Clinical diagnostics startup Euclid Diagnostics has been awarded a Phase I Small Business Innovation Research grant from the National Cancer Institute to support the development of a diagnostic test to detect prostate cancer from urine DNA.
More specifically, the company seeks to develop a secondary prostate cancer diagnostic test that can be performed on men with elevated levels of prostate-specific antigen in order to identify patients in need of prostate biopsies, according to a recently published grant abstract.
Euclid is based at the Purdue Technology Center of the Purdue Research Park of Northwest Indiana. The Phase I SBIR grant, worth approximately $288,000, commenced last month and will expire at the end of May 2014.
The principal investigator on the grant is Euclid CSO Diha Freije, who declined to comment on the project as the company awaits peer-reviewed publication of related research.
According to the grant's abstract, more than 1 million prostate biopsies are performed in the US each year to diagnose as many as 200,000 cases of prostate cancer. The majority of these biopsies are performed needlessly.
Euclid has identified 12 novel markers that are methylated in prostate cancer, and has developed detection assays using both quantitative PCR and a proprietary technique called termination-coupled linear amplification, or TCLA.
There is little in the literature on this method. However, in a US patent application, No. 20110097728, entitled "Materials and method for assaying for methylation of CpG islands associated with genes in the evaluation of cancer," Euclid describes the TCLA method in some detail.
Generally, the patent's claims state, the method includes incubating a DNA sample under deaminating conditions to thereby produce a deaminated DNA sample, which can be purified. This deaminated sample is used as a template to amplify a target sequence or target sequences that include one or more CpG islands or portions of one or more CpG islands, thereby producing one or more amplified target sequences, which can also be purified.
These amplified target sequences are then linearly amplified in the presence of a primer and a dideoxynucleotide to generate one or more fragments of different lengths, each of which corresponds to the distance in bases from the 5' end of the primer to the position where the dideoxynucleotide is incorporated, the patent explains. These fragments are then analyzed to determine their lengths, which can subsequently be used to determine the methylation status of methylated cytosines within the amplified target sequences.
According to the company's grant abstract, TCLA offers improved sensitivity and specificity when applied to DNA from limited sources such as circulating DNA.
An assay based on the analysis of methylated markers "should reduce the number of repeat biopsies by at least 50 percent and is commercially valuable as an additional tool to improve prostate cancer diagnosis," Euclid wrote.
In its prospective SBIR-funded study, the company proposes to analyze the methylation of the panel of markers in urine DNA from patients with elevated PSA.
"If we successfully detect prostate cancer with 85 percent sensitivity and specificity, we will undertake a large validation study during Phase II in preparation for a clinical trial," the company said.
Euclid previously was awarded US Patent No. 8,361,724, "Methods for evaluating the methylation status of a polynuclotide," and No. 7,449,291, "Methods of copying the methylation pattern of DNA during isothermal amplification and microarrays."