Signaling Pathways in the Relapse of Glioblastoma.

BACKGROUND: Glioblastoma is the most common primary neoplasm of the central nervous system. Standard treatment includes surgery with maximum safe resection and radiotherapy plus concomitant and adjuvant chemotherapy; however, almost invariably, tumor relapse occurs. We aimed to describe signaling pathways and molecular mechanisms present in tumor relapse of glioblastoma. METHODS: This systematic review followed the PRISMA guidelines. We searched the PubMed, EMBASE and Web of Science databases. We included studies that enrolled patients 15 years or older with a diagnosis of glioblastoma according to Louis criteria and focused on signaling pathways and molecular mechanisms present in tumor relapse of glioblastoma. The outcome of interest was progression-free survival. RESULTS: We identified 1470 articles; 31 met the inclusion criteria. From each publication, we obtained the associated markers O-6-methylguanine-DNA methyltransferase, isocitrate dehydrogenase, mRNA, epidermal growth factor receptor (EGFR), p53, and others. All publications were evaluated with the Q-Genie checklist tool for quality assessment. CONCLUSIONS: We identified a wide variety of signaling pathways and molecular processes that are involved in glioblastoma relapse. This diversity would explain intra- and intertumor heterogeneity, treatment evasion, and relapse. However, only a few molecular processes have robust evidence for clinical utility.

Intravascular (blood vessel) histiocytosis with haemophagocytosis.

AIMS: Many types of intravascular lymphohistiocytic proliferation have been described recently; this was previously an unnoticed or misinterpreted phenomenon. Intralymphatic lymphohistiocytic aggregates are relatively common, and include benign, malignant and indeterminate conditions. In contrast, all non-endothelial proliferations in the lumina of blood vessels have been interpreted so far as malignant. Herein, we present three cases of histiocytic proliferations in the lumen of blood vessels associated with intracytoplasmic granulocyte debris (haemophagocytosis), a previously undescribed entity. METHODS AND RESULTS: We identified three patients from two institutions with similar cutaneous lesions, both clinically and microscopically. Information regarding clinical history, histological features and immunoprofiles were obtained. The three cases presented intravascular histiocytosis with haemophagocytosis involving blood vessels of the dermis, a process that may be representative of a new entity. The patients were two women and one man who presented a symmetrical reticulated erythema with a tendency to involve the skin of the breasts. The lesions were indolent, did not ulcerate and followed a benign course. CONCLUSION: This seemingly novel condition is characterized by the presence of histiocytic cells inside blood vessels, where they have not been described previously as an entity. The most reasonable explanation for this process is an origin from the non-classical subset of monocytes that 'patrol' the inner face of blood vessels acting as macrophages. The existence of this entity should be kept in mind to avoid overdiagnosis of malignancy.

GBA Mutations Are Associated With Earlier Onset and Male Sex in Dementia With Lewy Bodies.

BACKGROUND: Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are Lewy body diseases characterized by similar pathological features. Several studies have shown a relation between alterations in the glucocerebrosidase gene (GBA) and the development of LB diseases. Here, we explored the role of GBA mutations in Spanish DLB patients. METHODS: GBA mRNA sequences were analyzed in a neuropathological (50 DLB, 43 PD, and 34 control brains) and in a clinical cohort (47 DLB patients and 131 unaffected individuals). RESULTS: Sixteen GBA mutation carriers were identified, 5 of which were brains with pure DLB. The most common mutation, E326K, was strongly associated with pure DLB and PD with dementia. GBA mutations were overrepresented in men and associated with earlier DLB onset. CONCLUSIONS: GBA mutations are also an important risk factor for DLB development in the Spanish population, are associated with earlier disease onset, and are more prevalent in men. © 2015 International Parkinson and Movement Disorder Society.

Cystatin C is differentially involved in multiple system atrophy phenotypes.

