Sensitivity to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) and frequency of activation mutations in EGFR is lower in Caucasian than Asian non small-cell lung cancer (NSCLC) patients. Increased EGFR gene copy numbers evaluated by fluorescence in situ hybridization (FISH) has been reported as predictor of clinical benefit from EGFR-TKIs in Caucasian NSCLC patients. This study was carried out to verify whether EGFR FISH had similar performance in Japanese patients.
A cohort of 44 Japanese patients with recurrent NSCLC after surgery was treated with gefitinib 250 mg daily. The cohort included 48% females and 52% never-smokers; 73% had prior chemotherapy and 57% had stage III-IV at the time of surgery. Adenocarcinoma was the most common histology (86%). FISH was performed using the EGFR/Chromosome Enumeration Probe 7 and PathVysion DNA probes (Abbott Molecular). Specimens were classified as FISH positive when showing gene amplification or high polysomy (≥4 copies of the gene in ≥40% of tumor cells). Tumor response to gefitinib was assessed by RECIST for 33 patients with measurable diseases.
Twenty-nine tumors (66%) were EGFR FISH+ and 23 (53%) were HER2 FISH+. Overall response rate was 52%, representing 65% of EGFR FISH+ patients and 29% of EGFR FISH+ patients (p = 0.0777). Survival was not impacted by the EGFR FISH (p = 0.9395) or the HER2 FISH (p = 0.0671) status. EGFR FISH= was significantly associated with HER2 FISH+ (p = 0.015) and presence of EGFR mutation (p = 0.0060). EGFR mutation significantly correlated with response (p < 0.0001) and survival after gefitinib (p = 0.0204). EGFR and HER2 FISH status were not associated with KRAS mutation.
Frequency of EGFR FISH+ status was higher and its predictive power for TKI sensitivity was lower in this Japanese cohort than in Western NSCLC cohorts. These findings support differences in the mechanisms of EGFR pathway activation in NSCLC between Asian and Caucasian populations. Confirmation of these results in larger cohorts is warranted.
FISH; EGFR; HER2; KRAS; Biomarkers; NSCLC; Tyrosine inhibitors
Biliary tract cancers (BTC) are uncommon in the United States, but are endemic in parts of South America and Asia. BTCs are aggressive tumors associated with poor survival. Activation of HER-2/neu (erbB2) and/or epidermal growth factor receptor (EGFR) are important in breast, colon, and lung cancers. Tumor specimens from patients from the United States and Chile were examined for expression of HER-2/neu, EGFR, and their activated forms (p-erbB2, p-EGFR).
Materials and Methods
Specimens from 77 gallbladder cancers (GBC), 16 extrahepatic bile duct cancers (EHBDC), 21 intrahepatic bile duct cancers (IHBDC), 11 cases of cholecystitis (CHOLE), and 8 normal gallbladders (NGB) were examined for HER-2/neu, p-erbB2, EGFR, and p-EGFR expression by immunohistochemistry (IHC), with scores of 2+ or 3+ defined as positive. HER-2/neu gene amplification was analyzed by double color HER-2/neu gene/chromosome 17 centromere (CEP17) fluorescence in situ hybridization (FISH) assays
HER-2/neu-positive IHC staining was found in 31.2% of GBC, 31.3%, of EHBDC, and 33.3% of IHBDC; 12.5% of CHOLE specimens showed 2+ staining and the remaining CHOLE and NGB were negative. HER-2/neu gene amplification was detected in 20.9% of GBC, 21.4% of EHBDC, and none of IHBDC. There was a significant correlation between IHC 2+ and 3+ and gene amplification (P =.0001).
HER-2/neu amplification was identified in more than 20% of GB and EHBDC. There was strong correlation between HER-2/neu IHC and FISH positivity. These findings indicate a role for HER-2/neu in some subsets of BTC, and provide a rationale for study of HER-2/neu-directed therapies in this setting.
Lapatinib, a dual tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR/ErbB1) and human epidermal growth factor receptor 2 (HER-2/ErbB2), is effective against HER-2–positive locally advanced or metastatic breast cancer (MBC). This phase III trial evaluated the efficacy of lapatinib in HER-2–negative and HER-2–uncharacterized MBC.
Patients and Methods
Women with MBC were randomly assigned to first-line therapy with paclitaxel 175 mg/m2 every 3 weeks plus lapatinib 1,500 mg/d or placebo. A preplanned retrospective evaluation of HER-2 status was performed using fluorescence in situ hybridization and immunohistochemistry. The primary end point was time to progression (TTP); secondary end points were objective response rate (ORR), clinical benefit rate (CBR), event-free survival (EFS), and overall survival (OS).
In the intent-to-treat population (n = 579), there were no significant differences in TTP, EFS, or OS between treatment arms, although differences in ORR and CBR were noted. In 86 HER-2–positive patients (15%), treatment with paclitaxel-lapatinib resulted in statistically significant improvements in TTP, EFS, ORR, and CBR compared with paclitaxel-placebo. No differences between treatment groups were observed for any end point in HER-2–negative patients. The most common adverse events were alopecia, rash, and diarrhea. The incidence of diarrhea and rash was significantly higher in the paclitaxel-lapatinib arm. The rate of cardiac events was low, and no difference was observed between treatment arms.
Patients with HER-2–negative or HER-2–untested MBC did not benefit from the addition of lapatinib to paclitaxel. However, first-line therapy with paclitaxel-lapatinib significantly improved clinical outcomes in HER-2–positive patients. Prospective evaluation of the efficacy and safety of this combination is ongoing in early and metastatic HER-2–positive breast cancer patients.
Lapatinib is a dual inhibitor of epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) with activity in HER2-amplified metastatic breast cancer (MBC). Its role in non–HER2-amplified MBC remains unclear. EGF30001, a phase III trial of lapatinib and paclitaxel versus paclitaxel and placebo, demonstrated lapatinib does not significantly benefit HER2-negative or HER2-unselected patients with MBC. Published data support interactions between steroid hormone and peptide growth factor signaling. We hypothesized that molecular subgroups may exist within EGF30001 that would benefit from lapatinib.
