Ke Eileen, Patel Bhavinkumar B, Liu Tiffany, Li Xin-Ming, Haluszka Oleh, Hoffman John P, Ehya Hormoz, Young Nancy A, Watson James C, Weinberg David S, Nguyen Minhhuyen T, Cohen Steven J, Meropol Neal J, Litwin Samuel, Tokar Jeffrey L, Yeung Anthony T
From the Divisions of *Basic Science, daggerMedical Science, and double daggerPopulation Science, Fox Chase Cancer Center, Philadelphia, PA.
Pancreas. 2009 Mar;38(2):e33-42. doi: 10.1097/MPA.0b013e318193a08f.
There are currently no diagnostic indicators that are consistently reliable, obtainable, and conclusive for diagnosing and risk-stratifying pancreatic cysts. Proteomic analyses were performed to explore pancreatic cyst fluids to yield effective diagnostic biomarkers.
We have prospectively recruited 20 research participants and prepared their pancreatic cyst fluids specifically for proteomic analyses. Proteomic approaches applied were as follows: (1) matrix-assisted laser-desorption-ionization time-of-flight mass spectrometry peptidomics with LC/MS/MS (HPLC-tandem mass spectrometry) protein identification; (2) 2-dimensional gel electrophoresis; (3) GeLC/MS/MS (tryptic digestion of proteins fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified by LC/MS/MS).
Sequencing of more than 350 free peptides showed that exopeptidase activities rendered peptidomics of cyst fluids unreliable; protein nicking by proteases in the cyst fluids produced hundreds of protein spots from the major proteins, making 2-dimensional gel proteomics unmanageable; GeLC/MS/MS revealed a panel of potential biomarker proteins that correlated with carcinoembryonic antigen (CEA).
Two homologs of amylase, solubilized molecules of 4 mucins, 4 solubilized CEA-related cell adhesion molecules (CEACAMs), and 4 S100 homologs may be candidate biomarkers to facilitate future pancreatic cyst diagnosis and risk-stratification. This approach required less than 40 microL of cyst fluid per sample, offering the possibility to analyze cysts smaller than 1 cm in diameter.
目前尚无始终可靠、可获取且具有决定性意义的诊断指标用于胰腺囊肿的诊断和风险分层。进行蛋白质组学分析以探索胰腺囊肿液，从而获得有效的诊断生物标志物。
我们前瞻性招募了20名研究参与者，并专门制备他们的胰腺囊肿液用于蛋白质组学分析。应用的蛋白质组学方法如下：（1）采用液相色谱/串联质谱（HPLC-串联质谱）蛋白质鉴定的基质辅助激光解吸电离飞行时间质谱肽组学；（2）二维凝胶电泳；（3）凝胶内酶解/串联质谱（通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分离蛋白质后进行胰蛋白酶消化，并通过液相色谱/串联质谱鉴定）。
对350多种游离肽进行测序表明，外肽酶活性使囊肿液的肽组学不可靠；囊肿液中的蛋白酶导致蛋白质切口，从主要蛋白质产生数百个蛋白质斑点，使得二维凝胶蛋白质组学难以处理；凝胶内酶解/串联质谱揭示了一组与癌胚抗原（CEA）相关的潜在生物标志物蛋白。
淀粉酶的两种同源物、4种粘蛋白的可溶分子、4种与CEA相关的可溶细胞粘附分子（CEACAMs）以及4种S100同源物可能是有助于未来胰腺囊肿诊断和风险分层的候选生物标志物。这种方法每个样本所需的囊肿液少于40微升，为分析直径小于1厘米的囊肿提供了可能性。
