Investigation on PLK2 and PLK3 substrate recognition.

Analyses of human phosphoproteome based on primary structure of the aminoacids surrounding the phosphor Ser/Thr suggest that a significant proportion of phosphosites is generated by a restricted number of acidophilic kinases, among which protein kinase CK2 plays a prominent role. Recently, new acidophilic kinases belonging to the Polo like kinase family have been characterized, with special reference to PLK1, PLK2, and PLK3 kinases. While some progress has been made in deciphering the PLK1-dependent phosphoproteome, very little is known about the targets of PLK2 and PLK3 kinases. In this report by using an in vitro approach, consisting of cell lysate phosphorylation, phosphoprotein separation by 2D gel electrophoresis and mass spectrometry, we describe the identification of new potential substrates of PLK2 and PLK3 kinases. We have identified and validated as in vitro PLK2 and PLK3 substrates HSP90, GRP-94, ß-tubulin, calumenin, and 14-3-3 epsilon. The phosphosites generated by PLK3 in these proteins have been identified by mass spectrometry analysis to get new insights about PLKs specificity determinants. These latter have been further corroborated by an in silico analysis of the PLKs substrate binding region.

An unusual case of melanoma metastasis in the buccal space: learning by mistakes to distinguish it from salivary neoplasms.

BACKGROUND: The buccal space is an unusual location of malignancies. We report here the case of a woman with a melanoma metastasis in buccal fat pad, to evaluate the imaging features which might lead to the correct, although uncommon, diagnosis. CASE PRESENTATION: A 71-year-old woman presented with a painless visible swelling of the left cheek. MRI revealed the presence of a solid lesion located in the buccal fat pad with features suggestive of malignancy. It showed T1 hyperintensity and T2 hypointensity, and restriction of diffusion. Histological examination showed neoplastic cells compatible with melanoma. DISCUSSION: The lesion features (T1 hyperintensity and T2 hypointensity) initially lead our team to believe that there was a hemorrhagic component, possibly a residue of the biopsy. However, when associated with other malignancy features, such as low apparent diffusion coefficient (ADC) values and contrast enhancement, they should evoke the suspect of melanoma, provided that no biopsy was performed and no trauma occurred in the 3-7 days before.

The high mobility group (HMG) boxes of the nuclear protein HMG1 induce chemotaxis and cytoskeleton reorganization in rat smooth muscle cells.

HMG1 (high mobility group 1) is a ubiquitous and abundant chromatin component. However, HMG1 can be secreted by activated macrophages and monocytes, and can act as a mediator of inflammation and endotoxic lethality. Here we document a role of extracellular HMG1 in cell migration. HMG1 (and its individual DNA-binding domains) stimulated migration of rat smooth muscle cells in chemotaxis, chemokinesis, and wound healing assays. HMG1 induced rapid and transient changes of cell shape, and actin cytoskeleton reorganization leading to an elongated polarized morphology typical of motile cells. These effects were inhibited by antibodies directed against the receptor of advanced glycation endproducts, indicating that the receptor of advanced glycation endproducts is the receptor mediating the HMG1-dependent migratory responses. Pertussis toxin and the mitogen-activated protein kinase kinase inhibitor PD98059 also blocked HMG1-induced rat smooth muscle cell migration, suggesting that a G(i/o) protein and mitogen-activated protein kinases are required for the HMG1 signaling pathway. We also show that HMG1 can be released by damage or necrosis of a variety of cell types, including endothelial cells. Thus, HMG1 has all the hallmarks of a molecule that can promote atherosclerosis and restenosis after vascular damage.

Identification of CXCL13 as a new marker for follicular dendritic cell sarcoma.