A blinded, retrospective biomarker evaluation was performed using immunohistochemistry to semiquantitate estrogen (ER), progesterone (PR), and EGFR expression. HER2 amplification was determined by fluorescent in situ hybridization. Effects of these biomarkers on event-free survival (EFS) were examined in patients with available tissue (n = 493).
Lapatinib improved median EFS in HER2-amplified, ER- or PR-positive MBC (n = 36; 5.7 v 4.5 months; P = .351); benefit was greater and statistically significant in HER2-amplified, ER-negative, PR-negative MBC (n = 42; 8.3 v 5.0 months; P = .007). In HER2-negative, ER-positive MBC, median EFS improvement varied by degree of PR expression (H-score): no benefit if PR-strong (n = 133; 9.3 v 7.3 months; P = .373), benefit if PR-weak (n = 50; 7.3 v 2.4 months; P = .026), and potential antagonism if PR-negative (n = 40; 3.7 v 7.2 months; P = .004). No benefit was seen in triple-negative MBC (n = 131; median EFS, 4.6 v 4.8 months; P = .255). EGFR expression was not correlated with benefit from lapatinib.
Although subgroups are small, these analyses support the hypothesis that semiquantitative determination of hormone receptor status may be a surrogate for EGFR and/or HER2 dependency.
The correlation between quantitative human epidermal growth factor receptor (HER)-2 protein expression in primary breast cancers and the time to brain metastases in HER-2+ advanced breast cancer patients treated with trastuzumab was investigated. A strong relationship between the quantitative HER-2 protein expression level and the risk for brain relapse in HER-2+ advanced breast cancer patients was found.
Patients with human epidermal growth factor receptor (HER)-2+ breast cancer are at particularly high risk for brain metastases; however, the biological basis is not fully understood. Using a novel HER-2 assay, we investigated the correlation between quantitative HER-2 expression in primary breast cancers and the time to brain metastasis (TTBM) in HER-2+ advanced breast cancer patients treated with trastuzumab.
The study group included 142 consecutive patients who were administered trastuzumab-based therapy for HER-2+ metastatic breast cancer. HER-2/neu gene copy number was quantified as the HER-2/centromeric probe for chromosome 17 (CEP17) ratio by central laboratory fluorescence in situ hybridization (FISH). HER-2 protein was quantified as total HER-2 protein expression (H2T) by the HERmark® assay (Monogram Biosciences, Inc., South San Francisco, CA) in formalin-fixed, paraffin-embedded tumor samples. HER-2 variables were correlated with clinical features and TTBM was measured from the initiation of trastuzumab-containing therapy.
A higher H2T level (continuous variable) was correlated with shorter TTBM, whereas HER-2 amplification by FISH and a continuous HER-2/CEP17 ratio were not predictive (p = .013, .28, and .25, respectively). In the subset of patients that was centrally determined by FISH to be HER-2+, an above-the-median H2T level was significantly associated with a shorter TTBM (hazard ratio, [HR], 2.4; p = .005), whereas this was not true for the median HER-2/CEP17 ratio by FISH (p = .4). Correlation between a continuous H2T level and TTBM was confirmed on multivariate analysis (HR, 3.3; p = .024).
These data reveal a strong relationship between the quantitative HER-2 protein expression level and the risk for brain relapse in HER-2+ advanced breast cancer patients. Consequently, quantitative assessment of HER-2 protein expression may inform and facilitate refinements in therapeutic treatment strategies for selected subpopulations of patients in this group.
Advanced breast cancer; Brain metastasis; HER-2 amplification; Quantitative HER-2 protein level; Trastuzumab
The HER2 gene has been established as a valid biological marker for the treatment of breast cancer patients with trastuzumab and probably other agents, such as paclitaxel and anthracyclines. The TOP2A gene has been associated with response to anthracyclines. Limited information exists on the relationship of HER2/TOP2A gene status in the presence of centromere 17 (CEP17) gain with outcome of patients treated with anthracycline-containing adjuvant chemotherapy.
Formalin-fixed paraffin-embedded tumor tissue samples from 1031 patients with high-risk operable breast cancer, enrolled in two consecutive phase III trials, were assessed in a central laboratory by fluorescence in situ hybridization for HER2/TOP2A gene amplification and CEP17 gain (CEP17 probe). Amplification of HER2 and TOP2A were defined as a gene/CEP17 ratio of >2.2 and ≥2.0, respectively, or gene copy number higher than 6. Additionally, HER2, TopoIIa, ER/PgR and Ki67 protein expression was assessed by immunohistochemistry (IHC) and patients were classified according to their IHC phenotype. Treatment consisted of epirubicin-based adjuvant chemotherapy followed by hormonal therapy and radiation, as indicated.
HER2 amplification was found in 23.7% of the patients and TOP2A amplification in 10.1%. In total, 41.8% of HER2-amplified tumors demonstrated TOP2A co-amplification. The median (range) of HER2, TOP2A and CEP17 gain was 2.55 (0.70-45.15), 2.20 (0.70-26.15) and 2.00 (0.70-26.55), respectively. Forty percent of the tumors had CEP17 gain (51% of those with HER2 amplification). Adjusting for treatment groups in the Cox model, HER2 amplification, TOP2A amplification, CEP17 gain and HER2/TOP2A co-amplification were not associated with time to relapse or time to death.
HER2 amplification, TOP2A amplification, CEP17 gain and HER2/TOP2A co-amplification were not associated with outcome in high-risk breast cancer patients treated with anthracycline-based adjuvant chemotherapy.
Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12611000506998 and ACTRN12609001036202
HER2; TOP2A; TopoIIa; Prognostic factors; Predictive factors; Adjuvant chemotherapy; Anthracyclines; Taxanes; Breast cancer
The EGFR and HER2 genes are located on chromosomes 7 and 17, respectively. They are therapeutic targets in some tumors. The TOP2A gene, which is located near HER2 on chromosome 17, is the target of many chemotherapeutic agents, and co-amplification of HER2 and TOP2A has been described in several tumor types. Herein, we investigated the gene status of EGFR, HER2, and TOP2A in Chinese gastric carcinoma patients. We determined the rate of polysomy for chromosomes 7 and 17, and we attempted to clarify the relationship between EGFR, HER2, and TOP2A gene copy number and increased expression of their encoded proteins. Furthermore, we tried to address the relationship between alterations in EGFR, HER2, and TOP2A and chromosome polysomy.
One hundred cases of formalin fixed and paraffin embedded tumor tissues from Chinese gastric carcinoma patients were investigated by immunohistochemistry and fluorescence in situ hybridization (FISH) methods.
Forty-two percent of the cases showed EGFR overexpression; 16% showed EGFR FISH positive; 6% showed HER2 overexpression; and 11% showed HER2 gene amplification, including all six HER2 overexpression cases. TOP2A nuclear staining (nuclear index, NI) was determined in all 100 tumors: NI values ranged from 0.5 – 90%. Three percent of the tumors showed TOP2A gene amplification, which were all accompanied by HER2 gene amplification. Nineteen percent of the tumors showed chromosome 7 polysomy, and 16% showed chromosome 17 polysomy. Chromosome 7 polysomy correlated significantly with EGFR FISH-positivity, but was not associated with EGFR overexpression. HER2 overexpression associated significantly with HER2 gene amplification. TOP2A gene amplification was significantly associated with HER2 gene amplification. No relationship was found between alterations in the EGFR, HER2, and TOP2A genes and clinicopathologic variables of gastric carcinoma.
The data from our study suggest that chromosome 7 polysomy may be responsible for increased EGFR gene copy number in gastric carcinomas, and that HER2 gene amplification may be the major reason for HER2 protein overexpression. A combined investigation of the gene status of EGFR, HER2, and TOP2A should facilitate the identification of a target therapeutic regimen for gastric carcinoma patients.
There is strong evidence demonstrating that activation of epidermal growth factor receptors (EGFRs) leads to tumor growth, progression, invasion and metastasis. Erlotinib and gefitinib, two EGFR-targeted agents, have been shown to be relevant drugs for lung cancer treatment. Recent studies demonstrate that lapatinib, a dual tyrosine kinase inhibitor of EGFR and HER-2 receptors, is clinically effective against HER-2-overexpressing metastatic breast cancer. In this report, we investigated the activity of lapatinib against non-small cell lung cancer (NSCLC).
We selected the lung cancer cell line A549, which harbors genomic amplification of EGFR and HER-2. Proliferation, cell cycle analysis, clonogenic assays, and signaling cascade analyses (by western blot) were performed in vitro. In vivo experiments with A549 cells xenotransplanted into nude mice treated with lapatinib (with or without radiotherapy) were also carried out.
Lapatinib dramatically reduced cell proliferation (P < 0.0001), DNA synthesis (P < 0.006), and colony formation capacity (P < 0.0001) in A549 cells in vitro. Furthermore, lapatinib induced G1 cell cycle arrest (P < 0.0001) and apoptotic cell death (P < 0.0006) and reduced cyclin A and B1 levels, which are regulators of S and G2/M cell cycle stages, respectively. Stimulation of apoptosis in lapatinib-treated A549 cells was correlated with increased cleaved PARP, active caspase-3, and proapoptotic Bak-1 levels, and reduction in the antiapoptic IAP-2 and Bcl-xL protein levels. We also demonstrate that lapatinib altered EGFR/HER-2 signaling pathways reducing p-EGFR, p-HER-2, p-ERK1/2, p-AKT, c-Myc and PCNA levels. In vivo experiments revealed that A549 tumor-bearing mice treated with lapatinib had significantly less active tumors (as assessed by PET analysis) (P < 0.04) and smaller in size than controls. In addition, tumors from lapatinib-treated mice showed a dramatic reduction in angiogenesis (P < 0.0001).
Overall, these data suggest that lapatinib may be a clinically useful agent for the treatment of lung cancer.
Human epidermal growth factor receptor 2 (HER2) is a therapeutic target in patients with esophageal adenocarcinoma (EAC), with gene amplification used as a selection criterion for treatment, although to the authors’ knowledge the concordance between amplification and HER2 protein expression remains undefined in EAC. Furthermore, the association between HER2 and its interacting partner, human epidermal growth factor receptor 3 (HER3), is unknown yet appears to be of potential therapeutic relevance.
Patients with untreated EACs (N 5 673) were analyzed for HER2 amplification and polysomy 17 by fluorescence in situ hybridization in parallel with immunohistochemistry (IHC) (IHC scores of 0–1+, 2+, and 3+). Amplification was defined as HER2=CEP17 ≥2. HER3 expression by IHC was analyzed in randomly selected cases (n 5 224). IHC and fluorescence in situ hybridization results were compared using least squares linear regression.
Overall, 17% of the EACs (116 of 673 EACs) were HER2-amplified with an amplification frequency that was highest among IHC3+ cases (89%) and declined among IHC2+ cases (13%) and IHCO to IHC1+ cases (4%). Among HER2-amplified cases, the level of amplification increased linearly with HER2 membranous expression (HER2/CEP17 ratio: 7.9 in IHC3+ and 5.5 in IHC2+ vs 2.8 in IHCO to IHC11 [P<.0001]), with 14% of amplified tumors demonstrating absent/faint expression (IHCO to IHC1+). Polysomy 17 was not found to be associated with HER2 expression. Cytoplasmic HER3 expression was detected in 87% of tumors (195 of 224 tumors) and was found to be significantly associated with better differentiation (P<.0001). Stepwise increases in HER3 expression were associated with higher HER2 expression levels (P = .0019).
