Interleukin-8 in Melanoma Pathogenesis, Prognosis and Therapy-An Integrated View into Other Neoplasms and Chemokine Networks.

Cutaneous melanoma accounts for only about 7% of skin cancers but is causing almost 90% of deaths. Melanoma cells have a distinct repertoire of mutations from other cancers, a high plasticity and degree of mimicry toward vascular phenotype, stemness markers, versatility in evading and suppress host immune control. They exert a significant influence on immune, endothelial and various stromal cells which form tumor microenvironment.

Interaction Analysis of Commercial Graphene Oxide Nanoparticles with Unicellular Systems and Biomolecules.

The ability of commercial monolayer graphene oxide (GO) and graphene oxide nanocolloids (GOC) to interact with different unicellular systems and biomolecules was studied by analyzing the response of human alveolar carcinoma epithelial cells, the yeast and the bacteria to the presence of different nanoparticle concentrations, and by studying the binding affinity of different microbial enzymes, like the α-l-rhamnosidase enzyme RhaB1 from the bacteria and the AbG β-d-glucosidase from sp. (strain ATCC 21400). An analysis of cytotoxicity on human epithelial cell line A549, (colony forming units, ROS induction, genotoxicity) and (luminescence inhibition) cells determined the potential of both nanoparticle types to damage the selected unicellular systems.

Variations in the expression of TIMP1, TIMP2 and TIMP3 in cutaneous melanoma with regression and their possible function as prognostic predictors.

Regression in melanoma is a frequent biological event of uncertain prognostic value as the lesion exhibits heterogeneous phenotypical features, both at the morphological and immunohistochemical level. In the present study, we examined the expression of tissue inhibitors of metalloproteinases (TIMP1, TIMP2 and TIMP3) in melanoma with regression. We specifically examined the expression levels of these TIMPs in regressed components (RC) and non-regressed components (NRC) of the tumor and compared their expression levels with those in non-regressed melanomas.

Cross-talk between Dopachrome Tautomerase and Caveolin-1 Is Melanoma Cell Phenotype-specific and Potentially Involved in Tumor Progression.

l-Dopachrome tautomerase (l-DCT), also called tyrosinase-related protein-2 (TRP-2), is a melanoma antigen overexpressed in most chemo-/radiotherapeutic stress-resistant tumor clones, and caveolin-1 (CAV1) is a main regulator of numerous signaling processes. A structural and functional relationship between DCT and CAV1 is first presented here in two human amelanotic melanoma cell lines, derived from vertical growth phase (MelJuSo) and metastatic (SKMel28) melanomas. DCT co-localizes at the plasma membrane with CAV1 and Cavin-1, another molecular marker for caveolae in both cell phenotypes.

Value of dopachrome tautomerase detection in the assessment of melanocytic tumors.

Dopachrome tautomerase (DCT) and tyrosinase (Tyr) are melanogenic enzymes and structurally related melanosomal proteins. The present study investigates DCT expression comparatively with Tyr, the most tested melanoma biomarker, aiming to evaluate DCT potential in the assessment of melanocytic tumors and gain insights into the molecular and pathological characterization of DCT-phenotype in tumor progression. DCT and Tyr are simultaneously analyzed in melanoma cell lines by semiquantitative RT-PCR, western blot, and N-glycan analysis, and in cell populations of melanocytic tumors by immunohistofluorescence using a novel anti-hDCT antibody against an extended sequence within DCT luminal domain.

Spectrum of morphologic alterations of regression in cutaneous melanoma--potential for improving disease prognosis.

Introduction: Regression occurs as a complex interaction between tumor cells and host's immune response; neither biologic mechanisms, nor regression prognostic significance are deciphered to date but promising anti-cancer vaccine strategies were thus developed.

Methods: We analyzed 127 superficial spreading melanomas identifying melanoma with regression (segmentary (SR), partial (PR) and segmentary & partial (SR-PR)) or without regression (AR). Several histopathologic parameters were registered; statistical analysis was performed (level of significance P < 0.

Internalization and intracellular trafficking of poly(propylene imine) glycodendrimers with maltose shell in melanoma cells.

