Takayuki Iwamoto
   Department   Kawasaki Medical School  Kawasaki Medical School, Department of Breast and Thyroid Surgery,
   Position   Assistant Professor
Article types 原著
Language English
Peer review Peer reviewed
Title Immunohistochemical Ki67 labeling index has similar proliferation predictive power to various gene signatures in breast cancer.
Journal Formal name：Cancer science
Abbreviation：Cancer Sci
ISSN code：13497006/13479032
Domestic / ForeginForegin
Volume, Issue, Page 103(8),pp.1508-12
Author and coauthor Naoki Niikura, Takayuki Iwamoto, Shinobu Masuda, Nobue Kumaki, Tang Xiaoyan, Masatoshi Shirane, Kazushige Mori, Banri Tsuda, Takuho Okamura, Yuki Saito, Yasuhiro Suzuki, Yutaka Tokuda
Authorship 2nd author
Publication date 2012/08
Summary The objective of this study was to examine the association between the immunohistochemical Ki67 labeling index (IHC Ki67), Ki67 mRNA expression level, and first-generation gene signatures in a cohort of breast cancer patients. We assessed associations between IHC Ki67 and first-generation gene signatures in a panel of 39 tumor samples, using an oligonucleotide microarray. Gene expression analyses included Ki67 alone (MKi67), 21-gene signature, mitosis kinome score signature, and genomic grade index. Correlation coefficients were calculated by Spearman's rank correlation test. In all cases, IHC Ki67, MKi67, and three genetic markers were highly correlated (ρ, 0.71-0.97). Estrogen receptor (ER)-positive cases showed strong correlations between IHC Ki67 and other signatures (ρ, 0.79-0.83). The ER-negative cases showed slightly lower correlations (ρ, 0.58-0.73). In ER-positive cases, the low IHC Ki67 group showed significantly longer relapse-free survival than the high IHC Ki67 group (P = 0.007). This difference was confirmed by multivariate analysis. Our data indicate that IHC Ki67 shows similar predictive power for proliferation in ER-positive cancers as genomic markers. Further study of IHC Ki67 is needed to define prognostic factors and predictive factors for chemotherapy using central laboratory assessment.
DOI 10.1111/j.1349-7006.2012.02319.x
PMID 22537114