Department of Histology and Embryology, Nicolaus Copernicus University in Torun Collegium Medicum in Bydgoszcz, Karlowicza 24, 85-092 Bydgoszcz, Poland.
Cell Biol Int. 2014 Jul;38(7):857-67. doi: 10.1002/cbin.10290. Epub 2014 May 6.
Increased levels of cyclin D1 and amplification of CCND1 gene occur in many types of cancers. We have followed the expression of cyclin D1 after treatment with doxorubicin with reference to cell death and other possible therapeutic implications. The effect of the treatment on the cell cycle, survival, intracellular level (flow cytometry), and intracellular localization of cyclin D1 (fluorescence microscopy) and expression of CCND1 (real-time RT-PCR) was investigated in HL-60 cells. An increase in the fluorescence intensity of cyclin D1 occurred after treatment with 0.15 and 0.3 μM doxorubicin. This tendency was confirmed by real-time RT-PCR. Expression of CCND1 in relation to the reference gene PBGD was increased in cells exposed to 0.15 μM doxorubicin. Concomitantly, some alterations in the regulation of the G0/G1, S, and G2/M checkpoints occurred, accompanied by changes in the polyploid fraction of the population. This was particularly evident at 0.3 μM doxorubicin, at which concentration the rate of cell death was also clearly higher. In conclusion, depending on the concentration used, alterations in cell death and the number of S, G2/M, and polyploid cells may correspond with cyclin D1 levels. This, in turn, may reflect an important role of the protein as one of the possible survival/point-of-no-return regulators dependent on its concentration, which seems especially plausible in the context of more prominent cell death in the above-mentioned fractions of cells.
cyclin D1 水平升高和 CCND1 基因扩增发生在许多类型的癌症中。我们已经观察到阿霉素治疗后 cyclin D1 的表达情况，以参考细胞死亡和其他可能的治疗意义。我们研究了阿霉素治疗对 HL-60 细胞的细胞周期、存活、细胞内水平（流式细胞术）、cyclin D1 的细胞内定位（荧光显微镜）和 CCND1 表达（实时 RT-PCR）的影响。用 0.15 和 0.3 μM 阿霉素处理后，cyclin D1 的荧光强度增加。实时 RT-PCR 证实了这一趋势。与 PBGD 参考基因相比，暴露于 0.15 μM 阿霉素的细胞中 CCND1 的表达增加。同时，G0/G1、S 和 G2/M 检查点的调控发生了一些变化，伴随着群体中多倍体分数的变化。在 0.3 μM 阿霉素时尤为明显，此时细胞死亡率也明显升高。总之，根据所用浓度的不同，细胞死亡和 S、G2/M 和多倍体细胞数量的变化可能与 cyclin D1 水平相对应。这反过来又可能反映了该蛋白作为可能的生存/不可逆转调节因子之一的重要作用，这取决于其浓度，在上述细胞亚群中更明显的细胞死亡背景下，这种作用似乎尤为合理。
