Publications by authors named "Dirk J Richel"

Background: Patients with a newly diagnosed glioblastoma multiforme (GBM) have a high risk of recurrent disease with a dismal outcome despite intensive treatment of sequential surgery and chemoradiotherapy with temozolomide (TMZ), followed by TMZ as a single agent. Bevacizumab (BV) may increase response rates to chemotherapy in the recurrent treatment setting of GBM. We hypothesized that a neoadjuvant treatment strategy for patients with newly diagnosed GBM using chemoradiotherapy plus BV would improve resectability and thus survival.

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Protease-activated receptor-2 (PAR-2) is a G protein-coupled receptor that functions as a cell-surface sensor for coagulation factors and other proteases associated with the tumour microenvironment. Pancreatic cancer cells express high levels of PAR-2 and activation of PAR-2 may induce their proliferation and migration. Interestingly, however, PAR-2 expression is increased in stroma-rich pancreatic cancer regions, suggesting a potential role of PAR-2 in the tumour microenvironment.

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Background: Axitinib is a potent, selective inhibitor of vascular endothelial growth factor (VEGF) receptors 1, 2, and 3. A randomised phase 2 trial of gemcitabine with or without axitinib in advanced pancreatic cancer suggested increased overall survival in axitinib-treated patients. On the basis of these results, we aimed to assess the effect of treatment with gemcitabine plus axitinib on overall survival in a phase 3 trial.

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Background: The relevance of angiogenesis inhibition in the treatment of glioblastoma multiforme (GBM) should be considered in the unique context of malignant brain tumours. Although patients benefit greatly from reduced cerebral oedema and intracranial pressure, this important clinical improvement on its own may not be considered as an anti-tumour effect.

Discussion: GBM can be roughly separated into an angiogenic component, and an invasive or migratory component.

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Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor. The identification of 'cancer stem cells' (CSC) has shed new light on the potential mechanism of therapy resistance of these tumors. Because these cells appear to be more resistant to conventional treatments, they are thought to drive tumor regrowth after therapy.

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Background: The treatment of recurrent transitional cell carcinoma (TCC) remains an unmet clinical need. This study assessed lapatinib, a dual tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR) and HER-2, as second-line therapy in patients with locally advanced or metastatic TCC.

Methods: This was a single-arm, multicenter, open-label, prospective phase 2 study.

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Background: Fluoropyrimidine-based chemotherapy plus the anti-vascular endothelial growth factor (VEGF) antibody bevacizumab is standard first-line treatment for metastatic colorectal cancer. We studied the effect of adding the anti-epidermal growth factor receptor (EGFR) antibody cetuximab to a combination of capecitabine, oxaliplatin, and bevacizumab for metastatic colorectal cancer.

Methods: We randomly assigned 755 patients with previously untreated metastatic colorectal cancer to capecitabine, oxaliplatin, and bevacizumab (CB regimen, 378 patients) or the same regimen plus weekly cetuximab (CBC regimen, 377 patients).

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Activity of receptor tyrosine kinases (RTK) in colorectal cancer (CRC) is associated with enhanced tumor growth and a poorer prognosis. In addition, cyclooxygenase-2 (COX-2) expression contributes to tumor growth and invasion. COX-2 inhibitors exhibit important anticarcinogenic potential against CRC, but the molecular mechanism underlying this effect and the relation with RTK signaling remain the subject of intense research effort.

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Purpose: This phase I study was designed to determine the optimally tolerated regimen (OTR), safety, and clinical activity of lapatinib in combination with FOLFOX4 [oxaliplatin/leucovorin/5-fluorouracil (5-FU)] in patients with solid tumors. Furthermore, the pharmacokinetics of lapatinib, oxaliplatin, and 5-FU when given alone and in combination were evaluated.

Experimental Design: This study was conducted in two parts.

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Objectives: To evaluate the effects of neoadjuvant therapy with the selective cyclooxygenase-2 (COX-2) inhibitor celecoxib in vitro and in patients with esophageal adenocarcinoma on COX-2 and MET expression.

Summary Background Data: High COX-2 and/or MET expression levels are negative prognostic factors for adenocarcinoma of the esophagus. Nonsteroidal anti-inflammatory drugs (NSAIDs) and selective COX-2 inhibitors exert anticancer mechanisms as is evident from epidemiologic studies and from experimental models for esophageal cancer.

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Most patients with oesophageal cancer present with locally advanced or metastatic disease. In an effort to improve the results of surgery in patients with operable disease, strategies to incorporate radiotherapy and chemotherapy, preoperatively (neoadjuvant) and postoperatively (adjuvant), have been extensively investigated in numerous clinical trials. Meta-analyses of neoadjuvant trials did not demonstrate a survival advantage for neoadjuvant chemotherapy or concurrent chemoradiotherapy.

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