Levels of HER2 protein expression and amplification were found to be linearly associated and highly concordant. Among amplified tumors with absent/faint expression, the level of amplification was low. Frequent expression of HER3 suggests its relevance as a therapeutic target, and its significant association with HER2 supports ongoing efforts to inhibit HER2/HER3 in patients with EAC.
human epidermal growth factor receptor 2 (HER2); ERBB2; concordance; fluorescence in situ hybridization; HER2 gene amplification; HER2 expression; HER3/ERBB3; esophageal cancer; esophageal adenocarcinoma; esophagogastric cancer
In metastatic colorectal cancer (mCRC), KRAS is the only validated biomarker used to select patients for administration of epidermal growth factor receptor (EGFR)-targeted therapies. To identify additional predictive markers, we investigated the importance of HER2, the primary EGFR dimerisation partner, in this particular disease.
We evaluated the HER2 gene status by fluorescence in situ hybridisation (FISH) in 170 KRAS wild-type mCRC patients treated with cetuximab or panitumumab.
Depending on HER2 gene copy number status, patients showed three distinct cytogenetic profiles: 4% of patients had HER2 gene amplification (R:HER2/CEP17⩾2) in all neoplastic cells (HER2-all-A), 61% of patients had HER2 gain due to polysomy or to gene amplification in minor clones (HER2-FISH+*), and 35% of patients had no or slight HER2 gain (HER2-FISH−). These subgroups were significantly correlated with different clinical behaviours, in terms of response rate (RR; P=0.0006), progression-free survival (PFS; P<0.0001) and overall survival (OS; P<0.0001). Patients with HER2-all-A profile experienced the worst outcome, patients with HER2-FISH− profile showed an intermediate behaviour and patients with HER2-FISH+* profile were related to the highest survival probability (median PFS in months: 2.5 vs 3.9 vs 7.6, respectively; median OS in months: 4.2 vs 9.7 vs 13, respectively).
HER2 gene copy number status may influence the clinical response to anti-EGFR-targeted therapy in mCRC patients.
HER2; colorectal cancer; EGFR-targeted therapy; fluorescence in situ hybridisation
There is increasing recognition of the existence of intratumoral heterogeneity of the human epidermal growth factor receptor (HER2), which affects interpretation of HER2 positivity in clinical practice and may have implications for patient prognosis and treatment. We determined the frequency and prognostic impact of heterogeneous HER2 gene amplification and polysomy 17 in patients with esophageal adenocarcinoma (EAC).
Patients and Methods
HER2 amplification (by fluorescence in situ hybridization) was examined in surgical EAC specimens (n = 675). HER2 heterogeneity was defined according to consensus guidelines as gene amplification (HER2/CEP17 ratio ≥ 2.0) in more than 5% but less than 50% of cancer cells. No patient received neoadjuvant or HER2-targeted therapy. Cox models were used to assess disease-specific survival (DSS) and overall survival (OS).
Overall, 117 EACs (17%) demonstrated HER2 amplification, of which 20 (17%) showed HER2 heterogeneity. All HER2-heterogeneous tumors were amplified. Among HER2-amplified tumors, heterogeneous tumors had significantly higher frequency of poor histologic grade and polysomy 17. In multivariable models that included number of metastatic lymph nodes, grade, tumor stage, and polysomy 17, only HER2 heterogeneity and node number were prognostic among HER2-amplified tumors, with heterogeneity showing worse DSS (hazard ratio, 2.04; 95% CI, 1.09 to 3.79; P = .025) and OS (P = .026). Among HER2-nonamplified EACs, polysomy 17 was independently associated with worse DSS (P = .012) and OS (P = .023).
Among HER2-amplified EACs, 17% show HER2 heterogeneity, which independently predicts for worse cancer-specific death. Among HER2-nonamplified EACs, polysomy 17 is independently associated with worse survival. These novel findings demonstrate aggressive subgroups in HER2-amplified and -nonamplified EACs that have important implications for HER2 analysis and determination of benefit from HER2-targeted therapy.
Patients with locally advanced breast cancer who had completed four cycles of weekly paclitaxel plus carboplatin as neoadjuvant chemotherapy were evaluated for human epidermal growth factor receptor (HER)-2 status using fluorescence in situ hybridization based on the HER-2/centromere enumerator probe (CEP)-17 ratio and based on copy number to examine differences in these two methods.
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Compare the clinical value of copy number–based fluorescence in situ hybridization (FISH) versus HER-2/CEP-17 ratio-based FISH in identifying patients who may benefit from taxane-containing neoadjuvant chemotherapy.Consider the implications of HER-2 copy number and aneusomy 17 when making treatment decisions in patients with locally advanced breast cancer.
This article is available for continuing medical education credit at CME.TheOncologist.com
Aneusomy 17 causes inconsistency in fluorescence in situ hybridization (FISH)-based human epidermal growth factor receptor (HER)-2 status assessment using different algorithms (copy number or the HER-2/centromere enumerator probe 17 [CEP-17] ratio). We investigated the effects of FISH-based HER-2 status assessment and aneusomy 17 on responsiveness to neoadjuvant chemotherapy (NAC).
Patients and Methods.
This prospective study recruited 152 patients with locally advanced breast cancer who underwent four-cycle weekly paclitaxel plus carboplatin without trastuzumab.
The pathologic complete remission (pCR) rate in the breast and axilla was 24.3% (95% confidence interval [CI], 17.7%–32.0%). Although HER-2 status, assessed by either HER-2/CEP-17 ratio–based FISH or copy number–based FISH, was a predictor of NAC sensitivity, ratio–assessed HER-2 status had a poorer performance in determining patients' responsiveness to NAC (p = .029). Patients who were not HER-2 amplified when assessed using the HER-2/CEP-17 ratio but were HER-2 amplified when assessed using copy number (∼5%) were eventually proven to be responsive to NAC, with a pCR rate of 57% (95% CI, 18.4%–90.1%). In contrast, patients who were HER-2 amplified when assessed by the ratio but not HER-2 amplified when assessed using copy number (∼3%) were completely irresponsive. Higher HER-2 copy numbers represented increasing chances of a pCR (adjusted odds ratio, 3.09; 95% CI, 1.35–7.08), with an apparent gene–dose effect (p for trend < .001).
