[Strategies to Overcome Acquired Resistance to EGFR-TKI Therapy Based on T790M Specific Substances using Osimertinib as an Example]. / Strategien zur Überwindung der erworbenen EGFR-TKI-Resistenz durch T790M spezifische Substanzen am Beispiel von Osimertinib.

Tyrosine kinase inhibitors (TKIs) of the epidermal growth factor receptor (EGFR) are widely used in non-small cell lung cancer patients harboring activating EGFR mutations. However, resistance mechanisms, particularly the T790 M mutation, hamper longer-term therapeutic success of first and second generation EGFR-TKIs. To address this unmet medical need, EGFR-TKIs of the third generation are under clinical development. Relevant clinical efficacy with mainly mild to moderate class-specific side effects has been shown for third-generation EGFR-TKIs. Molecular testing is of major importance in deciding for treatment with third generation EGFR-TKIs. This article elucidates the developmental state of third generation EGFR-TKIs with its focus on Osimertinib, the first and currently the only compound in this class which is approved in Germany. Additionally, the medical importance of molecular diagnosis using tumor tissue and circulating tumor DNA is discussed.

PD-L1 protein expression assessed by immunohistochemistry is neither prognostic nor predictive of benefit from adjuvant chemotherapy in resected non-small cell lung cancer.

Background: The expression of programmed death (PD) ligand 1 (PD-L1) protein expression assessed by immunohistochemistry (IHC) has been correlated with response and survival benefit from anti-PD-1/PD-L1 immune checkpoint inhibitor therapies in advanced non-small cell lung carcinoma (NSCLC). The efficacy of several agents appears correlated with PD-L1 expression. It remains controversial whether PD-L1 is prognostic in NSCLC. We assessed the prognostic value of PD-L1 IHC and its predictive role for adjuvant chemotherapy in early stage NSCLC. Patients and methods: Tumor sections from three pivotal adjuvant chemotherapy trials (IALT, JBR.10, CALGB 9633) using the E1L3N antibody were studied in this pooled analysis. PD-L1 staining intensity and percentage in both tumor cells (TCs) and immune cells (ICs) were scored by two pathologists. The average or consensus PD-L1 expression levels across intensities and/or percent cells stained were correlated with clinicopathological and molecular features, patient survivals and potential benefit of adjuvant chemotherapy. Results: Results from 982 patients were available for analysis. Considering staining at any intensities for overall PD-L1 expression, 314 (32.0%), 204 (20.8%) and 141 (14.3%) tumor samples were positive for PD-L1 staining on TCs using cut-offs at ≥1%, ≥10% and ≥25%, respectively. For PD-L1 expressing ICs, 380 (38.7%), 308 (31.4%) and 148 (15.1%) were positive at ≥ 1%, ≥10% and 25% cut-offs, respectively. Positive PD-L1 was correlated with squamous histology, intense lymphocytic infiltrate, and KRAS but not with TP53 mutation. EGFR mutated tumors showed statistically non-significant lower PD-L1 expression. PD-L1 expression was neither prognostic with these cut-offs nor other exploratory cut-offs, nor were predictive for survival benefit from adjuvant chemotherapy. Conclusions: PD-L1 IHC is not a prognostic factor in early stage NSCLC patients. It is also not predictive for adjuvant chemotherapy benefit in these patients.

Interleukin levels and their potential association with venous thromboembolism and survival in cancer patients.

Cytokines have been found to be elevated in cancer patients and have been associated with worse prognosis in single tumour entities. We investigated the association of eight different cytokines with venous thromboembolism (VTE) and prognosis in cancer patients. The Vienna Cancer and Thrombosis Study (CATS), a prospective study, includes patients with newly diagnosed tumour or disease progression. Patients with an overt infection are excluded. Study end-points are VTE, death, loss to follow-up or study completion. Interleukin (IL) serum levels were measured using the xMAP technology developed by Luminex. Among 726 included patients, no associations between IL levels and VTE were found, with the exception of a trend for IL-1ß and IL-6 in pancreatic cancer. Elevated levels of IL-6 [as continuous variable per double increase hazard ratio (HR) = 1·07, 95% confidence interval (CI) = 1·027-1·114, P = 0·001, IL-8 (HR = 1·12, 95% CI = 1·062-1·170, P < 0·001) and IL-11 (HR = 1·37, 95% CI = 1·103-1·709, P = 0·005] were associated with worse survival. In subgroup analyses based on tumour type, colon carcinoma patients, who had higher IL-6 levels, showed a shorter survival (HR = 2·405, 95% CI = 1·252-4·618, P = 0·008). A significant association of elevated IL-10 levels with a decrease in survival (HR = 1·824, 95% CI = 1·098-3·031, P = 0·020) was seen among patients with lung cancer. No correlation between VTE and IL levels was found, but higher IL-6, IL-8 and IL-11 levels were associated with worse survival in cancer patients. Further, elevated IL-6 levels might be a prognostic marker in colorectal cancer and elevated IL-10 levels in lung cancer patients.

