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4-Hydroxynonenal (HNE) is the most studied end product of the lipoperoxidation process, by virtue of its relevant biological activity. The antiproliferative and proapoptotic effects of HNE have been widely demonstrated in a great variety of tumor cell types in vitro. Thus, it might represent a promising new molecule in anticancer therapy strategies. However, the extreme reactivity of this aldehyde, as well as its insolubility in water, a limiting factor for drug bioavailability, and its rapid degradation by specific enzymes represent major obstacles to its possible in vivo application. Various strategies can used to overcome these problems. One of the most attractive strategies is the use of nanovehicles, because loading drugs into nanosized structures enhances their stability and solubility, thus improving their bioavailability and their antitumoral effectiveness. Several natural or synthetic polymers have been used to synthesize nanosized structures and, among them, β-cyclodextrin (βCD) polymers are playing a very important role in drug formulation by virtue of the ability of βCD to form inclusion compounds with a wide range of solid and liquid molecules by molecular complexation. Moreover, several βCD derivatives have been designed to improve their physicochemical properties and inclusion capacities. Here we report that the inclusion complex of HNE with a derivative of βCD, the βCD-poly(4-acryloylmorpholine) conjugate (PACM-βCD), enhances the aldehyde stability. Moreover, the inclusion of HNE in PACM-βCD potentiates its antitumor effects in several tumor cell lines and in a more complex system, such as a human reconstructed skin carrying melanoma tumor cells., (© 2013 Elsevier Inc. All rights reserved.)

Background and Purpose: Solid lipid nanoparticles containing cholesteryl butyrate (cholbut SLN) can be a delivery system for the anti-cancer drug butyrate. These nanoparticles inhibit adhesion of polymorphonuclear and tumour cells to endothelial cells and migration of tumour cells, suggesting that they may act as anti-inflammatory and anti-tumour agents. Here we have evaluated the effects of cholbut SLN on tumour cell growth using in vitro and in vivo models., Experimental Approach: Cholbut SLNs were incubated with cultures of four tumour cell lines, and cell growth was analysed by assessing viability, clonogenic capacity and cell cycle. Effects on intracellular signalling was assessed by Western blot analysis of Akt expression. The in vivo anti-tumour activity was measured in two models of PC-3 cell xenografts in SCID/Beige mice., Key Results: Cholbut SLN inhibited tumour cell line viability, clonogenic activity, Akt phosphorylation and cell cycle progression. In mice injected i.v. with PC3-Luc cells and treated with cholbut SLN, . in vivo optical imaging and histological analysis showed no metastases in the lungs of the treated mice. In another set of mice injected s.c. with PC-3 cells and treated with cholbut SLN when the tumour diameter reached 2 mm, analysis of the tumour dimensions showed that treatment with cholbut SLN substantially delayed tumour growth., Conclusion and Implications: Cholbut SLN were effective in inhibiting tumour growth in vitro and in vivo. These effects may involve, in part, inhibition of Akt phosphorylation, which adds another mechanism to the activity of this multipotent drug., (© 2013 The British Pharmacological Society.)

Camptothecin (CPT) is a potent DNA Topoisomerase I inhibitor with anti-tumor activity in hematological and solid tumors. However, it did not reach clinical use because of its poor solubility and high degrability. β-Cyclodextrin nanosponge (CN) have been demonstrated to be able to increase the solubility of lipophilic compounds and to protect them from degradation. In the present study, we evaluated whether β-Cyclodextrin nanosponge carriers can overcome CPT chemical disadvantages and improve the in vitro anti-tumor efficacy in the androgen refractory models of prostate cancer DU145 and PC-3 and the androgen sensitive model LNCaP. Camptothecin-loaded β-Cyclodextrin nanosponge (CN-CPT) showed sizes of about 400 nm, spherical shape and a drug loading of 38%. HPLC analysis, performed on the cell pellet after treatment with CN-CPT revealed that CPT concentration increased over time indicating a prolonged release of the drug. Moreover, CN-CPT inhibited Topoisomerase I activity, and induced DNA damage, and cell cycle arrest more effectively than CPT, indicating that the CN-CPT formulation does not affect activity of the drug. Moreover, Annexin V/Propidium Iodide staining showed an induction of cell death at low concentrations that were not effective for CTP. LNCaP cells were less sensitive to CPT than PC-3 and DU145 cells, but CN-CPT still exerted higher anti-proliferative activity and DNA damage ability than CPT. The experiments performed in LNCaP cells demonstrated that CN-CPT treatment inhibited expression of the androgen receptor at doses where CPT was ineffective. Our results demonstrated the higher anti-tumor effectiveness of CN-CPT compare to CPT in prostate cancer cells, supporting the relevance of future studies for the use of the β-Cyclodextrin nanosponge to deliver anticancer drugs in vivo., (Copyright © 2012 Elsevier B.V. All rights reserved.)

BACKGROUND AND PURPOSE Cholesteryl butyrate solid lipid nanoparticles (cholbut SLN) provide a delivery system for the anti-cancer drug butyrate. These SLN inhibit the adhesion of polymorphonuclear cells to the endothelium and may act as anti-inflammatory agents. As cancer cell adhesion to endothelium is crucial for metastasis dissemination, here we have evaluated the effect of cholbut SLN on adhesion and migration of cancer cells. EXPERIMENTAL APPROACH Cholbut SLN was incubated with a number of cancer cell lines or human umbilical vein endothelial cells (HUVEC) and adhesion was quantified by a computerized micro-imaging system. Migration was detected by the scratch 'wound-healing' assay and the Boyden chamber invasion assay. Expression of ERK and p38 MAPK was analysed by Western blot. Expression of the mRNA for E-cadherin and claudin-1 was measured by RT-PCR. KEY RESULTS Cholbut SLN inhibited HUVEC adhesiveness to cancer cell lines derived from human colon-rectum, breast, prostate cancers and melanoma. The effect was concentration and time-dependent and exerted on both cancer cells and HUVEC. Moreover, these SLN inhibited migration of cancer cells and substantially down-modulated ERK and p38 phosphorylation. The anti-adhesive effect was additive to that induced by the triggering of B7h, which is another stimulus inhibiting both ERK and p38 phosphorylation, and cell adhesiveness. Furthermore, cholbut SLN induced E-cadherin and inhibited claudin-1 expression in HUVEC. CONCLUSION AND IMPLICATIONS These results suggest that cholbut SLN could act as an anti-metastastic agent and they add a new mechanism to the anti-tumour activity of this multifaceted preparation of butyrate., (© 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.)