A randomized, multicenter phase II study comparing efficacy, safety and tolerability of two dosing regimens of cisplatin and pemetrexed in patients with advanced or metastatic non-small-cell lung cancer.

Background: Pemetrexed and cisplatin is a first-line standard in non-squamous non-small-cell lung cancer without targetable mutations. It became the backbone of checkpoint-inhibitor-chemotherapy combinations. Single high doses of cisplatin pose toxicity risks and require hyperhydration, potentially prolonging outpatient application.

Rapid and Highly Sensitive Detection of Therapeutically Relevant Oncogenic Driver Mutations in EBUS-TBNA Specimens From Patients With Lung Adenocarcinoma.

Background: First-line afatinib treatment prolongs overall survival in patients with metastatic non-small-cell lung cancer (NSCLC) harboring exon 19 deletion of epidermal growth factor receptor (EGFRdelEx19) mutations. In contrast, Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) mutations are negative predictors for benefit from EGFR-targeting agents. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is well-established for lung cancer diagnosis and staging.

Comprehensive Biomarker Analyses in Patients with Advanced or Metastatic Non-Small Cell Lung Cancer Prospectively Treated with the Polo-Like Kinase 1 Inhibitor BI2536.

Background: Polo like kinase 1 (PLK1) is frequently upregulated in tumors and is thus viewed as a promising therapeutic target in various cancers. Several PLK1 inhibitors have recently been developed and clinically tested in solid cancers, albeit with limited success. So far, no predictive biomarkers for PLK1 inhibitors have been established.

Molecular dissection of effector mechanisms of RAS-mediated resistance to anti-EGFR antibody therapy.

Monoclonal antibodies targeting the epidermal growth factor receptor (EGFR), cetuximab and panitumumab, are a mainstay of metastatic colorectal cancer (mCRC) treatment. However, a significant number of patients suffer from primary or acquired resistance. RAS mutations are negative predictors of clinical efficacy of anti-EGFR antibodies in patients with mCRC.

Deregulated BCL-2 family proteins impact on repair of DNA double-strand breaks and are targets to overcome radioresistance in lung cancer.

Purpose: DNA damage-induced cell death is a major effector mechanism of radiotherapy. Aberrant expression of anti-apoptotic BCL-2 family proteins is frequently observed in lung cancers. Against this background, we studied radioresistance mediated by BCL-2 family proteins at the mechanistic level and its potential as target for radiochemotherapy.

Inactivation of Capicua drives cancer metastasis.

Metastasis is the leading cause of death in people with lung cancer, yet the molecular effectors underlying tumor dissemination remain poorly defined. Through the development of an in vivo spontaneous lung cancer metastasis model, we show that the developmentally regulated transcriptional repressor Capicua (CIC) suppresses invasion and metastasis. Inactivation of CIC relieves repression of its effector ETV4, driving ETV4-mediated upregulation of MMP24, which is necessary and sufficient for metastasis.

Circulating U2 small nuclear RNA fragments as a diagnostic and prognostic biomarker in lung cancer patients.

Purpose: Lung cancer accounts for one in five cancer deaths. Broad screening strategies for high-risk populations are unavailable, and the validation of biomarkers for early cancer detection remains a prime interest. Therefore, we investigated the value of circulating U2 small nuclear RNA fragments (RNU2-1f) as a biomarker for diagnosis, prognosis estimation and treatment monitoring in a large lung cancer cohort.

MITF is a critical regulator of the carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) in malignant melanoma.

The multifunctional Ig-like carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is neo-expressed in the majority of malignant melanoma lesions. CEACAM1 acts as a driver of tumor cell invasion, and its expression correlates with poor patient prognosis. Despite its importance in melanoma progression, how CEACAM1 expression is regulated is largely unknown.

Development of a highly sensitive and specific method for detection of circulating tumor cells harboring somatic mutations in non-small-cell lung cancer patients.

Background: Oncogenic mutations are powerful predictive biomarkers for molecularly targeted cancer therapies. For mutation detection patients have to undergo invasive tumor biopsies. Alternatively, archival samples are used which may no longer reflect the actual tumor status.

Stabilization of physical RAF/14-3-3 interaction by cotylenin A as treatment strategy for RAS mutant cancers.

One-third of all human cancers harbor somatic RAS mutations. This leads to aberrant activation of downstream signaling pathways involving the RAF kinases. Current ATP-competitive RAF inhibitors are active in cancers with somatic RAF mutations, such as BRAF(V600) mutant melanomas.

