Article

Full sequencing of TP53 identifies identical mutations within in situ and invasive components in breast cancer suggesting clonal evolution.

Department of Surgical Sciences, Uppsala University, Uppsala SE 75105, Sweden.
Molecular oncology (impact factor: 4.1). 04/2009; 3(3):214-9. DOI:10.1016/j.molonc.2009.03.001 pp.214-9
Source: PubMed

ABSTRACT In breast cancer, previous studies have suggested that somatic TP53 mutations are likely to be an early event. However, there are controversies regarding the cellular origin and linear course of breast cancer. The purpose of this study was to investigate tumor evolution in breast cancer by analyzing TP53 mutation status in tumors from various stages of the disease. The entire coding sequence of TP53 was sequenced in a cohort of pure ductal carcinoma in situ (DCIS), pure invasive cancer (≤15mm) and mixed lesions (i.e. invasive cancer with an in situ component). Of 118 tumor samples, 19 were found to harbor a TP53 mutation; 5 (15.6%) of the pure DCIS, 4 (10.5%) of the pure invasive cancers and 10 (20.8%) of the mixed lesions. In the mixed lesions, both the invasive and the DCIS components showed the same mutation in all 5 cases where the two components were successfully microdissected. Presence of the same mutation in both DCIS and invasive components from the same tumor indicates same cellular origin. The role of mutant TP53 in the progression of breast cancer is less clear and may vary between subtypes.

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    Article: Frequent aberrant DNA methylation of ABCB1, FOXC1, PPP2R2B and PTEN in ductal carcinoma in situ and early invasive breast cancer.
    Aslaug Aa Muggerud, Jo Anders Rønneberg, Fredrik Wärnberg, Johan Botling, Florence Busato, Jovana Jovanovic, Hiroko Solvang, Ida Bukholm, Anne-Lise Børresen-Dale, Vessela N Kristensen, Therese Sørlie, Jörg Tost
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    Breast cancer research: BCR 01/2010; 12(1):R3. · 5.24 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

118 tumor samples
 
5 cases
 
breast cancer
 
DCIS components
 
entire coding sequence
 
invasive cancer
 
invasive components
 
linear course
 
mixed lesions
 
mutant TP53
 
pure DCIS
 
pure ductal carcinoma
 
pure invasive cancer
 
pure invasive cancers
 
situ component
 
somatic TP53 mutations
 
TP53 mutation
 
TP53 mutation status
 
tumor evolution
 
two components