Absence of tumor-specific over-expression of Polo-like kinase 1 (Plk1) in major non-Hodgkin lymphoma and relatively low expression of Plk1 in nasal NK/T cell lymphoma.
Based on the presence of the tumor-specific over-expression of Plk1 (polo-like kinases) in various malignancies, we examined Plk1 expression in nine cases of reactive follicular hyperplasia (RFH), 42 of diffuse large B cell lymphoma (DLBCL), 16 of follicular lymphoma (FL), and 10 of nasal NK/T lymphoma. There was no significant difference in the Plk1-positive cell percentage between RFH and DLBCL. The Plk1-positive cell percentage ranged from 6 to 20% with a median of 12.9% in DLBCL. In FL, Plk1-positivity was at most 7%. Plk1-positivity in nasal NK/T cell lymphoma (4.7-14.1% with a median of 9.2%) was significantly higher than that of FL and tended to be lower than DLBCL (p < 0.001, p = 0.05, respectively). Although a strong correlation between positive cell percentages for Plk1 and Ki-67 in these three lymphomas specified Plk1 as a proliferation marker (r = 0.83-0.91), the Plk1-positive cell percentage relative to the other proliferation markers tended to be particularly low in nasal NK/T cell lymphoma. In 41 cases of DLBCL, the positive cell percentages of Plk1 and Ki-67 were both correlated with overall survival. The 4-year overall survival rates by Kaplan-Meier analysis for Plk1-negative and positive patients were 80 and 38%, respectively (p = 0.02).
Imai
Hidenori
H
Department of Internal Medicine, Division of Hematology, Juntendo University School of Medicine, Tokyo, Japan.
Sugimoto
Koichi
K
Isobe
Yasushi
Y
Sasaki
Makoto
M
Yasuda
Hajime
H
Takeuchi
Kengo
K
Nakamura
Shinji
S
Kojima
Yuko
Y
Tomomatsu
Junichi
J
Oshimi
Kazuo
K
D015415:Biomarkers; D018797:Cell Cycle Proteins / Q000032:analysis* / Q000235:genetics; D049109:Cell Proliferation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis; D054391:Lymphoma, Extranodal NK-T-Cell / Q000737:chemistry* / Q000401:mortality; D008224:Lymphoma, Follicular / Q000737:chemistry; D016403:Lymphoma, Large B-Cell, Diffuse / Q000737:chemistry* / Q000401:mortality; D008228:Lymphoma, Non-Hodgkin / Q000737:chemistry* / Q000401:mortality; D009363:Neoplasm Proteins / Q000032:analysis / Q000235:genetics; D009669:Nose Neoplasms / Q000737:chemistry / Q000401:mortality; D011379:Prognosis; D017346:Protein Serine-Threonine Kinases / Q000032:analysis* / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000032:analysis* / Q000235:genetics; D016019:Survival Analysis; D000097869:Polo-Like Kinase 1
D015415:Biomarkers; D018797:Cell Cycle Proteins; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D000097869:Polo-Like Kinase 1