Background
For men in the U.S. prostate cancer is the most commonly diagnosed cancer, and the second leading cause of cancer-related death.  Prostasin is a serine protease predominantly expressed in normal prostate epithelial cells and present at high levels in normal human semen.  Current research shows that both prostasin protein and mRNA were found to be expressed in normal human prostate epithelial cells and a non-invasive human prostate cancer cell line, LNCaP, but neither was found in invasive human prostate cancer cell lines DU-145 and PC-3. Transfection of DU-145 and PC-3 cells with a full-length human prostasin cDNA restored prostasin expression and reduced the in vitro invasiveness by 68% and 42%, respectively. Prostasin has also been shown to be absent in highly invasive and metastatic breast carcinoma cell lines compared to non invasive or nonmetastatic breast carcinoma lines. The evidence thus qualifies prostasin as an invasion suppressor, which can be used as a marker for diagnosis of invasiveness of prostate and breast cancers, or as a therapeutic agent to treat invasive prostate and breast cancers.

Application
This invention relates to prostasin and its use in the diagnosis and treatment of prostate and breast cancers.

Invention
The current invention confers a method for determining whether human prostate or breast carcinomas are non invasive, comprising sampling human breast or prostate carcinomas and determining whether the prostasin gene promoter DNA is methylated at bp 1,156/-266, where the absence of methylation indicates a non-invasive carcinoma.

Advantages
•    A method for determining which cancer patients do not require chemotherapeutic treatment, comprising of taking a biopsy of a prostate or breast tumor, and determining the non-invasiveness of the carcinoma tissue based on the absence of methylation of the prostasin gene promoter DNA.
•    The ability to precisely predict upon early pathological examination of the tumor, which group of patients will have truly organ-confined disease versus which group will have invasive prostate cancer.
•    Prostasin could be delivered via a gene delivery vector to the human carcinoma reducing invasiveness of the human carcinoma.

Lead Inventor
Karl Chai, Ph.D.

Selected References
Chen LM, Zhang X, Chai KX.. Regulation of prostasin expression and function in the prostate. Prostate 2004; 59(1): 1-12.

Chen M, Fu YY, Lin CY, Chen LM, Chai KX. Prostasin induces protease-dependent and independent molecular changes in the human prostate carcinoma cell line PC-3. Biochim Biophys Acta 2007; 1773(7): 1133-40.

Chen LM, Chai KX.. Prostasin serine protease inhibits breast cancer invasiveness and is transcriptionally regulated by promoter DNA methylation. Int J Cancer 2002; 97(3): 323-9.

Contact
Attn: Svetlana Shtrom, Ph.D., MBA
University of Central Florida
Office of Research and Commercialization
12201 Research Parkway, Suite 501
Orlando, Fl 32826-3246
Phone: 407.823.5150
Fax: 407.823.3299
sshtrom@mail.ucf.edu

UCF ID# 6354, 6358, 6359/6652