Role of Vitamin D Receptor and PI3k Genes in Breast Cancer
Creators: name: University Of California Office Of The President
Publisher: name: University of California Office of the President
publisherIdentifier: https://ror.org/00dmfq477
publisherIdentifierScheme: ROR
Year: 2024

description: Any medicine that would reduce breast cancer risk, arrest tumor growth and spreading would be highly desirable. Vitamin D displays all of these features, however application has not been feasible, because the high doses required would raise calcium levels in the blood stream to lethal levels. In addition, sporadically researchers have shown cancer stimulatory effects of Vitamin D. Clearly a lack of knowledge hinders the development of Vitamin D-like drugs that target tumor growth but not calcium levels. 
 
 
 
 Breast tumor cells sense Vitamin D with a specific Vitamin D receptor (VDR). Unexpectedly, we found that in certain breast and lung cancers Vitamin D receptor gene expression is correlated with the expression of a second gene, PI3k. The PI3k gene is a central player amongst known cancer genes and detailed information is available about the mechanisms used by this gene to regulate cell and tumor growth. Therefore, further determination of the relationship between the two genes will explain many of the effects of Vitamin D during breast cancer progression, which is important for future drug design.
 
 
 
 The main questions of this research in non-technical terms are:
 
 -Are the Vitamin D receptor gene and the central gene in cell growth regulation (PI3k) co-expressed in all types of breast cancer or only in certain types or classes?
 -Is there a cancer gene in the human chromosome that regulates the coordinate expression of the two genes? Is this a new cancer gene or a new function of a known cancer gene that can be specifically targeted for anti-cancer drug design?
 -Can the growth regulatory and anti-cancer effects of Vitamin D be explained by a direct interaction of the Vitamin D receptor and the cell growth regulator PI3k?
 
 We will attempt to answer the questions posed above by doing the following:
 
 -We will measure the expression of the Vitamin D receptor gene and the central gene in cell growth regulation (PI3k) in 4 additional types of breast cancer; lobular, tubular, metastatic and DCIS. (Advocates are involved in the decision to make frozen samples available for this research project)
 -We will systematically screen the complete chromosome for a regulatory gene using DNA chip technology. Virtually all genes in the human chromosome are represented on the DNA chips.
 -We will investigate, in breast cancer cells, the complex formation found by other researchers in leukemia, between the Vitamin D receptor and the central gene in cell growth (PI3k). This complex formation only happened in the presence of Vitamin D.
 
 Clinical trials using Vitamin D or Vitamin D-like drugs alone or in combination with chemotherapy or other drugs have already been promising in breast cancer. Also, the known cancer genes regulated by PI3k are targets for anti-cancer drug design. A better understanding of an interaction between the two genes will enhance future therapeutic developments. In addition, the relation between the expression of the two genes may be used as important prognostic and diagnostic factors depending on the commonality of the correlation between the two genes.