46 research outputs found

    Microsatellite instability, immunohistochemistry and germline mismatch repair gene mutations for the diagnosis of Muir-Torre syndrome in immunosuppressed patients

    Get PDF
    Although rare sebaceous tumors and keratoacanthomas are clinical criteria for Muir-Torre syndrome (MTS), they can also be found in the context of immunosuppression. We present here two patients who underwent organ transplantation in which immunosuppression unmasked MTS through the early appearance of the cutaneous sebaceous neoplasms. In all of their sebaceous tumors we detected microsatellite instability (MSI) e loss of mutS protein homolog 2 (MSH2) and 6 (MSH6) expression at immunohistochemistry (IHC). Although in the absence of visceral MTS phenotype, we performed the sequencing analysis for mismatch repair genes (MMR) identifying two novel MSH2 and MSH6 germline mutations. The combination of MSI and IHC status can therefore be considered useful for the recognition of MTS, even in case of incomplete MTS phenotype and/or in immunosuppressed patients. It would allow a costeffective approach to identify individuals who should undergo MMR genes direct sequencing

    Identification of the zinc finger 216 (ZNF216) in human carcinoma cells. A potential regulator of EGFR activity

    Get PDF
    Epidermal Growth Factor Receptor (EGFR), a member of the ErbB family of receptor tyrosine kinase (RTK) proteins, is aberrantly expressed or deregulated in tumors and plays pivotal roles in cancer onset and metastatic progression. ZNF216 gene has been identified as one of Immediate Early Genes (IEGs) induced by RTKs. Overexpression of ZNF216 protein sensitizes 293 cell line to TNF-α induced apoptosis. However, ZNF216 overexpression has been reported in medulloblastomas and metastatic nasopharyngeal carcinomas. Thus, the role of this protein is still not clearly understood. In this study, the inverse correlation between EGFR and ZNF216 expression was confirmed in various human cancer cell lines differently expressing EGFR. EGF treatment of NIH3T3 cells overexpressing both EGFR and ZNF216 (NIH3T3-EGFR/ZNF216), induced a long lasting activation of EGFR in the cytosolic fraction and an accumulation of phosphorylated EGFR (pEGFR) more in the nuclear than in the cytosolic fraction compared to NIH3T3-EGFR cells. Moreover, EGF was able to stimulate an increased expression of ZNF216 in the cytosolic compartment and its nuclear translocation in a time-dependent manner in NIH3T3-EGFR/ZNF216. A similar trend was observed in A431 cells endogenously expressing the EGFR and transfected with Znf216. The increased levels of pEGFR and ZNF216 in the nuclear fraction of NIH3T3-EGFR/ZNF216 cells were paralleled by increased levels of phospho-MAPK and phospho-Akt. Surprisingly, EGF treatment of NIH3T3-EGFR/ZNF216 cells induced a significant increase of apoptosis thus indicating that ZNF216 could sensitize cells to EGF-induced apoptosis and suggesting that it may be involved in the regulation and effects of EGFR signaling

    BRAFp.V600E, p.V600K, and p.V600R Mutations in Malignant Melanoma: Do They Also Differ in Immunohistochemical Assessment and Clinical Features?

    Get PDF
    Although the detection of BRAF p.V600E mutation by immunohistochemistry was clearly described in melanoma, discordant evidences were reported for the detection of p.V600K and p.V600R mutations. The aim of the study was to evaluate the efficacy of BRAFp.V600E, p.V600K, and p.V600R detection by immunohistochemistry in melanoma

    Mutazioni somatiche di BRAF in pazienti affetti da melanoma maligno metastatico ed efficacia clinica degli approcci terapeutici a bersaglio molecolare con inibitori di BRAF

