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Rosa Noguera

Publications and source records attributed to Rosa Noguera.

13 recordsLinked to original sources
PubMed2007

Evaluation of genetic stability of the SYT gene rearrangement by break-apart FISH in primary and xenotransplanted synovial sarcomas.

Synovial sarcomas (SS) are infrequent and morphologically heterogeneous soft tissue sarcomas. The t(X;18)(p11.2;q11.2), which results in fusion of the SYT gene at 18q11 with the SSX1, SSX2, or (rarely) SSX4 gene is a primary genetic event in 90% of SS. To determine whether the t(X;18) present in the original tumor is maintained in its passages, a dual-color break-apart FISH assay for SYT gene disruption was performed in two tissue microarrays (TMA) comprising eight molecularly confirmed primary SSs and their xenografts, which were followed for several generations. A simplified scoring system was applied to the FISH results of the primary and xenotransplanted SS to classify the FISH data into distinct groups. SYT disruption was identified in all eight primary SS and in all their passages without any significant differences among them, despite wide variations in xenotransplantation time between the primary tumors and their xenografts. The TMA-based FISH assay demonstrated genetic stability related to SYT gene rearrangement in primary and xenografted SS.

Animals↗
PubMed2006

Comparative effects of estradiol, raloxifene, and genistein on the uterus of ovariectomized mice.

To explore the uterine effects of administration of compounds that exert their bone-sparing functions through estrogen receptors, we administered 17beta-E2, raloxifene, or genistein to ovariectomized mice and analyzed the uterus weight and histology 4 weeks after beginning the treatments. Results indicated that raloxifene and genistein have partial agonistic properties on the uterus in estrogen-depleted mice, and that genistein induced apoptosis and several atypias in the glandular epithelium of endometrium, as demonstrated in hematoxylin-eosin-stained histological sections.

Animals↗
PubMed2006

Prognostic value of the International Neuroblastoma Pathology Classification in Neuroblastoma (Schwannian stroma-poor) and comparison with other prognostic factors: a study of 182 cases from the Spanish Neuroblastoma Registry.

In addition to clinical and biological factors, further valuable prognostic information in neuroblastoma (Schwannian stroma-poor) (NB) patients is provided by the histopathologic analysis and the application of the International Neuroblastoma Pathology Classification (INPC) system. The objective of this study was to assess the prognostic impact of the INPC classification in a series of NB (Schwannian stroma-poor) and its relation with other prognostic factors. One hundred eighty-two cases of NB were collected from the files of the Spanish Neuroblastoma Registry. Slides were reviewed, and NB cases were grouped into favorable and unfavorable categories according to INPC criteria, taking into account morphological features (mitosis-karyorrhexis index, histological subtype) and patient's age at diagnosis. Other pathological [presence of calcifications, tissular components, and number of mitotic cells per 10 high-power field (HPF)], immunohistochemical (P-glycoprotein and Ki-67 protein expression) and genetic (MYCN amplification and chromosome 1p deletion) features were also studied. Statistical analyses of overall survival with Kaplan-Meier curves and a multivariate study using Cox regression were performed (40.3% of NBs were considered favorable and 59.7% unfavorable). Unfavorable NB showed a mean survival time of 57 months compared with 89 months in favorable cases. Advanced stage, more than ten mitoses per 10 HPF, Ki-67 expression in more than 30% of tumor cells, MYCN oncogene amplification and chromosome 1p deletion were observed more frequently in unfavorable NB. The Cox regression analysis demonstrated that clinical stage (International Neuroblastoma Staging System stage 4) and histological subtype (undifferentiated NB) were the most important factors that influence the overall survival (p<0.001). INPC classification results are major prognostic indicators in NB and should be considered in the therapeutic stratification of NB patients.

Child↗
PubMed2006

HER2 amplification in recurrent breast cancer following breast-conserving therapy correlates with distant metastasis and poor survival.

