Showing papers on "HER2/neu published in 2005"
TL;DR: The role of c‐Met expression as a prognostic variable and consequently as an interesting target for novel therapeutic approaches deserves further analysis in a larger cohort of patients.
Abstract: Receptor tyrosine kinases play an important role in malignant transformation of epithelial cells by activating signal transduction pathways important for proliferation, invasion and metastasis. In a pilot study (n = 40), we evaluated expression of the c-Met and Her2/neu receptor tyrosine kinases and the c-Met ligand hepatocyte growth factor/scatter factor (HGF/SF) in primary breast cancers and their lymph node metastases using both conventional immunohistochemistry and confocal immunofluorescence. Neither c-Met and HGF/SF nor Her2/neu expression correlated with established prognostic factors such as age, lymph node involvement, estrogen receptor (ER), progesterone receptor (PR), tumor size, or grade. Both staining methods confirmed a significant correlation between c-Met overexpression and a high risk of disease progression. Furthermore, among tumors with c-Met overexpression, only 50% also overexpress Her2/neu, thus identifying a subset of patients with aggressive disease in addition to Her2/neu. Median disease-free survival in patients with c-Met overexpressing tumors was 8 months compared to 53 months when c-Met expression was low (p = 0.037; RR = 3.0). This significant impact of c-Met on tumor aggressiveness independent of Her2/neu was also confirmed by multivariate analysis. In conclusion, the role of c-Met expression as a prognostic variable and consequently as an interesting target for novel therapeutic approaches deserves further analysis in a larger cohort of patients.
259 citations
TL;DR: This HER2/neu (E75) vaccine is safe and effective in eliciting a peptide-specific immune response in vivo and seems to reduce the recurrence rate in patients with NPBC.
Abstract: Purpose E75 is an immunogenic peptide from the HER2/neu protein that is highly expressed in breast cancer. We are conducting a clinical trial of an E75 + granulocyte-macrophage colony-stimulating factor vaccine to assess safety, immunologic response, and the prevention of clinical recurrences in patients with disease-free, node-positive breast cancer (NPBC). Patients and Methods Fifty-three patients with NPBC were enrolled and HLA typed. HLA-A2+ patients (n = 24) were vaccinated, and HLA-A2− patients (n = 29) are observed prospectively as clinical controls. Local/systemic toxicities, immunologic responses, and time to recurrence are being measured. Results Only minor toxicities have occurred (one grade 3 [4%]). All patients have demonstrated clonal expansion of E75-specific CD8+T cells that lysed HER2/neu-expressing tumor cells. An optimal dosage and schedule have been established. Patients have developed delayed-type hypersensitivity reactions to E75 postvaccination compared with controls (33 v 7 mm; P <...
228 citations
TL;DR: The growth inhibitory effect of Herceptin on c-erbB2 overexpressing breast cancer cells is considerably modulated by EGFR coexpression and consequently EGFR/c-erb B2 homo- and heterointeractions, as well as the presence or absence of growth factors.
172 citations
TL;DR: Orlistat-induced FAS inhibition synergistically promoted apoptotic cell death when concurrently combined with trastuzumab as determined by an ELISA for histone-associated DNA fragments.
152 citations
TL;DR: Findings indicate that serum HER2/neu testing is clinically valuable in monitoring metastatic breast cancer patients undergoing trastuzumab-based treatment and provides additional value over the commonly used CA15-3 test.
