Singer S, Souza K, Thilly W G
Department of Surgery, Brigham and Woman's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
Cancer Res. 1995 Nov 15;55(22):5140-5.
We have used 31P- and 13C-nuclear magnetic resonance spectroscopy to measure key metabolite levels and fluxes through enzymes regulating phospholipid and mitochondrial metabolism in normal human mammary epithelial cells. We have compared these values to those found in a progression series of breast cancer cell lines of varying metastatic potential established from a single patient. We find a 16-19-fold increase in phosphocholine content in two primary breast cancer cell lines (21PT and 21NT) and a 27-fold increase in phosphocholine content in the metastatic breast cancer cell line (21MT-2) compared with the normal breast epithelial cell strain 76N. Thus, phosphocholine may serve as a metabolic marker for the human breast cell progression state. A 30% decrease in ATP levels, a 83% decrease in phosphocreatine levels, along with a 2-fold increase in NAD(+) + NADH levels in 21PT, 21NT, and 21MT-2 cells compared to the normal breast cells further suggests impaired mitochondrial metabolism in the breast carcinoma cell lines. Consistent with this suggestion is our finding that the primary breast cancer cell lines (21PT and 21NT) and the metastatic breast cell line (21MT-2) showed a 50 and 89% relative reduction, respectively, in the flux of pyruvate utilized for mitochondrial energy generation compared to pyruvate utilized to replenish tricarboxylic acid cycle intermediates. These results demonstrate that diminished mitochondrial energy generation may be quantitatively related to the progression state of human breast cells.
我们利用31P和13C核磁共振波谱法来测量正常人乳腺上皮细胞中关键代谢物的水平以及通过调节磷脂和线粒体代谢的酶的通量。我们将这些值与从一名患者建立的具有不同转移潜能的一系列乳腺癌细胞系中的值进行了比较。我们发现，与正常乳腺上皮细胞系76N相比，两个原发性乳腺癌细胞系（21PT和21NT）中的磷酸胆碱含量增加了16至19倍，转移性乳腺癌细胞系（21MT - 2）中的磷酸胆碱含量增加了27倍。因此，磷酸胆碱可能作为人类乳腺细胞进展状态的代谢标志物。与正常乳腺细胞相比，21PT、21NT和21MT - 2细胞中的ATP水平降低了30%，磷酸肌酸水平降低了83%，同时NAD(+) + NADH水平增加了2倍，这进一步表明乳腺癌细胞系中的线粒体代谢受损。与这一推测一致的是，我们发现原发性乳腺癌细胞系（21PT和21NT）和转移性乳腺癌细胞系（21MT - 2）与用于补充三羧酸循环中间体的丙酮酸相比，用于线粒体能量生成的丙酮酸通量分别相对降低了50%和89%。这些结果表明，线粒体能量生成的减少可能与人类乳腺细胞的进展状态在数量上相关。
