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. EMSA showed that GM-CSF inhibited IFN-alpha-induced and IFN-gamma-induced IFN-gamma activator sequence (GAS) binding activity. As a consequence, IFN-induced transcription of the early response gene, IFN-stimulated…

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. FLT3-Y842C-transfected 32D cells showed constitutive FLT3 tyrosine phosphorylation and interleukin 3 (IL-3)-independent growth. Treatment with PKC412 led to inhibition of proliferat…

Adjuvant MUC vaccination with tecemotide after resection of colorectal liver metastases: a randomized, double-blind, placebo-controlled, multicenter AIO phase II trial (LICC)

ABSTRACT Resection of colorectal liver metastases (CRLM) is a potential curative treatment for patients with metastatic colorectal cancer (mCRC) with liver-limited disease (LLD). Although long-term survival improved considerably within the last decades, high recurrence rates of 50-75% after resection remain a major challenge.Tecemotide (L-BLP25) is an antigen-specific cancer vaccine inducing immunity against mucin-1 (MUC1). The LICC trial aimed to improve survival in patients with mCRC after R0/R1 resection of CRLM. LICC was a binational, randomized, double-blind, placebo-controlled, multicenter phase 2 study including patients with R0/R1 resected CRLM without evidence of metastatic disease…

Panitumumab in combination with gemcitabine/cisplatin (GemCis) for patients with advanced kRAS WT biliary tract cancer: A randomized phase II trial of the Arbeitsgemeinschaft Internistische Onkologie (AIO).

4082 Background: Biliary tract cancer encompasses a group of genetically heterogeneous tumors. Panitumumab is a human EGFR inhibitor and has shown anti-tumor activity in RAS WT colorectal cancer. M...

A randomized, double-blinded, placebo-controlled multicenter phase II trial of adjuvant immunotherapy with tecemotide (L-BLP25) after R0/R1 hepatic colorectal cancer metastasectomy (LICC): Final results.

480 Background: Hepatic metastasectomy is the only potential curative treatment option for stage IV colorectal cancer (CRC) limited to liver metastases (LM). After R0 resection of LM the high recurrence rate remains a major challenge. L-BLP25 is an antigen-specific cancer vaccine targeting mucin 1 (MUC1). The LICC trial aimed to improve survival outcome in mCRC patients (pts) after R0/R1 LM resection. Methods: This LICC trial, a binational, multicenter, double-blinded, placebo controlled phase II trial, included pts with stage IV LM limited CRC after resection of primary tumor and LM (R0/R1) within the last 8 weeks, ECOG 0/1 and adequate organ function. Pts were 2:1 randomized to receive L…

Clinical Course and Significance of the Novel FLT3-Y842C Mutation in a Patient with AML Treated with PKC412 Monotherapy.

Abstract We recently identified a novel mutation (Y842C) within the tyrosine kinase domain of FLT3 in a patient treated with PKC410 monotherapy (ASH 2003, # 4681). Here, we present follow up studies including the clinical course of the patient and frequency analysis in 110 patients with AML. In addition, we characterized the novel mutation using overexpression of FLT3-Y842C in 32D cells. AML M2 was diagnosed in a 63 year old, male patient in 1993. After having experienced his second relapse upon standard therapy the patient was refractory to alemtuzumab treatment. Due to reduced performance status the patient was not eligible to standard chemotherapy and was enrolled into a phase II trial i…

Survival after secondary liver resection in metastatic colorectal cancer: Comparing data of three prospective randomized European trials ( LICC , CELIM , FIRE ‐3)

Metastatic colorectal cancer (mCRC) patients with liver-limited disease (LLD) have a chance of long-term survival and potential cure after hepatic metastasectomy. However, the appropriate postoperative treatment strategy is still controversial. The CELIM and FIRE-3 studies demonstrated that secondary hepatic resection significantly improved overall survival. The objective of this analysis was to compare these favorable outcome data with recent results from the LICC trial investigating the antigen-specific cancer vaccine tecemotide (L-BLP-25) as adjuvant therapy in mCRC patients with LLD after R0/R1 resection. Data from mCRC patients with LLD and secondary hepatic resection from each study w…

The JAK2 Kinase Inhibitor LS104 Induces Growth-Arrest and Apoptosis in JAK2V617F Positive Cells.

