Vitamin K uptake in hepatocytes and hepatoma cells. Export

@article{citeulike:608377, abstract = {Hepatocellular carcinoma (HCC) or hepatoma cells have impaired ability to perform vitamin K-dependent carboxylation reactions. Vitamin K can also inhibit growth of HCC cells in vitro. Both carboxylation and growth inhibition are vitamin K dose dependent. We used rat hepatocytes, a vitamin K-growth sensitive (MH7777) and a vitamin K-growth resistant (H4IIE) rat hepatoma cell line to examine vitamin K uptake and vitamin K-mediated microsomal carboxylation. We found that vitamin K is taken up by normal rat hepatocytes against a saturable concentration gradient. The relative rates of uptake by rat hepatocytes and the two rat cell lines MH7777 and H4IIE correlated with their sensitivity to vitamin K-mediated cell growth inhibition. Pooled hepatocytes from liver nodules from rats treated with the hepatocarcinogen diethylnitrosamine (DEN) also had a reduced rate of vitamin K uptake. However, using a cell-free system, microsomes from both normal rat hepatocytes and the two rat hepatoma cell lines had a similar ability to support carboxylation mediated by exogenously added vitamin K. The results support the hypothesis that different sensitivity of hepatoma cells to vitamin K may be due to differences in vitamin K uptake and may be unrelated to the actions of vitamin K on carboxylation.}, address = {Division of Hematology, The Children's Hospital of Philadelphia, USA.}, author = {Li, Z. Q. and He, F. Y. and Stehle, C. J. and Wang, Z. and Kar, S. and Finn, F. M. and Carr, B. I.}, citeulike-article-id = {608377}, citeulike-linkout-0 = {http://view.ncbi.nlm.nih.gov/pubmed/12002802}, citeulike-linkout-1 = {http://www.hubmed.org/display.cgi?uids=12002802}, day = {22}, issn = {0024-3205}, journal = {Life Sci}, keywords = {menaquinone, uptake, vitamink}, month = {March}, number = {18}, pages = {2085--2100}, posted-at = {2006-05-01 03:40:34}, priority = {0}, title = {Vitamin K uptake in hepatocytes and hepatoma cells.}, url = {http://view.ncbi.nlm.nih.gov/pubmed/12002802}, volume = {70}, year = {2002} }

TY - JOUR ID - citeulike:608377 L3 - citeulike-article-id:608377 N2 - Hepatocellular carcinoma (HCC) or hepatoma cells have impaired ability to perform vitamin K-dependent carboxylation reactions. Vitamin K can also inhibit growth of HCC cells in vitro. Both carboxylation and growth inhibition are vitamin K dose dependent. We used rat hepatocytes, a vitamin K-growth sensitive (MH7777) and a vitamin K-growth resistant (H4IIE) rat hepatoma cell line to examine vitamin K uptake and vitamin K-mediated microsomal carboxylation. We found that vitamin K is taken up by normal rat hepatocytes against a saturable concentration gradient. The relative rates of uptake by rat hepatocytes and the two rat cell lines MH7777 and H4IIE correlated with their sensitivity to vitamin K-mediated cell growth inhibition. Pooled hepatocytes from liver nodules from rats treated with the hepatocarcinogen diethylnitrosamine (DEN) also had a reduced rate of vitamin K uptake. However, using a cell-free system, microsomes from both normal rat hepatocytes and the two rat hepatoma cell lines had a similar ability to support carboxylation mediated by exogenously added vitamin K. The results support the hypothesis that different sensitivity of hepatoma cells to vitamin K may be due to differences in vitamin K uptake and may be unrelated to the actions of vitamin K on carboxylation. IS - 18 JF - Life Sci SN - 0024-3205 AD - Division of Hematology, The Children's Hospital of Philadelphia, USA. EP - 2100 TI - Vitamin K uptake in hepatocytes and hepatoma cells. VL - 70 SP - 2085 KW - menaquinone KW - uptake KW - vitamink AU - Li, ZQ AU - He, FY AU - Stehle, CJ AU - Wang, Z AU - Kar, S AU - Finn, FM AU - Carr, BI PY - 2002/03/22/ UR - http://view.ncbi.nlm.nih.gov/pubmed/12002802 ER -