Molecular biology of malignant melanoma

El pdf es la versión post-print.The incidence of melanoma has increased more rapidly than any other type of cancer. In this review, we summarize the most important genetic alterations that contribute to the development of malignant melanoma. Our knowledge of the genetic and biological events involved in the genesis and progression of this disease has been benefited from the evolvement of a wealth of genetically engineered animal models. Hopefully, the understanding generated by all these studies will contribute to develop new therapeutic strategies to handle this fatal malignancy. © 2008 Springer New York.Work in our laboratory has been funded by the Spanish Ministry of Education (grant SAF2004-04902 to MQ) and Fides and Medical Research Funds (grant PI05626 to PM-D). MP is funded by the company Digna Biotech. PM-D is funded by the >Ramón y Cajal> program.Peer Reviewe

Tryptophan concentration is the main mediator of the capacity of adipose mesenchymal stromal cells to inhibit T-lymphocyte proliferation in vitro

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Human adipose tissue–derived mesenchymal stromal cells promote B-cell motility and chemoattraction

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Uveal vs. cutaneous melanoma. Origins and causes of the differences

El pdf del artículo es la versión post-print.-- et al.Melanoma is a malignant tumour derived from melanocytes (dendritic cells originated from the neural crest and capable to produce melanin synthesis) that could be established on the skin or less frequently on the uvea. The cellular origin from both kind of melanoma seems to be the same but the melanocytes migrates to the epithelia for cutaneous melanoma, while for uveal melanoma, they migrate to mesodermic tissues. Despite the common origin, both melanomas show extreme differences in their metastatic potential, clinical response to treatments, immune response and genetic alterations. We will describe some of those differences in this review. © Feseo 2008.Supported by an unrestricted educational grant from GlaxoSmithKline.Peer Reviewe

Comparative Analysis between the In Vivo Biodistribution and Therapeutic Efficacy of Adipose-Derived Mesenchymal Stromal Cells Administered Intraperitoneally in Experimental Colitis

Mesenchymal stem cells (MSCs) have emerged as a promising treatment for inflammatory diseases. The immunomodulatory effect of MSCs takes place both by direct cell-to-cell contact and by means of soluble factors that leads to an increased accumulation of regulatory immune cells at the sites of inflammation. Similar efficacy of MSCs has been described regardless of the route of administration used, the inflammation conditions and the major histocompatibility complex context. These observations raise the question of whether the migration of the MSCs to the inflamed tissues is a pre-requisite to achieve their beneficial effect. To address this, we examined the biodistribution and the efficacy of intraperitoneal luciferase-expressing human expanded adipose-derived stem cells (Luci-eASCs) in a mouse model of colitis. Luci-eASC-infused mice were stratified according to their response to the Luci-eASC treatment. According to the stratification criteria, there was a tendency to increase the bioluminescence signal in the intestine at the expense of a decrease in the bioluminescence signal in the liver in the “responder” mice. These data thus suggest that the accumulation of the eASCs to the inflamed tissues is beneficial for achieving an optimal modulation of inflammation

Adipose Mesenchymal Stromal Cell Function Is Not Affected by Methotrexate and Azathioprine

Given their capacity to modulate the immune response, adipose mesenchymal stem or stromal cells (ASCs) have been used as therapeutic tools to treat chronic inflammatory and autoimmune diseases both in preclinical and clinical studies. Patients enrolled in such clinical trials are often concomitantly treated with immunomodulatory drugs such as methotrexate (MTX) or azathioprine (AZA). Therefore it is necessary to investigate the possible impact of these drugs on ASC function to learn if there are any interactions that would affect the therapeutic effects of either component and thus the clinical outcome of the trials. ASCs were cultured in the absence or presence of MTX or AZA and the effects on viability, proliferation, immunomodulatory properties, and immunogenic features were studied in vitro. The drugs did not affect the viability and proliferative capacity of ASCs. When the drugs and the ASCs were concomitantly used to inhibit lymphocyte proliferation, no synergistic or antagonizing inhibitory effects were found. MTX and AZA did not impair the capacity of ASCs to induce the generation of regulatory T cells in vitro. These data confirm that the immunomodulating features of ASCs are fully functional after exposure to these drugs. Interestingly, whereas MTX did not affect the capacity of natural killer (NK) cells to lyse allogeneic ASCs in vitro, AZA protected allogeneic ASCs from NK cell lysis

Endoscopic submucosal injection of adipose-derived mesenchymal stem cells ameliorates TNBS-induced colitis in rats and prevents stenosis