Abstract: The purpose of this retrospective study was to determine the clinical utility of serum HER2/neu in monitoring metastatic breast cancer patients undergoing trastuzumab-based therapy and to compare these results with those obtained using cancer antigen (CA) 15-3. We also sought to determine whether early changes in serum HER2/neu concentrations could be a predictor of progression-free survival. Sera were obtained retrospectively from 103 women at four medical institutions. Patients eligible for participation were women with metastatic breast cancer who had HER2/neu tissue overexpression and were scheduled to be treated with trastuzumab with or without additional therapies as per the established practices of the treating physicians. A baseline serum sample for each patient was taken before trastuzumab-based therapy was started. Patients were subsequently monitored over 12 to 20 months and serum samples were taken at the time of clinical assessment and tested with Bayer's HER2/neu and CA15-3 assays. Concordance between clinical status in patients undergoing trastuzumab-based treatment and HER2/neu and CA15-3 used as single tests was 0.793 and 0.627, respectively, and increased to 0.829 when the tests were used in combination. Progression-free survival times did not differ significantly in patients with elevated baseline HER2/neu concentrations (≥ 15 ng/mL) and those with normal concentrations ( 77% or ≤ 77% of her baseline concentration. The median progression-free survival times for these two groups were 217 and 587 days, respectively. A similar trend was observed for a subcohort of patients treated specifically with a combination of trastuzumab and taxane. These findings indicate that serum HER2/neu testing is clinically valuable in monitoring metastatic breast cancer patients undergoing trastuzumab-based treatment and provides additional value over the commonly used CA15-3 test. The percentage of baseline HER2/neu concentrations in the early weeks after the start of therapy may be an early predictor of progression-free-survival.
152 citations
TL;DR: The data provide the first genetic evidence that Cox-2 contributes to HER2/neu-induced mammary tumorigenesis, which may help to explain the reduced risk of breast cancer associated with regular use of nonsteroidal anti-inflammatory drugs.
Abstract: The inducible prostaglandin synthase cyclooxygenase-2 (Cox-2) is overexpressed in ∼40% of human breast cancers and at higher frequencies in preinvasive ductal carcinoma in situ (DCIS). Cox-2 expression is particularly associated with overexpression of human epidermal growth factor receptor 2 (HER2/neu). To definitively interrogate the role of Cox-2 in mammary neoplasia, we have used a genetic approach, crossing Cox-2 -deficient mice with a HER2/neu transgenic strain, MMTV/NDL. At 20 weeks of age, mammary glands from virgin MMTV/NDL females contained multiple focal tumors, or mammary intraepithelial neoplasias, which histologically resembled human DCIS. Mammary tumor multiplicity and prostaglandin E 2 (PGE 2 ) levels were significantly decreased in Cox-2 heterozygous and knockout animals relative to Cox-2 wild-type controls. Notably, the proportion of larger tumors was decreased in Cox-2 -deficient mice. HER2/neu-induced mammary hyperplasia was also substantially reduced in Cox-2 null mice. Additionally, mammary glands from Cox-2 knockout mice exhibited a striking reduction in vascularization, and expression of proangiogenic genes was correspondingly reduced. Decreased vascularization was observed both in dysplastic and normal-appearing regions of Cox-2 -null mammary glands. Our data provide the first genetic evidence that Cox-2 contributes to HER2/neu-induced mammary tumorigenesis. This finding may help to explain the reduced risk of breast cancer associated with regular use of nonsteroidal anti-inflammatory drugs.
151 citations
TL;DR: In-trastuzumab Fab localized specifically in HER2/neu-positive BT-474 human breast cancer xenografts in athymic mice with tumor uptake of 7.7% injected dose (ID)/g and tumor/blood ratio of 25.2+/-1.6 at 72 h postinjection.
143 citations
TL;DR: Her2/neu overexpression was associated with an increased risk of progression and death, especially among women with FIGO Stage I and II ovarian carcinoma, and CA125 normalization at 3 and 6 months appeared a strong predictor of progressionand survival.
Abstract: Introduction: The HER2/neu proto-oncogene encodes a transmembrane receptor protein involved in the development and progression of the majority of cancers. Prior studies have shown t
141 citations
TL;DR: Overexpression of HER2/neu in uterine serous papillary endometrial cancer is an independent variable that is associated with poor outcome, occurs more frequently in black women, and may contribute to racial disparity in survival.