    Get PDF
    L’introduzione di terapie a bersaglio molecolare ha rivoluzionato la prognosi dei pazienti affetti da melanoma in stadio avanzato. Attualmente è possibile determinare lo status molecolare del melanoma analizzando geni quali C-KIT, BRAF ed N-RAS per la scelta di strategie terapeutiche mirate. Mutazioni di BRAF si riscontrano in circa il 50% dei melanomi: tra queste la V600E e la V600K sono maggiormente frequenti e ben studiate nei pregressi protocolli di sperimentazione fase II/III con inibitori di BRAF. Questi ultimi (Dabrafenib e Vemurafenib) hanno dimostrato chiara efficacia nell’indurre risposte obiettive nel melanoma avanzato. Con il presente lavoro presentiamo le preliminari valutazioni delle correlazioni tra tipologie di mutazioni somatiche del gene BRAF riscontrate in una coorte di melanomi in stadio IV e le risposte cliniche a tale inibitori selettivi. A partire dal giugno 2011, 19 pazienti (10 M; 9F; età media 55 anni) affetti da melanoma stage IV BRAF+ sono stati arruolati in protocolli terapeutici con Dabrafenib (150 mg 2 volte/die) o Vemurafenib (960 mg 2volte/die) presso l’Università di Modena. Il restaging strumentale della malattia veniva eseguito a 8 settimane dall’inizio della terapia. Sono state riscontrate mutazione hot spot V600E (c.1799T>A) in 18 pazienti, in due differenti pazienti sono state individuate le rare mutazioni V600M (c.1798G>A) e V600R (c.1790T>G). In un melanoma è stata evidenziata una doppia mutazione (V600E; V600M) ed il relativo paziente, trattato con Dabrafenib, ha presentato una rapida regressione delle importati lesioni metastatiche. In due casi la ricerca mutazionale in BRAF, risultata inizialmente negativa, è stata poi riscontrata in una successiva analisi. I dati clinici preliminari evidenziano una risposta obiettiva già nelle primissime settimane di terapia, buona tolleranza con scarsi effetti collaterali sia nei pazienti con mutazioni V600E che in quelli con le rare mutazioni V600 M e V600R. Il periodo di sopravvivenza medio libero da progressione dei 15 pazienti con follow-up di almeno 8 settimane è stato di 7 mesi. In 9 pazienti persiste la risposta terapeutica ad oggi. La doppia mutazione di BRAF potrebbe costituire un fattore prognostico positivo per la risposta agli inibitori di BRAF. Nei casi negativi alla ricerca mutazionale, dovrebbe essere routinariamente impiegate indagini più approfondite atte ad evidenziare non solo la presenza della comune V600E ma anche delle varianti meno comuni degli esoni 11 e 15

    Long-term adaptation of Daphnia to toxic environment in Lake Orta: the effects of short-term exposure to copper and acidification

    Get PDF
    Because of its 80-year history of heavy pollution and re-colonization, Lake Orta provides a good opportunity for investigating the response of zooplankton organisms to heavy metals and acidification as well as the mechanisms involved. After the recent establishment of Daphnia galeata Sars, and the detection of an extremely low clonal diversity of Lake Orta population, we carried out a study to investigate the lethal tolerance to ionic copper, as well as to acidity, and the impact of newborn Daphnia exposure to sublethal concentrations of copper for their later development and reproduction. We conducted acute toxicity tests to estimate the EC50 for ionic copper and tolerance to low pH, as well as life table experiments. Tolerance to ionic copper was high, three times that reported in literature. An increased mortality soon after exposure to low pH confirmed a high sensitivity to acidity and explained the success of the species in Lake Orta only after pH recovery. An analysis of reproductive and demographic parameters revealed that D. galeata Sars was stressed at concentrations of ionic copper only twice higher than those presently recorded in the lake (i.e., ca 3 μg L-1). An increased cumulative number of eggs produced by each female were in fact counterbalanced by an increasing abortion rate, which resulted in an unaltered or lower intrinsic rate of population increase. Our results are likely due to the strong selective pressure, more than physiological processes (acclimation), in a polluted area in which only specific adapted clones are able to grow, confirming the results previously obtained on Lake Orta's D. obtusa Kurz population. The reproductive response and the relatively low within treatment variability suggest that clone specificity, rather than physiological acclimation, was the driving force. The low variability confirmed results previously obtained from life tables experiments on Lake Orta's D. obtusa clone. Overall, our results suggest that, despite the chemical recovery, Lake Orta may be regarded as highly vulnerable to biodiversity loss

    An ecotoxicological approach to assess the environmental quality of freshwater basins: a possible implementation of the EU Water Framework Directive

    No full text
    Within the context of the Water Framework Directive, the need to identify new monitoring tools in support of the traditional chemical monitoring process is emerging. Chemical characterization by itself does not provide specific biological information about potential hazards to organisms, in particular when facing cocktails of contaminants. Therefore, ecotoxicity tests can represent a useful tool supporting the chemical information. In the present work, the value of ecotoxicity tests as an effect-based tool for monitoring freshwater and sediment quality of the south-western basin of Lake Como (Northern Italy) was evaluated, assessing the potential risk of pollutants. Results obtained from D. magna toxicity tests showed a temporal variation of toxic response in relation to the variability of organic micropollutant load characteristics of urban rivers. Sediment ecotoxicity test data showed the spatial variability of the sediments\u2019 contamination within the lake, confirmed by chemical analysis of two classes of pollutants (dichlorodiphenyltrichloroethane (DDT) and polychlorobiphenyls (PCB)). The observed effects on organisms in laboratory tests caused by a mixture of almost unknown chemicals underline the importance of integrating effect-based tools into monitoring efforts
    corecore