Targeting melanoma stem cells with the Vitamin E derivative δ-tocotrienol

The prognosis of metastatic melanoma is very poor, due to the development of drug resistance. Cancer stem cells (CSCs) may play a crucial role in this mechanism, contributing to disease relapse. We first characterized CSCs in melanoma cell lines. We observed that A375 (but not BLM) cells are able to form melanospheres and show CSCs traits: expression of the pluripotency markers SOX2 and KLF4, higher invasiveness and tumor formation capability in vivo with respect to parental adherent cells. We also showed that a subpopulation of autofluorescent cells expressing the ABCG2 stem cell marker is present in the A375 spheroid culture. Based on these data, we investigated whether \uce\ub4-TT might target melanoma CSCs. We demonstrated that melanoma cells escaping the antitumor activity of \uce\ub4-TT are completely devoid of the ability to form melanospheres. In contrast, cells that escaped vemurafenib treatment show a higher ability to form melanospheres than control cells. \uce\ub4-TT also induced disaggregation of A375 melanospheres and reduced the spheroidogenic ability of sphere-derived cells, reducing the expression of the ABCG2 marker. These data demonstrate that \uce\ub4-TT exerts its antitumor activity by targeting the CSC subpopulation of A375 melanoma cells and might represent a novel chemopreventive/therapeutic strategy against melanoma

Dual targeting of tumor and endothelial cells by Gonadotropin-Releasing Hormone agonists to reduce melanoma angiogenesis

We previously showed that GnRH receptors are expressed in melanoma cells; their activation reduces the cell growth and metastatic behavior. Here, we investigated whether GnRH agonists might affect the expression of genes involved in melanoma progression. By genome wide transcriptomic and by Real Time PCR analysis we first observed that GnRH agonists decrease the expression of the pro-angiogenic factor VEGF (all isoforms) in BLM melanoma cells. Then, we demonstrated that GnRH agonists specifically decrease the expression of the VEGF165 isoform as well as its secretion from BLM cells. These data suggested that activation of GnRH receptors might reduce the pro-angiogenic behavior of melanoma cells. To verify this hypothesis we treated BLM cells with a GnRH agonist; the conditioned medium from these cells was tested to assess its capability to stimulate HUVEC cells motility. The migration of HUVEC cells towards the conditioned medium of GnRH agonist-treated BLM cells was significantly lower than the migration of HUVEC cells towards the conditioned medium of untreated cells. Thus, GnRH agonists reduce the pro-angiogenic behavior of melanoma cells through a decreased production of VEGF. We then found that GnRH receptors are also expressed on HUVEC cells and that GnRH agonists reduce their ability to proliferate and to form capillary-like tubes when stimulated by VEGF. These findings suggest that GnRH agonists exert anti-angiogenic activity indirectly, by decreasing VEGF secretion from tumor cells, and directly, by counteracting the pro-angiogenic activity of the growth factor. These data might lead to the development of novel targeted approaches for melanoma

Gene expression correlating with response to paclitaxel in ovarian carcinoma xenografts

Molecular Cancer Therapeutics32111-121MCTO

Carbon based nanomaterials for tissue engineering of bone: Building new bone on small black scaffolds: A review

