FLT3-ITD is the most predominant mutation in AML being expressed in about one-third of AML patients and is associated with a poor prognosis. Efforts to better understand FLT3-ITD downstream signaling to possibly improve therapy response are needed. We have previously described FLT3-ITD-dependent phosphorylation of CSF2RB, the common receptor beta chain of IL-3, IL-5, and GM-CSF, and therefore examined its significance for FLT3-ITD-dependent oncogenic signaling and transformation.
View Article and Find Full Text PDFAn important limitation of FLT3 tyrosine kinase inhibitors (TKIs) in FLT3-ITD positive AML is the development of resistance. To better understand resistance to FLT3 inhibition, we examined FLT3-ITD positive cell lines which had acquired resistance to midostaurin or sorafenib. In 6 out of 23 TKI resistant cell lines we were able to detect a JAK1 V658F mutation, a mutation that led to reactivation of the CSF2RB-STAT5 pathway.
View Article and Find Full Text PDFRelapsed or refractory (R/R) disease remains challenging in acute myeloid leukemia (AML), especially in elderly patients not considered eligible for intensive treatment options. We retrospectively evaluated the safety and efficacy of low-dose melphalan (LD-Mel) in a multicenter analysis in patients over 65 years with R/R AML, who previously had received ≥1 non-curative treatment line. The study included 31 patients (median age 77 years) with 1-4 previous treatment lines.
View Article and Find Full Text PDFIndividuals with acute myeloid leukemia (AML) harboring an internal tandem duplication (ITD) in the gene encoding Fms-related tyrosine kinase 3 (FLT3) who relapse after allogeneic hematopoietic cell transplantation (allo-HCT) have a 1-year survival rate below 20%. We observed that sorafenib, a multitargeted tyrosine kinase inhibitor, increased IL-15 production by FLT3-ITD leukemia cells. This synergized with the allogeneic CD8 T cell response, leading to long-term survival in six mouse models of FLT3-ITD AML.
View Article and Find Full Text PDFABL tyrosine kinase inhibitors (TKI) like Imatinib, Dasatinib and Nilotinib are the gold standard in conventional treatment of CML. However, the emergence of resistance remains a major problem. Alternative therapeutic strategies of ABL TKI-resistant CML are urgently needed.
View Article and Find Full Text PDFPurpose: To investigate the presence and distribution of l-kynurenine aminotransferases immunoreactivity in human and animal lenses during cataract formation.
Methods: Immunohistochemistry was conducted using polyclonal antibodies against KAT I, KAT II and KAT III on sections of 26 anterior capsules from patients undergoing surgical treatment of anterior subcapsular cataract (ASC) and 22 cataractous lenses from human eyes enucleated because of choroidal malignant melanoma. Additionally, the eyes of 11-month-old DBA/2J mice (6 eyes) were investigated (with KAT I and II).
Background: Corpora amylacea (CAm) are a hallmark of aging and neurodegeneration. The presence of kynurenine aminotransferases I and II (KAT I and II) in CAm in the human retina and optic nerve has been already shown. The present study aimed to examine kynurenine aminotransferase III (KAT III) immunoreactivity in CAm in the human retina and optic nerve.
View Article and Find Full Text PDFBackground: This retrospective study examines the histopathological changes, especially the occurrence of retrocorneal membranes, in irreversible graft failure after penetrating keratoplasty.
Patients/materials And Methods: 371 corneas of 308 patients were examined. The examination was carried out using a light microscope.
Purpose: Bevacizumab eyedrops inhibit corneal neovascularization. The purpose of this study was to analyze the safety profile of VEGF-A neutralization at the ocular surface.
Methods: Bevacizumab eyedrops (5 mg/mL) and an antimurine VEGF-A antibody (250 microg/mL) were applied to normal murine corneas five times a day for 7 and 14 days.
Purpose: To analyze whether lymphatic vessels can invade the normally alymphatic eye (lymphangiogenesis) in patients with malignant melanoma of the ciliary body with extraocular extension and to correlate these findings with metastasis-free survival.
