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factor, in their role in suppressing ER-dependent breast tumor registry data. Paraffi n-embedded blocks and
cancer cell growth and tumor genesis and maintenance hematoxylin and eosin (HE) slides of 291 patients with
of breast luminal-cell differentiation in vivo. Their use as initial DCIS were retrieved. Complete demographic data,
prognostic clinical biomarkers has recently been studied menopause state, hormone therapy use, family history,
in IC but not in DCIS . [10-13] FOXA1, originally called the prior history of pregnancy, mammography report (mass,
hepatocyte nuclear factor 3α, is a ubiquitous transcription calcifi cations), surgical treatment and adjuvant therapy,
factor expressed in liver, breast, prostate, lung, colon, and along with pathologic data were reviewed. All patients
pancreas that has both activator and repressor activity. As had undergone a core needle biopsy or needle localization
an activator, FOXA1 has the unique ability to bind to its excision biopsy for initial diagnosis. Two hundred and
target sites via altering chromatin structure facilitating nineteen cases who had complete follow-up, glass slides
ERα binding and thus promoting gene expression . [14,15] and tumor bocks were chosen for the study. Recurrence
FOXA1 may also act as a growth inhibitor via binding was defi ned as DCIS or invasive breast cancer in the
and activation of the p27 promoter, located within the same breast 1-year or more after the initial diagnosis
BRCA1-responsive element , [16,17] thus plays a critical role of DCIS. Nonrecurrence DCIS group included patients
in suppressing ER-dependent breast cancer cell growth who had DCIS or microinvasion (invasion ≤ 1 mm) or
and tumor genesis in vivo. [17] invasive cancer that was subsequently diagnosed at the
GATA-3, a member of the zinc fi nger DNA binding time of complete excision.
proteins, was originally discovered in its role in Procedure
T-lymphoid development into Th2 cells. In the breast,
[18]
GATA-3 was initially discovered to be associated with ER The project was approved by the University of Pittsburgh
expression in breast carcinomas and has subsequently Institutional Review Board. All cases were reviewed
[19]
been demonstrated in vivo to be highly expressed in the by two pathologists with confi rmation of nuclear grade,
mammary luminal epithelial cells, responsible for both as described by conventional features observed on the
development and maintenance of luminal cells fate . [20,21] HE slide. All other pathologic features were obtained
Like FOXA1, GATA-3 is also promising biomarker and from the original report. The tumor size measurement
the complex relationship between ERα, FOXA1, and was assessed either by size from microscopic or gross
GATA-3 is being better understood in order to refi ne the description or as an estimation based on tumor volume
hormone-responsive phenotype in IC, which will help from number of slides involved per total slides. Margins
both with therapy decision making and better prediction were considered clear (negative) defi ned as no link
of clinical outcomes. [21-23] GATA-3 has been identifi ed on the tumor and positive if less than 1 mm. Table 1
[20]
as an upstream promoter of FOXA1 transcription. shows complete clinical, radiological and pathologic
FOXA1 has been shown to be responsible for expression characteristics in relation to recurrence.
of at least 50% of ERα regulated genes [24-26] and thus Immunohistochemistry (IHC) was performed on the
has been proposed as the link between GATA-3 and selected paraffi n-embedded tumor block of the index
ERα. GATA-3 genes are involved with induction of DCIS lesion using the following biomarkers GATA-3,
[21]
FOXA1 expression, with increased activity in ER(+) FOXA1, ER, progesterone receptor (PR), Ki-67 and
carcinoma; therefore, the highest expression of FOXA1 HER2.
in IC should be seen in association with both GATA-3
and ERα expression, which has been seen in IC. Predilute rabbit monoclonal antibodies directed
[27]
[12]
However, this relationship has not yet been categorized against ER alpha (SP1), PR (1E2) and HER2 (4B5)
in DCIS. The specifi c aim of this study is to analyze the were purchased from Ventana Medical Systems
expression for the fi rst time in DCIS of novel biological Inc., Tucson, AZ, USA (VMSI). The manufacturer’s
transcription markers FOXA1, GATA-3, along with recommended protocols were followed, utilizing
established markers MIB-1 (Ki-67) and HER2-neu in CC1 for antigen unmasking, and iVIEW/DAB
ER(+) and ER(-) groups of DCIS. As it has been shown (Ventana Medical Systems, Inc.) for detecting the
in IC, we will investigate if there is a similar association antigen-antibody complex and a biotin block to inhibit
between FOXA1/GATA-3 with ERα in DCIS. The nonspecifi c staining of endogenous biotin. Mouse
secondary goal is to defi ne an expression profi le of monoclonal anti-GATA-3 (L50-823), purchased from
FOXA1, GATA-3 and other biomarkers that could predict BD Biosciences was diluted 1:300 and shared the same
recurrence in these DCIS groups and further stratify low protocol parameters as the previous mentioned. FOXA1
versus high-risk patients and impact treatment decisions. protein was detected using a goat polyclonal antibody
from Santa Cruz. Slides were pretreated in a steamer
Methods in Target Retrieval Solution, pH 6.0 (Dako) at 95 °C
for 20 min, then cooled at room temperature. Slides
Patients
were then incubated with anti-FOXA1 (1:400) followed
In our retrospective study, we identifi ed 2,434 women by Goat Immpress/DAB polymer for detection (Vector
diagnosed with DCIS from 1988 to 2009 from the Labs) [Table 2].

Journal of Cancer Metastasis and Treatment ¦ Volume 1 ¦ Issue 2 ¦ July 15, 2015 ¦ 85