Methods and compositions for diagnosing breast cancer

Abstract

Mammastatin has an approximate molecular weight of 44 kDa in its inactive, non-phosphorylated form. Normal mammary cells express functional phosphorylated forms having approximate molecular weights of 53 kDa and 49 kDa. Metastatic mammary cells either do not express Mammastatin at all, or do not express the 53 kDa or 49 kDa, phosphorylated forms. Mammary cancer cells are inhibited in their growth by the administration of phosphorylated Mammastatin.

1 . A method comprising the steps of:
 a) determining an amount of mammastatin present in a patient's sample, wherein said mammastatin is a polypeptide having an approximate molecular weight of 5310 when phosphorylated and is produced by normal human mammary cells or a polypeptide produced by normal breast cancer cells and specifically reactive with monoclonal antibody 7G6 produced from hybridoma ATCC No. HB10152;   b) comparing the amount of determined mammastatin to a control, said control comprising an amount of mammastatin from a normal, non-breast cancer female; and   c) correlating an amount of mammastatin less than the control with the presence of, or predisposition to, breast cancer.   
     
     
         2 . The method according to  claim 1  wherein the predisposition to breast cancer is an indication of an increased risk of developing breast tumors. 
     
     
         3 . The method according to  claim 1 , wherein the sample comprises mammary tissue, mammary cells, or fluids from the patient. 
     
     
         4 . The method according to  claim 1  where, in the step of obtaining, the sample comprises blood or blood serum from the patient. 
     
     
         5 . The method according to  claim 1 , where the step of determining comprises use of an immunoassay. 
     
     
         6 . The method according to  claim 5  wherein the immunoassay is a Western blot. 
     
     
         7 . The method according to  claim 5  wherein the immunoassay is a dot blot. 
     
     
         8 . The method according to  claim 5  wherein the immunoassay is an enzyme-linked immunosorbent assay. 
     
     
         9 . The method according to  claim 1 , wherein the control comprises an amount of mammastatin of at least 10 ng/ml. 
     
     
         10 . The method according to  claim 9 , wherein the control comprises an amount of mammastatin in the range of 10 ng/ml to 50 ng/ml. 
     
     
         11 . The method according to  claim 9 , wherein the control comprises 10 ng/ml of mammastatin. 
     
     
         12 . The method according to  claim 1  wherein the control comprises normal human mammary cells. 
     
     
         13 . The method according to  claim 1  wherein the control comprises control comprises mammary cells, or mammary tissue, or fluid obtained from a normal, non-breast cancer female. 
     
     
         14 . A method for diagnosing a patient, comprising the steps of:
 a) quantifying an amount of mammastatin in a first and a second sample of the patient's mammary cells, mammary tissue, or fluids, wherein a) said mammastatin is a polypeptide having an approximate molecular weight of 53 kD when phosphorylated and is produced by normal human mammary cells or a polypeptide produced by normal breast cancer cells and specifically reactive with monoclonal antibody 7G6 produced from hybridoma ATCC No. HB10152, and b) the second sample is obtained after the first sample;   b) comparing the amount of mammastatin in the first sample with the amount mammastatin in the second sample; and   c) correlating a decrease in the amount of mammastatin in the second sample with the presence of, or predisposition to, breast cancer.   
     
     
         15 . A method comprising the steps of:
 a) determining an amount of mammastatin present in a patient's sample, wherein said mammastatin is a polypeptide having an approximate molecular weight of 53 kD when phosphorylated and is produced by normal human mammary cells or a polypeptide produced by normal breast cancer cells and specifically reactive with monoclonal antibody 7G6 produced from hybridoma ATCC No. HB10152; and   c) correlating an amount of mammastatin less than about 10 ng/ml with the presence of, or predisposition to, breast cancer.   
     
     
         16 . A kit comprising:
 a) a reagent composition comprising monoclonal antibody 7G6, said monoclonal antibody produced from hybridoma ATCC No. HB10152 and able to specifically bind mammastatin, a polypeptide produced by normal human mammary cells having an approximate molecular weight of about 53 kD when phosphorylated, wherein said reagent composition is configured and arranged to allow for quantitation of mammastatin in a sample; and   b) a protein standard comprising mammastatin, wherein said standard is configured and arranged to allow for quantitation of the amount of said mammastatin in a sample.