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HER2
Terms modified by HER2 Selected AbstractsFluorescence lifetime imaging of activatable target specific molecular probesCONTRAST MEDIA & MOLECULAR IMAGING, Issue 1 2010Raphael Alford Abstract In vivo optical imaging using fluorescently labeled self-quenched monoclonal antibodies, activated through binding and internalization within target cells, results in excellent target-to-background ratios. We hypothesized that these molecular probes could be utilized to accurately report on cellular internalization with fluorescence lifetime imaging (FLI). Two imaging probes were synthesized, consisting of the antibody trastuzumab (targeting HER2/neu) conjugated to Alexa Fluor750 in ratios of either 1:8 or 1:1. Fluorescence intensity and lifetime of each conjugate were initially determined at endosomal pHs. Since the 1:8 conjugate is self-quenched, the fluorescence lifetime of each probe was also determined after exposure to the known dequencher SDS. In vitro imaging experiments were performed using 3T3/HER2+ and BALB/3T3 (HER2,) cell lines. Changes in fluorescence lifetime correlated with temperature- and time-dependent cellular internalization. In vivo imaging studies in mice with dual flank tumors [3T3/HER2+ and BALB/3T3 (HER2,)] detected a minimal difference in FLI. In conclusion, fluorescence lifetime imaging monitors the internalization of target-specific activatable antibody,fluorophore conjugates in vitro. Challenges remain in adapting this methodology to in vivo imaging. Copyright © 2010 John Wiley & Sons, Ltd. [source] The effects of antibody clone and pretreatment method on the results of HER2 immunostaining in cytologic samples of metastatic breast cancer: A query and a review of the literature,,§DIAGNOSTIC CYTOPATHOLOGY, Issue 6 2007Patricia A. Fetsch M.T. (ASCP) Abstract The standardization and use of heat-induced epitope retrieval (HIER) is particularly important with immunohistochemical markers that direct the course of cancer treatment, such as Herceptin therapy. Increasingly, many laboratories are performing immunohistochemical analysis using various antibodies and methodologies for HER2/neu. We attempted to determine the effects of antibody clone and pretreatment methods on the interpretation of HER-2/neu staining in cytologic samples. Cell block sections from 54 cases of metastatic breast cancer (24 FNAs, 30 effusions) were analyzed for HER2 expression using antibodies to CB-11, TAB250, and A0485. Antibodies were analyzed with and without HIER. One pathologist using the FDA-approved scoring system for the HercepTest reviewed all slides in a blinded fashion. Five of fifty-four cases (9%) using CB-11 showed a significant increase in HER2 immunoreactivity using HIER (i.e. from 0/1+ to 2,3+). However, in twenty-nine of fifty-four cases (54%), the cytoplasmic background was significantly higher after HIER. With the A0485 antibody, two of fifty four cases (4%) showed a significant increase in immunoreactivity using HIER, while seventeen of fifty-four cases (31%) exhibited only more pronounced cytoplasmic staining. HIER pretreatment did not increase HER2 staining in any TAB250 stained sample, rather four of fifty-four cases (7%) showed a significant decrease in staining with HIER. We conclude that HIER may enhance membrane staining with the CB-11 and A0485 antibodies, but also increases cytoplasmic background. Loss of antigenicity is seen when HIER is used with TAB250. Diagn. Cytopathol. 2007;35:319,328. © 2007 Wiley-Liss, Inc. [source] Prognostic significance of tumor angiogenesis, Ki 67, p53 oncoprotein, epidermal growth factor receptor and HER2 receptor protein expression in undifferentiated nasopharyngeal carcinoma,a prospective study,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 10 2003Brigette B. Y. Ma FRACP Abstract Background. This study prospectively examines the prognostic role of p53 oncoprotein (p53), Ki67-antigen (Ki67), tumor angiogenesis (MVD), epidermal growth factor receptor (EGFR), and HER2 receptor protein (HER2) expression in Chinese with undifferentiated nasopharyngeal carcinoma (NPC). Methods. Seventy-eight Chinese were recruited from October 1995 to July 1997 at the Prince of Wales Hospital, Hong Kong. Pretreatment immunohistochemical preparations of the primary tumor were made, and clinical data were collected prospectively until October 30, 2000. The markers were correlated with overall survival (OS), disease-free survival (DFS), time to progression (TTP), and UICC stage. Results. On univariate analysis, EGFR expression correlated with poorer OS (p = .0001), DFS (p = .01), shorter TTP (p = .0001), and advanced T stage (p = .036). Strong EGFR expression, when compared with weak or moderate, was associated with poorer OS (p = .04) and shorter TTP in a subgroup of patients with UICC stage III,IV disease. HER2 expression was associated with advanced UICC stage (p = .006). The presence of p53 expression correlated with poorer DFS (p = .01) and a trend toward shorter TTP (p = .06). No correlation was found with Ki67-antigen or MVD. On multivariate analysis, only EGFR expression was significantly linked to shorter OS and TTP. Conclusions. EGFR expression in undifferentiated NPC is associated with a poor clinical outcome. A prognostic role of p53 and HER2 expression is suggestive but not consistently defined in this study. The relatively high prevalence of positive staining for EGFR supports the use of molecular targeted therapy in this disease. © 2003 Wiley Periodicals, Inc. Head and Neck 25: 864,872, 2003 [source] Centrally necrotizing carcinoma of the breast: clinicopathological analysis of 33 cases indicating its basal-like phenotype and poor prognosisHISTOPATHOLOGY, Issue 2 2010Lin Yu Yu L, Yang W, Cai X, Shi D, Fan Y & Lu H (2010) Histopathology,57, 193,201 Centrally necrotizing carcinoma of the breast: clinicopathological analysis of 33 cases indicating its basal-like phenotype and poor prognosis Aims:, To investigate the clinicopathological features and immunophenotype of centrally necrotizing carcinoma (CNC) of the breast to ascertain its relationship to basal-like phenotype and its prognosis. Methods and results:, The clinical and pathological characteristics of 33 CNCs were reviewed. Immunohis-tochemical study of oestrogen receptor, progesterone receptor, HER2, cytokeratin (CK) 8/18, high-molecular-weight CK (34,E12), CK5/6, CK14, CK17, smooth muscle antigen, p63, vimentin and epidermal growth factor receptor was performed. The