Engelhard H H
Department of Surgery, Northwestern University Medical School, Chicago, Illinois 60611.
Cell Mol Biol (Noisy-le-grand). 1993 Sep;39(6):607-20.
The c-myc protein was one of the first proto-oncogene products to be linked to the increased proliferative activity of neoplastic cells. However, few studies have attempted to quantify changes occurring in cellular c-myc protein content in response to growth-inhibitory conditions, or to relate such changes to total cellular protein (TCP) levels, %S phase cells and/or cellular growth balance. Knowledge of such relationships is important for determining the biological relevance of the c-myc protein as a marker for proliferating cells. In this study, a dual-laser flow cytometric technique employing three fluorescent dyes was used to quantify cellular changes in c-myc protein, TCP, DNA and growth balance in exponentially-growing and serum deprived U118MG, A-172 and HL-60 cells. Results obtained by flow cytometry were verified using other techniques. Changes in c-myc protein content were found to occur independently of changes in TCP, %S phase or cellular growth balance, and varied between cell lines. These results indicate that cellular c-myc protein determinations convey information that is unique from other indicators of cellular growth and proliferation. Such information may be linked, however, to the nutritional status and origin of the cells being assayed.
c-myc蛋白是最早被发现与肿瘤细胞增殖活性增加相关的原癌基因产物之一。然而，很少有研究试图量化在生长抑制条件下细胞c-myc蛋白含量的变化，或将这些变化与细胞总蛋白（TCP）水平、S期细胞百分比和/或细胞生长平衡联系起来。了解这些关系对于确定c-myc蛋白作为增殖细胞标志物的生物学相关性很重要。在本研究中，采用一种使用三种荧光染料的双激光流式细胞术技术，来量化指数生长和血清剥夺的U118MG、A-172和HL-60细胞中c-myc蛋白、TCP、DNA和生长平衡的细胞变化。通过流式细胞术获得的结果使用其他技术进行了验证。发现c-myc蛋白含量的变化独立于TCP、S期百分比或细胞生长平衡的变化，并且在细胞系之间有所不同。这些结果表明，细胞c-myc蛋白的测定传达了与细胞生长和增殖的其他指标不同的独特信息。然而，这些信息可能与被检测细胞的营养状态和来源有关。
