230 resultados para HER2
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We previously demonstrated the synergistic therapeutic effect of the cetuximab (anti-epidermal growth factor receptor [EGFR] monoclonal antibody, mAb)-trastuzumab (anti-HER2 mAb) combination (2mAbs therapy) in HER2(low) human pancreatic carcinoma xenografts. Here, we compared the 2mAbs therapy, the erlotinib (EGFR tyrosine kinase inhibitor [TKI])-trastuzumab combination and lapatinib alone (dual HER2/EGFR TKI) and explored their possible mechanisms of action. The effects on tumor growth and animal survival of the three therapies were assessed in nude mice xenografted with the human pancreatic carcinoma cell lines Capan-1 and BxPC-3. After therapy, EGFR and HER2 expression and AKT phosphorylation in tumor cells were analyzed by Western blot analysis. EGFR/HER2 heterodimerization was quantified in BxPC-3 cells by time-resolved FRET. In K-ras-mutated Capan-1 xenografts, the 2mAbs therapy gave significantly higher inhibition of tumor growth than the erlotinib/trastuzumab combination, whereas in BxPC-3 (wild-type K-ras) xenografts, the erlotinib/trastuzumab combination showed similar growth inhibition but fewer tumor-free mice. Lapatinib showed no antitumor effect in both types of xenografts. The efficacy of the 2mAbs therapy was partly Fc-independent because F(ab')(2) fragments of the two mAbs significantly inhibited BxPC-3 growth, although with a time-limited therapeutic effect. The 2mAbs therapy was associated with a reduction of EGFR and HER2 expression and AKT phosphorylation. BxPC-3 cells preincubated with the two mAbs showed 50% less EGFR/HER2 heterodimers than controls. In pancreatic carcinoma xenografts, the 2mAbs therapy is more effective than treatments involving dual EGFR/HER2 TKIs. The mechanism of action may involve decreased AKT phosphorylation and/or disruption of EGFR/HER2 heterodimerization.
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BACKGROUND: Gastro-oesophageal adenocarcinomas rarely metastasize to the central nervous system (CNS). The role of the human epidermal growth factor receptor 2 (HER2) in patients with these cancers and CNS involvement is presently unknown. PATIENTS AND METHODS: A multicentre registry was established to collect data from patients with gastro-oesophageal adenocarcinomas and CNS involvement both retrospectively and prospectively. Inclusion in the study required a predefined clinical data set, a central neuro-radiological or histopathological confirmation of metastatic CNS involvement and central assessment of HER2 by immunohistochemistry (IHC) and in situ hybridisation (ISH). In addition, expression of E-cadherin and DNA mismatch repair (MMR) proteins were assessed by IHC. RESULTS: One hundred patients fulfilled the inclusion criteria. The population's median age was 59 years (interquartile range: 54-68), of which 85 (85%) were male. Twenty-five patients were of Asian and 75 of Caucasian origin. HER2 status was positive in 36% (95% CI: 26.6-46.2) of cases. Median time from initial diagnosis to the development of brain metastases (BMets) or leptomeningeal carcinomatosis (LC) was 9.9 months (95% CI: 8.5-15.0). Median overall survival from diagnosis was 16.9 months (95% CI: 14.0-20.7) and was not related to the HER2 status. E-cadherin loss was observed in 9% of cases and loss of expression in at least one DNA MMR proteins in 6%. CONCLUSIONS: The proportion of a positive HER2 status in patients with gastro-oesophageal adenocarcinoma and CNS involvement was higher than expected. The impact of anti-HER2 therapies should be studied prospectively.
