ENOX2 as a biomarker for the diagnosis of pancreatic cancer

Pancreatic cancer is a significant health burden. 80% of pancreatic cancers are diagnosed at Stage III / IV. 5-year survival of patients diagnosed at Stage IV is less than 1%, with median survival ~6 months, compared with patients diagnosed with localised disease who have up to 25% 5-year survival rates. This project will focus on the development of assays for a promising cancer biomarker for use in prostate cancer, Enox2.
While rarely detected in plasma from healthy individuals, Enox2 has been detected in plasma in a range of malignancies, including breast, pancreas (1), renal, gastric and colon cancers. It is thought that Enox2 proteins are expressed soon after the onset of malignancy and so are detectable at a relatively early stage of cancer development. For example, in a small study of malignant mesothelioma, Enox2 was detectable in the serum 4-10 years prior to diagnosis (2).
Intriguingly, Enox2 has been shown to exist in multiple isoforms (3), with each isoform seemingly specific for a particular tissue type of origin. This makes generation of a standard Enox2 immunoassay potentially problematic. However, it also provides an opportunity in that, if we can develop methods which distinguish and quantify these isoforms, tumour type-specific assays which are robust to isoform expression changes can be developed, and ultimately could also provide a tissue-of-origin test for early-stage cancers.
While standard immunoassays are therefore inappropriate for Enox2 measurements as they lack isoform-scale resolution, mass spectrometry (MS) provides a strong candidate platform for the development of such an assay. We have previously shown that assays can be developed which can distinguish between and quantify highly similar proteins and splice variants (4), and improvements in MS technology including speed and sensitivity of analysis and automation of sample preparation means that MS has the potential to carry such assays into a clinical setting.
In this project, the student will seek to characterise the Enox2 isoforms in pancreatic cancer cell lines compared to other common cancer types, and then develop a specific and sensitive MS-based assay to determine its levels in plasma. This assay will subsequently be tested in a cohort of pancreatic cancer samples and healthy controls, including individuals with Stage I, III and IV disease to assess the value of Enox2 measurement for pancreatic cancer detection.