Oct4 expression in adult human stem cells: evidence in support of the stem cell theory of carcinogenesis.
The Oct3/4 gene, a POU family transcription factor, has been noted as being specifically expressed in embryonic stem cells and in tumor cells but not in cells of differentiated tissues. With the ability to isolate adult human stem cells it became possible to test for the expression of Oct3/4 gene in adult stem cells and to test the stem cell theory of carcinogenesis. Using antibodies and PCR primers we tested human breast, liver, pancreas, kidney, mesenchyme and gastric stem cells, the cancer cell lines HeLa and MCF-7 and human, dog and rat tumors for Oct4 expression. The results indicate that adult human stem cells, immortalized non-tumorigenic cells and tumor cells and cell lines, but not differentiated cells, express Oct4. Oct4 is expressed in a few cells found in the basal layer of human skin epidermis. The data demonstrate that adult stem cells maintain expression of Oct4, consistent with the stem cell hypothesis of carcinogenesis.
Tai
Mei-Hui
MH
National Food Safety Toxicology Center, Department of Pediatrics and Human Development, Michigan State University, East Lansing, MI 48824, USA.
Chang
Chia-Cheng
CC
Kiupel
Matti
M
Webster
Joshua D
JD
Olson
L Karl
LK
Trosko
James E
JE
D000818:Animals; D001940:Breast / Q000166:cytology / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology*; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004285:Dogs; D006367:HeLa Cells; D006801:Humans; D007668:Kidney / Q000166:cytology / Q000378:metabolism; D008099:Liver / Q000166:cytology / Q000378:metabolism; D050814:Octamer Transcription Factor-3; D010179:Pancreas / Q000166:cytology / Q000378:metabolism; D051381:Rats; D012867:Skin / Q000166:cytology* / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*
D004268:DNA-Binding Proteins; D050814:Octamer Transcription Factor-3; C494173:POU5F1 protein, human; D014157:Transcription Factors