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MDM2 amplification represents the leading oncogenic pathway and diagnostic hallmark of liposarcoma, whose assessment is based on Fluorescence In Situ Hybridization (FISH) analysis. Despite its diagnostic relevance, no univocal interpretation criteria regarding FISH assessments of MDM2 amplification have been established so far, leading to several different approaches and potential diagnostic misinterpretations. This study aims to address the most common issues and proposes troubleshooting guidelines for MDM2 amplification assessments by FISH. We retrospectively retrieved 51 liposarcomas, 25 Lipomas, 5 Spindle Cell Lipoma/Pleomorphic Lipomas, and 2 Atypical Spindle Cell Lipomatous Tumors and the corresponding MDM2 FISH analysis. We observed MDM2 amplification in liposarcomas cases only (43 out of 51 cases) and identified three MDM2-amplified patterns (scattered (50% of cases), clustered (14% of cases), and mixed (36% of cases)) and two nonamplified patterns (low number of signals (82% of cases) and polysomic (18% of cases)). Based on these data and published evidence in the literature, we propose a set of criteria to guide MDM2 amplification analysis in liposarcoma. Kindled by the compelling importance of MDM2 assessments to improve diagnostic and therapeutic liposarcoma management, these suggestions could represent the first step to develop a univocal interpretation model and consensus guidelines.

Nature Communications 8: Article number: 14797 (2017); Published online 16 March 2017; Updated 30 March 2018 In the original version of this Article, the affiliation details for Anna Sapino were incorrectly given as Department of Medical Sciences, University of Torino, 10126 Torino, Italy instead ofCandiolo Cancer Institute-FPO, IRCCS, Str.

Brain metastases develop in one-third of patients with non-small-cell lung cancer and are associated with a dismal prognosis, irrespective of surgery or chemo-radiotherapy. Pathological markers for predicting outcomes after surgical resection and radiotherapy responsiveness are still lacking. Caveolin 1 has been associated with chemo- and radioresistance in various tumors, including non-small-cell lung cancer. Here, caveolin 1 expression was assessed in a series of 69 brain metastases from non-small-cell lung cancer and matched primary tumors to determine its role in predicting survival and radiotherapy responsiveness. Only caveolin 1 expression in brain metastasis was associated with poor prognosis and an increased risk of death (log rank test, p = 0.015). Moreover, in the younger patients (median age of

The docking protein p140Cap negatively regulates tumour cell features. Its relevance on breast cancer patient survival, as well as its ability to counteract relevant cancer signalling pathways, are not fully understood. Here we report that in patients with ERBB2-amplified breast cancer, a p140Cap-positive status associates with a significantly lower probability of developing a distant event, and a clear difference in survival. p140Cap dampens ERBB2-positive tumour cell progression, impairing tumour onset and growth in the NeuT mouse model, and counteracting epithelial mesenchymal transition, resulting in decreased metastasis formation. One major mechanism is the ability of p140Cap to interfere with ERBB2-dependent activation of Rac GTPase-controlled circuitries. Our findings point to a specific role of p140Cap in curbing the aggressiveness of ERBB2-amplified breast cancers and suggest that, due to its ability to impinge on specific molecular pathways, p140Cap may represent a predictive biomarker of response to targeted anti-ERBB2 therapies., p140Cap adaptor proteins interfere with adhesion and growth factor-dependent signalling in cancer cells but the mechanisms are unclear. Here the authors show that p140Cap interferes with ERBB2-dependent activation of Rac GTPase-controlled circuitries reducing metastasis and cancer progression.

Background Immunohistochemistry (IHC) and fluorescent-in situ hybridization (FISH) are standard methods to assess human epidermal growth factor receptor 2 (HER2) status in breast cancer (BC) patients. Real-time quantitative polymerase-chain-reaction (qRT-PCR) is able to detect HER2 overexpression. Here we compared FISH, IHC, quantitative PCR (qPCR), and qRT-PCR to determine the concordance rates and evaluate their relative roles in HER2 determination. Patients and methods We determined HER2 status in 153 BC patients, using IHC, FISH, Q-PCR and qRT-PCR. In discordant cases, we directly measured HER2 protein levels using Western blotting. Results The overall agreement (OA) between FISH and Q-PCR was 94.1, with a k value of 0.87. Assuming FISH as the standard reference, Q-PCR showed an 86.1% sensitivity and a 99.0% specificity with a global accuracy of 91.6%. OA between FISH and qRT-PCR was 90.8% with a k value of 0.81. Of interest, the disagreement between FISH and qRT-PCR was mostly restricted to equivocal cases. HER2 protein analysis suggested that qRT-PCR correlates better than FISH with HER2 protein levels, particularly where FISH fails to provide conclusive results. Significance qRT-PCR may outperform FISH in identifying patients overexpressing HER2 protein. Q-PCR cannot be used for HER2 status assessment, due to its suboptimal level of agreement with FISH. Both FISH and Q-PCR may be less accurate than qRT-PCR as surrogates of HER2 protein determination.

