Biomarker 'M2-PK' Identified as Key Enzyme in Cancer Diagnosis and Therapy
Warburg hypothesis (named after the Nobel prize winner) confirmed
Cancer cells can be recognized by their metabolism
Scientists from Harvard Medical School in Boston report on the enzyme 'M2-PK' in a study in the renowned specialist journal 'Science'
Tests for detecting M2-PK in blood or also in stool samples are already available
Extremely promising new compounds target 'M2-PK'
Cancer research is facing a radical change of direction. Cancer cells do not obtain their energy from the breakdown of sugar to carbon dioxide and water, but from energy-rich intermediates of sugar metabolism instead. This confirms the hypothesis developed by the German Noble prizewinner Otto Warburg over 80 years ago, that an altered energy production in human metabolism is characteristic of cancer. The key enzyme 'M2-PK' (PKM2) hereby plays a decisive role, as scientists from Harvard Medical School report in the current issue of the world-renowned specialist magazine 'Science'.
The results of these experiments represent a significant change in direction in the field of cancer research. They also confirm the earlier findings of scientists such as Warburg, Eigenbrodt and Mazurek that tumor cells express their own characteristic isoform of the glycolytic key enzyme pyruvate kinase. M2-PK is the synonym for both the dimeric and also the tetrameric forms of the M2 pyruvate kinase isoenzyme (also known as PKM2). The dimeric form of M2-PK is dominant in tumor cells.
A simple commercial test is already available to measure the biomarker M2-PK in stool and blood
M2-PK in stool samples can be used to screen for bowel (colorectal) cancer and in blood for monitoring therapy response and patient follow-up of various cancers. Effective and simple tests are already available for the detection of this enzyme, which have been developed and patented by the company ScheBo Biotech AG situated in Giessen, Germany, and are already marketed as commercial test kits.
Biomarker M2-PK in stool samples for the screening and early detection of bowel cancer and polyps
Clinical studies from Germany, Great Britain and Ireland, which tested M2-PK in stool samples as a metabolic marker for the early detection of bowel cancer, show detection rates between 78% and 97%. That means that in the various studies between 78 and 97 people out of every 100 people with bowel cancer are detected by the M2-PK Stool Test. For polyps >1cm the detection rate lay at 60%; for polyps <1cm it was 25%. The sensitivity for all polyps was 40%.
It is therefore possible to detect bowel polyps as well as bowel tumors with high sensitivity using the biomarker 'M2-PK' in fecal samples, without the need to detect blood in the stool. The result is not affected by diet or specific foods, so a special diet is not required. There are no false positive results from hemorrhoids or other sources of bleeding into the bowel. The test can detect non-bleeding as well as bleeding bowel polyps or tumors. These scientific findings represent a change in direction in the early detection and screening for polyps and cancer of the bowel.
M2-PK in blood as a biomarker for therapy response and patient follow-up in various cancers
Studies from research groups around the world have shown that the concentration of M2-PK is significantly increased in the blood of patients with renal, lung, breast,cervical and gastrointestinal (colon, rectal, gastric [stomach], pancreatic, oesophageal) tumors, as well as melanoma, and correlates with the severity of the disease.
The monitoring of patients receiving therapy is an important application for the detection of M2-PK in EDTA-plasma, which assists with the early recognition of the success or failure of a therapy and in predicting the chances of recovery.
Newly developed compounds which target 'M2-PK' successfully block cancer metabolism
ScheBo Biotech AG is not only a pharmaceutical biotech company which is active in the development of in-vitro diagnostics, but has also already developed extremely promising candidate compounds targeted against 'M2-PK' which sequentially block cancer metabolism. Significant successes in blocking cancer cells have already been achieved in preclinical studies with these innovative compounds. The company is extremely confident that a fundamental breakthrough has been achieved with this new approach, according to board members Dr. Ursula Scheefers-Borchel and Dr. Hans Scheefers.
Source: Science 17 September 2010: Vol. 329. no. 5998, pp. 1492 - 1499; DOI: 10.1126/science.1188015