The homeostatic chemokine CXCL13 is preferentially produced in B-follicles and is crucial in the lymphoid organ development by attracting B-lymphocytes that express its selective receptor CXCR5. Follicular dendritic cells (FDCs) have been identified as the main cellular source of this chemokine in lymphoid organs. Recently, genome-wide approaches have suggested follicular CD4 T-helper cells (T(H)F) as additional CXCL13 producers in the germinal centre and the neoplastic counterpart of T(H)F (CD4+ tumour T-cells in angioimmunoblastic T-cell lymphoma) retains the capability of producing this chemokine. In contrast, no data are available on CXCL13 expression on FDC sarcoma (FDC-S) cells. By using multiple approaches, we investigated the expression of CXCL13 at mRNA and protein level in reactive and neoplastic FDCs. In reactive lymph nodes and tonsils, CXCL13 protein is mainly expressed by a subset of FDCs in B-cell follicles. CXCL13 is maintained during FDC transformation, since both dysplastic FDCs from 13 cases of Castleman's disease and neoplastic FDCs from ten cases of FDC-S strongly and diffusely express this chemokine. This observation was confirmed at mRNA level by using RT-PCR and in situ hybridization. Of note, no CXCL13 reactivity was observed in a cohort of epithelial and mesenchymal neoplasms potentially mimicking FDC-S. FDC-S are commonly associated with a dense intratumoural inflammatory infiltrate and immunohistochemistry showed that these lymphocytes express the CXCL13 receptor CXCR5 and are mainly of mantle zone B-cell derivation (IgD+ and TCL1+). In conclusion, this study demonstrates that CXCL13 is produced by dysplastic and neoplastic FDCs and can be instrumental in recruiting intratumoural CXCR5+ lymphocytes. In addition to the potential biological relevance of this expression, the use of reagents directed against CXCL13 can be useful to properly identify the origin of spindle cell and epithelioid neoplasms.

Spontaneous pneumothorax in cocaine users.

BACKGROUND: Pneumothorax is one of the respiratory toxic effects of cocaine inhalation. The literature counts several cases, some associated to other respiratory conditions such as pneumomediastinum, haemoptysis and others not requiring surgical treatment. AIM: We present a series of nonHIV cocaine-inhaler subjects who underwent video-assisted thoracoscopic surgery (VATS) for isolated spontaneous pneumothorax. DESIGN: Nine subjects, with a mean age of 24 ± 4 years, admitting cocaine inhalation, developed spontaneous pneumothorax and underwent 10 surgical treatments by means of VATS, at our Institution. RESULTS: Previous pneumothorax occurred in six cases episodes ranged from 0 to 5 (mean 1.6 ± 1.6). Chest computed tomography (CT) scan showed abnormalities in seven cases. All subjects underwent lung apicectomy, apical pleurectomy and mechanical pleurodesis. Seven subjects had also bullectomy. In all cases the visceral pleura was partially covered by fibrinous exudate. Histology of the lung showed small foreign body granulomatous inflammation in fibrotic and/or emphysematous pulmonary parenchyma. Relapse of pneumothorax occurred in one subject at 60 days and it was surgically treated. Mean follow-up was 150 ± 38 months (range 120-239). All subjects are now well, with no evidence of pneumothorax. CONCLUSIONS: Spontaneous pneumothorax in cocaine-inhaler subjects is a reality of which physicians need to be aware. Chest CT scan might not reveal abnormalities. Macroscopically the lung might presents bullae and/or peculiar visceral pleura. Foreign body granulomas observed in the specimens suggest that the particulate component of inhaled substances can injure the lung. Surgical treatment of the bullous disease and mechanical pleurodesis can provide a long-term follow-up without relapse of pneumothorax.

The C-C chemokine receptors CCR4 and CCR8 identify airway T cells of allergen-challenged atopic asthmatics.

In vitro polarized human Th2 cells preferentially express the chemokine receptors CCR3, CCR4, and CCR8 and migrate to their ligands: eotaxin, monocyte-derived chemokine (MDC), thymus- and activation-regulated chemokine (TARC), and I-309. We have studied the expression of chemokines and chemokine receptors in the airway mucosa of atopic asthmatics. Immunofluorescent analysis of endobronchial biopsies from six asthmatics, taken 24 hours after allergen challenge, demonstrates that virtually all T cells express IL-4 and CCR4. CCR8 is coexpressed with CCR4 on 28% of the T cells, while CCR3 is expressed on eosinophils but not on T cells. Expression of the CCR4-specific ligands MDC and TARC is strongly upregulated on airway epithelial cells upon allergen challenge, suggesting an involvement of this receptor/ligand axis in the regulation of lymphocyte recruitment into the asthmatic bronchi. In contrast to asthma, T cells infiltrating the airways of patients with chronic obstructive pulmonary disease and pulmonary sarcoidosis produce IFN-gamma and express high levels of CXCR3, while lacking CCR4 and CCR8 expression. These data support the role of CCR4, of its ligands MDC and TARC, and of CCR8 in the pathogenesis of allergen-induced late asthmatic responses and suggest that these molecules could be considered as targets for therapeutic intervention.

