A new study published in the February 2008 print edition of The FASEB Journal describes a scientific advance that should reduce the cost and increase the availability of a wide range of drugs. In the report, University of Pennsylvania researchers describe how they used gene therapy to reduce the time it takes to breed large animals capable of producing therapeutic proteins in their milk, such as insulin or those that fight cancer. This represents a significant milestone in drug development, as current methods involve cloning, which takes more time and generally costs more.
“Having an easier way to harness nature’s power to produce large quantities of specific proteins in milk could increase the availability of drugs for people who could otherwise not afford these treatments,” said Ina Dobrinski, one of the researchers on the study.
The study also is significant because it may also be a new way to eliminate diseases in future generations of animals, such as those used for livestock. Here’s why: To get the goats to produce specific proteins, the researchers used radiation to kill a portion of a male goat’s germ cells (the cells that produce sperm). Then they used a modified adeno-associated virus (a well studied and tolerated gene therapy vector) to insert a gene in the remaining cells.
Once the new gene took hold in the germ cells, a predictable number of female offspring produced the desired protein in their milk. The advance is immediately valuable for pharmaceutical development and biology research, but a similar approach could be used to bolster the food supply by eliminating genetic disorders in animals over several generations. It is also possible that once perfected, this technique could eliminate disease genes in humans over several generations, assuming ethical concerns can be resolved adequately.
“For thousands of years, people have domesticated cows and goats to make milk, butter and cheese. And for thousands of years dairy products have been used as folk remedies for practically every human illness. Most have been completely ineffective.” said Gerald Weissmann, MD, editor-in-chief of The FASEB Journal. “So it is reassuring that modern science would find a way to use the milk we drink to yield of drugs that actually work.”
Source: Federation of American Societies for Experimental Biology
Related stories:
Cells lining milk ducts hold key to spread of common form of breast cancer
When a form of cancer that begins in the milk ducts of the breast invades neighboring tissue to spread to other parts of the body, the cause lies not in the tumor cells themselves but in a group of abnormal surrounding cells that cause the walls of the duct to deteriorate like a rusty pipe, according to a new study led by Dana-Farber Cancer Institute researchers.
Researchers find stem cell marker controls 2 key cancer pathways
Researchers at Georgetown University Medical Center have discovered that a gene associated with human breast stem cells can stimulate development of mammary cells by activating two critical cancer pathways. They say this finding, reported at the annual meeting of the American Association for Cancer Research (AACR), provides new evidence that breast cancer can arise from stem cells and that targeting this gene might provide a new way to treat cancers of the breast as well as other tumor types.
A protein that triggers aggressive breast cancer
SATB1 is a nuclear protein well known for its crucial role in regulating gene expression during the differentiation and activation of T cells, making it a key player in the immune system. But SATB1 has now revealed a darker side: it is an essential contributing factor in the most aggressive forms of breast cancer.
Findings point to molecular 'Achilles heel' for half of breast cancer tumors
Researchers at Lombardi Comprehensive Cancer Center at Georgetown University Medical Center have shown why a protein known as cyclin D1 may be the Achilles heel for breast tumors that are estrogen receptor positive (ER+) − which is the most common type of breast cancer.
New 'knock-out' gene model provides molecular clues to breast cancer
New insights into the role of estrogen receptor in mammary gland development may help scientists better understand the molecular origin of breast cancer, according to new research from the University of Cincinnati (UC).
Discovery suggests location of genes for breast density, a strong risk factor for breast cancer
Studying the DNA of 889 people, gene hunters at the Mayo Clinic and H. Lee Moffitt Cancer Centers have identified a region on chromosome 5p that is significantly associated with dense breast tissue, a known risk factor for breast cancer. The findings, published in the September 1 issue of
Cancer Research, a publication of the American Association for Cancer Research, suggest that genes which influence breast density could serve as a predictive marker for disease and provide a biological target for agents that may reduce breast cancer risk by reducing breast density.
Toxic milk
In the August 1 issue of G&D, Dr. Ronald Evans (Salk Institute) and colleagues report on their discovery that mutations in the mouse gene encoding PPARã adversely affect lactation milk quality, and have serious health consequences for nursing pups.
Researchers discover evidence of very recent human adaptation
A Cornell study of genome sequences in African-Americans, European-Americans and Chinese suggests that natural selection has caused as much as 10 percent of the human genome to change in some populations in the last 15,000 to 100,000 years, when people began migrating from Africa.