striking feature of CNC was a central, necrotic or acellular zone surrounded by a ring-like area of viable tumour cells. The central zone showed three morphological types: predominance of coagulative necrosis (21 cases), predominance of fibrosis and scar tissue (nine cases) and infarction (three cases). Tumour cells displayed invasive ductal carcinoma of high grade. The expression rate of basal-like markers was higher than that of myoepithelial markers (87.9% versus 46.2%). Basal-like subtype was shown by 63.6% of cases. The expression rate of CK5/6 (90.5%) was highest among basal-like markers. Follow-up data of 19 patients were available. Median progression-free survival was 15.5 months. In 12 patients (63.2%), local recurrence and/or distant metastasis developed (median time to recurrence and/or metastasis, 14.0 months). Conclusions:, CNC has distinctive morphological features, which mostly exhibit a basal-like immunophenotype and poor prognosis. CNC is a typical representative of basal-like breast cancer. [source] Distinguishing medullary carcinoma of the breast from high-grade hormone receptor-negative invasive ductal carcinoma: an immunohistochemical approachHISTOPATHOLOGY, Issue 7 2010Uta Flucke Flucke U, Flucke M T, Hoy L, Breuer E, Goebbels R, Rhiem K, Schmutzler R, Winzenried H, Braun M, Steiner S, Buettner R & Gevensleben H (2010) Histopathology,56, 852,859 Distinguishing medullary carcinoma of the breast from high-grade hormone receptor-negative invasive ductal carcinoma: an immunohistochemical approach Aims:, Medullary carcinomas (MCs) represent a rare breast cancer subtype associated with a rather favourable prognosis compared with invasive ductal carcinomas (IDCs). Due to histopathological overlap, MCs are frequently misclassified as high-grade IDCs, potentially leading to overtreatment of MCs. Our aim was to establish novel diagnostic markers distinguishing MCs from hormone receptor-negative high-grade IDCs. Methods and results:, Sixty-one MCs and 133 hormone receptor-negative IDCs were analysed in a comparative immunohistochemical study. Applied markers included a comprehensive panel of cytokeratins (CKs), vimentin, smooth muscle actin (SMA), p63, p53, cell adhesion molecules [N-CAM (CD56), syndecan-1 (CD138), E-cadherin and P-cadherin] and development associated transcription factors (AP-2,, AP-2,). A significantly higher proportion of IDCs displayed increased expression of CK7, AP-2, and HER2 in contrast to MCs (CK7: 91% of IDCs versus 77% of MCs; AP-2,: 77% versus 57%; and HER2: 26% versus 7%, each P < 0.01). Vice versa, MCs were slightly more frequently positive for SMA and vimentin (P > 0.05). Conclusions:, Hormone receptor-negative high-grade IDCs are significantly associated with luminal differentiation, Her2 and AP-2, overexpression, whereas MCs tend to display myoepithelial features. Markers analysed in this study are of diagnostic value regarding the differential diagnosis of MCs. [source] Understanding the HER family in breast cancer: interaction with ligands, dimerization and treatmentsHISTOPATHOLOGY, Issue 5 2010Fabrício F T Barros Barros F F T, Powe D G, Ellis I O & Green A R (2010) Histopathology56, 560,572 Understanding the HER family in breast cancer: interaction with ligands, dimerization and treatments Breast carcinoma is the most frequent type of cancer affecting women. Among the recently described molecular and phenotypic classes of breast cancer, human epidermal growth factor receptor 2 (HER2)-positive tumours are associated with a poor prognosis. HER2 plays an important role in cancer progression being targeted to provide predictive and prognostic information. Moreover, HER2 is related to cancer resistance against a variety of therapies; however, trastuzumab (herceptin) has proved successful in treatment of this subgroup. Nevertheless, resistance to this drug may be acquired by patients after a period of treatment, which indicates that other molecular mechanisms might influence success of this therapy. Dimerization between members of the HER family may contribute to resistance against treatments due to different combinations that trigger different downstream pathways. This is promoted by ligands, which are expressed as transmembrane precursor protein molecules and have a conserved epidermal growth factor-like domain. Through resistance to trastuzumab, other drugs are being developed to interact in different domains of HER2 protein. It might be a good strategy to apply new drugs simultaneously to trastuzumab due to act in different domains of HER2. The study of interaction between receptors/ligands will characterize specifically their signalling pathway and understand which strategy to acquire. [source] Assessment of a HER2 scoring system for gastric cancer: results from a validation studyHISTOPATHOLOGY, Issue 7 2008M Hofmann Aims:, Human epidermal growth factor receptor 2 (HER2) overexpression/amplification is implicated in the development of various solid tumour types. Validated methods and scoring systems for evaluating HER2 status exist in breast cancer, but not in gastric cancer. The aim was to establish a HER2 scoring system for gastric cancer to identify suitable patients for enrolment in a trial of trastuzumab (Herceptin®) in advanced metastatic gastric cancer. Methods and results:, Formalin-fixed paraffin-embedded gastric cancer samples were tested for HER2 status using the fluorescence in situ hybridization (FISH) pharmDxÔ kit (Dako Denmark A/S). Immunohistochemistry (IHC) was performed using the HercepTestÔ (Dako). Concordance between FISH and IHC was 93.5% in 168 evaluable samples. Eleven samples were scored as FISH+ but IHC, or equivocal. Conclusions:, IHC/FISH discrepancies were attributed to basolateral membranous immunoreactivity of glandular cells resulting in incomplete membranous reactivity and/or a higher rate of tumour heterogeneity in gastric cancer compared with breast cancer. With modifications to the IHC scoring system, the HercepTestÔ is considered valid for the identification of HER2+ gastric tumours for this clinical trial. Correlation of HER2 scores with clinical outcomes will be needed to determine which patients might benefit from trastuzumab therapy. [source] Metaplastic breast carcinomas are basal-like tumoursHISTOPATHOLOGY, Issue 1 2006J S Reis-Filho Aims :,Recently, an immunohistochemical panel comprising antibodies against HER2, oestrogen receptor (ER), epidermal growth factor receptor (EGFR) and cytokeratin (CK) 5/6 was reported to identify basal-like