Structure, unique biological properties, and mechanisms of action of transforming growth factor ß.

Transforming growth factor ß (TGF-ß) is a ubiquitous molecule that is extremely conserved structurally and plays a systemic role in human organism. TGF-ß is a homodimeric molecule consisting of two subunits joined through a disulphide bond. In mammals, three genes code for TGF-ß1, TGF-ß2, and TGF-ß3 isoforms of this cytokine with a dominating expression of TGF-ß1. Virtually, all normal cells contain TGF-ß and its specific receptors. Considering the exceptional role of fine balance played by the TGF-ß in anumber of physiological and pathological processes in human body, this cytokine may be proposed for use in medicine as an immunosuppressant in transplantology, wound healing and bone repair. TGFb itself is an important target in oncology. Strategies for blocking members of TGF-ß signaling pathway as therapeutic targets have been considered. In this review, signalling mechanisms of TGF-ß1 action are addressed, and their role in physiology and pathology with main focus on carcinogenesis are described.

Thiopyrano[2,3-d]thiazole structures as promising scaffold with anticancer potential.

Seven chromeno[4',3':4,5]thiopyrano[2,3-d]thiazole derivatives were synthesized and screened for their cytotoxic effects on different lines of mammalian leukemia, breast adenocarcinoma, glioblastoma, and pseudo-normal and normal cells. The derivative 3 demonstrated toxicity towards tumor cells of Jurkat, K562, U251, HL-60, MCF-7, and MDA-MB-231 lines. At the same time, this compound possessed low toxicity (IC50 > 100 µM) towards cells, used as control, representing non-tumor, somatic cells: HaCaT, HEK293 cells as well as murine Balb/c 3T3 and J774.2 cells, mink Mv1Lu cells, and normal mitogen-activated human blood lymphocytes. The derivative 3 induced apoptosis in human leukemia Jurkat T-cells and glioblastoma U251 cells via mitochondria-dependent pathway and inhibition of the DNA reparation enzyme PARP-1. This compound triggered pro-apoptotic morphological changes in Jurkat and U251 cells, namely chromatin condensation, nuclei fragmentation, and membrane blebbing. However, the DNA damaging effects of compound 3 were significantly lower in normal human lymphocytes, compared with such results in tumor Jurkat and U251 cells. The DNA damaging effects of compound 3 were unrelated to its DNA-binding and/or DNA-intercalating abilities. This compound induced the accumulation of endogenous reactive oxygen species (ROS), namely superoxide radicals, in human leukemia and glioblastoma cells. Our finding indicated that compound 3 inhibited the viability of human leukemia T-cells and glioblastoma cells via induction of DNA damage and apoptosis through ROS-mediated mitochondrial pathway.

Synthesis and antitrypanosomal activity of new 6,6,7-trisubstituted thiopyrano[2,3-d][1,3]thiazoles.

А series of novel 6,6,7-trisubstituted thiopyrano[2,3-d][1,3]thiazoles-based molecules have been synthesized and evaluated as potential antitrypanosomal agents. The most active analogue 3b inhibited Trypanosoma brucei brucei and Trypanosoma brucei gambiense with an IC(50) of 0.26 and 0.42 µÐœ, respectively. They could be considered as potent hits for further antitrypanosomal drug discovery efforts.