title: Cell cycle control by p21, p27 and p53 in Merkel cell carcinoma.
abstract: Merkel cell carcinoma (MCC) is an aggressive dermal tumour of neuroendocrine origin with poor prognosis. The role of cell cycle-regulatory proteins (p53/p21/p27) in MCC pathogenesis and their prognostic importance were evaluated. Twenty-four primary MCC specimens with corresponding clinical data were analysed by immunohistochemistry for p21, p27 and p53 antibodies. The stainings were evaluated semi-quantitatively and the results analysed statistically. p53 was negative in 80% and p21 in 71% of the samples. Positive staining for p27 was evident in 92% of the samples. However, the expression of these antibodies did not correlate with the outcome of the patient. The proportion of p53- and p21-negative samples seems to indicate that correction processes after DNA damage are not activated during MCC pathogenesis, a supposition that is supported by the aggressive nature of this tumour. Therefore, the expressions of the three studied cell cycle regulators cannot serve as prognostic markers for survival.
authors.affiliation: Department of Plastic Surgery and 2Gastroenterological and General Surgery, Helsinki University Hospital, Finland. virve.koljonen@hus.fi
authors.forename: Virve
authors.initials: V
authors.lastname: Koljonen
authors.forename: Erkki
authors.initials: E
authors.lastname: Tukiainen
authors.forename: Caj
authors.initials: C
authors.lastname: Haglund
authors.forename: Tom
authors.initials: T
authors.lastname: Böhling
mesh_terms: D014408:Biomarkers, Tumor / Q000096:biosynthesis*; D015266:Carcinoma, Merkel Cell / Q000378:metabolism* / Q000473:pathology*; D002453:Cell Cycle / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000096:biosynthesis*; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000096:biosynthesis; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000096:biosynthesis; D006801:Humans; D007150:Immunohistochemistry; D011379:Prognosis; D012189:Retrospective Studies; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis
chemical_list: D014408:Biomarkers, Tumor; C493956:CDKN1A protein, human; D018797:Cell Cycle Proteins; D050759:Cyclin-Dependent Kinase Inhibitor p21; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D050760:Cyclin-Dependent Kinase Inhibitor p27