Human Epidermal Growth Factor Receptor-2 Protein Research Articles

Abstract P4-07-10: Gene expression profiling in immunophenotypic triple negative breast carcinomas harboring HER-2 amplification identifies tumors with distinct molecular signatures and increased ERBB2 gene expression

Abstract Introduction: Breast carcinomas can be classified by hormone receptors and human epidermal growth factor receptor-2 (HER-2) status. HER-2 status is assessed using immunohistochemistry (IHC) and/or fluorescent in situ hybridization (FISH). Immunophenotypic triple negative breast cancers (iTNBC) may harbor an amplification of HER-2 detected by FISH (iTNBC-FISHAmp) or may be negative by FISH (iTNBC-FISHNeg). The discrepancy between protein expression and gene amplification in these tumors poses relevant questions on tumor biology and for treatment implications. Here we investigate iTNBC-FISHAmp and iTNBC-FISHNeg by gene expression profile. Methods: A total of 40 iTNBC were selected. HER-2 IHC scores (0 or 1+) were annotated. All the tumors were tested by FISH showing 20 iTNBC-FISHAmp and 20 iTNBC-FISHNeg. The tumor morphology was reviewed by 2 pathologists, and stromal tumor infiltrating lymphocytes (sTILs) were estimated as high (H-sTILs) or low (L-sTILs). The areas of tumor with best cellularity were selected for RNA extraction. Gene expression profiling using a panel of 776 genes across 33 biological signatures was performed using Nanostring technology. Results: ERBB2 gene expression was significantly higher in iTNBC-FISHAmp when compared to iTNBC-FISHNeg tumors (p<0.001). ERBB2 gene expression was significantly higher in tumors with IHC 1+ when compared to tumors with IHC 0 (p<0.001). Genes related to the biologic stromal signature showed a lower expression in iTNBC-FISHAmp when compared with iTNBC-FISHNeg (p=0.015). All tumors were classified as basal-like molecular subtype. The histologic presence of sTILs had no correlation with ERBB2 gene expression. Tumors with H-sTILs significantly correlated with the multiple biological signatures related to inflammation and immunoresponse, including PDL1, PD1, TIGIT, CD8, Cytotoxic cells, TREG (regulatory T cell), TIS (tumor inflammatory signature); while tumors with L-sTILs significantly correlated with B7-H3, stromal, AR, and claudin-low signatures. Conclusions: Our results demonstrate that iTNBC tumors are a heterogeneous entity at the molecular level. In iTNBC-FISHAmp, ERBB2 gene is significantly up-regulated despite low HER-2 protein expression. Tumors with HER-2 IHC 1+ are associated with higher gene expression than tumors with IHC 0. iTNBC-FISHAmp show a lower expression of genes related to biologic stoma signature with possible implications on biology of tumor microenvironment. The histological assessment of sTILs in iTNBC correlates with multiple gene expression signatures that are closely related to tumor immunogenicity and sensitivity to immunotherapy. Further studies are needed to establish the functional role of HER-2 signaling in these tumors. Citation Format: Paolo Cotzia, Theodore Vougiouklakis, Ursula Andreo, George Jour, Christopher Schwartz, Maryann Kwa, Sylvia Adams, Francisco Esteva, Deborah Axelrod, Freya Schnabel, Matija Snuderl, Farbod Darvishian. Gene expression profiling in immunophenotypic triple negative breast carcinomas harboring HER-2 amplification identifies tumors with distinct molecular signatures and increased ERBB2 gene expression [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-07-10.

In vivo studies of a peptidomimetic that targets EGFR dimerization in NSCLC.

Studies related to lung cancer have shown a link between human epidermal growth factor receptor-2 (HER2) expression and poor prognosis in patients with non-small cell lung cancer (NSCLC). HER2 overexpression has been observed in 3-38% of NSCLC, while strong HER2 protein overexpression is found in 2.5% of NSCLC. However, HER2 dimerization is important in lung cancer, including EGFR mutated NSCLC. Since HER2 dimerization leads to cell proliferation, targeting the dimerization of HER2 will have a significant impact on cancer therapies. A peptidomimetic has been designed that can be used as a therapeutic agent for a subset of NSCLC patients overexpressing HER2 or possessing HER2 as well as EGFR mutation. A cyclic peptidomimetic (18) has been designed to inhibit protein-protein interactions of HER2 with its dimerization partners EGFR and HER3. Compound 18 exhibited antiproliferative activity in HER2-positive NSCLC cell lines at nanomolar concentrations. Western blot analysis showed that 18 inhibited phosphorylation of HER2 and Akt in vitro and in vivo. Stability studies of 18 at various temperature and pH (pH 1 and pH 7.6), and in the presence of liver microsomes indicated that 18 was stable against thermal and chemical degradation. Pharmacokinetic parameters were evaluated in nude mice by administrating single doses of 4 mg/kg and 6 mg/kg of 18 via IV. The anticancer activity of 18 was evaluated using an experimental metastasis lung cancer model in mice. Compound 18 suppressed the tumor growth in mice when compared to control. A proximity ligation assay further proved that 18 inhibits HER2:HER3 and EGFR: HER2 dimerization. Overall, these results suggest that 18 can be a potential treatment for HER2-dimerization related NSCLC.

