the two antibodies was quite similar. No significant differences were noticed between the mean values of VWF+ and LAT+ megakaryocytes. However, in 22 cases (5 NC; 5 MDS; 6 CMPD; 6 AML-M7), the number of LAT+ megakaryocytes was at least 30% higher than VWF+cells, while in 3 cases opposite findings were found. In 3 AML-M7 cases, anti-LAT antibodies stained numerous megakaryocytes, but anti-VWF staining was practically negative; in another 5 AML-M7 cases, anti-LAT labeling was much stronger than anti-VWF staining. LAT represents a useful immunohistochemical marker for megakaryocytes in normal and pathological conditions. It seems to be expressed by megakaryocytes more than VWF in most cases and, particularly, in conditions associated with poorly differentiated megakaryocytes, such as acute megakaryocytic leukemias. The use of LAT staining should be recommended in association with other megakaryocyte markers in the study of bone marrow biopsies in cases of hematopoietic disorders.

[Significance of the AgNOR in tumor pathology]

Analysis of silver-stained nucleolar organizer regions (AgNORs), originally regarded as a diagnostic tool, is now considered mainly as a prognostic parameter. Indeed, the expression of AgNOR proteins is associated with several biological properties of neoplastic cells: metabolic activity, DNA content, histological grade of differentiation and, especially, the rapidity of cellular proliferation. Thus, a high AgNOR quantity is a marker of aggressive tumour phenotype, and a large number of papers have shown the independent prognostic value of AgNOR analysis in several human neoplasias. Moreover, the method can be applied to small biopsies, can identify neoplastic clones with different proliferative activities and may stratify patients into different risk groups. The standardized method for AgNOR quantification offers objective and reproducible results. The evaluation of AgNOR quantity in cycling cells, either by immunohistochemistry or by a novel flow cytometry technique, may represent the future of AgNOR analysis.

Biologic differences between noninvasive papillary urothelial neoplasms of low malignant potential and low-grade (grade 1) papillary carcinomas of the bladder

We investigated the expression of oncogenes p53, c-erbB-2, and bcl-2 and cell proliferative activity in 62 newly diagnosed superficial pTa papillary bladder tumors. Based on the 1998 World Health Organization/International Society of Urological Pathology (WHO/ISUP) and 1999 WHO classifications, 19 were urothelial neoplasias of low malignant potential (LMP) and 43 low-grade (grade 1) papillary carcinomas. All the patients underwent transurethral resection and were followed up to 97 months; 42 had recurrences. Initial biopsies were tested for p53, c-erbB-2, and bcl-2 proteins using DO7, CB11, and bcl-2 124 monoclonal antibodies. Cell proliferation was assessed by MIB-1 mAb and mitotic count. LMP had significantly lower MIB-1 (p = 0.002) and p53 immunopositivity (p = 0.03), mitotic count (p = 0.006), and recurrence rates (p = 0.04) than did grade 1 cases, whereas no difference was observed for c-erbB-2 and bcl-2 expression. The median disease-free survival for LMP was 76 months but only 15 months for grade 1 cases (p = 0.002). Although the cohort is small, the results indicate that the distinction between LMP and low-grade (grade 1) papillary urothelial neoplasias, as proposed by the 1998 WHO/ISUP and 1999 WHO classifications, reflects different biologic activity and clinical behavior; however, a long-term follow-up is advisable also for patients with LMP.

Fe homeostasis in plant cells: does nicotianamine play multiple roles in the regulation of cytoplasmic Fe concentration?

The cellular and intracellular localization of the non-proteogenic amino acid nicotianamine (NA) in leaves and root elongation zones was immunochemically investigated in pea (Pisum sativum L.) and tomato (Lycopersicon esculentum Mill.) plants grown under various iron regimes and in three mutants defective in the regulation of iron uptake. Strongest immunostaining was observed in the over-accumulating pea mutants brz and dgl, and in iron-loaded wild-type plants. Fe concentration and NA level paralleled staining intensity, indicating that NA synthesis is induced by high iron availability. While label was mainly present in the cytoplasm under normal (10 microM) Fe supply and under Fe deprivation, most of the labeling was present in the vacuole in iron-loaded plants. This pattern resembled the distribution of NA in Fe over-accumulating mutants, indicating the possible importance of vacuolar sequestration in the detoxification of excess Fe. Based on the dependence of the cellular distribution of NA on the iron nutritional status of the plant, a possible role of NA in buffering free Fe in root and leaf cells was inferred. We show here for the first time that the NA concentration is increased in response to iron overload, indicating that, besides other classes of intracellular metal-binding ligands, NA may play an essential role in iron tolerance.

