Detecting pancreatic cancer through blood tests

Pancreatic ductal adenocarcinoma (PDAC) makes up 95% of all pancreatic cancer cases and has the lowest survival rate, and early diagnostic methods have yet to be developed. As a result, diagnosis often comes at a later stage when treatment options are limited and prognosis is poor.

Diagnosis at this stage often comes from imaging techniques followed by tissue biopsies, which are not appropriate options to use as standardised, early screening methods. New ways to diagnose PDAC at an earlier stage are needed, without the use of invasive procedures.

Liquid biopsies are becoming a more popular option to fill this demand. Taking a blood sample is minimally invasive, quick, and can tell us a lot of information about a person from their cfDNA (cell free DNA). cfDNA is released from cells and circulates in the blood, containing information about the cell they come from.

Methylation on cfDNA often appears in cancer patients, making it an effective biomarker that can be used to diagnose the presence of cancer with high accuracy and specificity about the cancer (such as location). The concept has many applications, including in the earlier diagnosis of PDAC.

The identification of these biomarkers in blood is often limited to the technology used, with DNA being damaged by the harsh chemicals that are used in the processing. The recent development of TAPS technology at the University of Oxford has helped to overcome this, using a bisulphate-free method, and making it a perfect method for PDAC biomarker identification.

DPhil students Paulina Siejka-Zielinska and Felix Jackson and Postdoctoral Researcher Jingfei Chang from Dr Chunxiao Song’s lab in collaboration with Dr Shivan Sivakumar (consultant medical oncologist) have been investigating TAPS as a method to identify PDAC biomarkers. Using blood samples from PDAC patients and healthy individuals, they are applying TAPS technology to prove that it can be used to accurately detect pancreatic cancer biomarkers in cfDNA.

Preliminary results from this study suggest that cfDNA methylation can be used for the identification of PDAC, as well as being able to accurately distinguish between pancreatic cancer and other pancreatic disorders that effect the DNA, such as pancreatitis.

If this is the case, then the results from this study will make for solid grounds for the application of TAPS in the earlier screening for pancreatic cancer.

About the Song Lab

The Song Lab combine various chemical biology and genome technologies to develop novel tools to analyse the epigenome. The lab apply these tools to two main research areas: the use of epigenetic modifications in circulating cell-free DNA from the blood for non-invasive disease diagnostics including early detection of cancer, and understanding the contribution of epigenetic heterogeneity in cancer development.

Most recently, the TAPS technology developed at the Song Lab has led to the creation of the start up Base Genomics, which has been launched to set a new gold standard in DNA methylation detection using this TAPS technology. Base Genomics will initially focus on developing a blood test for early-stage cancer and minimal residual disease. You can read more about it here.