Israeli scientists are closer than ever to finding a way to beat back cancer at the Technion Israel Institute of Technology. The findings of the new study were published last week in the journal CELL.
The researchers discovered two cancer-suppressing proteins, according to information released via PR Newswire. They carried out the study in the world-famous laboratory of Nobel Prize laureate Professor Aaron Ciechanover, president of the Israel Cancer Society.
The team was led by research associate Dr. Yelena Dravtsova-Ivantsiv and worked together with physicians from Rambam, Carmel and Hadassah Medical Centers, all of whom are studying tumors and their treatments.
KPC1 – a vital pathway in the life of the cell – is responsible for the degradation of defective proteins that could damage the cell if not removed. The system tags these defective proteins and send them to the proteasome cellular complex to be destroyed.
The system also removes functional and healthy proteins that are no longer needed, thus regulating the processes the proteins control.
By the time a protein reaches the proteasome system it is already broken down but there are exceptions.
This study examined “p105” – a long precursor of a key regulator in a cell called “NF-kB” which has been identified as a link between inflammation and cancer.
The first person to suggest such a link was Dr. Rudolph Virchow, a German pathologist, in 1863. His research has been repeatedly confirmed over the years, and since the discovery of NF-kB 30 years ago, there have been many articles linking the cell to malignant transformation in tumors in various parts of the body.
The current research is focused on deciphering the decision-making mechanism that determines which process will be applied to the NF-kB cell. There are two, both connected to the “ubiquitin system” which produces a protein that greatly restricts the development of cancerous tumors.
1. Either a “ubiquitin” system component called KPC1 becomes involved and attaches ubiquitin to p105, thus shortening the protein to become “p50” ; or 2. Ubiquitination is mediated without KPC1 and instead by another component in the system, and p105 is degraded and destroyed completely.
In other words, the presence of high levels of KPC1 and p50 would mean the malignant growth is suppressed and healthy tissue appears to be protected, according to the present findings in the study.
The current research was conducted on lab mice as well as samples of human tumors. A strong connection was found between the suppression of malignancy and the level of the two proteins.
Professor Aaron Ciechanover, president of the Israel Cancer Society, noted that many more years will be required “to establish the research and gain a solid understanding of the mechanisms behind the suppression of the tumors. The development of a drug based on this discovery is a possibility, although not a certainty, and the road to such a drug is long and far from simple.”
Ciechanover won the Nobel Prize in chemistry in 2004, together with Professors Avram Hershko (also from Technion) and Irwin Rose of the Fox Chase Cancer Center, for the discovery of the ubiquitin system. The current line of research is a continuation of that work.Hana Levi Julian