breast carcinomas, as defined by cDNA microarrays. Our aim was to analyse a series of metaplastic breast carcinomas (MBCs) using this panel plus two other basal markers (CK14 and p63) and progesterone receptor (PR), to define how frequently MBCs show a basal-like immunophenotype. Methods and results :,Sixty-five cases were retrieved from the pathology archives of the authors' institutions and reviewed by three of the authors. Immunohistochemistry with antibodies for HER2, ER, EGFR, CK5/6, CK14 and p63 was performed according to standard methods. All but six cases (91%) showed the typical immunoprofile of basal-like tumours (ER, and HER2,, EGFR+ and/or CK5/6+). When CK14 and p63 were added to the panel, two additional cases could be classified as basal-like. The majority of MBCs lacked PR, except 4/19 (21%) carcinomas with squamous metaplasia. Conclusions :,Our results demonstrate that MBCs show a basal-like phenotype, regardless of the type of metaplastic elements. Moreover, as these neoplasms frequently overexpress EGFR (57%), patients with MBC may benefit from treatment with anti-EGFR drugs. [source] Treatment outcomes and clinicopathologic characteristics of triple-negative breast cancer patients who received platinum-containing chemotherapyINTERNATIONAL JOURNAL OF CANCER, Issue 6 2009Ji Eun Uhm Abstract The aim of this study was to evaluate the role of platinum-containing chemotherapy for metastatic triple-negative breast cancer (TNBC) patients in terms of the response rate (RR) and progression-free survival. A second aim was to characterize the clinical behavior at the time of relapse of TNBC. We retrospectively analyzed the clinical outcomes of patients with metastatic breast cancer who received taxane,platinum chemotherapy as the first- or second-line treatment, focusing on the TN phenotype. In total, 257 patients with metastatic breast cancer received platinum-containing chemotherapy at Samsung Medical Center from 1999 to 2006. Of these patients, 106 patients with available data on estrogen (ER), progesterone (PgR) and human epidermal growth factor receptor-2 (HER2) receptor status received taxane,platinum regimen as the first- or second-line treatment. The overall RR of patients with TNBC was 39%. This rate did not differ significantly from those of patients with other phenotypes. The time to death after chemotherapy (19 vs. 50 months, p = 0.037) and overall survival (OS) (21 vs. 56 months, p = 0.030) differed significantly between patients with TNBC and non-TNBC. TNBC showed a unique locoregional infiltration pattern at relapse, which might reflect its aggressive clinical behavior. Despite the similar response to platinum-containing chemotherapy, patients with TNBC had a shorter OS than patients with non-TNBC. The implication of TN phenotype as poor prognostic factor is uncertain, because it needs to be defined whether poor outcome is related to the rapid growing characteristics of tumor itself or the resistance to drug therapy. Further prospective studies are warranted. © 2008 Wiley-Liss, Inc. [source] Chemoresistant tumor cell lines display altered epidermal growth factor receptor and HER3 signaling and enhanced sensitivity to gefitinibINTERNATIONAL JOURNAL OF CANCER, Issue 12 2008Tiziana Servidei Abstract Deregulated signaling through the epidermal growth factor receptor (EGFR) is involved in chemoresistance. To identify the molecular determinants of sensitivity to the EGFR inhibitor gefitinib (Iressa, ZD1839) in chemoresistance, we compared the response of matched chemosensitive and chemoresistant glioma and ovarian cancer cell lines. We found that chemoresistant cell lines were 2- to 3-fold more sensitive to gefitinib growth-inhibitory effects, because of decreased proliferation rather than survival. Sensitivity to gefitinib correlated with overexpression and constitutive phosphorylation of HER2 and HER3, but not EGFR, altered HER ligand expression, and enhanced activation of EGF-triggered EGFR pathway. No activating mutations were found in EGFR. Gefitinib fully inhibited EGF-induced and constitutive Akt activation only in chemoresistant cells. In parallel, gefitinib downregulated constitutively phosphorylated HER2 and HER3, and activated GSK3, with a concomitant degradation of cyclin D1. Ectopically overexpressed HER2 on its own was insufficient to sensitize chemonaive cells to gefitinib. pHER3 coimmunoprecipitated with p85-PI3K in chemoresistant cells and gefitinib dissociated these complexes. siRNA-mediated inhibition of HER3 decreased constitutive activation of Akt and sensitivity to gefitinib in chemoresistant cells. Our study indicates that in chemoresistant cells gefitinib inhibits both an enhanced EGF-triggered pathway and a constitutive HER3-mediated Akt activation, indicating that inhibition of HER3 together with that of EGFR could be relevant in chemorefractory tumors. Furthermore, in combination experiments gefitinib enhanced the effects of coadministered drugs more in chemoresistant than chemosensitive ovarian cancer cells. Combined treatment might be therapeutically beneficial in chemoresistant tumors from ovary and likely from other tissues. © 2008 Wiley-Liss, Inc. [source] Impact of HER2 and EGFR gene status on gefitinib-treated patients with nonsmall-cell lung cancer,INTERNATIONAL JOURNAL OF CANCER, Issue 5 2007Junichi Soh Abstract We previously examined the relationship between epidermal growth factor receptor (EGFR) status and clinical outcomes of nonsmall-cell lung cancer (NSCLC) patients treated with gefitinib. In our study, we additionally examined HER2 status and investigate the impact of genetic status as predictors in Japanese NSCLC patients treated with gefitinib. The HER2 copy number status was determined by fluorescence in situ hybridization assay and mutation of HER2 exon 20 was determined by direct sequencing in 74 patients to investigate the relationship between molecular statuses including HER2 and EGFR and the clinical outcomes of patients treated with gefitinib. The high HER2 copy number was identified in 32 (43.2%) of 74 NSCLC patients and no HER2 exon 20 mutations were found. The high HER2 copy number was significantly associated with the sensitivity to gefitinib (p = 0.0045) and a prolonged progression-free survival (PFS) (p = 0.0089) in a univariate analysis, but not in a multivariate analysis. Multivariate analyses exhibited that the drug-sensitive EGFR mutation was an independent predictive factor of a better sensitivity to gefitinib (OR = 41.9, p = 0.002), prolonged