Elitsur Y, Moshier J A, Murthy R, Barbish A, Luk G D
Department of Medicine, Harper-Grace Hospitals, Detroit, Michigan.
Life Sci. 1992;50(19):1417-24. doi: 10.1016/0024-3205(92)90260-v.
Ornithine decarboxylase (ODC) and polyamines (putrescine, spermidine, and spermine) are crucial for cell proliferation. Recently, elevated ODC activity and polyamine levels have been suggested as biological markers for human colon cancer. In this study, we measured ODC activity and the levels of polyamines (putrescine, spermidine, spermine, and cadaverine) and acetyl-putrescine in human colonocytes isolated from cancerous areas compared to the adjacent normal colon tissue. In addition, ODC mRNA expression was compared between both groups. We found that colonocytes isolated from cancerous areas had significantly higher mean value of ODC activity, putrescine, spermidine, spermine, and cadaverine levels up to 1480%, 470%, 260%, 380%, and 510% respectively compared to colonocytes isolated from the adjacent normal colonic mucosa. No difference was found in acetyl-putrescine levels between cancerous and normal colonocytes. Steady-state levels of ODC mRNA were slightly elevated in cancerous colonocytes relative to normal colonocytes in two of three paired samples. However, the increase in ODC mRNA levels is not sufficient to account for the increase in ODC activity suggesting that colonocyte ODC activity is regulated post-transcriptionally.
鸟氨酸脱羧酶（ODC）和多胺（腐胺、亚精胺和精胺）对细胞增殖至关重要。最近，ODC活性升高和多胺水平升高被认为是人类结肠癌的生物学标志物。在本研究中，我们测量了从癌区分离的人结肠细胞与相邻正常结肠组织相比的ODC活性以及多胺（腐胺、亚精胺、精胺和尸胺）和乙酰腐胺的水平。此外，还比较了两组之间的ODC mRNA表达。我们发现，与从相邻正常结肠黏膜分离的结肠细胞相比，从癌区分离的结肠细胞的ODC活性、腐胺、亚精胺、精胺和尸胺水平的平均值分别显著高出1480%、470%、260%、380%和510%。癌性结肠细胞和正常结肠细胞之间的乙酰腐胺水平没有差异。在三个配对样本中的两个样本中，癌性结肠细胞中ODC mRNA的稳态水平相对于正常结肠细胞略有升高。然而，ODC mRNA水平的增加不足以解释ODC活性的增加，这表明结肠细胞ODC活性是在转录后受到调节的。
