New Study Reaveals How Prostate Cancer Becomes Incurable
The Ohio State University Comprehensive Cancer Center and the Dana-Farber Cancer Institute have conducted recent studies, which reveal how hormone independent late state prostate cancer tumors are able to grow independently without the hormones. When this happens, it means that the prostate cancer has reached the advanced stage and is not able to be cured.
The study was published in the July 2009 issue of the Cell and focuses upon the androgen receptors, the molecules present in the nucleus of prostate gland cells and some other tissues. Androgens, the male sex hormones, get bound with these androgen receptors and ultimately, activate the genes which control the growth of cells.
According to the research, in the prostate cancer that does not need androgens to grow, the androgen receptors get reprogrammed for regulating the group of genes that are involved in a later, different phase of division of cells. This triggers the growth of cells rapidly. It is further shown that modifying the chief component of chromosome lead to this kind of reprogramming.
Qianben Wang, the assistant professor of cellular and molecular biochemistry and one of the researchers in the Ohio State University Comprehensive Cancer Center- James Cancer Hospital and the Solove Research Institute said that although some of the prostate cancers in the advanced stage do not need androgen hormones for their tumor growth, but they require the androgen receptors.
The study reveals how androgen receptors are important for development of prostate cancer that has become hormone independent. It studies how these androgens become active and what genes are regulated by them to support the growth of the tumor. After these findings, prostate cancer can be understood in a better way and new therapies can be identified to get rid of this cancer and new treatments can be developed to cure the disease even at an advanced stage.
Prostate cancer is one of the most commonly diagnosed cancers in men. In the year 2009, more than 192,250 cases of prostate cancer have been expected in US alone and around 27, 360 deaths are anticipated due to the disease.
The study has been conducted by Wang, Dr. Myles Brown, and some colleagues. Brown is working as a professor medicine at the Harvard Medical School and the Dana-Farber Cancer Institute. They used the cell lines of both hormone dependent and independent prostate cancer, data from gene expression and tissues from the human tumors. The study showed that in the hormone-dependent prostate cancer, an earlier phase of the cell cycle is regulated by the androgen receptors. In hormone-independent disease, the receptors receive a reprogramming for selectively regulating the genes that are involved in the division of cells, which is known as the mitotic phase of the cell cycle.
UBE2C, a gene, stood out among the other genes and the increased expression of this gene was in co-relation with the progression to the phase in which the prostate cancer becomes hormone-independent. In addition to that, epigenetic change is a chemical change in the histone protein that is associated with the gene enables the androgen receptors be become bound with the gene and activate it in the hormone-independent cancer.
Finally, it was shown that the over-expression of these genes is essential for the cancer cells responsible for hormone-independent prostate cancer. Wang says that the UBE2C gene also gets over-expressed in others types of cancer including breast, bladder, lung, ovary, esophageal and thyroid. This suggests that the findings revealed from the study can have a much wider application. Funding for the study is supported by the National Cancer Institute and the Department of Defense.