123 citations
TL;DR: The studies indicate that the anti-breast cancer properties of NDGA are related to the inhibition of two important RTKs, and agents of this class may provide new insights into potential therapies for this disease.
Abstract: Nordihydroguaiaretic acid (NDGA) is a phenolic compound isolated from the creosote bush Larrea divaricatta that has anti-cancer activities both in vitro and in vivo. We can now attribute certain of these anti-cancer properties in breast cancer cells to the ability of NDGA to directly inhibit the function of two receptor tyrosine kinases (RTKs), the insulin-like growth factor receptor (IGF-1R) and the c-erbB2/HER2/neu (HER2/neu) receptor. In MCF-7 human breast cancer cells, low micromolar concentrations of NDGA inhibited activation of the IGF-1R, and downstream phosphorylation of both the Akt/PKB serine kinase and the pro-apoptotic protein BAD. In mouse MCNeuA cells, NDGA also inhibited ligand independent phosphorylation of HER2/neu. To study whether this inhibitory effect in cells was due to a direct action on these receptors, we studied the IGF-1-stimulated tyrosine kinase activity of isolated IGF-1R, which was inhibited by NDGA at 10 μM or less. NDGA was also effective at inhibiting autophosphorylation of the isolated HER2/neu receptor at similar concentrations. In addition, NDGA inhibited IGF-1 specific growth of cultured breast cancer cells with an IC50 of approximately 30 μM. NDGA treatment (intraperitoneal injection 3 times per week) also decreased the activity of the IGF-1R and the HER2/neu receptor in MCNeuA cells implanted into mice. This inhibition of RTK activity was associated with decreased growth rates of MCNeuA cells in vivo. These studies indicate that the anti-breast cancer properties of NDGA are related to the inhibition of two important RTKs. Agents of this class may therefore provide new insights into potential therapies for this disease.
118 citations
TL;DR: Evidence suggests that a triple dose of the drug given once every three weeks has a pharmacokinetic profile expected to be equally efficacious, and the optimal schedule nor the optimal duration of trastuzumab therapy has yet been clearly defined in controlled clinical trials.
Abstract: Human epidermal growth factor receptor-2 (HER2/erbB-2) is a member of a family of four transmembrane receptor tyrosine kinases that regulate cell growth, survival and differentiation via multiple signal transduction pathways. Amplification of the HER2 gene occurs in 20-25% of human breast cancers. This amplification event is an independent adverse prognostic factor as well as a predictive factor for increased response to doxorubicin-based combination chemotherapy, response to trastuzumab and decreased response to hormonal therapy. Methods for detecting protein overexpression or gene amplification in clinical tumor specimens include immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) techniques, with the latter considered by some to be more accurate. Trastuzumab (Herceptin) is a recombinant humanized monoclonal antibody which targets an epitope in the extracellular domain of the HER2 protein. Preclinical models demonstrated that this antibody has significant anti-tumor activity as a single agent and has synergy with certain chemotherapeutic drugs. Phase II and III clinical trials performed in women with metastatic breast cancer that overexpress HER2 have shown that trastuzumab has clinical activity when used as first-, second- or third-line monotherapy, and improves survival when used as first-line therapy in combination with chemotherapy. Newer combinations with numerous chemotherapeutic drugs have also shown significant clinical activity in phase II studies. In all of these trials, trastuzumab was generally well-tolerated, but cardiac toxicity (particularly when the antibody was combined with anthracyclines) was an unexpected adverse effect. Although trastuzumab is currently usually administered on a weekly intravenous schedule, evidence suggests that a triple dose of the drug given once every three weeks has a pharmacokinetic profile expected to be equally efficacious. Neither the optimal schedule nor the optimal duration of trastuzumab therapy has yet been clearly defined in controlled clinical trials. Current clinical investigations of trastuzumab include its use in both the adjuvant and neoadjuvant settings as well as in combination with other chemotherapy drugs or new biologic targeted agents.