Background. The primary objectives of this study on carcinomas with equivocal HER2 expression were to assess the impact of distinct recommendations with regard to identifying patients eligible for anti-HER2 agents by fluorescence in situ hybridization (FISH) and to elucidate whether multiplex ligation-dependent probe amplification (MLPA) may be of support in assessing HER2 gene status. Methods. A cohort of 957 immunohistochemistry-evaluated HER2-equivocal cases was analyzed by dual-color FISH. The results were assessed according to U.S. Food and Drug Administration (FDA) and European Medicines Agency (EMA) guidelines and American Society of Clinical Oncology (ASCO) and College of American Pathologists (CAP) 2007 and 2013 guidelines for dual- and single-signal in situ hybridization (ISH) assays. A subgroup of 112 cases was subjected to MLPA. Results. HER2 amplification varied from 15% (ASCO/CAP 2007 HER2/CEP17 ratio) to 29.5% (FDA/EMA HER2 copy number). According to the ASCO/CAP 2013 interpretation of the dual-signal HER2 assay, ISH-positive carcinomas accounted for 19.7%. In contrast with the ASCO/CAP 2007 ratio, this approach labeled as positive all 32 cases (3.34%) with a HER2/CEP17 ratio Conclusion. The ASCO/CAP 2013 guidelines seem to improve the identification of HER2-positive carcinomas. Polymerase chain reaction-based methods such as MLPA can be of help, provided that heterogeneous amplification has been ruled out by ISH.

Supplemental digital content is available in the text., Evaluation of the molecular status of 1p and 19q is a major relevant diagnostic, prognostic, and predictive tool for oligodendroglial brain tumors. Fluorescence in situ hybridization (FISH) is the most commonly used technique for determining 1p and 19q allelic losses, but it lacks fully standardized criteria for analysis. This lack of standardization has led to interinstitutional disagreement in the interpretation of results, thereby contributing to a “gray prognostic zone” that includes codeleted patients with an unexpectedly unfavorable outcome. To optimize the prognostic potential of 1p/19q status determination, we first compared the actual criteria used for FISH reading (i.e. different ratio cutoff values and the percentage of neoplastic nuclei carrying this chromosomal deletion) in a retrospective series of 143 pure and mixed oligodendroglial tumors. We then created a “weighted” FISH reading based on the merged ratio and percentage of neoplastic cells carrying the deletion that was further differentially modulated for 1p and 19q, respectively. This weighted codeletion setting significantly strengthened the favorable prognostic power of 1p/19q losses by reducing the number of poor outcomes from 42% to 12.5% for patients with codeleted tumors. Thus, by identifying as codeleted only those cases with more than 50% of cells having a combined loss of 1p (using 0.7 ratio cutoff) and 19q (using 0.8 ratio cutoff) arms, we created a molecular report that bears higher clinical impact and strengthens the prognostic potential of 1p/19q allelic loss.

Evidence supports a role of 17&-estradiol (E2) in carcinogenesis and the large majority of breast carcinomas are dependent on estrogen. The anti-estrogen tamoxifen (TAM) is widely used for both treatment and prevention of breast cancer; however, it is also carcinogenic in human uterus and rat liver, highlighting the profound complexity of its actions. The nature of E2- or TAM-induced chromosomal damage has been explored using relatively high concentrations of these agents, and only some numerical aberrations and chromosomal breaks have been analyzed. This study aimed to determine the effects of low doses of E2and TAM (10&8 mol L&1and 10&6 mol L&1respectively) on karyotypes of MCF7, T47D, BT474, and SKBR3 breast cancer cells by comparing the results of conventional karyotyping and multi-FISH painting with cell proliferation. Estrogen receptor (ER)-positive (+) cells showed an increase in cell proliferation after E2treatment (MCF7, T47D, and BT474) and a decrease after TAM treatment (MCF7 and T47D), whereas in ER& cells (SKBR3), no alterations in cell proliferation were observed, except for a small increase at 96 h. Karyotypes of both ER+ and ER& breast cancer cells increased in complexity after treatments with E2and TAM leading to specific chromosomal abnormalities, some of which were consistent throughout the treatment duration. This genotoxic effect was higher in HER2+ cells. The ER&/HER2+ SKBR3 cells were found to be sensitive to TAM, exhibiting an increase in chromosomal aberrations. Thesein vitroresults provide insights into the potential role of low doses of E2and TAM in inducing chromosomal rearrangements in breast cancer cells.