overall survival (HR = 0.32, p = 0.019) and PFS (HR = 0.31, p = 0.0045). The high EGFR copy number might have a weak association with better response and prognosis without statistical significance. In conclusion, the drug-sensitive EGFR mutation, rather than HER2 and EGFR copy numbers, is a determinant of favorable clinical outcomes in gefitinib-treated patients with NSCLC, although the high HER2 copy number, to some extent, may influence the gefitinib effect. © 2007 Wiley-Liss, Inc. [source] Small interfering RNA (siRNA) inhibits the expression of the Her2/neu gene, upregulates HLA class I and induces apoptosis of Her2/neu positive tumor cell linesINTERNATIONAL JOURNAL OF CANCER, Issue 1 2004Aniruddha Choudhury Abstract Silencing of a specific mRNA using double stranded RNA oligonucleotides represents one of the newest technologies for suppressing a specific gene product. Small interfering RNA (siRNA) are 21 nucleotides long, double stranded RNA fragments that are identical in sequence to the target mRNA. We designed 3 such siRNA against the Her2/neu (HER2) gene. The HER2 gene is known to play an important role in the oncogenesis of several types of cancers, such as breast, ovarian, colon and gastric cancers. Introduction of the siRNA into HER2 positive tumor lines in vitro greatly reduced the cell surface expression of the HER2 protein. Concurrently, a range of effects on cell physiology, such as growth inhibition or apoptosis, was observed. The expression of HLA class I was observed to be upregulated when HER2 was silenced with siRNA. Treatment of SKBr3 and MCF7/HER2 tumor cell lines with the HER2 siRNA resulted in growth arrest of cells in the late G1/S-phase. Our results suggest that siRNA may be an effective method of abrogating the effect of HER2 in tumorigenesis. © 2003 Wiley-Liss, Inc. [source] Safety and efficacy of the combination of trastuzumab with docetaxel for HER2-positive women with advanced breast cancer.INTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 6 2004A review of the existing clinical trials, results of the expanded access programme in the UK Summary Trastuzumab is a humanised monoclonal antibody against the extracellular domain of HER2 (human epidermal growth factor receptor-2) that is overexpressed in about 25% of human breast cancers. It has shown clinical benefit in HER2-positive breast cancer cases when used alone or in combination with chemotherapy. Trastuzumab increases the response rate to chemotherapy and prolongs survival when used in combination with taxanes. In this article, we review the clinical trials where trastuzumab has been administered together with docetaxel, and we present the results of the trastuzumab expanded access programme (EAP) in the UK. Combination of trastuzumab with docetaxel results in similar response rates and time-to-progression with the trastuzumab/paclitaxel combinations. The toxicity of the combination and the risk of heart failure are low. The clinical data for the docetaxel/trastuzumab combination indicate a favourable profile from both the efficacy and the safety point of view and confirm the feasibility and safety of trastuzumab administration both as monotherapy and in combination with docetaxel. [source] Shed HER2 extracellular domain in HER2-mediated tumor growth and in trastuzumab susceptibility,JOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2010Gaia C. Ghedini The question of the serum HER2 extracellular domain (HER2/ECD) measurement for prediction of response to the anti-HER2 antibody Trastuzumab is still an open and current matter of clinical debate. To elucidate the involvement of shed HER2/ECD in HER2-driven tumor progression and in guiding therapy of individual patients, we examined biological effects exerted by elevated HER2/ECD in cancer growth and in response to Trastuzumab. To this purpose SKOV3 tumor cells were stably transfected to release a recombinant HER2/ECD molecule (rECD). Transfectants releasing high levels of 110-kDa rECD, identical in size to native HER2/ECD (nECD), grew significantly slower than did controls, which constitutively released only basal levels of nECD. While transmembrane HER2 and HER1 were expressed at equal levels by both controls and transfected cells, activation of these molecules and of downstream ERK2 and Akt was significantly reduced only in rECD transfectants. Surface plasmon resonance analysis revealed heterodimerization of the rECD with HER1, -2, and -3. In cell growth bioassays in vitro, shed HER2 significantly blocked HER2-driven tumor cell proliferation. In mice, high levels of circulating rECD significantly impaired HER2-driven SKOV3 tumor growth but not that of HER2-negative tumor cells. In vitro and in mice, Trastuzumab significantly inhibited tumor growth due to the rECD-facilitated accumulation of the antibody on tumor cells. Globally our findings sustain the biological relevance of elevated HER2/ECD levels in the outcome of HER2-disease and in the susceptibility to Trastuzumab-based therapy. J. Cell. Physiol. 225: 256,265, 2010. © 2010 Wiley-Liss, Inc. [source] Shepherding AKT and androgen receptor by Ack1 tyrosine kinaseJOURNAL OF CELLULAR PHYSIOLOGY, Issue 2 2010Kiran Mahajan Ack1 (also known as ACK, TNK2, or activated Cdc42 kinase) is a structurally unique non-receptor tyrosine kinase that is expressed in diverse cell types. It integrates signals from plethora of ligand-activated receptor tyrosine kinases (RTKs), for example, MERTK, EGFR, HER2, PDGFR and insulin receptor to initiate intracellular signaling cascades. Ack1 transduces extracellular signals to cytosolic and nuclear effectors such as the protein kinase AKT/PKB and androgen receptor (AR), to promote cell survival and growth. While tyrosine phosphorylation of AR at Tyr267 regulates androgen-independent recruitment of AR to the androgen-responsive enhancers and transcription of AR target genes to drive prostate cancer progression, phosphorylation of an evolutionarily conserved Tyrosine 176 in the kinase domain of AKT is essential for mitotic progression and positively correlates with breast cancer progression. In contrast to AR and AKT, Ack1-mediated phosphorylation of the tumor suppressor Wwox at Tyr287 lead to rapid Wwox polyubiquitination followed by degradation. Thus, by its ability to promote tumor growth by negatively regulating tumor suppressor such as Wwox and positively regulating pro-survival factors such as AKT and AR, Ack1 is emerging as a critical player in cancer biology. In this review, we discuss recent advances in understanding the physiological functions of Ack1 signaling in normal cells and the consequences of its hyperactivation in various cancers. J. Cell. Physiol. 