Abstract: The present invention provides methods of utilizing a nucleoside derivative having the chemical formula of Formula (I) to downregulate expression of an anti-apoptotic protein such as survivin in a cell, induce apoptosis in a cell, inhibit angiogenesis in a cell, inhibit binding of p53 to DNA in a cell, inhibit phosphorylation of Akt in a cell and inhibit HIV transcription in a cell, by administering to the cell or tissue an amount of a compound of Formula (I) sufficient to achieve the desired activity. Formula (I): wherein the substituents Ra, Rb, Rc, Rd, Re, Rf, Rg, Rh, Ri and Rk are as defined in the specification. A particularly preferred nucleoside derivative is ARC (4-amino-6-hydrazino-7-beta-D-ribofuranosyl-7H-pyrrolo[2,3-d]-pyrimidine-5-carboxamide).

Abstract: This invention provides methods and pharmaceutical compositions for regulating cell growth or inducing apoptosis in a cell, particularly a mammalian tumor cell. Specifically, the invention provides methods for inducing apoptosis in a tumor cell comprising contacting the tumor cell with a proteasome inhibitor and a thiazole antibiotic, particularly each in a suboptimal amount.

Abstract: The present invention provides methods of utilizing a nucleoside derivative having the chemical formula of Formula (I) to downregulate expression of an anti-apoptotic protein such as survivin in a cell, induce apoptosis in a cell, inhibit angiogenesis in a cell, inhibit binding of p53 to DNA in a cell, inhibit phosphorylation of Akt in a cell and inhibit HIV transcription in a cell, by administering to the cell or tissue an amount of a compound of Formula (I) sufficient to achieve the desired activity. Formula (I): wherein the substituents Ra, Rb, Rc, Rd, Re, Rf, Rg, Rh, Ri and Rk are as defined in the specification. A particularly preferred nucleoside derivative is ARC (4-amino-6-hydrazino-7-beta-D-ribofuranosyl-7H-pyrrolo[2,3-d]-pyrimidine-5-carboxamide).