A case of endobronchial paraganglioma.

Paragangliomas are rare lung tumours; endobronchial localisation is even more rare. This report describes the case of a 59-year-old patient with a symptomatic endobronchial paraganglioma successfully resected by means of pulmonary lobectomy. Recognition of this uncommon tumour can lead to a correct diagnosis and therapeutic strategy.

Proteome Analysis of Urticating Setae From Thaumetopoea pityocampa (Lepidoptera: Notodontidae).

Thaumetopoea pityocampa (Denis & Schiffermüller) (Lepidoptera: Notodontidae) is harmful to conifer trees because of defoliation and to public health because of the release of urticating setae from the caterpillars. Contact with setae by humans and domestic animals induces dermatitis, usually localized to the exposed areas. Recent studies demonstrated the presence of a complex urticating mechanism where proteins present in the setae may play a role as activators of immune responses. Yet, limited information is available at present about the proteins occurring in the setae of T. pityocampa. Using a refined method for protein extraction from the setae, and a combination of liquid chromatography tandem-mass spectrometry (LC-MS/MS), de novo assembly of transcriptomic data, and sequence similarity searches, an extensive data set of 353 proteins was obtained. These were further categorized by molecular function, biological process, and cellular location. All the 353 proteins identified were found to match through BLAST search with at least one Lepidoptera sequence available in databases. We found the previously known allergens Tha p 1 and Tha p 2 described from T. pityocampa, as well as enzymes involved in chitin biosynthesis, one of the principal components of the setae, and serine proteases that were responsible for inflammatory and allergic reactions in other urticating Lepidoptera. This new proteomic database may allow for a better understanding of the complexity of allergenic reactions due to T. pityocampa and to other Lepidoptera sharing similar defense systems.

Protein kinase CK2 phosphorylates and upregulates Akt/PKB.

Treatment of Jurkat cells with specific inhibitors of protein kinase CK2 induces apoptosis. Here we provide evidence that the anti-apoptotic effect of CK2 can be at least partially mediated by upregulation of the Akt/PKB pathway. Such a conclusion is based on the following observations: (1) inhibition of CK2 by cell treatment with two structurally unrelated CK2 inhibitors induces downregulation of Akt/PKB, as judged from decreased phosphorylation of its physiological targets, and immunoprecipitate kinase assay; (2) similar results are observed upon reduction of CK2 catalytic subunit by the RNA-interference technique; (3) Akt/PKB Ser129 is phosphorylated by CK2 in vitro and in vivo; (4) such a phosphorylation of activated Akt/PKB correlates with a further increase in catalytic activity. These data disclose an unanticipated mechanism by which constitutive phosphorylation by CK2 may be required for maximal activation of Akt/PKB.

Leaf apoplastic proteome composition in UV-B treated Arabidopsis thaliana mutants impaired in extracellular glutathione degradation.

In plants, environmental perturbations often result in oxidative reactions in the apoplastic space, which are counteracted for by enzymatic and non-enzymatic antioxidative systems, including ascorbate and glutathione. However, the occurrence of the latter and its exact role in the extracellular space are not well documented. In Arabidopsis thaliana, the gamma-glutamyl transferase isoform GGT1 bound to the cell wall takes part in the so-called gamma-glutamyl cycle for extracellular glutathione degradation and recovery, and may be implicated in redox sensing and balance. In this work, oxidative conditions were imposed with UV-B radiation and studied in redox altered ggt1 mutants. Elevated UV-B has detrimental effects on plant metabolism, plasma membranes representing a major target for ROS generated by this harmful radiation. The response of ggt1 knockout Arabidopsis leaves to UV-B radiation was assessed by investigating changes in apoplastic protein composition. We then compared the expression changes resulting from the mutation and from the UV-B treatment. Rearrangements occurring in apoplastic protein composition suggest the involvement of hydrogen peroxide, which may ultimately act as a signal. Other important changes related to hormonal effects, cell wall remodeling, and redox activities are also reported. We argue that oxidative stress conditions imposed by UV-B and by disruption of the gamma-glutamyl cycle result in similar stress-induced responses, to some degree at least. Data shown here are associated with the article from Trentin et al. (2015) [1]; protein data have been deposited to the PRIDE database (Vizcaíno et al., 2014) [2] with identifier PXD001807.