TL;DR: Although a rare breast cancer subtype, MBC is of considerable interest due to its pathological heterogeneity and differences in clinical behavior compared to typical breast carcinomas, and appears to rarely overexpress the HER2/neu oncoprotein.
Abstract: Background. Metaplastic breast carcinomas (MBC) are rare primary breast malignancies characterized by the co-existence of carcinoma with non-epithelial cellular elements. They can be classified as monophasic spindle cell (sarcomatoid) carcinoma, biphasic carcinosarcoma, adenocarcinoma with divergent stromal differentiation (osseous, chondroid and rarely rhabdoid) as well as adenosquamous and pure squamous cell carcinomas. There is a paucity of information on clinically relevant pathologic features and clinical outcomes for these rare tumors. The aim of this study was to review the pathologic features and clinical outcomes of all cases of MBC seen at a single institution between 1971 and 2000.
TL;DR: Treatment with apigenin induced apoptosis through cytochrome c release and caused a rapid induction of caspase‐3 activity and stimulated proteolytic cleavage of DFF‐45, and a structure–activity relationship study indicated that the position of B ring and the existence of the 3′, 4‐hydroxyl group on the 2‐phenyl group were important for the depletion of HER2/neu protein by flavonoids.
TL;DR: Chordomas, like many other solid-tissue tumors, express HER2/neu, EGFR, and the hepatocyte growth factor/scatter factor receptor c-Met, which represents a potentially viable experimental treatment option for refractory chordoma.
Abstract: Objective To examine the expression of c-Met, c-Erb-b2 (HER2/neu), and epidermal growth factor (EGFR) in a cohort of 12 chordomas, based on the current and future availability of targeted molecular inhibitors. Design Protein expression levels were analyzed by immunohistochemical analysis from archival tissue using multitumored tissue microarray and by Spearman rank correlation test. Setting Tertiary care facility. Subjects We assembled the cohort of 12 chordomas from patients treated at the Yale–New Haven Hospital from 1986 to 2003 and compared them with 51 other tumors from 17 assorted solid tissue tumor types along with 1 sample of healthy tissue from each site. Main Outcome Measure The expression of c-Met, HER2/neu, and EGFR. Results Most chordomas displayed strong expression of EGFR and c-Met, whereas a variable level of expression of HER2/neu was seen. In addition, we noted a strong correlation between EGFR and c-Met expression, especially for primary chordomas ( P = .006). Conclusions Chordomas, like many other solid-tissue tumors, express HER2/neu, EGFR, and the hepatocyte growth factor/scatter factor receptor c-Met. Most chordomas had strong expression of both the hepatocyte growth factor/scatter factor receptor and EGFR. Inhibitors to EGFR are already in clinical use for other solid-tissue tumors and represent a potentially viable experimental treatment option for refractory chordoma. Further studies are required to investigate these findings.
TL;DR: Prior screening and selection of appropriate immunohistochemistry-positive areas may be beneficial in the selection of some USPC patients undergoing FISH analysis for confirmation of gene amplification in USPC showing 2+ expression of HER2/neu.
TL;DR: The data suggest that high CXCR4 expression in breast cancer may be a potential marker in predicting isolated tumor cells in bone marrow and coexpression with EGFR/HER2-neu might further predict a particular subset of patients with high CK positivity inBone marrow.