It is likely that HER-2 copy number but not the HER-2/CEP-17 ratio determines NAC sensitivity. Additional studies to validate our findings are warranted.
Human epidermal growth factor receptor 2 (HER2) and topoisomerase II alpha (TOP2A) genes have been proposed as predictive biomarkers of sensitivity to anthracycline chemotherapy. Recently, chromosome 17 centromere enumeration probe (CEP17) duplication has also been associated with increased responsiveness to anthracyclines. However, reports are conflicting and none of these tumor markers can yet be considered a clinically reliable predictor of response to anthracyclines. We studied the association of TOP2A gene alterations, HER2 gene amplification, and CEP17 duplication with response to anthracycline-based neoadjuvant chemotherapy in 140 patients with operable or locally advanced breast cancer. HER2 was tested by fluorescence in situ hybridization and TOP2A and CEP17 by chromogenic in situ hybridization. Thirteen patients (9.3%) achieved pathologic complete response (pCR). HER2 amplification was present in 24 (17.5%) of the tumors. TOP2A amplification occurred in seven tumors (5.1%). CEP17 duplication was detected in 13 patients (9.5%). CEP17 duplication correlated with a higher rate of pCR [odds ratio (OR) 6.55, 95% confidence interval (95% CI) 1.25-34.29, P = .026], and analysis of TOP2A amplification showed a trend bordering on statistical significance (OR 6.97, 95% CI 0.96-50.12, P = .054). TOP2A amplification and CEP17 duplication combined were strongly associated with pCR (OR 6.71, 95% CI 1.66-27.01, P = .007). HER2 amplification did not correlate with pCR. Our results suggest that CEP17 duplication predicts pCR to primary anthracycline-based chemotherapy. CEP17 duplication, TOP2A amplifications, and HER2 amplifications were not associated with prognosis.
CEP17, chromosome 17 centromere enumeration probe; CI, confidence interval; CISH, chromogenic in situ hybridization; DFS, disease-free survival; EC-D, epirubicin (90 mg/m2) and cyclophosphamide (600 mg/m2) followed by docetaxel (100 mg/m2); ER, estrogen receptor; FEC75, fluorouracil (600 mg/m2), epirubicin (75 mg/m2), and cyclophosphamide (600 mg/m2); FISH, fluorescence in situ hybridization; HR, hazard ratio; HER2, human epidermal growth factor receptor 2; OR, odds ratio; OS, overall survival; pCR, pathologic complete response; PR, progesterone receptor; TOP2A, topoisomerase II alpha
We examined the frequency, tumor characteristics, and prognostic impact of HER2 protein expression and gene amplification in patients with curatively resected esophageal adenocarcinoma (EAC).
HER2 expression was analyzed by immunohistochemistry (IHC) in surgical EAC specimens (n=713). Gene amplification was examined by fluorescence in situ hybridization (FISH) in a large subset (n=344). Most tumors were T3–4 (66%) or node-positive (72%); 95% were located in the esophagus or gastroesophageal junction. No patient received neoadjuvant therapy. Cox models were used.
Overall, 17% of EACs were HER2-positive (ie, IHC3+ or IHC2+ with amplification), with strong agreement between HER2 amplification (HER2/CEP17 ratio ≥2) and expression (κ=.83). HER2-positivity was significantly associated with lower tumor grade, less invasiveness, fewer malignant nodes, and the presence of adjacent Barrett’s esophagus (BE). EACs with BE had higher odds of HER2-positivity compared to EACs without BE, independent of pathologic features (odds ratio 1.8 [95% confidence interval (CI) 1.1–2.8], p=.014). Among all cases, HER2-positivity was significantly associated with disease-specific survival (DSS) in a manner that differed by the presence or absence of BE (p for interaction=.0047). In EACs with BE, HER2-positivity was significantly associated with improved DSS (hazard ratio 0.54 [95% CI 0.35–0.84], p=.0065) and overall survival (p=.0022) independent of pathologic features, but was not prognostic among EACs without BE.
HER2-positivity was demonstrated in 17% of resected EACs and associated with reduced tumor aggressiveness. EACs with BE had nearly twice the odds of being HER2-positive and, within this subgroup, HER2-positivity was independently associated with improved survival.
esophageal adenocarcinoma; Barrett’s esophagus; HER2; ErbB2; prognosis
In non-small-cell lung cancer (NSCLC), sensitivity to tyrosine kinase inhibitors (TKIs) is associated with activating mutations and genomic gain of the epidermal growth factor receptor (EGFR). Preclinical data suggested that HER3 overexpression increases sensitivity to TKIs. A total of 82 NSCLC patients treated with gefitinib (250 mg), and previously evaluated for EGFR and HER2 status by fluorescence in situ hybridisation (FISH) and DNA sequencing, and for Phospho-Akt status by immunohistochemistry, were investigated for HER3 genomic gain by FISH. Patients with high polysomy and gene amplification were considered as HER3 FISH positive (+). HER3 FISH+ pattern was significantly associated with female gender (P=0.02) and never smoking history (P=0.02). Patients with HER3+ tumours (26.8%) had a significantly longer time to progression (3.7 vs 2.7, P=0.04) than patients with HER3− tumours, but not a significantly better response rate or survival. Patients with EGFR+/HER3+ tumours had higher objective response rate (36.4 vs 9.9%, P=0.03) and time to progression (7.7 vs 2.7 months, P=0.03) than patients with EGFR− and/or HER3− tumours, but no significantly longer survival. No difference in response was observed according to HER3 status in patients with EGFR+ tumours. Patients with HER2+/HER3+ tumours had similar outcome as patients with HER2− and/or HER3− tumours. Significantly different clinical end points were not observed between patients with HER3+/P-Akt+ and HER3− and/or P-Akt− tumours. Genomic gain for HER3 is not a marker for response or resistance to TKI therapy in advanced NSCLC patients.
