Abstract: The invention relates to conjugates in which a sterol is functionalized by an ether bond with a water-soluble polymer to which a guiding ligand is bound. These conjugates improve the physico-chemical and delivery properties of their carrying vesicles, making these more stable, homogeneous and effective. A method for their preparation, a pharmaceutical composition containing said liposomes, and their therapeutic use are described as well.

Abstract: Compounds of formula (I) or their pharmaceutically acceptable salts, or their stereoisomers or mixtures of stereoisomers, where: R1 is selected from the group consisting of: phenyl, and phenyl mono-, di-, or tri-substituted by a radical independently selected from the group consisting of F, Cl, Br, I, (C1-C6)-alkyl, COO—(C1-C6)-alkyl, and (C1-C6)-alkoxy; and R2 is a radical selected from the same group as R1, further including a phenyl substituted in 4-position by a radical independently selected from the group consisting of —O(CH2)CONH(CH2)3CH3 and OCH2COOC(CH3)3, a biphenyl-4-yl, thiazol-2-yl, and a thiazol-2-yl mono- or di-substituted by a radical selected from F and phenyl; inhibit cell proliferation of tumor cells independently of p53 protein and may also induce apoptosis in several tumor cells independently of p53 protein, being useful for the treatment of several types of cancer.

Abstract: Compounds of formula (I) or their pharmaceutically acceptable salts, or their stereoisomers or mixtures of stereoisomers, where: R1 is selected from the group consisting of: phenyl, and phenyl mono-, di-, or tri-substituted by a radical independently selected from the group consisting of F, Cl, Br, I, (C1-C6)-alkyl, COO-(C1-C6)-alkyl, and (C1-C6)-alkoxy; and R2 is a radical selected from the same group as R1, further including a phenyl substituted in 4-position by a radical independently selected from the group consisting of —O(CH2)CONH(CH2)3CH3 and OCH2COOC(CH3)3, a biphenyl-4-yl, thiazol-2-yl, and a thiazol-2-yl mono- or di-substituted by a radical selected from F and phenyl; inhibit cell proliferation of tumor cells independently of p53 protein and may also induce apoptosis in several tumor cells independently of p53 protein, being useful for the treatment of several types of cancer.

Abstract: The method comprising: a) obtaining a gene sequence codifying a naturally occurring aminoacyl-tRNA synthetase; b) engineering the gene codifying for said aminoacyl-tRNA synthetase, resulting into an aminoacyl-tRNA synthetase with a defective activity, with the proviso that the engineering does not affect the functionality of the catalytic site of the enzyme; c) cloning the gene resulting from step (b) in an expression vector; d) transforming isolated mammalian cells with the expression vector resulting from step (c); e) growing the recombinant cells resulting from step (d) in a nutrient medium under conditions which allow the expression of the engineered aminoacyl-tRNA synthetase, resulting the expression into cell death or a decrease in the rate of cell division; f) providing a substance to be tested to the medium resulting from step (e); and g) analyzing the resulting cell growth, wherein if there is an increase in cell growth, then the substance selectively inhibits the activity of the engineered aminoacyl

Abstract: The method comprising: a) obtaining a gene sequence codifying a naturally occurring aminoacyl-tRNA synthetase; b) engineering the gene codifying for said aminoacyl-tRNA synthetase, resulting into an aminoacyl-tRNA synthetase with a defective activity, with the proviso that the engineering does not affect the functionality of the catalytic site of the enzyme; c) cloning the gene resulting from step (b) in an expression vector; d) transforming isolated mammalian cells with the expression vector resulting from step (c); e) growing the recombinant cells resulting from step (d) in a nutrient medium under conditions which allow the expression of the engineered aminoacyl-tRNA synthetase, resulting the expression into cell death or a decrease in the rate of cell division; f) providing a substance to be tested to the medium resulting from step (e); and g) analyzing the resulting cell growth, wherein if there is an increase in cell growth, then the substance selectively inhibits the activity of the engineered aminoacyl

Abstract: A screening method for identifying new drugs A screening method for identifying a candidate to drug wherein said method 5 comprises the following steps: a) obtaining an expression vector which comprises a gene sequence codifying a naturally occurring pathogenic non-discriminating tRNA synthetase; b) transforming isolated mammalian cells with the expression vector; c) growing the recombinant cells resulting from (b) in a nutrient medium under conditions which allow the expression of the 10 pathogenic tRNA synthetase, resulting the expression of the pathogenic tRNA synthetase into cell death or a decrease in the rate of cell division; d) providing a substance to be tested; and e) analyzing the resulting cell growth, wherein if there is an increase in cell growth, then the substance selectively inhibits the activity of the pathogenic tRNA synthetase and does 15 not affect to its cellular ortholog, resulting that said substance is a candidate to drug.