Title:
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Early detection of pancreatic cancer : use of genetic and proteomic approaches
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Aims of the investigation
The aims of this investigation were to detect pancreatic cancer earlier using both
genetic and proteomic approaches.
The aims of the genetic approach were to use Amplification Refractory Mutation
System (ARMS) to detect KRAS mutations in blood serum and plasma, pancreatic juice
and tissue from patients with pancreatic cancer, chronic pancreatitis and other benign
disease controls.
The aims of the proteomic approach were to use Isobaric Tags for Relative and
Absolute Quantification (iTRAQ) to identify and quantify the proteins present in blood
serum from patients with 'early' and 'later' stage pancreatic cancer, chronic pancreatitis
and healthy controls. In this thesis 'early' stage pancreatic cancer was defined as
patients with lymph node negative status while 'later' stage pancreatic cancer was
defined as patients with lymph node positive status.
Results achieved
DNA extraction from blood serum and plasma, pancreatic juice and tissue was
successful. DNA concentrations were higher in pancreatic juice compared with serum
and plasma. DNA concentrations were higher in serum compared with plasma. KRAS
mutations were detected in 71.7 % of pancreatic cancer patients in pancreatic juice
samples, 51.9 % in serum samples, 45.1 % in plasma samples and 79 % in pancreatic
tissue samples. KRAS mutations were detected in 42.9 % of chronic pancreatitis
patients in pancreatic juice samples, 43.8 % in serum samples and 20 % in plasma
samples.
A total of 254 proteins were identified and 234 proteins were quantified using
iTRAQ in serum from early and later stage pancreatic cancer patients, chronic
pancreatitis patients and healthy controls. Of these proteins, 48 showed a greater than
3-fold change between the early stage pancreatic cancer group and controls. Of these
proteins, three were selected for further analysis: von Willebrand Factor, Collagen I and
Collagen Ill. Further validation using Western blotting and ELlSA verified the iTRAQ
result for von Willebrand Factor that this protein was elevated in the early stage
pancreatic cancer group compared with controls.
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