Endoglin is a TGF-beta co-receptor that participates in the activation of a signaling pathway that mediates endothelial cell proliferation and migration in angiogenic tumor vasculature. Therefore, silencing of endoglin expression is an attractive approach for antiangiogenic therapy of tumors. The aim of our study was to evaluate the therapeutic potential of small interfering RNA (siRNA) molecules against endoglin in vitro and in vivo in human and murine endothelial cells and in vivo in TS/A mammary adenocarcinoma growing in BALB/c mice. Results of our study showed that siRNA molecules against endoglin have a good antiangiogenic therapeutic potential in vitro, as expression of endoglin mRNA and protein levels in mouse and human microvascular endothelial cells after lipofection were efficiently reduced, which resulted in the inhibition of endothelial cell proliferation and tube formation. In vivo, silencing of endoglin with triple electrotransfer of siRNA molecules into TS/A mammary adenocarcinoma also significantly reduced the mRNA levels, number of tumor blood vessels and the growth of tumors. The obtained results demonstrate that silencing of endoglin is a promising antiangiogenic therapy of tumors that could be used as an adjunct to the established cytotoxic treatment approaches.
COBISS.SI-ID: 1469819
The data on the biological responsiveness of melanoma and endothelial cells that are targeted by Antiangiogenic MEtargidin Peptide (AMEP) are limited; therefore, the antiproliferative, antimetastatic and antiangiogenic effects of AMEP were investigated in murine melanoma and human endothelial cells after plasmid AMEP gene electrotransfer into the cells in vitro. Plasmid AMEP, a plasmid coding for the disintegrin domain of metargidin targeting specific integrins, had cytotoxic and antiproliferative effects on murine melanoma and human endothelial cells. Among the metastatic properties of cells, migration, invasion and adhesion were investigated. Plasmid AMEP strongly affected the migration of murine melanoma and human endothelial cell lines and also affected the invasion of highly metastatic murine melanoma B16F10 and human endothelial cell lines. There was no effect on cell adhesion on MatrigelTM or fibronectin in all cell lines. The antiangiogenic effect was shown with tube formation assay, where human microvascular endothelial cell line (HMEC-1) proved to be more sensitive to plasmid AMEP gene electrotransfer than the human umbilical vein endothelial cell line (HUVEC). The study indicates that antiproliferative and antimetastatic biological responses to gene electrotransfer of plasmid AMEP in murine melanoma cells were dependent on the integrin quantity on melanoma cells and not on the expression level of AMEP. The strong antiangiogenic effect expressed in human endothelial cell lines was only partly dependent on the quantity of integrins and seemed to be plasmid AMEP dose dependent.
COBISS.SI-ID: 512363065
The melanoma cell adhesion molecule (MCAM) is involved in melanoma development and its progression, including invasiveness, metastatic potential and angiogenesis. Therefore, MCAM represents a potential target for gene therapy of melanoma, whose expression could be hindered with posttranscriptional specific gene silencing with RNA interference technology. In this study, we constructed a plasmid DNA encoding short hairpin RNA against MCAM (pMCAM) to explore the antitumor and antiangiogenic effects. The experiments were performed in vitro on murine melanoma and endothelial cells, as well as in vivo on melanoma tumors in mice. The antiproliferative, antimigratory, antiangiogenic and antitumor effects were examined after gene therapy with pMCAM. Gene delivery was performed by magnetofection, and its efficacy compared to gene electrotransfer. Gene therapy with pMCAM has proved to be an effective approach in reducing the proliferation and migration of melanoma cells, as well as having antiangiogenic effect in endothelial cells and antitumor effect on melanoma tumors. Magnetofection as a developing nonviral gene delivery system was effective in the transfection of melanoma cells and tumors with pMCAM, but less efficient than gene electrotransfer in in vivo tumor gene therapy due to the lack of antiangiogenic effect after silencing Mcam by magnetofection.
COBISS.SI-ID: 1898875
Electroporation-electropermeabilization, i.e. the result of the application of electric pulses to tissues, is a physical method for delivery of exogenous molecules into cells. It is effective particularly for compounds with limited transmembrane transport. In vivo, electropermeabilization facilitates the delivery of chemotherapeutic drugs into tumor cells that is the basic mechanism of the antitumor effectiveness of electrochemotherapy. This therapy has also blood flow modifying effects in tissues. The aim of our present study was to understand and explain the effects of electropermeabilization on the dynamics (vasomotricity, permeability and recovery) of subcutaneous blood vessels towards different size of molecules. These features were measured in C57Bl/6 mice via a dorsal skin fold window chamber, using fluorescently labeled dextrans of different sizes, intravital fluorescence microscopy imaging and specific image analysis. Application of electric pulses on the skin in vivo resulted in a rapid increase in vascular permeability that gradually recovered to basal levels at different times post-treatment, depending on dextran size. Simultaneously, the immediate constriction of the blood vessels occurred that was more pronounced for arterioles compared to venules. This vasoconstriction of arterioles results in a transient vascular lock. The increased permeability of small vessels walls whatever the dextran size associated with delazed perfusion explains the improved delivery of the intravenous injected molecules (i.e. drugs, gene delivery) into the tissues induced by electropermeabilization in vivo.
COBISS.SI-ID: 1348475
Magnetofection is a nanoparticle-mediated approach for transfection of cells, tissues, and tumors. Specific interest is in using superparamagnetic iron oxide nanoparticles (SPIONs) as delivery system of therapeutic genes. Magnetofection has already been described in some proof-of-principle studies; however, fine tuning of the synthesis of SPIONs is necessary for its broader application. Physicochemical properties of SPIONs, synthesized by the co-precipitation in an alkaline aqueousmedium, were tested after varying different parameters of the synthesis procedure.The storage time of iron(II) sulfate salt, the type of purified water, and the synthesis temperature did not affect physicochemical properties of SPIONs. Also, varying the parameters of the synthesis procedure did not influence magnetofection efficacy. However, for the pronounced gene expression encoded by plasmid DNA it was crucial to functionalize poly(acrylic) acid-stabilized SPIONs (SPIONs-PAA) with polyethyleneimine (PEI) without the adjustment of its elementary alkaline pH water solution to the physiological pH. In conclusion, the co-precipitation of iron(II) and iron(III) sulfate salts with subsequent PAA stabilization, PEI functionalization, and plasmid DNA binding is a robust method resulting in a reproducible and efficient magnetofection. To achieve high gene expression is important, however, the pH of PEI water solution for SPIONs-PAA functionalization, which should be in the alkaline range.
COBISS.SI-ID: 1530491