Third CECOG consensus on the systemic treatment of non-small-cell lung cancer.

The current third consensus on the systemic treatment of non-small-cell lung cancer (NSCLC) builds upon and updates similar publications on the subject by the Central European Cooperative Oncology Group (CECOG), which has published such consensus statements in the years 2002 and 2005 (Zielinski CC, Beinert T, Crawford J et al. Consensus on medical treatment of non-small-cell lung cancer--update 2004. Lung Cancer 2005; 50: 129-137). The principle of all CECOG consensus is such that evidence-based recommendations for state-of-the-art treatment are given upon which all participants and authors of the manuscript have to agree (Beslija S, Bonneterre J, Burstein HJ et al. Third consensus on medical treatment of metastatic breast cancer. Ann Oncol 2009; 20 (11): 1771-1785). This is of particular importance in diseases in which treatment options depend on very particular clinical and biologic variables (Zielinski CC, Beinert T, Crawford J et al. Consensus on medical treatment of non-small-cell lung cancer--update 2004. Lung Cancer 2005; 50: 129-137; Beslija S, Bonneterre J, Burstein HJ et al. Third consensus on medical treatment of metastatic breast cancer. Ann Oncol 2009; 20 (11): 1771-1785). Since the publication of the last CECOG consensus on the medical treatment of NSCLC, a series of diagnostic tools for the characterization of biomarkers for personalized therapy for NSCLC as well as therapeutic options including adjuvant treatment, targeted therapy, and maintenance treatment have emerged and strongly influenced the field. Thus, the present third consensus was generated that not only readdresses previous disease-related issues but also expands toward recent developments in the management of NSCLC. It is the aim of the present consensus to summarize minimal quality-oriented requirements for individual patients with NSCLC in its various stages based upon levels of evidence in the light of a rapidly expanding array of individual therapeutic options.

Cisplatin benefit is predicted by immunohistochemical analysis of DNA repair proteins in squamous cell carcinoma but not adenocarcinoma: theranostic modeling by NSCLC constituent histological subclasses.

BACKGROUND: Most non-small-cell lung cancer (NSCLC) patients receive cisplatin-based chemotherapy though clinical response is restricted to a subset of patients. DNA repair protein levels are possible surrogates for cisplatin-induced DNA adduct (and subsequent cell death) repair efficiency and thus molecular determinants of therapeutic efficacy. The International Adjuvant Lung Trial (IALT)-Bio study previously suggested ERCC1 and MSH2 as predictive of cisplatin-based therapeutic benefit. PATIENTS AND METHODS: DNA repair protein expression (XPF, BRCA1, ERCC1, MSH2, p53, PARP1, and ATM) was assessed by immunohistochemistry on a large subset of patients (N = 769) from the IALT trial. Tissue Microarray slides were digitally scanned and signal quantified by user-defined macros. Statistical analyses (univariate and multivariate) of 5-year disease-free survival (DFS) and 5-year overall survival used binary cut-offs (H score low/high expression). RESULTS: In patients with squamous cell carcinoma (SCC), ATM, p53, PARP1, ERCC1, and MSH2 displayed significant (borderline) predictive values, mainly on DFS with chemotherapy efficacy limited to low marker levels. Adenocarcinoma (ADC) results were not significant. BRCA1 and XPF were not significant for predictive modeling in either SCC or ADCs. CONCLUSION: Here predictive utility of DNA repair enzymes co-segregates with SCC histology, focusing their predictive value to this histological subclass of NSCLC. Distinct mechanisms of chemotherapeutic response or resistance might exist among histological subclasses of solid tumors.

