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HER-2/neu Overexpression (her-2/neu + overexpression)
Selected AbstractsChromogenic in situ hybridization analysis of HER-2/neu status in breast carcinoma: Application in screening of patients for trastuzumab (Herceptin®) therapyPATHOLOGY INTERNATIONAL, Issue 8 2001Hiroyuki Kumamoto Evaluation of HER-2/neu status is important in the management of patients with breast carcinoma, especially in determining the possible application of trastuzumab, a humanized anti-HER-2/neu monoclonal antibody. Chromogenic in situ hybridization (CISH) detection of the HER-2/neu oncogene is a newly developed in situ hybridization method that utilizes a robust and unique-sequence DNA probe labeled with digoxygenin, and sequential incubations with antidigoxygenin fluorescein, antifluorescein peroxidase, and diaminobenzidine. In this study, we examined 20 archival specimens of human breast carcinoma using CISH, and we correlated findings with immunohistochemical findings for HER-2/neu. HER-2/neu immunohistochemistry was carried out with HercepTestTM, a standardized immunohistochemical examination system for HER-2/neu overexpression in surgical pathology specimens. CISH analysis could be done in 18 out of 20 cases examined. Gene copy signals for HER-2/neu were recognized as intranuclear brown dots in both neoplastic and non-neoplastic cells. Seven carcinomas showed an increased number or size of signals and were interpreted as being positive for HER-2/neu amplification. Eight cases were positive with the HercepTestTM. Seven out of eight carcinoma cases found to overexpress immunoreactive HER-2/neu also demonstrated HER-2/neu gene amplification following CISH analysis. There was a significant correlation between immunohistochemical and CISH analyses (P< 0.001). We found that CISH was a specific, sensitive and easily applicable method for the detection of HER-2/neu gene amplification, which may be used together with immunohistochemical examination for the evaluation of patients with breast carcinoma. [source] Role of coordinated molecular alterations in the development of androgen-independent prostate cancer: an in vitro model that corroborates clinical observationsBJU INTERNATIONAL, Issue 1 2006YAN SHI OBJECTIVE To investigate the role of potential downstream targets of HER-2/neu, including the cell-cycle regulator p27, proliferation-associated protein Ki-67, apoptosis inhibitor Bcl-2, and signal-transduction molecule Akt (which is associated with cell survival), as the development of androgen-independent prostate cancer (AIPC) in patients who are initially responsive to androgen-ablation therapy (AAT) is a significant clinical problem. PATIENTS AND METHODS Earlier studies showed that high levels of HER-2/neu tyrosine kinase receptor expression as assessed by immunohistochemistry were significantly associated with the development of AIPC, and we hypothesised that HER-2/neu overexpression provides an alternative proliferative stimulus upon androgen depletion. We established a unique clinical model system, comprising patients who received no AAT, or who had preoperative AAT, or those with advanced tumours resistant to AAT. To test our hypothesis in vitro, we stably transfected full-length HER-2/neu cDNA in androgen-responsive LNCaP cells and examined the effects of HER-2/neu overexpression on cell proliferation, apoptosis, androgen-receptor activation, and Akt phosphorylation upon androgen deprivation by using immunohistochemistry and Western blot technique. RESULTS p27 expression was initially induced on exposure to AAT, and significantly decreased in AIPC (P < 0.001). There was also a significant increase in the Ki-67 index in AIPC (P = 0.001). Elevated Bcl-2 expression was closely associated with AAT (P = 0.002), suggesting that Bcl-2 expression is induced on initial exposure to AAT. Further, Bcl-2 expression was highest in hormone-resistant cancers (P < 0.001). Using the HER-2/neu transfected cell-line model, we confirmed the mechanistic basis of the clinical observations which elucidate the pathway leading to HER-2/neu-mediated androgen independence. On androgen deprivation, the HER-2/neu transfected cells had higher proliferation rates, lower G1 arrest, inhibited p27 up-regulation, a lower apoptotic index, and higher Bcl-2, prostate-specific antigen and phosphorylated Akt expression than the mock-transfected LNCaP cells. CONCLUSION This study suggests that prostate cancer cells undergo a series of coordinated changes after exposure to AAT, which eventually result in the development of androgen independence. Further, in support of previous results, it appears that a major factor in this process is the induction of HER-2/neu overexpression, which occurs after initial exposure to AAT. HER-2/neu may contribute to the development of androgen independence through: (i) maintaining