PIK3CA in breast carcinoma: a mutational analysis of sporadic and hereditary cases.
The PI3K-Akt cascade is a key signaling pathway involved in cell proliferation, survival, and growth. Activating PIK3CA mutations have been reported in breast carcinoma (BC). The aim of this study was to characterize the PIK3CA mutations at exons 9 and 20 in a series of 176 sporadic and 22 hereditary BCs and to correlate the results with clinicopathologic parameters and survival. In sporadic BC, 68 missense mutations were detected. PIK3CA mutations were significantly associated with ER+ in HER2-negative cases. A higher frequency of PIK3CA mutations was present in lobular carcinoma compared with ductal carcinoma (50% vs. 35%). There was no association between the survival and PIK3CA mutational status. In hereditary BC, PIK3CA mutations were found only in the BRCA2 group. The PIK3CA mutation seems to characterize the luminal-type BC, in both sporadic and BRCA2 mutated forms, and is absent in the basal-type BC, in both the sporadic and BRCA1 mutated forms.
Division of Surgical, Molecular and Ultrastructural Pathology, Department of Oncology, University of Pisa, University Hospital of Pisa, Italy.
Angela
A
Michelucci
Claudio
C
Di Cristofano
Azzurra
A
Lami
Paola
P
Collecchi
Adelaide
A
Caligo
Nicola
N
Decarli
Martina
M
Leopizzi
Paolo
P
Aretini
Gloria
G
Bertacca
Romana Prosperi
RP
Porta
Sergio
S
Ricci
Carlo
C
Della Rocca
Giorgio
G
Stanta
Generoso
G
Bevilacqua
Andrea
A
Cavazzana
D000230:Adenocarcinoma / Q000235:genetics* / Q000378:metabolism / Q000401:mortality / Q000556:secondary; D002288:Adenocarcinoma, Mucinous / Q000235:genetics / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D051017:Apoptosis Regulatory Proteins; D024682:BRCA2 Protein / Q000235:genetics; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D018275:Carcinoma, Lobular / Q000235:genetics / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D058534:Class I Phosphatidylinositol 3-Kinases; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D018095:Germ-Line Mutation; D006801:Humans; D007558:Italy / Q000453:epidemiology; D053208:Kaplan-Meier Estimate; D008198:Lymph Nodes / Q000473:pathology; D008875:Middle Aged; D020125:Mutation, Missense / Q000235:genetics*; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics* / Q000378:metabolism; D015996:Survival Rate; D044767:Ubiquitin-Protein Ligases / Q000235:genetics
D051017:Apoptosis Regulatory Proteins; C118024:BLID protein, human; D024682:BRCA2 Protein; C551750:BRCA2 protein, human; D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; C111164:BRAP protein, human; D044767:Ubiquitin-Protein Ligases; D019869:Phosphatidylinositol 3-Kinases; D058534:Class I Phosphatidylinositol 3-Kinases; C484760:PIK3CA protein, human