Expression of CD147, MMP-9 and HER-2 in patients with gastric cancer and their correlation with clinicopathology and prognosis

Objective To investigate the correlation between the expression of extracellular matrix metalloproteinase-inducible factor (CD147), matrix metalloproteinase-9 (MMP-9) and human epidermal growth factor receptor-2 (HER-2) in gastric cancer tissues and clinical pathology and prognosis. Methods From June 2016 to June 2018, 80 gastric cancer specimens from the First People's Hospital of Taizhou were collected as observation group, and another 60 normal specimens of gastric mucosa adjacent to cancer were selected as control group.The expressions of CD147, MMP-9 and HER-2 were detected by SP immunohistochemical method.The positive rates of CD147, MMP-9 and HER-2 protein expression, the positive rates of CD147, MMP-9 and HER-2 protein expression in different pathological characteristics, and the positive rates of CD147, MMP-9 and HER-2 protein expression in different prognosis were compared between the two groups. Results The positive rates of CD147 (73.75%), MMP-9 (76.25%) and HER-2 (42.50%) in the observation group were higher than those in the control group (21.67%, 25.00%, 5.00%), the differences were statistically significant (χ2=37.233, 36.288, 24.797, all P 0.05). The positive rates of CD147 (93.88%), MMP-9 (95.92%) and HER-2 (61.22%) with lymph node metastasis were higher than those without lymph node metastasis (41.94%, 45.16%, 12.90%), the differences were statistically significant (χ2=26.462, 27.012, 18.142, all P<0.05). The positive rates of CD147 (96.15%), MMP-9 (92.31%) and HER-2 (69.23%) in the death group were higher than those in the survival group (62.96%, 68.52%, 29.63%), the differences were statistically significant(χ2=9.987, 5.484, 11.263, all P<0.05). Conclusion High expression of CD147, MMP-9 and HER-2 proteins in gastric cancer tissues is closely related to invasion and metastasis, which can become a new prognostic marker and therapeutic target of gastric cancer. Key words: Gastric cancer; Paracancerous tissue of gastric mucosa; Extracellular matrix metalloproteinase-inducing factor; Matrix metalloproteinase-9; Human epidermal growth factor receptor-2; Tumor diameter; Differentiation degree; Lymph node metastasis; Prognosis

Impact of HER2 aberrations on EGFR-TKI treatment outcomes in lung tumors harboring EGFR mutations: A HER2-CS STUDY subset analysis.

9056 Background: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are a key treatment for EGFR-mutated non-small-cell lung carcinoma (NSCLC). To date, a biomarker to predict whether NSCLC will exhibit a short- or long-term response to first- or second-generation EGFR-TKIs has not been established for clinical use. Human epidermal growth factor receptor-2 (HER2) aberrations are mechanisms for acquired resistance to EGFR-TKIs; however, their impact on EGFR-TKI therapy outcomes in EGFR-mutant NSCLC has not yet been systematically evaluated. Methods: Patients with advanced NSCLC were prospectively registered from more than 35 institutes (HER2-CS STUDY UMIN 000017003). EGFR mutations or anaplastic lymphoma kinase gene translocations were assessed at each institution using a commercially approved test. HER2 protein expression levels were determined by immunohistochemistry (IHC) using the Ventana I-VIEW PATHWAY anti-HER-2/neu (4B5). The IHC status scoring system applied to gastric cancer was used. Results: Of 1,126 screened patients with NSCLC, 354 (31.8%) had EGFR-mutated tumors, and the HER2 protein statuses were as follows: IHC0 (n = 71, 26%), IHC1+ (n = 148, 53%), IHC2+ (n = 51, 18%), and IHC3+ (n = 7, 3%). The patients’ demographics were almost identical in those with lung tumors harboring EGFR mutations and HER2-IHC2+/3+ (group P) or EGFR mutations and HER2-IHC0/1 (group N). The EGFR-TKI response rates were not different between these groups (Table). However, group P showed significantly shorter time to EGFR-TKI treatment failure than group N (median 19.1 vs. 13.3 months; log rank p = 0.038). Conclusions: These data from a large prospective cohort show that HER2 protein expression in EGFR-mutant NSCLC may have a negative impact on the effect of EGFR-TKIs. A clinical trial of EGFR/HER2-TKIs (e.g., afatinib) is warranted for this population. [Table: see text]

Abstract P1-03-02: ASCO/CAP human epidermal growth factor receptor-2 (HER2) in situ hybridization (ISH) categories evaluated by quantitative HER2 protein diagnostic methodologies: A comparative analysis

