Feb 12, 2009
Bringing Life to Man-Made Tissues
Using Cotton Candy to Create Routes for Blood-flow
A lollipop at the end of a doctor's visit may ease the sobs of a crying child, but now, researchers hope to use other sugary structures with the hope of healing patients. A team of physicians and scientists from NewYork-Presbyterian Hospital/Weill Cornell Medical Center in New York City and Cornell University in Ithaca, New York, may have developed a way to create engineered tissue that is better accepted by the body. Currently, engineered tissues are used to take the place of damaged tissue due to injury, burns or from surgical procedures. However, they are limited in size and often die from a lack of blood supply that provides life-giving nutrients.
"For decades, the lack of a suitable blood supply has been the major limitation of tissue engineering," explains Dr. Jason Spector, a plastic surgeon at NewYork-Presbyterian/Weill Cornell and assistant professor at Weill Cornell Medical College. "Without a network of blood vessels, only small, thin swaths of engineered tissue have longevity in the body."
Using crystalline sugar, scientists created a network of tiny tubes to act as tunnels, capable of shuttling nutrition-rich blood between the body's natural tissue and an artificial graft. To create the sugar fibers, researchers at The Cornell NanoScale Science & Technology Facility in Ithaca used a common cotton candy machine. Results from the project have been published in the most recent online issue of the journal Soft Matter.
A polymer is then poured over this matrix. Once hardened, the implant is soaked in warm water, dissolving the sugars, and leaving behind a web of three-dimensional hollow micro-channels. The study is in very early stages and is not yet approved for clinical use. However, promising early findings show that this novel method successfully infuses the implant with life-giving blood. The goal is to allow for the development of larger and more complex implants, fed by a person's own circulatory system.
Collaborators on the project include Drs. Leon M. Bellan and Harold G. Craighead, from the School of Applied and Engineering Physics at Cornell University.
Two Genes Play Crucial Role in Breast Cancer
Blocking Genes Prevent Metastasis
Scientists from Weill Cornell Medical College have discovered the role of two recently identified genes in promoting breast cancer metastasis. They believe their findings are important for patients, who die more often from late-stage cancer that spreads to other organs and tissues, than from their primary breast tumor.
The findings, published in the Feb. 2 issue of Cancer Cell, show that cancer cell migration and metastasis was halted after blocking the function of the two genes, called Ora1 and STIM1. When their function is not blocked, these genes allow calcium to enter into the cell, which amplifies cell locomotion, replication and growth.
To make their findings, Dr. Xin-Yun Huang, senior author and a professor of physiology and biophysics, and Dr. Shengyu Yang, the study's first author, experimented on samples of human breast tissues removed from metastatic cancer tumors. In laboratory experiments, they found that blocking the two genes prevented cell migration. The same cancer cells were then labeled with fluorescent markers, in order to track the cells within the body, and injected into fatty tissues of mice that resemble human breast tissues. The investigators found that the spreading of these cells was stopped within mice whose Ora1 and STIM1 genes were blocked, just as found in the laboratory experiments.
These findings are very exciting because the authors consider them to constitute a big step toward creating a therapeutic agent that would block the function of these genes and thus prevent or slow breast cancer metastasis in humans. Dr. Huang adds that preliminary data show that within metastatic breast cancer tissues there is also a higher expression of these two genes, reinforcing the view of their roles and of their usefulness as therapeutic targets.
NewYork-Presbyterian Hospital/Weill Cornell Medical Center
NewYork-Presbyterian Hospital/Weill Cornell Medical Center, located in New York City, is one of the leading academic medical centers in the world, comprising the teaching hospital NewYork-Presbyterian and Weill Cornell Medical College, the medical school of Cornell University. NewYork-Presbyterian/Weill Cornell provides state-of-the-art inpatient, ambulatory and preventive care in all areas of medicine, and is committed to excellence in patient care, education, research and community service. Weill Cornell physician-scientists have been responsible for many medical advances — from the development of the Pap test for cervical cancer to the synthesis of penicillin, the first successful embryo-biopsy pregnancy and birth in the U.S., the first clinical trial for gene therapy for Parkinson's disease, the first indication of bone marrow's critical role in tumor growth, and, most recently, the world's first successful use of deep brain stimulation to treat a minimally-conscious brain-injured patient. NewYork-Presbyterian, which is ranked sixth on the U.S.News & World Report list of top hospitals, also comprises NewYork-Presbyterian Hospital/Columbia University Medical Center, Morgan Stanley Children's Hospital of NewYork-Presbyterian, NewYork-Presbyterian Hospital/Westchester Division and NewYork-Presbyterian Hospital/The Allen Pavilion. Weill Cornell Medical College is the first U.S. medical college to offer a medical degree overseas and maintains a strong global presence in Austria, Brazil, Haiti, Tanzania, Turkey and Qatar. For more information, visit www.nyp.org and www.med.cornell.edu.