Many, if not all, of us know someone who is battling cancer or has battled this type of cancer. According to the National Cancer Institute, one in eight women who live to be 80 years old will develop breast cancer. It is the second most commonly diagnosed cancer among women, just after skin cancer. While most breast cancer diagnoses are for women, a number of them are diagnosed in men. The breast is composed of glands that make breast milk known as lobules, small tubes that carry the milk from the lobules to the nipples known as ducts, tissue, and blood and lymph vessels. The two areas that are most likely to develop cancerous cells are the ducts and glands, but in rarer cases it can develop in the other areas. Breast cancer may also develop from lymph nodes that surround the breast, like those of the underarm.
The progression of cancer is the result from a series of changes, which include the inactivation of tumor suppressor genes and the activation of oncogenes. There are different oncogenes that are discussed in the Molecular basis of breast cancer that are linked to breast tumor progression. These include p53, BCL-2, Bag-1, P27, Skp2, HER-2, and the estrogen receptors (ER). P53 is a tumor suppressor gene and is involved in the regulation of normal cell growth and division. Disruption of the function of p53 results in continued survival allowing continued growth of damaged cells. Bcl-2 is a family of genes that can either be pro-survival or pro-apoptotic (death of cells). A balance between these different types controls the development and function of normal breasts. Bag-1 is a Bcl-2 interacting anti-apoptotic protein. It also binds hormone receptors and inhibits hormone induced cell death. Bag-1 plays a key role in the oncogenesis and progression of breast cancer. Lowered expression of p27 is linked to overall survival and shorter time to progression. Loss of p27 is linked to the change of cells from normal to premalignant to malignant. S-phase kinase-association protein, or Skp2, is needed for degradation of p27. HER-2 is a promising tumor marker. Evidence shows that over-expression of HER-2 is involved in the progression of breast cancer. Another molecular marker association with breast cancer is the estrogen receptor (ER), which plays a key role in the rapid increase of responsive cells.
References:
http://www.cancercenter.com/breast-cancer/?source=GGLPS01&channel=paid+search&invsrc=Non_Branded_Paid_Search_Google_Cancer_Search&utm_device=c&utm_budget=Corporate&utm_site=GOOGLE&utm_campaign=Non+Brand%3ECancer+Type%3A+Breast&utm_adgroup=Breast+Cancer%3EGeneral%3EExact&utm_term=breast+cancer&utm_matchtype=e&k_clickid=9f30dc28-88bc-4c7f-9ebf-59cb923353f4&k_profid=422&k_kwid=3852244
http://smj.org.sa/index.php/smj/article/viewFile/3481/1255
