Human Nanog pseudogene8 promotes the proliferation of gastrointestinal cancer cells.
There is emerging evidence that human solid tumor cells originate from cancer stem cells (CSCs). In cancer cell lines, tumor-initiating CSCs are mainly found in the side population (SP) that has the capacity to extrude dyes such as Hoechst 33342. We found that Nanog is expressed specifically in SP cells of human gastrointestinal (GI) cancer cells. Nucleotide sequencing revealed that NanogP8 but not Nanog was expressed in GI cancer cells. Transfection of NanogP8 into GI cancer cell lines promoted cell proliferation, while its inhibition by anti-Nanog siRNA suppressed the proliferation. Immunohistochemical staining of primary GI cancer tissues revealed NanogP8 protein to be strongly expressed in 3 out of 60 cases. In these cases, NanogP8 was found especially in an infiltrative part of the tumor, in proliferating cells with Ki67 expression. These data suggest that NanogP8 is involved in GI cancer development in a fraction of patients, in whom it presumably acts by supporting CSC proliferation.
Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. uchino13@intmed1.med.kyushu-u.ac.jp
Keita
K
Uchino
Gen
G
Hirano
Minako
M
Hirahashi
Taichi
T
Isobe
Tsuyoshi
T
Shirakawa
Hitoshi
H
Kusaba
Eishi
E
Baba
Masazumi
M
Tsuneyoshi
Koichi
K
Akashi
D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D017931:DNA Primers / Q000235:genetics; D005770:Gastrointestinal Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D018398:Homeodomain Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D000071317:Nanog Homeobox Protein; D009368:Neoplasm Transplantation; D014411:Neoplastic Stem Cells / Q000378:metabolism / Q000473:pathology; D011544:Pseudogenes; D034741:RNA, Small Interfering / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D014162:Transfection; D014183:Transplantation, Heterologous
D017931:DNA Primers; D018398:Homeodomain Proteins; C486780:NANOG protein, human; D000071317:Nanog Homeobox Protein; D034741:RNA, Small Interfering; D011994:Recombinant Proteins