Cellular kinetics and expression of bcl-2 and p53 in ductal carcinoma of the breast.
In this study, the expression of p53 (wild-type and mutated form) and bcl-2 in ductal carcinoma in situ (DCIS) and infiltrating ductal carcinoma (IDC) of the breast was evaluated by immunohistochemistry and PCR-SSCP and correlated with cellular kinetic parameters, i.e., mitotic index (MI) and apoptotic index (AI). The results showed a significant inverse correlation between p53 and bcl-2 expression in all cases of DCIS and IDC. In the DCIS group, two subgroups with different kinetic characteristics were identified. The first group was characterized by p53 positivity, bcl-2 negativity and high values of MI and AI; the other group was characterized by p53 negativity, bcl-2 positivity and low values of MI and AI. Conversely, in IDC some cases were p53 negative, bcl-2 positive and with high values of AI and MI, other cases were p53 positive, bcl-2 negative and with low AI and MI. Molecular biological analysis showed that p53 was wild-type in DCIS, while it was in the mutated form in IDC. These results suggest that in IDC mutated p53 contributes to a change in cellular kinetics and the selection of genetically aberrant cells, thereby favouring neoplastic progression. The coexistence of bcl-2 positivity and high AI could be explained by the presence of of apoptosis that work independently of bcl-2.
Megha
T
T
Institute of Pathologic Anatomy and Histology, University of Siena, Siena, Italy.
Ferrari
F
F
Arcuri
F
F
Lalinga
A V
AV
Lazzi
S
S
Cardone
C
C
Cevenini
G
G
Leoncini
L
L
Tosi
P
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000235:genetics* / Q000473:pathology*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D019254:Genes, bcl-2; D016158:Genes, p53; D006801:Humans; D007700:Kinetics; D008875:Middle Aged; D008940:Mitotic Index; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000032:analysis / Q000235:genetics
D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53