HER3; EGFR; tyrosine kinase inhibitor; gefitinib; non-small-cell lung cancer
The epidermal growth factor receptor (EGFR) is a surrogate marker for basal-like breast cancer. A recent study suggested that EGFR may be used as a target for breast cancer treatment.
A total of 706 invasive ductal carcinomas (IDC) of the breast were immunophenotyped, and 82 cases with EGFR protein expression were studied for EGFR gene amplification.
EGFR protein was expressed in 121 of 706 IDCs (17.1%); 5.9% were of luminal type, 25.3% of epidermal growth factor receptor 2 (HER-2) type, and 79.3% of basal-like tumors. EGFR gene amplification and high polysomy (fluorescent in situ hybridization [FISH]-positive) were found in 18 of 82 cases (22.0%); 41.2% of the HER-2+, EGFR+, cytokeratin 5/6- (CK5/6-) group, 11.2% of the HER-2-, EGFR+, CK5/6- group, and 19.1% of the HER-2-, EGFR+, CK5/6+ group. FISH-positive cases were detected in 8.3% of the EGFR protein 1+ expression cases, 15.9% of 2+ expression cases, and 38.5% of 3+ expression cases. In group 2, the tumors had a high Ki-67 labeling (>60%), but the patients showed better disease-free survival than those with tumors that co-expressed HER-2 or CK5/6.
EGFR-directed therapy can be considered in breast cancer patients with EGFR protein overexpression and gene amplification, and its therapeutic implication should be determined in HER-2 type breast cancer patients.
Breast neoplasms; Receptor, epidermal growth factor; Gene amplification; Protein expression
Chemotherapy with trastuzumab is widely used for patients with human epidermal growth factor receptor 2-positive (HER2+) breast cancer, but a significant number of patients with the tumor fail to respond, or relapse. The mechanisms of recurrence and biomarkers that indicate the response to the chemotherapy and outcome are not fully investigated.
Genomic alterations were analyzed using single-nucleotide polymorphism arrays in 46 HER2 immunohistochemistry (IHC) 3+ or 2+/fluorescent in situ hybridization (FISH)+ breast cancers that were treated with neoadjuvant chemotherapy with paclitaxel, cyclophosphamid, epirubicin, fluorouracil, and trastuzumab. Patients were classified into two groups based on presence or absence of alterations of 65 cancer-associated genes, and the two groups were further classified into four groups based on genomic HER2 copy numbers or hormone receptor status (HR+/−). Pathological complete response (pCR) and relapse-free survival (RFS) rates were compared between any two of the groups.
Results and discussion
The pCR rate was 54% in 37 patients, and the RFS rate at 3 years was 72% (95% CI, 0.55-0.89) in 42 patients. The analysis disclosed 8 tumors with nonamplified HER2 and 38 tumors with HER2 amplification, indicating the presence of discordance in tumors diagnosed using current HER2 testing. The 8 patients showed more difficulty in achieving pCR (P=0.019), more frequent relapse (P=0.018), and more frequent alterations of genes in the PI3K pathway (P=0.009) than the patients with HER2 amplification. The alterations of the PI3K and estrogen receptor (ER) pathway genes generally indicated worse RFS rates. The prognostic significance of the alterations was shown in patients with a HR+ tumor, but not in patients with a HR- tumor when divided. Alterations of the PI3K and ER pathway genes found in patients with a HR+ tumor with poor outcome suggested that crosstalk between the two pathways may be involved in resistance to the current chemotherapy with trastuzumab.
We recommend FISH analysis as a primary HER2 testing because patients with IHC 2+/3+ and nonamplified HER2 had poor outcome. We also support concurrent use of trastuzumab, lapatinib, and cytotoxic and anti-hormonal agents for patients having HR+ tumors with alterations of the PI3K and ER pathway genes.
HER2; SNP array; Trastuzumab; Neoadjuvant chemotherapy; PI3K pathway; Estrogen receptor pathway; Complete pathological response; Relapse-free survival
TRIBUTE was a phase III trial evaluating the addition of erlotinib to carboplatin and paclitaxel as a first-line treatment for advanced non – small cell lung cancer that did not meet its primary end point of improving overall survival. Here, we assess the value of using epidermal growth factor receptor (EGFR) gene copy number in tumor biopsy samples, as determined by fluorescence in situ hybridization (FISH), as a predictor of treatment outcome.
EGFR FISH analysis was done using LSI EGFR SpectrumOrange/CEP7 Spectrum-Green probe.
Of 275 samples, 245 (89.1%) were successfully analyzed by FISH. One hundred (40.8%) of patients were EGFR FISH(+). Median overall survival was not different between FISH(+) and FISH(−) patients in either the chemotherapy+erlotinib arm or the chemotherapy+placebo arm. In FISH(+) patients, median time to progression (TTP) was 6.3 months in the erlotinib arm versus 5.8 months in the placebo arm (hazard ratio, 0.59; 95% confidence interval, 0.35–0.99; P = 0.0430); in FISH(−) patients, median TTP was 4.6 months versus 6.0 months (hazard ratio,1.42; 95%confidence interval, 0.95–2.14; P = 0.0895; treatment interaction test, P = 0.007). After 6 months of treatment, a notable separation of the TTP curves in favor of erlotinib emerged. Objective response rates were11.6% versus 29.8% in FISH(+) patients (chemotherapy+erlotinib arm versus chemotherapy+placebo arm; P = 0.0495) and 21.8% versus 25.4%, respectively, for FISH(−) patients (P = 0.6954).