AIMS: As cystatin C (CysC) is involved in some forms of neurodegeneration, we investigated the possible relationship between CysC and multiple system atrophy (MSA), including its parkinsonian (MSAp) and cerebellar (MSAc) phenotypes. METHODS: Cystatin C gene (CST3) haplotypes were determined by PCR followed by KspI digestion in 50 MSA patients and 108 controls. CST3 and cathepsins B, D and L1 mRNA levels were studied in frozen post-mortem caudate nucleus and cerebellar samples of eight MSAp, four MSAc and 18 control brains and analysed by the ΔΔCt method. CysC immunohistochemistry was performed on three MSAp, three MSAc and three control cerebella. Additionally, determination of CST3 and cathepsins B, D and L1 mRNA levels and immunohistochemistry for CysC were carried out in cerebella from three patients with paraneoplastic cerebellar degeneration, three with spinocerebellar ataxia (type 3, SCA3) and three with cerebellar ischaemia (CI). RESULTS: In the set of blood samples, the CST3 B-haplotype was associated with MSAp (OR 4.86, confidence interval 1.84-13.3). High CST3 mRNA levels were found in MSAp caudate nuclei [expression change: 3.08 (2.98-3.18)] and MSAc cerebella [expression change: 2.44 (2.14-2.88)]. In the latter there was CysC over-expression in Purkinje cells, Bergmann glia and dentate nucleus neurones. No cathepsin increase was detected in MSA cerebella. High mRNA levels of CST3 and cathepsins B and L1 were observed in SCA3 and CI brains. CONCLUSIONS: CysC changes are differentially present in the parkinsonian and cerebellar forms of MSA and may play an important role in the pathogenesis of this neurodegenerative condition.

Human SMC2 protein, a core subunit of human condensin complex, is a novel transcriptional target of the WNT signaling pathway and a new therapeutic target.

Human SMC2 is part of the condensin complex, which is responsible for tightly packaging replicated genomic DNA prior to segregation into daughter cells. Engagement of the WNT signaling pathway is known to have a mitogenic effect on cells, but relatively little is known about WNT interaction with mitotic structural organizer proteins. In this work, we described the novel transcriptional regulation of SMC2 protein by direct binding of the ß-catenin·TCF4 transcription factor to the SMC2 promoter. Furthermore, we identified the precise region in the SMC2 promoter that is required for ß-catenin-mediated promoter activation. Finally, we explored the functional significance of down-regulating SMC2 protein in vivo. Treatment of WNT-activated intestinal tumor cells with SMC2 siRNA significantly reduced cell proliferation in nude mice, compared with untreated controls (p = 0.02). Therefore, we propose that WNT signaling can directly activate SMC2 transcription as a key player in the mitotic cell division machinery. Furthermore, SMC2 represents a new target for oncological therapeutic intervention.

MYC status determination in aggressive B-cell lymphoma: the impact of FISH probe selection.

AIMS: To assess how hybridization probe design may affect MYC status determination in Burkitt lymphoma and diffuse large B-cell lymphoma. METHODS AND RESULTS: We compared the results obtained with one dual-fusion and two break-apart commercial probes in a retrospective series of 91 aggressive B-cell lymphomas. All three probes were able to detect the IGH-MYC translocation in every case bearing it (13/13). However, seven of 13 (54%) non-IGH-MYC (light-chain immunoglobulin or non-immunoglobulin-MYC) rearrangements were unambiguously detected by just one of the probes tested. On the other hand, when the IGH-MYC dual-fusion probe was used, nine of 15 (60%) cases with a hybridization pattern suggestive of a non-IGH-MYC translocation were attributable to MYC copy gain rather than MYC rearrangement, as demonstrated by both break-apart probes. CONCLUSIONS: Taking into account the prognostic and therapeutic implications of the MYC translocation, probe design and limitations should be particularly kept in mind when MYC hybridization patterns are interpreted. In our experience, detection of 8q24 abnormalities could be optimized by a two-probe approach involving the application of both IGH-MYC dual-fusion and MYC break-apart selected kits.

Cutaneous presentation of chronic lymphocytic leukemia as unique extramedullar involvement in a patient with normal peripheral blood lymphocyte count (monoclonal B-cell lymphocytosis).

Skin infiltration by chronic lymphocytic leukemia (CLL) is very rare and almost all reported cases occur in advanced stage. We report a patient with no relevant past medical history who presented with cutaneous erythematous plaques. A punch biopsy showed typical CLL morphologic and immunophenotypic features. Subsequent studies revealed a normal lymphocyte count in peripheral blood, and there was no evidence of lymphadenopathy or organomegaly. Flow cytometry demonstrated a clonal B-cell population both in the bone marrow and peripheral blood (1.60 × 10(9)/l) with a CLL phenotype, but it did not fulfill required criteria for CLL diagnosis. Without cutaneous involvement, this case should be classified as monoclonal B-cell lymphocytosis.

New brain-specific beta-synuclein isoforms show expression ratio changes in Lewy body diseases.

