A method of detecting prostate tumorigenesis in a subject, the method including the steps of (a) obtaining a sample from the prostate of the human subject, (b) detecting quantitatively or semi-quantitatively in the sample a level of expression for PKC-ι and (c) comparing the expression level in (b) to a level of expression in a normal control, wherein overexpression of PKC-ι, with respect to the control, indicates the presence of prostate cancer in the subject. The present invention is based upon the discovery that PKC-ι levels are elevated during prostate tumorigenesis. Furthermore, the proliferation rate of the tumor correlates with the level of PKC-ι. The invention also provides methods of treating prostate cancer by administering to the subject a compound that inhibits the expression of PKC-ι. The compound can be a small interfering RNA (siRNA) molecule.