DOG1 regulates growth and IGFBP5 in gastrointestinal stromal tumors.

Gastrointestinal stromal tumors (GIST) are characterized by activating mutations of KIT or platelet-derived growth factor receptor α(PDGFRA), which can be therapeutically targeted by tyrosine kinase inhibitors (TKI) such as imatinib. Despite long-lasting responses, most patients eventually progress after TKI therapy. The calcium-dependent chloride channel DOG1 (ANO1/TMEM16A), which is strongly and specifically expressed in GIST, is used as a diagnostic marker to differentiate GIST from other sarcomas.

Individual dose and scheduling determine the efficacy of combining cytotoxic anticancer agents with a kinase inhibitor in non-small-cell lung cancer.

Purpose: To investigate the combination of conventional cytotoxic anticancer agents and a small molecule kinase inhibitor in preclinical models of non-small-cell lung cancer (NSCLC).

Methods: We compared the induction of apoptosis by DNA-damaging anticancer drugs and PKC412, a predominantly protein kinase C (PKC)-specific small molecule inhibitor, in six NSCLC cell lines of different histologic and genetic backgrounds. The outcome of various combinations and schedules of DNA-damaging agents and PKC412 was studied, and isobolograms were calculated.

Pharmacologic inhibition of mTOR antagonizes the cytotoxic activity of pemetrexed in non-small cell lung cancer.

Purpose: Pemetrexed, an inhibitor of thymidylate synthase (TS) and additional folate-dependent enzymes, is clinically active in patients suffering from "non-squamous" non-small cell lung cancer (NSCLC). High expression of TS has been implied as biomarker predictive of resistance to pemetrexed. Against this background, we studied whether inhibition of mTOR could lower expression of TS and thus sensitize NSCLC cells to pemetrexed.

Functional and clinical characterization of the putative tumor suppressor WWOX in non-small cell lung cancer.

Introduction: The oxidoreductase WWOX was initially described as a putative tumor suppressor in breast cancer. Non-small cell lung cancers (NSCLCs) frequently show aberrant WWOX expression. Herein, we characterized WWOX at a functional level in preclinical NSCLC models and in primary NSCLC biopsies.

Insertion of FLT3 internal tandem duplication in the tyrosine kinase domain-1 is associated with resistance to chemotherapy and inferior outcome.

To evaluate internal tandem duplication (ITD) insertion sites and length as well as their clinical impact in younger adult patients with FLT3-ITD-positive acute myeloid leukemia (AML), sequencing after DNA-based amplification was performed in diagnostic samples from 241 FLT3-ITD-mutated patients. All patients were treated on 3 German-Austrian AML Study Group protocols. Thirty-four of the 241 patients had more than 1 ITD, leading to a total of 282 ITDs; the median ITD length was 48 nucleotides (range, 15-180 nucleotides).

A novel molecular mechanism of primary resistance to FLT3-kinase inhibitors in AML.

Currently, FLT3 tyrosine kinase inhibitors (TKIs) are emerging as the most promising drug therapy to overcome the dismal prognosis of acute myelogenous leukemia (AML) patients harboring internal tandem duplications (ITDs) of FLT3. However, up-front drug resistance occurs in approximately 30% of patients, and molecular mechanisms of resistance are poorly understood. Here, we have uncovered a novel mechanism of primary resistance to FLT3 TKIs in AML: an FLT3 receptor harboring a nonjuxtamembrane ITD atypically integrating into the beta-2 sheet of the first kinase domain (FLT3_ITD627E) induces dramatic up-regulation of the anti-apoptotic myeloid cell leukemia 1 protein (MCL-1).

The kinase inhibitor LS104 induces apoptosis, enhances cytotoxic effects of chemotherapeutic drugs and is targeting the receptor tyrosine kinase FLT3 in acute myeloid leukemia.

Activating mutations of FLT3 are found in approximately one-third of acute myeloid leukemia (AML)-cases and are considered to represent an attractive therapeutic target. In this study, we report that the hydroxystyryl-acrylonitrile compound LS104 inhibits proliferation and induces potent cytotoxic effects in FLT3 expressing leukemic cells in vitro. Immunoblot and phosphoprotein-FACS analysis demonstrated inhibiton of phosphorylation of FLT3-ITD and of its downstream targets.