cell proliferation; (ii) inhibiting apoptosis; and/or (iii) inducing AR activation in a ligand-independent fashion. These effects may be mediated, at least in part, through activation of the PI3K/Akt pathway. [source] Evaluation of HER-2/neu expression in prostatic adenocarcinomaCANCER, Issue 8 2002A request for a standardized, organ specific methodology Abstract BACKGROUND Some evidence suggests a role for HER-2/neu overexpression in prostate carcinoma progression. Reported rates of HER-2/neu overexpression in patients with prostate carcinoma vary greatly. METHODS The authors studied radical prostatectomy specimens from 38 patients who had biochemical failure after undergoing radical prostatectomy for prostate carcinoma. Immunohistochemistry for HER-2/neu overexpression using the HercepTest kit (Dako Corporation, Carpenteria, CA) was employed. Two different antigen-retrieval techniques were used: 1) the standard U.S. Food and Drug Administration (FDA)-approved HercepTest assay and 2) a modified HercepTest, which employed an alkaline citrate buffer, pH 9.0, for antigen retrieval and a 1-hour primary antibody incubation time. The level of HER-2/neu expression was evaluated on a scale from 0 (no staining) to 3+ according to the published guidelines. Fluorescent in situ hybridization for gene amplification was performed on all specimens. RESULTS With the standard technique, only one specimen had 2+ staining, and no specimens had 3+ staining. With the modified technique, 10 specimens (26%) had 2+ staining, and 9 specimens (24%) had 3+ staining. There was a significant association between the level of HER-2/neu expression shown with the modified technique and tumor stage (P = 0.03) as well as Gleason grade (P = 0.01). None of the specimens had HER-2/neu gene amplification. CONCLUSIONS The authors report a simple modification of the HercepTest that resulted in an increased rate of HER-2/neu expression, which was correlated with poor-risk pathologic findings. The findings suggest that adenocarcinoma of the prostate should be evaluated for HER-2/neu expression with a prostate specific immunohistochemical procedure that differs from the FDA-approved standard procedure. Cancer 2002;95:1650,5. © 2002 American Cancer Society. DOI 10.1002/cncr.10839 [source] HER-2/neu overexpression in patients with radically resected nonsmall cell lung carcinomaCANCER, Issue 10 2002Impact on long-term survival Abstract BACKGROUND Using immunohistochemistry, the authors prospectively investigated the expression of HER-2/neu protein in radically resected specimens of nonsmall cell lung carcinoma (NSCLC) and evaluated its impact on long-term prognosis. METHODS Between January 1991 and February 1992, surgical specimens from 130 consecutive patients who underwent radical resection for NSCLC (60 squamous cell carcinoma, 48 adenocarcinoma cases, and 22 large cell carcinomas) and that were staged (according to the TNM staging system) pathologically as Stage I (41 cases [ 32%]), Stage II (37 cases [28%]), and Stage IIIA (52 cases [40%]) were investigated for the expression of HER-2/neu using an avidin-biotin complex immunohistochemical technique. A semiquantitative four-stage grading system was used (0%, 1,5%, 6,20%, and > 20% positive cells) and an average number of 1500 cells/section was considered. Data were correlated with clinical and pathologic variables. RESULTS Normal bronchial tissue was found to be completely negative for HER-2/ neu expression whereas 21 of the 130 tumor specimens (16%) were positive (range 1,> 20%). HER-2/neu positivity did not appear to differ significantly among pathologic stages and histotypes. Using a predetermined cutoff value of 5% positive cells, 15 tumor specimens (12%) were found to be above this value. The median survival time (85 weeks vs. 179 weeks) and overall survival rate were significantly lower in patients with > 5% HER-2/neu -positive tumors (hazard ratio for the group with > 5% positive cells: 2.94, 95% confidence interval, 1.62,5.34; P < 0.0004). On multivariate analysis, HER-2/ neu and extent of tumor emerged as independent factors for disease-related mortality. CONCLUSIONS In NSCLC, the negative impact of HER-2/neu overexpression on survival was maintained in the long-term follow-up of radically resected patients. HER-2/neu overexpression may be a valuable prognostic factor as well as a potential target for biologic therapies. Cancer 2002;94:2669,74. © 2002 American Cancer Society. DOI 10.1002/cncr.10531 [source] Her-2/neu and EGFR tyrosine kinase activation predict the efficacy of trastuzumab-based therapy in patients with metastatic breast cancerINTERNATIONAL JOURNAL OF CANCER, Issue 5 2006Gernot Hudelist Abstract Her-2/neu overexpression in human breast cancer leads to an aggressive biological behavior and poor prognosis. Although the anti-Her-2/neu antibody trastuzumab (Herceptin®) has