The Orion Colorectal Cancer Risk Test is a simple blood test that detects an epigenetic abnormality, the loss of imprinting of the cancer-associated growth gene, IGF2 (“IGF2 Biomarker”). Our test is being developed to identify people at increased risk of developing colorectal cancer (“CRC”) who will benefit from early CRC screening. Screening allows physicians to identify and remove precancerous polyps and prevent future colon cancer. Preclinical studies suggest that individuals who are positive by our test may also benefit from treatment with a novel class of drugs in development.1 When clinical trials are completed, we will market the Orion CRC Risk Test to the 81.6 million people in their 20’s and 30’s in the United States and to the primary care physicians who treat them.
Between 65% and 85% of all colorectal cancer cases are sporadic (non-heritable) and occur in people who are not being aggressively screened and who are classified as having an average risk of developing colorectal cancer according to the existing stratification criteria.3 Currently, risk tests on the market today are only able to identify people at risk of developing rare hereditary colorectal cancer syndromes, which are responsible for only 1-3% of all CRC cases. We are developing the Orion CRC Risk Test to help physicians identify patients who are at risk of developing sporadic CRC. Orion has a worldwide exclusive license to a broad estate of issued and pending patents covering imprinting abnormalities of the insulin-like growth factor II gene (“IGF2”) from The Johns Hopkins University School of Medicine.
|Childhood Cancers||Adult Cancers|
|Acute lymphoblastic leukemia||Bladder||Chronic Myelogenous Leukemia|
|Hepatocellular||Renal Cell Carcinoma|
|Acute Myelogenous Leukemia||Testicular Germ Cell|
Adapted from Falls, et al AJP 154, 635-647 (1999)
Genomic imprinting is a rare but important mechanism of gene regulation where one copy of the gene (an “allele”) is normally expressed and the other allele is silenced through epigenetic marks of parental origin.14 For example, the imprinting of a gene can be maternal, resulting in the expression of the paternal allele and silencing of the maternal allele. IGF2 is normally imprinted in human tissues. In 1993, scientists at the Johns Hopkins University School of Medicine discovered that normally imprinted genes including IGF2 can “lose their imprint” resulting in the expression of both copies of the gene, and this can lead to human disease.13 IGF2 is a growth promoting gene, and evidence is mounting that individuals whose peripheral blood leukocytes (“PBL”) exhibit loss of imprinting of IGF2 (the IGF2 Biomarker) may be at elevated risk for developing colorectal cancer.8, 9
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