may also suppress the body’s natural response to reject newly transplanted skin grafts. Despite the promise associated with MSC treatment for wound healing, to date only limited clinical studies have been conducted. Clinical studies using MSCs are typically evaluated for accelerated wound closure, improved tissue strength, prevention of chronic ulceration, and improved visual appearance, with varied results depending on the type of study. Clinical research using MSCs for dermal wound healing has been limited by the lack of a scalable cell sourcing platform and a predictable regulatory framework.
A variety of biotech and pharmaceutical companies are focusing on stem cell–based research to provide therapeutic treatments for burn injury and a host of other skin-related diseases. With the regenerative capabilities stem cells naturally possess, therapeutic advances are expected to reduce healing time, scarring, and risk of infection for burn victims. With the number of alternatives currently available and the immense progress being made in this area, it is feasible that one day, split thickness skin grafting will be a thing of the past.
Tara Henriksen
CASE Forensics
See Also: Adult Stem Cells: Overview; Advanced Cell Technology; Clinical Trials Outside the United States; Mesenchymal Stem Cells; Skin Graft; Tissue Engineering (Scaffold).
Further Readings
Gaelle, L. and B. Cédric. “Medical Applications of Epidermal Stem Cells.” Stem Cell Research Community, StemBook (November 15, 2008). http://www.stembook.org (Accessed April 2014).
Galvan, S., U.S. Army Medical Department. “USAISR Burn Center Conducting Clinical Trials on New Skin Growth Procedure” (March 20, 2014). http://mrmc.amedd.army.mil/index.cfm? pageid=media_resources.articles.USAISR_conducting_clinical_trials_on_new_skin_growth_procedure (Accessed April 2014).
Gerlach, J. C., et al. “Autologous Skin Cell Spray-Transplantation for a Deep Dermal Burn Patient in an Ambulant Treatment Room Setting.” Burns, v.37 (2011).
Gravante, G., et al. “A Randomized Trial Comparing ReCell System of Epidermal Cells Delivery Versus Classic Skin Grafts for the Treatment of Deep Partial Thickness Burns.” Burns, v.33/8 (2007).
National Institutes of Health. “Stem Cell Information.” http://stemcells.nih.gov/info/pages/health.aspx (Accessed April 2014).
Schiffman, L. “Utah Study Shows Progress in Spray-On Stem Cell Healing Tech.” Popular Science (December 1, 2010). http://www.popsci.com/science/article/2010-12/utah-study-shows-progress-spray-stem-cell-healing-tech (Accessed April 2014).
Schurr, M. J., et al. “Phase I/II Clinical Evaluation of StrataGraft: A Consistent, Pathogen-Free Human Skin Substitute.” Journal of Trauma, v.66/3 (2009).
Stem Cell Network. “Wound Healing.” http://www.stemcellnetwork.ca/index.php?page=wound-healing&hl=eng (Accessed April 2014).
Clinical Trials, U.S.: Solid Tumors
Clinical Trials, U.S.: Solid Tumors
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Clinical Trials, U.S.: Solid Tumors
Cancer arises when a cell starts to divide in an abnormal, unregulated way and ends up forming a tumor. Solid tumors are defined as masses of abnormal tissue located in soft tissues or in organs devoid of fluid cysts. Harmless tumors do not contain cancerous cells and are therefore called benign, whereas dangerous tumors bear cancerous cells and are called malignant. Depending on where in the body they grow, tumors are called “solid” or “liquid.” More than 80 percent of all cancers are caused by solid tumors arising in a tissue, an organ, or a gland. Common sites for solid tumors are lungs, breasts, colon, prostate, brain, pancreas, skin, uterus, and liver.
With the growing incidence of cancer in the world and in the United States, there is an evident need to find better treatments for cancer tumors in general and for solid tumors in particular. Years of research and clinical trials in solid tumors have paved the way for researchers and scientists to test whether stem cell transplantation could benefit such conditions in a dramatic way. Clinical trials are constantly under way to test novel therapies that use stem cells in patients who do not respond to standard treatments.
The Nature of Solid Tumors
Solid tumors are further divided into sarcomas, lymphomas, and carcinomas, based on the cell types involved: sarcomas develop in cartilage, bone, muscle, fat, connective tissue, or blood vessels. Lymphomas are tumors of the lymphatic system. And carcinomas are tumors covering internal organs or growing in skin cells. Benign solid tumors can usually be removed and do not pose any long-term threat. Conversely, malignant tumors possess aggressive properties and can easily metastasize via blood or the lymphatic system, a harbinger of poor prognosis for the patient.
Why Do Solid Tumors Appear?
While it is true that cancer runs in families, only a minority of cases are caused by an inherited defective gene. Usually, the abnormal growth and treatment resistance of the majority of cancers are caused by irregularities in a patient’s gene sequence, or in gene regulation. Such deficiencies are usually acquired, rarely inherited.
Staging plays an important role in cancer diagnosis as it helps make therapeutic decisions based on historical data of specific outcomes after treatment. A combination of factors—size of tumor, number of lymph nodes, and whether metastases can be detected—provide details on the overall stage of the cancer, which is ranked from 0 to IV. The patient’s age and health status also influence the tumor prognosis.
Treatment
The standard of care sustaining the current treatment of solid tumors includes surgery, chemotherapy, and radiation. Surgery is known to be the treatment of choice for localized and treatable tumors. Chemotherapy, often combined with surgery and radiation, helps destroy cancer cells and extends a patient’s life. As for radiation, its main purpose is to shrink the tumor as much as possible prior to removal. A corollary outcome is the fact that administration of radiation prevents the recurrence of the tumor.
There is no doubt that surgery, chemotherapy, and radiation treatments offer valuable benefits to cancer patients; however, some of these therapies are debilitating, toxic, and occasionally lethal. Attempts to alleviate these side effects have led scientists to develop more targeted treatments, such as immunotherapy. In immunotherapy, tumor cells are exposed to powerful agents that suppress the tumor, or are tagged with specific beacons that trigger the immune system into targeting a tumor for elimination. In cell-based immunotherapies, the patient receives, via infusion, subsets of immune system cells that tackle and kill the affected cells. Hematopoietic stem cell transplantation is the most common type of cell therapy currently in use.
Although technological progress