Amplification and overexpression of PRUNE in human sarcomas and breast carcinomas-a possible mechanism for altering the nm23-H1 activity.

PRUNE, the human homologue of the Drosophila gene, is located in 1q21.3, a region highly amplified in human sarcomas, malignant tumours of mesenchymal origin. Prune protein interacts with the metastasis suppressor nm23-H1, but shows impaired affinity towards the nm23-H1 S120G mutant associated with advanced neuroblastoma. Based on these observations, we previously suggested that prune may act as a negative regulator of nm23-H1 activity. We found amplification of PRUNE in aggressive sarcoma subtypes, such as leiomyosarcomas and malignant fibrous histiocytomas (MFH) as well as in the less malignant liposarcomas. PRUNE amplification was generally accompanied by high mRNA and moderate to high protein levels. The sarcoma samples expressed nm23-H1 mostly at low or moderate levels, whereas mRNA and protein levels were moderate to high in breast carcinomas. For the more aggressive sarcoma subtypes, 9/13 patients with PRUNE amplification developed metastases. A similar situation was observed in all breast carcinomas with amplification of PRUNE. Infection of NIH3T3 cells with a PRUNE recombinant retrovirus increased cell proliferation. Possibly, amplification and overexpression of PRUNE has the same effect in the tumours. We suggest that amplification and overexpression of PRUNE could be a mechanism for inhibition of nm23-H1 activity that affect the development or progression of these tumours.

Lack of CD 29 (beta1 integrin) and CD 54 (ICAM-1) adhesion molecules in intravascular lymphomatosis.

Intravascular Lymphomatosis (IL) is a rare and usually aggressive form of non-Hodgkin's lymphoma characterized by the growth of neoplastic cells within vascular lumina that usually presents with skin or central nervous system (CNS) involvement. The mechanism(s) for the selective intravascular growth of this neoplasm remain(s) unexplained. We now report clinical and immunohistologic data on surgical material from 6 cases of IL; in 4 of 6 cases, autopsies were performed. Our IL cases shared the following features: (1) B-cell lineage; (2) lack of skin involvement at presentation; (3) aggressive behavior; and (4) lack of extravascular lymphomatous masses; in addition, 1 case had an associated gastric low-grade MALT lymphoma. We studied by immunohistochemistry formalin-fixed, paraffin-embedded sections with monoclonal antibodies to molecules known to be involved in lymphocyte and endothelial adhesion phenomena, that is, CD29 (beta1 integrin subunit), CD43 (leukosialin), CD44 (H-CAM), CD54 (ICAM-1), embryonal N-CAM (e-NCAM), and EMA (episialin). In all cases, the surfaces of IL aggregates reacted for CD44 but were consistently negative for CD29; also absent was CD54. Conversely, the integrity of the endothelial cells was underscored by their even reactivity for CD29, CD44, and CD54. Given that CD29 is currently regarded as critical for lymphocyte trafficking in general and for transvascular migration in particular, and CD54 is also involved in transvascular lymphocyte migration, we conclude that their consistent absence in IL may contribute to its intravascular and disseminated distribution pattern. The rather frequent association of IL with various conventional lymphomas is known; yet, one of our cases appears to be the first report of IL associated with a low-grade MALT lymphoma.

Diagnostic and therapeutic management of neuroendocrine lung tumors: a clinical study of 44 cases.