ERCC1 influence on the incidence of brain metastases in patients with non-squamous NSCLC treated with adjuvant cisplatin-based chemotherapy.

BACKGROUND: We recently demonstrated that excision repair cross-complementing group 1 protein (ERCC1) is predictive of adjuvant cisplatin-based chemotherapy benefit in resected non-small-cell lung cancer (NSCLC). Non-squamous cell carcinomas (non-SCCs) carry an increased risk of brain metastases (BMs). We hypothesised that there might be an increased incidence of BMs in ERCC1-negative non-SCCs when treated with adjuvant cisplatin-based chemotherapy. PATIENTS AND METHODS: Incidence of BMs and histoclinical parameters were analysed in a population of 761 patients enrolled in the International Adjuvant Lung Cancer Trial. A subgroup analysis was carried out in patients with ERCC1-negative non-SCCs. RESULTS: Of 761 patients, 98 developed BMs alone or in association with other metastatic sites, with a 5-year incidence rate of 18.0% (14.7%-21.8%). In the multivariate analysis, the clinical parameters associated with the occurrence of BMs were the nodal status (P = 0.02) and histological type [give hazard ratio (HR) for non-squamous to quantify introduction assertion, P = 0.002]. Chemotherapy had no effect on BMs [HR = 1.4 (0.90-2.1), P = 0.14]. In patients with non-SCC histology (n = 335), adjuvant chemotherapy was associated with an increased risk of BMs [HR = 2.1 (1.01-4.3), P = 0.04] for ERCC1-negative tumours, whereas there was no evidence of an effect on BMs for ERCC1-positive tumours [HR = 1.1 (0.38-3.0), P = 0.90]. Nevertheless, these two effects are not different (P = 0.30 for interaction) possibly due to a lack of power in this subgroup. CONCLUSIONS: This study suggests that adjuvant cisplatin-based chemotherapy is associated with an increased risk of BMs in patients with resected chemosensitive non-SCCs. If confirmed, these data could provide a rationale for new follow-up and/or prophylactic strategies.

Effects of CERA (continuous erythropoietin receptor activator) in patients with advanced non-small-cell lung cancer (NSCLC) receiving chemotherapy: results of a phase II study.

BACKGROUND: Continuous erythropoietin receptor activator (CERA; methoxy polyethylene glycol-epoetin beta) is a new erythropoiesis-stimulating agent with a prolonged half-life. The objective of this study was to select a starting dose of CERA for the treatment of anemia in non-small-cell lung cancer (NSCLC) patients. PATIENTS AND METHODS: The study was an open-label randomized phase II trial containing four treatment groups of patients with anemia and stage IIIB or IV NSCLC. The fourth treatment group was a reference group of patients treated with darbepoetin alfa administered at either 6.75 µg/kg s.c. every 3 weeks or 2.25 µg/kg weekly. Due to observed imbalances in death across treatment arms, this study was prematurely terminated. RESULTS: The primary efficacy parameter of the mean hemoglobin (Hb) change from baseline during weeks 5-13 was +0.03 g/dl, +0.50 g/dl, and -0.02 g/dl in the CERA 6.3, 9, and 12 µg/kg dose groups, respectively, and +0.26 g/dl in the darbepoetin alfa dose group (P value not significant for all three study arms). Eight (21%), 12 (32%), 9 (24%), and 4 (10%) patients in the CERA 6.3, 9, and 12 µg/kg and darbepoetin groups, respectively, died. CONCLUSION: In this phase II study in patients with stage IIIB or IV NSCLC receiving chemotherapy, none of the four treatment arms showed an adequate increase in mean Hb level.

Conquering lung cancer: current status and prospects for the future.

Lung cancer is a major global health problem. Several strategies are required to conquer this cancer. Stricter implementations of tobacco control measures are necessary. Early detection programs should be implemented to decrease lung cancer mortality. Although chemotherapy remains a cornerstone of treatment, targeted therapies and immune checkpoint inhibitors improved treatment of metastatic cancers and are hoped to improve outcome of adjuvant and induction therapies. Novel immunotherapy approaches hold great promise. Better understanding of the molecular biology of lung cancer should lead to rational drug design.