Lewy body diseases (LBDs) include dementia with Lewy bodies (DLB) and Parkinson disease (PD). Alpha-synuclein (AS) aggregation is a key event in the pathogenesis of LBDs and beta-synuclein (BS) inhibits AS aggregation in vitro and in vivo. Recently, BS has been shown to interact directly with AS regulating its functionality and preventing its oligomerization, and a molecular subgroup of pure DLB lacks BS in cortical regions. In this study, we characterized four new BS transcript variants and analyzed their expression in neuronal and non-neuronal tissue, and their differential expression in frozen samples of three areas from brains of patients with pure Lewy body pathology (LBP), common LBP, Alzheimer pathology, and of controls. Relative mRNA expression was determined by real-time PCR with neuron-specific enolase 2 and synaptophysin as housekeeping genes, and expression changes were evaluated by the ΔΔCt method. Two main findings are in concordance with earlier studies. First, all BS isoforms are drastically diminished in the cortex of patients with pure LBP that had presented clinically as DLB but not PD with dementia. Second, an important shift of the isoform expression ratio was observed in the temporal cortex of all LBD cases, and the minor isoforms, normally absent in the midbrain, were detected in the caudate nucleus of all DLB samples. Our results provide further evidence for the role of minor transcript variants in the development of complex diseases and provide new insights into the pathogenesis of LBDs that may be important for the understanding of molecular mechanisms involved in these complex diseases.

Improved clonality detection in Hodgkin lymphoma using the BIOMED-2-based heavy and kappa chain assay: a paraffin-embedded tissue study.

AIMS: Although BIOMED-2 polymerase chain reaction (PCR) standardization protocols allow clonality detection in nearly 100% of non-Hodgkin B cell lymphomas, they have not been widely validated for Hodgkin lymphoma (HL). Our aim was to assess BIOMED-2 protocol sensitivity when using non-microdissected, formalin-fixed, paraffin-embedded (FFPE) tissue from HL cases. METHODS AND RESULTS: We studied 69 consecutive HL cases, of which 61 corresponded to classic HL (cHL) and eight to nodular lymphocyte-predominant HL (NLPHL). CD30-positive cell numbers (<10, 10-25 or >25 per ×200 field), background CD20-positive cell density (low or high) and tumour cell immunophenotype were evaluated. IGH and IGK clonality was assessed on FFPE tissue following BIOMED-2 protocols. Of the 58 assessable cHL cases, 15 (25.9%) exhibited IGH and/or IGK clonality; IGH clonality was shown by nine (15.5%) and IGK clonality by 12 (20.7%). Clonality detection rates in cHL improved as CD30-positive Reed-Sternberg (RS) cell density increased and CD20-positive B cell density decreased, although these correlations did not reach statistical significance. Of the eight NLPHL cases studied, none showed clonal rearrangement. CONCLUSIONS: Combined study of IGH and IGK rearrangement according to BIOMED-2 protocols improves clonality detection rate (up to 25% of cases) in HL, even when working on non-microdissected FFPE tissue.

[The Alliance for the Prevention of Colorectal Cancer in Spain. A civil commitment to society]. / Alianza para la Prevención del Cáncer de Colon en España: un compromiso cívico con la sociedad.

Colorectal cancer (CRC) is the most common malignant tumor in Spain, when men and women are considered together, and the second leading cause of cancer death. Every week in Spain over 500 cases of CRC are diagnosed, and nearly 260 people die from the disease. Epidemiologic estimations for the coming years show a significant increase in the number of annual cases. CRC is a perfectly preventable tumor and can be cured in 90% of cases if detected in the early stages. Population-based screening programs have been shown to reduce the incidence of CRC and mortality from the disease. Unless early detection programs are established in Spain, it is estimated that in the coming years, 1 out of 20 men and 1 out of 30 women will develop CRC before the age of 75. The Alliance for the Prevention of Colorectal Cancer in Spain is an independent and non-profit organization created in 2008 that integrates patients' associations, altruistic non-governmental organizations and scientific societies. Its main objective is to raise awareness and disseminate information on the social and healthcare importance of CRC in Spain and to promote screening measures, early detection and prevention programs. Health professionals, scientific societies, healthcare institutions and civil society should be sensitized to this highly important health problem that requires the participation of all sectors of society. The early detection of CRC is an issue that affects the whole of society and therefore it is imperative for all sectors to work together.

Prevalence of HPV-DNA and E6 mRNA in lung cancer of HIV-infected patients.