Methods: Ten enucleated globes with the histopathologically and immunohistochemically (S-100, HMB-45, PNL-2, and Melan-A) confirmed diagnosis of malignant melanoma of the ciliary body with extraocular extension were matched with 10 globes with a ciliary body melanoma without extraocular extension regarding tumor size, cell type, melanin content, mitotic count, vascular networks, and patients' age. In all 20 cases, immunohistochemistry was performed to identify lymphatic vessels by using LYVE-1 and podoplanin as specific markers for lymphatic vascular endothelium.
Br J Ophthalmol
February 2009
Aim: To investigate the effect of timolol and latanoprost on the extracellular matrix organisation, inflammatory infiltration, and expression of matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) in the human conjunctiva.
Methods: Conjunctival biopsies were obtained from the inferior fornix during routine cataract surgery from 20 patients with primary open-angle glaucoma, who had received a monotherapy either with timolol or latanoprost, and from 10 non-glaucomatous patients. Specimens were investigated by light microscopy, immunohistochemistry using antibodies against MMP-1,-3, TIMP-2,-3 and CD 68 antibodies and by quantitative transmission electron microscopy.
Introduction: Corpora amylacea (CAm) occur in the optic nerve and in retinal ageing and degeneration. Cellular expression of L-kynurenine aminotransferases (KAT I and II) in the avian and rodent retina and its changes in retinal development and neurodegeneration have been documented. This study examines KAT I and II immunoreactivity in CAm in the human retina and optic nerve.
View Article and Find Full Text PDFPurpose: To evaluate the efficacy of the laser photolysis system (LPS) (A.R.C.
View Article and Find Full Text PDFBackground: Extensive exposure to ultraviolet radiation is associated with genetic alterations in basal cell carcinomas (BCCs), which represent some 75% of skin cancers.
Objectives: As recent data suggested the fragile histidine triad (FHIT) gene product to participate in DNA damage responses we wished to address whether functional deletion of this tumour suppressor participates in the development of BCC. Our study focused on epigenetic inactivation of the FHIT gene.
Purpose: The normal human cornea is devoid of both blood and lymphatic vessels and actively maintains this avascularity (corneal angiogenic privilege). Whether and when corneal angiogenic privilege is achieved during development is unknown.
Methods: This study analyzed whether the cornea is primarily devoid of both blood and lymphatic vessels during intrauterine development or whether secondary regression of pre-existing vessels occurs before delivery.
We saw a 62-year-old male with a conjunctival chemosis, which was resistant to local therapy. Excisional biopsy and histological work-up of the tissue were performed. Additional immunohistochemical staining using the Lyve-1 antibody (specific for lymphatic vascular endothelium) allowed the diagnosis of a lymphangioma of the conjunctiva to be made.
View Article and Find Full Text PDFPeriocular sebaceous gland carcinomas (SGCs) occur in the eyelids either sporadically or as a phenotypic feature of Muir-Torre syndrome (MTS). In knockout mice mismatch-repair (MMR) defects or inactivation of the fragile histidine triad (FHIT) gene are associated with MTS-like signs, including SGC. To dissect the genetic alterations associated with microsatellite instability (MSI) and inactivation of the FHIT gene, we studied nine periocular SGC specimens from MTS patients.
View Article and Find Full Text PDFPurpose: To comparatively investigate the effects of TGF-beta(1) and TGF-beta(2) on extracellular matrix production, proliferation, migration, and collagen contraction of cultured human Tenon's capsule fibroblasts derived from patients with pseudoexfoliation (PEX) syndrome, PEX glaucoma, primary open-angle glaucoma (POAG), and cataract.
Methods: Tenon's capsule fibroblasts obtained from four groups of patients were cultured and stimulated with different concentrations (0.1-10 ng ml(-1)) of TGF-beta(1) or TGF-beta(2) for up to 14 days.
Klin Monbl Augenheilkd
October 2001
Background: To evaluate postoperative lens opacifications in foldable hydrophilic intraocular lenses.
Patients And Methods: 12 patients (9 female; 3 male; mean age 77.5 +/- 3 years) were referred from one ophthalmologic surgeon because of opacification of IOLs and markedly decreased visual acuity.