Neuroendocrine tumors of the lung (NTL) are a distinct subset of tumors with a wide range of histological patterns and clinical behavior. Controversy still exists as to the ideal diagnostic and therapeutic approach to these neoplasms. A series of 44 consecutive NTL patients operated on at our Institution was retrospectively reviewed in order to critically analyze the diagnostic and therapeutic management. A preoperative diagnosis was obtained in 11 patients (25%). All patients underwent an anatomical surgical resection with lymphoadenectomy. Pathological diagnosis was typical carcinoid (TC) tumor in 36 cases, atypical carcinoid (AC) in three and large-cell neuroendocrine carcinoma (LCNEC) in five. One patient had preoperative chemotherapy. Node-positive patients received postoperative radiotherapy on the mediastinal area. Median follow-up time was 40 months for TC and 51.5 months for AC/LCNEC. Recurrence of disease was observed in three patients with TC and in two with AC/LCNEC. Actuarial 5-year survival was 93% for TC and 70% for AC/LCNEC. Survival was not influenced by tumor size, while lymph node metastases were associated with a worse prognosis. However, due to the limited number of patients, no statistical significance was observed. In conclusion, our study confirms findings in the literature showing that TC and AC/LCNEC are clinically different, and that a differential preoperative diagnosis and treatment is necessary. Although the results of new diagnostic techniques such as octreotide scintigraphy are encouraging, they need to be validated in a larger number of patients. Surgery, with anatomical resection and lymphoadenectomy, remains the treatment of choice in all these tumors. Laser treatment should be considered only as a palliative procedure or as a complementary technique to surgery. The role of adjuvant treatments in AC and LCNEC is uncertain and should be evaluated in larger trials. The prognostic role of biological factors such as cytometry and genetic markers requires further investigation before any definitive conclusions can be drawn.

p53 protein expression in central nervous system neoplasms.

AIMS: To demonstrate, immunohistochemically, p53 protein expression in a selection of central nervous system tumours; to investigate the relation between p53 expression and that of the proliferation related antigen, PCNA. METHODS: Surgical specimens from 86 central nervous system tumours were routinely fixed, paraffin wax embedded, and immunostained with a monoclonal (PAb 1801) and a policlonal antibody (CM1) p53 protein and a monoclonal antibody against PCNA (PC10). Normal brain samples obtained at necropsy and 10 surgically obtained samples of gliotic brain parenchyma were also immunostained. RESULTS: p53 protein expression was observed in 35 of 86 brain tumours, suggesting frequent p53 gene mutation. p53 protein alterations were associated with all grades of malignancy in tumours displaying solely astrocytic differentiation, with the exception of pilocytic astrocytomas. In those showing oligodendroglial or ependymal differentiation they appeared to be restricted almost to only high grade lesions. No p53 immunoreactivity was observed in normal or gliotic brain tissue; p53 altered expression was not related to the percentage of PCNA labelled cells. CONCLUSIONS: The use of sophisticated gene amplification techniques or highly sensitive immunohistochemical methods might be useful in distinguishing between reactive and neoplastic astrocytic lesions, and in the identification of malignant progression in other non-astrocytic glial tumours. Tumours with very similar histogenetic differentiation features might actually be a genetically heterogeneous group with possible different clinical courses.

Mediastinal dumbbell angiolipoma.

Nonneurogenic dumbbell tumors are rare. This report describes the case of a 46-year-old woman with a symptomatic mediastinal dumbbell angiolipoma. The tumor was successfully resected using a single-stage procedure, combining a posterior microneurosurgical and thoracoscopic approach. The patient made an uneventful recovery and the neurologic symptoms improved immediately.

Cytogenetics of multiple endocrine neoplasia syndromes. I. Two different, unique clonal chromosome changes in a medullary thyroid carcinoma and in a C-cell thyroid hyperplasia.

In short-term cultures of tumor tissue from a medullary thyroid carcinoma (MTC), we found a large clone of cells with a balanced translocation t(9;12)(p24;q22). A large clone with a balanced translocation t(10;16)(p11;q24) was also found in cultures from a C-cell thyroid hyperplasia. No clearcut evidence for chromosome instability was observed in the lymphocytes of the two patients. The mother of the first patient died of MTC; two relatives of the second patient had MTC and one of them had pheochromocytoma. These findings classify the two subjects as MEN 2A patients with different phenotypic expression but with the same type of chromosomal abnormality.

Longitudinal transgastric echocardiographic views utilizing a single-plane probe: anatomic correlations and clinical applications.