Summary Gastric cancer shows intratumoral heterogeneity for human epidermal growth factor receptor 2 expression. We evaluated whether the number of tissue blocks analyzed or the antibodies used may influence the immunohistochemical results in gastrectomy specimens. Clinicopathologic data from 148 patients receiving gastric surgery for cancer were collected. One tissue block for each of 88 primary tumors and 60 paired primary tumors and metastases was examined for human epidermal growth factor receptor 2 status by immunohistochemistry using 3 different antibodies (HercepTest, CB11, and 4B5) and by fluorescent in situ hybridization. Two additional tissue blocks of the primary tumor were tested by immunohistochemistry if the results were negative on the first tissue block. The concordance among the 3 antibodies was 94.5% (testing 1 tissue block). Two cases showed a clinically significant discrepancy between primary tumor (score 0) and lymph nodes metastases (score 3+). Additional block analysis increased both the sensitivity (from 63% to 83%) and the accuracy (from 91% to 94%) of immunohistochemistry as compared with fluorescent in situ hybridization. The multiblock approach could potentially identify a greater number of human epidermal growth factor receptor 2–positive gastric cancers, particularly those with higher levels of intratumor heterogeneity. In turn, human epidermal growth factor receptor 2 positivity correlated with a worse prognosis ( P = .011) and was an independent variable in multivariate analysis (hazard ratio, 1.57). In conclusion, testing more than 1 tissue block of cancer from specimens of gastric resection provides a more reliable human epidermal growth factor receptor 2 assessment regardless of the antibody used.

Approximately 8% of breast cancers show increased copy numbers of chromosome 17 centromere (CEP17) by fluorescence in situ hybridization (FISH) (ie average CEP17 >3.0 per nucleus). Currently, this pattern is believed to represent polysomy of chromosome 17. HER2-amplified cancers have been shown to harbour complex patterns of genetic aberrations of chromosome 17, in particular involving its long arm. We hypothesized that aberrant copy numbers of CEP17 in FISH assays may not necessarily represent true chromosome 17 polysomy. Eighteen randomly selected CEP17 polysomic cases and a control group of ten CEP17 disomic cases, as defined by dual-colour FISH, were studied by microarray-based comparative genomic hybridization (aCGH), which was performed on microdissected samples using a 32K tiling-path bacterial artificial chromosome microarray platform. Additional FISH probes were employed for SMS (17p11.2) and RARA (17q21.2) genes, as references for chromosome 17 copy number. Microarray-based comparative genomic hybridization revealed that 11 out of the 18 polysomic cases harboured gains of 17q with involvement of the centromere, one displayed 17q gain sparing the centromeric region, and only one could be defined as polysomic. The remaining five cases displayed amplification of the centromeric region. Among these, one case, showing score 2+ by immunohistochemistry and 8.5 HER2 mean copy number, was classified as not amplified by HER2/CEP17 ratio and as amplified by HER2/SMS ratio. Our results suggest that true chromosome 17 polysomy is likely to be a rare event in breast cancer and that CEP17 copy number greater than 3.0 in FISH analysis is frequently related to gain or amplification of the centromeric region. Larger studies investigating the genetic profiles of CEP17 polysomic cases are warranted.

The TK receptor MET orchestates 9invasive growth9, a genetic program driving the metastatic process. Deregulation of MET signaling pathway occurs via different mechanisms: protein overexpression, gene amplification, mutations or rearrangements. While the role of MET mutations in NSCLC is not yet fully understood, MET amplification drives cell survival and MET-amplified cells are sensitive to MET inhibition. This study aimed to evaluate the occurrence of genetic lesions affecting MET locus on 7q31.1 in primary e metastatic NSCLCs and to decipher a distribution pattern based on disease stage and outcome. A cohort of 69 cases of NSCLC and their matched brain metastases were firstly screened for the expression MET by IHC. Genomic tumor DNA was then sequenced to identify either MET somatic mutations, whereas gene copy number was carried on through FISH analysis on FFPE slides. The results found were then matched with corresponding clinical data. We demonstrate that MET locus was mainly overexpressed in NSCLC metastatic sites. MET somatic mutations were found in 5 of the 54 cases (9%) analysed : in two cases the same mutation was present in both primary and metastatic tissue, whereas in the remaining three mutation affected only brain metastasis. MET amplification was associated to a worst outcome and a poor response to chemotherapy. MET activation was related to tumor radioresistance. (p

