all Raghu Kalluri stories

Dinosaur protein preserved over time

50443248 — Fri, 01 May 2009 20:08:29 -0400

Ancient protein dating back 80 million years to the Cretaceous geologic period has been preserved in bone fragments and soft tissues of a type of duck-billed dinosaur, according to a study in the May 1 issue of Science.

Led by scientists at Beth Israel Deaconess Medical Center (BIDMC) and North Carolina State University (NCSU), the new findings support earlier results from analyses suggesting that collagen protein survived in the bones of a well-preserved Tyrannosaurus rex, and offer robust new evidence supporting previous conclusions that birds and dinosaurs are evolutionarily related.

Bone-marrow-derived stem cells can reverse genetic kidney disease

70652986 — Mon, 26 Mar 2007 06:26:56 -0400

The discovery that bone-marrow derived stem cells can regenerate damaged renal cells in an animal model of Alport syndrome provides a potential new strategy for managing this inherited kidney disease and offers the first example of how stem cells may be useful in repairing basement membrane matrix defects and restoring organ function.

Led by researchers at Beth Israel Deaconess Medical Center (BIDMC), the findings are described in the Proceedings of the National Academy of Sciences (PNAS), which appeared on-line the week of April 24, 2006.

Symptoms of Alport syndrome, the second-most common genetic cause of kidney failure, usually appear in children, affecting the kidneys' filtration system and typically leading to end-stage renal disease in the patient's teens, 20s or 30s. The disease additionally causes deafness in some patients.

"This is one of 31 human diseases that occur because of genetic defects in the body's extracellular matrix and basement membrane proteins," explains the study's senior author, Raghu Kalluri, PhD, chief of the division of matrix biology at BIDMC and associate professor of medicine at Harvard Medical School.

Many have 'cancer,' but few progress to true disease

70652986 — Mon, 26 Mar 2007 07:10:20 -0400

Folkman and Kalluri suggest that most tumors don't develop a blood supply that allows them to grow and progress to cancer, because people produce natural inhibitors of blood vessel growth, or angiogenesis. They write that a better understanding of these inhibitors may yield a new generation of nontoxic anticancer drugs that could be given preventively to people at high risk for developing the disease.

The essay cites autopsy studies revealing that more than a third of women aged 40 to 50 have small breast carcinomas, whereas only 1 percent are diagnosed with clinical breast cancer. Analagous findings hold for prostate cancer in men. Similarly, autopsies show that virtually all people aged 50 to 70 have small thyroid tumors, yet well below 1 percent are diagnosed with clinical thyroid cancer.

Folkman and Kalluri describe two phases of cancer, the first of which isn't inherently lethal and where genetic mutations develop that transform normal cells in the body into cancerous cells. The second phase involves the dominance of growth factors secreted by a tumor to attract a blood supply over the defense provided by natural angiogenesis inhibitors.

A major current focus of Folkman's Vascular Biology Program at Children's Hospital Boston is on predicting the 'angiogenic switch' and delaying or preventing it with natural angiogenesis inhibitors. Preventive therapy could be offered to people with a genetically increased risk for cancer, people with a family history of cancer, and people whose cancer has been treated but may recur.

Cell surface proteins can have pro- and anti-angiogenic face

70652986 — Mon, 26 Mar 2007 05:18:49 -0400

Angiogenesis is the process by which cancer tumors develop a network of blood vessels to feed them, so that they may continue their growth. The strategy that cancer cells use to attract blood vessels to them involves a series of chemical messages. Researchers think of this as a type of cellular kidnapping, luring the blood cells with growth factors, which one writer describes as a kind of "biological candy." According to theory, if cells were treated in a way that they were immune to the lure of the growth factors, then angiogenesis would stop and cancer tumors would die. Much research is going on in this area. However, a Harvard Medical School research team has discovered that things aren't quite that simple.

Researchers explain how protein inhibits growth of blood vessels

70652986 — Mon, 26 Mar 2007 05:16:41 -0400

Thirty years ago, Judah Folkman, of Children's Hospital Boston and Harvard Medical School, first developed the idea that cancerous tumors are dependent on the growth of small blood vessels. Since then, Folkman and other researchers have sought a way to block the growth of cancer tumors through restricting or eliminating the small blood vessels that feed them. A new discovery made by a team of researchers working at Beth Israel Deaconess Medical Center (BIDMC) in Boston offers one of the first explanations for how angiogenesis – the medical term for the growth of small blood vessels – is inhibited in the body. The study focuses on a protein called tumstatin. Senior author Raghu Kalluri is a researcher in the Department of Medicine and the Program in Matrix Biology at BIDMC and associate professor at Harvard Medical School. The study appeared in the Jan. 4, 2002, issue of Science. “This is a very important advance in the fields of angiogenesis research and cancer biology,” said Folkman. The study was supported in part by grants from the National Institutes of Health (NIH) and research funds from Beth Israel Deaconess Medical Center.