Synthesis, characterization, crystal structures and biological activity of set of Cu(II) benzothiazole complexes: artificial nucleases with cytotoxic activities.

A series of Cu(II) complexes with ligand frames based on quinoline derivatives appended with a benzothiazole substituent has been isolated. The complexes, Cu(Q(oBt))(NO3)2(H2O)∙CH3OH (1∙CH3OH), Cu(8OHQ(oBt))Cl2∙CH3OH (2∙CH3OH), Cu(8OQ(oBt))Cl(CH3OH)∙CH3OH (3∙CH3OH) and [Cu(8OH1/2Q(oBt))(CH3OH)(NO3)]2(NO3) (4) have been characterized by single crystal X-ray diffraction, IR and UV-visible spectroscopies, and elemental analysis. The ligand frame within the set of complexes differs in the substituent on the quinoline ring: complex 1 remains unsubstituted at this position while complexes 2-4 have a substituted OH group.

The microtubule cytoskeleton is required for a G2 cell cycle delay in cancer cells lacking stathmin and p53.

In several cancer cell lines, depleting the microtubule (MT)-destabilizing protein stathmin/oncoprotein18 leads to a G2 cell cycle delay and apoptosis. These phenotypes are observed only in synergy with low levels of p53, but the pathway(s) activated by stathmin depletion to delay the cell cycle are unknown. We found that stathmin depletion caused greater MT stability in synergy with loss of p53, measured by the levels of acetylated α-tubulin and the rate of centrosomal MT nucleation.

Stathmin/oncoprotein 18, a microtubule regulatory protein, is required for survival of both normal and cancer cell lines lacking the tumor suppressor, p53.

Stathmin, a microtubule regulatory protein, is overexpressed in many cancers and required for survival of several cancer lines. In a study of breast cancer cell lines(1) proposed that stathmin is required for survival of cells lacking p53, but this hypothesis was not tested directly. Here we tested their hypothesis by examining cell survival in cells depleted of stathmin, p53 or both proteins.