Abstract The JAK2V617F-mutation (V617F) is a novel, highly prevalent molecular marker in Ph-negative myeloproliferative disease (MPD). In vitro, the V617F mutation confers cytokine independent growth of Ba/F3 cells expressing erythropoietin receptor (EpoR) and constitutive activation of the JAK2 kinase and of the JAK-STAT pathway. In a murine bone-marrow transplant model the V617F-mutation alone is sufficient to induce a polycythemia vera-like phenotype. Therefore, mutant JAK2 kinase is a promising target for kinase inhibitor development. In this report, we characterize the small molecule LS104 (previously CR4; Grunberger et al., Blood 2003) as a novel non-ATP-competitive JAK2V617F kinase i…

In BCR-ABL-positive cells, STAT-5 tyrosine-phosphorylation integrates signals induced by imatinib mesylate and Ara-C.

In BCR-ABL-positive cells, the transcription factor STAT-5 is constitutively activated by tyrosine phosphorylation. STAT-5 activation results in upregulation of bcl-X(L) and increased resistance to induction of apoptosis. Here, we investigated the effects of imatinib mesylate and cytosine arabinoside (Ara-C) on STAT-5 tyrosine-phosphorylation, cellular proliferation and induction of apoptosis in cell lines and primary hematopoietic cells. Imatinib mesylate treatment strongly suppressed STAT-5 tyrosine-phosphorylation in K562 and primary CML blasts. In contrast to JAK-2 and PI-3-kinase inhibition, exposure of K562 cells to imatinib mesylate resulted in obvious suppression of proliferation. R…

PICCA study: panitumumab in combination with cisplatin/gemcitabine chemotherapy in KRAS wild-type patients with biliary cancer—a randomised biomarker-driven clinical phase II AIO study

Abstract Background Combination chemotherapy has shown benefit in the treatment of biliary cancer and further improvements might be achieved by the addition of a biological agent. We report here the effect of chemotherapy with the monoclonal EGFR antibody panitumumab as therapy for KRAS wild-type biliary cancer. Patients and methods Patients with advanced biliary tract cancer were randomised (2:1) to receive cisplatin 25 mg/m2 and gemcitabine 1000 mg/m2 on day 1 and day 8/q3w with (arm A) or without panitumumab (arm B; 9 mg/kg BW, i.v q3w). The primary end-point was the evaluation of progression-free survival (PFS) at 6 months. Secondary end-points included objective response rate (ORR), ov…

Protein�A immunoadsorption therapy for refractory, mitomycin�C?associated thrombotic microangiopathy

BACKGROUND: Mitomycin C–associated thrombotic microangiopathy (TMA) has a poor prognosis with limited therapeutic options. Most patients die within 4 months of diagnosis due to pulmonary or renal failure. Here, a patient resistant to total plasma exchange (TPE) and immunosuppressive therapy with glucocorticoids, rituximab, vincristine, and splenectomy who was successfully treated with protein A immunoadsorption is described. CASE REPORT: A 29-year-old woman developed a TMA after chemotherapy with mitomycin C. She presented with thrombocytopenia, pulmonary edema, hemolytic anemia with presence of schistocytes, and renal failure. Immediate TPE (>120 times) and immunosuppressive therapy with g…

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

Abstract 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. LS104 inhibited JAK2 kinase activity in vitro. This effect was not reversible using elevated ATP concentrations, whereas variation of the kinase substrate peptide led to modulation of …

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. The etiology of clinical resistance to FLT3-TKI in AML is unclear but is of major significance for the development of future therapeutic strategies. We searched for mechanisms of resistance in 6 patients with AML who had relapses upon PKC412 treatment. In an …

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. In pharmacokinetic studies, a rapid and dose dependent cellular uptake of LS104 lasting up to 11h could be demonstrated. Combination of LS104 with chemotherapeutic agents markedly enhanced cytotoxic effects. Recently, a…

A randomized, double-blind, placebo-controlled, multicenter, multinational, phase II trial immunotherapy with L-BLP25 (tecemotide) in patients with colorectal carcinoma following R0/R1 hepatic metastasectomy.

TPS3124^ Background: 15-20% of all patients (pts) diagnosed with colorectal cancer (crc) develop metastases (mets) surgical resection remains the only potentially curative treatment available. Current 5-year survival rate following R0 resection of liver mets lies between 28-39%, recurrence occurs in up to 70% of pts. To date, adjuvant chemotherapy has not significantly improved clinical outcomes. The primary objective of the ongoing LICC trial (L-BLP25 In Colorectal Cancer) is to determine whether L-BLP25, an active MUC1-specific cancer immunotherapy, extends recurrence-free survival (RFS) time over placebo in crc pts following R0/R1 resection of liver mets known to highly express MUC1 gly…

A randomized, double-blind, placebo-controlled, multicenter, multinational, phase II trial of L-BLP25 in patients with colorectal carcinoma following R0/R1 hepatic metastasectomy.