Tungstate Uptake by a highly specific ABC transporter in Eubacterium acidaminophilum

The Gram-positive anaerobe Eubacterium acidaminophilum contains at least two tungsten-dependent enzymes: viologen-dependent formate dehydrogenase and aldehyde dehydrogenase. (185)W-Labeled tungstate was taken up by this organism with a maximum rate of 0.53 pmol min(-)1 mg(-)1 of protein at 36 degrees C. The uptake was not affected by equimolar amounts of molybdate. The genes tupABC coding for an ABC transporter specific for tungstate were cloned in the downstream region of genes encoding a tungsten-containing formate dehydrogenase. The substrate-binding protein, TupA, of this putative transporter was overexpressed in Escherichia coli, and its binding properties toward oxyanions were determined by a native polyacrylamide gel retardation assay. Only tungstate induced a shift of TupA mobility, suggesting that only this anion was specifically bound by TupA. If molybdate and sulfate were added in high molar excess (>1000-fold), they were also slightly bound by TupA. The K(d) value for tungstate was determined to be 0.5 microm. The genes encoding the tungstate-specific ABC transporter exhibited highest similarities to putative transporters from Methanobacterium thermoautotrophicum, Haloferax volcanii, Vibrio cholerae, and Campylobacter jejuni. These five transporters represent a separate phylogenetic group of oxyanion ABC transporters as evident from analysis of the deduced amino acid sequences of the binding proteins. Downstream of the tupABC genes, the genes moeA, moeA-1, moaA, and a truncated moaC have been identified by sequence comparison of the deduced amino acid sequences. They should participate in the biosynthesis of the pterin cofactor that is present in molybdenum- and tungsten-containing enzymes except nitrogenase.

In vitro processing of the proproteins GrdE of protein B of glycine reductase and PrdA of D-proline reductase from Clostridium sticklandii: formation of a pyruvoyl group from a cysteine residue

GrdE and PrdA of Clostridium sticklandii are subunits of glycine reductase and D-proline reductase, respectively, that are processed post-translationally to form a catalytic active pyruvoyl group. The cleavage occurred on the N-terminal side of a cysteine residue, which is thus the precursor of a pyruvoyl moiety. Both proproteins could be over-expressed in Escherichia coli and conditions were developed for in vitro processing. GrdE could be expressed as full-size protein, whereas PrdA had to be truncated N-terminally to achieve successful over-expression. Both proproteins were cleaved at the in vivo observed cleavage site after addition of 200 mM NaBH4 in Tris buffer (pH 7.6) at room temperature as analysed by SDS/PAGE and MS. Cleavage of GrdE was observed with a half-time of approximately 30 min. Cys242, as the precursor of the pyruvoyl group in GrdE, was changed to alanine, serine, or threonine by site-directed mutagenesis. The Cys242-->Ser and Cys242-->Thr mutant proteins were also cleaved under similar conditions with extended half-times. However, the Cys242-->Ala mutant protein was not cleaved indicating a pivotal role of the thiol group of cysteine or hydroxyl group of serine and threonine during the processing of pyruvoyl group-dependent reductases.

Molecular analysis of the grd operon coding for genes of the glycine reductase and of the thioredoxin system from Clostridium sticklandii

A probe based on the sequence of the gene encoding selenoprotein A of glycine reductase of Clostridium sticklandii was used to obtain clones of adjacent DNA that encoded the other components of glycine reductase, proteins B and C, in addition to thioredoxin and thioredoxin reductase. The genes of the thioredoxin system and the glycine reductase were shown to be transcribed together, confirming an operon structure. In addition, a gene (grdX) encoding a 13.7-kDa protein of unknown function seemed to be associated with the reductase genes. Four potential promoters were identified by mapping the 5'-end of the mRNAs. The sequence of promoter P1 was shown to be similar to the sigma70 promoter consensus sequence. The other three promoters were similar to each other, but not to known promoter consensus sequences. The transcripts starting at each of the four promoters were terminated to about 80% at a predicted loop structure downstream of grdB; the remaining transcripts continued through this structure and covered the genes encoding both subunits of protein C and bmpA, a gene that was also expressed monocistronically.

Nuclear morphometry in male breast carcinoma: association with cell proliferative activity, oncogene expression, DNA content and prognosis

