Anti-miRs competitively inhibit microRNAs in Argonaute complexes.

MicroRNAs (miRNAs), small RNA molecules that post-transcriptionally regulate mRNA expression, are crucial in diverse developmental and physiological programs and their misregulation can lead to disease. Chemically modified oligonucleotides have been developed to modulate miRNA activity for therapeutic intervention in disease settings, but their mechanism of action has not been fully elucidated. Here we show that the miRNA inhibitors (anti-miRs) physically associate with Argonaute proteins in the context of the cognate target miRNA in vitro and in vivo.

Mechanisms of single-stranded phosphorothioate modified antisense oligonucleotide accumulation in hepatocytes.

Single-stranded antisense oligonucleotides (SSOs) are used to modulate the expression of genes in animal models and are being investigated as potential therapeutics. To better understand why synthetic SSOs accumulate in the same intracellular location as the target RNA, we have isolated a novel mouse hepatocellular SV40 large T-antigen carcinoma cell line, MHT that maintains the ability to efficiently take up SSOs over several years in culture. Sequence-specific antisense effects are demonstrated at low nanomolar concentrations.

Matrix metalloproteinase (MMP)-13 regulates mammary tumor-induced osteolysis by activating MMP9 and transforming growth factor-beta signaling at the tumor-bone interface.

The tropism of breast cancer cells for bone and their tendency to induce an osteolytic phenotype are a result of interactions between breast cancer cells and stromal cells and are of paramount importance for bone metastasis. However, the underlying molecular mechanisms remain poorly understood. We hypothesize that tumor-stromal interaction alters gene expression in malignant tumor cells and stromal cells creating a unique expression signature that promotes osteolytic breast cancer bone metastasis and that inhibition of such interactions can be developed as targeted therapeutics.

Therapeutic suppression of translation initiation factor eIF4E expression reduces tumor growth without toxicity.

Expression of eukaryotic translation initiation factor 4E (eIF4E) is commonly elevated in human and experimental cancers, promoting angiogenesis and tumor growth. Elevated eIF4E levels selectively increase translation of growth factors important in malignancy (e.g.

Setting sights on the treatment of ocular angiogenesis using antisense oligonucleotides.

The application of antisense technology to study physiological and disease processes continues to mature. Antisense approaches are among the most direct means to use genomic sequence information. When developing therapeutics, applications range from early target validation in discovery to the therapeutic product.