Heterogeneous expression of zinc-finger E-box-binding homeobox 1 plays a pivotal role in metastasis via regulation of miR-200c in epithelial-mesenchymal transition.
Although epithelial-mesenchymal transition (EMT) has been implicated as the pivotal event in metastasis, there is insufficient evidence related to EMT in clinical settings. Intratumor heterogeneity may lead to underestimation of gene expression representing EMT. In the present study, we investigated the expression of EMT-associated genes and microRNAs in primary colorectal cancer while considering intratumor heterogeneity. One-hundred and thirty-three multiple spatially separated samples were obtained from 8 patients with metastatic colorectal cancers and 8 with non-metastatic colorectal cancers, from the tumor center (TC), invasive front (IF) and metastasis. Differences in gene and microRNA expression were investigated by microarray and quantitative reverse-transcription PCR. Gene expression microarray analysis detected 7920 sites showing differing levels of gene expression among the TC, IF and metastasis. Expression of the EMT-associated gene zinc-finger E-box-binding homeobox 1 (ZEB1) significantly increased in the IF (p<0.01). To exclude individual differences, the expression ratio between TC and IF in each tumor was applied to analysis. This approach enabled recognition of the activation of the VEGF and Wnt signaling pathways, which were involved in metastasis via promotion of EMT. While no activation of these pathways was seen at the TC, regardless of whether tumors were metastatic or non-metastatic, they were preferentially activated at the IF in metastatic tumors, where high ZEB1 expression was seen in connection with decreased miR-200c expression. Multiple sampling in a tumor revealed that heterogeneous ZEB1 expression induced by EMT-associated signaling pathways played a pivotal role in metastasis via regulation of miR-200c.
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Yuta
Y
Muto
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Koichi
K
Suzuki
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Takaharu
T
Kato
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Shingo
S
Tsujinaka
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Kosuke
K
Ichida
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Yuji
Y
Takayama
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Taro
T
Fukui
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Nao
N
Kakizawa
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Fumiaki
F
Watanabe
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Masaaki
M
Saito
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Kazushige
K
Futsuhara
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Hiroshi
H
Noda
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Yasuyuki
Y
Miyakura
Nerima-Hikarigaoka Hospital, Nerima-ku, Tokyo 179-0072, Japan.
Fumio
F
Konishi
Department of Surgery, Saitama Medical Center, Jichi Medical University, Omiya-ku, Saitama 330-8503, Japan.
Toshiki
T
Rikiyama
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000235:genetics / Q000473:pathology*; D058750:Epithelial-Mesenchymal Transition; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D009362:Neoplasm Metastasis; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D060449:Wnt Signaling Pathway; D000071799:Zinc Finger E-box-Binding Homeobox 1 / Q000235:genetics*
C533896:MIRN200 microRNA, human; D035683:MicroRNAs; C486307:ZEB1 protein, human; D000071799:Zinc Finger E-box-Binding Homeobox 1