Clinical characteristics of ovarian cancer classified by BRCA1, BRCA2, and RAD51C status.

We evaluated homologous recombination deficient (HRD) phenotypes in epithelial ovarian cancer (EOC) considering BRCA1, BRCA2, and RAD51C in a large well-annotated patient set. We evaluated EOC patients for germline deleterious mutations (n = 899), somatic mutations (n = 279) and epigenetic alterations (n = 482) in these genes using NGS and genome-wide methylation arrays. Deleterious germline mutations were identified in 32 (3.6%) patients for BRCA1, in 28 (3.1%) for BRCA2 and in 26 (2.9%) for RAD51C. Ten somatically sequenced patients had deleterious alterations, six (2.1%) in BRCA1 and four (1.4%) in BRCA2. Fifty two patients (10.8%) had methylated BRCA1 or RAD51C. HRD patients with germline or somatic alterations in any gene were more likely to be high grade serous, have an earlier diagnosis age and have ovarian and/or breast cancer family history. The HRD phenotype was most common in high grade serous EOC. Identification of EOC patients with an HRD phenotype may help tailor specific therapies.This work was supported by National Institutes of Health grants R01-CA122443, P50-CA136393, P30-CA15083, and the Fred C. and Katherine B. Andersen Foundation. We thank Gary Kenney, M.D. for pathology review of tumor tissue. We thank Craig Luccarini, Caroline Baynes from University of Cambridge for assisting our sample sequencing

Activity of lapatinib a novel HER2 and EGFR dual kinase inhibitor in human endometrial cancer cells

In this study, we explore the therapeutic potential of lapatinib a selective inhibitor of both the EGFR and HER2 tyrosine kinases for the treatment of endometrial cancer. The effect of lapatinib on tumour cell growth and receptor activation was studied in a panel of human endometrial cancer cell lines. Candidate molecular markers predicting sensitivity were assessed by baseline gene expression profiling, ELISA, and western blot analyses. Multiple drug effect/combination index (CI) isobologram analysis was used to study the interactions between chemotherapeutic drugs and lapatinib. Concentration-dependent anti-proliferative effects of lapatinib were seen in all endometrial cancer cell lines tested, but varied significantly between individual cell lines (IC50 range: 0.052–10.9 μmol). HER2 overexpression or increased expression of EGFR was significantly associated with in vitro sensitivity (P=0.024 or 0.011, respectively). Lapatinib exerts growth inhibition in a PTEN-independent manner. Sensitive cell lines also exhibited increased expression of EGFR ligands or HER3. In contrast, lapatinib-resistant cell lines exhibited high androgen receptor (AR) levels or epithelial-to-mesenchymal transition (post-EMT) features. In endometrial cancer cells, at a wide range of clinically achievable drug concentrations, additive and synergistic interactions were observed for lapatinib plus carboplatin, paclitaxel, docetaxel, and doxorubicin. These observations provide a clear biologic rational to test lapatinib as a single agent or in combination with chemotherapy in endometrial cancer with HER2 overexpression. Expression of EGFR, its ligands, HER3, AR, and post-EMT markers warrant further evaluation to help define patients with HER2-nonoverexpressing endometrial cancer most likely to benefit from lapatinib

HER2 gene amplification and EGFR expression in a large cohort of surgically staged patients with nonendometrioid (type II) endometrial cancer

Type II endometrial cancers (uterine serous papillary and clear cell histologies) represent rare but highly aggressive variants of endometrial cancer (EC). HER2 and EGFR may be differentially expressed in type II EC. Here, we evaluate the clinical role of HER2 and EGFR in a large cohort of surgically staged patients with type II (nonendometrioid) EC and compare the findings with those seen in a representative cohort of type I (endometrioid) EC. In this study HER2 gene amplification was studied by fluorescence in situ hybridisation (FISH) and EGFR expression by immunohistochemistry. Tissue microarrays were constructed from 279 patients with EC (145 patients with type I and 134 patients with type II EC). All patients were completely surgically staged and long-term clinical follow up was available for 258 patients. The rate of HER2 gene amplification was significantly higher in type II EC compared with type I EC (17 vs 1%, P<0.001). HER2 gene amplification was detected in 17 and 16% of the cases with uterine serous papillary and clear cell type histology, respectively. In contrast, EGFR expression was significantly lower in type II compared with type I EC (34 vs 46%, P=0.041). EGFR expression but not HER2 gene amplification was significantly associated with poor overall survival in patients with type II EC, (EGFR, median survival 20 vs 33 months, P=0.028; HER2, median survival 18 vs 29 months, P=0.113) and EGFR expression retained prognostic independence when adjusting for histology, stage, grade, and age (EGFR, P=0.0197; HER2, P=0.7855). We conclude that assessment of HER2 gene amplification and/or EGFR expression may help to select type II EC patients who could benefit from therapeutic strategies targeting both HER2 and EGFR

Targeting EGFR/HER2 pathways enhances the antiproliferative effect of gemcitabine in biliary tract and gallbladder carcinomas

