AUTHOR=Ram Rachna , Brasch Helen D. , Dunne Jonathan C. , Davis Paul F. , Tan Swee T. , Itinteang Tinte 

TITLE=The Identification of Three Cancer Stem Cell Subpopulations within Moderately Differentiated Lip Squamous Cell Carcinoma

JOURNAL=Frontiers in Surgery

VOLUME=Volume 4 - 2017

YEAR=2017

URL=https://www.frontiersin.org/journals/surgery/articles/10.3389/fsurg.2017.00012

DOI=10.3389/fsurg.2017.00012

ISSN=2296-875X

ABSTRACT=Aim. To identify and characterize cancer stem cells (CSC) in moderately differentiated lip squamous cell carcinoma (MDLSCC). 
Method. MDLSCC samples underwent 3, 3-diaminobenzidine (DAB) immunohistochemical (IHC) staining for SCC marker EMA, CSC marker CD44 and embryonic stem cell markers NANOG, OCT4, SALL4, SOX2 and pSTAT3. Immunofluorescent (IF) IHC staining was performed in two MDLSCC samples. Western blotting (WB) was used to confirm the expression of the aforementioned proteins and their transcription activation was investigated using NanoString and qRT-PCR. 
Results. IHC staining demonstrated the presence of (1) an EMA+/CD44+/SALL4+/NANOG+/pSTAT3+/SOX2+/OCT4- CSC subpopulation within the tumor nests; (2) a CD44+/SALL4+/NANOG+/pSTAT3+/SOX2+/OCT4- CSC subpopulation and (3) a CD44+/SALL4+/NANOG+/pSTAT3+/SOX2+/OCT4+ CSC subpopulation within the stroma, between the tumor nests. NanoString and RT-PCR confirmed the presence of mRNA for CD44, SALL4, STAT3, SOX2 and OCT4, and WB confirmed the presence of NANOG, pSTAT3, SOX2 and OCT4.
Conclusion. This study demonstrates three putative CSC subpopulations within MDLSCC.