Broader utilization of origins of DNA replication in cancer cell lines along a 78 kb region of human chromosome 2q34.
Broader utilization of origins of DNA replication in cancer cell lines along a 78 kb region of human chromosome 2q34.
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DOI：
10.1002/jcb.23336
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发表时间：
2012-01
影响因子：
4
通讯作者：
Meltzer, Paul S.
中科院分区：
文献类型：
--
作者：
Valenzuela, Manuel S.;Hu, Lan;Lueders, John;Walker, Robert;Meltzer, Paul S.
人类DNA复制依赖于分布在基因组内的数千个起始点的激活。起始点的实际分布是未知的，也不知道这种分布是否是细胞类型所特有的，或者它是否随着细胞的增殖状态而变化。在这项研究中，我们使用了基于实时PCR的新生链DNA丰度分析，以确定沿着CH2q34上78kb区域的起始点的位置。使用从HeLa和正常皮肤成纤维细胞分离的新生DNA链的初步研究表明，在这两种细胞系中，高来源活性的峰位于相似的位置。然而，在HeLa细胞中，整个起源曲线对应于广泛的起源激活区，而在成纤维细胞中，观察到更具点状的起源激活轮廓。为了研究这种不同起源分布的相关性，我们比较了乳腺癌细胞系MDA-MB-231、BT-474和MCF-7与其正常对应的MCF-10A的起源分布特征。另外，以CRL7250细胞株作为正常对照。我们的结果证实了我们早先的观察结果，并表明正常细胞系的起源轮廓呈点状，与癌细胞系中观察到的更宽的区域轮廓相反。对起始峰的定量分析表明，癌细胞中激活的起始点的数量在统计学上高于正常细胞，这表明癌细胞与正常细胞相比，其起始点使用的灵活性显著增加。
Human DNA replication depends on the activation of thousands of origins distributed within the genome. The actual distribution of origins is not known, nor whether this distribution is unique to a cell type, or if it changes with the proliferative state of the cell. In this study we have employed a real time PCR-based nascent strand DNA abundance assay, to determine the location of origins along a 78 kb region on Ch2q34. Preliminary studies using nascent DNA strands isolated from either HeLa and normal skin fibroblast cells showed that in both cell lines peaks of high origin activity mapped in similar locations. However, the overall origin profile in HeLa cells corresponded to broad origin activation zones, whereas in fibroblasts a more punctuated profile of origin activation was observed. To investigate the relevance of this differential origin profile, we compared the origin distribution profiles in breast cancer cell lines MDA-MB-231, BT-474, and MCF-7, to their normal counterpart MCF-10A. In addition, the CRL7250 cell line was also used as a normal control. Our results validated our earlier observation and showed that the origin profile in normal cell lines exhibited a punctuated pattern, in contrast to broader zone profiles observed in the cancer cell lines. A quantitative analysis of origin peaks revealed that the number of activated origins in cancer cells is statistically larger than that obtained in normal cells, suggesting that the flexibility of origin usage is significantly increased in cancer cells compared to their normal counterparts.
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DOI：
10.4161/cc.8.19.9682
发表时间：
2009-10-01
期刊：
Cell cycle (Georgetown, Tex.)
影响因子：
--
作者：
Frum RA;Khondker ZS;Kaufman DG
通讯作者：
Kaufman DG
影响因子：
14.9
作者：
Di Paola D;Rampakakis E;Chan MK;Arvanitis DN;Zannis-Hadjopoulos M
通讯作者：
Zannis-Hadjopoulos M
影响因子：
64.5
作者：
MARTIN, RG;OPPENHEIM, A
通讯作者：
OPPENHEIM, A
影响因子：
10.5
作者：
Ge, Xin Quan;Jackson, Dean A;Blow, J Julian
通讯作者：
Blow, J Julian
DOI：
10.1016/j.bbrc.2003.12.040
发表时间：
2004-01-23
影响因子：
3.1
作者：
Hu, L;Xu, X;Valenzuela, MS
通讯作者：
Valenzuela, MS