Background: In diagnostic pathology, HER2 status is determined in interphase nuclei by fluorescence in situ hybridization (FISH) with probes for the HER2 gene and for the chromosome 17 centromere (CEP17). The latter probe is used as a surrogate for chromosome 17 copies, however chromosome 17 (Chr17) is frequently rearranged. The frequency and type of specific structural Chr17 alterations in breast cancer have been studied by using comparative genomic hybridization and spectral karyotyping, but not fully detailed. Actually, balanced chromosome rearrangements (e.g. translocations or inversions) and low frequency mosaicisms are assessable on metaphases using G-banding karyotype and multicolor FISH (M-FISH) only. Methods: We sought to elucidate the CEP17 and HER2 FISH patterns of interphase nuclei by evaluating Chr17 rearrangements in metaphases of 9 breast cancer cell lines and a primary culture from a triple negative breast carcinoma by using G-banding, FISH and M-FISH. Results: Thirty-nine rearranged chromosomes containing a portion of Chr17 were observed. Chromosomes 8 and 11 were the most frequent partners of Chr17 translocations. The lowest frequency of Chr17 abnormalities was observed in the HER2-negative cell lines, while the highest was observed in the HER2-positive SKBR3 cells. The MDA-MB231 triple negative cell line was the sole to show only non-altered copies of Chr17, while the SKBR3, MDA-MB361 and JIMT-1 HER2-positive cells carried no normal Chr17 copies. True polysomy was observed in MDA-MB231 as the only Chr17 alteration. In BT474 cells polysomy was associated to Chr17 structural alterations. By comparing M-FISH and FISH data, in 8 out of 39 rearranged chromosomes only CEP17 signals were detectable, whereas in 14 rearranged chromosomes HER2 and STARD3 genes were present without CEP17 signals. HER2 and STARD3 always co-localized on the same chromosomes and were always co-amplified, whereas TOP2A also mapped to different derivatives and was co-amplified with HER2 and STARD3 on SKBR3 cells only. Conclusion: The high frequency of complex Chr17 abnormalities suggests that the interpretation of FISH results on interphase nuclei using a dual probe assay to assess gene amplification should be performed 'with caution', given that CEP17 signals are not always indicative of normal unaltered or rearranged copies of Chr17. © 2014 Rondón-Lagos et al.

Background: The MCF7 (ER+/HER2-), T47D (ER+/HER2-), BT474 (ER+/HER2+) and SKBR3 (ER-/HER2+) breast cancer cell lines are widely used in breast cancer research as paradigms of the luminal and HER2 phenotypes. Although they have been subjected to cytogenetic analysis, their chromosomal abnormalities have not been carefully characterized, and their differential cytogenetic profiles have not yet been established. In addition, techniques such as comparative genomic hybridization (CGH), microarray-based CGH and multiplex ligation-dependent probe amplification (MLPA) have described specific regions of gains, losses and amplifications of these cell lines; however, these techniques cannot detect balanced chromosomal rearrangements (e.g., translocations or inversions) or low frequency mosaicism. Results: A range of 19 to 26 metaphases of the MCF7, T47D, BT474 and SKBR3 cell lines was studied using conventional (G-banding) and molecular cytogenetic techniques (multi-color fluorescence in situ hybridization, M-FISH). We detected previously unreported chromosomal changes and determined the content and frequency of chromosomal markers. MCF7 and T47D (ER+/HER2-) cells showed a less complex chromosomal make up, with more numerical than structural alterations, compared to BT474 and SKBR3 (HER2+) cells, which harbored the highest frequency of numerical and structural aberrations. Karyotype heterogeneity and clonality were determined by comparing all metaphases within and between the four cell lines by hierarchical clustering. The latter analysis identified five main clusters. One of these clusters was characterized by numerical chromosomal abnormalities common to all cell lines, and the other four clusters encompassed cell-specific chromosomal abnormalities. T47D and BT474 cells shared the most chromosomal abnormalities, some of which were shared with SKBR3 cells. MCF7 cells showed a chromosomal pattern that was markedly different from those of the other cell lines. Conclusions: Our study provides a comprehensive and specific characterization of complex chromosomal aberrations of MCF7, T47D, BT474 and SKBR3 cell lines.The chromosomal pattern of ER+/HER2- cells is less complex than that of ER+/HER2+ and ER-/HER2+ cells. These chromosomal abnormalities could influence the biologic and pharmacologic response of cells. Finally, although gene expression profiling and aCGH studies have classified these four cell lines as luminal, our results suggest that they are heterogeneous at the cytogenetic level. © 2014Rondón-Lagos et al.; licensee BioMed Central Ltd.

