Breast Cancer A Complex And Heterogeneous Disease Caused...

Breast cancer is a complex and heterogeneous disease caused by both genetic and non-genetic risk factors. These factors include, mutations in breast cancer-associated genes 1 and 2 (BRCA1 and BRCA2) [1]; loss or aberrant expression of the estrogen receptor (ER) [2]; human epidermal growth factor receptor (HER2) overexpression [3] ; lack of ER, progesterone receptor (PR), and epidermal growth factor receptor (EGFR) expression[4] ; high levels of receptor for the insulin-like growth factor receptor 1 (IGF-1R[5]; and expression of microRNA (miRNA) [6]. In addition to genetic alterations (gene amplifications, deletions, point mutations, and chromosome rearrangements), epigenetic changes (methylation and/or acetylation) of the genome play an important role in breast carcinogenesis. For example, methylation of RASSF1A, BRCA1, and estrogen receptor ÃŽ ± (ERÃŽ ±) is associated with breast tumorigenesis and metastasis [7]. The inactivation of tumor suppressor proteins that lead to tumor cell growth and survival are another mechanism of breast cancer development [8]. These genes are inactivated by a variety of mechanisms, including chromosomal deletions, intragenic mutations, proteolysis, and loss of epigenetic modifications [9]. The best-characterized tumor suppressor protein is p53. In breast cancer, p53 mutation or downregulation is associated with an adverse prognosis [10]. Other tumor suppressor proteins in breast cancer include PTEN [11], p16[12], the retinoblastoma gene[13], andShow MoreRelatedEssay about Breast Cancer836 Words   |  4 PagesBreast cancer is one of the most widespread cancers among women worldwide. In the US, it is the most common, and the leading cause of cancer related deaths among women between 45 – 64 years of age (Clegg et al., 2002; Ward et al., 2008). Early detection and improved treatment procedures have resulted in gradual decline in the number of deaths caused by the disease since 1990. Nevertheless, in 2009, the estimated de ath toll for the disease was 40,170 (American Cancer Society, 2009). The gravityRead MoreThe Biology Of A Cell Mass1676 Words   |  7 PagesAbstract Genetic instability and the accumulation of several molecular alterations are the cause of cancers through the development of a proliferative cell mass. However, it is restricted to the current prognostic and diagnostic classifications since there is no reflection of the entire tumor clinical heterogeneity. Therefore, they are not sufficient in making predictions for the adequate treatment of patients. The chances of survival for the patients suffering from cancer normally depends on theRead MoreNeoplasia10526 Words   |  43 PagesIbom State, Nigeria. Neoplasia means the process of new growth whilst Neoplasm means a new growth. Sometimes, the parenchyma cells stimulate the formation of an abundant collagenous stroma, referred to as desmoplasia. Some tumours e.g. some cancers of breast are stony hard or scirrhous. Sarcomas have little connective tissue stroma and so are fleshy. Pseudo tumours: i) An ectopic rest of normal tissue is sometimes called a choristoma e.g a rest of adrenal cells under the kidney capsule or a pancreaticRead MoreSexually Transmitted Diseases35655 Words   |  143 Pagesprokaryotes 130 Structures and functions 133-137 Microbes 148-150 Onion and cheek cells 150-151 Ecological study 154 Seed structure and germination 155-157 Reproduction in plants 158-165 Sexually transmitted diseases 166-176 Birth Control and contraceptives 177-185 Effects on population growth 186-187 Drug and drug abuse 188-191 Man’s impact on the environment 192-199 Reproduction in man 200-201 References 202 Introduction Read More_x000C_Introduction to Statistics and Data Analysis355457 Words   |  1422 Pagespressure, leading researchers to conclude that the use of therapeutic dogs is beneï ¬ cial in the treatment of heart patients. (San Luis Obispo Tribune, November 16, 2005) Late in 2005, those eligible for Medicare had to decide which, if any, of the many complex new prescription medication plans was right for them. To assist with this decision, a program called PlanFinder that compares available options was made available online. But are seniors online? Based on a survey conducted by the Los Angeles Times