Abstract
It has been reported that estrogen receptor-positive MCF-7 cells express TauT, a Na+-dependent taurine transporter. However, there is a paucity of information relating to the characteristics of taurine transport in this human breast cancer cell line. Therefore, we have examined the characteristics and regulation of taurine uptake by MCF-7 cells. Taurine uptake by MCF-7 cells showed an absolute dependence upon extracellular Na+. Although taurine uptake was reduced in Cl- free medium a significant portion of taurine uptake persisted in the presence of NO3 -. Taurine uptake by MCF-7 cells was inhibited by extracellular β-alanine but not by L-alanine or L-leucine. 17β-estadiol increased taurine uptake by MCF-7 cells: the Vmax of influx was increased without affecting the Km. The effect of 17β-estradiol on taurine uptake by MCF-7 cells was dependent upon the presence of extracellular Na+. In contrast, 17β-estradiol had no significant effect on the kinetic parameters of taurine uptake by estrogen receptor-negative MDA-MB-231 cells. It appears that estrogen regulates taurine uptake by MCF-7 cells via TauT. In addition, Na+-dependent taurine uptake may not be strictly dependent upon extracellular Cl-.
[1] Huxtable, R.J. Physiological actions of taurine. Physiol. Rev. 72 (1992) 101–163. Search in Google Scholar
[2] Lambert, I.H. Regulation of the cellular content of the organic osmolyte taurine in mammalian cells. Neurochem. Res. 29 (2004) 27–63. http://dx.doi.org/10.1023/B:NERE.0000010433.08577.9610.1023/B:NERE.0000010433.08577.96Search in Google Scholar
[3] Uchida S., Kwon H.M., Yamauchi A., Preston A.S., Marumo F. and Handler J.S. Molecular cloning of the cDNA for an MDCK cell Na+-and Cl-dependent taurine transporter that is regulated by hypertonicity. Proc. Natl. Acad. Sci. USA 89 (1992) 8230–8234. http://dx.doi.org/10.1073/pnas.89.17.823010.1073/pnas.89.17.8230Search in Google Scholar
[4] Liu Q., Lopez-Corcuera S., Nelson H., Mandiyan S. and Nelson N. Cloning and expression of a cDNA encoding the transporter of taurine and β-alanine in mouse brain. Proc. Natl. Acad. Sci. USA 89 (1992) 12145–12149. http://dx.doi.org/10.1073/pnas.89.24.1214510.1073/pnas.89.24.12145Search in Google Scholar
[5] Jhiang, S.M., Fithian, L., Smanik, P. McGill, J., Tong, Q. and Mazzaferri E.L. Cloning of the human taurine transporter and characterization of taurine uptake in thyroid cells. FEBS Lett. 318 (1993) 139–144. http://dx.doi.org/10.1016/0014-5793(93)80008-I10.1016/0014-5793(93)80008-ISearch in Google Scholar
[6] Ramamoorthy, S., Leibach, F.H., Mahesh, V.B., Han, H., Yang-Feng T., Blakely, R.D. and Ganapathy V. Functional characterization and chromosomal localization of a cloned taurine transporter from human placenta. Biochem. J. 300 (1994) 893–900. Search in Google Scholar
[7] Vinnakota, S., Qian, X., Egal, H., Sarthy, V. and Sarkar H. Molecular characterization and in situ localization of a mouse retinal taurine transporter. J. Neurochem. 69 (1997) 2238–2250. http://dx.doi.org/10.1046/j.1471-4159.1997.69062238.x10.1046/j.1471-4159.1997.69062238.xSearch in Google Scholar
[8] Lambert, I.H. Taurine transport in Ehrlich ascites tumour cells, Specificity and chloride dependence. Mol. Physiol. 7 (1985) 323–332. Search in Google Scholar
[9] Ballatori, N. and Boyer, N.L. Taurine transport in skate hepatocytes. Am. J. Physiol. 262 (1992) G445–G450. 10.1152/ajpgi.1992.262.3.G445Search in Google Scholar
[10] Shennan, D.B. Identification of a high affinity taurine transporter which is not dependent on chloride. Bioscience Rep. 15 (1995) 231–239. http://dx.doi.org/10.1007/BF0154045710.1007/BF01540457Search in Google Scholar
