Transgenomic, Inc. (OTC Bulletin Board: TBIO) today announced completion of a development study of several new assays to detect genetic mutations using the Company's proprietary Co-amplification at Lower Denaturing Temperature PCR (COLD-PCR) technology in the Epidermal Growth Factor Receptor (EGFR) gene. EGFR mutations are found in a number of cancers, including lung and colorectal cancers. Several new targeted cancer therapeutics called tyrosine kinase inhibitors (TKIs) have been approved or are in clinical trials to be used as front line or secondary therapies against these cancers. The presence of mutations in certain regions of the EGFR gene are key criteria to determine whether or not a patient should receive TKI inhibitor therapy.
In its study, Transgenomic looked at the ability of COLD-PCR to detect EGFR mutations in exons 19-21. Study results indicate that the COLD-PCR assays detect all exon 19 deletions, the T790M mutation in exon 20 and all mutations in exon 21 in the specific regions amplified, including L858R and L861Q point mutations. The sensitivity of detection when confirmed using Sanger sequencing is 0.05% to 0.2% using plasmid and cell line DNA dilutions. Preliminary experiments on DNA isolated from plasma samples are currently underway, and early results are mimicking the plasmid and cell line DNA studies. Transgenomic's assays were developed in collaboration with the Dana-Farber Cancer Institute and a major oncology pharmaceutical partner.
Craig Tuttle, Transgenomic CEO, commented, "One of our key corporate strategic initiatives is to develop ultra-high sensitivity assays for the detection of low-level DNA mutations in body fluids. We believe COLD-PCR provides us with the analytical sensitivity and accuracy to achieve this goal. We have always believed this technology will become a tool to screen patient serum, plasma or urine samples for the early detection of cancer in order to determine which patients might benefit from a particular therapy, or to test patients with malignant disease to identify drug resistance mutations earlier in the treatment cycle. Providing clinicians with this information much earlier in the disease cycle or therapy regimen will have a significant impact on cancer diagnosis and improved outcomes in cancer treatment."
COLD-PCR is a genetic testing approach that selectively amplifies mutant DNA by recognizing that mutant DNA strands denature at lower temperatures in a PCR reaction compared with normal mutant-free DNA. Specific enhancements of the COLD-PCR methodology enable the detection of any and all of the mutations present in the region amplified. Therefore prior knowledge of specific mutations is not necessary. Using this patented technique, COLD-PCR amplifies mutant DNA with minimal amplification of the normal DNA.
Limit of Detection experiments have indicated that the mutant DNA can be detected in a plasma/serum sample when as little as five to 10 copies of mutant DNA are present. This is especially useful in detecting somatic mutations in diseases like cancer, where cells with disease-causing mutations are present at very low levels. The enhanced analytic sensitivity of COLD-PCR will allow clinicians to use smaller amounts of sample for their genetic analyses and less intrusive sample collection methods such as a blood draw for serum or plasma preparation, a urine catch, fine needle aspirate or bronchial lavage for genetic analyses. In addition, the resultant PCR-amplified fragment can be easily analyzed with Sanger sequencing or any other downstream analysis such as the allele-specific detection, next-generation sequencing or Transgenomic's proprietary WAVE platform.
Scientists map cancer mutations in EGFR gene, revealing drug resistance paths