Transcript BP1 EXPRESSION

ACTIVATION OF BP1 IS
ASSOCIATED WITH
AGGRESSIVE BREAST
CANCER
PATRICIA BERG, PH.D.
pBP1 IS AN ISOFORM OF THE
DLX4 GENE
BP1
DLX7
DLX4
CHASE ET AL, 2002. MOL. CELL. BIOL. 22:2505-2514
NOTE: BP1 AND DLX4 ARE NOT INTERCHANGEABLE
TERMS
CHARACTERISTICS OF BP1
BELONGS TO THE DISTAL-LESS (DLX) FAMILY
DLX GENES ARE HIGHLY CONSERVED: FOUND
IN DROSOPHILA, ZEBRAFISH, FROGS,
CHICKENS, MICE AND HUMANS
IMPORTANT FOR CRANIOFACIAL, LIMB, TOOTH
AND OCULAR DEVELOPMENT IN MICE
CHARACTERISTICS OF BP1
(CONT)
ENCODES A TRANSCRIPTION FACTOR THAT
REGULATES CASCADES OF GENES, INCLUDING
ONCOGENES
A POTENTIAL ONCOGENE ACTIVATED IN A
NUMBER OF DIFFERENT TYPES OF CANCER
ACTIVATION OF BP1 IN CANCER

BREAST CANCER – 80% (FU ET AL, 2003)

PROSTATE CANCER – 70% (SCHWARTZ ET AL, 2005)

ACUTE MYELOID LEUKEMIA – 63% (HAGA ET AL,
2000)
ACTIVATION OF BP1 IN CANCER
(CONT)

OVARIAN CANCER – ~ 65% (and HARA ET AL, 2007)

LUNG CANCER – ~ 45% (and YU ET AL, 2008)

COLON CANCER – ~40%
Berg, PE and Kirolikar, S. 2011. Atlas Genet Cytogenet Oncol
Haematol. 15: 658-661.
GENES INVOLVED IN NONHEREDITARY BREAST CANCER
GENE
FREQUENCY
HER-2
20 – 30%
C-MYC
20 – 30%
CYCLIN E
30%
EGFR
25-35%
CYCLIN D1
BP1
50% (20% AMPLIFIED)
80%
ASSOCIATION BETWEEN BP1 mRNA EXPRESSION
AND
CLINICO-PATHOLOGICAL DATA
Factors
ER Status
Negative
Positive
PR Status
Negative
Positive
Race
Caucasian
African American
FU et al, 2003. Br. Ca. Res. 5: 82-87.
BP1 mRNA
Negative
Positive
p value
0.03
0 (0%)
7 (27%)
18 (100%)
19 (73%)
0.02
1 (4.0%)
6 (33%)
24 (96%)
12 (67%)
0.04
6 (43%)
3 (11%)
8 (57%)
25 (89%)
BP1 AND BREAST CANCER
PROGRESSION
MAN ET AL, 2005. BR. CA. RES. & TREAT. 90: 241-247.
BP1 and Progression
NORMAL
0%
n=30
HYPERPLASIA
(IDH)
21%
n=70
DUCTAL CARCINOMA
IN SITU (DCIS)
INVASIVE DUCTAL
CARCINOMA (IDC)
46%
n=100
81%
n=100
N
SUMMARY
AS TUMOR PROGRESSION OCCURS, THERE IS
AN INCREASE IN
1. THE PERCENTAGE OF BP1 POSITIVE
TUMORS
2. THE PERCENTAGE OF BP1 POSITIVE
CELLS PER TUMOR
3. BP1 STAINING INTENSITY (BP1
EXPRESSION)
INFLAMMATORY BREAST
CANCER





RAPIDLY PROGRESSIVE
HIGHLY ANGIOGENIC AND INVASIVE
5 YR SURVIVAL LESS THAN 45% VS 86% IN
NON-IBC
LESS THAN HALF HAVE A DISCRETE MASS
REPRESENT 1-5% OF ALL BREAST CANCERS
IN CAUCASIANS AND 10% IN AFRICAN
AMERICANS
BP1 AND INFLAMMATORY BREAST
CANCER

