Written by Hafsah Ganatra and Edited by Gauri Ajith
As scientific advancements attempt to understand the world’s diseases and epidemics, research remains the great domain of innovative development and scientific progress. The focus of many of these projects is cancer, currently the nation’s second leading cause of death with a predicted 1,735,350 new diagnoses in 2018 alone [1]. Of the 878,980 new cases predicted for women in 2018, 30% are projected to be diagnoses of breast cancer [1]. Current options for breast cancer remedies emphasize strategized treatment plans focused on halting cancer development and advancement through methods such as gene therapy (a method of replacing mutated or improper genes with healthy ones), chemotherapy, medication, surgery, and radiation [2]. Recently, however, researchers have made progress by discovering new information about the molecular pathway responsible for the progression of breast cancer [3]. This new finding could be essential for developing new treatment options for breast cancer patients.
Many biological pathways that lead to cancer can be attributed to mutations of genes within the DNA sequence itself. These mutations can alter various properties of certain genes, including levels of expression and protein concentrations. Oncogenes, or mutated genes responsible for the development of cells into tumor cells, are a prime focus of study, especially among molecular biologists looking for insights into cancer pathways. These pathways refer to the biological mechanisms that can be mutated to result in the formation of tumor cells. By studying and researching significant processes within these cancer pathways, scientists are able to discover which aspects of the biological mechanisms can be altered to inhibit cancer growth or formation [2].
A recent discovery was that SETDB1, an oncogene involved in the pathway of many cancers, could be a contributing factor to breast cancer progression [3]. This study collected forty-five samples of human breast tissue taken from breast cancer surgeries and tested the tissues for expression of the SETDB1 gene. A few of the assays, or tests, done included both lab-based testing through a Western blot analysis of protein fragments and a live animal model [3]. Western blotting uses protein extraction to separate and identify different proteins by size, weight or antibody type [4]. This assay was done to compare levels of expression for the SETDB1 protein in extracted human breast cancer tissue. Another method used to test the gene pathway was an in vivo, or living, animal model. This was done by injecting mice beneath the skin with plasmids, or small circular DNA fragments, containing mutated SETDB1 genes and tumor grafts before testing the tumor size and progression in ten-day periods. These results were compared with that of mice injected with tumor grafts and gene suppressors that limited SETDB1 gene expression [3].
After collecting and processing the data, the researchers discovered that the in vivo results indicated that suppression of the oncogene could lead to a decrease in tumor growth. The mice that were tested were found to have significantly smaller tumors when the gene suppressors were also applied. Meanwhile, the study also found that there were higher levels of SETDB1 protein in human breast cancer tissue through the Western blot analysis. Taking these results together, this study indicates that suppression of the SETDB1 gene can help halt the progression of breast cancer [3]. Such new findings can be used to genetically modify the SETDB1 gene pathway, thus further enhancing current breast cancer therapies and giving new hope for advancements in breast cancer treatment.
References:
- Siegel, R.L., Miller, K.D., and Jemal, A. (2018). Cancer Statistics, 2018. CA: A Cancer Journal for Clinicians, 68:7-30. https://onlinelibrary.wiley.com/doi/epdf/10.3322/caac.21442
- Sharma, G. N., Dave, R., Sanadya, J., Sharma, P., & Sharma, K. K. (2010). Various types and management of breast cancer: an overview. Journal of Advanced Pharmaceutical Technology & Research, 1:109-26. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3255438/
- Wu, M., Fan, B., Guo, Q., Li, Y., Chen, R., Lv, N., Diao, Y., Luo, Y. (2018). Knockdown of SETDB1 inhibits breast cancer progression by miR-381-3p-related regulation. Biological Research, 51:39-39. https://biolres.biomedcentral.com/articles/10.1186/s40659-018-0189-0
- Mahmood, T., & Yang, P. C. (2012). Western blot: technique, theory, and trouble shooting. North American Journal of Medical Sciences, 4:429-34. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3456489/