Abstract: Interactions between the CXCR4 chemokine receptor in breast cancer cells and the ligand CXCL12/SDF-1α are thought to play an important role in breast cancer metastases. In this pilot study, CXCR4 expression along with other biomarkers including HER2-neu and EGFR, were measured in primary tumor samples of patients with operable breast cancer to test whether any of these biomarkers alone and in combination could indicate breast cancer with high likelihood of metastasizing to bone marrow. Cytokeratin (CK) positive cells in bone marrow were identified by flow-cytometry following enrichment with CK 7/8 antibody-coupled magnetic beads. Primary tumors (n = 18) were stained with specific antibodies for CXCR4, HER2-neu, EGFR, and PCNA using an indirect avidin–biotin horseradish peroxidase method. The majority of the patients had T2/T3 tumors (72%), or lymph node involvement (67%) as pathologic characteristics that were more indicative of high-risk breast cancer. High CXCR4 cytoplasmic expression was found in 7 of 18 patients (39%), whereas 6 of 18 patients (33%) were found to have CK positivity in bone marrow. The median number of CK+ cells was 236 (range, 20–847) per 5 × 104 enriched BM cells. The presence of CK+ cells in bone marrow was found to be associated with increased expression of CXCR4 alone or in addition to EGFR and/or HER2-neu expression (P = 0.013, P = 0.005, and P = 0.025, respectively) in primary tumors. Furthermore, three patients with high CK positivity (>236 CK+ per 5 × 104 enriched bone marrow cells) in bone marrow exclusively expressed high levels of CXCR4 with EGFR/HER2-neu (P = 0.001). Our data suggest that high CXCR4 expression in breast cancer may be a potential marker in predicting isolated tumor cells in bone marrow. CXCR4 coexpression with EGFR/HER2-neu might further predict a particular subset of patients with high CK positivity in bone marrow.
TL;DR: The data indicate that HER2/neu engages Akt to increase WT1 expression, and that WT1 protein plays a vital role in regulating cell cycle progression and apoptosis in HER2 /neu-overexpressing breast cancer cells.
Abstract: High levels of the Wilms' Tumor 1 (WT1) protein and mRNA had been associated with aggressive phenotypes of breast tumors. Here we report that the HER2/neu oncogene increases WT1 expression. Approximately threefold higher levels of WT1 protein were observed in MCF-7 breast cancer cells transfected with the HER2/neu oncogene than in parental MCF-7 cells. Conversely, inhibition of HER2/neu with the anti-HER2/neu trastuzumab (Herceptintrade mark) antibody decreased WT1 protein levels in HER2/neu-overexpressing BT-474 and SKBr3 cells. We also found that HER2/neu engages Akt to regulate WT1 levels since inhibition of Akt reduced WT1 levels. Decreased expression of WT1 protein led to cell cycle arrest at the G1 phase and increased apoptosis in HER2/neu-overexpressing cells, which is correlated with decreased cyclin D1 and Bcl-2 levels. Our data indicate that HER2/neu engages Akt to increase WT1 expression, and that WT1 protein plays a vital role in regulating cell cycle progression and apoptosis in HER2/neu-overexpressing breast cancer cells.
TL;DR: It is suggested that it is sufficient to analyze the prognostic factors from either the core biopsy prior to chemotherapy or the treated tumor sample instead of investigating both samples to markedly reduce the costs.
Abstract: The selection of a systemic breast cancer therapy is based on the expression pattern of immunohistochemical prognostic markers. In our study we sought to determine whether neoadjuvant chemotherapy may alter these expression patterns within the tumors. Our hypothesis was that the expression of the immunohistochemical prognostic markers does not differ between tissue specimens before and after neoadjuvant chemotherapy. We determined the protein expression levels of estrogen receptor, progesterone receptor, Ki67, p53 and HER2/neu in the core biopsy and the resected tumor sample from 25 patients receiving neoadjuvant chemotherapy. As a control group, we analyzed sample pairs from 30 patients who did not receive neoadjuvant chemotherapy. Additionally, we determined the relative HER2/neu gene copy number by FISH and/or real-time PCR. There were no significant differences in the changes in expression patterns from the core biopsy to the treated resected tumor between those who had received neoadjuvant chemotherapy and the control group. We suggest that it is sufficient to analyze the prognostic factors from either the core biopsy prior to chemotherapy or the treated tumor sample instead of investigating both samples. This would markedly reduce the costs.
