Objectives: The role of MDR1 in clinical paclitaxel resistance remains poorly characterized. This study sought to identify the incidence and significance of P-glycoprotein (P-gp) over-expression on survival, tumor response to paclitaxel and the effect of prior cytotoxic exposure on P-gp expression in patients with paired primary and recurrent ovarian cancer samples.
Methods: Retrospective survival analysis. P-gp expression was evaluated immunohistochemically with antibodies c494 and c219.
Results: Thirty-two patients were identified from the tumor registry. Median interval between primary and secondary surgery was 17.9 (5.7-40.9) months. Only five primary tumors (16%) demonstrated +++ staining for P-gp. First-line treatment contained paclitaxel in 17 patients (53%) and 26 patients (81%) had been exposed to P-gp exportable chemotherapy before second surgery. Only seven of the recurrent tumors (22%) were +++. Only one of seven (14% (95% CI 0-46%)) recurrent tumors with ++ or +++ staining responded to subsequent paclitaxel, while 8 of 10 (80% (CI 46-100%)) recurrent tumors with 0/+ staining responded (P = 0.025). In multivariate analysis of outcome following second surgery, response to paclitaxel (P = 0.004) and P-gp over-expression (P < 0.001) were significant predictors of survival.
Conclusions: De novo strong P-gp over-expression is uncommon, appears to change little over time or with prior exposure to chemotherapy. However, P-gp over-expression is a significant prognostic factor, and at the time of disease, relapse is inversely correlated with tumor response to paclitaxel.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.ygyno.2003.11.053 | DOI Listing |
Anticancer Res
December 2024
Department of Pulmonary Medicine and Oncology, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
Background/aim: Chemoresistance to paclitaxel (PTX) significantly ameliorates therapeutic efficacy in patients with non-small cell lung cancer (NSCLC), especially in advanced stages, deteriorating the progression free and overall survival rates. One of the critical mechanisms contributing to drug resistance is the excretion of PTX from target cells via efflux pumps. Ivermectin was developed as a bactericidal agent against parasites; however, it has recently been shown to inhibit the proliferation of human cancer cells.
View Article and Find Full Text PDFEur J Med Chem
January 2025
School of Pharmacy, Fudan University, Shanghai, 201203, China. Electronic address:
Basic Clin Neurosci
September 2023
Department of Neurosurgery, Institute of Medical Education and Research, Chandigarh, India.
Expert Rev Hematol
February 2024
Department of Hematology, The Affiliated People's Hospital of Ningbo University, Ningbo, Zhejiang, China.
Background: This study aimed to explore the effect and mechanism of SCN5A overcoming ATP-binding cassette (ABC) transporter-mediated multidrug resistance (MDR) in acute myeloid leukemia (AML) through promoting apoptosis.
Research Design And Methods: The tissues derived from AML patients were divided into Sensitive group and Resistance group according to the presence of drug-resistance. Human AML cell line HL-60 and drug-resistant strain HL-60/ADR were divided into HL-60/ADR-vector group, HL-60/ADR-SCN5A group, HL-60-vector group and HL-60-SCN5A group.
Bioorg Chem
February 2024
University College of Pharmacy Raipur, Chhattisgarh Swami Vivekananda Technical University, Newai, Bhilai 491107, Chhattisgarh, India. Electronic address:
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!