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Chromogenic immunohistochemistry (IHC) is omnipresent in cancer diagnosis, but has also been criticized for its technical limit in quantifying the level of protein expression on tissue sections, thus potentially masking clinically relevant data. Shifting from qualitative to quantitative, immunofluorescence (IF) has recently gained attention, yet the question of how precisely IF can quantify antigen expression remains unanswered, regarding in particular its technical limitations and applicability to multiple markers. Here we introduce microfluidic precision IF, which accurately quantifies the target expression level in a continuous scale based on microfluidic IF staining of standard tissue sections and low-complexity automated image analysis. We show that the level of HER2 protein expression, as continuously quantified using microfluidic precision IF in 25 breast cancer cases, including several cases with equivocal IHC result, can predict the number of HER2 gene copies as assessed by fluorescence in situ hybridization (FISH). Finally, we demonstrate that the working principle of this technology is not restricted to HER2 but can be extended to other biomarkers. We anticipate that our method has the potential of providing automated, fast and high-quality quantitative in situ biomarker data using low-cost immunofluorescence assays, as increasingly required in the era of individually tailored cancer therapy.
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PURPOSE: To examine the expression of AKT and PTEN in a series of HER2-positive primary invasive breast tumors using immunohistochemistry, and to associate these expression profiles with classic pathologic features such as tumor grade, hormone receptor expression, lymphatic vascular invasion, and proliferation.METHODS: A total of 104 HER2-positive breast carcinoma specimens were prepared in tissue microarrays blocks for immunohistochemical detection of PTEN and phosphorylated AKT (pAKT). Original histologic sections were reviewed to assess pathological features, including HER2 status and Ki-67 index values. The associations between categorical and numeric variables were identified using Pearson's chi-square test and the Mann-Whitney, respectively.RESULTS: Co-expression of pAKT and PTEN was presented in 59 (56.7%) cases. Reduced levels of PTEN expression were detected in 20 (19.2%) cases, and these 20 tumors had a lower Ki-67 index value. In contrast, tumors positive for pAKT expression [71 (68.3%)] were associated with a higher Ki-67 index value.CONCLUSION: A role for AKT in the proliferation of HER2-positive breast cancers was confirmed. However, immunohistochemical detection of PTEN expression did not correlate with an inhibition of cellular proliferation or control of AKT phosphorylation, suggesting other pathways in these mechanisms of control.
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Munasarjasyöpä on Suomessa tappavin ja toiseksi yleisin gynekologinen syöpä, lisäksi se on kymmenenneksi yleisin naisten syöpä. Yli 90% munasarjasyövistä on epiteeliperäisiä ja morfologisista alatyypeistä yleisin on seroosi syöpä. Serooseista syövistä yli 90 % on korkean riskin eli high grade –syöpää. Vaikka uudet hoidot ovat pidentäneet potilaan selviytymistä, niin kaiken kaikkiaan kokonaisennuste ei kuitenkaan ole parantunut viimeisen vuosikymmenen aikana. Aikaisin havaittu paikallinen epiteeliperäinen munasarjasyöpä on parannettavissa kirurgialla. Yli 2/3 epiteliaalisista munasarjasyövistä diagnosoidaan vasta levinneessä vaiheessa, jolloin viiden vuoden selviytyvyys potilailla on vain noin 30 %. Aiemmin munasarjasyöpien arveltiin olevan lähtöisin munasarjojen pintaepiteelistä, mutta uusimpien tutkimusten mukaan kyseessä on niin molekulaarisesti kuin etiologisesti ryhmä eri syöpiä, jotka ilmenevät samassa anatomisessa paikassa. Syventävässä työssäni tutkin munasarjasyövän käyttäytymistä ennustavia merkkiaineita Merkkiaineita tutkimalla pyritään tulevaisuudessa ennustamaan paremmin syöpien käyttäytymistä ja antamaan potilaille parempia täsmähoitoja. Syventävien opintojeni tarkoituksena oli tutkia munasarjasyöpää kirjallisuuteen tutustumalla ja tutkimalla retrospektiivistä vuosien 2001–2007 munasarjapotilasaineistoa. Keräsimme toisen tutkijan kanssa aineistoon 356 potilaan tiedot, joista 310 sisällytettiin tekemiini tilastoihin. Lisäksi tutkin kiinnostavia munasarjasyövän käyttäytymiseen mahdollisesti liittyviä merkkiaineita (EGFR, HER2, P53 JA ALDH1) uudessa 48 potilaan aineistossa ja selvitin proteiinien merkitystä taudin kulussa ja ennusteessa. 310 potilaan aineiston tulokset olivat sopusoinnussa aiempiin julkaisuihin. Aineistomme munasarjasyövistä 60 % on seroosia high grade –syöpää ja 67 % syövistä on levinneen vaiheen eli luokan III-IV tauteja. 48 potilaan immunohistokemiallisissa värjäyksissä mielenkiintoisin tulos on se, että Her2 :n värjäytymisintensiteetti korreloi kääntäen vahvaan ALDH1-värjäykseen eli se on korkea, kun ALDH1 on matala (korrelaatio -0.425; p=0.00994) Vastaavasti Her2 :n intensiteetin ollessa korkea ALDH1/heikko-soluja on paljon (p=0.00975). Tällaista tutkimus tulosta ei aiemmin ole esitetty. Tämä kiinnostava tulos tulee jatkossa varmistaa laajemmassa aineistossa.
