Dataset Information

Protein expression patterns of cell cycle regulators in operable breast cancer.

ABSTRACT:

Background-aim

To evaluate the prognostic role of elaborate molecular clusters encompassing cyclin D1, cyclin E1, p21, p27 and p53 in the context of various breast cancer subtypes.

Methods

Cyclin E1, cyclin D1, p53, p21 and p27 were evaluated with immunohistochemistry in 1077 formalin-fixed paraffin-embedded tissues from breast cancer patients who had been treated within clinical trials. Jaccard distances were computed for the markers and the resulted matrix was used for conducting unsupervised hierarchical clustering, in order to identify distinct groups correlating with prognosis.

Results

Luminal B and triple-negative (TNBC) tumors presented with the highest and lowest levels of cyclin D1 expression, respectively. By contrast, TNBC frequently expressed Cyclin E1, whereas ER-positive tumors did not. Absence of Cyclin D1 predicted for worse OS, while absence of Cyclin E1 for poorer DFS. The expression patterns of all examined proteins yielded 3 distinct clusters; (1) Cyclin D1 and/or E1 positive with moderate p21 expression; (2) Cyclin D1 and/or E1, and p27 positive, p53 protein negative; and, (3) Cyclin D1 or E1 positive, p53 positive, p21 and p27 negative or moderately positive. The 5-year DFS rates for clusters 1, 2 and 3 were 70.0%, 79.1%, 67.4% and OS 88.4%, 90.4%, 78.9%, respectively.

Conclusions

It seems that the expression of cell cycle regulators in the absence of p53 protein is associated with favorable prognosis in operable breast cancer.

SUBMITTER: Zagouri F

PROVIDER: S-EPMC5552326 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Publications

Protein expression patterns of cell cycle regulators in operable breast cancer.

Zagouri Flora F Kotoula Vassiliki V Kouvatseas George G Sotiropoulou Maria M Koletsa Triantafyllia T Gavressea Theofani T Valavanis Christos C Trihia Helen H Bobos Mattheos M Lazaridis Georgios G Koutras Angelos A Pentheroudakis George G Skarlos Pantelis P Bafaloukos Dimitrios D Arnogiannaki Niki N Chrisafi Sofia S Christodoulou Christos C Papakostas Pavlos P Aravantinos Gerasimos G Kosmidis Paris P Karanikiotis Charisios C Zografos George G Papadimitriou Christos C Fountzilas George G

PloS one 20170810 8

<h4>Background-aim</h4>To evaluate the prognostic role of elaborate molecular clusters encompassing cyclin D1, cyclin E1, p21, p27 and p53 in the context of various breast cancer subtypes.<h4>Methods</h4>Cyclin E1, cyclin D1, p53, p21 and p27 were evaluated with immunohistochemistry in 1077 formalin-fixed paraffin-embedded tissues from breast cancer patients who had been treated within clinical trials. Jaccard distances were computed for the markers and the resulted matrix was used for conductin ...[more]

PMID: 28797035

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Dataset Information

Protein expression patterns of cell cycle regulators in operable breast cancer.

Background-aim

Methods

Results

Conclusions

Publications

Protein expression patterns of cell cycle regulators in operable breast cancer.

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