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Updated: Aug 7, 2026

Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols
Published on: June 6, 2017
Cell cycle control by p21, p27 and p53 in Merkel cell carcinoma
Virve Koljonen1, Erkki Tukiainen, Caj Haglund
1Department of Plastic Surgery and 2Gastroenterological and General Surgery, Helsinki University Hospital, Finland. virve.koljonen@hus.fi
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.
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