Randomized phase II study of cetuximab plus cisplatin/vinorelbine compared with cisplatin/vinorelbine alone as first-line therapy in EGFR-expressing advanced non-small-cell lung cancer.

BACKGROUND: The Lung Cancer Cetuximab Study is an open-label, randomized phase II pilot study of cisplatin and vinorelbine combined with the epidermal growth factor receptor (EGFR)-targeted monoclonal antibody cetuximab versus cisplatin and vinorelbine alone, in patients with advanced EGFR-expressing, non-small-cell lung cancer (NSCLC). End points of the study are activity, safety and pharmacokinetics. PATIENTS AND METHODS: Following randomization, for a maximum of eight cycles, patients received three-weekly cycles of cisplatin (80 mg/m(2), day 1) and vinorelbine (25 mg/m(2) on days 1 and 8) alone or following cetuximab treatment (initial dose 400 mg/m(2), followed by 250 mg/m(2) weekly thereafter). RESULTS: Eighty-six patients were randomly allocated to the study (43 per arm). Confirmed response rates were 28% in the cisplatin/vinorelbine arm (A) and 35% in the cetuximab plus cisplatin/vinorelbine arm (B). Median progression-free survival (PFS) was 4.6 months in arm A and 5.0 months in arm B, with PFS rates at 12 months of 0% and 15%, respectively. Median survival was 7.3 months in arm A and 8.3 months in arm B. The 24-month survival rates were 0% and 16%, respectively. The cetuximab combination was well tolerated. CONCLUSION: In the first-line treatment of advanced NSCLC, the combination of cetuximab plus cisplatin/vinorelbine demonstrated an acceptable safety profile and the potential to improve activity over cisplatin/vinorelbine alone.

Characterization of immunotoxins active against ovarian cancer cell lines.

The purpose of the present study was to develop immunotoxins directed against human ovarian carcinoma cells. Four monoclonal antibodies (260F9, 454C11, 280D11, and 245E7) were chosen because they were found to bind to various ovarian carcinoma cell lines. These antibodies were covalently linked to either Pseudomonas exotoxin (PE) or ricin A chain (RTA), and the conjugates were tested against five ovarian cancer cell lines (OVCAR-2, -3, -4, -5; A1847). The ability of the immunotoxins to inhibit both protein synthesis and colony formation was evaluated. Qualitatively similar results were obtained for both types of assays. Usually, PE conjugates were more toxic than their corresponding RTA conjugates. 454C11-PE was very toxic for all ovarian carcinoma lines, whereas 454C11-RTA had low activity. Both 260F9-PE and 260F9-RTA were active in all OVCAR cell lines but not in A1847 cells. 280D11-PE was toxic for OVCAR-4; otherwise, 280D11-PE and RTA conjugates of both 280D11 and 245E7 had little activity. Specificity of immunotoxin action was shown by competition by excess antibody, nontoxicity in nontarget cells, and inactivity of an irrelevant immunotoxin. To investigate the basis of antibody-dependent differences in activity of the various immunotoxins, antibody uptake was studied in OVCAR-2 cells, and the results indicate that antibody internalization is one important factor in the activity of immunotoxins.

Expression of a multidrug resistance gene in human cancers.

Many cancers have been cured by chemotherapeutic agents. However, other cancers are intrinsically drug resistant, and some acquire resistance following chemotherapy. Cloning of the cDNA for the human MDR1 gene (also known as PGY1), which encodes the multidrug efflux protein P-glycoprotein, has made it possible to measure levels of MDR1 RNA in human cancers. We report the levels of MDR1 RNA in greater than 400 human cancers. MDR1 RNA levels were usually elevated in untreated, intrinsically drug-resistant tumors, including those derived from the colon, kidney, adrenal gland, liver, and pancreas, as well as in carcinoid tumors, chronic myelogenous leukemia in blast crisis, and cell lines of non-small cell carcinoma of the lung (NSCLC) with neuroendocrine properties. MDR1 RNA levels were occasionally elevated in other untreated cancers, including neuroblastoma, acute lymphocytic leukemia (ALL) in adults, acute nonlymphocytic leukemia (ANLL) in adults, and indolent non-Hodgkin's lymphoma. MDR1 RNA levels were also increased in some cancers at relapse after chemotherapy, including ALL, ANLL, breast cancer, neuroblastoma, pheochromocytoma, and nodular, poorly differentiated lymphoma. Many types of drug-sensitive and drug-resistant tumors, including NSCLC and melanoma, contained undetectable or low levels of MDR1 RNA. The consistent association of MDR1 expression with several intrinsically resistant cancers and the increased expression of the MDR1 gene in certain cancers with acquired drug resistance indicate that the MDR1 gene contributes to multidrug resistance in many human cancers. Thus, evaluation of MDR1 gene expression may prove to be a valuable tool in the identification of individuals whose cancers are resistant to specific agents. The information may be useful in designing or altering chemotherapeutic protocols in these patients.