<p>Abstract</p> <p>Background</p> <p>Advanced biliary tract carcinomas (BTCs) have poor prognosis and limited therapeutic options. Therefore, it is crucial to combine standard therapies with molecular targeting. In this study EGFR, HER2, and their molecular transducers were analysed in terms of mutations, amplifications and over-expression in a BTC case series. Furthermore, we tested the efficacy of drugs targeting these molecules, as single agents or in combination with gemcitabine, the standard therapeutic agent against BTC.</p> <p>Methods</p> <p>Immunohistochemistry, FISH and mutational analysis were performed on 49 BTC samples of intrahepatic (ICCs), extrahepatic (ECCs), and gallbladder (GBCs) origin. The effect on cell proliferation of different EGFR/HER2 pathway inhibitors as single agents or in combination with gemcitabine was investigated on BTC cell lines. Western blot analyses were performed to investigate molecular mechanisms of targeted drugs.</p> <p>Results</p> <p>EGFR is expressed in 100% of ICCs, 52.6% of ECCs, and in 38.5% of GBCs. P-MAPK and p-Akt are highly expressed in ICCs (>58% of samples), and to a lower extent in ECCs and GBCs (<46%), indicating EGFR pathway activation. HER2 is overexpressed in 10% of GBCs (with genomic amplification), and 26.3% of ECCs (half of which has genomic amplification). EGFR or its signal transducers are mutated in 26.5% of cases: 4 samples bear mutations of PI3K (8.2%), 3 cases (6.1%) in K-RAS, 4 (8.2%) in B-RAF, and 2 cases (4.1%) in PTEN, but no loss of PTEN expression is detected. EGI-1 cell line is highly sensitive to gemcitabine, TFK1 and TGBC1-TKB cell lines are responsive and HuH28 cell line is resistant. In EGI-1 cells, combination with gefitinib further increases the antiproliferative effect of gemcitabine. In TFK1 and TGBC1-TKB cells, the efficacy of gemcitabine is increased with addiction of sorafenib and everolimus. In TGBC1-TKB cells, lapatinib also has a synergic effect with gemcitabine. HuH28 becomes responsive if treated in combination with erlotinib. Moreover, HuH28 cells are sensitive to lapatinib as a single agent. Molecular mechanisms were confirmed by western blot analysis.</p> <p>Conclusion</p> <p>These data demonstrate that EGFR and HER2 pathways are suitable therapeutic targets for BTCs. The combination of gemcitabine with drugs targeting these pathways gives encouraging results and further clinical studies could be warranted.</p

Molecular and clinical determinants of response and resistance to rucaparib for recurrent ovarian cancer treatment in ARIEL2 (Parts 1 and 2)

ARIEL2 (NCT01891344) is a single-arm, open-label phase 2 study of the PARP inhibitor (PARPi) rucaparib in relapsed high-grade ovarian carcinoma. In this post hoc exploratory biomarker analysis of pre- and post-platinum ARIEL2 samples, RAD51C and RAD51D mutations and high-level BRCA1 promoter methylation predict response to rucaparib, similar to BRCA1/BRCA2 mutations. BRCA1 methylation loss may be a major cross-resistance mechanism to platinum and PARPi. Genomic scars associated with homologous recombination deficiency are irreversible, persisting even as platinum resistance develops, and therefore are predictive of rucaparib response only in platinum-sensitive disease. The RAS, AKT, and cell cycle pathways may be additional modulators of PARPi sensitivity

Beyond trastuzumab: novel therapeutic strategies in HER2-positive metastatic breast cancer

The use of trastuzumab, a monoclonal antibody that targets the human epidermal growth factor receptor 2 (HER2) alteration present in 25 to 30% of breast cancers, has been associated with improved survival outcomes in both the adjuvant and metastatic settings. However, despite the robust clinical efficacy of trastuzumab in HER2-positive metastatic breast cancer (MBC), primary and secondary resistance remains a clinical challenge. Although lapatinib has demonstrated modest activity in this setting, trials reported to date have yet to demonstrate improvements in overall survival with its use. Novel therapeutic strategies to circumvent trastuzumab resistance are warranted, and agents targeting the HER, vascular endothelial growth factor, heat shock protein 90, phosphoinositide 3 kinase/Akt/mammalian target of rapamycin, and insulin-like growth factor-1 receptor pathways represent rational approaches in the management of HER2-positive disease. In this review, early-phase and emerging trial data surrounding the use of these promising agents in HER2-positive MBC will be discussed

Clinical response after two cycles compared to HER2, Ki-67, p53, and bcl-2 in independently predicting a pathological complete response after preoperative chemotherapy in patients with operable carcinoma of the breast

