Polo-like kinase 1 (Plk1) in cutaneous T-cell lymphoma.
BACKGROUND
Polo-like kinase 1 (Plk1) has multiple functions throughout mitosis. Plk1 levels are high in a number of cancers and haematological malignancies while being low in most differentiated tissues.


OBJECTIVE
To assess the immunoreactivity of Plk1 in cutaneous T-cell lymphoma (CTCL) as a potential therapeutic target, to differentiate Plk1 levels among lesion types and to compare the detection level of Plk1 in fresh frozen (f) vs. paraffin-embedded (p) tissue.


METHODS
Immunohistochemical staining of CTCL skin lesions with anti-Plk1 antibody was performed in a total of 65 biopsies from 49 patients with CTCL. Both f and p tissue was available for comparison in 46 biopsies.


RESULTS
Tumour-stage CTCL lesions displayed significantly more Plk1 (mean f 7·7%, p 8·8%) than patch (mean f 0·7%, p 2·0%) and plaque-stage lesions (mean f 1·1%, p 2·0%) (P < 0·05). Plk1 ranged from 0% to 18% in f and 0% to 24% in p samples. p tissue revealed a higher mean Plk1 detection rate of 4·4% compared with 2·9% in f tissue with no statistical significance.


CONCLUSIONS
Our results indicate that in CTCL, Plk1 is increased mainly in advanced lesions. Several Plk1 inhibitors have already shown promising results in preclinical and clinical phase I and II trials for different types of cancers with low adverse effects. Immunohistochemical detection of high Plk1 levels in patients with CTCL could help select individuals who might benefit from treatment with small molecule Plk1 inhibitors.
Department of Dermatology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA.
N
N
Stutz
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Nihal
G S
GS
Wood
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D015153:Blotting, Western; D018797:Cell Cycle Proteins / Q000032:analysis*; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D016410:Lymphoma, T-Cell, Cutaneous / Q000201:enzymology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011379:Prognosis; D017346:Protein Serine-Threonine Kinases / Q000032:analysis*; D011518:Proto-Oncogene Proteins / Q000032:analysis*; D015203:Reproducibility of Results; D012878:Skin Neoplasms / Q000201:enzymology* / Q000473:pathology; D000097869:Polo-Like Kinase 1
D014408:Biomarkers, Tumor; D018797:Cell Cycle Proteins; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D000097869:Polo-Like Kinase 1