Publications by authors named "Reena Buurman"

Background: In hepatocellular carcinoma (HCC), histone deacetylases (HDACs) are frequently overexpressed. This results in chromatin compaction and silencing of tumor-relevant genes and microRNAs. Modulation of microRNA expression is a potential treatment option for HCC.

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Background: Germline mutations in BRCA1/2 significantly contribute to hereditary breast and/or ovarian cancer. Here, we report a novel BRCA2 duplication of exons 22-24 in a female patient with bilateral breast cancer at age 35 and 44. The duplicated region was initially detected by gene panel sequencing and multiplex ligation-dependent probe amplification.

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Aim: To screen clinically relevant microRNAs (miRNAs) silenced by DNA methylation in human hepatocellular carcinoma (HCC).

Methods: Knockdown of DNA methyltransferases (DNMTs) using siRNAs and miRNA profiling in HCC cell lines were performed to identify DNA hypermethylation-mediated miRNA downregulation. Confirmation using individual quantitative real-time PCR (qRT-PCR) assays was then performed followed by DNA methylation quantification at the promoter of the miRNA genes.

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Background & Aims: Modulation of microRNA expression is a potential treatment for hepatocellular carcinoma (HCC). Therefore, the epigenetically regulated microRNA-449 family (miR-449a, miR-449b, miR-449c) was characterized with regards to its functional effects and target genes in HCC.

Methods: After transfection of miR-449a, miR-449b, and/or miR-449c, tumor-relevant functional effects were analyzed using in vitro assays and a xenograft mouse model.

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Background: Histone deacetylation, a common hallmark in malignant tumors, strongly alters the transcription of genes involved in the control of proliferation, cell survival, differentiation and genetic stability. We have previously shown that HDAC1, HDAC2, and HDAC3 (HDAC1-3) genes encoding histone deacetylases 1-3 are upregulated in primary human hepatocellular carcinoma (HCC). The aim of this study was to characterize the functional effects of HDAC1-3 downregulation and to identify functionally important target genes of histone deacetylation in HCC.

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Background & Aims: Histone deacetylation regulates chromatin remodeling and transcriptional down-regulation of specific genomic regions; it is altered in many types of cancer cells. We searched for microRNAs (miRs) that are affected by histone deacetylation and investigated the effects in hepatocellular carcinoma (HCC) cells.

Methods: HCC cell lines (HepG2, HLE, HLF, and Huh7) and immortalized liver cell lines (THLE-2 and THLE-3) were incubated with the histone deacetylase inhibitor trichostatin A.

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Objectives: This study aimed to identify microRNAs as novel biomarkers for improved diagnosis, prognosis prediction, and as a therapeutic target for pancreatic cancer. microRNAs may have a general role by acting as superordinated key regulators of tumorigenesis.

Methods: Individual cellular molecules of multiple pathways associated with pancreatic cancer were analyzed for common microRNA binding sites, thereby enabling the identification of key regulating microRNAs.

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Background: Array-based comparative genomic hybridization (array-CGH) is an emerging high-resolution and high-throughput molecular genetic technique that allows genome-wide screening for chromosome alterations. DNA copy number alterations (CNAs) are a hallmark of somatic mutations in tumor genomes and congenital abnormalities that lead to diseases such as mental retardation. However, accurate identification of amplified or deleted regions requires a sequence of different computational analysis steps of the microarray data.

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Dedifferentiation of hepatocellular carcinoma implies aggressive clinical behavior and is associated with an increasing number of genomic alterations, eg deletion of 13q. Genes directly or indirectly deregulated due to these genomic alterations are mainly unknown. Therefore this study compares array comparative genomic hybridization and whole genome gene expression data of 23 well, moderately, or poorly dedifferentiated hepatocellular carcinoma, using unsupervised hierarchical clustering.

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