Abstract Background: In 2013, the ASCO/CAP consensus panel published updated guidelines for HER2 testing in breast cancer that modified the definition of HER2 amplification by in situ hybridization (ISH), creating five new prognostic categories (group 1: classic amplified, group 2: monosomy, group 3: co-amplified (polysomy), group 4: equivocal, and group 5: classic non-amplified). Patients determined to be ISH amplified, were considered eligible for HER2-directed therapy. Concern over whether patients from non-classic groups 2-4 would benefit from treatment has led to the recent publication of the 2018 HER2 focused update. This update has modified the criteria for interpreting these ISH categories, recommending that the final diagnosis take into consideration a combination of HER2 immunohistochemistry (IHC) and ISH results. With increased emphasis on the HER2 protein assessment, it has prompted us to quantitatively examine HER2 protein expression in the ISH categories, using two different novel technologies. Materials &amp; Methods: A cohort of 170 cases (URMC) and 102 cases (PSHMC) of invasive breast cancers, which had previously undergone HER2 IHC and ISH testing, were selected for this study. Cases were sorted and categorized into the HER2 ISH categories defined by ASCO/CAP. HER2 protein expression was quantitatively measured in the URMC and PSHMC cohorts using a novel immunodetection methodology (streptavidin-coated Phosphor-Integrated Dot (PID) fluorescent nanoparticles), and a novel dual-antibody, proximity-binding immunoassay (HERmark® Breast Cancer Assay, Monogram Biosciences, South San Francisco, California), respectively. HER2 protein expression was compared to the HER2 FISH and IHC results by ASCO/CAP category. Results: Cases in group 1 had a significantly (p &amp;lt; 0.01) higher average PID/cell and HERmark compared to cases in groups 2-5 (Table 1). Cases in groups 2-4 showed lower quantitative levels of HER2 protein expression, similar to the classic non-amplified cases (group 5). Group 1 was further divided into three subgroups (Table 2): Group A - ISH high-level amplified (ratio &amp;gt; 2, HER2 &amp;gt; 6, CEP17 &amp;lt; 2.7), Group B - amplified with elevated CEP17 (ratio &amp;gt; 2, CEP17 &amp;gt; 2.7), and Group C - low-level amplified (ratio &amp;gt; 2, HER2 &amp;gt; 4 and &amp;lt; 6). Group A and B had a significantly (p &amp;lt; 0.01) higher average PID/cell and HERmark compared to Group C. Group C was more comparable to cases in groups 2-5 (Table 1). Conclusion: Our results suggest that quantitative assessment of HER2 protein expression may help to further classify cases for HER2 status for targeted therapy, supporting the 2018 ASCO/CAP recommendation that non-classic ISH results might be resolved by evaluating protein expression. Follow up studies with a larger patient cohort and dual quantitative assessment are warranted. Average PID/cell and HERmark in ASCO category groupsASCO category groupN (URMC)PID/cell (URMC)*N (PSHMC)HERmark (PSHMC)*18888.07761.521011.20N/A32016.0213.84238.5315.95296.3208.3*averageTable 2:Average PID/cell and HERmark in subgroups of Group 1SubgroupN (URMC)PID/cell (URMC)*N (PSHMC)HERmark (PSHMC)*A24157.66465.7B34101.61044.1C3016.9329.8*average Citation Format: Buscaglia B, Turner B, Goda H, Huang W, Leitzel K, Natori T, Nakano Y, Okada H, Sperinde J, Ali S, Vasekar M, D'Aguiar M, McMahon L, Henry J, Lipton A, Hicks D. ASCO/CAP human epidermal growth factor receptor-2 (HER2) in situ hybridization (ISH) categories evaluated by quantitative HER2 protein diagnostic methodologies: A comparative analysis [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-03-02.

Investigating the Levels of Shed Extracellular Domain of HER2 Protein in the Sera of Bladder Cancer Patients

Background: Receptor tyrosine-protein kinase ERBB2, also known as human epidermal growth factor receptor-2 (HER2), is heterogeneously expressed in a variety of human cancers, including bladder cancer. Based on previous studies that show its association with bladder cancer progression, HER2 has been included in novel multiplatform biomarkers for prediction of bladder cancer prognosis. However, the clinical significance of HER2 status remains underinvestigated and poorly linked to the patients’ clinicopathological features. Here, we aim to scrutinize the levels of the extracellular domain of HER2 in the sera of bladder cancer patients and correlate these levels with clinicopathological features of the tumor.Methods: In the present analytical cross-sectional study, we enrolled 60 pathologically confirmed bladder cancer patients along with 20 age-sex matched healthy controls, and compared their serum HER2 levels as measured by enzyme-linked immunosorbent assay.Results:We observed no statistically significant difference when comparing the levels of HER2 in the sera of cases and controls (P>0.05). Interestingly, serum HER2 levels of controls were higher than bladder cancer patients who had lymph node metastasis (P=0.036). Serum levels of HER2 were also higher in controls than bladder cancer patients with perineural invasion (P=0.028). We observed significantly higher HER2 serum levels in transitional cell carcinoma patients in comparison to non-transitional cell carcinoma patients (P=0.016).Conclusion: Our observations are suggestive of the absence of any association between bladder cancer prognostic factors and serum HER2 levels. To draw any definitive conclusion, further studies with larger sample sizes that examine the presence of neutralizing auto-antibodies against serum HER2, immunohistochemistry examination of HER2 in bladder tumor and lymph node samples, and urinary HER2 levels, along with measurement of its serum levels would be helpful.

A novel detection methodology for HER2 protein quantitation in formalin-fixed, paraffin embedded clinical samples using fluorescent nanoparticles: an analytical and clinical validation study