Background and aim We identified a balanced de novo translocation involving chromosomes Xq25 and 8q24 in an eight year-old girl with a non-progressive form of congenital ataxia, cognitive impairment and cerebellar hypoplasia. Methods and Results Breakpoint definition showed that the promoter of the Protein Tyrosine Kinase 2 ( PTK2 , also known as Focal Adhesion Kinase, FAK ) gene on chromosome 8q24.3 is translocated 2 kb upstream of the THO complex subunit 2 ( THOC2 ) gene on chromosome Xq25. PTK2 is a well-known non-receptor tyrosine kinase whereas THOC2 encodes a component of the evolutionarily conserved multiprotein THO complex, involved in mRNA export from nucleus. The translocation generated a sterile fusion transcript under the control of the PTK2 promoter, affecting expression of both PTK2 and THOC2 genes. PTK2 is involved in cell adhesion and, in neurons, plays a role in axonal guidance, and neurite growth and attraction. However, PTK2 haploinsufficiency alone is unlikely to be associated with human disease. Therefore, we studied the role of THOC2 in the CNS using three models: 1) THOC2 ortholog knockout in C.elegans which produced functional defects in specific sensory neurons; 2) Thoc2 knockdown in primary rat hippocampal neurons which increased neurite extension; 3) Thoc2 knockdown in neuronal stem cells (LC1) which increased their in vitro growth rate without modifying apoptosis levels. Conclusion We suggest that THOC2 can play specific roles in neuronal cells and, possibly in combination with PTK2 reduction, may affect normal neural network formation, leading to cognitive impairment and cerebellar congenital hypoplasia.

Primary cultures represent an invaluable tool to set up functional experimental conditions; however, creation of tissue cultures from solid tumors is troublesome and often unproductive. Several features can affect the success rate of primary cultures, including technical issues from pre-analytical procedures employed in surgical theaters and pathology laboratories. We have recently introduced a new method of collection, transfer, and preservation of surgical specimens that requires immediate vacuum sealing of excised specimens at surgical theaters, followed by time-controlled transferring at 4°C to the pathology laboratory. Here we investigate the feasibility and performance of short-term primary cell cultures derived from vacuum packed and cooled (VPAC) preserved tissues. Tissue fragments were sampled from 52 surgical specimens of tumors larger than 2 cm for which surgical and VPAC times (the latter corresponding to cold ischemia time) were recorded. Cell viability was determined by trypan blue dye-exclusion assay and hematoxylin and eosin and immunohistochemical stainings were performed to appreciate morphological and immunophenotypical features of cultured cells. Cell viability showed a range of 84–100% in 44 out of 52 (85%) VPAC preserved tissues. Length of both surgical and VPAC times affected cell viability: the critical surgical time was set around 1 hour and 30 minutes, while cells preserved a good viability when kept for about 24 hours of vacuum at 4°C. Cells were maintained in culture for at least three passages. Immunocytochemistry confirmed the phenotype of distinct populations, that is, expression of cytokeratins in epithelioid cells and of vimentin in spindle cells. Our results suggest that VPAC preserved tissues may represent a reliable source for creation of primary cell cultures and that a careful monitoring of surgical and cold ischemia times fosters a good performance of primary tissue cultures.

Merkel cell carcinoma of the skin is a malignant neuroendocrine tumour, whose prognostic criteria are a matter of dispute. Specifically, no predictor is presently available in stage I–II tumours. We collected clinical and follow-up data from 70 Merkel cell carcinomas of the skin. The same cases were studied for p63 expression by immunohistochemistry, by reverse-transcription PCR (RT-PCR) and TP63 gene status by FISH and for presence of Merkel cell polyomavirus by PCR. Stage emerged as a significant prognostic parameter (P¼0.008). p63 expression, detected in 61% (43/70) of cases by immunohistochemistry, was associated with both decreased overall survival (Po0.0001) and disease-free survival (Po0.0001). Variable expression patterns of the different p63 isoforms were found only in cases immunoreactive for p63. In these latter lesions, at least one of the N-terminal p63 isoforms was detected and TAp63a was the most frequently expressed isoform. TP63 gene amplification was observed by FISH in only one case. Presence of Merkel cell polyomavirus DNA sequences was detected in 86% (60/70) of Merkel cell carcinomas and did not emerge as a significant prognostic parameter. Merkel cell carcinoma cases at low stage (stage I-II) represented over half (40/70 cases, 57%) of cases, and the clinical course was uneventful in 25 of 40 cases while 15 cases died of tumour (10/40 cases) within 34 months or were alive with disease (5/40 cases) within 20 months. Interestingly, a very strict correlation was found between evolution and p63 expression (Po0.0001). The present data indicate that p63 expression is associated with a worse prognosis in patients with Merkel cell carcinoma, and in localised tumours it represents the single independent predictor of clinical evolution.