TL;DR: It was postulated that HER2/neu over-expression and/or amplification might predispose to brain metastases, and the pathophysiology of this phenomenon and its clinical implications are discussed.
TL;DR: The ability of trastuzumab (Herceptin) Fab, labelled with 99mTc through introduced hydrazinenicotinamide (HYNIC) functionalities, to image HER2/neu-overexpressing human breast cancer xenografts in athymic mice was evaluated and preserved immunoreactivity towards SK-BR-3 cells was exhibited.
Abstract: ObjectiveTo evaluate the ability of trastuzumab (Herceptin) Fab, labelled with 99mTc through introduced hydrazinenicotinamide (HYNIC) functionalities, to image HER2/neu-overexpressing human breast cancer xenografts in athymic mice.MethodsFab fragments were produced by immobilized papain digestion of
TL;DR: A multiparametric fluorescent approach based on the simultaneous detection of HER2/neu gene amplification and protein expression was established to increase the accuracy, and to improve the reproducibility, of HercepTest diagnostics.
Abstract: The determination of HER2/neu status in breast carcinomas has become essential for the selection of breast cancer patients for Herceptin therapy. Herceptin treatment is used in patients with metastatic breast carcinoma with HER2/neu protein overexpression detected by immunohistochemistry (IHC) or gene amplification analysed by fluorescence in situ hybridization (FISH). A multiparametric fluorescent approach based on the simultaneous detection of HER2/neu gene amplification and protein expression was established to increase the accuracy, and to improve the reproducibility, of HER2/neu diagnostics. Based on four paraffin-embedded breast cancer cell lines, a combined fluorescent immunostaining (FIHC) and FISH method was developed by using the PathVysion HER2 DNA Probe Kit (VYSIS) and the polyclonal antibody from the HercepTest (DAKO). Diagnostic applicability was documented on 215 formalin-fixed primary breast carcinomas. Criteria for immunofluorescence quantification were chosen by analogy with the FDA-approved HercepTest scoring, ranging from 0 to 3+. There was 97.7% concordance between conventional IHC and fluorescence IHC. The FISH data resulting from the multiparametric approach did not differ from conventional FISH. Breast carcinomas with HER2/neu protein overexpression and simultaneous gene amplification were detected with 100% sensitivity. In addition, five of the 215 cases (2.3%) had HER2/neu gene amplification without protein overexpression. The main advantage of this novel approach is that polysomy, aneuploidy, gene amplification, and protein content can be analysed simultaneously in the same cell.
TL;DR: The frequent elevation of PTK6 expression, and its correlation with Her2/neu oncogene over‐expression, suggests a clinically relevant link between these two over‐expressed tyrosine kinases.
Abstract: Expression of eight tumour-relevant genes was studied in formalin-fixed, paraffin-embedded tissue from 54 invasive ductal breast carcinomas using quantitative reverse transcription PCR (Q-RT-PCR). Seven of the genes map to chromosome 20q and are potential candidates for gene amplification and over-expression. The Her2/neu oncogene, on chromosome 17q, was investigated in the same tumours. Increased expression was most frequent for PTK6, Her2/neu, and ADA. No other 20q candidate gene (AIB1, PTPN1, ZNF217, and PFDN4) was prominent. A significant correlation between the expression of the tyrosine kinases PTK6 and Her2/neu was detected. The frequent elevation of PTK6 expression (in 43/54 tumours), and its correlation with Her2/neu oncogene over-expression, suggests a clinically relevant link between these two over-expressed tyrosine kinases.
TL;DR: The findings indicate that the association between ER, PR and HER2/neu overexpression varies with age, and the hormone receptors are not an independent predictor for the HER2-neu status in young women while they are in elder patients.
TL;DR: Combined treatment with Her2/neu and Cox-2 inhibitors may be beneficial for the subgroup of Her2-neu- andcox-2-expressing tumours and will have to be assessed in further preclinical and clinical studies.
