Tissue By Immunohistochemistry On A Breast Tissue Microarray

This paper aims to provide the gaps in our understanding of breast cancer by examining the functions and to enhance our ability to distinguish the anatomy of female human breast. The author also attempts a better understanding of some of the different types of human breast cancer namely: ductal carcinoma in situ, lobular carcinoma in situ, invasive ductal carcinoma and invasive lobular carcinoma. It is hoped that this paper will inform those who do not have the understanding and knowledge about the risk factors, diagnosis, treatments and preventions of the breast cancer.

The aim of this report is to provide primary evidence which supports and explains the reasons why Herceptin is used in the treatment of HER2+ cancers.

As the cells change, it begins to divide rapidly causing a tumor to form. The term “breast cancer” refers to a malignant tumor that has developed from cells in the breast. Breast cancer can begin in different areas of the breast, or in some cases, the tissues in between. There are many different types of breast cancer, including non-invasive, invasive, recurrent, metastatic breast cancer, as well as the intrinsic or molecular subtypes of breast cancer. Human epidermal growth factor receptor 2 (HER2) is overexpressed in around 20-30% of breast cancer tumors. It is associated with a more aggressive disease, higher recurrence rate, and increased mortality.

Breast cancer constitutes the second most prevalent cancer most common among women of the world with an estimated 1.62 million reported cases in 2012 which constitutes 25% of all cancer cases and ranks fifth among mortality due to cancer (Ferlay et al., 2015). In the United States, according to American Cancer Society an

Oncogenes were discovered in the 1960s, when it was discovered that some animal cancers such as lymphomas were caused by viruses. Some of these viruses were notable due to the simplicity of their RNA genome. These viruses only had three distinct transcription units, involved in the replication of the virus (coat proteins and reverse transcriptase etc.), and an extra gene. This was an oncogene. When oncogenes are properly functioning they are termed proto-oncogenes (Todd R, 1999). Their normal function is to control cell proliferation. These function in growth signalling pathways, and conversely to tumour suppressing cells are activated through a gain in function rather than a loss of it. This occurs in two ways, by producing more of a product, or producing a subtly different product, as a result of a mutation similar to tumour suppressor genes (Croce, 2008). Oncogenes play a particularly strong role in the development of breast cancers. Often the normal ERBB2 and other related genes are amplified in late stage neuroblastomas and rhabdomyosarcomas. ERBB2 encodes HER2 which is a member of the epidermal growth factor

In this research paper, the experimental design was based around the relationship to CCND1 to breast cancer. CCND1 is present during the G1 phase of the mitosis cell cycle. Which occurs right before the S phase. If the CCND1 has a malfunction then the rest of the cell cycle will not finish off correctly into normal functioning cells. The research paper also noted that tumor heterogeneity is a critical issue and there is a hard time treating the tumors because it rejects most of the cell therapy treatments.

In vitro: Dacomitinib could reduce the phosphorylation of EGFR, HER2, and HER4 in various sensitive cancer cell lines through a combined G0–G1 arrest and an induction of apoptosis. In addition, dacomitinib inhibited growth in several HER2-amplified lines with resistance to trastuzumab. Moreover, dacomitinib

Diagnosis of cancer is not only the most important aspect in the overall management of the cancer patient, but it is also a very comprehensive and challenging task. It has been established beyond doubt that earlier the commencement of the treatment, better is the outcome; this is true for all diseases and more so for cancer. Research and studies have validated that the probability of survival for a time period of five years in a patient of breast cancer stage I is 90%–95%. However, this probability in case of patients in Sstage IV is found to be a mere 15%. This indicates not only the huge difference in the survival of patients according to their different stages of the disease, but also lays emphasis on the need for an early

Around 25-30% of the total breast cancer patients are diagnosed with HER2 gene amplification (Vogel, Charles L., et al, 2002). Patients with HER2 gene overexpression also produces a higher level of protein therefore, the patients with this condition are susceptible to decreased disease free and shorter overall survival rate(Vogel, Charles L., et al, 2002). The non-targeted cytotoxic chemotherapy has been used as a standard treatment of this condition. However, there are several side effects for these non-targeted therapies; such as vomiting, nausea, headache, fatigue, diarrhea, dizziness, anemia, thrombocytopenia, leukemia, anxiety, depression, anorexia and so on(O 'Shaughnessy, Joyce, et al, 2011). Therefore, a lot of patients are unable to use cytotoxic chemotherapy as a standard treatment. It is necessary to have a safe treatment that can serve the unmet purpose of these patients.

There are different types of breast cancer that could be used in planning treatment and new therapies. Authors of Mayo Clinic’s Breast Cancer page have written, “Your cancer's stage helps determine your prognosis and the best treatment options.” Therefore, many studies separate breast cancer into four molecular subtypes (“Molecular Subtypes”). Those subtypes would

Many breast cancers are sensitive to the hormone estrogen. Thus estrogen leads to development of breast cancer tumor

“Breast cancer is staged using the American Joint Committee on Cancer and the International Union for Cancer Control classification system for tumor, nodes, and metastases (TNM)” (Esserman, 2013).

Cancer is the uncontrollable division and growth of abnormal cells resulting in formation of an aggressive tumour. In some forms of Breast cancer, the cells proliferate uncontrollably due to over-expression of the protein HER2 (Human Epidermal Growth Factor Receptor 2); a receptor embedded within the membrane of cells, allowing for the transfer of signals outside to inside the cell. Trastuzumab is a monoclonal antibody administered through intravenous infusion, to be taken on its own or in combination with one or more chemotherapy regimens. It reduces risk of the cancer reoccurring or spreading by inhibiting the effects of HER2, and enhancing the body’s immune system.

According to the American Cancer Society, Each year, more than 200,000 women are diagnosed with breast cancer; furthermore Twelve percent of all women will contract the disease, and 3.5% of them will die from breast cancer (American Cancer Society, 2005). There are risk factors that may lead to breast cancer. There are 4 stages of breast cancer and several treatments, although treatments vary from types and stages of breast cancer. Breast cancer is the leading cause of death among women who are 40 to 55 years old (Breast Cancer, 2009).Cancer occurs when cells divide uncontrollably. It changes from a normal cell to cancerous cells that require gene alterations. Therefore the altered genes and the uncontrolled growth may lead to tumors.

It is crucial to illustrate that healthy cells in breast tissues tend to express low levels of aromatase transcriptions from exon 1.4. Once the cells in the breast turn to become carcinogenesis, the use of exon 1.4 is halted while exon 1.2 is used in the aromatase and