Original Article

Cancer Chemotherapy and Pharmacology

, Volume 64, Issue 6, pp 1157-1163

Open Access This content is freely available online to anyone, anywhere at any time.

Antineoplastic activity of idazoxan hydrochloride

  • G. F. EilonAffiliated with
  • , L. WeisenthalAffiliated withWeisenthal Cancer Group
  • , M. StupeckyAffiliated withDepartment of Medicine, University of California at Irvine
  • , G. LanducciAffiliated withDepartment of Medicine, University of California at Irvine
  • , L. M. SlaterAffiliated withDepartment of Medicine, University of California at Irvine Email author 



Idazoxan hydrochloride (IDA) is a 241 molecular weight imidazoline and adrenoreceptor ligand. It binds to mitochondrial membranes and promotes apoptosis of pancreatic beta cells. Since IDA has not been tested against tumor cells, the purpose of our study was to determine if IDA has antineoplastic activity.


We used the conversion of a soluble tetrazolium salt to an insoluble formazan precipitate and differential staining cytotoxicity assays to determine if IDA was cytotoxic to cell lines of murine lung cancer and human prostate cancer, as well as to a variety of fresh human tumor samples. We used flow cytometry to analyze cell death and calreticulin expression.


IDA is cytotoxic to both cell lines and against aliquots of specimens of breast, gastric, lung, ovarian and prostate cancers as well as non-Hodgkin’s lymphoma. It produces apoptotic cell death and promotes calreticulin expression, suggesting that IDA might be immunomodulatory in vivo.


We anticipate that IDA will be clinically useful in cancer treatment.


Idazoxan Imidazoline receptor Calreticulin Apoptosis Human tumors