EGFR gene copy number by FISH did not predict survival benefit. However, among EGFR FISH(+) patients, TTP was longer in patients who received erlotinib and continued to receive it after completing first-line therapy.
To determine whether lapatinib, a dual epidermal growth factor receptor (EGFR)/HER2 kinase inhibitor, can radiosensitize EGFR+ or HER2+ breast cancer xenografts.
Methods and Materials
Mice bearing xenografts of basal-like/EGFR+ SUM149 and HER2+ SUM225 breast cancer cells were treated with lapatinib and fractionated radiotherapy and tumor growth inhibition correlated with alterations in ERK1 and AKT activation by immunohistochemistry.
Basal-like/EGFR+ SUM149 breast cancer tumors were completely resistant to treatment with lapatinib alone but highly growth impaired with lapatinib plus radiotherapy, exhibiting an enhancement ratio average of 2.75 and a fractional tumor product ratio average of 2.20 during the study period. In contrast, HER2+ SUM225 breast cancer tumors were highly responsive to treatment with lapatinib alone and yielded a relatively lower enhancement ratio average of 1.25 during the study period with lapatinib plus radiotherapy. Durable tumor control in the HER2+ SUM225 model was more effective with the combination treatment than either lapatinib or radiotherapy alone. Immunohistochemical analyses demonstrated that radiosensitization by lapatinib correlated with ERK1/2 inhibition in the EGFR+ SUM149 model and with AKT inhibition in the HER2+ SUM225 model.
Our data suggest that lapatinib combined with fractionated radiotherapy may be useful against EGFR+ and HER2+ breast cancers and that inhibition of downstream signaling to ERK1/2 and AKT correlates with sensitization in EGFR+ and HER2+ cells, respectively.
Breast cancer; epidermal growth factor receptor; HER2; radiosensitization; lapatinib
Human epidermal growth factor receptor (HER)-2 overexpression or gene amplification is more common in high-grade or type 2 endometrial carcinomas. We assessed the discordance of HER-2 expression between primary and metastatic or recurrent endometrial carcinomas.
Materials and methods
Thirty-six primary, along with 14 metastatic and five recurrent tumors (matched to primaries), pathologically confirmed as high-grade or type 2 endometrial carcinomas, were submitted for immunohistochemistry (IHC) for HER-2. Fluorescence in situ hybridization was performed when the tumors showed HER-2 overexpression (≥2+ IHC score). The results of the IHC and fluorescence in situ hybridization assays were compared between the primary and metastatic or recurrent tumors. The relationships between HER-2 expression and clinicopathological factors or prognosis were investigated.
HER-2 overexpression and HER-2 amplification (a ratio of HER-2 copies to chromosome 17 [CEP17] copies ≥2.2) were detected in 33.3% (twelve of 36 patients) and 5.6% (two of 36 patients) of primary tumors, respectively. HER-2 overexpression was not associated with clinicopathological factors or prognosis. In 19 tumor specimens obtained from metastatic or recurrent tumors, HER-2 overexpression and HER-2 amplification were detected in 57.9% (eleven patients) and 15.8% (three patients), respectively. HER-2 overexpression tended to predict a worse prognosis.
HER-2 expression in metastatic or recurrent tumors was more frequent than in matched primary high-grade or type 2 endometrial carcinomas. Trastuzumab in combination with cytotoxic chemotherapy may represent an alternative therapeutic option for these tumors.
endometrial carcinoma; high grade; type 2; HER-2; metastatic or recurrent tumors
The HER (human EGFR related) family of receptor tyrosine kinases (HER1/EGFR (epidermal growth factor receptor)/c-erbB1, HER2/c-erbB2, HER3/c-erbB3 and HER4/c-erbB4) shares a high degree of structural and functional homology. It constitutes a complex network, coupling various extracellular ligands to intracellular signal transduction pathways resulting in receptor interaction and cross-activation. The most famous family member is HER2, which is a target in Herceptin™ therapy in metastatic status and also in adjuvant therapy of breast cancer in the event of dysregulation as a result of gene amplification and resulting protein overexpression. The HER2-related HER receptors have been shown to interact directly with HER2 receptors and thereby mutually affect their activity and subsequent malignant growth potential. However, the clinical outcome with regard to total HER receptor state remains largely unknown.
We investigated HER1–HER4, at both the DNA and the protein level, using fluorescence in situ hybridisation (FISH) probes targeted to all four receptor loci and also immunohistochemistry in tissue microarrays derived from 278 breast cancer patients.
We retrospectively found HER3 gene amplification with a univariate negative impact on disease-free survival (hazard ratio 2.35, 95% confidence interval 1.08 to 5.11, p = 0.031), whereas HER4 amplification showed a positive trend in overall and disease-free survival. Protein expression revealed no additional information.
Overall, the simultaneous quantification of HER3 and HER4 receptor genes by means of FISH might enable the rendering of a more precise stratification of breast cancer patients by providing additional prognostic information. The continuation of explorative and prospective studies on all HER receptors will be required for an evaluation of their potential use for specific therapeutic targeting with respect to individualised therapy.
Salivary duct carcinomas (SDCs) and adenoid cystic carcinomas (ACCs) are the most aggressive and the most frequent carcinomas of the salivary glands, respectively. Little is known about them in terms of molecular/biochemical characterization and conventional treatments are ineffective. On cryopreserved material, we analyzed the expression/activation status of TRK-A, HER-2/neu, and KIT receptors by means of immunoprecipitation and Western blot analysis experiments, and the presence of their cognate ligands by means of Western blot analysis and/or reverse transcription-polymerase chain reaction in 9 SDCs, 12 ACCs, and 8 normal glands. The amplification status of HER-2/neu was also investigated by means of fluorescent in situ hybridization analysis on fixed material. The receptor tyrosine kinase (RTK)-deregulated profile of the SDCs was characterized by the overexpression of activated TRK-A in the presence of its ligand, and the overexpression of HER-2/neu sustained by gene amplification. The RTK signature of the ACCs was represented by the overexpression of activated KIT and TRK-A and their cognate ligands, and the overexpression of activated HER-2/neu, in the absence of gene amplification, possibly sustained by epidermal growth factor receptor heterodimerization. In conclusion, SDCs and ACCs, although sharing TRK-A autocrine loop activation, have different pathologically activated RTK-deregulated profiles that may be potential targets for pharmacological RTK inhibitors.
