Each year, over half a million head and neck cancer patients are treated with radiotherapy, which results in the severe dry mouth syndrome, xerostomia, due to co-radiation of healthy salivary glands. Poor quality of life in such patients is a result of conditions associated with xerostomia such as hyposalivation, dental caries, fungal infections, decaying teeth, and taste and masticatory dysfunctions. Current therapies to rescue hyposalivation provide temporary relief and are largely ineffective; thus, new therapies for permanent tissue repair are needed. Our lab has deep expertise in cutting-edge salivary glands stem cell research, and was the first to demonstrate the clinical potential of KIT+ (c-Kit, CD117) stem/progenitor cells in rescuing hyposalivation. However, this population of stem/progenitor cells decreases with age, currently compromising our ability to efficiently use these cells for therapy. Our current work shows that transcription factor SOX10 plays a major role in the proliferation and differentiation potential of KIT+ cells. For example, epithelial depletion of Sox10 results in loss of KIT+ and pro-acinar cells in the fetal stages. However, it is unclear whether SOX10 is required for expansion and multi-potency, i.e. the ability to differentiate into all epithelial cell types, of KIT+ cells through adulthood. Based on existing evidence, we hypothesize that SOX10 plays a central role in the expansion and differentiation of all KIT+ cells. To test this hypothesis, we will lineage trace epithelial KIT+SOX10+ cells in the submandibular gland using inducible mouse systems. We will also assess forced overexpression of SOX10 to expand KIT+ cells. Overall, these studies will elucidate whether SOX10 marks multi-potent KIT+ stem cells, and can be applied to expand KIT+ stem cells. The scientific ideas proposed here will expand our knowledge of salivary gland stem cells, and will significantly improve future hyposalivation rescue stem cell-based therapies.

Public Health Relevance

Over half a million head-and-neck cancer patients suffering from irradiation-induced xerostomia resulting in severe hyposalivation are deprived of long-term therapeutics because, in part, not much is known about the mechanisms regulating the salivary gland stem cells. Here we propose to determine whether SOX10 marks multi-potent stem cells, and elucidate its prospective role in expanding the stem cells in vitro and in vivo. This work will aid current proposals of stem cell-based therapeutics for rescuing hyposalivation in head-and-neck cancer patients.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Individual Predoctoral NRSA for M.D./Ph.D. Fellowships (ADAMHA) (F30)
Project #
5F30DE027605-02
Application #
9633917
Study Section
NIDR Special Grants Review Committee (DSR)
Program Officer
Frieden, Leslie A
Project Start
2017-12-01
Project End
2023-11-30
Budget Start
2018-12-01
Budget End
2019-11-30
Support Year
2
Fiscal Year
2019
Total Cost
Indirect Cost
Name
University of Michigan Ann Arbor
Department
Type
Schools of Dentistry/Oral Hygn
DUNS #
073133571
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109