Diagnosing and treating hormone resistant cancers

1. A method of determining whether a cancer cell is sensitive to endocrine therapy comprising:

a) obtaining a population of cancer cells; and

b) determining the presence of binding of DBC-1 and Estrogen Receptor α (ERα), the presence of binding of DBC-1 and ERα as compared to a control indicating that the cancer cells are not sensitive to endocrine therapy.

2. A method of determining whether a subject with cancer is suitable for treatment with endocrine therapy comprising:

a) obtaining a biological sample comprising cancer cells from the subject; and

b) determining the presence of binding of DBC-1 and ERα, the presence of binding of DBC-1 and ERα as compared to a control indicating that the subject is not suitable for treatment with endocrine therapy.

3. The method of claim 2 , wherein the cancer cells are endometrial cancer cells, breast cancer cells, ovarian cancer cells or prostate cancer cells.

4. The method of claim 2 , wherein step b) is carried out using a polyclonal antibody that binds DBC-1 in the region of amino acids 475-923.

5. A method of determining a susceptibility to hormone resistant cancer in a subject comprising:

a) obtaining a biological sample comprising cancer cells from the subject; and

b) determining the presence of binding of DBC-1 and ER-α, wherein the presence of binding of DBC-1 and ER-α as compared to a control indicates that the subject is susceptible to hormone resistant cancer.

6. The method of claim 5 , wherein the subject has endometrial cancer, breast cancer, ovarian cancer or prostate cancer.

7. The method of claim 5 , wherein step b) is carried out using a polyclonal antibody that binds DBC-1 in the region of amino acids 475-923.