Artificially introduced aneuploid chromosomes assume a conserved position in colon cancer cells - PubMed (original) (raw)

Artificially introduced aneuploid chromosomes assume a conserved position in colon cancer cells

Kundan Sengupta et al. PLoS One. 2007.

Abstract

Background: Chromosomal aneuploidy is a defining feature of carcinomas. For instance, in colon cancer, an additional copy of Chromosome 7 is not only observed in early pre-malignant polyps, but is faithfully maintained throughout progression to metastasis. These copy number changes show a positive correlation with average transcript levels of resident genes. An independent line of research has also established that specific chromosomes occupy a well conserved 3D position within the interphase nucleus.

Methodology/principal findings: We investigated whether cancer-specific aneuploid chromosomes assume a 3D-position similar to that of its endogenous homologues, which would suggest a possible correlation with transcriptional activity. Using 3D-FISH and confocal laser scanning microscopy, we show that Chromosomes 7, 18, or 19 introduced via microcell-mediated chromosome transfer into the parental diploid colon cancer cell line DLD-1 maintain their conserved position in the interphase nucleus.

Conclusions: Our data is therefore consistent with the model that each chromosome has an associated zip code (possibly gene density) that determines its nuclear localization. Whether the nuclear localization determines or is determined by the transcriptional activity of resident genes has yet to be ascertained.

PubMed Disclaimer

Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Figure 1

Figure 1

A: Schematic representation of the experimental design. DLD-1 (parental cell line) was subjected to MMCT to generated derivative cell lines DLD-1+7, DLD-1+18 and DLD-1+19. 3D-FISH was performed on each of the derivative cell lines with the probe combinations indicated. B: Table showing comparisons of DNA content and gene density between Chromosome 7, 18 and 19.

Figure 2

Figure 2

Representative maximum intensity projection of confocal image stacks from DLD-1 parental and derived nuclei. A–C: Parental DLD-1 nuclei. D: DLD-1+7 nuclei. E: DLD-1+18 nuclei. F: DLD-1+19 nuclei. DAPI: DNA counterstain; CT-7: Chromosome 7; CT-18: Chromosome 18; CT-19: Chromosome 19; Merge: merged image of DAPI and chromosome territories.

Figure 3

Figure 3

A: Maximum intensity projection of a representative confocal image stack with Chromosome territories 7 (Red, Spectrum orange) and 19 (Green, Rhodamine Green) from DLD-1+19 B: A 3D reconstruction of the nucleus and chromosome territories from the image shown in A (X-Y orientation). C: A scheme adopted for 3D distance measurements of chromosome territories in Red (R1 and R2) and Green (G1, G2, and G3) from the geometric center of the nucleus (Nc), to the nuclear periphery (NP). Points on the nuclear periphery (eg. NpR1) are extensions from the nuclear center through the geometric center of the chromosome territory. D: 3D reconstruction in B shown in X-Z orientation.

Figure 4

Figure 4

Radial distance measurement profiles of chromosome territories in A: DLD-1 B: DLD-1+7, C: DLD-1+18 and D: DLD-1+19. X-axis: Radial Distance (%); Y-axis: Frequency (%); 0 or origin: center of the nucleus; 100%: nuclear periphery; Red: Chromosome 7; Green: Chromosome 19; Blue: Chromosome 18.

Figure 5

Figure 5

Raw distributions of 3D-distance measurements. CT-7 in DLD-1 & DLD-1+7, CT-18 in DLD-1 & DLD-1+18, CT-19 in DLD-1 & DLD-1+19. X-axis: cell line, Y-axis: Normalized radial distance (%) of chromosome territories from the geometric center of the nucleus.

Similar articles

Cited by

References

    1. Croft JA, Bridger JM, Boyle S, Perry P, Teague P, et al. Differences in the localization and morphology of chromosomes in the human nucleus. J Cell Biol. 1999;145:1119–1131. - PMC - PubMed
    1. Parada LA, McQueen PG, Misteli T. Tissue-specific spatial organization of genomes. Genome Biol. 2004;5:R44. - PMC - PubMed
    1. Tanabe H, Muller S, Neusser M, von Hase J, Calcagno E, et al. Evolutionary conservation of chromosome territory arrangements in cell nuclei from higher primates. Proc Natl Acad Sci U S A. 2002;99:4424–4429. - PMC - PubMed
    1. Mayer R, Brero A, von Hase J, Schroeder T, Cremer T, et al. Common themes and cell type specific variations of higher order chromatin arrangements in the mouse. BMC Cell Biol. 2005;6:44. - PMC - PubMed
    1. Ried T, Knutzen R, Steinbeck R, Blegen H, Schrock E, et al. Comparative genomic hybridization reveals a specific pattern of chromosomal gains and losses during the genesis of colorectal tumors. Genes Chromosomes Cancer. 1996;15:234–245. - PubMed

Publication types

MeSH terms

LinkOut - more resources