224: 327,333, 2010. © 2010 Wiley-Liss, Inc. [source] HER2 signaling enhances 5,UTR-mediated translation of c-Myc mRNAJOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2004Enrico Galmozzi The increased levels of c-Myc protein observed previously in an ovarian carcinoma cell line stably transfected to express HER2 has suggested a role for the HER2 pathway in c-Myc expression. Analysis of HER2-transfected cells stimulated with heregulin ,1 (HRG) revealed increased c-Myc protein levels but not a corresponding increase in c-Myc mRNA expression or any change in c-Myc protein half-life. Transfection of HER2-overexpressing cells with a construct containing the 5, untranslated region (5,UTR) of c-Myc mRNA originated from the P2 promoter and placed upstream of the Renilla luciferase gene, enhanced reporter expression upon stimulation with HRG. The HRG-mediated increase in reporter activity correlated with the HRG-mediated induction observed for c-Myc protein, identifying the P2-derived leader (P2L) of c-Myc mRNA as the cis -element involved in c-Myc translational induction. Both the increase in c-Myc protein levels and P2L-enhanced translational activity were inhibited by the PI3K inhibitor wortmannin. Together, these results demonstrate that HRG stimulation of HER2 overexpressing cells leads to enhanced c-Myc protein synthesis through activation of the PI3K/Akt/mTOR pathway and that the P2L of c-Myc mRNA is the element responsible for induction of c-Myc translation. © 2004 Wiley-Liss, Inc. [source] Ethanol Enhances the Interaction of Breast Cancer Cells Over-Expressing ErbB2 With FibronectinALCOHOLISM, Issue 5 2010Mei Xu Background:, Ethanol is a tumor promoter and may enhance the metastasis of breast cancer. However, the underlying cellular/molecular mechanisms remain unknown. Amplification of ErbB2 or HER2, a receptor tyrosine kinase of the ErbB family, is found in 20 to 30% of patients with breast cancer. We have previously demonstrated that the effect of ethanol on the migration/invasion of breast cancer cells positively correlated with the expression levels of ErbB2. Adhesion to the extracellular matrix (ECM) is an important initial step for cancer cell invasion and metastasis. In this study, we investigated the effects of ethanol on the adhesion of MCF7 breast cancer cells over-expressing ErbB2 (MCF7ErbB2) to human plasma fibronectin. Methods:, To test the hypothesis that ethanol may enhance the attachment of human breast cancer cells to fibronectin, an important component of the ECM, we evaluated the effect of ethanol on the expression of focal adhesions, cell attachment, and ErbB2 signaling in cultured MCF7ErbB2 cells. Results:, Exposure to ethanol drastically enhanced the adhesion of MCFErbB2 cells to fibronectin and increased the expression of focal adhesions. Ethanol induced phosphorylation of ErbB2 at Tyr1248, FAK at Tyr861, and cSrc at Try216. Ethanol promoted the interaction among ErbB2, FAK, and cSrc, and the formation of a focal complex. AG825, a selective ErbB2 inhibitor, attenuated the ethanol-induced phosphorylation of ErbB2 and its association with FAK. Furthermore, AG825 blocked ethanol-promoted cell/fibronectin adhesion as well as the expression of focal adhesions. Conclusions:, Our results suggest that ethanol enhances the adhesion of breast cancer cells to fibronectin in an ErbB2-dependent manner, and the FAK pathway plays an important role in ethanol-induced formation of a focal complex. [source] Solamargine upregulation of Fas, downregulation of HER2, and enhancement of cytotoxicity using epirubicin in NSCLC cellsMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 8 2007Chia-Hua Liang Abstract Nonsmall-cell lung cancer (NSCLC) is not generally a chemosensitive tumor, and the mechanism of resistance to the relevant anticancer drugs has not been fully elucidated. Solamargine (SM), the major steroidal glycoalkaloids extracted from the Chinese herb Solanum, inhibits the growth of human tumor cells. We have previously demonstrated that SM regulates tumor necrosis factor receptors (TNFRs)- and mitochondria-mediated pathways and sensitizes NSCLC cells to initiate apoptosis. Interestingly, this investigation reveals that SM up-regulated Fas expression and down-regulated the expression of HER2, whose overexpression is associated with resistance to drugs, and promotes chemotherapy-induced apoptosis in NSCLC A549 and H441 cells. After treatment with SM, the expression of HER2 mRNA was correlated with the expression of topoisomerase II, (TOP2A) mRNA. The combinatory use of low concentrations of SM with low-toxic topoisomerase II inhibitor epirubicin accelerated apoptotic cell death. Therefore, the downregulation of the HER2 and TOP2A expression by SM with epirubicin may partially explain the SM and epirubicin cytotoxicity synergy effect in NSCLC. Results of this study suggest that SM induces Fas and TNFR-induced NSCLC cell apoptosis and reduces HER2 expression. These findings provide the synergistic therapeutic interaction between SM and epirubicin, suggesting that such combinations may be effectively exploited in future human cancer clinical trials. [source] Immunohistochemical analysis of receptor tyrosine kinase signal transduction activity in chordomaNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 1 2008J. H. Fasig Aims: Currently, there are no effective chemotherapeutic protocols for chordoma. Reports of receptor tyrosine kinase (RTK) expression in chordoma suggest that these tumours may respond to kinase inhibitor therapy. However, RTK signalling activity has not been extensively investigated in chordoma. Methods: A tissue microarray containing 21 cases of chordoma was analysed for expression of a number of proteins involved in signal transduction from RTKs by immunohistochemistry. Results: Platelet-derived growth factor receptor-,, epidermal growth factor receptor (EGFR), KIT and HER2 were detected in 100%, 67%, 33% and 0% of cases, respectively. Platelet-derived growth factor receptor-, staining was of moderate-to-strong intensity in 20 of 21 cases. In contrast, KIT immunoreactivity was weak and focal in each of the seven positive cases. Total EGFR staining was variable; weak staining for phosphorylated EGFR was detected in nine cases. Phosphorylated isoforms of p44/42 mitogen-activated protein kinase, Akt and STAT3, indicative of