Our results demonstrate that MT may represent a suitable prognostic factor that can characterize the metastasising ability of CMM and the tumour-promoting host immune response.

UVB irradiation induces harmful photochemical reactions, including formation of cyclobutane pyrimidine dimers (CPDs) in DNA. Accumulation of unrepaired CPD lesions causes inflammation, premature ageing and skin cancer. Photolyases are DNA repair enzymes that can rapidly restore DNA integrity in a light-dependent process called photoreactivation, but these enzymes are absent in humans. Here, we present a novel mRNA-based gene therapy method that directs synthesis of a marsupial, Potorous tridactylus, CPD-photolyase in cultured human keratinocytes. Pseudouridine was incorporated during in vitro transcription to make the mRNA non-immunogenic and highly translatable. Keratinocytes transfected with lipofectamine-complexed mRNA expressed photolyase in the nuclei for at least 2 days. Exposing photolyase mRNA-transfected cells to UVB irradiation resulted in significantly less CPD in those cells that were also treated with photoreactivating light, which is required for photolyase activity. The functional photolyase also diminished other UVB-mediated effects, including induction of IL-6 and inhibition of cell proliferation. These results demonstrate that pseudouridine-containing photolyase mRNA is a powerful tool to repair UVB-induced DNA lesions. The pseudouridine-modified mRNA approach has a strong potential to discern cellular effects of CPD in UV-related cell biological studies. The mRNA-based transient expression of proteins offers a number of opportunities for future application in medicine.

Zinc is an essential microelement; its importance to skin is shown by severe skin symptoms in hereditary or acquired zinc deficiency, by the improvement of several skin conditions using systemic or topical zinc preparations and by the induced intracellular zinc release upon UVB exposure, which is the main harmful environmental factor to skin. Understanding the molecular background of the role of zinc in skin may help to gain insight into the pathology of skin disorders and to provide evidence for the therapeutic usefulness of zinc supplementation.Herein, we studied the effect of zinc chloride (ZnCl 2 ) exposure on the function of HaCaT keratinocytes, and we found that a non-toxic elevation in the concentration of extracellular zinc (100 µM) facilitated cell proliferation and induced significant alterations in the mRNA expression of NOTCH1, IL8, and cyclooxygenase-2. In addition, we detected increased heme oxygenase-1 (HMOX1) expression and non-toxic generation of superoxide in the first 4 h.Regarding the effect on UVB-induced toxicity, although the level of cyclobutane pyrimidine dimers in keratinocytes pre-treated with zinc for 24 h was reduced 3 h after UVB irradiation, we found significantly enhanced superoxide generation 10 h after UVB exposure in the zinc pre-exposed cells. The overall survival was unaffected; however, there was a decrease in the percentage of early apoptotic cells and an increase in the percentage of late apoptotic plus necrotic cells.Our results suggest that exposure of human keratinocytes to non-toxic concentrations of ZnCl 2 impacts gene expression, cell proliferation and the response to environmental stress in skin. It would be important to further examine the role of zinc in skin and to further clarify if this issue can affect our thinking about the pathogenesis of skin diseases.

Aim: The purpose of this study was to develop a folate receptor-targeted 68 Ga-labeled agent for the detection of cancer cells in mouse models of ovarian cancer by dual positron-emission tomography (PET) and magnetic resonance imaging (MRI). Moreover, we aimed to develop a controlled biopolymer-based chemistry that enables linking metal-binding (here Ga-68) chelators. Materials and Methods: The nanoparticle (NP) agent was created by self-assembling of folic acid-modified polyglutamic acid and chelator-modified chitosan followed by radiolabeling with 68 Ga (III) ions ( 68 Ga-NODAGA-FA). The structure of modified biopolymers was characterized by spectroscopy. Particle size and mobility were determined. Results: Significant selective binding of NPs was established in vitro using folate receptor-positive KB andnegative MDA-MB-231 cell lines. In vivo tumor uptake of folate-targeted 68 Ga 3+ -radiolabeled NPs was tested using subcutaneous tumor-bearing CB17 SCID mice models. PET/MR dual modalities showed high tumor uptake with In vivo results supporting the preliminary in vitro tests demonstrated considerably higher 68 Ga-NODAGA-FA nanoparticle accumulation in KB tumors than in MDA-MB-231 tumors, thereby confirming the folate receptor-mediated uptake of this novel potential PET imaging agent.