de la Fuente M, Hernanz A
Department of Animal Biology II, Faculty of Biological Sciences, Complutense University, Madrid, Spain.
Br J Cancer. 1988 Nov;58(5):567-9. doi: 10.1038/bjc.1988.260.
Mannose in animal cells is phosphorylated by hexokinase (HK) and later isomerised by mannose phosphate isomerase (MPI) to fructose-6-P, which is incorporated in the glycolysis pathway. In this paper we report a significant decrease of MPI activity in splenic lymphoid cells from AKR/J old mice with lymphocytic leukaemia in comparison to that found in splenic lymphocytes from AKR/J non-leukaemic young mice and BALB/c young and old control mice. However, HK with mannose as substrate presents a normal activity in AKR/J leukaemic mice. This marked shortage of MPI explains the in vitro mannose toxicity found by us here in splenic lymphoid cells from AKR/J leukaemic mice. MPI activity was also decreased in peripheral blood lymphocytes from 4 out of the 6 patients studied with chronic lymphocytic leukaemia in relation to the activity found in the lymphocytes from healthy donors. The utility of analysing MPI activity in leukaemia patients and the use of mannose as an innocuous chemotherapic supporting agent in patients with decreased MPI activity is proposed.
动物细胞中的甘露糖被己糖激酶（HK）磷酸化，随后被磷酸甘露糖异构酶（MPI）异构化为6-磷酸果糖，后者进入糖酵解途径。在本文中，我们报告称，与AKR/J非白血病幼鼠以及BALB/c幼龄和老龄对照小鼠的脾淋巴细胞相比，患有淋巴细胞白血病的AKR/J老龄小鼠脾淋巴细胞中的MPI活性显著降低。然而，以甘露糖为底物时，HK在AKR/J白血病小鼠中活性正常。MPI的这种显著缺乏解释了我们在此处发现的AKR/J白血病小鼠脾淋巴细胞的体外甘露糖毒性。在所研究的6例慢性淋巴细胞白血病患者中，有4例患者外周血淋巴细胞中的MPI活性相对于健康供体淋巴细胞中的活性也有所降低。本文提出了分析白血病患者MPI活性的实用性，以及在MPI活性降低的患者中使用甘露糖作为一种无害化疗辅助剂的建议。
