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Collection of Tissue Samples for Study of Multidrug Resistance

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ClinicalTrials.gov Identifier: NCT00880503
Recruitment Status : Completed
First Posted : April 13, 2009
Last Update Posted : February 12, 2018
Information provided by (Responsible Party):
National Institutes of Health Clinical Center (CC) ( National Cancer Institute (NCI) )

Brief Summary:


Resistance to cancer chemotherapy develops in patients, rendering certain treatments ineffective. Despite much research, the prevailing cause of drug resistance is not known.

One mechanism for drug resistance involves a protein called P-glycoprotein, or Pgp, which reduces the effectiveness of cancer treatments by "pumping" anti-cancer drugs out of tumor cells where they are supposed to work against the disease.


To identify and evaluate more thoroughly the roles of Pgp and other substances in mediating drug resistance.


Patients enrolled in clinical trials of cancer therapies at the Children's Hospital of Pittsburgh; Cancer Centers of Carolinas; Arizona Clinical Research Center; University of Copenhagen; and Herlev Hospital, Copenhagen who have consented to the use of blood, tissue, or tumor samples for laboratory studies.


Blood, tumor, and tissue samples are collected from participants and sent to the NCI for various laboratory analyses.

Condition or disease
Breast Carcinoma Breast Cancer Medullary Thyroid Carcinoma

Detailed Description:


Ultimately, patients who succumb to cancer do so because of drug resistance. Mechanisms of drug resistance have been explored in the laboratory and in clinical samples for some time, yet the prevailing cause of drug resistance, if indeed there is a single cause, is not known. One mechanism of drug resistance is multidrug efflux, mediated by P-glycoprotein. Other mechanisms have been proposed. Our laboratory has expertise in the analysis of drug transporter expression and activity in clinical samples.


To determine expression of P-glycoprotein and other multidrug transporters thought to mediate clinical drug resistance.

To evaluate inhibition of P-glycoprotein and other multidrug transporters through assessment of efflux activity in cells obtained from patients enrolled on clinical trials at other institutions.

To identify and evaluate mechanisms of drug resistance using molecular assays such as cDNA array, real-time PCR analysis, and immunohistochemistry.


Patients enrolled on clinical trials outside the NCI, and giving informed consent to the use of blood, tissue, or tumor samples for evaluation of mechanisms of drug resistance or evaluation of inhibition of multi-drug efflux.

Future collaborations for similar studies will be added via the protocol amendment procedure; molecular studies other than ABC transporter assays will be added via the protocol amendment procedure.


Human tumor biopsies or blood samples will be collected from cancer patients enrolled on approved clinical trials, in accordance with the local protocol. These trials are being conducted at outside institutions, and the samples will be sent to the NCI for immunohistochemical analysis, cDNA array, PCR analysis, or for blood assays for detection of P-glycoprotein inhibition.

Study Type : Observational
Estimated Enrollment : 9999 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Multidrug Resistance Molecular Target Analysis of Human Samples Collected in Clinical Trials Performed Outside of the Intramural National Cancer Institute
Study Start Date : December 19, 2003
Estimated Study Completion Date : February 8, 2018

Primary Outcome Measures :
  1. Expression of MDR1/P-glycoprotein and related drug resistance proteins [ Time Frame: Upon receipt and processing of specimen ]

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 99 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Any patients entered on approved trials of cancer therapeutics at Children's Hospital of Pittsburgh, Herlev Hospital, and the University of Copenhagen outside of the intramural NCI are eligible for inclusion, provided that they have consented to tumor studies in the original consent forms.


None anticipated at this time.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00880503

United States, Pennsylvania
Childrens Hospital, Pittsburgh
Pittsburgh, Pennsylvania, United States, 15213-2583
Sponsors and Collaborators
National Cancer Institute (NCI)
Principal Investigator: William D Figg, Pharm.D. National Cancer Institute (NCI)

Responsible Party: National Cancer Institute (NCI)
ClinicalTrials.gov Identifier: NCT00880503     History of Changes
Obsolete Identifiers: NCT00898001
Other Study ID Numbers: 999904067
First Posted: April 13, 2009    Key Record Dates
Last Update Posted: February 12, 2018
Last Verified: February 8, 2018

Keywords provided by National Institutes of Health Clinical Center (CC) ( National Cancer Institute (NCI) ):
Multidrug Resistance Molecular Target Analysis

Additional relevant MeSH terms:
Breast Neoplasms
Thyroid Neoplasms
Carcinoma, Neuroendocrine
Neoplasms, Glandular and Epithelial
Neoplasms by Histologic Type
Neoplasms by Site
Breast Diseases
Skin Diseases
Endocrine Gland Neoplasms
Head and Neck Neoplasms
Endocrine System Diseases
Thyroid Diseases
Neuroendocrine Tumors
Neuroectodermal Tumors
Neoplasms, Germ Cell and Embryonal
Neoplasms, Nerve Tissue