Use of id4 for diagnosis and treatment of cancer

Abstract

Methods for diagnosis and treatment of cancer using ID4 are disclosed. Specifically, epigenetic inactivation of ID4 in colorectal carcinomas and breast correlates with poor differentiation and unfavorable prognosis. Further, aberrant hypermethylation of ID4 gene promoter region increases risk of metastasis in colorectal and breast cancer.

1 . A method of identifying a compound for treating colorectal cancer, comprising:
 providing a colorectal cancer cell that contains an ID4 gene promoter, expresses an ID4 gene, or a combination thereof;   contacting the cell with a test compound; and   determining the methylation level of the ID4 gene promoter, the expression level of the ID4 gene, or a combination thereof in the cell, wherein the methylation level of the ID4 gene promoter in the cell, if lower than a control methylation level, the expression level of the ID4 gene in the cell, if higher than a control expression level, or a combination thereof indicates that the test compound is a candidate for treating colorectal cancer.   
     
     
         2 . A method of treating colorectal cancer, comprising:
 obtaining a biological sample from a human subject;   determining the methylation level of an ID4 gene promoter in the sample;   identifying the subject as being suffering from or at risk for developing colorectal cancer if the methylation level of the ID4 gene promoter in the sample is higher than a control methylation level; and   administering to the subject an effective amount of a compound that decreases the methylation level of the ID4 gene promoter in the subject.   
     
     
         3 . A method of identifying a compound for treating breast cancer, comprising:
 providing a breast cancer cell that contains an ID4 gene promoter;   contacting the cell with a test compound; and   determining the methylation level of the ID4 gene promoter in the cell, wherein the methylation level of the ID4 gene promoter in the cell, if lower than a control methylation level, indicates that the test compound is a candidate for treating breast cancer.   
     
     
         4 . The method of  claim 3 , wherein the cell is an early stage primary tumor cell. 
     
     
         5 . A method of treating metastatic cancer, comprising:
 obtaining a biological sample from a human subject having cancer or at risk for developing cancer;   determining the methylation level of an ID4 gene promoter in the sample;   identifying the subject as being suffering from or at risk for developing metastasis if the methylation level of the ID4 gene promoter in the sample is higher than a control methylation level; and   administering to the subject an effective amount of a compound that decreases the methylation level of the ID4 gene promoter in the subject.   
     
     
         6 . A method of treating breast cancer, comprising:
 identifying a subject suffering from or at risk for developing breast cancer, wherein the methylation level of an ID4 gene promoter in the subject is higher than a control methylation value; and   administering to the subject an effective amount of a compound that decreases the methylation level of the ID4 gene promoter, increases the expression level of the ID4 gene, or a combination thereof in the subject.   
     
     
         7 . The method of  claim 6 , wherein the subject is a human.