researchers found that a compound found in broccoli, sulforaphane, killed breast CSCs and inhibited new tumors. Another interesting finding was that curcumin, a component of the Indian spice turmeric, decreased the number of breast CSCs that were able to grow in the laboratory. With the help of an international research team, scientists determined the transition between being in the epithelial and mesenchymal states (development states of the breast cancer cell) endows breast CSCs with the capacity for tissue invasion, dissemination, and metastasis.
These research findings provide significant avenues to exploit the use of stem cells as a treatment for breast cancer. One pathway is the use of monoclonal antibodies for the specific targeting of breast CSCs. Another pathway is to exploit the tropism between MSCs and breast CSCs. MSCs could be genetically modified and used to deliver drugs specifically to tumor cells. Studies performed in the laboratory have suggested the use of genetically modified MSCs to deliver therapy to breast cancer tumors. However, the mechanism has not been fully defined. To exploit these pathways, an in-depth understanding of signaling between normal cells and breast CSCs is required to minimize damage to healthy cells.
Use of Stem Cells in Breast Cancer Treatment
As noted, MSCs would be a good candidate to use as a modified stem cell to deliver breast CSC-specific chemotherapy. Lentiviral vectors have been used to modify MSCs without modifying cell-surface markers.
In addition to their ease of modification, MSCs are attracted to tissue injury by specific cytokines. MSCs play a role in tissue repair as part of their normal role in the body. MSCs migrate to tumors (since they damage the surrounding tissue) and could be exploited as drug transporters to specific tumor sites.
To date, stem cells have been used in clinical trials as supportive therapy to replenish blood cell development or to ameliorate other side effects of treatment for breast cancer.
Conclusion
During 2012, approximately 522,000 women died of breast cancer. Although the treatment of breast cancer has improved, breast cancer remains a leading cause of death. Stem cell research has elucidated the role of breast CSCs in the initiation of tumors, the development of growth, the dissemination of cancer cells, and the resistance to treatment. Stem cells have the potential to be use not only in the treatment of breast cancer but in its prevention and in its diagnoses.
Kecia Brown
Independent Scholar
See Also: Cancer Stem Cells: Overview; Mesenchymal Stem Cells; Stem Cell Niche.
Further Readings
Goldthwaite, Charles A. “Are Stem Cells Involved in Cancer?” National Institutes of Health. http://stemcells.nih.gov/info/Regenerative_Medicine/pages/2006chapter9.aspx (Accessed September 2014).
Kasai, Tomonari, et al. “Cancer Stem Cells Converted From Pluripotent Stem Cells and the Cancerous Niche.” Journal of Stem Cells & Regenerative Medicine, v.10/1 (2014).
Madjd, Thomas A. “Application of Stem Cells in Targeted Therapy of Breast Cancer: A Systematic Review.” Asian Pacific Journal of Cancer Prevention, v.441 (2006).
University of Michigan Health System. “New Breast Cancer Stem Cell Findings Explain How Cancer Spreads.” ScienceDaily (January 14, 2014). http:/www.sciencedaily.com/releases/2014/01/140114102503.htm (Accessed September 2014).
Breast: Development and Regeneration Potential
Breast: Development and Regeneration Potential
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Breast: Development and Regeneration Potential
Breast cancer is the most recurrent form of cancer among American women. The American Cancer Society estimates that about 12% of women in the United States will develop invasive breast cancer during their lifetime. Despite the fact that the current five-year survival rate is at about 90% in the United States, and in spite of the existence of advanced technologies for screening and treatment, 40% of women still undergo a mastectomy as part of their treatment. Currently, breast reconstruction is an option proposed to female patients to help them overcome any potential psychological, physical, and emotional strain caused by breast cancer management. Rates of breast reconstruction in the United States revolve around 25%.
Breast reconstruction may happen right after surgery, or at a later stage, through the use of implants, autologous tissue, or a combination of both. Standard methods of soft tissue reconstruction include autologous fat transplantation, autologous tissue flaps, and alloplastic (artificial) implants. All of these approaches present shortcomings, such as the risk of surgery, donor-site morbidity, rejection of foreign bodies, and implant migration. Research suggests that stem cells, cell-based therapies, and tissue engineering could be important in breast reconstruction.
Embryonic and adult stem cells are capable of unlimited renewal through cell division while retaining their unspecialized features and plasticity, thus enabling them to differentiate into a variety of specific cell types. Pluripotent cells are capable of differentiating into the 216 specialized cells that make up the human body, while multipotent cells are able to give rise to a more restricted number of specialized daughter cells.
Stem cells can be collected from adult or embryonic tissues and can potentially be used for regenerative therapies. The benefit of such treatment could be extended in the future to breast cancer patients who would no longer need to undergo invasive breast reconstruction surgery, or to women with partial mastectomy who would no longer need procedures aimed at correcting defects caused by a previous reconstructive surgery.
Clinical Use of Adipose-Derived Stem Cells (ASCs) and Tissue Engineering in Breast Reconstruction
Adipose-derived stem cells (ASCs) are plentiful, readily available multipotent progenitor cells residing in adipose tissue. Their therapeutic potential in experimental clinical trials and preclinical studies has been well documented. Although recognized as potentially useful for breast reconstruction, a complete understanding of the underlying biology of adipose stem cells and their interaction with other cells and growth factors is still lacking. Additionally, fat grafting, or the transfer of fat from one place in the body to another for reconstructive or aesthetic purposes, is at times associated with complications such as oil cysts or risks of forming nodules. Supplementary clinical data should thus be evaluated to ensure whether lipofilling is unsafe or whether it increases a patient’s chances of developing cancer.
Among the many potential cell-based therapies, adipose-derived stem cells (ASCs), induced pluripotent stem cells (iPSCs), and embryonic stem cells (ESCs) are among the most promising treatment options. iPSCs and ESCs have generated considerable enthusiasm because they are pluripotent, but ESCs have ethical limitations. ASCs have the ability to differentiate into chondrocytes, adipocytes, myocytes, osteoblasts, and neurons, and furthermore demonstrate a great flexibility in adapting to specific conditions of differentiation, which is key in regenerative medicine.
Clinical Trials
Often,
