A Taxing Issue: How Human T-lymphotropic Virus Can Cause Leukemia In Adults

Jan 31, 2008

Researchers have identified a potential new mechanism through which human T-lymphotropic virus type-1 (HTLV-1) causes leukemia in adults. The findings, published this week in the online open access journal Retrovirology, represent the first time that a reduction in histone protein levels has been linked to viral infection and the development of cancer.

HTLV-1 is a retrovirus that causes adult T-cell leukaemia/lymphoma (ATLL). A single protein made by the virus, Tax, is thought to be enough to trigger cancer development. Tax has a number of effects in the cell, including promoting inappropriate cell division, repressing DNA repair mechanisms and causing genomic instability. These effects are thought to combine and cause cancer, although the exact details of the process are unclear.

James Bogenberger and Paul Laybourn from Colorado State University, USA found that the levels of histone proteins and histone transcripts were lower in T-cell lines infected with HTLV-1 than in uninfected cell lines. They also showed that Tax could cause a drop in the levels of histone transcript in uninfected cells.

Histone proteins are required for the packaging of DNA in cell nuclei and are involved in many key processes associated with DNA, including transcription, repair and replication. The authors suggest that Tax uncouples cell division and replication-dependent histone gene expression, allowing cell division to continue while the levels of histone protein fall.

They write: “We suggest Tax repression of replication-dependent histone gene expression will result in reactivation of viral gene expression, deregulation of cellular gene expression and genomic instability. All of these effects may contribute to the development of adult T-cell leukemia/lymphoma. To our knowledge, this is the first example of a reduction of histone levels correlating with viral infection and cancer development.”

Source: BioMed Central

Explore further: One route to malaria drug resistance found

add to favorites email to friend print save as pdf

Related Stories

Nucleoids and the structure of life

Jul 07, 2014

(Phys.org) —In the brave new world of three-parent embryos several inherited mitochondrial diseases can potentially be solved. One slightly dubious argument used by its champions to assuage equally dubious ...

Recommended for you

One route to malaria drug resistance found

12 minutes ago

Researchers have uncovered a way the malaria parasite becomes resistant to an investigational drug. The discovery, at Washington University School of Medicine in St. Louis, also is relevant for other infectious ...

Protein therapy successful in treating injured lung cells

32 minutes ago

Cardiovascular researchers at The Ohio State University Wexner Medical Center have successfully used a protein known as MG53 to treat acute and chronic lung cell injury. Additionally, application of this protein proved to ...

User comments : 0