The authors analyzed the HER2 status in early-stage nonrecurrent and recurrent breast cancer groups following breast-conserving treatment. Retrospective analyses of a group of 36 invasive early breast cancer (IBC) patients who developed a local recurrence as a first event and of a random control group of 69 IBC patients were made. HER2 status was assessed by the HercepTest and fluorescence in situ hybridization. The Kaplan-Meier proportional log-rank test was used to study the impact of the biological factors on the metastasis-free interval (MFI) and the overall survival (OS). The Cox proportional hazards model, using stepwise selection was performed to identify the independent predictors of poor outcome. The median time of follow-up was 156 months (range: 22-230) for the nonrecurrent group of patients and 119 months (range: 36-228) for the recurrent group. No significant differences between either group were observed in terms of either patient or tumor characteristics, or of HER2 expression. However, a higher proportion of HER2 amplified cases were found in the recurrent group, in contrast to a higher proportion of hormonal receptor positive cases in the nonrecurrent group. After univariate and multivariate analyses, HER2 amplification was found to be an independent predictive factor for distant metastasis (HR = 10.75; p = 0.00008) and for survival (HR = 4.22; p = 0.004). In conclusion, HER2 amplification constitutes an independent poor prognostic factor for the MFI and OS in patients with recurrent breast cancer. The clinical implications are discussed.

Adult↗
PubMed2006

Recruitment of HIF-1alpha and HIF-2alpha to common target genes is differentially regulated in neuroblastoma: HIF-2alpha promotes an aggressive phenotype.

In neuroblastoma specimens, HIF-2alpha but not HIF-1alpha is strongly expressed in well-vascularized areas. In vitro, HIF-2alpha protein was stabilized at 5% O2 (resembling end capillary oxygen conditions) and, in contrast to the low HIF-1alpha activity at this oxygen level, actively transcribed genes like VEGF. Under hypoxia (1% O2), HIF-1alpha was transiently stabilized and primarily mediated acute responses, whereas HIF-2alpha protein gradually accumulated and governed prolonged hypoxic gene activation. Knockdown of HIF-2alpha reduced growth of neuroblastoma tumors in athymic mice. Furthermore, high HIF-2alpha protein levels were correlated with advanced clinical stage and high VEGF expression and predicted poor prognosis in a clinical neuroblastoma material. Our results demonstrate the relevance of HIF-2alpha in neuroblastoma progression and have general tumor biological implications.

Animals↗
PubMed2006

GIST: particular aspects related to cell cultures, xenografts, and cytogenetics.

In less than half a decade, gastrointestinal stromal tumors (GIST) have emerged from historical anonymity to become a model of kinase-targeted therapies. Approximately 80% to 85% of GISTs harbor activating mutations of the KIT or PDGFRA tyrosine kinase genes, and such mutations have predictive and prognostic value. In this regard, the in vitro and in vivo models have provided valuable tools for understanding the molecular pathology of this interesting neoplasm. This review charts particular aspects in the field of cell cultures and tumor xenografts in nude mice in GIST and their implication in the establishment of appropriate models for discovering and testing therapy. The cytogenetic features of these tumors are also discussed. Classic karyotyping, loss of heterozygosity, fluorescent in situ hybridization, comparative genomic hybridization (CGH), and CGH-array analyses have shown that chromosomal numerical abnormalities and loss of genetic material at chromosomes 1p, 9p, 14q, and 22q are significantly associated with GIST malignancy and response to treatment. Furthermore, these regions constitute "hot" areas for finding candidate genes involved in the pathogenesis of GISTs. A deeper knowledge of these genetic aspects of GIST will provide a better understanding of this neoplasm that could translate into clinical practice.

Animals↗
PubMed2006

p16INK4A (CDKN2A) gene deletion is a frequent genetic event in synovial sarcomas.

We assessed the frequency of genomic deletion of p16INK4A (CDKN2A) in synovial sarcomas (SSs) and its possible association with immunoexpression of p16 and cyclin D1 and the Ki-67 proliferation index using dual-color fluorescence in situ hybridization (FISH) on tissue microarray sections of 41 histologically and molecularly confirmed SSs. A heterozygous p16INK4A gene deletion was identified in 28 (74%) of 38 cases, with 25 (89%) of them showing abnormal p16 protein expression (20 negative and 5 heterogeneous). Of 25 cases, 19 (76%) exhibiting increased cyclin D1expression also demonstrated heterozygous p16INK4A deletion. No significant association was observed between p16INK4A deletion and Ki-67 proliferation index, tumor grade, or histologic subtype. Our results demonstrate that p16INK4A (CDKN2A) gene deletion is a frequent genetic event in SS.

Biomarkers, Tumor↗
PubMed2005

[Neuroblastoma].

Explore the source record for details and available documents.

Forecasting↗
PubMed2005

Mutational analysis of the c-KIT AND PDGFRalpha in a series of molecularly well-characterized synovial sarcomas.