To investigate the prognostic value of nuclear morphometry in male breast carcinoma (MBC), histological samples from 50 patients (mean age 62.2 years) were retrospectively analyzed by computerized nuclear morphometry. All patients received surgery; 35 had multiple combinations of adjuvant therapies. Mean follow-up was 67 months (range 1-230). In each case, 100 tumor cells were measured, and the mean nuclear area (MNA), standard deviation of the nuclear area (SDNA), mean nuclear perimeter (MNP), standard deviation of the nuclear perimeter (SDNP) and shape factor (SHF) were calculated. Morphometric features were compared with tumor histological grade, size, nodal status, DNA ploidy evaluated by flow-cytometry and cell proliferative activity assessed by the quantity of argyrophilic nucleolar organizer region-associated proteins (AgNORs), monoclonal antibody (MAb) PC10 against proliferating cell nuclear antigen and MAb MIB-1. Comparison was also made with the immunohistochemical detection of p53, bcl-2, c-erbB-2 and c-myc proteins. Significant association was found between nuclear morphometric parameters and tumor grade, DNA content and cell proliferation indices. SDNA was greater in p53-positive and bcl-2-negative cases; SDNP was greater in p53-positive cases; SHF was lower in p53- and c-myc-positive cases. Overall survival was shorter in carcinomas with high MNA, SDNA, MNP and SDNP and low SHF. In multivariate analysis, performed by testing nuclear morphometric parameters, histological grade, tumor size, nodal status and p53 immunostaining in the Cox model, p53 over-expression and histological grade retained independent prognostic significance. When p53 was excluded, only SDNP appeared as an independent prognostic variable. Our results indicate that nuclear morphometric parameters can identify an aggressive tumor phenotype and provide additional prognostic information for patients with MBC.

Therapy and survival in male breast carcinoma: A retrospective analysis of 50 cases

The relationship between therapy and overall survival was retrospectively investigated in 50 patients with primary male breast carcinoma. Forty-five had radical or modified radical mastectomy and 5 simple mastectomy. Thirty-five received adjuvant post-operative therapy, including radiation, hormone and chemotherapy, given separately or in combination. The mean follow-up period was 67 (range, 1-230) months. The median survival was 33 months for patients receiving surgery alone and 86 months for those who also had adjuvant therapy (p=0.003). No difference in survival was found between simple or radical/modified radical mastectomy, nor among the various types of adjuvant therapy. Adjuvant therapy was most effective in large size, node positive and poorly differentiated tumors, and retained independent prognostic significance in multivariate analysis. With the limitation due to the small number of cases, our data suggest that adjuvant therapy may improve survival in males with cancer of the breast.

Oncogenes and male breast carcinoma: c-erbB-2 and p53 coexpression predicts a poor survival

PURPOSE

To investigate the prognostic value of biomarkers in male breast carcinoma (MBC).

PATIENTS AND METHODS

Fifty patients (mean age, 62.2 years) with invasive ductal carcinoma were retrospectively studied. All patients received surgery; 35 had adjuvant postoperative therapy. The median follow-up was 59 months (range, 1 to 230 months). c-myc, c-erbB-2, p53, and bcl-2 proteins were immunohistochemically detected on sections from formalin-fixed, paraffin-embedded tissues using 9E11, CB11, DO7, and bcl-2 124 monoclonal antibodies (mAbs). Estrogen, progesterone, and androgen receptors were detected using specific mAbs. Cell proliferation was assessed by MIB-1 mAb.

RESULTS

In univariate analysis, c-myc, c-erbB-2, and p53 protein overexpression was significantly correlated with prognosis. The median survival was 107 months for c-myc-negative and 52 months for c-myc-positive patients (P =.01), 96 months for c-erbB-2-negative and 39 months for c-erbB-2-positive patients (P =.02), and 100 months for p53-negative and 33 months for p53-positive patients (P =.0008). Tumor histologic grade (P =.01), tumor size (P =.02), patient age at diagnosis (P =.03), and MIB-1 scores (P =.0004) also had prognostic value. In multivariate analysis, only c-erbB-2 and p53 immunoreactivity retained independent prognostic significance. All nine patients who did not express c-erbB-2 and p53 proteins were alive after 58 months, whereas none of the 14 patients expressing both proteins survived at 61 months follow-up (P =.0002).

CONCLUSION

Overexpression of c-myc, c-erbB-2, and p53 proteins may be regarded as an additional prognostic factor in MBC. The combination of c-erbB-2 and p53 immunoreactivity can stratify patients into different risk groups.

Partial purification of an iron-dependent L-serine dehydratase from Clostridium sticklandii

An oxygen-sensitive and highly unstable L-serine dehydratase was partially purified from the Gram-positive anaerobe Clostridium sticklandii. The final active preparation contained five proteins of 27, 30, 44.5, 46, and 58 kDa as judged by SDS-PAGE. The N-terminal sequence of the 30 kDa subunit showed some similarity to the alpha-subunits of the iron-containing L-serine dehydratases from Clostridium propionicum and Peptostreptococcus asaccharolyticus. Oxygen-inactivated L-serine dehydratase from C. sticklandii was reactivated by incubation with Fe2+ under reducing conditions. Furthermore, the enzyme was inactivated by iron-chelating substances like phenanthroline and EDTA. Pyridoxal-5-phosphate (PLP) did not stimulate the activity, and known inhibitors of PLP-containing enzymes such as NaBH4 had no effect on the activity of L-serine dehydratase from C. sticklandii.