Ovarian stem cells—resolving controversies
- 295 Downloads
A recent review on ovarian stem cells by Horan and Williams entitled “Oocyte Stem Cells: Fact or Fantasy?” suggests that the debate on ovarian stem cells (OSCs) is still not over. They did not even discuss the presence of two distinct populations of stem cells in the ovary in their review. OSCs are located in the ovary surface epithelium and Tilly’s group reported them in the size range of 5–8 μm whereas Virant-Klun’s group has reported pluripotent, 2–4 μm OSCs. Our group reported OSCs of two distinct sizes including pluripotent very small embryonic-like stem cells (VSELs) which are smaller in size than RBCs (similar to those reported by Virant-Klun’s group) and slightly bigger (similar to those reported by Tilly’s group) tissue committed progenitors (OSCs) that presumably differentiate from VSELs. These stem/progenitor cells express receptors for follicle stimulating hormone (FSH) and are activated by FSH. Our opinion article provides explanation to several open-ended questions raised in the review on OSCs by Horan and Williams. VSELs survive chemotherapy; maintain life-long homeostasis; loss of their function due to a compromised niche results in age-related senescence and presence of overlapping pluripotent markers suggest that they may also be implicated in epithelial ovarian cancers.
KeywordsOvary Stem cells VSELs Pluripotent Menopause Cancer
Authors acknowledge the earlier students and project staff in the lab who also contributed to the field. Also help from various funding agencies is also acknowledged. NIRRH accession number for the manuscript is OTH/501/07-2017.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- 4.Parte S, Bhartiya D, Telang J, Daithankar V, Salvi V, Zaveri K, et al. Detection, characterization, and spontaneous differentiation in vitro of very small embryonic-like putative stem cells in adult mammalian ovary. Stem Cells Dev. 2011; https://doi.org/10.1089/scd.2010.0461.
- 7.Bhartiya D. Ovarian stem cells are always accompanied by very small embryonic-like stem cells in adult mammalian ovary. J Ovarian Res. 2015; https://doi.org/10.1186/s13048-015-0200-0.
- 14.Zarate-Garcia L, Lane SI, Merriman JA, Jones KT. FACS-sorted putative oogonial stem cells from the ovary are neither DDX4-positive nor germ cells. Sci Rep. 2016;15(6):279–91.Google Scholar
- 18.Parte S, Bhartiya D, Patel H, Daithankar V, Chauhan A, Zaveri K, et al. Dynamics associated with spontaneous differentiation of ovarian stem cells in vitro. J Ovarian Res. 2014; https://doi.org/10.1186/1757-2215-7-25.
- 22.Bhartiya D, Sriraman K, Parte S, Patel H. Ovarian stem cells: absence of evidence is not evidence of absence. J Ovarian Res. 2013; https://doi.org/10.1186/1757-2215-6-65.
- 24.Bhartiya D, Sriraman K, Gunjal P, Modak H. Gonadotropin treatment augments postnatal oogenesis and primordial follicle assembly in adult mouse ovaries? J Ovarian Res. 2012; https://doi.org/10.1186/1757-2215-5-32.
- 25.Patel H, Bhartiya D, Parte S, Gunjal P, Yedurkar S, Bhatt M. Follicle stimulating hormone modulates ovarian stem cells through alternately spliced receptor variant FSH-R3. J Ovarian Res. 2013; https://doi.org/10.1186/1757-2215-6-52.
- 26.Bhartiya D, Parte S, Patel H, Sriraman K, Zaveri K, Hinduja I. Novel action of FSH on stem cells in adult mammalian ovary induces postnatal oogenesis and primordial follicle assembly. Stem Cells Int. 2016; https://doi.org/10.1155/2016/5096596.
- 27.Fazeli Z, Abedindo A, Omrani MD, Ghaderian SMH. Mesenchymal stem cells (MSCs) therapy for recovery of fertility: a systematic review. Stem Cell Rev. 2017; https://doi.org/10.1007/s12015-017-9765-x.
- 28.McLaughlin M, Kelsey TW, Wallace WH, Anderson RA, Telfer EE. Non-growing follicle density is increased following adriamycin, bleomycin, vinblastine and dacarbazine (ABVD) chemotherapy in the adult human ovary. HumReprod. 2017;32(1):165–74.Google Scholar
- 29.Parte S, Bhartiya D, Manjramkar DD, Chauhan A, Joshi A. Stimulation of ovarian stem cells by follicle stimulating hormone and basic fibroblast growth factor during cortical tissue culture. J Ovarian Res. 2013; https://doi.org/10.1186/1757-2215-6-20.
- 33.Bhartiya D, Anand S, Parte S. VSELs may obviate cryobanking of gonadal tissue in cancer patients for fertility preservation. J Ovarian Res. 2015; https://doi.org/10.1186/s13048-015-0199-2.
- 34.Bhartiya D, Anand S, Patel H, Parte S. Making gametes from alternate sources of stem cells: past, present and future. Reprod Biol Endocrinol. 2014; https://doi.org/10.1186/s12958-017-0308-8.
- 35.Bhartiya D. Letter to the editor: rejuvenate eggs or regenerate ovary? Mol Cell Endocrinol. 2017; https://doi.org/10.1016/j.mce.2017.03.008.
- 37.Bhartiya D. Pluripotent stem cells in adult tissues: struggling to be acknowledged over two decades. Stem Cell Rev. 2017; https://doi.org/10.1007/s12015-017-9756-y.
- 39.Reardon S. Mutated mitochondria could hold back stem-cell therapies. Nature. 2016; https://doi.org/10.1038/nature.2016.1975.
- 43.Virant-Klun I, Kenda-Suster N, Smrkolj S. Small putative NANOG, SOX2, and SSEA-4-positive stem cells resembling very small embryonic-like stem cells in sections of ovarian tissue in patients with ovarian cancer. J Ovarian Res. 2016; https://doi.org/10.1186/s13048-016-0221-3.