Proliferation marker securin identifies favourable outcome in invasive ductal breast cancer.
We introduce a new proliferation marker, securin (pituitary tumour-transforming 1 (PTTG1)), analysed in invasive ductal breast carcinomas by cDNA microarrays and immunohistochemistry. In cDNA microarray of a total of 4000 probes of genes, securin was revealed with a significant change in expression among the several proliferation-related genes studied. The value of securin as a proliferation marker was verified immunohistochemically (n=44) in invasive ductal breast cancer. In follow-up analyses of the sample of patients, the prognostic value of securin was compared with the established markers of breast cancer proliferation, Ki-67 and mitotic activity index (MAI). Our results of a small sample of patients suggest that low securin expression identifies a distinct subgroup of more favourable outcome among patients with high Ki-67 immunoexpression or high MAI. In univariate analysis of Cox's regression, 10-unit increment of securin immunopositivity was associated with a 2.3-fold overall risk of death due to breast cancer and a 7.1-fold risk of death due to breast cancer in the sample of patients stratified according to the cutoff points of 10 and 20% of securin immunopositivity. We suggest that securin immunostaining is a promising and clinically applicable proliferation marker. The finding urges further prognostic studies with a large sample of patients.
Talvinen
K
K
Department of Pathology, Turku University Hospital, University of Turku, Kiinamyllynkatu 10, FIN-20520 Turku, Finland. kattal@utu.fi
Tuikkala
J
J
Nevalainen
O
O
Rantanen
A
A
Hirsimäki
P
P
Sundström
J
J
Kronqvist
P
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000096:biosynthesis* / Q000235:genetics; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000096:biosynthesis / Q000235:genetics; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D015203:Reproducibility of Results; D064249:Securin
D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D064249:Securin; C578002:pituitary tumor-transforming protein 1, human