TPS3641^ Background: Approximately 15-20% of patients diagnosed with colorectal cancer (crc) develop metastatic disease. Surgical resection remains the only potentially curative treatment. 5-year survival following R0-resection of liver metastases lies ~28 -39%. Recurrence occurs in ~70% of pts. Adjuvant chemotherapy has not significantly improved clinical outcomes. The primary objective of the LICC trial (L-BLP25 in Colorectal Cancer) is to analyze whether L-BLP25, an active cancer immunotherapy, extends recurrence-free survival (RFS) time over placebo in colorectal cancer pts following R0/R1 resection of hepatic metastases. L-BLP25 targets MUC1 glycoprotein, which is highly expressed in …

Docetaxel, oxaliplatin, and fluorouracil/leucovorin (FLOT) for resectable esophagogastric cancer: Updated results from multicenter, randomized phase 3 FLOT4-AIO trial (German Gastric Group at AIO)

LS104, a Novel Kinase Inhibitor, Induces Apoptosis, Synergizes with Cytostatic Drugs and Is Targeting the Receptor Tyrosine Kinase FLT3.

Abstract Fms-like tyrosine kinase 3 (FLT3), a member of the class III tyrosine kinase receptor family, is expressed in up to 90% of acute myeloid leukemia (AML). Activating mutations like internal tandem duplication (ITD) of the juxtamembrane domain and kinase domain point mutations are found in approximately 35% of AML-cases and are considered to represent an attractive therapeutic target. In this study, we report that the novel hydroxystyryl-acrylonitrile compound LS104 induces potent cytotoxic effects in FLT3 ITD-positive leukemic cells. As a cellular model to investigate FLT3-ITD specific effects we used 32D myeloid cells stably transfected with FLT3-ITD and wt-FLT3, respectively. In MT…

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

Abstract 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 β-2 sheet of the first kinase domain (FLT3_ITD627E) induces dramatic up-regulation of the anti-apoptotic myeloid cell leukemia 1 protein (MCL-1). Using RNA…

Survival after secondary liver resection in metastatic colorectal cancer: A comparative analysis of the LICC trial with historical controls (CELIM, FIRE-3).

e15025 Background: Metastatic colorectal cancer (mCRC) patients (pts) with liver-limited disease (LLD) have a chance of long-term overall survival (OS) and potential cure after complete hepatic metastasectomy. The appropriate postoperative treatment strategy is still controversial. L-BLP25 as antigen-specific cancer vaccine targeting mucin 1 (MUC1) was recently evaluated as adjuvant therapy in mCRC pts after R0/R1 LLD resection (LICC trial, NCT01462513). Here we compared the LICC surveillance program and efficacy results for secondarily resected LLD pts versus historical controls, i.e. the CELIM trial (Folprecht et al, Ann Oncol 2014) of potentially resectable LLD mCRC pts and a FIRE-3-LLD…

Survival after primary liver resection in metastatic colorectal cancer: A comparative analysis of the LICC trial with historical controls (FFCD ACHBTH AURC 9002 trial and EORTC Intergroup trial 40983).

e15019 Background: Metastatic colorectal cancer (mCRC) patients (pts) with liver-limited disease (LLD) have a chance of long-term survival and cure after hepatic metastasectomy. The optimal treatment after primary liver resection remains controversial. Here we compare results from the LICC trial with historical controls, the FFCD ACHBTH AURC 9002 trial (FFCD; Portier et al., 2006) and the EORTC Intergroup trial 40983 (EORTC; Nordlinger et al., 2008, 2013). The three trials investigated pts with mCRC LLD who underwent primary hepatic resection. Methods: LICC, FFCD and EORTC were compared regarding pts characteristics, treatment, surveillance and efficacy outcomes. LICC pts received the adju…

Perioperative chemotherapy with fluorouracil plus leucovorin, oxaliplatin, and docetaxel versus fluorouracil or capecitabine plus cisplatin and epirubicin for locally advanced, resectable gastric or gastro-oesophageal junction adenocarcinoma (FLOT4): a randomised, phase 2/3 trial

Background Docetaxel-based chemotherapy is effective in metastatic gastric and gastro-oesophageal junction adenocarcinoma. This study reports on the safety and efficacy of the docetaxel-based triplet FLOT (fluorouracil plus leucovorin, oxaliplatin and docetaxel) as a perioperative therapy for patients with locally advanced, resectable tumours. Methods In this controlled, open-label, phase 2/3 trial, we randomly assigned 716 patients with histologically-confirmed advanced clinical stage cT2 or higher or nodal positive stage (cN+), or both, resectable tumours, with no evidence of distant metastases, via central interactive web-based-response system, to receive either three pre-operative and t…