imetelstat and nintedanib

Functional blood vasculature is essential for tumor progression. The main signalization pathways that play a key role in the survival and growth of tumor vessels originate from the VEGF-, PDGF- and FGF tyrosine kinase receptors. In the past decade, significant results have been published on receptor tyrosine kinase inhibitors (RTKIs). In this paper, the mechanisms of action and the results so far available of experimental and clinical studies on multi-target antiangiogenic TKIs are discussed. On the one hand, notable achievements have been made recently and these drugs are already used in clinical practice in some patient populations. On the other hand, the optimal combination and dosage of these drugs, selection of the apropriate biomarker and better understanding of the conflicting role of PDGFR and FGFR signaling in angiogenesis remain future challenges.

Topics: Angiogenesis Inhibitors; Animals; Axitinib; Benzenesulfonates; Humans; Imidazoles; Indazoles; Indoles; Neoplasms; Neovascularization, Pathologic; Niacinamide; Oligonucleotides; Phenylurea Compounds; Phthalazines; Piperidines; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Pyridines; Pyrimidines; Pyrroles; Quinazolines; Receptor Protein-Tyrosine Kinases; Receptors, Fibroblast Growth Factor; Receptors, Platelet-Derived Growth Factor; Receptors, Vascular Endothelial Growth Factor; Signal Transduction; Sorafenib; Sulfonamides; Sunitinib

Angiogenesis is essential for tumor growth and metastasis. The main regulators of the process are the signaling cascades of VEGF-, PDGF- and FGF receptors. Inhibition of these pathways holds potential therapeutic benefit not only for cancer patients, but also for the treatment of other diseases. This paper summarizes the experimental and clinical results of studies available so far on the multi-target tyrosine kinase inhibitor nintedanib (BIBF 1120). According to these studies, nintedanib effectively inhibits VEGFR-, PDGFR- and FGFR signalization and thus the proliferation and survival of cell types which highly express these receptors (i.e. endothelial and smooth muscle cells and pericytes). In vitro studies and in vivo xenograft experiments have provided promising results. In the clinical setting, BIBF 1120 seems to be effective and well tolerated in various tumor types, such as lung, prostate, colorectal and hepatocellular carcinoma, as well as in gynecological tumors. The main adverse events are gastrointestinal toxicities and the reversible elevation of liver enzyme levels. Nintedanib might also be combined with paclitaxel, carboplatin, pemetrexed and docetaxel. There are several ongoing clinical trials testing the efficacy of BIBF 1120.

Topics: Animals; Antineoplastic Agents; Axitinib; Benzenesulfonates; Carcinoma, Hepatocellular; Clinical Trials as Topic; Colorectal Neoplasms; Digestive System; Enzyme Inhibitors; Female; Genital Neoplasms, Female; Humans; Imidazoles; Indazoles; Indoles; Liver Neoplasms; Lung Neoplasms; Male; Neoplasms; Niacinamide; Oligonucleotides; Phenylurea Compounds; Phthalazines; Piperidines; Prostatic Neoplasms; Protein-Tyrosine Kinases; Pyridines; Pyrimidines; Quinazolines; Receptors, Fibroblast Growth Factor; Receptors, Platelet-Derived Growth Factor; Receptors, Vascular Endothelial Growth Factor; Signal Transduction; Sorafenib; Sulfonamides; Xenograft Model Antitumor Assays