MDR1 gene expression and treatment outcome in acute myeloid leukemia.

To prospectively assess the role of MDR1 gene expression in patients with de novo acute myeloid leukemia (AML), levels of MDR1 RNA in blast cells were determined at diagnosis and correlated with treatment outcome in 63 patients. MDR1 RNA levels were negative in 29% and positive in 71% of the patients. The complete remission rate in response to induction chemotherapy was 89% for MDR1 RNA-negative patients and 53% for MDR1 RNA-positive patients (P = .008). Expression of the MDR1 gene was observed in most patients who died early or had resistant disease. Kaplan-Meier curves revealed a decrease in both disease-free survival and overall survival of patients with detectable MDR1 gene expression compared with the disease-free survival and overall survival of MDR1 RNA-negative patients (P = .029 and P = .009, respectively). These data indicate that MDR1 gene expression is an unfavorable prognostic factor and suggest that multidrug resistance is important in AML.

Enhancement of the activity of immunotoxins made with either ricin A chain or Pseudomonas exotoxin in human ovarian and epidermoid carcinoma cell lines.

The present study evaluates whether the in vitro activity of immunotoxins can be enhanced by verapamil or by various antagonists of calmodulin (dansylcadaverine, trifluoperazine, chlorpromazine). The following immunotoxins made with either Pseudomonas exotoxin (PE), recombinant ricin A chain (rRTA), or ricin A chain (RTA) were used: HB21-PE and 454A12-rRTA that both recognize the human transferrin receptor; and 260F9-rRTA and 454C11-RTA that both react with human ovarian and breast cancer cells. The cytotoxicity of these immunotoxins was determined in human ovarian carcinoma cell lines and KB cells. Verapamil, that was demonstrated previously to enhance the cell-killing activity of PE immunotoxins, enhanced the activity of several ricin A chain immunotoxins, including 454A12-rRTA, 260F9-rRTA, and 454C11-RTA. Comparing 50% inhibitory dose values for inhibition of protein synthesis by 454A12-rRTA, enhancement ranged from 2- to greater than 25-fold, was dependent on the concentration of verapamil, and was greatest at short incubation times. In addition, the cytotoxicity of HB21-PE and of selected RTA immunotoxins was increased up to 30-fold by the addition of various calmodulin antagonists. The enhancing drugs did not decrease the specificity of the immunotoxins.

Enhancement of the activity of immunotoxins by analogues of verapamil.

Verapamil has been shown to enhance immunotoxin activity but only at concentrations that are too high for in vivo use. Therefore, four structural analogues of verapamil (D792, D595, D528, and Sz45) were evaluated for their ability to enhance the in vitro activity of immunotoxins made with either ricin A chain or Pseudomonas exotoxin. The following immunotoxins were used: HB21-PE and 454A12-rRTA which recognize the human transferrin receptor; and 260F9-rRTA which reacts with human ovarian carcinoma and breast carcinoma cells. The activities of the immunotoxins were determined in ovarian carcinoma cells and in KB cells using inhibition of either protein synthesis or colony formation as a measure for the cytotoxicity of the immunotoxins. Each of the four analogues enhanced the activity of ricin A-immunotoxins in a dose-dependent manner. D792 and D595 also increased the activity of IIB21-PE. Low concentrations of either Sz45 or D528 enhanced the activity of HB21-PE, but high concentrations of these two analogues either had less enhancing potency than low concentrations or even decreased the activity of HB21-PE. Specificity of enhancement by the analogues was shown by competition of the activity of the immunotoxins by the corresponding antibody and by inactivity of an irrelevant immunotoxin. The amount of enhancement ranged from 2-fold to greater than 60-fold and was dependent on the cell line and on the experimental conditions. The enhancing ability of the drugs did not correlate with their calcium-antagonistic activity. When compared with verapamil, D792 and D595 had greater enhancing potency with regard to both ricin A-immunotoxins and Pseudomonas exotoxin-immunotoxins. Greater enhancing potency and less in vivo toxicity makes D792 a candidate for use in the enhancement of immunotoxins in vivo.