Abstract Background Mesenchymal stem cells have potential applications in inflammatory bowel disease due to their immunomodulatory properties. Our aim was to evaluate the feasibility, safety and efficacy of endoscopic administration of adipose-derived mesenchymal stem cells (ASCs) in a colitis model in rats. Methods Colitis was induced in rats by rectal trinitrobenzenesulfonic acid (TNBS). After 24 h ASCs (107 cells) or saline vehicle were endoscopically injected into the distal colon. Rats were followed for 11 days. Daily weight, endoscopic score at days 1 and 11, macroscopic appearance at necropsy, colon length and mRNA expression of Foxp3 and IL-10 in mesenteric lymph nodes (MLN) were analyzed. Results Endoscopic injection was successful in all the animals. No significant adverse events or mortality due to the procedure occurred. Weight evolution was significantly better in the ASC group, recovering initial weight by day 11 (− 0.8% ± 10.1%, mean ± SD), whereas the vehicle group remained in weight loss (− 6.7% ± 9.2%, p = 0.024). The endoscopic score improved in the ASC group by 47.1% ± 5.3% vs. 21.8% ± 6.6% in the vehicle group (p < 0.01). Stenosis was less frequent in the ASC group (4.8% vs. 41.2%, p < 0.01). Colon length significantly recovered in the ASC group versus the vehicle group (222.6 ± 17.3 mm vs. 193.6 ± 17.9 mm, p < 0.001). The endoscopic score significantly correlated with weight change, macroscopic necropsy score and colon length. Foxp3 and IL-10 mRNA levels in MLN recovered with ASC treatment. Conclusions ASC submucosal endoscopic injection is feasible, safe and ameliorates TNBS-induced colitis in rats, especially stenosis

Biodistribution and Efficacy of Human Adipose-Derived Mesenchymal Stem Cells Following Intranodal Administration in Experimental Colitis

Mesenchymal stem cells (MSCs) have a large potential in cell therapy for treatment of inflammatory and autoimmune diseases, thanks to their immunomodulatory properties. The encouraging results in animal models have initiated the translation of MSC therapy to clinical trials. In cell therapy protocols with MSCs, administered intravenously, several studies have shown that a small proportion of infused MSCs can traffic to the draining lymph nodes (LNs). This is accompanied with an increase of different types of regulatory immune cells in the LNs, suggesting the importance of migration of MSCs to the LNs in order to contribute to immunomodulatory response. Intranodal (IN), also referred as intralymphatic, injection of cells, like dendritic cells, is being proposed in the clinic for the treatment of cancer and allergy, showing that this route of administration is clinically safe and efficient. In this study, we investigated, for the first time, the biodistribution and the efficacy of Luciferase+ adipose-derived MSCs (Luci-eASCs), infused through the inguinal LNs (iLNs), in normal mice and in inflamed mice with colitis. Most of the Luci-eASCs remain in the iLNs and in the adipose tissue surrounding the inguinal LNs. A small proportion of Luci-eASCs can migrate to other locations within the lymphatic system and to other tissues and organs, having a preferential migration toward the intestine in colitic mice. Our results show that the infused Luci-eASCs protected 58% of the mice against induced colitis. Importantly, a correlation between the response to eASC treatment and a higher accumulation of eASCs in popliteal, parathymic, parathyroid, and mesenteric LNs were found. Altogether, these results suggest that IN administration of eASCs is feasible and may represent an effective strategy for cell therapy protocols with human adipose-derived MSCs in the clinic for the treatment of immune-mediated disorders

Intralymphatic Administration of Adipose Mesenchymal Stem Cells Reduces the Severity of Collagen-Induced Experimental Arthritis

Mesenchymal stem cells (MSCs) are multipotent stromal cells with immunomodulatory properties. They have emerged as a very promising treatment for autoimmunity and inflammatory diseases such as rheumatoid arthritis. Previous studies have demonstrated that MSCs, administered systemically, migrate to lymphoid tissues associated with the inflammatory site where functional MSC-induced immune cells with a regulatory phenotype were increased mediating the immunomodulatory effects of MSCs. These results suggest that homing of MSCs to the lymphatic system plays an important role in the mechanism of action of MSCs in vivo. Thus, we hypothesized that direct intralymphatic (IL) (also referred as intranodal) administration of MSCs could be an alternative and effective route of administration for MSC-based therapy. Here, we report the feasibility and efficacy of the IL administration of human expanded adipose mesenchymal stem cells (eASCs) in a mouse model of collagen-induced arthritis (CIA). IL administration of eASCs attenuated the severity and progression of arthritis, reduced bone destruction and increased the levels of regulatory T cells (CD25+Foxp3+CD4+ cells) and Tr1 cells (IL10+CD4+), in spleen and draining lymph nodes. Taken together, these results indicate that IL administration of eASCs is very effective in modulating established CIA and may represent an alternative treatment modality for cell therapy with eASCs

Additional file 2: of Endoscopic submucosal injection of adipose-derived mesenchymal stem cells ameliorates TNBS-induced colitis in rats and prevents stenosis

Figure S2. The macroscopic damage score correlates with weight change (A) and with endoscopic score (B). (PPTX 2254 kb