Abstract
It has been suggested that exogenous unsaturated fatty acids (UFAs) may increase the cytotoxic activity of cancer chemotherapeutic agents. We examined how γ-linolenic acid (GLA; 18 : 3n-6), the most promising UFA in the treatment of human tumors, affects the effectiveness of the lipophilic drug vinorelbine (VNR) on human breast carcinoma cell lines. Cells were exposed simultaneously to VNR and GLA or sequentially to GLA followed by VNR. Cell viability was determined by MTT assay. The increase in VNR-induced cell growth inhibition was measured by dividing the IC50 and IC70 values (50 and 70% inhibitory concentrations, respectively) that were obtained when the cells were exposed to VNR alone with those with VNR plus GLA. We found that GLA enhanced in a dose-dependent manner the cell growth inhibitory activity of VNR on MCF-7 cells (up to 9-fold). As GLA by itself showed anti-proliferative effects, possible GLA-VNR interactions at the cellular level were assessed employing the isobologram analysis and the combination index (CI) method of Chou–Talalay. Both methods showed an overall synergism between GLA and VNR in MCF-7 cells. At a high level of cell kill, the synergism was greater when a 24 h GLA pre-exposure or co-exposures were tested. Synergy was likewise observed with the GLA-VNR combination in MDA-MB-231, T47D, and SK-Br3 breast cancer cells. In all cell lines, the synergism was independent of the treatment schedule and the exposure time. Under conditions inhibiting lipid peroxidation using Vitamin E (dl-α-tocopherol), the enhancing effect of GLA (an easily oxidizable UFA) on VNR activity was partially abolished. However, when Vitamin E was used in combination, a similar synergistic increase in growth inhibition was obtained. These latter observations strongly implies that the synergistic effects of GLA with VNR are not mediated through a mechanism involving a generation of lipoperoxides. For comparison, the effects of other UFAs were examined on VNR chemosensitivity: GLA was the most potent at enhancing VNR activity, followed by docosahexaenoic acid (22 : 6n-3), eicosapentaenoic acid (20 : 5n-3) and α-linolenic acid (18 : 3n-3), whereas linoleic acid (18 : 2n-6) and arachidonic acid (20 : 4n-6) did not increase VNR chemosensitivity. Very high concentrations of oleic acid (OA; 18 : 1n-9), an UFA inversely correlated with breast cancer risk, also enhanced VNR effectiveness. Thus, various types of UFAs were not equivalent with respect to their actions on VNR effectiveness. In conclusion, our results give experimental support to the hypothesis that some UFAs can be used as modulators of tumor cell chemosensitivity and provide the rationale for in vivo preclinical investigation.
Similar content being viewed by others
References
Solanas M, Moral R, Colomer R, Escrich E: Effects of dietary (n-6) polyunsaturated lipids on experimental mammary carcinogenesis. J Women's Cancer 2: 67–72, 2000
Welsch C.W: Relationship between dietary fat and experimental mammary tumorigenesis: a review and critique. Cancer Res. 52: 2040s–2048s, 1992
Rose D.P: Effects of dietary fatty acids on breast and prostate cancers: evidence from in vitro experiments and animal studies. Am J Clin Nutr 66: 1513S–1522S, 1997
Bégin ME, Ells G, Das UN, Horrobin DF: Differential killing of human carcinoma cells supplemented with n-3 and n-6 polyunsaturated fatty acids. J Natl Cancer Inst 77: 1053–1062, 1986
Bégin ME, Das UN, Ells G: Cytotoxic effects of essential fatty acids in mixed cultures of normal and malignant human cells. Prog Lipid Res 25: 573–576, 1986
Hawkins RA, Sangster K, Arends MJ: Apoptotic death of pancreatic cancer cells induced by polyunsaturated fatty acids varies with double bond number and involves an oxidative mechanism. J Pathol 185: 61–70, 1998
Vartak S, McCaw R, Davis CS, Robbins ME, Spector AA: Gamma-linolenic acid (GLA) is cytotoxic to 36B10 malignant rat astrocytoma cells but not to “normal” rat astrocytes. Br J Cancer 77: 1612–1620, 1998
Jiang WG, Bryce RP, Horrobin DF: Essential fatty acids: molecular and cellular basis of their anti-cancer action and clinical implications. Crit Rev Oncol Hematol 27: 179–209, 1998
Germain E, Chajès V, Cognault S, Lhuillery C, Bougnoux P: Enhancement of doxorubicin cytotoxicity by polyunsaturated fatty acids in the human breast tumor cell line MDAMB-231, relationship to lipid peroxidation. Int J Cancer 75: 578–583, 1998
Burns CP, Spector AA: Biochemical effects of lipids in cancer therapy. J Nutr Biochem 5: 114–123, 1994
Borgeson CE, Pardini L, Pardini RS, and Reitz R: Effects of dietary fish oil on human mammary carcinoma and on lipid-metabolizing enzymes. Lipids 24: 290–295, 1989
Shao Y, Pardini L, Pardini RS: Dietary menhanden oil enhances mitomycin C antitumor activity toward human mammary carcinoma MX-1. Lipids 30: 1035–1045, 1995
Shao Y, Pardini L, Pardini RS: Intervention of transplantable human mammary carcinoma MX-1 chemotherapy with dietary menhaden oil in athymic mice: increased therapeutic effects and decreased cytotoxicity of cyclophosphamide. Nutr Cancer 28: 63–73, 1997
