Features | Partner Sites | Information | LinkXpress
Sign In
GLOBETECH PUBLISHING LLC
GLOBETECH PUBLISHING LLC
GLOBETECH MEDIA

Loss of Specific MicroRNA Spurs Drug Resistance in Breast Cancer Cells

By BiotechDaily International staff writers
Posted on 17 May 2012
A study determined that development of resistance to the chemotherapeutic drug tamoxifen by breast tumors was due to the disappearance of a specific microRNA.

MicroRNAs are snippets of about 20 nucleotides that block gene expression by attaching to molecules of messenger RNA (mRNA) in a fashion that prevents them from transmitting the protein synthesizing instructions they had received from the DNA.

In the study, investigators at the German Cancer Research Center (Heidelberg, Germany) related genome-wide miRNA microarray analyses of breast tumors to the appearance in the tumors of resistance to tazmoxifen.

They reported in the April 16, 2012, online edition of the journal Oncogene that the microRNA miRNA-375 was among the top downregulated miRNAs in resistant cells. Reexpression of miR-375 was sufficient to resensitize tumor cells to tamoxifen and partly reversed the epithelial–mesenchymal transition (EMT), which is characteristic of tumor cells.

A combination of mRNA profiling, bioinformatics analysis, and experimental validation identified the protein metadherin (MTDH) as a direct target of miR-375. Metadherin is an oncogenic protein that is normally blocked by miR-375. The importance of MTDH was confirmed in experiments with tumor cells that lacked the MTDH gene. In these tumors, even in the absence of miR-375, no resistance to tamoxifen arose.

“The analysis of microRNAs in breast cancer has put us on the track of metadherin. We will possibly be able to specifically influence the cancer-promoting properties of this protein in the future,” said coauthor Dr. Stefan Wiemann, associate professor of molecular genome analysis at the German Cancer Research Center. “Resistances to drugs are the main reason why therapies fail and disease progresses in many cancers. We want to understand what goes on in the cells when this happens so we can develop better therapies in the future.”

Related Links:

German Cancer Research Center



WATERS CORPORATION

Channels

Drug Discovery

view channel
Image: Star-like glial cells in red surround alpha-beta plaques in the cortex of a mouse with a model of Alzheimer\'s disease (Photo courtesy of Strittmatter laboratory/Yale University).

Experimental Cancer Drug Reverses Symptoms in Mouse Model of Alzheimer's Disease

An experimental, but clinically disappointing drug for treatment of cancer has been found to be extremely effective in reversing the symptoms of Alzheimer's disease (AD) in a mouse model.... Read more

Lab Technologies

view channel
Image: The gene assembly robot, the GeneTheatre (Photo courtesy of Analytik Jena AG).

Genomic Research Laboratories Await New Compact Liquid Handling System

A small footprint benchtop liquid handler that automates multiple gene assembly tasks and associated procedures such as PCR setup is now available for use by biotech and genomic research laboratories.... Read more

Business

view channel

NanoString and MD Anderson Collaborate on Development of Novel Multi-Omic Expression Profiling Assays for Cancer

The University of Texas MD Anderson Cancer Center (Houston, TX, USA) and NanoString Technologies, Inc. (Seattle, WA, USA) will partner on development of a revolutionary new type of assay—simultaneously profiling gene and protein expression, initially aiming to discover and validate biomarker signatures for immuno-oncology... Read more
 

Events

27 May 2015 - 28 May 2015
02 Jun 2015 - 03 Jun 2015
15 Jun 2015 - 18 Jun 2015
Copyright © 2000-2015 Globetech Media. All rights reserved.