Two-pore channels as regulators of proliferation in cancer

Abstract

The present invention relates to the discovery that two pore K + channel (2PK) gene expression is increased in tumors and tumor cell lines, especially prostate tumor cells. The present invention encompasses methods for disease diagnosis, drug screening and the treatment of cancer.

1 . A method for identifying a compound that activates TREK-1 activity comprising (i) contacting a cell expressing TREK-1 with a test compound and measuring the level of TREK-1 activity; (ii) in a separate experiment, contacting a cell expressing TREK-1 protein with a vehicle control and measuring the level of TREK-1 activity where the conditions are essentially the same as in part (i), and then (iii) comparing the level of TREK-1 activity measured in part (i) with the level of TREK-1 activity measured in part (ii), wherein an increased level of TREK-1 activity measured in part (i) compared to the level measured in part (ii) indicates that the test compound is a TREK-1 activator. 
     
     
         2 . A method for identifying a compound that inhibits TREK-1 activity comprising (i) contacting a cell expressing TREK-1 protein with a test compound and measuring the level of TREK-1 activity, (ii) in a separate experiment, contacting a cell expressing TREK-1 protein with a vehicle control and measuring the level of TREK-1 activity, where the conditions are essentially the same as in part (i) and then (iii) comparing the level of TREK-1 activity measured in part (i) with the level of TREK-1 activity measured in part (ii), wherein a decreased level of TREK-1 activity in part (i) compared to the level measured in part (ii) indicates that the test compound is a TREK-1 inhibitor. 
     
     
         3 . A method for identifying a compound that inhibits proliferation of cells expressing TREK-1 activity comprising (i) contacting a cell expressing TREK-1 protein with a test compound and measuring the level of cell proliferation, (ii) in a separate experiment, contacting a cell expressing TREK-1 protein with a vehicle control and measuring the level of cell proliferation, where the conditions are essentially the same as in part (i) and then (iii) comparing the level of cell proliferation measured in part (i) with the level of cell proliferation measured in part (ii), wherein a decreased level of cell proliferation measured in part (i) compared to the level measured in part (ii) indicates that the test compound is an inhibitor of cell proliferation. 
     
     
         4 . A method for diagnosis and/or prognosis of cancer in a subject comprising: (a) detecting the level of TREK-1 expression in a sample derived from a subject; and (b) comparing the level of TREK-1 expression detected in the subject's sample to the level of TREK-1 expression detected in a control sample, wherein an increase in the level of TREK-1 expression detected in the subject's sample as compared to a control sample is an indicator of a subject with cancer or progression toward cancer. 
     
     
         5 . The method of  claim 1  wherein the level of TREK-1 RNA expression is measured. 
     
     
         6 . The method of  claim 1  wherein the level of TREK-1 protein expression is measured. 
     
     
         7 . The method of  claim 3  wherein the level of TREK-1 protein expression is measured using an immunoassay. 
     
     
         8 . The method of  claim 1  wherein an increase in the level of TREK-1 expression detected in the subject's sample as compared to a control sample is an indicator of a subject with cancer or progression toward cancer. 
     
     
         9 . A method for monitoring the therapeutic effect of a cancer treatment on a subject comprising: measuring at time intervals before, during, or after cancer treatment the amount of a TREK-1 expression wherein a change or absence of change in the amount of the TREK-1 gene expression is correlated with the effect of the cancer treatment on the subject. 
     
     
         10 . The method of  claim 5  wherein a decrease in the level of TREK-1 expression during or after cancer treatment as compared to the level of TREK-1 expression before treatment is correlated with a positive response to the treatment. 
     
     
         11 . The method of  claim 6  wherein the level of TREK-1 RNA expression is measured. 
     
     
         12 . The method of  claim 6  wherein the level of TREK-1 protein expression is measured 
     
     
         13 . The method of  claim 9  wherein the level of TREK-1 protein expression is measured using an immunoassay.