BACKGROUND/ OBJECTIVES: The detection of cancer-specific DNA in peripheral blood, known as a liquid biopsy, has been reported recently. Most such studies have used plasma as a sample; however, whether or not serum can be used as effectively is unclear. We attempted to clarify suitable samples for detecting KRAS mutations in circulating DNA in the blood of pancreatic cancer patients using droplet digital polymerase chain reaction (PCR). METHODS: DNA was extracted from the tissue, plasma, and serum of 40 pancreatic cancer patients. The presence of KRAS mutations G12D, G12V, and G12R was analyzed by droplet digital PCR. RESULTS: The amount of DNA isolated from the serum was much higher than that from plasma (1.0- to 42.0-fold). At least 1 KRAS mutation was observed in 93% of cancer tissues, whereas we detected the mutations in only 48% of the serum and plasma DNA samples. The G12D mutation was the most prevalent of the three mutations, followed by the G12V mutation. The presence of the G12D KRAS mutation in the plasma, serum, or tissue did not correlate to the overall survival; however, the prognosis of the patients with a KRAS mutation at G12V in the plasma or serum was significantly poorer than that of the patients without the mutation (P < 0.01). CONCLUSIONS: Serum and plasma were found to be good materials for detecting cancer-specific DNA in the peripheral blood and the presence of KRAS mutations in blood-derived DNA may be used as a prognostic biomarker for patients with pancreatic cancer.
BACKGROUND/ OBJECTIVES: The detection of cancer-specific DNA in peripheral blood, known as a liquid biopsy, has been reported recently. Most such studies have used plasma as a sample; however, whether or not serum can be used as effectively is unclear. We attempted to clarify suitable samples for detecting KRAS mutations in circulating DNA in the blood of pancreatic cancerpatients using droplet digital polymerase chain reaction (PCR). METHODS: DNA was extracted from the tissue, plasma, and serum of 40 pancreatic cancerpatients. The presence of KRAS mutations G12D, G12V, and G12R was analyzed by droplet digital PCR. RESULTS: The amount of DNA isolated from the serum was much higher than that from plasma (1.0- to 42.0-fold). At least 1 KRAS mutation was observed in 93% of cancer tissues, whereas we detected the mutations in only 48% of the serum and plasma DNA samples. The G12D mutation was the most prevalent of the three mutations, followed by the G12V mutation. The presence of the G12DKRAS mutation in the plasma, serum, or tissue did not correlate to the overall survival; however, the prognosis of the patients with a KRAS mutation at G12V in the plasma or serum was significantly poorer than that of the patients without the mutation (P < 0.01). CONCLUSIONS: Serum and plasma were found to be good materials for detecting cancer-specific DNA in the peripheral blood and the presence of KRAS mutations in blood-derived DNA may be used as a prognostic biomarker for patients with pancreatic cancer.
Authors: Claudio Luchini; Nicola Veronese; Alessia Nottegar; Vera Cappelletti; Maria G Daidone; Lee Smith; Christopher Parris; Lodewijk A A Brosens; Maria G Caruso; Liang Cheng; Christopher L Wolfgang; Laura D Wood; Michele Milella; Roberto Salvia; Aldo Scarpa Journal: Cancers (Basel) Date: 2019-08-10 Impact factor: 6.639
Authors: Miles W Grunvald; Richard A Jacobson; Timothy M Kuzel; Sam G Pappas; Ashiq Masood Journal: Int J Mol Sci Date: 2020-10-16 Impact factor: 5.923