Asai T.1, Tsuchiya Y.1, Kajiwara-Asai K.1, Baez S.2, Tello A.3, Yamamoto T.4, Yamamoto M.1.
1Department of Clinical Engineering and Medical Technology, Niigata University of Health and Welfare, Niigata, Japan; 2Department of Surgery, Sótero del Río Hospital, Santiago, Chile; 3A nursing student from Universidad Iberoamericana de Ciencias y Tecnología, Santiago, Chile; 4Department of Structural Pathology, Institute of Nephrology, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan.
Introduction: Gallbladder cancer does not cause specific symptoms in its early stage, but if detected early, it has an excellent prognosis. Diagnostic markers are needed for early detection of cancer. Objectives: We aimed to detect specific proteins as biomarkers for the early detection of gallbladder cancer in Chile or the assessment of tumor grade. Methods: Our operating procedure is as follows: preparation of paraffin sections from formalin-fixed paraffin-embedded gallbladder cancer tissue blocks, deparaffinization, excision of tissue section by laser microdissection, on-site direct digestion with trypsin, purification of peptides using the C18 Stage Tip, measurement of the peptide concentration by modified bicinchoninic acid protein assay, LC MS/MS analysis. Results: A total of 15 samples were collected: 3 from normal controls (group I), 6 from cancer tissues (group II), and 6 from advanced cancer tissues (group III). The average numbers of detected proteins from each group were 993, 1291, and 1105, respectively. Among these proteins, the numbers of group-specific proteins were 306, 1,148, and 930, respectively. The number of proteins detected in both groups I and III (91) was much smaller than the number detected in both groups I and II (266) or both groups II and III (696). Conclusion: Our results suggest that new biomarkers for early detection of gallbladder cancer may be found among the proteins detected in this study.