Abstract: We examined the expression of Her2/neu and Cox-2 in bladder cancer and its relationship to clinicopathological factors, survival data and patient outcome. From 153 consecutive patients who had undergone radical cystectomy for bladder cancer, tumour tissue was analysed for Her2/neu amplification by fluorescent in situ hybridisation and for Her2/neu and Cox-2 protein expression by immunohistochemistry. Results were correlated with clinical data and survival times. Cox-2 and Her2/neu co-expression was present in 44 (33%) of 132 transitional cell carcinomas. Although this association was significant (p = 0.003), there was no significant association between Cox-2 and Her2/neu amplification status. Each marker was independent of primary tumour stage and lymph node status, as well as histological grading. However, the co-existence of Her2/neu amplification and Cox-2 expression correlated with distant metastases: of 5 Cox-2-positive samples, 2 (40%) showed Her2/neu amplification. This was only a trend, amounting to no more than borderline statistical significance (p = 0.046). Kaplan-Meier survival analysis did not demonstrate any relationship between Cox-2 or Her2/neu expression or amplification alone or in combination with respect to overall and disease-free survival. Analysing the co-expression of Cox-2 and Her2/neu status does not add any prognostic information in patients with bladder cancer. Nevertheless, combined treatment with Her2/neu and Cox-2 inhibitors may be beneficial for the subgroup of Her2/neu- and Cox-2-expressing tumours and will have to be assessed in further preclinical and clinical studies.
TL;DR: Smad7 appears to be upregulated in endometrial cancers compared to normal endometrium, and high Smad7 gene expression was associated with a shorter time to recurrence, which is consistent with a reduction in tumor surveillance and potential cancer formation.
TL;DR: This study validated the use of the novel CD107 cytotoxicity assay in the detection of influenza and HER2/neu tumor-specific cytolytic CD8+ T cells and suggested its usefulness for monitoring cancer trials.
Abstract: The recently reported FACS-based CD107 assay has been used in human HIV and CMV antigen models as well as in the ex vivo analysis of tumor cytolytic T cells in a melanoma model by a single group. The purpose of our study was to validate this assay and to use it in previously untested viral and tumor antigen models. Specifically, we investigated the use of the novel CD107 cytotoxicity assay in the detection of influenza and HER2/neu tumor-specific cytolytic CD8+ T cells. CD8+ T cells from HLA-A2+ healthy donors were stimulated with autologous dendritic cells pulsed with FluM or the HER2/neu peptides, E75 or GP2. These CD8+ T cells were then tested in cytotoxicity assays at varying effector:target (E:T) ratios against T2 targets. Cytotoxicity was measured by detection of CD107a and b on the surface of CD8+ T cells. An E:T of 1:5 was found to optimize the resulting percentage of CD8+CD107+ T cells. E75- and GP2-stimulated CD8+ T cells were then tested in cytotoxicity assays with MCF-7 (HER2/neu+HLA-A2+) and AU565 (HER2/neu+HLA-A2-) tumor cells. Cytotoxicity was measured by both the CD107 assay and the 51Cr release assay. Results of cytotoxicity were then correlated between these two assays. In representative experiments, the CD107 assay identified average specific increases for E75- and GP2-stimulated cells of 4.26 and 3.57%, respectively. These results correlated favorably with cytotoxicity as measured by the traditional 51Cr assay. These findings confirm preliminary reports of the CD107 assay and suggest its usefulness for monitoring cancer trials.
TL;DR: Vaccination of mice with a plasmid gene vaccine and an adenovirus gene vaccine, each containing the gene for HER2/neu, prevented growth of a HER2 /neu-expressing breast cancer cell line injected into the mammary fat pad or intravenously.