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Human epidermal growth factor receptor 2 (HER2) has been evaluated in breast cancer patients to identify those most likely to benefit from herceptin-targeted therapy. HER2 amplification, detected in 20-30% of invasive breast tumors, is associated with reduced survival and metastasis. The most frequently used technique for evaluating HER2 protein status as a routine procedure is immunohistochemistry (IHC). HER2 copy number alterations have also been evaluated by fluorescence in situ hybridization (FISH) in moderate immunoexpression (IHC 2+) cases. An alternative procedure to evaluate gene amplification is chromogenic in situhybridization (CISH), which has some advantages over FISH, including the correlation between HER2 status and morphological features. Other methodologies have also been used, such as silver-enhanced in situ hybridization (SISH) and quantitative real-time RT-PCR, to determine the number of HER2 gene copies and expression, respectively. Here we will present a short and comprehensive review of the current advances concerning HER2 evaluation in human breast cancer.
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Neoadjuvant chemotherapy has practical and theoretical advantages over adjuvant chemotherapy strategy in breast cancer (BC) management. Moreover, metronomic delivery has a more favorable toxicity profile. The present study examined the feasibility of neoadjuvant metronomic chemotherapy in two cohorts [HER2+ (TraQme) and HER2− (TAME)] of locally advanced BC. Twenty patients were prospectively enrolled (TraQme, n=9; TAME, n=11). Both cohorts received weekly paclitaxel at 100 mg/m2 during 8 weeks followed by weekly doxorubicin at 24 mg/m2 for 9 weeks in combination with oral cyclophosphamide at 100 mg/day (fixed dose). The HER2+ cohort received weekly trastuzumab. The study was interrupted because of safety issues. Thirty-six percent of patients in the TAME cohort and all patients from the TraQme cohort had stage III BC. Of note, 33% from the TraQme cohort and 66% from the TAME cohort displayed hormone receptor positivity in tumor tissue. The pathological complete response rates were 55% and 18% among patients enrolled in the TraQme and TAME cohorts, respectively. Patients in the TraQme cohort had more advanced BC stages at diagnosis, higher-grade pathological classification, and more tumors lacking hormone receptor expression, compared to the TAME cohort. The toxicity profile was also different. Two patients in the TraQme cohort developed pneumonitis, and in the TAME cohort we observed more hematological toxicity and hand-foot syndrome. The neoadjuvant metronomic chemotherapy regimen evaluated in this trial was highly effective in achieving a tumor response, especially in the HER2+ cohort. Pneumonitis was a serious, unexpected adverse event observed in this group. Further larger and randomized trials are warranted to evaluate the association between metronomic chemotherapy and trastuzumab treatment.