The diagnosis and treatment of malignant melanoma by means of the formulation of active principles with dendrimeric nanoparticles is an area of great current interest. The identification and understanding of molecular mechanisms which ensure the integration of particular dendrimeric nanostructures in tumor cellular environment can provide valuable guidance in their coupling strategies with antitumor or diagnostic agents. Two structurally distinct maltose-shell modified 5th generation (G5) poly(propylene imine) (PPI) glycodendrimers fluorescently labeled, (a) with open maltose shell, cationic charged G5-PPI-OS and (b) with dense maltose shell and nearly neutral G5-PPI-DS, were tested in relation with several melanoma cell lines.

Specific biofunctional performances of the hydroxyapatite-sodium maleate copolymer hybrid coating nanostructures evaluated by in vitro studies.

The nanohybrid structures consisting of hydroxyapatite (HA) and sodium maleate-vinyl acetate copolymer (MP) deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique on Ti surfaces were investigated for specific biological qualities required in bone implantology. The data from in vitro studies demonstrated that human primary osteoblasts (OBs) firmly adhered to Ti coated with HA-MP as indicated by cytoskeleton and vinculin dynamics. OBs spread onto biomaterial surface and formed groups of cells which during their biosynthetic activity expressed OB phenotype specific markers (collagen and non-collagenous proteins) and underwent controlled proliferation.

Cutaneous metastases of malignant melanoma--how difficult can it be?

Malignant melanoma is one of the most aggressive skin neoplasms with histopathological-based therapeutic approach. Unfortunately, in some cases, even the elementary issue of dealing with a primary or metastatic lesion may be sometimes incredible difficult to settle. We studied 11 cases of malignant melanomas that required careful histopathological and immunohistochemical analysis to differentiate between primary and secondary tumor.

Biocompatibility evaluation of a novel hydroxyapatite-polymer coating for medical implants (in vitro tests).

Nanocomposites consisting of hydroxyapatite (HA) and a sodium maleate copolymer (maleic polyelectrolyte), synthesized by hydrothermal method and deposited on titanium substrates by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique were tested for the biological properties. Coating bioanalysis was carried out by triple staining of actin, microtubules and nuclei followed by immunofluorescence microscopy. Within 24 h cells that occupied the biomaterial surface displayed the morphology and cytoskeleton pattern similar to the controls.

Tyrosinase-related protein-2 and -1 are trafficked on distinct routes in B16 melanoma cells.

Tyrosinase related protein (TRP)-1 and -2 regulate the main steps in melanin synthesis and are immune targets in skin cancer or autoimmune pigmentary disorders. We found that ionophore monensin (Mon) and the quaternary amine chloroquine (CQ) discriminate between the traffic routes of TRP-2 and TRP-1. TRP-2 N-glycan processing is interrupted by Mon between ER and trans-Golgi, whereas this process continues for TRP-1.

Munc13-4 is an effector of rab27a and controls secretion of lysosomes in hematopoietic cells.

Griscelli syndrome type 2 (GS2) is a genetic disorder in which patients exhibit life-threatening defects of cytotoxic T lymphocytes (CTLs) whose lytic granules fail to dock on the plasma membrane and therefore do not release their contents. The disease is caused by the absence of functional rab27a, but how rab27a controls secretion of lytic granule contents remains elusive. Mutations in Munc13-4 cause familial hemophagocytic lymphohistiocytosis subtype 3 (FHL3), a disease phenotypically related to GS2.

The inhibition of early N-glycan processing targets TRP-2 to degradation in B16 melanoma cells.

Tyrosinase-related protein-2 (TRP-2) is a DOPAchrome tautomerase catalyzing a distal step in the melanin synthesis pathway. Similar to the other two melanogenic enzymes belonging to the TRP gene family, tyrosinase and TRP-1, TRP-2 is expressed in melanocytes and melanoma cells. Despite the increasing evidence of its efficiency as a melanoma antigen, little is known about the maturation and intracellular trafficking of TRP-2.

Folding and maturation of tyrosinase-related protein-1 are regulated by the post-translational formation of disulfide bonds and by N-glycan processing.

In this study we have explored the endoplasmic reticulum associated events accompanying the maturation of the tyrosinase-related protein-1 (TRP-1) nascent chain synthesized in mouse melanoma cells. We show that TRP-1 folding process occurs much more rapidly than for tyrosinase, a highly homologous protein, being completed post-translationally by the formation of critical disulfide bonds. In cells pretreated with dithiothreitol (DTT), unfolded TRP-1 is retained in the endoplasmic reticulum by a prolonged interaction with calnexin and BiP before being targeted for degradation.