[11] Bryson, J.M., Jackson, S.C., Wang, H. and Hurley W.L. Cellular uptake of taurine by lactating porcine mammary tissue. Comp. Biochem. Physiol. Part B 128 (2000) 667–673. http://dx.doi.org/10.1016/S1096-4959(00)00361-410.1016/S1096-4959(00)00361-4Search in Google Scholar
[12] Han, X. Patters, A.B. and Chesney R.W. Transactivation of TauT by p53 in MCF-7 cells: the role of estrogen receptors. Adv. Exp. Med. Biol. 526 (2003) 139–147. 10.1007/978-1-4615-0077-3_18Search in Google Scholar PubMed
[13] Pine, M., Kim, U. and Ip C. Free amino acid pools of rodent mammary tumors. J. Natl. Can. Inst. 69 (1982) 729–735. Search in Google Scholar
[14] Beckonert, O., Monnerjahn, J., Bonk, U. and Leibfritz D. Visualizing metabolic changes in breast-cancer tissue using 1H-NMR spectroscopy and self-organizing maps. NMR Biomed. 16 (2003) 1–11. http://dx.doi.org/10.1002/nbm.79710.1002/nbm.797Search in Google Scholar PubMed
[15] Moreno, A., Rey, M., Montane, J.M., Alonso, J. and Arus C. 1H NMR spectroscopy of colon tumours and normal mucosal biopsies; elevated taurine levels and reduced polyethyleneglycol absorption in tumors may have diagnostic significance. NMR Biomed. 6 (1993) 111–118. http://dx.doi.org/10.1002/nbm.194006020210.1002/nbm.1940060202Search in Google Scholar
[16] Palacin, M., Estevez, R., Bertran, J. and Zorzano A. Molecular biology of mammalian plasma membrane amino acid transporters. Physiol. Rev. 78 (1998) 969–1054. Search in Google Scholar
[17] Bhat, H.K. and Vadgama J.V. Role of estrogen receptor in the regulation of estrogen induced amino acid transport of system A in breast cancer and other receptor positive tumor cells. Int. J. Mol. Med. 9 (2002) 271–279. Search in Google Scholar
[18] Shennan, D.B., Thomson, J., Gow, I.F., Travers, M.T. and Barber M.C. L-Leucine transport in human breast cancer cells (MCF-7 and MBA-MB-231): kinetics, regulation by estrogen and molecular identity of the transporter. Biochim. Biophys. Acta 1664 (2004) 206–216. http://dx.doi.org/10.1016/j.bbamem.2004.05.00810.1016/j.bbamem.2004.05.008Search in Google Scholar
[19] Storey, B.T., Fugere, C., Lesieur-Brooks, A., Vaslet, C. and Thompson N.L. Adenoviral modulation of the tumor-associated system L amino acid transporter, LAT1, alters amino acid transport, cell growth and 4F2/CD98 expression with cell-type specific effects in cultured hepatic cells. Int. J. Cancer 117 (2005) 387–397. http://dx.doi.org/10.1002/ijc.2116910.1002/ijc.21169Search in Google Scholar
[20] Haussinger, D. The role of cellular hydration in the regulation of cell function. Biochem. J. 313 (1996) 697–710. Search in Google Scholar
[21] Grant, A.C., Gow, I.F., Zammit, V.A. and Shennan D.B., Regulation of protein synthesis in lactating rat mammary tissue by cell volume. Biochim. Biophys. Acta 1475 (2000) 39–46. Search in Google Scholar
[22] Lang, F., Busch, G.L., Ritter, M., Volkl, H., Waldegger, S., Gulbins, E. and Haussinger D. Functional significance of cell volume regulatory mechanisms. Physiol. Rev. 78 (1998) 247–306. Search in Google Scholar
[23] Shennan, D.B., Thomson, J. and Gow, I.F. Osmoregulation of Taurine efflux from cultured human breast cancer cells: comparison with volume-activated Cl-efflux and regulation by extracellular ATP. Cell. Physiol. Biochem. 18 (2006) 113–122. http://dx.doi.org/10.1159/00009517810.1159/000095178Search in Google Scholar
[24] Tchoumkeu, G.C. and Rebel, G. Characterization of taurine transport in human glioma GL15 cell line: regulation by protein kinase C. Neuropharmacology 35 (1996) 37–44. http://dx.doi.org/10.1016/0028-3908(95)00139-510.1016/0028-3908(95)00139-5Search in Google Scholar
© 2007 University of Wrocław, Poland
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.