Tissue engineering is a rapidly-growing approach to replace and repair damaged and defective tissues in the human body. Every year, a large number of people require bone replacements for skeletal defects caused by accident or disease that cannot heal on their own. In the last decades, tissue engineering of bone has attracted much attention from biomedical scientists in academic and commercial laboratories. A vast range of biocompatible advanced materials has been used to form scaffolds upon which new bone can form. Carbon nanomaterial-based scaffolds are a key example, with the advantages of being biologically compatible, mechanically stable, and commercially available. They show remarkable ability to affect bone tissue regeneration, efficient cell proliferation and osteogenic differentiation. Basically, scaffolds are templates for growth, proliferation, regeneration, adhesion, and differentiation processes of bone stem cells that play a truly critical role in bone tissue engineering. The appropriate scaffold should supply a microenvironment for bone cells that is most similar to natural bone in the human body. A variety of carbon nanomaterials, such as graphene oxide (GO), carbon nanotubes (CNTs), fullerenes, carbon dots (CDs), nanodiamonds and their derivatives that are able to act as scaffolds for bone tissue engineering, are covered in this review. Broadly, the ability of the family of carbon nanomaterial-based scaffolds and their critical role in bone tissue engineering research are discussed. The significant stimulating effects on cell growth, low cytotoxicity, efficient nutrient delivery in the scaffold microenvironment, suitable functionalized chemical structures to facilitate cell-cell communication, and improvement in cell spreading are the main advantages of carbon nanomaterial-based scaffolds for bone tissue engineering. © 201

Low-level Laser Therapy To The Mouse Femur Enhances The Fungicidal Response Of Neutrophils Against Paracoccidioides Brasiliensis

Neutrophils (PMN) play a central role in host defense against the neglected fungal infection paracoccidioidomycosis (PCM), which is caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb). PCM is of major importance, especially in Latin America, and its treatment relies on the use of antifungal drugs. However, the course of treatment is lengthy, leading to side effects and even development of fungal resistance. The goal of the study was to use low-level laser therapy (LLLT) to stimulate PMN to fight Pb in vivo. Swiss mice with subcutaneous air pouches were inoculated with a virulent strain of Pb or fungal cell wall components (Zymosan), and then received LLLT (780 nm; 50 mW; 12.5 J/cm2; 30 seconds per point, giving a total energy of 0.5 J per point) on alternate days at two points on each hind leg. The aim was to reach the bone marrow in the femur with light. Non-irradiated animals were used as controls. The number and viability of the PMN that migrated to the inoculation site was assessed, as well as their ability to synthesize proteins, produce reactive oxygen species (ROS) and their fungicidal activity. The highly pure PMN populations obtained after 10 days of infection were also subsequently cultured in the presence of Pb for trials of protein production, evaluation of mitochondrial activity, ROS production and quantification of viable fungi growth. PMN from mice that received LLLT were more active metabolically, had higher fungicidal activity against Pb in vivo and also in vitro. The kinetics of neutrophil protein production also correlated with a more activated state. LLLT may be a safe and non-invasive approach to deal with PCM infection

In Vitro Rumen Fermentation Characteristics of Some Naturally Occurring and Synthetic Sugars

Soluble sugars are thought to play an important role in the fermentation processes of the rumen but their actual fermentation rate has not been fully assessed. Some sugars are also used as markers to assess gut permeability in monogastrics but their use in ruminants can be compromised by the hydrolytic activity of rumen microflora. This study aimed to evaluate the fermentability of some naturally occurring and synthetic soluble sugars. The synthetic soluble sugars were included to verify their possible use as markers for studies of gut permeability in ruminants. In vitro gas and volatile fatty acid (VFA) production from glucose, fructose, xylose, galactose, sucrose, lactose, arabinose mannitol, lactulose and sucralose were measured in a 24 h-incubation trial using ruminal fluid from heifers adapted or not-adapted to additional sugars in the diet, and with caecal content as inocula. Gas production from the same sugars was further evaluated in a 72 h-incubation trial with not-adapted rumen fluid only. Gas and VFA production were not affected by feeding additional sugars, but significant effects of inocula (ruminal vs caecal), sugars and their interaction were observed. Caecal inoculum produced less gas but higher VFA than ruminal inocula. Fructose and glucose had the highest rates of gas production (10.57% h-1 and 10.42% h-1, respectively), and lactulose and mannitol the lowest (3.47% h-1 and 4.63% h-1, respectively) when fermented with ruminal fluid. Sucralose seemed to have a negative effect on microbial fermentations. Our results indicate that lactulose and mannitol might largely escape rumen fermentation, suggesting their possible use as markers to test gut permeability also in ruminants. This needs to be verified in vivo