Expression of alphav integrin family in gastric carcinomas: increased alphavbeta6 is associated with lymph node metastasis.
To investigate the alterations as to integrin expression in human gastric carcinomas, we analyzed the alphav subunit and 5 types of beta subunits using reverse transcription-polymerase chain reaction (RT-PCR) and competitive RT-PCR. The incidence of alphav, beta6 and beta8 expression was significantly higher in carcinoma tissues than in non-neoplastic gastric mucosal tissues (NGMTs). Out of 18 carcinoma cases with coexpression of alphav and beta6 subunits, which was demonstrated by RT-PCR, 17 cases (94%) showed lymph node metastasis (p = 0.0033). This tendency was confirmed by immunohistochemistry; most cases (23/28, 82%) in which alphavbeta6 integrin was immunohistochemically detected showed lymph node metastasis (p = 0.0193). RT-PCR and immunohistochemical studies showed that gastric carcinoma tissues expressed beta5 subunit in all cases. Furthermore, in a quantitative analysis using competitive RT-PCR, the mean level of beta5 expression was approximately 140 times higher in gastric carcinomas than in NGMTs. Most gastric carcinoma cases (27/38, 71%) were immunohistochemically positive for beta8 subunit. These findings suggest that some members of the alphav integrin family (alphavbeta5, alphavbeta6, alphavbeta8) are up-regulated, and that alphavbeta6 integrin may be involved in the lymphatic metastasis of gastric carcinomas.
Kawashima
Atsuhiro
A
Department of Molecular and Cellular Pathology, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan. kawasima@med.kanazawa-u.ac.jp
Tsugawa
Shuzo
S
Boku
Asami
A
Kobayashi
Masako
M
Minamoto
Toshinari
T
Nakanishi
Isao
I
Oda
Yoshio
Y
D000368:Aged; D000951:Antigens, Neoplasm / Q000096:biosynthesis*; D014408:Biomarkers, Tumor; D002277:Carcinoma / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D039564:Integrin alphaV / Q000096:biosynthesis*; D016023:Integrins / Q000096:biosynthesis*; D008207:Lymphatic Metastasis / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000378:metabolism / Q000473:pathology*; D015854:Up-Regulation
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D039564:Integrin alphaV; D016023:Integrins; C073878:integrin alphavbeta6