Artificial DnaJ Protein for protein production and conformational diseases.

For secreted proteins, proper protein folding is essential not only for biological function but also for secretion itself. Proteins with folding problems are trapped in the endoplasmic reticulum (ER) and are eventually degraded in the cytoplasm. In this study, we exploited co-expression of an artificial fusion protein, based on the sequence of a DnaJ protein, which could interact as co-chaperones in the Hsp70-based protein-folding system, with target recombinant secreted proteins to enhance their production and secretion.

Synthesis, crystallographic characterization and electrochemical property of a copper(II) complex of the anticancer agent elesclomol.

Elesclomol is a novel anticancer agent that has been evaluated in a number of late stage clinical trials. A new and convenient synthesis of elesclomol and its copper complex is described. X-ray crystallographic characterization and the electrochemical properties of the elesclomol copper(II) complex are discussed.

A rat retinal damage model predicts for potential clinical visual disturbances induced by Hsp90 inhibitors.

In human trials certain heat shock protein 90 (Hsp90) inhibitors, including 17-DMAG and NVP-AUY922, have caused visual disorders indicative of retinal dysfunction; others such as 17-AAG and ganetespib have not. To understand these safety profile differences we evaluated histopathological changes and exposure profiles of four Hsp90 inhibitors, with or without clinical reports of adverse ocular effects, using a rat retinal model. Retinal morphology, Hsp70 expression (a surrogate marker of Hsp90 inhibition), apoptotic induction and pharmacokinetic drug exposure analysis were examined in rats treated with the ansamycins 17-DMAG and 17-AAG, or with the second-generation compounds NVP-AUY922 and ganetespib.

Syntheses and antitumor activities of N'1,N'3-dialkyl-N'1,N'3-di-(alkylcarbonothioyl) malonohydrazide: the discovery of elesclomol.

A series of N'(1),N'(3)-dialkyl-N'(1),N'(3)-di(alkylcarbonothioyl) malonohydrazides have been designed and synthesized as anticancer agents by targeting oxidative stress and Hsp70 induction. Structure-activity relationship (SAR) studies lead to the discovery of STA-4783 (elesclomol), a novel small molecule that has been evaluated in a number of clinical trials as an anticancer agent in combination with Taxol.

The oncology drug elesclomol selectively transports copper to the mitochondria to induce oxidative stress in cancer cells.

Elesclomol is an investigational drug that exerts potent anticancer activity through the elevation of reactive oxygen species (ROS) levels and is currently under clinical evaluation as a novel anticancer therapeutic. Here we report the first description of selective mitochondrial ROS induction by elesclomol in cancer cells based on the unique physicochemical properties of the compound. Elesclomol preferentially chelates copper (Cu) outside of cells and enters as elesclomol-Cu(II).

Synergistic activity of the Hsp90 inhibitor ganetespib with taxanes in non-small cell lung cancer models.

Systemic chemotherapy using two-drug platinum-based regimens for the treatment of advanced stage non-small cell lung cancer (NSCLC) has largely reached a plateau of effectiveness. Accordingly, efforts to improve survival and quality of life outcomes have more recently focused on the use of molecularly targeted agents, either alone or in combination with standard of care therapies such as taxanes. The molecular chaperone heat shock protein 90 (Hsp90) represents an attractive candidate for therapeutic intervention, as its inhibition results in the simultaneous blockade of multiple oncogenic signaling cascades.

Ganetespib, a unique triazolone-containing Hsp90 inhibitor, exhibits potent antitumor activity and a superior safety profile for cancer therapy.

Targeted inhibition of the molecular chaperone Hsp90 results in the simultaneous blockade of multiple oncogenic signaling pathways and has, thus, emerged as an attractive strategy for the development of novel cancer therapeutics. Ganetespib (formerly known as STA-9090) is a unique resorcinolic triazolone inhibitor of Hsp90 that is currently in clinical trials for a number of human cancers. In the present study, we showed that ganetespib exhibits potent in vitro cytotoxicity in a range of solid and hematologic tumor cell lines, including those that express mutated kinases that confer resistance to small-molecule tyrosine kinase inhibitors.

Mortalin inhibition in experimental Parkinson's disease.

Among heat shock proteins, mortalin has been linked to the pathogenesis of Parkinson's disease. In the present work a rat model of Parkinson's disease was used to analyze the expression of striatal proteins and, more specifically, mortalin expression. The possible involvement of mortalin in Parkinson's disease pathogenesis was further investigated by utilizing an electrophysiological approach and pharmacological inhibition of mortalin in both the physiological and the parkinsonian states.

Multifaceted intervention by the Hsp90 inhibitor ganetespib (STA-9090) in cancer cells with activated JAK/STAT signaling.

There is accumulating evidence that dysregulated JAK signaling occurs in a wide variety of cancer types. In particular, mutations in JAK2 can result in the constitutive activation of STAT transcription factors and lead to oncogenic growth. JAK kinases are established Hsp90 client proteins and here we show that the novel small molecule Hsp90 inhibitor ganetespib (formerly STA-9090) exhibits potent in vitro and in vivo activity in a range of solid and hematological tumor cells that are dependent on JAK2 activity for growth and survival.

Mortalin inhibitors sensitize K562 leukemia cells to complement-dependent cytotoxicity.

Mortalin, the mitochondrial hsp70, is a vital constitutively expressed heat shock protein. Its elevated expression has been correlated with malignant transformation and poor cancer prognosis. Cancer cells exhibit increased resistance to complement-dependent cytotoxicity, partly due to their capacity to eliminate the complement membrane attack complex (MAC) from their cell surface.

Indole- and indolizine-glyoxylamides displaying cytotoxicity against multidrug resistant cancer cell lines.

We report herein the SAR studies of a series of indole- and indolizine-glyoxylamides that demonstrate substantial in vitro anti-proliferative activities against cancer cell lines, including multidrug resistance (MDR) phenotypes. The in vitro cytotoxic effects have been demonstrated across a wide array of tumor types of various origins (e.g.

Conjugated indole-imidazole derivatives displaying cytotoxicity against multidrug resistant cancer cell lines.

We report herein the SAR studies of a series of indole-imidazole compounds. that demonstrate substantial in vitro anti-proliferative activities against cancer cell lines, including multidrug resistance (MDR) phenotypes. The in vitro cytotoxic effects have been demonstrated across a wide array of tumor types, including hematologic and solid tumor cell lines of various origins (e.