Nuclear Matrix Association in Proliferative and Invasive Cytotrophoblasts

Abnormal trophoblast invasion is associated with the most common and most severe complications of human pregnancy. The biology of invasion, as well as the etiology of abnormal invasion remains poorly understood. The aim of this study was to characterize the transcriptome of the HTR-8/SVneo human cytotrophoblast cell line which displays well characterized invasive and non-invasive behaviors, and to correlate the activity of the transcriptome with nuclear matrix attachment and cell phenotype. Interestingly comparison of the transcriptome did not reveal an obvious significant difference between the transcriptomes of invasive and non-invasive HTR cells. In contrast, comparison of the MARs on chromosomes 14-18 revealed an increased number of MARs associated with an invasive phenotype. These attachment areas were more likely to be associated with silent (rather than actively transcribed) genes. DNA extraction with a 2 M NaCl solution followed by restriction digestion with EcoR1 facilitates the separation of matrix bound DNA from non matrix bound DNA. Genomic CGH arrays were used to map the relative differences between attached (scaffold/matrix) and non-attached (loop) portions of the genome in non-invasive (proliferative) and invasive trophoblasts. The matrix association was assessed relative to gene expression measured on Illumina expression beadchips.