Bougnoux P, Germai E, Chàjes V, Hubert B, Lhuillery C, Le Floche O, Body G, Calais G: Cytotoxic drugs efficacy correlates with adipose tissue docohexaenoic acid level in locally advanced breast carcinoma. Br J Cancer 79: 1765–1769, 1999
Bruno S, Puerto VL, Mickiewicz E, Hegg R, Texeira LC, Gaitan L, Martinez L, Fernandez O, Otero J, Kesselring G, Noguera C, Delgado G, Gaubert P, Delgado FM, Solidoro A: Phase II trial of weekly IV vinorelbine as a single agent in first-line advanced breast cancer chemotherapy. Am J Clin Oncol 18: 392–396, 1995
Livingston RB, Ellis GK, Gralow JR, Williams MA, White R, McGuirt C, Adamkiewicz BB, Long CA: Dose-intensive vinorelbine with concurrent granulocyte colony-stimulating factor support in paclitaxel-refractory metastatic breast cancer. J Clin Oncol 15: 1395–1400, 1997
Adams DJ, Knick VC: P-glycoprotein mediated resistance to 5-nor-andhydro-vinblastine (Navelbine_) Invest New Drugs 13: 13–21, 1995
Dumontet C: Mechanisms of action and resistance to tubulin-binding agents. Expert Opin Investig Drugs 9: 779–788, 2000
Horrobin DF: Unsaturated lipids and cancer. In: Horrobin DF (ed) New Approaches to Cancer Treatment. Edinburgh: Churchill Communications, 1994, pp 3–29
De Bravo MG, Schinella G, Tournier H, Quintans C: Effects of dietary gamma and alpha linolenic acid on a human lung carcinoma growth in nude mice. Med Sci Res 22: 667–668, 1994
Pritchard GA, Jones DL, Mansel RE: Lipids in breast carcinogenesis. Br J Surg 76: 1069–1073, 1989
Van Der Merwe CF, Booyens J, Kateef IE: Oral gammalinolenic acid in 21 patients with untreatable malignancy. An ongoing pilot open clinical trial. Br J Clin Prac 41: 907–915, 1987
Fearon KCH, Falconer JS, Ross JA, Carter DC, Hunter JO, Reynolds PD, Tuffnell, Q: An open-label phase I/II dose escalation study of the treatment of pancreatic cancer using lithium gammalinolenate. Anticancer Res 16: 867–874, 1996
Kenny FS, Pinder SE, Ellis IO, Gee JMW, Nicholson RI, Bryce RP, Robertson JFR: Gamma linolenic acid with tamoxifen as primary therapy in breast cancer. Int J Cancer 85: 643–648, 2000
Menéndez JA, Barbacid MM, Montero S, Sevilla E, Escrich E, Solanas M, Cortés-Funes H, Colomer R: Effects of gamma-linolenic acid and oleic acid on paclitaxel cytotoxicity in human breast cancer cells. Eur J Cancer 37: 402–413, 2001
Berenbaum MC: What is synergy? Pharmacol Rev 41: 93–141, 1989
Chou T-C, Talalay, P: Quantitative analysis of dose-effect relationships: the combined effects of multiple drugs or enzyme inhibitors. Adv Enzyme Regul 22: 27–55, 1984
Bégin ME, Ells G, Horrobin DF 1988 Polyunsaturated fatty acid-induced cytotoxicity against tumor cells and its relationship to lipid peroxidation. J Natl Cancer Inst 80: 188–194, 1988
Ford JM, Hait WN: Pharmacology of drugs that alter multidrug resistance in cancer. Pharmacol Rev 42: 155–199, 1990
Burns CP, Haugstad BN, Mossman CJ, North JA, Ingraham LM: Membrane lipid alteration: effect on cellular uptake of mitoxantrone. Lipids 23: 393–397, 1988
Zhou XJ, Rahmani R: Preclinical and clinical pharmacology of vinca alkaloids. Drugs 44 S4: 1–16, 2000
Davies CL, Loizidou M, Cooper AJ, Taylor I: Effect of γ-linolenic acid on cellular uptake of structurally related anthracyclines in human drug sensitive and multidrug resistant bladder and breast cancer cell lines. Eur J Cancer 35: 1534–1540, 1999
Chajes V, Mahon M, Kostner GM: Influence of LDL oxidation on the proliferation of human breast cancer cells. Free Radic Biol Med 20: 113–120, 1996
Hawkins RA, Sangster K, Arends MJ: The apoptosisinducing effects of polyunsaturated fatty acids (PUFAs) on benign and malignant breast cells in vitro. The Breast 8: 16–20, 1999
Wang LG, Liu XM, Kreis W, Budman DR: The effect of antimicrotubule agents on signal transduction pathways of apoptosis: a review. Cancer Chemother Pharmacol 44: 355–361, 1999
Sugiyama K, Shimizu M, Akiyama T, Ishida H, Okabe M, Tamaoki T, Akinaga S: Combined effect of navelbine with medroxyprogesterone acetate against human breast carcinoma MCF-7 cells in vitro. Br J Cancer 77: 1737–1743, 1998
Das UN: Essential fatty acids, lipid peroxidation and apoptosis. Prostaglandins Leukot Essent Fatty Acids 61: 157–163, 1999
Cunnane SC, Chen ZY, Yang J, Liede AC, Hamadeh M, Crawford MA: Alpha-linolenic acid in humans: direct functional role or dietary precursor? Nutrition 7: 437–439, 1991
Sandstrom PA, Pardi D, Tebbey PW, Dudek R, Terrian D, Folks T, Buttke T: Lipid hydroperoxide-induced apoptosis: lack of inhibition by Bcl-2 overexpression. FEBS Lett 365: 66–70, 1995
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Menéendez, J.A., Ropero, S., Barbacid, M.d.M. et al. Synergistic Interaction Between Vinorelbine and Gamma-Linolenic Acid in Breast Cancer Cells. Breast Cancer Res Treat 72, 203–219 (2002). https://doi.org/10.1023/A:1014968415759
Issue Date:
DOI: https://doi.org/10.1023/A:1014968415759