In uveal melanoma, angiopoietin-2 but not angiopoietin-1 is increased in high-risk tumors, providing a potential druggable target

Simple Summary We hypothesize that proangiogenic factors such as angiopoietin-1 (ANG-1) and angiopoietin-2 (ANG-2), two targetable cytokines, may play a role in tumor development in uveal melanoma. We determined the expression of these cytokines in both uveal melanoma tissue as well as in aqueous humor, which provides a unique combination of data. We observed that ANG-2, in contrast to ANG-1, showed more expression in high-risk tumors and was associated with the development of metastases. Its presence in aqueous humor correlated with expression in tumor tissue. Knowledge about the expression of these cytokines may help to identify targets for personalized treatment. Uveal melanoma (UM) metastasize haematogeneously, and tumor blood vessel density is an important prognostic factor. We hypothesized that proangiogenic factors such as angiopoietin-1 (ANG-1) and angiopoietin-2 (ANG-2), two targetable cytokines, might play a role in tumor development and metastatic behavior. mRNA levels of ANG-1 and ANG-2 were determined in 64 tumors using an Illumina HT-12 v4 mRNA chip and compared to clinical, pathologic, and genetic tumor parameters. Tissue expression was also determined by immunohistochemistry (IHC). Samples of aqueous humor were collected from 83 UM-containing enucleated eyes and protein levels that were determined in a multiplex proximity extension assay. High tissue gene expression of ANG-2, but not of ANG-1, was associated with high tumor thickness, high largest basal diameter, involvement of the ciliary body, and with UM-related death (ANG-2 mRNA p < 0.001; ANG-2 aqueous protein p < 0.001). The presence of the ANG-2 protein in aqueous humor correlated with its mRNA expression in the tumor (r = 0.309, p = 0.03). IHC showed that ANG-2 was expressed in macrophages as well as tumor cells. The presence of ANG-2 in the tumor and in aqueous humor, especially in high-risk tumors, make ANG-2 a potential targetable cytokine in uveal melanoma.Ophthalmic researc

Involvement of mutant and wild-type CYSLTR2 in the development and progression of uveal nevi and melanoma

BackgroundActivating G alpha (q) signalling mutations are considered an early event in the development of uveal melanoma. Whereas most tumours harbour a mutation in GNAQ or GNA11, CYSLTR2 (encoding G-protein coupled receptor CysLT(2)R) forms a rare alternative. The role of wild-type CysLT(2)R in uveal melanoma remains unknown.MethodsWe performed a digital PCR-based molecular analysis of benign choroidal nevi and primary uveal melanomas. Publicly available bulk and single cell sequencing data were mined to further study mutant and wild-type CYSLTR2 in primary and metastatic uveal melanoma.Results1/16 nevi and 2/120 melanomas carried the CYSLTR2 mutation. The mutation was found in a subpopulation of the nevus, while being clonal in both melanomas. In the melanomas, secondary, subclonal CYSLTR2 alterations shifted the allelic balance towards the mutant. The resulting genetic heterogeneity was confirmed in distinct areas of both tumours. At the RNA level, further silencing of wild-type and preferential expression of mutant CYSLTR2 was identified, which was also observed in two CYSLTR2 mutant primary melanomas and one metastatic lesion from other cohorts. In CYSLTR2 wild-type melanomas, high expression of CYSLTR2 correlated to tumour inflammation, but expression originated from melanoma cells specifically.ConclusionsOur findings suggest that CYSLTR2 is involved in both early and late development of uveal melanoma. Whereas the CYSLTR2 p.L129Q mutation is likely to be the initiating oncogenic event, various mechanisms further increase the mutant allele abundance during tumour progression. This makes mutant CysLT(2)R an attractive therapeutic target in uveal melanoma.Ophthalmic researc

Ototopical drops containing a novel antibacterial synthetic peptide: safety and efficacy in adults with chronic suppurative otitis media

ObjectiveChronic suppurative otitis media (CSOM) is a chronic infectious disease with worldwide prevalence that causes hearing loss and decreased quality of life. As current (antibiotic) treatments often unsuccessful and antibiotic resistance is emerging, alternative agents and/or strategies are urgently needed. We considered the synthetic antimicrobial and anti-biofilm peptide P60.4Ac to be an interesting candidate because it also displays anti-inflammatory activities including lipopolysaccharide-neutralizing activity. The aim of the present study was to investigate the safety and efficacy of ototopical drops containing P60.4Ac in adults with CSOM without cholesteatoma.MethodsWe conducted a range-finding study in 16 subjects followed by a randomized, double blinded, placebo-controlled, multicentre phase IIa study in 34 subjects. P60.4Ac-containing ototopical drops or placebo drops were applied twice a day for 2 weeks and adverse events (AEs) and medication use were recorded. Laboratory tests, swabs from the middle ear and throat for bacterial cultures, and audiometry were performed at intervals up to 10 weeks after therapy. Response to treatment was assessed by blinded symptom scoring on otoscopy.ResultsApplication of P60.4Ac-containing ototopical drops (0.25-2.0 mg of peptide/ml) in the ear canal of patients suffering from CSOM was found to be safe and well-tolerated. The optimal dose (0.5 mg of peptide/ml) was selected for the subsequent phase IIa study. Safety evaluation revealed only a few AEs that were unlikely related to study treatment and all, except one, were of mild to moderate intensity. In addition to this excellent safety profile, P60.4Ac ototopical drops resulted in a treatment success in 47% of cases versus 6% in the placebo group.ConclusionThe efficacy/safety balance assessed in the present study provides a compelling justification for continued clinical development of P60.4Ac in therapy-resistant CSOM.Development and application of statistical models for medical scientific researc