The c-KIT and the platelet-derived growth factor receptor alpha (PDGFRalpha) have been shown to be important for tumor growth and progression in several soft-tissue sarcomas, including synovial sarcomas (SSs). It has been suggested that these c-KIT-positive cases might benefit from a tyrosine kinase inhibitor therapy. In this study, we analyze a series of SSs to investigate the presence of c-KIT and PDGFRalpha mutations with the aim of selecting those for a more adequate and appropriate therapy. We analyzed fresh-frozen tissues from 12 SSs (8 primary tumors and 4 nude mice xenotransplants from primary tumors). RNA was extracted to identify the presence of the SYT-SSX gene fusion to confirm the SS diagnosis. Mutational analysis of exons 9, 11, 13, and 17 of c-KIT and exons 12 and 18 of PDGFRalpha was performed by direct sequencing. Immunohistochemical analysis of c-KIT, PDGFRalpha, and p-PDGFRalpha was also performed. All analyzed cases showed the presence of SYT-SSX gene fusion transcripts confirming the diagnosis of SS, 10 carried the SYT-SSX1 fusion, and 2 the SYT-SSX2. Immunohistochemical analysis showed expression of c-KIT in 3 cases in which no molecular alterations were detected. For the PDGFRalpha, we observed an in-frame deletion of codons 554 and 555 in a case which also showed a strong immunopositivity for the phosphorylated form of PDGFRalpha. PDGFRalpha expression was observed in 8 cases. We suggest that a more exhaustive mutational analysis of the c-KIT and PDGFRalpha genes should be performed to ascertain which cases would really benefit from a tyrosine kinase inhibitor therapy in SS.

Adolescent↗
PubMed2003

MYCN gain and MYCN amplification in a stage 4S neuroblastoma.

Stage 4S neuroblastoma is a disease associated with spontaneous regression and good survival. We present a patient whose evolution has shown the variety and complexity of this disease in infants. Biologic factors, such as ploidy, MYCN copy number, loss of 1p36, and other chromosomal gains and losses were determined. A complex pattern of genetic abnormalities, such as near-diploidy, MYCN gain (2-4 copies per haploid genome) and imbalance/deletion of 1p36 was seen in the diagnostic sample. An extensive disseminated disease after a latent period of 26 months was associated with a special genetic evolution, such a tetraploidy, MYCN amplification (2:100-500 copies), 1p36 deletion, and gain of 17q. Our results provide evidence that either the primary tumor was heterogeneous in terms of gene amplification or that amplification was acquired later on as a transition from MYCN gain. We suggest that near-di-/tetraploid 4S tumors with MYCN gain and/or deletion 1p could be progressing 4S tumors.

Adrenal Gland Neoplasms↗
PubMedDate not supplied

Histological tumor grade correlates with HER2/c-erB-2 status in invasive breast cancer: a comparative analysis between immunohistochemical (CB11 clone and Herceptest), FISH and differential PCR procedures.

There is a growing clinical demand for analysis of the HER2/c-erbB-2 (HER2) status of breast cancer specimens because it provides valuable prognostic, predictive and therapeutic information. In this sense, a variety of methods is available for detection of HER2 status, although to date a reliable and sensitive test does not exist. In order to choose the most suitable procedure to assess HER2 status, we analyzed 102 invasive breast cancers for HER2 overexpression by means of immunohistochemistry (IHC), with the CB11 Mo-Ab and the Hercep Test kit, and for HER2 gene amplification by fluorescence in situ hyubridization (FISH) and differential PCR (dPCR). HER2 overexpression, determined by CB11 (group C) and HercepTest (2+ and 3+), was observed in 19 samples (18.6%) whereas genetic amplification was detected in 31 (30.4%) and 14 (13.7%) cases by FISH and dPCR, respectively. The majority of overexpressed/amplified specimens corresponded to high grade tumors. We found concordances of 78-80% and 93-95% between IHC vs FISH and IHC vs dPCR, respectively. Considering FISH procedure as a gold standard, we found a sensitivity and specificity of 48.4% and 94.3% for CB11 antibody, of 45.2% and 92.9% for HercepTest, and of 45.2% and for 100% for the dPCR. Thus, considering the sensitivity, specificity and the high grade of concordance between IHC and dPCR, we suggest the use of IHC for assessing HER2 status. However, due that sensitivity of IHC test is lower than FISH, we also suggest to carry out FISH on those cass in which IHC results are not definitive for its clinical evaluation.

Adenocarcinoma↗