Identification of hundreds of conserved and nonconserved human microRNAs.

MicroRNAs are noncoding RNAs of approximately 22 nucleotides that suppress translation of target genes by binding to their mRNA and thus have a central role in gene regulation in health and disease. To date, 222 human microRNAs have been identified, 86 by random cloning and sequencing, 43 by computational approaches and the rest as putative microRNAs homologous to microRNAs in other species. To prove our hypothesis that the total number of microRNAs may be much larger and that several have emerged only in primates, we developed an integrative approach combining bioinformatic predictions with microarray analysis and sequence-directed cloning.

MicroRNA expression detected by oligonucleotide microarrays: system establishment and expression profiling in human tissues.

MicroRNAs (MIRs) are a novel group of conserved short approximately 22 nucleotide-long RNAs with important roles in regulating gene expression. We have established a MIR-specific oligonucleotide microarray system that enables efficient analysis of the expression of the human MIRs identified so far. We show that the 60-mer oligonucleotide probes on the microarrays hybridize with labeled cRNA of MIRs, but not with their precursor hairpin RNAs, derived from amplified, size-fractionated, total RNA of human origin.

Changes in cytokine production and impaired hematopoiesis in patients with anorexia nervosa: the effect of refeeding.

The changes in cytokines and hormones involved in hematopoiesis were studied in the serum of 7 girls with anorexia nervosa, 15-24 yr old, on admission and after 5% and 10% weight gain. Hematopoiesis was studied by in-vitro culturing of circulating granulocyte-macrophage colony forming cells and erythroid burst forming cells. Nutritional status was studied by anthropometric measurements and resting energy expenditure.

Bone marrow-derived factors support growth of N-type, but not of melanocytic neuroblastoma cells.

Background: Neuroblastoma and melanoma cells have a common embryonal origin. In contrast to melanoma, most neuroblastoma tumours preferentially metastasize into bone marrow. Previously, we described that bone marrow-conditioned medium (BM-CM) supports the proliferation of catecholamine-producing (N-type) neuroblastoma (SK-N-SH, IMR-32, Kelly)-, but not of melanoma cells.

Human bone marrow-derived mitogenic stimulation selective for breast carcinoma and neuroblastoma cells.

In patients with neuroblastoma (NB) or breast carcinoma (BC), metastatic disease in the bone marrow (BM) is observed more frequently than at any other site, and a high incidence of BM metastases in these patients is associated with advanced disease and poor prognosis. These observations suggest the presence of BM micro-environmental elements that are favorable for NB and BC tumor cell growth. The influence of normal human BM cell-derived conditioned medium (CM) on clonogenic growth of BC and NB cell lines was investigated in vitro.