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Chez la souris, la thérapie anti-HER2 est dépendante de la présence de cellules T CD8+IFN-γ+ et des réponses IFN de type I. Ces IFN sont induits par les TLRs suite à la reconnaissance de signaux de danger, appelés PAMPs et DAMPs. Les TLR-3 et TLR-9 sont tous deux de bons inducteurs d’IFN de type I et sont également capable d’agir en synergie afin d’augmenter les niveaux d’IFN-γ, de TNF-α et d’IL-12. Notre hypothèse fut que la stimulation de ces deux TLRs mènerait à l’amélioration de l’activité anti-tumorale du trastuzumab via le recrutement et l’activation des cellules immunitaires. Nos buts furent de confirmer le potentiel thérapeutique de la combinaison de l’anticorps anti-HER2, de l’agoniste de TLR-3, le poly(I:C), et de l’agoniste de TLR-9, le CpG ODN. Des études in vivo et in vitro nous ont permis de découvrir une synergie entre ces agents qui résulte en une cytotoxicité ciblée plus efficace. De plus, cette thérapie s’avéra efficace chez des modèles CD8-dépendants et CD8-indépendents. Les souris purent rejeter leur tumeur et demeurer sains plusieurs semaines après l’arrêt des injections. Ces souris étaient également protégées lors d’un challenge, soulignant ainsi la présence d’une immunité mémoire. Nous avons aussi découvert que l’administration combine de trastuzumab des deux agonistes de TLRs mène à des réponses systémiques. Des études de déplétion confirmèrent que les cellules T CD8+ sont cruciales pour la protection à long terme des animaux, mais que les pDC sont moins impliquées que ce que l’on pourrait croire. Leur absence n’a que modestement affecté les effets de notre thérapie. À l’opposé, les cellules NK sont d’importants médiateurs des effets thérapeutiques. Des expériences d’ADCC ont révélé que le CpG ODN et poly(I:C) ont tous deux la capacité d’améliorer les fonctions des cellules NK, mais que la stimulation simultanée des TLR-3 et TLR-9 permet de maximiser les effets bénéfiques du trastuzumab. De la même manière, l’addition de CpG ODN et de poly(I:C) aux anticorps anti-HER2 a permis d’augmenter les réponses pro-inflammatoires, plus spécifiquement l’IFN-γ, le TNF-α, l’IP-10 et l’IL-12.
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This study covers an area of great importance in the research of breast cancer, related to the study of the effects of both estrogens (E2) and anti-estrogens (Tamoxifen) on chromosomes and of modulation of gene expression. Considering that breast cancer is a very heterogeneous disease and that patients respond differently to treatment, the identification of chromosomal abnormalities as well as genes responsive to 17β-estradiol (E2) and Tamoxifen (TAM) could provide the necessary framework to understand the complex effects of this hormone in target cells and could explain, at least in part, the development of cellular resistance to TAM treatment and the subsequent best therapeutic option. In this order of ideas, we determined the effects of E2 and TAM on the chromosomes and on the modulation of gene expression in four breast cancer cell lines, which represent three of the five subtypes of breast cancer known at present. The results are presented in six chapters - each one has a group of the results achieved around the cytogenetic characteristics and gene expression profiles of four cell lines and the effects of E2 and TAM incubation on those. The first chapter describes the main features of breast cancer, furthering the use and effects of E2 and TAM treatment.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Human epidermal growth factor receptor 2 (HER2) has been evaluated in breast cancer patients to identify those most likely to benefit from herceptin-targeted therapy. HER2 amplification, detected in 20-30% of invasive breast tumors, is associated with reduced survival and metastasis. The most frequently used technique for evaluating HER2 protein status as a routine procedure is immunohistochemistry (IHC). HER2 copy number alterations have also been evaluated by fluorescence in situ hybridization (FISH) in moderate immunoexpression (IHC 2+) cases. An alternative procedure to evaluate gene amplification is chromogenic in situ hybridization (CISH), which has some advantages over FISH, including the correlation between HER2 status and morphological features. Other methodologies have also been used, such as silver-enhanced in situ hybridization (SISH) and quantitative real-time RT-PCR, to determine the number of HER2 gene copies and expression, respectively. Here we will present a short and comprehensive review of the current advances concerning HER2 evaluation in human breast cancer.