Approximately 8% of breast cancers show increased copy numbers of chromosome 17 centromere (CEP17) by fluorescence in situ hybridization (FISH) (ie average CEP173.0 per nucleus). Currently, this pattern is believed to represent polysomy of chromosome 17. HER2-amplified cancers have been shown to harbour complex patterns of genetic aberrations of chromosome 17, in particular involving its long arm. We hypothesized that aberrant copy numbers of CEP17 in FISH assays may not necessarily represent true chromosome 17 polysomy. Eighteen randomly selected CEP17 polysomic cases and a control group of ten CEP17 disomic cases, as defined by dual-colour FISH, were studied by microarray-based comparative genomic hybridization (aCGH), which was performed on microdissected samples using a 32K tiling-path bacterial artificial chromosome microarray platform. Additional FISH probes were employed for SMS (17p11.2) and RARA (17q21.2) genes, as references for chromosome 17 copy number. Microarray-based comparative genomic hybridization revealed that 11 out of the 18 polysomic cases harboured gains of 17q with involvement of the centromere, one displayed 17q gain sparing the centromeric region, and only one could be defined as polysomic. The remaining five cases displayed amplification of the centromeric region. Among these, one case, showing score 2+ by immunohistochemistry and 8.5 HER2 mean copy number, was classified as not amplified by HER2/CEP17 ratio and as amplified by HER2/SMS ratio. Our results suggest that true chromosome 17 polysomy is likely to be a rare event in breast cancer and that CEP17 copy number greater than 3.0 in FISH analysis is frequently related to gain or amplification of the centromeric region. Larger studies investigating the genetic profiles of CEP17 polysomic cases are warranted.

In humans, renal resident stem cells were identified within the interstitium, the tubular cells, and the Bowman's capsule. The aim of the present study was to investigate whether multipotent stem cells are present also in the adult human-decapsulated glomeruli and whether they represent a resident population. We found that human glomeruli deprived of the Bowman's capsule contain a population of CD133+CD146+ cells and a population of CD133-CD146+ cells expressing mesenchymal stem cell (MSC) markers and renal stem cell markers CD24 and Pax-2. The CD133+CD146+ cells differed from those previously isolated from Bowman's capsule as they co-expressed endothelial markers, such as CD31 and von Willebrand factor (vWF), were CD24-negative and were not clonogenic, suggesting an endothelial commitment. The glomerular mesenchymal CD133-CD146+ population (Gl-MSC) exhibited self-renewal capability, clonogenicity, and multipotency. In addition to osteogenic, adipogenic, and chondrogenic differentiation, these cells were able to differentiate to endothelial cells and epithelial cells expressing podocytes markers such as nephrin, podocin, and synaptopodin. Moreover, Gl-MSC when cultured in appropriate conditions, acquired mesangial cell markers such as alpha-smooth muscle actin (alpha-SMA) and angiotensin II (AT-II) receptor I. The expression of the embryonic organ-specific PAX-2 gene and protein and of donor sex identity when isolated from glomeruli of a renal allograft suggested these cells to be a tissue resident population. In conclusion, these results indicate the presence of a multipotent mesenchymal cell population resident in human glomeruli that may have a role in the physiological cell turnover and/or in response to glomerular injury.

It has been hypothesized that human clinical neocentromeres and evolutionary novel centromeres (ENC) represent two faces of the same phenomenon. However, there are only two reports of loci harboring both a novel centromere and a clinical neocentromere. We suggest that only the tip of the iceberg has been scratched because most neocentromerization events have a very low chance of being observed. In support of this view, we report here on a neocentromere at 9q33.1 that emerged in a ring chromo- some of about 12 Mb. The ring was produced by a balanced rearrangement that was fortuitously discovered because of its malsegregation in the propositus. Chromatin-immuno- precipitation-on-chip experiments using anti-centromere protein (CENP)-A and anti-CENP-C antibodies strongly indicated that a novel centromeric domain was present in the ring, in a chromosomal domain where an ENC emerged in the ancestor to Old World monkeys.

Williams-Beuren syndrome (WS) is a rare multi-system genomic disorder, caused by 7q11.23 microdeletion with a prevalence of 1/7500-1/20,000 live births. Clinical phenotype includes typical facial dysmorphism (elfin face), mental retardation associated with a peculiar neuropsychological profile and congenital heart defects. We investigated 22 WS patients (mean age of 9.7 years, range 1 day to 39 years) with a multi-specialist follow-up protocol comprehensive of neuropsychological, cardiologic, nephrologic, ophthalmologic, endocrinologic, gastroenterologic, odontostomatologic and orthopaedic evaluations. The mean age at diagnosis was 5.38 years, being 1.02 years when genetic evaluation was requested for congenital heart defects (CHD) and 10.68 years in case of mental retardation and/or abnormal neuropsychological profile without an evident CHD. All patients showed facial dysmorphisms, with supravalvular aortic stenosis (SVAS) as the most common cardiovascular anomaly (12/22), followed by peripheral pulmonary stenosis (9/22); interestingly, in one patient we detected a total anomalous pulmonary venous return (TAPVR), confirming the possible association of this rare CHD with WS. Hypertension was detected by 24-h ambulatory blood pressure monitoring in 7/22 cases. A cognitive assessment was performed in 13 patients older than 6 years, showing various degrees of mental retardation in 12 and a normal intelligence quotient (IQ) in a single patient; evaluation of developmental milestones revealed various grades of developmental delay in all the patients younger than 6 years. Chiari malformation type 1 was found in 3 patients. Our study underlines a remarkable diagnostic delay in patients who present to genetic evaluation because of mental retardation and/or peculiar neuropsychological profile lacking an evident cardiopathy and confirms the multi-systemic nature of WS leading to a high clinical presentation's variability and complex follow-up strategies.