BackgroundClinical assays for the assessment of the human epidermal growth factor receptor-2 (HER2) status in breast cancer include immunohistochemistry (IHC) and in situ hybridization (ISH), both of which have limitations. Recent studies have suggested that a more quantitative approach to the measurement of HER2 protein expression may improve specificity in selecting patients for HER-2 targeted therapy. In the current study, we have used HER2 expression in breast cancer cell lines and clinical samples as a model to explore the potential utility of a novel immunodetection technique, using streptavidin coated Phosphor Integrated Dot fluorescent nanoparticles (PID), which can be quantitatively measured using computer analysis.MethodsThe expression of HER2 protein in cell lines was evaluated with antibody-binding capacity using fluorescence-activated cell sorting (FACS) for comparison with PID measurements to test for correlations with existing quantitative protein analysis methodologies. Various other analytic validation tests were also performed, including accuracy, precision, sensitivity, robustness and reproducibility. A methods comparison study investigated correlations between PID versus IHC and ISH in clinical samples. Lastly, we measured HER2 protein expression using PID in the pretreatment biopsies from 34 HER2-positive carcinomas that had undergone neoadjuvant trastuzumab-based chemotherapy.ResultsIn the analytic validation, PID HER2 measurements showed a strong linear correlation with FACS analysis in breast cell lines, and demonstrated significant correlations with all aspects of precision, sensitivity, robustness and reproducibility. PID also showed strong correlations with conventional HER2 testing methodologies (IHC and ISH). In the neoadjuvant study, patients with a pathologic complete response (pCR) had a significantly higher PID score compared with patients who did not achieve a pCR (p = 0.011), and was significantly correlated to residual cancer burden (RCB) class (p = 0.026, R2 = 0.9975).ConclusionsAnalytic testing of PID showed that it may be a viable testing methodology that could offer advantages over other experimental or conventional biomarker diagnostic methodologies. Our data also suggests that PID quantitation of HER2 protein may offer an improvement over conventional HER2 testing in the selection of patients who will be the most likely to benefit from HER2-targeted therapy. Further studies with a larger cohort are warranted.

Cleavage of the extracellular domain of junctional adhesion molecule-A is associated with resistance to anti-HER2 therapies in breast cancer settings

BackgroundJunctional adhesion molecule-A (JAM-A) is an adhesion molecule whose overexpression on breast tumor tissue has been associated with aggressive cancer phenotypes, including human epidermal growth factor receptor-2 (HER2)-positive disease. Since JAM-A has been described to regulate HER2 expression in breast cancer cells, we hypothesized that JAM-dependent stabilization of HER2 could participate in resistance to HER2-targeted therapies.MethodsUsing breast cancer cell line models resistant to anti-HER2 drugs, we investigated JAM-A expression and the effect of JAM-A silencing on biochemical/functional parameters. We also tested whether altered JAM-A expression/processing underpinned differences between drug-sensitive and -resistant cells and acted as a biomarker of patients who developed resistance to HER2-targeted therapies.ResultsSilencing JAM-A enhanced the anti-proliferative effects of anti-HER2 treatments in trastuzumab- and lapatinib-resistant breast cancer cells and further reduced HER2 protein expression and Akt phosphorylation in drug-treated cells. Increased epidermal growth factor receptor expression observed in drug-resistant models was normalized upon JAM-A silencing. JAM-A was highly expressed in all of a small cohort of HER2-positive patients whose disease recurred following anti-HER2 therapy. High JAM-A expression also correlated with metastatic disease at the time of diagnosis in another patient cohort resistant to trastuzumab therapy. Importantly, cleavage of JAM-A was increased in drug-resistant cell lines in conjunction with increased expression of ADAM-10 and -17 metalloproteases. Pharmacological inhibition or genetic silencing studies suggested a particular role for ADAM-10 in reducing JAM-A cleavage and partially re-sensitizing drug-resistant cells to the anti-proliferative effects of HER2-targeted drugs. Functionally, recombinant cleaved JAM-A enhanced breast cancer cell invasion in vitro and both invasion and proliferation in a semi-in vivo model. Finally, cleaved JAM-A was detectable in the serum of a small cohort of HER2-positive patients and correlated significantly with resistance to HER2-targeted therapy.ConclusionsCollectively, our data suggest a novel model whereby increased expression and cleavage of JAM-A drive tumorigenic behavior and act as a biomarker and potential therapeutic target for resistance to HER2-targeted therapies.

Kahweol inhibits proliferation and induces apoptosis by suppressing fatty acid synthase in HER2-overexpressing cancer cells

Kahweol is a coffee-specific diterpene found in the beans of Coffea arabica and has been reported to demonstrate various biological activities, including anti-inflammatory, antioxidant, and apoptotic properties. In the present study, we examined the molecular mechanism of kahweol in human epidermal growth factor receptor-2 (HER2)-overexpressing breast cancer cells. Kahweol preferentially inhibited cell proliferation and induced cell death through the induction of a caspase 3-dependent pathway in HER2-overexpression breast cancer cell lines. Kahweol treatment substantially reduced the levels of HER2 protein, mRNA, and transcriptional activity in SKBR3 cells. Kahweol exerts its potent anticancer efficacy by the upregulation of polyomavirus enhancer activator 3 (PEA3) and downregulation of activator protein 2 (AP-2) to inhibit aberrantly activated HER2 signaling. Fatty acid synthase (FASN) expression and sterol regulatory element-binding protein-1c (SREBP-1c) activity were downregulated by kahweol. In addition, kahweol lowered the levels of phosphorylated Akt and its downstream targets mammalian target of rapamycin (mTOR) and cyclin D1. Furthermore, we found that blocking Akt signaling through kahweol treatment significantly reduced FASN expression and subsequently suppressed cell proliferation in HER2-overexpressing cancer cells. Overall, this study suggests that kahweol could be a useful adjuvant therapeutic agent in the treatment of HER2-overexpressing breast cancer.

HER2 status in patients with residual rectal cancer after preoperative chemoradiotherapy: the relationship with molecular results and clinicopathologic features.