Anti-transferrin receptor antibody linked to Pseudomonas exotoxin as a model immunotoxin in human ovarian carcinoma cell lines.

The present in vitro study was performed to evaluate the potential usefulness of immunotoxins in treating human ovarian carcinomas. A monoclonal antibody against the human transferrin receptor was covalently linked to Pseudomonas exotoxin. The activity of this immunotoxin (anti-TFR-PE) was studied in five ovarian carcinoma cell lines, a breast carcinoma cell line (MCF-7), and in KB cells. The ovarian carcinoma cell lines included one previously established cell line (A1847) and four recent isolates obtained from the malignant ascites of patients with metastatic ovarian carcinoma (OVCAR cell lines). While all cell lines showed inhibition of protein synthesis by anti-TFR-PE, there were quantitative differences when the level of protein synthesis was assayed after a 12-hr incubation with the immunotoxin. These differences resulted from different kinetics of anti-TFR-PE activity in the various cell lines. Higher levels of cellular binding and internalization of anti-TFR were shown to contribute to increased toxicity of anti-TFR-PE. Verapamil increased the rate of protein synthesis inhibition and thus enhanced the toxicity of anti-TFR-PE in the OVCAR cell lines.

Potentiation of cytotoxic activity of immunotoxins on cultured human cells.

The cytotoxic activity against human tumor cells of toxic conjugates of Pseudomonas exotoxin with anti-transferrin receptor antibody or epidermal growth factor was potentiated up to 10 to 20-fold by the calcium antagonists verapamil, D-600, and diltiazem and by the lysosomotropic agent beta-glycylphenyl-naphthylamide. The potentiating activity of these agents could be predicted by measuring the inhibition of protein synthesis by the immunotoxins on various cell lines. The use of potentiating agents such as these in combination with immunotoxins may prove useful in the treatment of some human cancers.

Immunocytochemical detection of the multidrug resistance-associated protein and P-glycoprotein in acute myeloid leukemia: impact of antibodies, sample source and disease status.

Immunocytochemical detection of the expression of the MRP gene and the MDR1 gene in clinical specimens might be affected by several factors. Thus, we studied the impact of monoclonal antibodies, sample source (peripheral blood vs bone marrow) and disease status on the expression of multidrug resistance-associated protein (MRP) as well as P-glycoprotein (P-gp) in leukemic cells of patients with acute myeloid leukemia (AML). MRP expression was determined by means of anti-MRP antibodies (QCRL-1, QCRL-3, QCRL-1/QCRL-3 or MRPr1). In the case of P-gp, monoclonal antibodies C219 and MRK16 were used. High MRP expression ranged from 5 to 35% and high P-gp expression from 5 to 14% of the specimens. A fair correlation between results obtained with QCRL-1/QCRL-3 and those obtained with MRPr1, as well as a moderate correlation between C219 and MRK16, were seen. MRP and P-gp expression of peripheral blood blasts were similar to those of bone marrow blasts in the majority of cases. The degrees of MRP expression at the time of diagnosis were also similar to the degrees of expression at relapse, albeit an analysis of sequential MRP expression in 13 patients indicated an increase of expression at relapse in six patients as compared to the time of diagnosis.

Clinical relevance of drug resistance genes in malignant disease.

Drug resistance is a major reason for the failure of anticancer chemotherapy. Multidrug resistance has been recognized as an important type of resistance and can be due to various mechanisms. Here we review the published data on the presence and clinical significance of these mechanisms in solid tumors and hematological malignancies. We also refer to new treatment strategies resulting from the knowledge of the various mechanisms of drug resistance present in malignant diseases.