tyrosine kinase activity, were detected in 86%, 76% and 67% of cases, respectively. Conclusions: Chordomas commonly express RTKs and activated signal transduction molecules. Although there were no statistically significant correlations between the expression of any of the markers studied and disease-free survival or tumour location, the results nonetheless indicate that chordomas may respond to RTK inhibitors or modulators of other downstream signalling molecules. [source] Simultaneous imaging of membrane antigen and the corresponding chromosomal locus in pathology archivesPATHOLOGY INTERNATIONAL, Issue 12 2005Hisaki Igarashi A new procedure for the simultaneous staining of membranous antigens, such as tyrosine kinase-type cell surface receptor HER2 (c-erbB2), and the corresponding chromosome (chromosome 17 for c-erbB2) in the same cell for use in examining pathology archives is presented. A multistep procedure involving microwave-assisted fluorescence in situ hybridization and immunofluorescence yielded cell images having c-erbB2 on the membrane and genomic signals from the chromosome 17 centromere and the c-erbB2 locus. Furthermore, a combination of microwave-assisted chromogenic in situ hybridization and immunohistochemistry found colorized signals from both chromosome 17 centromere in the nuclei and c-erbB2 on the membranes of individual cells. Quantitative image analysis further confirmed the presence of a significantly stronger c-erbB2 immunoreactivity on cells containing three or more signals from chromosome 17 than from those with less than three signals. It was possible to extend the constellation of cell surface markers and corresponding chromosomes or locus-specific makers to several other genes including CDH1. In this case, the disappearances of CDH1 expression, a CDH1 locus signal, and a centromere enumeration probe (CEP) 16 signal were simultaneously demonstrated in the less-adhesive tumor cells. Thus, it is believed that this procedure might pave the way for exploiting pathology archives for the genotype,phenotype analysis of individual cells. [source] Degradation of HER2 Receptor Through Hypericin-mediated Photodynamic TherapyPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 1 2010Ján Kova Current treatment of breast cancer is often affected by resistance to therapeutics, for which the human epidermal growth factor receptor 2 (HER2) may be responsible. Here, we report for the first time the use of hypericin-mediated photodynamic therapy (HY-PDT) in combination with a selective HER2 inhibitor (AG 825) on SKBR-3, a HER2 overexpressing human breast adenocarcinoma cell line. The results demonstrate that HY-PDT is able to degrade HER2 with an impact on its signaling cascade. Combination with AG 825 resulted in increased apoptosis induction, total degradation of HER2 and inhibition of colony formation. Downregulation of HSP90, Mcl-1, Bcl-xL and upregulation of Bax was also observed. This knowledge provides the basis for the possible application of HY-PDT in preclinical and clinical models of breast cancer treatment. [source] Combination of immunohistochemistry and laser ablation ICP mass spectrometry for imaging of cancer biomarkersPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 18 2008Jaume Seuma Abstract Laser ablation (LA) ICP-MS has been developed as a new tool for imaging of cancer biomarkers in tissue sections. The distribution of two breast cancer-associated proteins, MUC-1 and HER2 was studied based on multiple line rastering of tissue sections and measurement of relevant Au/Ag tagged antibodies bound to the tissue. Comparisons with optical microscopy indicated extremely high sensitivity for the LA technique and sufficiently good resolution to permit fine scale feature mapping at the cellular level. Application to the quantitative assessment of HER2 expression in tissue microarrays was demonstrated. [source] Low expression of HER2 protein in breast cancer is biologically significantTHE JOURNAL OF PATHOLOGY, Issue 3 2006SM Tovey Abstract HER2 status is routinely tested using immunohistochemistry or FISH following the licensing of a therapeutic agent targeting HER2. However, neither of these methods provides quantitative information relating to the 70,80% of patients with levels of expression lower than the assay detection thresholds. In this study, radioimmunohistochemistry was used to detect quantitative HER2 protein expression in 178 breast cancers. Survival analysis was performed, as were correlations with known prognostic variables and with overexpression of other HER family members. It is demonstrated that the populations expressing very high and very low levels of HER2 are each associated with increased risk of cancer-specific death on survival analysis (p = 0.0043). The group with low levels of HER2 was more likely to be of higher grade, EGFR-positive and ER/HER3/HER4-negative. HER2-positive cases were frequently ER-negative/HER3-positive, whilst cases with normal HER2 expression were often ER-positive/HER4-positive. The aggressive nature of the tumour group with low HER2 expression may be explained by actions of other HER family members, particularly EGFR, but whether these or other factors have a negative regulatory effect on HER2 expression remains to be determined. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Pleomorphic lobular carcinoma of the breast: role of comprehensive molecular pathology in characterization of an entityTHE JOURNAL OF PATHOLOGY, Issue 1 2005Jorge S Reis-Filho Abstract Immunohistochemical analysis of E-cadherin has changed the way lobular neoplasia is perceived. It has helped to classify difficult cases of carcinoma in situ with indeterminate features and led to the identification of new variants of lobular carcinoma. Pleomorphic lobular carcinoma (PLC) and pleomorphic lobular carcinoma in situ (PLCIS), recently described variants of invasive and in situ classic lobular carcinoma, are reported to be associated with more aggressive clinical behaviour. Although PLC/PLCIS show morphological features of classic lobular neoplasia and lack E-cadherin expression, it is still unclear whether these lesions evolve through the same genetic pathway as lobular carcinomas or are high-grade ductal neoplasms that have lost E-cadherin. Here we have analysed a case of extensive PLCIS and invasive PLC associated with areas of E-cadherin-negative carcinoma in situ with indeterminate features, using immunohistochemistry, chromogenic in situ hybridization, high-resolution comparative genomic hybridization (CGH) and array-based CGH. We observed that all lesions lacked E-cadherin and ,-catenin and showed gain of 1q and loss of 16q, features that are typical of lobular carcinomas but are not seen in high-grade ductal lesions. In addition, amplifications of c-myc and HER2 were detected in the pleomorphic components, which may account for the high-grade features in this case and the reported aggressive clinical behaviour of these lesions. Taken together, these data suggest that at least some PLCs may evolve from the same precursor or through the same genetic pathway as classic lobular carcinomas. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] HER2 and tau expression as potential markers for response and survival to first line taxane plus cisplatin therapy in non-small cell lung cancerASIA-PACIFIC JOURNAL OF CLINICAL ONCOLOGY, Issue 4 2009Byoung Yong SHIM Abstract Aim: The aim of this study was to assess the role of various HER2, tau and bcl2 as prognostic markers of responsiveness to taxane and cisplatin therapy in patients with advanced NSCLC. Methods: Amplification of HER2 gene determined by chromogenic in situ hybridization (CISH) and HER2, tau and bcl2 protein expression determined by immunohistochemistry were assessed in 49 patients with NSCLC enrolled in our four clinical trials of taxane plus cisplatin chemotherapy. Results: The patients were classified as responders or non-responders, a negative tau expression was associated with a significantly higher rate of response compared to a positive tau expression (OR 3.33, 95% CI 1.01,10.97, P = 0.043). Patients with more than stable disease compared to those with progressive disease showed that negative amplification of the HER2 gene was associated with a significantly higher rate of disease control compared to positive amplification (OR 7.35, 95% CI 0.83,65.21, P = 0.048). Furthermore, HER2 gene amplification was strongly associated with the overall survival: 20 months (95% CI 9.007,30.993) in patients with negative amplification of the HER2 gene versus 12 months (95% CI 6.584,17.416) in patients with positive amplification of the HER2 gene (P = 0.040). A multivariate analysis with the Cox proportional hazards model confirmed that HER2 gene amplification was a significant independent prognostic factor with a hazard ratio of 2.334 (95% CI 1.060,5.142, P = 0.035). Conclusion: Tau protein expression and HER2 gene amplification are the prognostic factors in NSCLC patients treated with a taxane and cisplatin combination. [source] Human epidermal growth factor receptor 2 oncoprotein expression in breast cancer patients from central Anatolia, TurkeyASIA-PACIFIC JOURNAL OF CLINICAL ONCOLOGY, Issue 3 2009Hasan Senol COSKUN Abstract Aim: Human epidermal growth factor receptor 2 (HER2) overexpression is associated with poor prognosis and the frequency of HER2 positivity in breast cancer patients varies among different regions of the world. We studied HER2 expression in Turkish breast cancer patients. Methods: HER 2 expression was evaluated immunohistochemically in 107 breast cancer patients. HER2 expression was reported as negative or positive (3+) according to cellular membrane staining characteristics. The frequency of HER2 overexpression, distribution according to clinical characteristics, effect on survival and effect of chemotherapy on survival in relation to HER2 overexpression was evaluated. Results: The median age of patients was 49 years (range 27,76). HER2 was 3+ in 34 patients (31.8%). There was no significant difference in age, menopausal status, histopathology, lymph node involvement, stage and estrogen and/or progesterone receptor positivity in relation to HER2 expression. Forty-three patients (40.2%) relapsed and 21 patients (19.6%) died during the follow-up period. There was no significant difference in the relapse rate, distribution of relapse sites and death rate in relation to HER2 expression. The 3- and 5-year disease free survival rates were 67.1 and 40.5%, and the overall survival rates were 87.5 and 66.1%, respectively. Survival rate and calculated survival time were relatively shorter in HER2 3+ patients than in non-HER2 3+ patients, but these differences were not statistically significant. HER2 status did not affect survival period according to chemotherapy group. Conclusion: Immunohistochemistry findings of HER2 expression in Turkish breast cancer patients were similar to those found in the published reports. A shorter survival period was observed in HER2 3+ patients, but the difference was not statistically significant. [source] Clinical recommendations for the use of lapatinib ditosylate plus capecitabine for patients with advanced or metastatic HER2-positive breast cancerASIA-PACIFIC JOURNAL OF CLINICAL ONCOLOGY, Issue 1 2009Raymond D SNYDER Abstract Primary and acquired resistance to trastuzumab pose a therapeutic challenge when treating patients with HER2 (erbB-2)-positive locally advanced or metastatic breast cancer (MBC). The recent introduction of lapatinib (Tykerb/Tyverb, GlaxoSmithKline, Brentford, UK) provides a new management option for such patients. A prospective, randomized phase III clinical trial has confirmed that lapatinib in combination with capecitabine extends time to progressive disease in HER2-positive MBC, compared with capecitabine alone in patients with disease progression despite prior anthracycline, taxane and trastuzumab therapy. Preliminary data also indicate that lapatinib may exert a beneficial effect on brain metastases, a common sanctuary site for HER2-positive breast cancer following trastuzumab treatment. The tolerability of lapatinib is commensurate with that of other erbB family tyrosine kinase inhibitors and no significant new adverse events have emerged following its introduction into clinical practice. In particular, no additive cardiotoxicity has been observed when lapatinib is prescribed after trastuzumab therapy. Based on the published literature and supplemented by clinical experience, this article provides practical management recommendations for the use of lapatinib plus capecitabine in patients with MBC. Issues addressed include patient selection, baseline evaluation and monitoring for clinical benefit. The minimization and management of adverse events is also discussed in detail, particularly the dermatological and gastrointestinal effects, which are the most clinically significant side-effects of lapatinib therapy. Further recommendations cover the minimization of drug