The specific role of human epidermal growth factor receptor-2 (HER2) status in rectal cancers remains unclear. This study therefore aimed to explore clinicopathologic and molecular characteristics, and prognostic value of HER2-positivity in residual mid- and/or low-rectal cancers after preoperative chemoradiotherapy (CRT). Surgical specimens from 145 patients with residual rectal cancer after preoperative CRT between January 2006 and January 2011 were used to evaluate HER2 status. HER2 protein expression and gene amplification were determined using immunohistochemistry (IHC) and silver in situ hybridization (SISH) on whole tissue sections, respectively. Polymerase chain reaction was used to analyze molecular characteristics, including microsatellite instability (MSI) and mutations in KRAS exon 2 (codon 12 and 13) and BRAF V600E mutation. Of 139 eligible patients, 8 (5.8%) had HER2 overexpression (IHC 2+ and 3+) that was not associated with clinicopathologic characteristics and patient survival, except positive circumferential resection margin (CRM) (P = 0.012). SISH was performed on 24 patient samples with IHC 1+ (n = 16), 2+ (n = 6), and 3+ (n = 2). HER2 amplification was identified in 3 patients (2.2%); however, this was also associated with positive CRM (P = 0.009) but not survival (all P > 0.05). Moreover, HER2 overexpression and amplification had no relationship with KRAS or BRAF mutations, and MSI status (all P > 0.05). HER2 positivity was found in a minority of rectal cancer patients and was not significantly associated with clinicopathologic and molecular characteristics. Our findings can be helpful in understanding the clinicopathologic bases of HER2 status in rectal cancers.

PO-500 A novel role for junctional adhesion molecule-a (JAM-A) in HER2-positive gastro-oesophageal cancers

IntroductionJunctional Adhesion Molecule-A (JAM-A) is a cell-cell adhesion protein that regulates physiological adhesion in epithelial and endothelial cells. Our previous work has shown that increased JAM-A expression on breast tumour epithelial tissue associates with poor prognosis in patients with invasive breast cancer, and identified a correlation between high JAM-A expression and levels of the important oncogene human epidermal growth factor receptor-2 (HER2). An important role for HER2 in gastro-oesophageal cancer is emerging, however the specific role of JAM-A in this setting is unclear.Material and methodsIn a pilot study, gastric cancer patient tissue sections (n=11) were stained for JAM-A expression. A novel, weighted ranking system was developed to semi-quantitatively score the extremely heterogeneous JAM-A membranous staining in gastric tissues; ultimately ranking tissues as low, moderate or high JAM-A expression. JAM-A scores were also correlated with HER2 status in each section. In parallel, a panel of gastro-oesophageal cell lines was used to investigate potential molecular relationships between JAM-A and HER2. Finally, HER2 protein expression was examined following transient JAM-A gene silencing in the gastro-oesophageal junction cancer cell line ESO26.Results and discussionsThe pilot study revealed that high JAM-A expression significantly correlated with HER2 positivity, and noted a novel staining pattern for JAM-A in diffuse gastric cancers. Molecular studies showed that JAM-A gene silencing reduced HER2 protein expression in gastric cancer cells. These data suggests that JAM-A may act as a novel upstream regulator of HER2 in gastro-oesophageal cancer cells, and warrant further investigation. Current studies are focussed on elucidating the mechanisms underpinning regulation of HER2 expression by JAM-A.ConclusionPromising preliminary indications that JAM-A plays a role in regulating HER2 expression in non-breast cancers may suggest it as both an unfavourable biomarker, as well as a novel putative pharmacological target for HER2-positive gastro-oesophageal cancers.This abstract has emanated from research conducted with the financial support of Science Foundation Ireland (SFI) under grant number 13/IA/1994 (to AMH).

Evaluation of the HER2 and Hormone Receptor Status in Metastatic Breast Cancer Using Cell Blocks: A Multi-Institutional Study

Objective: We explore the problems associated with the cell block (CB) method for receptor analysis in breast cancer metastases and propose a method for reporting the results. Study Design: Nine institutions used the CB method for the analysis of hormone receptors (HRs) and HER2 (human epidermal growth factor receptor 2) protein in cytological specimens of breast cancer metastases in routine practice. The stained slides were independently evaluated by 8 pathologists. Dual in situ hybridization assay was performed in cases of discordant results for HER2 protein. Based on the results, we propose a method for receptor scoring in the CB method. Results: Of 61 specimens, 57 contained tumor cells. Two or more pathologists disagreed on the results for the estrogen receptor, progesterone receptor, and HER2 protein in 3 (5.3%), 13 (22.8%), and 19 (33.3%) cases, respectively. The discrepant results for the HRs were attributed to the presence of a few positive cells or faintly stained cells. The high interobserver discordance rate for HER2 protein was explained by interobserver differences in the scoring criteria. Conclusion: The use of categorical scoring into positive and negative is recommended for evaluating the HR expressions. Use of strict criteria for HER2 protein 2+ and 3+ cases is recommended, as HER2-positive cases should not be missed.

