title: Hedgehog signaling pathway regulates the growth of ovarian cancer spheroid forming cells.
abstract: The hedgehog (Hh) pathway has been shown to be activated in numerous malignancies as well as in cancer stem cells. We sought to determine the importance of the Hh pathway in regulating growth and development of ovarian cancer spheroid-forming cells (SFCs). Ovarian cancer cell lines (ES2, TOV112D, OV90, and SKOV3) as well as a normal ovarian epithelial cell line (IOSE80) were grown in non-adherent growth conditions to form SFCs. Western blot analysis was used to determine the expression of Hh pathway proteins SMOH, PTCH, GLI1. SFCs were treated with Hh agonists (SHH and IHH) as well as an Hh inhibitor (cyclopamine) to determine changes in spheroid growth and survival. All ovarian cancer cell lines readily formed spheroids in non-adherent growth conditions while IOSE80 failed to form SFCs. Compared to IOSE80, ovarian cancer cell lines demonstrated significant activation of the Hh pathway as defined by increased expression of intranuclear GLI1. Both Hh agonists demonstrated significant increases in spheroid volume of at least 42-fold for SHH-treated cells and 46-fold for IHH-treated cells. With regard to survival, SFCs were 30-50% more resistant to cyclopamine than their corresponding monolayer cells. Despite this resistance, inhibition of the Hh pathway with cyclopamine prevented further growth of SFCs with a 10-, 5-, and 4-fold restriction in growth for ES2, SKOV3, and TOV112D, respectively. The hedgehog pathway appears to be important in regulating growth of ovarian cancer spheroid-forming cells. The activation and inhibition of this pathway demonstrates significant correlation to enhanced growth and growth restriction, respectively.
authors.affiliation: University of South Alabama, Mitchell Cancer Institute, Mobile, AL 36604 , USA.
authors.forename: Anasuya
authors.initials: A
authors.lastname: Ray
authors.forename: Erhong
authors.initials: E
authors.lastname: Meng
authors.forename: Eddie
authors.initials: E
authors.lastname: Reed
authors.forename: Lalita A
authors.initials: LA
authors.lastname: Shevde
authors.forename: Rodney P
authors.initials: RP
authors.lastname: Rocconi
mesh_terms: D002460:Cell Line; D045744:Cell Line, Tumor; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D005260:Female; D053823:Hedgehog Proteins / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D010051:Ovarian Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D010053:Ovary / Q000166:cytology / Q000378:metabolism; D000072079:Patched Receptors; D000072081:Patched-1 Receptor; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D000072086:Smoothened Receptor; D018874:Spheroids, Cellular; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014704:Veratrum Alkaloids / Q000494:pharmacology; D000071676:Zinc Finger Protein GLI1
chemical_list: C400551:GLI1 protein, human; D053823:Hedgehog Proteins; C509246:IHH protein, human; C000606236:PTCH1 protein, human; D000072079:Patched Receptors; D000072081:Patched-1 Receptor; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; C509239:SHH protein, human; C491023:SMO protein, human; D000072086:Smoothened Receptor; D014157:Transcription Factors; D014704:Veratrum Alkaloids; D000071676:Zinc Finger Protein GLI1; C000541:cyclopamine