become a valuable therapeutic option for patients with Her-2/neu -overexpressing breast cancer, many patients do not benefit from this therapy. To evaluate the effect of receptor activation on tumor response, we have investigated the phosphorylation status of Her-2/neu and EGFR in 46 Her-2/neu -overexpressing tumor samples from trastuzumab-treated metastatic breast cancer patients by immunohistochemistry. Activated (p)tyr-1248 Her-2/neu was detected in 9 of 46 breast cancers (20%), and activated (p)tyr-845 and (p)tyr-1173 EGFR were both present in 6 tumors (13%) while EGFR was present in 16 cases (35%). ptyr-1248 Her-2/neu showed a trend to correlate with increased response to trastuzumab (p = 0.063), while ptyr-845, ptyr-1173 EGFR and EGFR did not. The presence of ptyr-1248 Her-2/neu and ptyr-845 or ptyr-1173 EGFR, however, was a strong predictor of both response to trastuzumab-based treatment (OR = 8.0, p = 0.021 and OR = 8.0, p = 0.021) and clinical benefit (OR = 5.47, p = 0.041 and OR = 6.22, p = 0.028 multivariate logistic regression analysis). Furthermore, ptyr-845 EGFR and ptyr-1248 Her-2/neu were both independent predictors of progression-free survival (RR = 0.21, p = 0.01 and RR = 0.45, p = 0.026, multivariate analysis). Patients with ptyr-845 EGFR positive tumors also tended toward increased overall survival (RR = 0.17, p = 0.082). Taken together, we have demonstrated that the determination of activated EGFR improves the utility of ptyr-1248 Her-2/neu staining in predicting the clinical outcome of patients undergoing trastuzumab treatment. We hypothesize that the activation state of both Her-2/neu and EGFR are key determinants for trastuzumab efficacy. © 2005 Wiley-Liss, Inc. [source] HER-2/neu expression in extramammary Paget disease: a clinicopathologic and immunohistochemistry study of 47 cases with and without underlying malignancyJOURNAL OF CUTANEOUS PATHOLOGY, Issue 7 2009Jose A. Plaza Extramammary Paget disease (EMPD) is an infrequent skin cancer sometimes representing a secondary event caused by extension of an underlying carcinoma. Her-2/neu overexpression in breast cancer is correlated with a more aggressive behavior, but anti-Her-2/neu therapy improves survival in these patients. We investigated Her-2/neu expression by immunohistochemistry in cases of EMPD with and without underlying malignancy to try to correlate with tumor recurrence, progression and possible targeted therapy. Forty-seven cases were analyzed (6 from the scrotum, 7 perianal region, 1 axilla and 33 vulva). Two cases had invasive EMPD (one from vulva and one from scrotum). The overall Her-2/neu expression was 31.9%. Of the noninvasive EMPD of the vulva (32 cases), Her-2/neu was shown in 38%. The case of invasive vulvar EMPD was negative. All six scrotal EMPD lacked Her2/neu expression. Her-2/neu was expressed in two of seven perianal cases (33.3%). The EMPD on the axilla (one case) was negative. Eighteen cases had recurrence, and of these, 44.4% expressed Her-2/neu in the initial lesion. A high proportion of EMPD showed Her-2/neu expression (31.9%), indicating that these patients may benefit from targeted therapy. The proportion of positive cases was higher in lesions that had recurred at last follow up (44.4%), suggesting a more aggressive behavior. [source] Tubular carcinoma and grade 1 (well-differentiated) invasive ductal carcinoma: Comparison of flat epithelial atypia and other intra-epithelial lesionsPATHOLOGY INTERNATIONAL, Issue 10 2008Lakshmi P. Kunju The distinction between tubular carcinomas (TC) and invasive well-differentiated (grade 1) ductal carcinoma (IDC) is important given treatment and prognostic differences. Studies have described a strong association between flat epithelial atypia (FEA) and TC. The incidence of FEA associated with grade 1 IDC is not well established. The aim of the present study was to assess morphology and intra-epithelial lesions between 14 TC and 18 grade 1 IDC matched for size. Of 14 TC, eight (57%) had associated FEA, seven (50%) had micropapillary atypical ductal hyperplasia (ADH), three (21%) had low nuclear grade ductal carcinoma in situ (DCIS), and four (29%) had lobular neoplasia. Notably, only two of 18 (11%) grade 1 IDC had associated FEA. Three of 18 (16%) grade 1 IDC had ADH, two (11%) had lobular neoplasia, and seven (39%) had DCIS. All tubular carcinomas were estrogen receptor (ER) positive and negative for Her-2/neu overexpression. All grade 1 IDC were ER positive but 5% also overexpressed Her-2/neu. Axillary lymph node metastasis was present in 11% of grade 1 IDC and absent in TC. A strong association was found between TC, FEA, and micropapillary ADH, which may reflect a biological progression. Despite matching for tumor size, grade 1 IDC have a higher incidence of lymph node metastasis and may have Her-2-neu overexpression compared to TC. [source] | ||||||||||