Abstract P2-09-28: New quantitative diagnostic method by fluorescence nanoparticle for HER2 positive breast cancer treated with neoadjuvant lapatinib and trastuzumab: The Neo LaTH study (JBCRG-16TR)

Abstract Background: HER2 (human epidermal growth factor receptor 2) testing performed by IHC (immunohistochemical) methods and FISH (fluorescence in situ hybridization) is semi-quantitative. Exact quantification of HER2 is needed to predict which patients are more or less likely to response to anti HER2 therapy. To improve the method for cancer patients' HER2 status, we developed a novel fluorescence IHC method using new fluorescence nanoparticle. The fluorescent intensity of this new nanoparticles, termed phosphor-integrated dot (PID), was approximately 100-fold brighter than that of Quantum dots. Because of its increased brightness and analyzing technology, this PID-based fluorescent IHC(IHC-PIC) has an ability of quantifying the biomarker protein in the cancer tissue sample at single particle level. In this study, the primary objective was to investigate if pathological complete response (pCR) rate in HER2- positive breast cancer treated by trastuzumab and lapatinib containing neoadjuvant systemic therapy would depend on the level of HER2, EGFR, HER3, Ki67, ER and PgR protein quantified by this new method. Methods: The Neo-LaTH study is a randomized phase II multicenter trial evaluating the efficacy and safety of lapatinib and trastuzumab followed by lapatinib and trastuzumab plus weekly paclitaxel with or without prolongation of anti-HER2 therapy prior to chemotherapy (18 weeks vs. 6 weeks). The primary endpoint was the comprehensive pCR rate. We evaluated the HER2, EGFR, HER3, Ki67, ER and PgR amount by nano-patho method using PID in formalin-fixed paraffin-embedded core biopsy samples taken at diagnosis retrospective analysis. Univariate and multivariate analyses were performed to determine the association between pCR and variables, including HER2, EGFR, HER3, Ki67, ER and PgR nano-patho score and clinicopathological factors including histological grade, tumor status, nodal status and HER2 FISH ratio. Results: A total of 96 tumor samples from patients were used for the present analysis.The pCR rate was 60.4%. We obtained the images of only PID signal by the image analyses, and calculated the number of PID particles in a cell and defined it as IHC-PID score that reflects the level of HER2, EGFR, HER3, Ki67, ER and PgR protein expression in cancer cells. Univariate analysis showed that HER2 IHC-PID score(p&amp;lt;0.0001), ER IHC-PID score(p=0.009) and PgR IHC-PID score(p=0.019) were associated with pCR and multivariate analysis showed that HER2 IHC-PID score was significantly associated with pCR (adjusted odds ratio, 0.990 [95% CI, 0.984–0.996]; P &amp;lt; .0001). Conclusion: We successfully performed the quantitative IHC-PID for HER2, EGFR, HER3, Ki67, ER and PgR. And we propose using HER2 IHC-PID score as a predictive factor for trastuzumab and lapatinib containing neoadjuvant systemic therapy. This quantitative diagnostic method would be expected to contribute to the development of a molecular therapeutic strategy. Citation Format: Tada H, Miyashita M, Gonda K, Watanabe M, Suzuki A, Watanabe G, Harada N, Sato A, Hamanaka Y, Masuda N, Toi M, Ohno S, Bando H, Ishiguro H, Inoue K, Yamamoto N, Kuroi K, Ohuchi N, Ishida T. New quantitative diagnostic method by fluorescence nanoparticle for HER2 positive breast cancer treated with neoadjuvant lapatinib and trastuzumab: The Neo LaTH study (JBCRG-16TR) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-09-28.

HER-2 Protein Overexpression in Patients with Gastric and Oesophageal Adenocarcinoma at a Tertiary Care Facility in Ghana.

The prognosis of gastric and oesophageal adenocarcinoma remains generally poor. However, mounting evidence suggests a positive role of human epidermal growth factor receptor-2 (HER-2) expression in the prognosis of patients with these cancers. In this work, the patterns of HER-2 protein expression were determined in patients with gastric or oesophageal adenocarcinoma. Retrospectively, we reviewed records of gastric and oesophageal biopsies received from 2008 to 2012 and their corresponding archived formalin-fixed paraffin-embedded tissue blocks selected for immunohistochemical analysis. The prevalence of gastric and oesophageal adenocarcinomas and their association with HER-2 protein overexpression were evaluated. Gastric adenocarcinoma made up 18.79% of the gastric biopsies reviewed, and majority of these cancers occurred in males. Regarding the tumour type, HER-2 overexpression was common in the intestinal subtype compared to the diffuse type. Although squamous cell carcinoma was observed to be the commonest (31%) tumour type in the oesophagus compared to adenocarcinoma (8.79%), HER-2 was overexpressed in 42.9% of oesophageal adenocarcinomas, like gastric adenocarcinoma (41.4%). There is a high prevalence of gastric and oesophageal adenocarcinoma, with significant overexpression of HER-2 in these tumours, a window of hope for the management of patients with these cancers.

Abstract P1-03-10: HER2 expression in clinical breast cancer samples: A novel detection methodology for HER2 protein quantitation using fluorescent nanoparticles