PURPOSE: We evaluated the experiences of 19 Italian laboratories concerning 241 small supernumerary marker chromosomes (sSMCs) with the aim of answering questions arising from their origin from any chromosome, their variable size and genetic content, and their impact on the carrier's phenotype. METHODS: Conventional protocols were used to set up the cultures and chromosome preparations. Both commercial and homemade probes were used for the fluorescent in situ hybridization analyses. RESULTS: A total of 113 of the 241 sSMCs were detected antenatally, and 128 were detected postnatally. There were 52 inherited and 172 de novo cases. Abnormal phenotype was present in 137 cases (57%), 38 of which were antenatally diagnosed. A mosaic condition was observed in 87 cases (36%). In terms of morphology, monocentric and dicentric bisatellited marker chromosomes were the most common, followed by monocentric rings and short-arm isochromosomes. The chromosomes generating the sSMCs were acrocentric in 132 cases (69%) and non-acrocentric chromosomes in 60 cases (31%); a neocentromere was hypothesized in three cases involving chromosomes 6, 8, and 15. CONCLUSION: The presented and published data still do not allow any definite conclusions to be drawn concerning karyotype-phenotype correlations. Only concerted efforts to characterize molecularly the sSMCs associated or not with a clinical phenotype can yield results suitable for addressing karyotype-phenotype correlations in support of genetic counseling.

Background: Immunohistochemistry (IHC) and fluorescence-in-situ hybridization (FISH) are the standard methods to assess human epidermal growth factor receptor 2 (HER-2) status in breast cancer (BC) patients. Real-time quantitative polymerase-chain-reaction (Q-PCR) and quantitative reverse transcriptase PCR (qRT-PCR) allow quantitative determination of gene copy number and gene expression on, respectively, DNA and RNA. These molecular methods are available to assess HER-2 amplification/overexpression but their use remains controversial. Here we performed a parallel comparison of these four methods to define their concordance rates and evaluate their relative role in HER-2 status determination. Patients and Methods: HER-2 status was determined by IHC, FISH, Q-PCR and qRT-PCR in a retrospectively assessed cohort of 130 BC patients. The studied set was enriched in cases scoring as 3+ by standard IHC analysis. Tests were performed blindly in parallel. Western blotting was performed on a subset of equivocal cases. Kappa statistics and ROC curves were used as appropriate, and concordance analyses were interpreted according to the ASCO/CAP guidelines. Results: Of the 130 enrolled patients, 47 (36%) were classified as positive and 27 (21%) as equivocal by IHC. With FISH, 50 patients (38%) were HER-2 amplified, while 80 (62%) were not. The overall agreement between FISH and Q-PCR was 98.5% (95% CI, 94.6% to 99.6%) with a k value of 0.97 (95% CI, 0.92 to 1). Assuming FISH as the standard reference, Q-PCR showed a sensitivity of 98% (95% CI, 89.5% to 99.6%) and a specificity of 98.8% (95% CI, 93.3% to 99.8%), with a global accuracy of 98%. The overall agreement between FISH and qRT-PCR was 96.9% (95% CI, 92.3% to 98.8%) with a k value of 0.94 (95% CI, 0.87 to 1). For both comparisons, the observed concordance values were greater than the 95% threshold required by the ASCO/CAP guidelines to validate novel approaches for HER-2 testing. 3% of samples showed HER-2 overexpression only by qRT-PCR analysis, in all cases belonging to the equivocal range as defined by either IHC or FISH. In these patients, WB confirmed higher HER-2 protein levels compared to healthy diploid controls. Conclusions: The high concordance between FISH and both Q-PCR and qRT-PCR supports the use of molecular tests as an alternative to current standard methods. Present results also suggest that qRT-PCR may be able to unequivocally classify patients belonging to the IHC/FISH equivocal range. Non-amplified HER-2 overexpressing BCs may account for the rare trastuzumab-responders observed in phase III trials, where trastuzumab response was assessed in HER-2-amplified vs. non-amplified cases. Citation Format: Gabriele Zoppoli, Anna Garuti, Ilaria Rocco, Claudia Palermo, Gabriella Cirmena, Enrico Carminati, Daniele Friedman, Ludovica Verdun di Cantogno, Anna Sapino, Franco Patrone, Alberto Ballestrero. Agreement of immunohistochemistry, fluorescence in situ hybridization, real-time quantitative polymerase-chain reaction, and quantitative reverse transcriptase PCR for Her-2/Neu status assessment in breast cancer patients: a single center, retrospective m [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 49. doi:10.1158/1538-7445.AM2013-49

