Grants and Contributions:

Grant or Award spanning more than one fiscal year. (2017-2018 to 2022-2023)

Precision medicine is a relatively new activity in the field that concentrates on the disease experienced by a particular patient. Conditions vary from patient to patient because of genetic and environmental factors. A key component of this area of medicine is the assay of progression of a specific disease including the possibility for early detection. This involves the quantitative determination of biomarkers for the disease as they appear ion blood, urine and tissue samples. Biomarkers are species , for example, that are released by tumors that signal the presence of particular disease such as cancer, whether of a genetic of infectious type. This proposal describes research towards the assay of such moieties in human serum using biosensor technology. The latter involves the binding of the target biomarker at the surface of an electronic transducer. In the proposed work, such a device will be based on ultra-high frequency acoustic physics. A special component of this type of detection is the capability for operation in fluids such serum where large scale interference from proteins is anticipated. This proposal includes a strategy to prevent this deleterious effect.
Two overall applications of the technology are described - one is the early stage detection of ovarian cancer via the 2 known biomarkers, lysophosphatidic (LPA) and heat shock protein 10 (HSP-10). The second is the analogous detection of a biomarker connected to the process of metastasis in the context of the inception of breast cancer. With respect to LPA the probe will be the protein gelsolin which will be attached to an antifouling acoustic wave sensor surface. This will in turn will be subjected to nano-gold particle attachment with actin. The sensor will then detect LPA directly in human serum via replacement of the labeled actin. For HSP-10 the probe will be aptamers developed for this purpose in the Thompson lab. Stage 1 through 4 patient samples are available from Princess Margaret Hospital in Toronto through an official agreement. Values from biosensor detection for LPA will be compared with those from LC-MS.
The biosensor assay for the metastasis product, parathyroid hormone related peptide (PTHrP), will involve a sandwich assay. The probe in this case is an antibody fragment for the hormone. This will trap the target from serum and for subsequent interaction with gold particlee labeled antibody. This approach is very common in ELISA technology. Again, sample from breast cancer patients are available from St. Michael's Hospital by official agreement.