HIV-infected individuals could be at a greater risk for developing lung cancer than the general population due to the higher prevalence in the former of human papillomavirus (HPV) in the oral cavity and higher smoking rates. Our aim was to assess HPV prevalence and E6 viral oncogene transcription in lung cancer samples from HIV-infected individuals. This was a single-center, retrospective study of a cohort of HIV-1-infected patients diagnosed with and treated for lung cancer. Pathological lung samples archived as smears or formalin-fixed paraffin-embedded blocks were subjected to HPV genotyping, detection of human p16 protein and assessment for HPV E6 mRNA expression. Lung cancer samples from 41 patients were studied, including squamous cell carcinoma (32%), adenocarcinoma (34%), non-small cell cancer (27%), and small cell cancer (7%). HPV DNA was detected in 23 out of 41 (56%, 95% CI 41-70%) of samples and high-risk (HR)-HPV types were detected in 16 out of 41 (39%, 95% CI 26-54%), HPV-16 being the most prevalent [13/16 (81.3%, 95% CI 57.0-93%]. In samples with sufficient material left: expression of p16 was detected in 3 out of 10 (30%) of HR-HPV DNA-positive tumors and in 3 out of 7 (43%) of the negative ones; and E6 mRNA was detected in 2 out of 10 (20%) of HPV-16-positive samples (squamous lung cancers). These two patients had a background of a previous HPV-related neoplasia and smoking. HR-HPV DNA detection was prevalent in lung cancers in HIV-infected patients. However, viral oncogene expression was limited to patients with previous HPV-related cancers.

Voices from the past: results of the ESP history of pathology working group survey on pathology museums.

While keeping their original purpose of training medical students, pathology museums hold great biological value, offering unique specimens for scientific research through modern radiological, pathological and biomolecular techniques. Moreover, the artefacts, models and drawings displayed in these museums are a precious cultural and artistic heritage. Preservation of the anatomical samples and maintenance of the facilities are neither easy nor inexpensive and call for patronage. The development of a European Pathology Museum Network would undoubtedly facilitate study, access and divulgation of antique pathology collections. Data from a survey conducted by the European Society of Pathology (ESP) History of Pathology Working Group have allowed creation of a comprehensive, multifaceted portrait of European university museums, reflecting their history, diversity, geography, institutional status, stakeholders, projects, professionals, audiences, policies and best practices.

Immunohistochemical detection of MYC protein correlates with MYC gene status in aggressive B cell lymphomas.

AIMS: MYC gene translocation entails a bad prognosis and a poor response to rituximab-cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) in diffuse large B cell lymphomas (DLBCL), and more intensive chemotherapy regimens could be more effective in those cases. Its evaluation requires cytogenetic or fluorescence in-situ hybridization (FISH) studies, which are expensive and not widely available. The aim of this work was to find an immunohistochemical marker able to be used as a screening tool to identify MYC translocations. METHODS AND RESULTS: Aggressive B cell lymphomas in which MYC status was assessed during their diagnostic work-up between 2007 and 2010 were collected, their immunophenotype was re-evaluated, and were stratified according to the Hans algorithm. Two tissue microarrays were built in order to evaluate MYC protein expression with a commercially available antibody. The study was performed on 56 specimens: nine Burkitt lymphomas (eight translocated), 45 DLBCLs (nine translocated) and two lymphomas with intermediate features (both translocated). Only MYC protein expression detected by immunohistochemistry correlated with MYC translocation. No relationship was seen between MYC gene copies and protein expression. CONCLUSIONS: MYC protein expression detected by immunohistochemistry using a commercially available antibody correlates with MYC gene translocation, and could be used as a screening tool to select those cases in which confirmatory genetic testing is mandatory.

The decrease of ß-synuclein in cortical brain areas defines a molecular subgroup of dementia with Lewy bodies.

Lewy body diseases include dementia with Lewy bodies and Parkinson's disease. Whereas dementia with Lewy bodies and Parkinson's disease can be distinguished as separate clinical entities, the pathological picture is very often identical. α-synuclein aggregation is a key event in the pathogenesis of Lewy body diseases and ß-synuclein inhibits α-synuclein aggregation in vitro and in vivo. Recently, ß-synuclein has been shown to interact directly with α-synuclein, regulating its functionality and preventing its oligomerization. In this study, we analysed the expression of two ß-synuclein transcript variants and the main α-synuclein transcript SNCA140, in frozen samples of three areas from brains of patients with (i) pure diffuse Lewy body pathology; (ii) pure Alzheimer's disease pathology; (iii) diffuse Lewy body pathology and concomitant Alzheimer's disease pathology and (iv) controls. Relative messenger RNA expression was determined by real-time polymerase chain reaction, expression changes were evaluated by the ΔΔC(t) method and messenger RNA expression data were confirmed at the protein level. A drastic diminution of ß-synuclein expression was observed in cortical areas of all samples that presented neuropathological features corresponding to pure diffuse Lewy body pathology and the clinical phenotype of dementia with Lewy bodies, but not in those with neuropathological features corresponding to diffuse Lewy body pathology and concomitant Alzheimer's disease pathology or the clinical phenotype of Parkinson's disease with dementia. The correlation of expression data with the clinical phenotype and neuropathological diagnosis of the patients suggested the existence of a specific molecular subtype of dementia with Lewy bodies, characterized by a strong decrease of ß-synuclein in the frontal and temporal cortices. Furthermore, our findings provide new insights into the pathogenesis of Lewy body diseases that may be important for the understanding of molecular mechanisms involved in these complex diseases.

