P-glycoprotein expression and multidrug resistance in adrenocortical carcinoma

S. D. Flynn, J. R. Murren, W. M. Kirby, J. Honig, L. Kan, B. K. Kinder

Research output: Contribution to journalArticlepeer-review

50 Scopus citations


Background. The response of adrenocortieal carcinoma (ACC) to adjuvant chemotherapy has been disappointing with no significant impact on survival. The normal adrenal cortex has very high levels of P-glycoprotein, an energy-dependent efflux pump of a variety of structurally unrelated chemotherapeutic agents. P-glycoprotein has been implicated as a cause of multidrug resistance in a variety of neoplasms. The purpose of this study was to evaluate P-glycoprotein expression in ACC. Methods. Eleven patients with ACC had paraffin-em bedded tumor evaluated for P-glycoprotein expression. These were analyzed by immunohistochemistry assay with a battery of four anti-P-glycoprotein antibodies (MRK-16, JSB-1, UIC-2, MDR). Results. All eleven cases showed intense, predominantly membrane immunoreactivity for P-glycoprotein. In 10 of the cases, most tumor cells were immunoreactive with at least three antibodies, and six of 11 cases were positive for all four antibodies. In this small series no correlation existed between P-glycoprotein expression and tumor grade, stage of disease, or survival. Conclusions. All 11 cases of ACC studied showed P-glycoprotein expression, which was similar to the normal adrenal cortex. This possible mechanism of multidrug resistance may help explain the significant chemoresistance seen in ACC.

Original languageEnglish (US)
Pages (from-to)981-986
Number of pages6
Issue number6
StatePublished - Dec 1992
Externally publishedYes

ASJC Scopus subject areas

  • Surgery


Dive into the research topics of 'P-glycoprotein expression and multidrug resistance in adrenocortical carcinoma'. Together they form a unique fingerprint.

Cite this