Abstract: Once metastasis has occurred, the possibility of completely curing breast cancer is unlikely, particularly for the 30 to 40% of cancers overexpressing the gene for HER2/neu. A vaccine targeting p185, the protein product of the HER2/neu gene, could have therapeutic application by controlling the growth and metastasis of highly aggressive HER2/neu+ cells. The purpose of this study was to determine the effectiveness of two gene vaccines targeting HER2/neu in preventive and therapeutic tumor models. The mouse breast cancer cell line A2L2, which expresses the gene for rat HER2/neu and hence p185, was injected into the mammary fat pad of mice as a model of solid tumor growth or was injected intravenously as a model of lung metastasis. SINCP-neu, a plasmid containing Sindbis virus genes and the gene for rat HER2/neu, and Adeno-neu, an E1,E2a-deleted adenovirus also containing the gene for rat HER2/neu, were tested as preventive and therapeutic vaccines. Vaccination with SINCP-neu or Adeno-neu before tumor challenge with A2L2 cells significantly inhibited the growth of the cells injected into the mammary fat or intravenously. Vaccination 2 days after tumor challenge with either vaccine was ineffective in both tumor models. However, therapeutic vaccination in a prime–boost protocol with SINCP-neu followed by Adeno-neu significantly prolonged the overall survival rate of mice injected intravenously with the tumor cells. Naive mice vaccinated using the same prime–boost protocol demonstrated a strong serum immunoglobulin G response and p185-specific cellular immunity, as shown by the results of ELISPOT (enzyme-linked immunospot) analysis for IFNγ. We report herein that vaccination of mice with a plasmid gene vaccine and an adenovirus gene vaccine, each containing the gene for HER2/neu, prevented growth of a HER2/neu-expressing breast cancer cell line injected into the mammary fat pad or intravenously. Sequential administration of the vaccines in a prime–boost protocol was therapeutically effective when tumor cells were injected intravenously before the vaccination. The vaccines induced high levels of both cellular and humoral immunity as determined by in vitro assessment. These findings indicate that clinical evaluation of these vaccines, particularly when used sequentially in a prime–boost protocol, is justified.
TL;DR: Increased serum Her-2/neu correlates with the presence of metastatic disease and it may indicate an increased risk of death in patients with castrate, metastatic prostate cancer.
TL;DR: It is hypothesized that the human epithelial growth factor receptor 2 (C‐erb‐B2, also termed HER2/neu) may contribute to the tumor phenotype and provide a new therapeutic target for this soft tissue tumor.
Abstract: Background. Synovial sarcoma is a malignant mesenchymal tumor composed of varying proportions of spindle and epithelial cell components. Because of the histologic and immunohistochemical similarity of synovial sarcoma to epithelial carcinomas, we hypothesized that the human epithelial growth factor receptor 2 (C-erb-B2, also termed HER2/neu) may con- tribute to the tumor phenotype and provide a new therapeutic target for this soft tissue tumor. Methods. Three head and neck, one chest wall, and seven extremity synovial sarcomas were evaluated for C-erb-B2 (HER2/ neu) expression by immunohistochemistry, Western immuno- blotting, and fluorescence in situ hybridization (FISH). Results. The head and neck cases demonstrated immuno- histochemically strong positive staining, whereas tumors from other anatomic locations showed neither positive nor cyto- plasmic restricted staining. Antigen-targeted antibody therapy (trastuzumab) was initiated in two patients. Conclusions. These results demonstrate that C-erb-B2 (HER2/neu) may play a role in the tumorigenesis of synovial sarcoma; and, therefore, antigrowth factor therapies may pro- vide a previously unrecognized pharmaceutical approach to soft tissue tumors. The data also suggest that although syno- vial sarcoma of the head and neck and synovial sarcoma of the extremities have similar morphologic features, they may be clinically and mechanistically distinct entities. A 2005 Wiley Periodicals, Inc. Head Neck 27: 883-892, 2005
TL;DR: The quantitative assessment of HER2/neu expression in malignant tumors aided by other proliferation markers such as SPF, DI, and ploidy could be useful in selecting patients for more aggressive treatment or for predicting outcome.