Introduction To investigate the predictive value of clinical and biological markers for a pathological complete remission after a preoperative dose-dense regimen of doxorubicin and docetaxel, with or without tamoxifen, in primary operable breast cancer. Methods Patients with a histologically confirmed diagnosis of previously untreated, operable, and measurable primary breast cancer (tumour (T), nodes (N) and metastases (M) score: T2-3(>= 3 cm) N0-2 M0) were treated in a prospectively randomised trial with four cycles of dose-dense (bi-weekly) doxorubicin and docetaxel (ddAT) chemotherapy, with or without tamoxifen, prior to surgery. Clinical and pathological parameters (menopausal status, clinical tumour size and nodal status, grade, and clinical response after two cycles) and a panel of biomarkers (oestrogen and progesterone receptors, Ki-67, human epidermal growth factor receptor 2 (HER2), p53, bcl-2, all detected by immunohistochemistry) were correlated with the detection of a pathological complete response (pCR). Results A pCR was observed in 9.7% in 248 patients randomised in the study and in 8.6% in the subset of 196 patients with available tumour tissue. Clinically negative axillary lymph nodes, poor tumour differentiation, negative oestrogen receptor status, negative progesterone receptor status, and loss of bcl-2 were significantly predictive for a pCR in a univariate logistic regression model, whereas in a multivariate analysis only the clinical nodal status and hormonal receptor status provided significantly independent information. Backward stepwise logistic regression revealed a response after two cycles, with hormone receptor status and lymph-node status as significant predictors. Patients with a low percentage of cells stained positive for Ki-67 showed a better response when treated with tamoxifen, whereas patients with a high percentage of Ki-67 positive cells did not have an additional benefit when treated with tamoxifen. Tumours overexpressing HER2 showed a similar response to that in HER2-negative patients when treated without tamoxifen, but when HER2-positive tumours were treated with tamoxifen, no pCR was observed. Conclusion Reliable prediction of a pathological complete response after preoperative chemotherapy is not possible with clinical and biological factors routinely determined before start of treatment. The response after two cycles of chemotherapy is a strong but dependent predictor. The only independent factor in this subset of patients was bcl-2. Trial registration number NCT0054382

Trastuzumab-DM1 causes tumour growth inhibition by mitotic catastrophe in trastuzumab-resistant breast cancer cells in vivo

Introduction Trastuzumab is widely used for the treatment of HER2-positive breast cancer. Despite encouraging clinical results, a significant fraction of patients are, or become, refractory to the drug. To overcome this, trastuzumab-DM1 (T-DM1), a newer, more potent drug has been introduced. We tested the efficacy and mechanisms of action of T-DM1 in nine HER2-positive breast cancer cell lines in vitro and in vivo. The nine cell lines studied included UACC-893, MDA-453 and JIMT-1, which are resistant to both trastuzumab and lapatinib. Methods AlamarBlue cell-proliferation assay was used to determine the growth response of breast cancer cell lines to trastuzumab and T-DM1 in vitro. Trastuzumab- and T-DM1-mediated antibody-dependent cellular cytotoxicity (ADCC) was analysed by measuring the lactate dehydrogenase released from the cancer cells as a result of ADCC activity of peripheral blood mononuclear cells. Severe Combined Immunodeficient (SCID) mice were inoculated with trastuzumab-resistant JIMT-1 cells to investigate the tumour inhibitory effect of T-DM1 in vivo. The xenograft samples were investigated using histology and immunohistochemistry. Results T-DM1 was strongly growth inhibitory on all investigated HER2-positive breast cancer cell lines in vitro. T-DM1 also evoked antibody-dependent cellular cytotoxicity (ADCC) similar to that of trastuzumab. Outgrowth of JIMT-1 xenograft tumours in SCID mice was significantly inhibited by T-DM1. Histologically, the cellular response to T-DM1 consisted of apoptosis and mitotic catastrophe, the latter evidenced by an increased number of cells with aberrant mitotic figures and giant multinucleated cells. Conclusions Our results suggest mitotic catastrophe as a previously undescribed mechanism of action of T-DM1. T-DM1 was found effective even on breast cancer cell lines with moderate HER2 expression levels and cross-resistance to trastuzumab and lapatinib (MDA-453 and JIMT-1).BioMed Central Open acces

Antitumor and antiangiogenic effect of the dual EGFR and HER-2 tyrosine kinase inhibitor lapatinib in a lung cancer model

<p>Abstract</p> <p>Background</p> <p>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).</p> <p>Methods</p> <p>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 <it>in vitro</it>. <it>In vivo </it>experiments with A549 cells xenotransplanted into nude mice treated with lapatinib (with or without radiotherapy) were also carried out.</p> <p>Results</p> <p>Lapatinib dramatically reduced cell proliferation (<it>P </it>< 0.0001), DNA synthesis (<it>P </it>< 0.006), and colony formation capacity (<it>P </it>< 0.0001) in A549 cells <it>in vitro</it>. Furthermore, lapatinib induced G1 cell cycle arrest (<it>P </it>< 0.0001) and apoptotic cell death (<it>P </it>< 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. <it>In vivo </it>experiments revealed that A549 tumor-bearing mice treated with lapatinib had significantly less active tumors (as assessed by PET analysis) (<it>P </it>< 0.04) and smaller in size than controls. In addition, tumors from lapatinib-treated mice showed a dramatic reduction in angiogenesis (<it>P </it>< 0.0001).</p> <p>Conclusion</p> <p>Overall, these data suggest that lapatinib may be a clinically useful agent for the treatment of lung cancer.</p