interactions, anticipated dosing alterations and the optimal employment of oral anticancer regimens. [source] Molecular characterization of upper urinary tract tumoursBJU INTERNATIONAL, Issue 6 2010Laura Izquierdo OBJECTIVES To assess gene-expression patterns of BIRC5, FGFR3, IGF2, KRT20, UPK2, EBF1, CDH1, FXYD3, HTERT, TP53, AGR2, HER2 and VEGF, widely known markers of bladder urothelial carcinoma (UC) in upper tract UC, and to determine their value as prognostic factors of tumour progression and cancer-specific survival. PATIENTS AND METHODS The study included 83 formalin-fixed paraffin-embedded tissue specimens (68 and 15 from patients with UTUC and controls, respectively) collected between 1990 and 2004. Thirteen bladder cancer-related genes were selected from previous reports and analysed by quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR) in all samples. RESULTS Six genes were over-expressed (BIRC5, FGFR3, KRT20, UPK2, FXYD3 and hTERT) and three under-expressed (AGR2, TP53 and VEGF) in the tumour group (P < 0.05). For four genes (IGF2, EBF1, CDH1 and HER2) there was no statistically significant difference between the tumour and control groups. Overall, 21 patients developed tumour progression and 13 died from UTUC after a mean follow-up of 35.24 months. The 5-year disease-free progression and cancer-specific survival rates were 65.8% and 72.9%, respectively. In a multivariate regression analysis, the independent predictive variable for tumour progression and cancer-specific survival was pathological stage (hazard ratio 3.60, P < 0.001; and 3.73, P < 0.005, respectively), but none of the studied genes were identified as prognostic factors of tumour progression or cancer-specific survival. CONCLUSIONS Our data suggest that bladder cancer and UTUC share some characteristics, but have differences in gene expression. None of BIRC5, FGFR3, IGF2, KRT20, UPK2, EBF1, CDH1, FXYD3, HTERT, TP53, AGR2, HER2 and VEGF were correlated either tumour progression or survival. [source] Analysis of HER2 expression in primary urinary bladder carcinoma and corresponding metastasesBJU INTERNATIONAL, Issue 7 2005Truls Gårdmark OBJECTIVE To evaluate the expression of HER2 receptors (previously reported to be over-expressed in malignant urothelium) in both primary tumours and metastases of transitional cell cancer, using two different staining methods and two different scoring techniques, considering the potential use of these receptors as targets for planned systemic anti-HER2 nuclide-based treatment. MATERIALS AND METHODS HER2 expression was evaluated with two different immunohistochemical methods in 90 patients with primary urinary bladder cancer tumours and corresponding metastases. Sections were first stained with the commercially available breast cancer test kit (HercepTest®, Dako, Glostrup, Denmark). Parallel sections were then stained with a modified HercepTest procedure. Two different evaluation criteria were compared; the HercepTest score that requires ,,10% stained tumour cells (as for breast cancer) and a proposed ,Target score' that requires >67% stained tumour cells. The latter score is assumed to be preferable for HER2-targeted radionuclide therapy. RESULTS Using the HercepTest kit, the Target score gave lower fractions of positive primary tumours and metastases than the HercepTest score. The modified HercepTest staining procedure and Target score gave high HER2 values in 80% of primary tumours and 62% of metastases, which is considerably more than that obtained with the HercepTest staining and score. There was a significant decrease in HER2 positivity with increasing distance from the primary tumour. In nine sentinel-node metastases assessed, all but one were HER2-positive. Considering all regional metastases, 74% were positive, and of distant metastases, 47%; 72% of the patients with positive primary tumours also expressed HER2 in their metastases. CONCLUSIONS When combining the modified HercepTest with customised evaluation criteria, more HER2-positive tumours were diagnosed. The degree of HER2 down-regulation was significantly higher in distant than in regional metastases. HER2-targeted therapy may be an alternative or complementary to other methods in the future treatment of metastatic urinary bladder carcinoma. [source] Breast cancer subtypes and response to systemic treatment after whole-brain radiotherapy in patients with brain metastasesCANCER, Issue 18 2010Anna Niwi, ska MD Abstract BACKGROUND: The aim of this study was to assess the role of systemic treatment after whole-brain radiotherapy (WBRT) in immunohistochemically defined biological subsets of breast cancer patients with brain metastases. METHODS: The group of 420 consecutive breast cancer patients with brain metastases treated at the same institution between the years of 2003 to 2009 was analyzed. Patients were divided into 4 immunohistochemically biological subsets, based on the levels of estrogen, progesterone, and human epidermal growth factor receptor 2 (HER2) receptors, and labeled as luminal A, luminal B, HER2, and triple-negative. Survival from brain metastases with and without systemic treatment after WBRT was calculated in 4 subsets. RESULTS: In the entire group, the median survival from brain metastases in patients without and with systemic treatment after WBRT was 3 and 10 months, respectively (P < .0001). In the triple-negative subset, the median survival from brain metastases with and without systemic treatment was 4 and 3 months (P = .16), and in the luminal A subset, it was 12 and 3 months, respectively (P = .003). In the luminal B subset, the median survival without further treatment, after chemotherapy and/or hormonal therapy, and after chemotherapy and/or hormonal therapy with targeted therapy was 2 months, 9 months, and 15 months, respectively (P < .0001). In the HER2 subset, the median survival was 4 months, 6 months, and 13 months, respectively (P < .0001). No significant response to systemic treatment was noted in the triple-negative breast cancer population. CONCLUSIONS: Systemic therapy, ordered after WBRT, appears to improve survival in patients with the luminal A, luminal B, and HER2 breast cancer subtypes. Targeted therapy was found to have an additional positive impact on survival. In patients with triple-negative breast cancer, the role of systemic treatment after WBRT appears to be less clear, and therefore this issue requires further investigation. Cancer 2010. © 2010 American Cancer Society. [source] | ||||||||||||||||||||||||||||