Mutations at critical N-glycosylation sites reduce tyrosinase activity by altering folding and quality control.

Tyrosinase is a copper-containing enzyme that regulates melanin biosynthesis in mammals. Mutations at a single N-glycosylation sequon of tyrosinase have been reported to be responsible for oculocutaneous albinism type IA in humans, characterized by inactive tyrosinase and the total absence of pigmentation. To probe the role that each N-glycosylation site plays in the synthesis of biologically active tyrosinase, we analyzed the calnexin mediated folding of tyrosinase N-glycosylation mutants.

Investigation of the intracellular transport of tyrosinase and tyrosinase related protein (TRP)-1. The effect of endoplasmic reticulum (ER)-glucosidases inhibition.

Melanin biosynthesis is completely inhibited in the B16 melanoma cells following their incubation with inhibitors of the two ER glucosidases. This is primarily due to the inactivation of tyrosinase. Under the same conditions, the DOPA-oxidase activity of TRP-1 was only partially affected.

Protein specific N-glycosylation of tyrosinase and tyrosinase-related protein-1 in B16 mouse melanoma cells.

Tyrosinase and tyrosinase-related protein-1 (TRP-1) are two melanogenic enzymes that regulate melanin biosynthesis. Both are glycoproteins and belong to the TRP-1 gene family. They share a significant level of sequence similarity in several regions, including the catalytic domain and the potential N-glycosylation sites.

Critical roles of glycosaminoglycan side chains of cartilage proteoglycan (aggrecan) in antigen recognition and presentation.

Systemic immunization of BALB/c mice with proteoglycan (aggrecan) from fetal human cartilage induces progressive polyarthritis, an experimental disease similar to human rheumatoid arthritis. The development of the disease in this genetically susceptible murine strain is based on cross-reactive immune responses between the immunizing fetal human and mouse self-proteoglycans. One of the cross-reactive and arthritogenic T cell epitopes (92GR/QVRVNSA/IY) is localized in the G1 domain of human/murine proteoglycan.

Antigen-specific B cells present cartilage proteoglycan (aggrecan) to an autoreactive T cell hybridoma derived from a mouse with proteoglycan-induced arthritis.

Cartilage proteoglycan (aggrecan)-induced polyarthritis in BALB/c mice is characterized by chronic inflammation and destruction of joint tissues similar to that observed in human rheumatoid arthritis. The immunization of mice with fetal human proteoglycan (PG) elicits specific antibodies to the immunizing antigen of which a population cross-reacts with native mouse PG. This (auto)antibody production is immediately followed by an explosive proliferation of autoreactive T cells, suggesting that PG-specific B cells may participate in antigen presentation of PG to autoreactive T cells.

A proteoglycan (aggrecan)-specific T cell hybridoma induces arthritis in BALB/c mice.

Aggrecan, the high buoyant density cartilage proteoglycan (PG), has been shown to induce progressive polyarthritis and ankylosing spondylitis in genetically susceptible BALB/c mice. To further characterize the nature of the autopathogenic effector T cells operating in these mice and to determine the region(s) of the PG molecule recognized by these T cells, we generated PG-specific T cell hybridomas from arthritic mice. One of the PG-specific T cell hybridomas (5/4E8), when injected into naive irradiated BALB/c mice, was capable of inducing clinical and histopathologic signs of arthritis.

Presentation of cartilage proteoglycan to a T cell hybridoma derived from a mouse with proteoglycan-induced arthritis.

Immunization of BALB/c mice with human fetal cartilage proteoglycan (PG) produces progressive polyarthritis, and T cells play key roles in the development of the disease. To gain an understanding of how PG is presented to autoreactive T cells by synovial antigen-presenting cells (APC), we examined the abilities of various syngeneic APC in presenting PG to a specific T cell hybridoma 5/4E8, derived from a mouse with PG-induced arthritis. A20 B lymphoma cells and spleen cells were strong presenters of PG, but synoviocytes and P388D1 macrophages could only present PG effectively after stimulation with interferon-gamma (IFN-gamma).

The action of the collagen-Fe2+ complex at tissular level.

The aim of this paper is to know the iron dynamics and action of the collagen-Fe2+ complex at tissular level. The results showed that the collagen-Fe2+ complex is biocompatible at tissular level and the ferrous iron entered the animal organism on the well-known metabolic pathways. When a high dose of the complex was administered, an overloading with hemosiderin of macrophages and hepatocytes was noticed.