In order to widen the diagnostic capability of single-plane transesophageal echocardiography, which has been so far confined to transverse imaging planes, we obtained four transgastric longitudinal echocardiographic views which have not been previously described. These views can image structures such as superior and inferior vena cava, the right ventricular inflow and outflow tract, the mitral apparatus and the ascending aorta, which are poorly visualized by transesophageal transverse single-plane echocardiography. Among 400 consecutive patients these scans gave relevant additional diagnostic information in 62 cases (15.5%) and provided the correct diagnosis in 37 (9.2%). There were no complications related to the longer gastric manipulation of the probe and the quality of the images was high. We conclude that longitudinal echotomographic scanning of the heart is not exclusively confined to the use of biplane or omniplane probes, but longitudinal views can be consistently obtained with a single-plane instrument.

Evaluation of radiological and pathological prognostic factors in surgically-treated patients with bronchoalveolar carcinoma.

OBJECTIVE: The incidence of adenocarcinoma and bronchoalveolar carcinoma has increased in recent years. The aim of this study was to retrospectively evaluate radiological and pathological factors affecting survival in patients with bronchoalveolar carcinoma (BAC) or BAC associated with adenocarcinoma who underwent surgical treatment. METHODS: From May 1988 to September 1999, 49 patients with BAC or BAC and adenocarcinoma underwent surgical treatment. Complete resection was performed in 42 patients. In these patients the impact of the following factors on survival was evaluated: stage, TNM status, radiological and pathological findings (percentage of bronchoalveolar carcinoma in the tumour, presence or absence of sclerosing and mucinous patterns, vascular invasion and lymphocytic infiltration). RESULTS: Twenty-nine patients were male and 20 female. Mean age was 63 years. Five-year survival was 54%. Univariate analysis of the patients who underwent complete resection demonstrated a favourable impact on survival in stages Ia and Ib (P = 0.01) and in the absence of nodal involvement (P = 0.02) and mucinous patterns (P = 0.02). Mucinous pattern was also prognostically relevant at multivariate analysis (P = 0.02). In the 27 patients with stage Ia and Ib disease, univariate analysis demonstrated that the absence of mucinous pattern (P = 0.006) and a higher percentage of BAC (P = 0.01) favourably influenced survival. The latter data were also confirmed by multivariate analysis (P = 0.01). CONCLUSION: Surgical treatment of early-stage BAC and combined BAC and adenocarcinoma is associated with favourable results. However, the definition of prognostic factors is of utmost importance to improve the results of the treatment. In our series tumours of the mucinous subtype and with a lower percentage of BAC had a worse prognosis.

Bronchial carcinoids with S-100 positive sustentacular cells. A comparative study with gastrointestinal carcinoids, pheochromocytomas and paragangliomas.

Fourty-six bronchial carcinoids, twelve tumourlets and twenty areas of neuroendocrine cell dysplasia (NED) were immunohistochemically evaluated for various neuroendocrine markers, S-100 protein (S-100), myelin basic protein, intermediate filaments, actin, Leu-7 and several neurohormonal polypeptides. Eighteen of the bronchial carcinoids (39.1%) showed a biphasic cell pattern, with abundant stellate-shaped S-100 positive cells (SC). SC were not reactive for chromogranin A, myelin basic protein, cytokeratins, neurofilaments, glial fibrillary acidic protein or actin, and were only occasionally weakly positive for vimentin. SC were not detected in the tumourlets nor in the NED observed. For comparison a group of other neuroendocrine tumours (11 gastrointestinal carcinoids, 4 pheochromocytomas and 4 paragangliomas) were immunostained for S-100, chromogranin A and actin. SC similar to the ones detected in the bronchial carcinoids could be detected in appendiceal carcinoids, paragangliomas and in two out of four pheochromocytomas. Our present data are in keeping with a Schwannian/sustentacular nature of SC rather than that of a histiocytic or myoepithelial nature. We suggest that SC-rich bronchial carcinoids are biphasic tumours, which could be designed "paraganglioid" bronchial carcinoids. The relationship between SC-rich bronchial carcinoids and tumourlets/NED is a matter of further investigation: SC-rich bronchial carcinoids may either differentiate in a biphasic pattern during tumoural growth or may not be histogenetically related to tumourlets.