Doxorubicin and its analogs are important anthracycline antibiotics used in cancer chemotherapy. Tumor cell resistance to doxorubicin is often related to reduced influx and/or enhanced efflux. We have used laser flow cytometry and clonogenic assays to study anthracycline transport, retention and cytotoxicity in murine leukemic cells. We have developed methods for rapid identification and laser activated sorting of drug resistant cells on the basis of their drug retention and presence of resistance felated markers. our preliminary studies on human solid tumors show that unlike murine in vitro cell lines, cells from these tumors express extreme heterogeneity in drug ratention and sensitivity to drugs which block drug efflux and enhance retention and cytotoxicity. In this revised competitive renewal, we propose to extend our multifaceted studies on murine cells to selected human melanoma cell lines and their xenografts. These tumor lines cover a wide range of doxorubicin sensitivity from very low to very high resistance. We propose to use our rapid methods to correlate drug retention, sensitivity to drug efflux blockers (phenothiazines), presence or absence of various biochemical and biophysical markers of resistance with effects on clonogenecity and xenograft growth inhibition. We will carry out specific studies to delineate the role of drug transport, DNA damage/repair, and scavenging of free radicals in tesistance of human melanomas to anthracyclines. It is hoped that use of our rapid analytical methods will allow us to better understand anthracycline effects on proliferation, correlation between drug retention, presence or absence of resistance related markers, and cellular resistance of human melanoma cells to this important class of chemotherapeutic agents.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
2R01CA029360-07A2
Application #
3168680
Study Section
Experimental Therapeutics Subcommittee 2 (ET)
Project Start
1980-12-01
Project End
1994-04-30
Budget Start
1989-07-01
Budget End
1990-04-30
Support Year
7
Fiscal Year
1989
Total Cost
Indirect Cost
Name
University of Miami School of Medicine
Department
Type
Schools of Medicine
DUNS #
City
Miami
State
FL
Country
United States
Zip Code
33101
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Ramachandran, C; You, W; Krishan, A (1997) Bcl-2 and mdr-1 gene expression during doxorubicin-induced apoptosis in murine leukemic P388 and P388/R84 cells. Anticancer Res 17:3369-76
Mou, C; Ganju, N; Sridhar, K S et al. (1997) Simultaneous quantitation of plasma doxorubicin and prochlorperazine content by high-performance liquid chromatography. J Chromatogr B Biomed Sci Appl 703:217-24
Krishan, A; Fitz, C M; Andritsch, I (1997) Drug retention, efflux, and resistance in tumor cells. Cytometry 29:279-85
Kunikane, H; Zalupski, M M; Ramachandran, C et al. (1997) Flow cytometric analysis of P-glycoprotein expression and drug efflux in human soft tissue and bone sarcomas. Cytometry 30:197-203
Isobe, H; Sridhar, K S; Doria, R et al. (1995) Prognostic significance of DNA aneuploidy in diffuse malignant mesothelioma. Cytometry 19:86-91
Ramachandran, C; Mead, D; Wellham, L L et al. (1995) Expression of drug resistance-associated mdr-1, GST pi, and topoisomerase II genes during cell cycle traverse. Biochem Pharmacol 49:545-52
Isobe, H; Wellham, L; Sauerteig, A et al. (1994) Doxorubicin retention and chemoresistance in human mesothelioma cell lines. Int J Cancer 57:581-5
Sridhar, K S; Krishan, A; Samy, T S et al. (1994) Phase I and pharmacokinetics studies of prochlorperazine 2-h i.v. infusion as a doxorubicin-efflux blocker. Cancer Chemother Pharmacol 34:377-84
Ramachandran, C; Samy, T S; Huang, X L et al. (1993) Doxorubicin-induced DNA breaks, topoisomerase II activity and gene expression in human melanoma cells. Biochem Pharmacol 45:1367-71

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