TY - JOUR
T1 - Distinct expression of C4.4A in colorectal cancer detected by different antibodies
AU - Yamamoto, Hirofumi
AU - Oshiro, Ryota
AU - Ohtsuka, Masahisa
AU - Uemura, Mamoru
AU - Haraguchi, Naotsugu
AU - Nishimura, Junichi
AU - Takemasa, Ichiro
AU - Mizushima, Tsunekazu
AU - Doki, Yuichiro
AU - Mori, Masaki
N1 - Copyright:
Copyright 2019 Elsevier B.V., All rights reserved.
PY - 2013/1
Y1 - 2013/1
N2 - The metastasis-associated gene C4.4A encodes a glycolipid-anchored membrane protein expressed in several human malignancies. The present study aimed to perform a detailed assessment of C4.4A expression in colorectal cancer tissues, in terms of intra-cellular localization, intra-tumoral location and difference in molecular weight. To advance this goal, we developed three new antibodies against the C4.4A protein (two polyclonal Abs: C4.4A-119 and C4.4A-277 and one monoclonal Ab: C4.4A GPI-M) to use in addition to the two previously produced polyclonal Abs (C4.4A-81, C4.4A GPI-P). Antibody specificities were confirmed by absorption tests. Western blot analysis and immunohistochemistry showed that the C4.4A-119 and C4.4-277 Abs detected 70-kDa C4.4A, mainly in the cytoplasm, irrespective of intra-tumoral location. The C4.4A GPI-P and C4.4A GPI-M Abs reacted with the membranous ~40-kDa C4.4A, exclusively at the tumor invasive front, and each detected an identical tumor cell population. The tested antibodies showed varied C4.4A detection rates in 33 CRC tissues. The C4.4A-277 Ab yielded the highest positive rate in 29 of 33 CRC tissues (87.9%), while the C4.4A GPI-P and C4.4A GPI-M Abs each only showed 33.3% positivity. The present findings suggest that the GPI anchor signaling sequence may be essential for detecting membranous C4.4A at the invasive front of CRC tissues.
AB - The metastasis-associated gene C4.4A encodes a glycolipid-anchored membrane protein expressed in several human malignancies. The present study aimed to perform a detailed assessment of C4.4A expression in colorectal cancer tissues, in terms of intra-cellular localization, intra-tumoral location and difference in molecular weight. To advance this goal, we developed three new antibodies against the C4.4A protein (two polyclonal Abs: C4.4A-119 and C4.4A-277 and one monoclonal Ab: C4.4A GPI-M) to use in addition to the two previously produced polyclonal Abs (C4.4A-81, C4.4A GPI-P). Antibody specificities were confirmed by absorption tests. Western blot analysis and immunohistochemistry showed that the C4.4A-119 and C4.4-277 Abs detected 70-kDa C4.4A, mainly in the cytoplasm, irrespective of intra-tumoral location. The C4.4A GPI-P and C4.4A GPI-M Abs reacted with the membranous ~40-kDa C4.4A, exclusively at the tumor invasive front, and each detected an identical tumor cell population. The tested antibodies showed varied C4.4A detection rates in 33 CRC tissues. The C4.4A-277 Ab yielded the highest positive rate in 29 of 33 CRC tissues (87.9%), while the C4.4A GPI-P and C4.4A GPI-M Abs each only showed 33.3% positivity. The present findings suggest that the GPI anchor signaling sequence may be essential for detecting membranous C4.4A at the invasive front of CRC tissues.
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U2 - 10.3892/ijo.2012.1714
DO - 10.3892/ijo.2012.1714
M3 - Article
C2 - 23175173
AN - SCOPUS:84873658894
VL - 42
SP - 197
EP - 201
JO - International Journal of Oncology
JF - International Journal of Oncology
SN - 1019-6439
IS - 1
ER -