Scientific and clinical implications of genetic and cellular heterogeneity in uveal melanoma

Here, we discuss the presence and roles of heterogeneity in the development of uveal melanoma. Both genetic and cellular heterogeneity are considered, as their presence became undeniable due to single cell approaches that have recently been used in uveal melanoma analysis. However, the presence of precursor clones and immune infiltrate in uveal melanoma have been described as being part of the tumour already decades ago. Since uveal melanoma grow in the corpus vitreous, they present a unique tumour model because every cell present in the tumour tissue is actually part of the tumour and possibly plays a role. For an effective treatment of uveal melanoma metastasis, it should be clear whether precursor clones and normal cells play an active role in progression and metastasis. We propagate analysis of bulk tissue that allows analysis of tumour heterogeneity in a clinical setting

Scientific and clinical implications of genetic and cellular heterogeneity in uveal melanoma

Here, we discuss the presence and roles of heterogeneity in the development of uveal melanoma. Both genetic and cellular heterogeneity are considered, as their presence became undeniable due to single cell approaches that have recently been used in uveal melanoma analysis. However, the presence of precursor clones and immune infiltrate in uveal melanoma have been described as being part of the tumour already decades ago. Since uveal melanoma grow in the corpus vitreous, they present a unique tumour model because every cell present in the tumour tissue is actually part of the tumour and possibly plays a role. For an effective treatment of uveal melanoma metastasis, it should be clear whether precursor clones and normal cells play an active role in progression and metastasis. We propagate analysis of bulk tissue that allows analysis of tumour heterogeneity in a clinical setting.Ophthalmic researc

Novel N-heterocyclic ylideneamine gold(i) complexes: Synthesis, characterisation and screening for antitumour and antimalarial activity

Ylideneamine functionalised heterocyclic ligands, 1,3-dimethyl-1,3-dihydro- benzimidazol-2-ylideneamine (I), 3-methyl-3H-benzothiazol-2-ylideneamine (II) or 3,4-dimethyl-3H-thiazol-2-ylideneamine (III), were employed in the preparation of a series of both charged and neutral gold(i) complexes consisting either of a Au(C6F5) fragment (1-3), a [Au(PPh3)] + unit (4-6) or a [Au(NHC)]+ unit (7) coordinated to the imine nitrogen of the neutral ylideneamine ligand. These complexes were fully characterised by various techniques including X-ray diffraction. In addition, the antitumour and antimalarial potential of selected compounds were assessed in a preliminary study aimed at determining the medicinal value of such compounds. Complexation of the azol-2-ylideneamine ligands with [Au(PPh3)] + increases their antitumour as well as antimalarial activity. © 2011 The Royal Society of Chemistry.Articl

A cytotoxic bis(carbene)gold(I) complex of ferrocenyl complexes: Synthesis and structural characterisation

The N-heterocyclic carbene (NHC) precursors 1-[(E)-2-butenyl]-3-(4- ferrocenylphenyl)imidazolium bromide (2) and 1-[(E)-2-butenyl]-3-(4- ferrocenylphenyl)imidazolium tetrafluoroborate (3) were derived from 1-(4-ferrocenylphenyl)imidazole. Ferrocenyl complex 3 reacts with Ag 2O and chloro(dimethylsulfide)gold(i) in the presence of tetraethylammonium chloride to produce the mixed metal species bis{1-[(E)-2-butenyl]-3-(4-ferrocenylphenyl)-2H-imidazol-2-ylidene}gold(i) tetrafluoroborate (4). Single crystal X-ray structure analyses of 1, 3 and 4 indicate that the NCHN-hydrogen in 3 is hydrogen bonded to the BF 4- anion [C(H1)⋯F, 3.265(4) Å], as is also reflected in the position of its 1H NMR chemical shift. Cytotoxicity studies show that complex 4 is selective for cancer cells and active against the tumour cell lines Jurkat and MCF 7. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.The N-heterocyclic carbene (NHC) precursors 1-[(E)-2-butenyl]-3-(4- ferrocenylphenyl)imidazolium bromide (2) and 1-[(E)-2-butenyl]-3-(4- ferrocenylphenyl)imidazolium tetrafluoroborate (3) were derived from 1-(4-ferrocenylphenyl)imidazole. Ferrocenyl complex 3 reacts with Ag 2O and chloro(dimethylsulfide)gold(i) in the presence of tetraethylammonium chloride to produce the mixed metal species bis{1-[(E)-2-butenyl]-3-(4-ferrocenylphenyl)-2H-imidazol-2-ylidene}gold(i) tetrafluoroborate (4). Single crystal X-ray structure analyses of 1, 3 and 4 indicate that the NCHN-hydrogen in 3 is hydrogen bonded to the BF 4- anion [C(H1)⋯F, 3.265(4) Å], as is also reflected in the position of its 1H NMR chemical shift. Cytotoxicity studies show that complex 4 is selective for cancer cells and active against the tumour cell lines Jurkat and MCF 7. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.ArticleArticl

Digital PCR-Based T-cell Quantification-Assisted Deconvolution of the Microenvironment Reveals that Activated Macrophages Drive Tumor Inflammation in Uveal Melanoma

Experimental cancer immunology and therap

Accurate Quantification of T Cells by Measuring Loss of Germline T-Cell Receptor Loci with Generic Single Duplex Droplet Digital PCR Assays

Dermatology-oncolog