In a recent issue of Oncogene (journal impact factor 7.135), two project leaders at the Centre for Cancer Biomedicine and Institute for Cancer Research, cancer geneticist Guro E. Lind (Ragnhild A. Lothe's group) and cell biologist Camilla Raiborg (Harald Stenmark's group), present a promising biomarker for early detection of colon cancer.
Colorectal cancer is one of the most common cancer forms and has a high mortality. Since this cancer can be effectively cured when detected at an early stage, there is considerable interest in identification of biomarkers that can be used in non-invasive tests for early detection of colorectal cancer.
Guro E. Lind identified a very promising biomarker for early detection of colorectal cancer, the gene SPG20, whose promoter is hypermethylated in colorectal adenomas (premalignant stage) and carcinomas but not in normal colonic epithelium. Promoter hypermethylation leads to silencing of the gene so that transcription is inhibited.
Camilla Raiborg discovered that the protein encoded by SPG20, Spartin, is a regulator of normal cell division, and that cancer cells that lack Spartin tend to be connected by intercellular membrane bridges. Reversal of SPG20 methylation increases Spartin levels and reverses the cell division phenotype. This is exciting since it is already known that faulty cell division can represent an early step in carcinogenesis and raises the possibility that SPG20 hypermethylation is both a biomarker and a mechanism in colon carcinogenesis.
How can these discoveries benefit the future cancer patient?
Preliminary results suggest that it is possible to detect SPG20 silencing in stool samples from cancer patients, which opens the possibility of using SPG20 detection as an early diagnostic tool. Knowing that cell division defects are typical for a subgroup of colorectal cancers can enable us to design therapies aimed at killing such cells.
This study involved several prominent clinicians at Oslo University Hospital and illustrates the value of collaborations between clinicians, translational scientists and cell biologists.
SPG20, a novel biomarker for early detection of colorectal cancer, encodes a regulator of cytokinesis.
Lind GE, Raiborg C, Danielsen SA, Rognum TO, Thiis-Evensen E, Hoff G, Nesbakken A, Stenmark H, Lothe RA.
Oncogene. 2011 Apr 18.
Home page of "Membrane-associated protein dynamics in cell division" project group, led by Camilla Raiborg & Hilde Abrahamsen