Grover disease: a reappraisal of histopathological diagnostic criteria in 120 cases.

Grover disease (GD) is a rather common papular pruritic dermatosis that can be transient, persistent, or asymptomatic. The microscopic diagnosis of clinically suspected lesions can be challenging because GD can adopt different patterns, and involved areas are generally admitted to be mostly focal. The histopathologic hallmark of the disease is acantholysis, frequently combined with dyskeratosis, which confers the lesions an appearance similar to Darier disease, Hailey-Hailey disease, or pemphigus. Eczematous features can be observed as well. In this study of 120 consecutive cases of GD, we have found a sex and age incidence similar to what has been previously described, with no obvious seasonal influence, but careful evaluation of their microscopic features suggests that the histopathological diagnostic criteria of GD should be expanded. Specifically, in addition to the commonly described GD findings, we have detected cases with porokeratosis-like oblique columns of parakeratosis, lesions showing a nevoid or lentiginous silhouette, intraepidermal vesicular lesions, lichenoid changes with basal vacuolization and dyskeratosis, and dysmaturative foci with keratinocyte atypia. Moreover, quite often the dermal infiltrate was composed not only of lymphocytes intermingled with eosinophils, but also of neutrophils. In many cases, the capillary vessels showed hints of vascular damage including endothelial tumefaction due to cytoplasmatic edema and erythrocyte extravasation. Finally, because involved areas were larger than 2 mm in more than 50% of our cases, we should assume that GD lesions are not always as small as commonly claimed. Awareness of the patterns newly described herein may be important to avoid underdiagnosis of GD and may contribute to understand the pathogenesis of this acantholytic disease.

Multisite and bidirectional exonic splicing enhancer in CD44 alternative exon v3.

The human CD44 gene encodes multiple isoforms of a transmembrane protein that differ in their extracellular domains as a result of alternative splicing of its variable exons. Expression of CD44 is tightly regulated according to the type and physiological status of a cell, with expression of high molecular weight isoforms by inclusion of variable exons and low molecular weight isoforms containing few or no variable exons. Human CD44 variable exon 3 (v3) can follow a specific alternative splicing route different from that affecting other variable exons. Here we map and functionally describe the splicing enhancer element within CD44 exon v3 which regulates its inclusion in the final mRNA. The v3 splicing enhancer is a multisite bipartite element consisting of a tandem nonamer, the XX motif, and an heptamer, the Y motif, located centrally in the exon. Each of the three sites of this multisite enhancer partially retains its splicing enhancing capacity independently from each other in CD44 and shows full enhancing function in gene contexts different from CD44. We further demonstrate that these motifs act cooperatively as at least two motifs are needed to maintain exon inclusion. Their action is differential with respect to the splice-site target abutting v3. The first X motif acts on the 3' splice site, the second X motif acts on both splice sites (as a bidirectional exonic splicing enhancer), and the Y motif acts on the 5' splice site. We also show that the multisite v3 splicing enhancer is functional irrespective of flanking intron length and spatial organization within v3.

Molecular pathology of Lewy body diseases.

Lewy body diseases are characterized by the presence of Lewy bodies, alpha-synuclein(AS)-positive inclusions in the brain. Since their main component is conformationally modified AS, aggregation of the latter is thought to be a key pathogenic event in these diseases. The analysis of inclusion body constituents gives additional information about pathways also involved in the pathology of synucleinopathies. Widespread mitochondrial dysfunction is very closely related to disease development. The impairment of protein degradation pathways, including both the ubiquitin-proteasome system and the autophagy-lysosome pathway also play an important role during the development of Lewy body diseases. Finally, differential expression changes of isoforms corresponding to genes primarily involved in Lewy body formation point to alternative splicing as another important mechanism in the development of Parkinson's disease, as well as dementia with Lewy bodies. The present paper attempts to give an overview of recent molecular findings related to the pathogenesis of Lewy body diseases.