Breast Cancer

Breast Cancer

Breast cancer is a type of carcinoma that affects both men and women but is most common in women.  Cancer occurs when the cellular tissue lining the lobules that produce milk mutate or more commonly when the cells in the in the ducts that convey the milk to the nipples (Kamińska, Ciszewski, Łopacka-Szatan, Miotła, & Starosławska, 2015). This paper will describe some other risk factors that predispose one to get carcinoma of the breast with emphasis on the genetic mutation that takes place.

People with the following risk factors are more likely to develop breast cancer as compared to the others. First are people who have had mutations in one of the two recognized breast cancer genes which are BRCA-2 and BRCA-1. After the mutation, such people have a very high chance of developing breast cancer. The next groups of risk factors have to do with the reproductive hormones of the body. Women who undergo early menarche are at higher risk that their counterparts who have menarche later in life. Similarly, women who have late menopause are at increased danger of getting breast cancer than the women who have menopause earlier. Finally, carry in pregnancy to full term after the age of forty years enhances the likelihood of females developing breast cancer (Kamińska, Ciszewski, Łopacka-Szatan, Miotła, & Starosławska, 2015).

The final category of risk is related to the environmental factors. Exposure to radiations is one of the predisposing factors for breast cancer. People who have had extended periods of exposure to radiations are more likely to develop breast cancer that those individuals who haven’t (Kamińska, Ciszewski, Łopacka-Szatan, Miotła, & Starosławska, 2015). Excessive consumption of alcohol puts one at risk of developing breast cancer and finally smoking cigarettes puts people at risk of developing breast cancer.

Tumor suppressor genes are those whole genes loss of function leads to malignancy. The tumor suppressor genes negatively regulate the growth of cells and other cellular features that may influence the metastasis and invasive potential of cancerous cells. In the breast, cancer mutations occur in these genes causing them to lose their function (Zhu et al., 2015). The tumor suppressor genes affected in breast cancer include; TP53, BRCA1/2, RB1 and PTEN. Oncogenes, on the other hand, are genes that normally help cells to proliferate. When the oncogenes mutate, many copies of it made and the cells grow out of control. The oncogenes that are affected in breast cancer include the following: ErbB2, MYC, and PIK3CA (Zhu et al., 2015).

A vital difference between tumor suppressor genes and oncogenes is that tumor suppressor genes cause cancer when inactivated whereas the tumor oncogenes cause cancer when turned on or activated. Studies have also revealed that tumor suppressor genes have a higher frequency of mutation than the tumor oncogenes (Zhu et al., 2015). Other results from similar studies indicated that tumor suppressor genes had the same network characteristics despite having different mutation patterns. Furthermore, while mutation often occurred in somatic tissues and therefore could not be inherited, in tumor suppressor genes mutation could occur in somatic cells or germ cells thereby allowing for inheritance. Finally, while the oncogenes depicted only some tissue preference, the tumor suppressor genes showed strong tissue preference (Zhu et al., 2015).

In summary, this paper has briefly described breast cancer, its risk factor and the genes involved in its causation. Gene mutation, hormonal factor and environmental factor are some the predisposing factors that the paper has highlighted. The article has gone further to identify the primary tumor suppressor genes and the oncogenes affected in cancer of the breast.




Kamińska, M., Ciszewski, T., Łopacka-Szatan, K., Miotła, P., & Starosławska, E. (2015). Breast cancer risk factors. Menopausal Review3, 196-202.

Zhu, K., Liu, Q., Zhou, Y., Tao, C., Zhao, Z., Sun, J., & Xu, H. (2015). Oncogenes and tumor suppressor genes: comparative genomics and network perspectives. BMC Genomics16(Suppl 7), S8.