Abstract Background: The human epidermal growth factor receptor-2 (HER2) is a member of a family of transmembrane tyrosine kinase receptors that play an important role in regulated normal cell growth and differentiation. The over-expression of HER2 in a subset of 15-20% of invasive breast cancers has an important bearing on prognosis, as HER2-positive tumors are associated with an aggressive clinical course and poor outcome. Targeting HER2-overexpression has been shown to be a remarkably effective therapeutic modality; however testing of tumor samples to assess the HER2 status of the patient's breast cancer is required. Clinical assays to assess the HER2 status in patients being considered for targeted therapy include immunohistochemistry (IHC), which detects protein over-expression, or fluorescence in situ hybridization (FISH), which detects gene amplification. Both the IHC and FISH methodologies have limitations. Given that the target of the currently approved drugs is the receptor protein, novel detections systems that could more accurately and quantitatively detect HER2 protein in clinical samples over a broad dynamic range would be advantageous and may be clinically helpful. Material and Methods: A novel detection technology using streptavidin-coated Phosphor Integrated Dot fluorescent nanoparticles (PID) has been developed that can be visualized by fluorescence microscopy and used for quantitative immunofluorescence detection of protein in clinical samples using computer assisted image analysis. In the current study, PID- nanoparticles were used to analyze HER2 protein expression in breast cancer cell lines and 120 well characterized breast cancer samples. These results have been compared with HER2 IHC and HER2 FISH analysis. Results: The expression levels of HER2 protein from 8 breast cancer cell lines was evaluated by antibody-binding capacity with FACS analysis. Formalin fixed paraffin embedded cell pellets for these cell lines were prepared and used for quantitative HER2 analysis by PID. The PID score/cell for each of these cell lines showed a strong linear correlation with antibody-binding capacity sites/cell by FACS analysis (R2 = 0.94). For the 120 breast cancer samples, PID score/cell was measured and compared against HER2 IHC membrane intensity measure by image analysis (Aperio) and HER2 FISH results. The HER2 PID score/cell showed a correlation coefficient of R2=0.72 versus the average HER2 copy number per cell by FISH, compared with a correlation coefficient of R2=0.41 for HER2 IHC membrane intensity measured by Aperio. For the HER2/CEP17 ratio, the correlation coefficient for the PID score/cell was R2=0.79 compared with a correlation coefficient of R2=0.32 for the HER2 IHC membrane intensity. Conclusions: PID-nanoparticles demonstrate great potential for the quantitative measurement of protein of clinical interest in routine clinical samples with morphologic confirmation of the tissue being studied. Further studies looking for PID-score thresholds for HER2 gene amplification and correlations with clinical outcome data are warranted and ongoing. Citation Format: Hicks DG, Goda H, Zhai H, Okada H, McMahon L, Sullivan N, Tang P, Nakano Y. HER2 expression in clinical breast cancer samples: A novel detection methodology for HER2 protein quantitation using fluorescent nanoparticles [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-03-10.

Development of a quantitative PCR assay to evaluate HER2 status of Gastric carcinoma in a cohort of Sri Lankan patients

Introduction Human epidermal growth factor receptor2 (HER2) protein over expression and/or HER2gene amplification are/is linked to dismal outcome of Gastric carcinoma (GCa). Immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) are key-methods to identify patients for HER2 targeted therapy. Drawbacks of both methods warrant novel-tests. Objective To determine whether quantitative Polymerase Chain Reaction (qPCR) could serve as a supplementary-method to evaluate HER2 status of GCa in a cohort of Sri Lankan patients and investigate correlation between HER2 assessed by different methods and clinicopathological features. Methods Twenty GCa-patients with known IHC-HER2 scores were evaluated. qPCR was performed for HER2 gene and Ameloid precursor protein (reference gene) in Formalin fixed paraffin embedded GCa tissue. Threshold values (Ct) were analyzed using Pfaffl-method to detect HER2 gene amplification. Results HER2positivity by IHC (protein) and qPCR (gene) were 20% and 35% respectively. Sensitivity and specificity of qPCR was 67% and 76% respectively and results were reproducible. HER2 protein positivity was correlated with Tumour TNM-stage and Lauren-histological types (P Discussion & Conclusion Discrepancies between HER2 positivity by IHC and qPCR were possibly due to transcription activation by other genes in the absence of HER2 gene amplification and the aberrant form of HER2 protein not detected by IHC. Studies also indicate a higher-proportion of IHC negative, but HER2gene amplified GCa by FISH. qPCR may be used as a supplementary-method for detection of HER2 status of GCa in local setting.

Application of a quantitative PCR assay to evaluate Human Epidermal Growth Factor Receptor - 2 status of Gastric carcinoma in a cohort of Sri Lankan patients

Introduction Human epidermal growth factor receptor2 (HER2) protein over expression and/or HER2 gene amplification is linked to dismal outcome of gastric carcinoma (GCa). Immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) are key methods to identify patients for HER2 targeted therapy. Draw backs of both methods warrant novel tests. The objectives were to determine whether quantitative Polymerase Chain Reaction (qPCR) could serve as a supplementary method to evaluate HER2 status of GCa and investigate the correlation between HER2 assessed by different methods and clinicopathological features. Methodology Twenty GCa patients with known IHC-HER2 scores were evaluated. qPCR was performed for HER2 gene and Amyloid precursor protein (reference gene) in formalin fixed paraffin embedded GCa tissue. Threshold values (Ct) were analyzed using Pfaffl-method to detect HER2 gene amplification. Results HER2 positivity by IHC (protein) and qPCR (gene) were 20% and 35% respectively. Sensitivity and specificity of qPCR was 67% and 76% respectively and results were reproducible. HER2 protein positivity was correlated with TNM-stage and Lauren histological types (P Discussion Discrepancies between HER2 positivity by IHC and qPCR were possibly due to transcription activation by other genes in the absence of HER2 gene amplification and the aberrant form of HER2 protein not detected by IHC. Studies also indicate a higher proportion of IHC negative, but HER2 gene amplified GCa by FISH. Conclusion qPCR may be used as a supplementary method for evaluation of HER2 status in gastric carcinoma proven to be HER2 negative by immunohistochemistry.