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In this paper, we report the development of a sensitive label-free impedimetric biosensor based on the use of affibody as bioreceptor and gold nanostructured screen-printed graphite as a sensor platform for the detection of human epidermal growth factor receptor 2 (HER2). The affisensor is realized by immobilizing a terminal cysteine-modified affibody on gold nanoparticles. The sensor was characterized by electrochemical techniques and scanning electron microscopy (SEM). Furthermore, surface plasmon resonance (SPR) technology was also applied to explore the potential of affibodies as small-molecule discriminating tools. Using optimized experimental conditions, a single-use affisensor showed a good analytical performance for HER2 detection from 0 to 40μg/L. The estimated limit of detection was 6.0μg/L. Finally, the realized affisensor was applied to human serum samples.
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Purpose Sorafenib is a multikinase inhibitor with antiangiogenic/antiproliferative activity. A randomized, double-blind, placebo-controlled phase IIB trial assessed sorafenib with capecitabine for locally advanced or metastatic human epidermal growth factor receptor 2 (HER2) -negative breast cancer. Patients and Methods Patients were randomly assigned to first-or second-line capecitabine 1,000 mg/m(2) orally twice a day for days 1 to 14 of every 21-day cycle with sorafenib 400 mg orally twice a day or placebo. The primary end point was progression-free survival (PFS). Results In total, 229 patients were enrolled. The addition of sorafenib to capecitabine resulted in a significant improvement in PFS versus placebo (median, 6.4 v 4.1 months; hazard ratio [HR], 0.58; 95% CI, 0.41 to 0.81; P = .001) with sorafenib favored across subgroups, including first-line (HR, 0.50; 95% CI, 0.30 to 0.82) and second-line (HR, 0.65; 95% CI, 0.41 to 1.04) treatment. There was no significant improvement for overall survival (median, 22.2 v 20.9 months; HR, 0.86; 95% CI, 0.61 to 1.23; P = .42) and overall response (38% v 31%; P = .25). Toxicities (sorafenib v placebo) of any grade included rash (22% v 8%), diarrhea (58% v 30%), mucosal inflammation (33% v 21%), neutropenia (13% v 4%), hypertension (18% v 12%), and hand-foot skin reaction/hand-foot syndrome (HFSR/HFS; 90% v 66%); grade 3 to 4 toxicities were comparable between treatment arms except HFSR/HFS (44% v 14%). Reasons for discontinuation in the sorafenib and placebo arms included disease progression (63% v 82%, respectively), adverse events (20% v 9%, respectively), and death (0% v 1%, respectively). Conclusion Addition of sorafenib to capecitabine improved PFS in patients with HER2-negative advanced breast cancer. The dose of sorafenib used in this trial resulted in unacceptable toxicity for many patients. A phase III confirmatory trial has been initiated with a reduced sorafenib dose.
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Aims Human epidermal growth factor receptor 2 (HER2)-positive breast cancers are aggressive neoplasms associated with a variable response to systemic therapies. Therefore, the identification of biomarkers to better characterise this heterogeneity would improve treatment efficacy. The aim of this study was to evaluate the influence of androgen receptor (AR) and oestrogen receptor (ER) on clinicopathological features in a series of HER2-positive breast carcinomas. Methods A total of 104 carcinomas were selected and reviewed. Immunohistochemical studies for ER, progesterone receptor and Ki-67 were analysed on tumour whole histological sections. AR expression was analysed on samples represented on tissue microarrays. According to steroid receptor expression, cases were classified into three groups: AR positive/ER positive (48 cases), AR positive/ER negative (41 cases) and AR negative/ER negative (13 cases). Results AR-positive tumours corresponded to 89 (85.6%) of 104 carcinomas. AR-positive carcinomas were associated with a higher frequency of ER and progesterone receptor co-expression and lower proliferative activity determined by the expression of Ki-67. AR-negative carcinomas were more often high grade. The group of AR-positive/ER-negative carcinomas was associated with the highest frequency of apocrine morphological features. The group of AR-negative/ER-negative carcinomas was associated with the highest proliferative activity and the highest frequency of high histological and nuclear grade. The lowest frequency of high-grade tumours and the lowest proliferative activity were seen among tumours with expression of both receptors. Conclusions These results suggest that co-expression of AR and ER can provide a protective effect based on phenotypical presentation of HER2-positive carcinomas. Furthermore, lack of both steroid hormone receptors characterises the most aggressive phenotype.