Identification of a novel type of ITD mutations located in nonjuxtamembrane domains of the FLT3 tyrosine kinase receptor.

In acute myeloid leukemia (AML), internal tandem duplications (ITDs) of the juxtamembrane (JM) of FLT3 have been shown to play a crucial role in driving proliferation and survival of the leukemic clone. Here, we report the identification of FLT3_ITD mutations located in non-JM domains of the FLT3-receptor. This novel type of FLT3_ITD mutation was found in 216 of 753 (28.

LS104, a non-ATP-competitive small-molecule inhibitor of JAK2, is potently inducing apoptosis in JAK2V617F-positive cells.

The activating JAK2V617F mutation has been described in the majority of patients with BCR-ABL-negative myeloproliferative disorders (MPD). In this report, we characterize the small-molecule LS104 as a novel non-ATP-competitive JAK2 inhibitor: Treatment of JAK2V617F-positive cells with LS104 resulted in dose-dependent induction of apoptosis and inhibition of JAK2 autophosphorylation and of downstream targets. Activation of these targets by JAK2 was confirmed in experiments using small interfering RNA.

Cross-inhibition of interferon-induced signals by GM-CSF through a block in Stat1 activation.

We investigated the effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) on biologic signals induced by interferon-alpha (IFN-alpha) and IFN-gamma. In hematopoietic cell lines, IFN-induced signaling was investigated by Western blotting, electrophoretic mobility shift assays (EMSA), flow cytometry, protein-tyrosine phosphatase (PTP) assays, and RT-PCR. GM-CSF inhibited IFN-alpha-induced and IFN-gamma-induced Stat1 tyrosine phosphorylation in a time-dependent manner.

Clinical resistance to the kinase inhibitor PKC412 in acute myeloid leukemia by mutation of Asn-676 in the FLT3 tyrosine kinase domain.

Activating mutations in the FLT3 tyrosine kinase (TK) occur in approximately 35% of patients with acute myeloid leukemia (AML). Therefore, targeting mutated FLT3 is an attractive therapeutic strategy, and early clinical trials testing FLT3 TK inhibitors (TKI) showed measurable clinical responses. Most of these responses were transient; however, in a subset of patients blast recurrence was preceded by an interval of prolonged remission.

Identification of a novel activating mutation (Y842C) within the activation loop of FLT3 in patients with acute myeloid leukemia (AML).

Fms-like tyrosine kinase 3 (FLT3) receptor mutations as internal tandem duplication (ITD) or within the kinase domain are detected in up to 35% of patients with acute myeloid leukemia (AML). N-benzoyl staurosporine (PKC412), a highly effective inhibitor of mutated FLT3 receptors, has significant antileukemic efficacy in patients with FLT3-mutated AML. Mutation screening of FLT3 exon 20 in AML patients (n = 110) revealed 2 patients with a novel mutation (Y842C) within the highly conserved activation loop of FLT3.

Efficacy and safety of imatinib in adult patients with c-kit-positive acute myeloid leukemia.

This phase 2 pilot study was conducted to determine the efficacy and safety of imatinib mesylate in patients with c-kit-positive acute myeloid leukemia (AML) refractory to or not eligible for chemotherapy. Twenty-one patients were enrolled and received imatinib 600 mg orally once daily. Five responses were seen primarily in patients, starting with relatively low blast counts in bone marrow (BM) and peripheral blood (PB): 2 patients who were considered refractory on chemotherapy on the basis of persistence of blasts in PB and BM met the criteria for complete hematologic remission, 1 patient had no evidence of leukemia, and 2 patients achieved a minor response.

Sustained complete hematologic remission after administration of the tyrosine kinase inhibitor imatinib mesylate in a patient with refractory, secondary AML.

Imatinib mesylate, a tyrosine kinase inhibitor targeting bcr-abl, platelet-derived growth factor receptor (PDGF-R), and c-Kit, effectively induces hematologic and cytogenetic remissions in bcr-abl(+) chronic myeloid leukemia (CML) and acute lymphoblastic leukemia (ALL) with only mild to moderate side effects. Here, we describe the successful treatment of a 64-year-old man with c-Kit(+) secondary acute myeloid leukemia (AML) refractory to standard chemotherapy. Upon 2 weeks of imatinib mesylate administration, the patient achieved a complete hematologic remission in peripheral blood.