Method and kit for the detection of biliary tract cancer

Abstract

The present invention provides a method for detecting biliary tract cancer by measuring the amounts of APOA2 protein variants in a test sample with anti-APOA2 antibodies, the anti-APOA2 antibodies for use in the above method and a detection kit for biliary tract cancer including the above antibodies.

1 . A method for detecting biliary tract cancer by determining an amount of an APOA2 protein variants in body fluid sample from a test subject and a normal subject, the method comprising:
 (A) measuring an APOA2-ATQ protein amount of an APOA2-ATQ protein in the sample using an anti-APOA2-ATQ terminus antibody specifically binding to an APOA2-ATQ C-terminal region of the APOA2-ATQ protein comprising the amino acid sequence of SEQ ID NO:1 and an aniti-APOA2-ATQ non-terminus antibody binding to the APOA2-ATQ protein other than to the APOA2-ATQ C-terminal region;   (B) measuring an APOA2-AT protein amount of an APOA2-AT protein in the sample using an anti-APOA2-AT terminus antibody specifically binding to an APOA2-AT C-terminal region of the APOA2-AT protein comprising the amino acid sequence of SEQ ID NO:2 and an aniti-APOA2-AT non-terminus antibody binding to the APOA2-AT protein other than to the APOA2-AT C-terminal region;   (C) inputting to a preset formula for a discriminant value, the measurement of the amounts of the APOA2-ATQ protein and the amounts of the APOA2-AT protein obtained in the steps (A) and (B) to obtain a discriminant value of each the test subject and the normal subject, and   (D) comparing the discriminant value of the test subject with that the normal subject to determine that the test subject is affected with biliary tract cancer when the discriminant value of the test subject is statistically significantly different with that of the normal subject.   
     
     
         2 . The method according to  claim 1 , wherein the C-terminal regions of the APOA2-ATQ protein and the APOA2-AT protein comprise a sequence consisting of 6 or more consecutive amino acids including the C-terminus of each protein. 
     
     
         3 . The method according to  claim 1 , wherein the preset formula is any one selected from the group consisting of a logistic regression equation, a formula generated by support vector machine analysis, a formula generated by neural network analysis, and a formula generated by discriminant analysis. 
     
     
         4 . The method according to  claim 1 , wherein the preset formula expressed as the logistic regression equation is any one of:
   a×(APOA2-ATQ)+b×(APOA2-AT)+d,  Formula 1:
     a×(APOA2-ATQ)+b×(APOA2-AT)+c×[(APOA2-ATQ)×(APOA2-AT)]+d, or  Formula 2:
     c×[(APOA2-ATQ)×(APOA2-AT)]+d,  Formula 3:
   wherein each of a, b, c and d is an optional real number except zero, APOA2-ATQ represents the measurement of the amount of the APOA2-ATQ protein, and APOA2-AT represents a measurement of the amount of the APOA2-AT protein.   
     
     
         5 . The method according to  claim 4 , wherein the discriminant value of the test subject obtained by the logistic regression equation is two thirds or less of the discriminant value of the normal subject. 
     
     
         6 . The method according to  claim 1 , wherein the body fluid sample is blood, plasma, or serum. 
     
     
         7 . The method according to  claim 2 , wherein the body fluid sample is blood, plasma, or serum. 
     
     
         8 . The method according to  claim 3 , wherein the body fluid sample is blood, plasma, or serum. 
     
     
         9 . The method according to  claim 4 , wherein the body fluid sample is blood, plasma, or serum. 
     
     
         10 . The method according to  claim 5 , wherein the body fluid sample is blood, plasma, or serum. 
     
     
         11 . The method according to  claim 1 , wherein the biliary tract cancer is early biliary tract cancer. 
     
     
         12 . The method according to  claim 2 , wherein the biliary tract cancer is early biliary tract cancer. 
     
     
         13 . The method according to  claim 3 , wherein the biliary tract cancer is early biliary tract cancer. 
     
     
         14 . The method according to  claim 4 , wherein the biliary tract cancer is early biliary tract cancer. 
     
     
         15 . The method according to  claim 5 , wherein the biliary tract cancer is early biliary tract cancer.