Human Epidermal Growth Factor Receptor-2 (HER2) expression in Gastric adenocarcinoma and relevant clinicopathological features in a cohort of Sri Lankan patients

Introduction Human epidermal growth factor receptor -2 (HER2) gene over-expression heralds adverse prognosis in gastric adenocarcinoma (GCa). HER2 protein over-expression by immunohistochemistry (IHC) ranges from 10%-22.8% and 11.7%-15.74% in Western and Asian studies respectively. We aimed to evaluate HER2 positivity in GCa by IHC and to study relevant clinicopathological relationships, as information is locally unavailable. Methodology Hundred consecutive GCa (excluding gastrooesophageal junction tumours) were recruited prospectively from the National Hospital of Sri Lanka over two years. The diagnosis was made on endoscopic biopsy/gastrectomy specimens. HER2 was assessed in paraffinized tumour using c-erB-2 oncoprotein (DAKO A0485) and Real-TM Envision system. Scores of 2+ and 3+ were considered positive, using standard HER2 expression criteria. Relationship between HER2 and clinicopathological parameters were analyzed using SPSS-21 and Chi-squared test. Results Study included 44 gastrectomies and 56 biopsies. Mean age was 61.1 years (range 32- 82). HER2 was positive in 9 (9%) GCas: 2+ in 3(5.4%) biopsies and 3(6.8%) resections, 3+ in 1(1.8%) biopsy and 2(4.5%) resections. Eight (88.9%) HER2 positive GCa occurred in =T3) (p=0.31). HER2 positive cases showed, poor differentiation (p=0.047), higher nuclear grade (p=0.029), mitotic counts >5/HPF (p=0.003), extracellular mucin (p=0.05), tumour necrosis (p=0.037), perineural invasion (p=0.002) and nodal metastasis (p=0.04) assessed only in gastric resections. Discussion and conclusion HER2 positivity with immunohistochemistry was 9% in the gastric carcinoma cohort and were associated with higher stage, adverse histological parameters and nodal metastasis in gastric resections. Adverse histological features can be used as screening features for HER2 testing in gastric carcinoma in limited resource settings.

Expression of Hypoxia-Inducible Factor 1α in Invasive Breast Cancer with Metastasis to Lymph Nodes: Correlation with Steroid Receptors, HER2 and EPO-R.

Expression of hypoxia-inducible factor 1α (HIF-1α) reflects the degree of cell hypoxia and its increased expression was found in most neoplasms, their metastasis as well as in some precancerous lesions. The study aimed to investigate the expression HIF-1α in invasive breast cancer with metastasis to lymph nodes in correlation with steroid receptors (ER-estrogen receptor, PR-progesterone receptor), HER2 (human epidermal growth factor receptor 2) and EPO-R (erythropoietin receptor). A total of 58 cases of invasive breast cancer with metastasis to lymph nodes were assessed for expression of HIF-1α, EPO-R, ER, PR and HER2. In our study, among all invasive breast cancers, 36.2% exhibited HIF-1α expression in the nuclei of neoplastic cells. We also assessed the correlation between histological type of cancer and basic immunohistochemical profile that included HIF-1α expression and statistical significance was noted only in the case of PR-/ER-/HER2-/ /HIF-1α-/ and PR+/ER+/HER2-/HIF-1α-/ (p = 0.028 and p = 0.008, respectively). However, only in the case of the PR+/ER+/HER2-/HIF-1α+/ immunohistochemical profile and histological grading did we note a statistical significance (p = 0.006). Expression of HIF-1α was most often noted in cancers exhibiting expression of HER2 protein (57.14%). Our study also assessed the relationship between the expression of HIF-1α in invasive breast cancers and the expression of EPO-R and areas of necrosis, demonstrating a statistically significant dependence (p = 0.003). Expression of HIF-1α was more often noted in invasive HER2+ cancers characterized by high degree of aggressiveness and poorer prognosis, which might suggest that presence of HIF-1α protein expression in HER2+ cancers could be an additional prognostic factor, the frequent occurrence of the phenotype of HIF-1α and EPO-R in cancers invasive HER2 +, in the absence of ER and PR, may suggest that HIF-1α and EPO-R may be an indicator of the aggressiveness of invasive breast cancers, indicating the need for a specific forms of treatment in this group of patients.

High HER2 protein levels correlate with increased survival in breast cancer patients treated with anti-HER2 therapy

IntroductionCurrent methods to determine HER2 (human epidermal growth factor receptor 2) status are affected by reproducibility issues and do not reliably predict benefit from anti-HER2 therapy. Quantitative measurement of HER2 may more accurately identify breast cancer (BC) patients who will respond to anti-HER2 treatments. MethodsUsing selected reaction monitoring mass spectrometry (SRM-MS), we quantified HER2 protein levels in formalin-fixed, paraffin-embedded (FFPE) tissue samples that had been classified as HER2 0, 1+, 2+ or 3+ by immunohistochemistry (IHC). Receiver operator curve (ROC) analysis was conducted to obtain optimal HER2 protein expression thresholds predictive of HER2 status (by standard IHC or in situ hybridization [ISH]) and of survival benefit after anti-HER2 therapy. ResultsAbsolute HER2 amol/μg levels were significantly correlated with both HER2 IHC and amplification status by ISH (p < 0.0001). A HER2 threshold of 740 amol/μg showed an agreement rate of 94% with IHC and ISH standard HER2 testing (p < 0.0001). Discordant cases (SRM-MS-negative/ISH-positive) showed a characteristic amplification pattern known as double minutes. HER2 levels >2200 amol/μg were significantly associated with longer disease-free survival (DFS) and overall survival (OS) in an adjuvant setting and with longer OS in a metastatic setting. ConclusionQuantitative HER2 measurement by SRM-MS is superior to IHC and ISH in predicting outcome after treatment with anti-HER2 therapy.