Exponentially growing L929 cells were continuously exposed to 1 or 10 microM etoposide (VP-16). The effects of such treatment on cell growth, cycle distribution, morphology, and selected biochemical events were examined. DNA synthesis rates were markedly decreased and the protein/DNA ratio increased (unbalanced growth). Growth was blocked, with most cells being cycle arrested by 24 h in (late S-)G2-M. An asynchronous process of cell death then developed. Cells initially shrank into eosinophilic, trypan blue-excluding bodies, which were then released into the medium, and eventually became permeable to trypan blue. Transmission electron microscopy confirmed that dying cells acquired an apoptotic morphotype, with compaction and margination of chromatin, loss of microvilli, and shrinkage of cytoplasm and nucleus. Tissue transglutaminase activity and intensity of immunostaining rapidly increased in treated cultures. Internucleosomal DNA fragmentation could not be detected by agarose gel electrophoresis, yet flow cytometry revealed that the apoptotic bodies had a very low DNA fluorescence (or = 10% of the 2n value). In agreement with the microscopic findings, this suggested that extensive DNA degradation had occurred in dead cells. While rates of cell loss from the monolayer amounted to 21 and 57% day(-1) (1 and 10 microM VP-16, respectively), apoptotic indexes largely underestimated the extent of the process. These indexes only measured the accumulation of apoptotic bodies, i.e., the balance between their generation and disposal. The latter occurred by mechanisms similar to those that operate in tissues: "secondary necrosis" or phagocytosis by viable homotypic cells in the monolayer ("homophagy").

Primary olfactory neurons located in the olfactory neuroepithelium project to the ipsilateral olfactory bulb and undergo a continuous process of neurogenesis and differentiation. We describe, in the adult rat, the kinetics of proliferation, differentiation and survival of primary olfactory neurons either in the presence or absence of their target, the olfactory bulb. The experimental design included unilateral bulbectomy, coupled with a single bromodeoxyuridine pulse 35 days after surgery. The rate of proliferation and survival of olfactory neurons was then examined by immunohistochemistry for bromodeoxyuridine, and the differentiation status by in situ hybridization for calmodulin messenger RNA in immature and mature olfactory neurons and immunohistochemistry for the dipeptide carnosine in mature olfactory neurons. We show that primary olfactory neurons can synthesize carnosine in the absence of the olfactory bulb. However, the number of carnosine-immunopositive neurons in the absence of their target is dramatically reduced to less than one-fourth, whereas the number of olfactory neurons expressing calmodulin messenger RNA is only slightly reduced. The numeric reduction of carnosine-positive neurons in the target-deprived neuroepithelium is correlated with a dramatic reduction in the survival rate of olfactory neurons, since newly generated olfactory neurons are completely lost 35 days after the bromodeoxyuridine pulse. In contrast, in the normal olfactory neuroepithelium almost one-third of newly generated olfactory neurons survive 35 days after the bromodeoxyuridine pulse. On the whole, these data indicate that most of the primary olfactory neurons have a short lifespan but that once they have connected with the olfactory bulb they may persist longer, and suggest that throughout adulthood olfactory neurons are overproduced, differentiate independently from their target, and then undergo a process of target-induced neuronal selection.

Olfaction plays a dominant role in modulating behaviour in most vertebrate species and the olfactory bulb is considered a model system for characterizing principles of neural computation. Nevertheless, although the physiology and neurochemistry of the olfactory circuits have been widely studied, the neurotransmitter released by olfactory receptor neurones remains unknown. We now describe the ultrastructural localization of the dipeptide carnosine and the excitatory amino acid glutamate in the glomerular layer of the mouse olfactory bulb. We demonstrate that both carnosine-like and glutamate-like immunoreactivities are selectively co-localized in the olfactory neurone boutons. These observations, taken with the recent findings of glutamate-receptor subunit expression in rodent olfactory bulb, argue compellingly for a role of glutamate in olfactory neurotransmission and suggest a modulatory effect of carnosine.