Loss of breast cancer metastasis suppressor 1 protein expression predicts reduced disease-free survival in subsets of breast cancer patients.
OBJECTIVE
This study aims to determine the effect of loss of breast cancer metastasis suppressor 1 (BRMS1) protein expression on disease-free survival in breast cancer patients stratified by estrogen receptor (ER), progesterone receptor (PR), or HER2 status, and to determine whether loss of BRMS1 protein expression correlated with genomic copy number changes.


METHODS
A tissue microarray immunohistochemical analysis was done on tumors of 238 newly diagnosed breast cancer patients who underwent surgery at the Cleveland Clinic between January 1, 1995 and December 31, 1996, and a comparison was made with 5-year clinical follow-up data. Genomic copy number changes were determined by array-based comparative genomic hybridization in 47 breast cancer cases from this population and compared with BRMS1 staining.


RESULTS
BRMS1 protein expression was lost in nearly 25% of cases. Patients with tumors that were PR negative (P=0.006) or HER2 positive (P=0.039) and <50 years old at diagnosis (P=0.02) were more likely to be BRMS1 negative. No overall correlation between BRMS1 staining and disease-free survival was observed. A significant correlation, however, was seen between loss of BRMS1 protein expression and reduced disease-free survival when stratified by either loss of ER (P=0.008) or PR (P=0.029) or HER2 overexpression (P=0.026). Overall, there was poor correlation between BRMS1 protein staining and copy number status.


CONCLUSIONS
These data suggest a mechanistic relationship between BRMS1 expression, hormone receptor status, and HER2 growth factor. BRMS1 staining could potentially be used in patient stratification in conjunction with other prognostic markers. Further, mechanisms other than genomic deletion account for loss of BRMS1 gene expression in breast tumors.
Hicks
David G
DG
Department of Clinical and Anatomic Pathology, General Surgery-Breast Center, Lerner Research Institute, The Cleveland Clinic, Cleveland, Ohio 44195, USA.
Yoder
Brian J
BJ
Short
Sarah
S
Tarr
Shannon
S
Prescott
Nichole
N
Crowe
Joseph P
JP
Dawson
Andrea E
AE
Budd
G Thomas
GT
Sizemore
Steven
S
Cicek
Muzaffer
M
Choueiri
Toni K
TK
Tubbs
Raymond R
RR
Gaile
Daniel
D
Nowak
Norma
N
Accavitti-Loper
Mary Ann
MA
Frost
Andra R
AR
Welch
Danny R
DR
Casey
Graham
G
D000328:Adult; D017668:Age of Onset; D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000378:metabolism* / Q000473:pathology / Q000628:therapy; D002277:Carcinoma / Q000175:diagnosis* / Q000453:epidemiology / Q000378:metabolism* / Q000473:pathology / Q000628:therapy; D016022:Case-Control Studies; D002880:Chromosomes, Human, Pair 11; D018572:Disease-Free Survival; D018628:Gene Dosage; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism
D008840:Microfilament Proteins; D009363:Neoplasm Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C486778:MTSS1 protein, human