Human epidermal growth factor receptor 2 (HER2) amplification and overexpression are associated with poor prognosis and resistance to cytotoxic drugs in patients with breast cancer. Increases in the number of HER2 gene copies have been shown to be associated with chromosome 17 polysomy. The use of whole, intact nuclei for fluorescence in situ hybridization (FISH) assay improves the accuracy of the results. FISH analysis of whole nuclei (WNFISH) and immunohistochemistry (IHC) were used to analyze HER2 gene amplification and HER2 protein expression in 109 breast cancer specimens. Chromosome 17 polysomy and its correlations with HER2 gene amplification, HER2 protein expression and the clinicopathological outcomes of the patients were also investigated. Among the 109 cases, WNFISH detected HER2 amplification in 30 cases, equivocal amplification in 19 cases and no amplification in 60 cases. WNFISH detected chromosome 17 centromere (CEP17) polysomy in 37 cases and no polysomy in 72 cases. Among the 109 cases assessed by tissue microarray and IHC, 31 cases were HER2-negative, 14 cases were scored 1+, 23 cases were scored 2+ and 41 cases were scored 3+. The results demonstrated that in the cases with chromosome 17 polysomy, the HER2 gene was amplified, HER2 protein expression was increased and the incidences of nuclear atypia and lymph node metastases were higher compared with those in the cases without chromosome 17 polysomy. Chromosome 17 polysomy may correlate with increased malignant potential and metastatic spread in breast cancer.
breast cancer; nuclei microarray; fluorescence in situ hybridization; HER2 gene
Gefitinib, a small molecule tyrosine kinase inhibitor of the Epidermal Growth Factor Receptor (EGFR), has shown limited efficacy in the treatment of lung cancer. Recognized clinical predictors of response to this drug, specifically female, non-smoker, Asian descent, and adenocarcinoma, together suggest a genetic basis for drug response. Recent studies have addressed the relationship between response and either sequence mutations or increased copy number of specific receptor tyrosine kinases. We set out to examine the relationship between response and the molecular status of two such kinases, EGFR and HER2, in 39 patients treated with gefitinib at the BC Cancer Agency.
Archival patient material was reviewed by a pathologist and malignant cells were selectively isolated by laser microdissection or manual recovery of cells from microscope slides. Genomic DNA was extracted from 37 such patient samples and exons 18–24, coding for the tyrosine kinase domain of EGFR, were amplified by PCR and sequenced. EGFR and HER2 copy number status were also assessed using FISH in 26 samples. Correlations between molecular features and drug response were assessed using the two-sided Fisher's exact test.
Mutations previously correlated with response were detected in five tumours, four with exon 19 deletions and one with an exon 21 missense L858R point mutation. Increased gene copy number was observed in thirteen tumours, seven with EGFR amplification, three with HER2 amplification, and three with amplification of both genes. In our study cohort, a correlation was not observed between response and EGFR mutations (exon 19 deletion p = 0.0889, we observed a single exon 21 mutation in a non-responder) or increases in EGFR or HER2 copy number (p = 0.552 and 0.437, respectively).
Neither mutation of EGFR nor increased copy number of EGFR or HER2 was diagnostic of response to gefitinib in this cohort. However, validation of these features in a larger sample set is appropriate. Identification of additional predictive biomarkers beyond EGFR status may be necessary to accurately predict treatment outcome.
Human epidermal growth factor receptor 2 (HER2)-amplified breast cancers represent a tumor subtype with chromosome 17q rearrangements that lead to frequent gene amplifications. The aim of this study was to quantify the amplification of genes located on chromosome 17q and to analyze the relations between the pattern of gene amplifications and the patients' characteristics and survival.
Patients with HER2-positive breast tumors (HER2 score of 3+ by immunohistochemistry or positive for HER2 amplification by fluorescence in situ hybridization (FISH)) (n = 86) and with HER2-negative breast tumors (n = 40) (negative controls) were included in this study. Using a quantitative polymerase chain reaction method and DNA extracted from frozen tumor specimens, 11 genes (MED1, STARD3, HER2, GRB7, THRA, RARA, TOP2A, IGFBP4, CCR7, KRT20, KRT19 and GAS), which are localized within Chr17q12-q21 and have a putative role in breast cancer development, were quantified. Relapse-free and overall survival rates were estimated from the date of surgery to the date of the event of interest (recurrence or death) using the Kaplan-Meier method.
Gene amplification was observed only in HER2-positive tumors, and the frequency of amplification decreased with the distance of the gene from HER2. HER2 presented the highest level of amplification. TOP2A was not included in the smallest region of amplification involving HER2. Amplification of RARA, KRT20 and KRT19 was significantly associated with node-positive breast cancer (P = 0.030, P = 0.002 and P = 0.033, respectively). During a median follow-up period of 55 months (range, 6 to 81 months), the subgroup of patients with hormone receptor-negative cancer and without TOP2A amplification showed the worst survival (relapse-free survival: hazard ratio (HR) = 0.29, 95% confidence interval (95% CI), 0.13 to 0.65, P = 0.001; and overall survival: HR = 0.28, 95% CI, 0.10 to 0.76, P = 0.008).
HER2 amplification seems to drive genomic instability along chromosome 17q, leading to different patterns of gene amplification. This study confirms the clinical importance of identifying, among patients with HER2-positive breast tumors, the subgroup of patients with hormone receptor-negative and nonamplified TOP2A cancers as they have the worst prognosis.