ABSTRACT

Breast cancer is one of the most common cancer types among women in the world. Breast cells can be divided uncontrollably in either lobules or ducts. Breast cancer can be in situ or invasive, depending on its type. Cholesterol homeostasis is an important parameter for cancer progression. Mevalonate pathway, also known as the de novo cholesterol synthesis pathway, is the essential part for cholesterol synthesis. In this pathway, important intermediates are produced for production of cholesterol. In the first step of the pathway, 3-hydroxy-3- methylglutaryl coenzyme A, known as HMG-CoA, is converted to mevalonate by the ratelimiting enzyme HMGCR and the final product is farnesyl pyrophosphate called FPP, which is the building block of cholesterol. In this study, we aimed to determine the expression level of the HMGCR gene, which encodes 3-hydroxy-3-methylglutaryl-coenzyme A reductase enzyme, in different breast cancer cell lines: MDA-MB 231, MDA-MB 435, MDA-MB 453, UACC 2080, MCF-7, HCC 1938 by real-time PCR. As a result, we found that the MCF7 cell line has the lowest level of HMGCR mRNA, and the MDA-MB-453 cell line has the highest level of HMGCR mRNA. Differences in expression levels may be due to hormone receptors. Furthermore, other triple negative cell lines showed different expression levels among themselves, although they expressed more HMGCR than MCF-7. The reason for this was thought to be related to the location of cancer formation or the age of the patient.