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Western blot analysis of extracts from Jurkat cells, untreated (-) or treated with PX-866 (1 μM; +) or Wortmannin #9951 (1 μM; +) for the indicated times, using Phospho-Akt (Ser473) (D9E) XP® Rabbit mAb #4060 (upper) and Akt (pan) (C67E7) Rabbit mAb #4691 (lower).

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Product Usage Information

PX-866 is supplied as a lyophilized powder. For a 10mM stock, reconstitute the 1 mg in 190.26 μl DMSO. Working concentrations and length of treatment can vary depending on the desired effect, but it is typically used at 10 nM-1000 nM for 1-24 hours.

Storage: Store lyophilized or in solution at -20ºC, desiccated. In lyophilized form, the chemical is stable for 24 months. Once in solution, use within 3 months to prevent loss of potency. Aliquot to avoid multiple freeze/thaw cycles.

Product Description

Molecular Weight:

525.59 g/mol



Molecular Formula:



Solubility: Soluble in DMSO and ethanol at 200 mg/ml. Very poorly soluble in water.

PX-866 is a potent derivative of wortmannin that irreversibly inhibits PI3 kinase (1). Research studies demonstrate that PX-866 elicits a more sustained inhibition of PI3K than wortmannin. While both chemicals inhibit Akt phosphorylation similarly at short time periods (1-2 hr), PX-866 also demonstrates inhibitory effects for extended time periods (24 hr) at lower doses than wortmannin. This difference may be attributed to wortmannin’s short half-life of 10 minutes and the reduced cytotoxicity of PX-866 (2). PX-866 inhibits the PI3K pathway through down regulation of cyclin D1 protein, which is responsible for regulating cell cycle progression and autophagy induction (3). Additional research shows that PX-866 inhibits cell migration in cancer cell lines (2).

1.  Ihle, N.T. et al. (2004) Mol Cancer Ther 3, 763-72.

2.  Howes, A.L. et al. (2007) Mol Cancer Ther 6, 2505-14.

3.  Koul, D. et al. (2010) Neuro Oncol 12, 559-69.

For Research Use Only. Not For Use In Diagnostic Procedures.
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XP is a registered trademark of Cell Signaling Technology, Inc.