100% OF IBC TUMORS WERE BP1 POSITIVE
(N=45) WITH 95% OF CELLS POSITIVE

9 PAIRED METASTATIC LYMPH NODES
AVAILABLE; ALL WERE BP1 POSITIVE

TUMOR CELLS IN BLOOD VESSELS AND
LYMPHATIC CHANNELS WERE BP1 POSITIVE
Man et al, 2009. Ca. Biomarkers 5: 9-17.
BP1 EXPRESSION IN LYMPHATIC
CHANNELS AND BLOOD VESSELS
LYMPHATIC CHANNELS
BLOOD VESSELS
HOW IS BP1 ACTIVATED?
A. DNA AMPLIFICATION
B. ESTRADIOL
A. DNA AMPLIFICATION
AMPLIFICATION OF BP1 WAS OBSERVED
BY FISH IN 22% OF PRIMARY BREAST
TUMORS AND IN 24% of MATCHED SLN
METASTASES FROM PATIENTS WITH
INVASIVE DUCTAL BREAST CANCER*
NOTE: BP1 MAPS TO 17Q21-22**
* TORRESON ET AL, 2014; CAVALLI ET AL, 2008.
** FU ET AL, 2001. GENE 278: 131-139.
FISH ANALYSIS OF BP1
FISH analysis of FFPE sections of a primary breast tumor (left)
and SLN metastasis (right) from one patient showing
amplification of the BP1 gene
CORRELATION BETWEEN BP1
AMPLIFICATION AND
EXPRESSION

ALL CASES SHOWING BP1
AMPLIFICATION ALSO SHOWED BP1
EXPRESSION BY IHC

BP1 POSITIVITY WAS ALSO SEEN IN
CASES WITHOUT AMPLIFICATION
BP1 AND HER2
BP1 AND HER2 MAP NEAR EACH OTHER
AND ARE CO-AMPLIFIED 78% OF THE TIME
IN PRIMARY TUMORS AND 100% OF THE
TIME IN SLN
B. ESTRADIOL STIMULATES BP1 IN
MCF7 CELLS
ERα BINDS TO BP1 INTRON I
ChIP
1.
LADDER
2.3 INPUT CONTROL FOR ERE ELEMENT IN
EXON I AND INTRON I
4.5 AFTER IP WITH ERα AB
BP1 ACTIVATES ONCOGENES
GENE
ASSOCIATED WITH
MMP9
INITIATION, INVASION,
METASTASIS
BCL-2
ANTI-APOPTOTIC (Stevenson et
al, 2007)
C-MYC
PROLIFERATION,
DIFFERENTIATION, APOPTOSIS
(Trinh et al, 2011)
MET
GROWTH, ANGIOGENESIS,
METASTASIS
ANGIOGENESIS (Hara et al, 2007)
VEGF
BP1 EXPRESSION IS
ASSOCIATED WITH
AGGRESSIVENESS
MEASURES OF AGGRESSIVENESS
BP1 INCREASES:

GROWTH IN THE ABSENCE OF SERUM

GROWTH IN SOFT AGAR (ANCHORAGE
INDEPENDENT GROWTH)

INVASION THROUGH MATRIGEL

CHANGES IN TUMOR FORMATION IN NUDE
MICE
GROWTH IN SOFT AGAR
D4
V1
O2
O4
D13
CELL LINES OVEREXPRESSING BP1 WERE
INJECTED INTO THE FAT PADS OF NUDE
MICE
Submitted
EFFECT OF BP1 ON TUMOR
GROWTH IN MICE
ESTROGEN INDEPENDENT
TUMOR FORMATION IN MICE
Cell Type Injected
Estrogen
added
Absence of
Estrogen
MCF-7/EV-1
4/10 (40%)
0/10 (0%)
MCF-7/BP1-2
10/15 (67%)
2/10 (20%)
MCF-7/BP1-4
7/11 (64%)
2/10 (20%)
BP1 UPREGULATES ERα BOTH
DIRECTLY AND INDIRECTLY
SUBMITTED
DIRECT: BP1 ACTIVATES ERα RNA
BY BINDING TO IVS1
INDIRECT: BP1 STABILIZES ERα BY
UPREGULATING p300
(p300 ACETYLATES ERα)
mRNA
p300
PROTEIN
ACTIN
V1
O1
INDIRECT: BP1 AND BRCA1

BRCA1 INHIBITS ERα PROTEIN VIA
UBIQUITINATION

BP1 REPRESSES BRCA1 BY BINDING TO ITS
FIRST INTRON (Kluk et al, 2010), WHICH IS
PREDICTED TO FURTHER INCREASE THE
LEVEL OF ERα
MODEL
CONCLUSIONS
 BP1
EXPRESSION MAY BE
PROGNOSTIC IN BREAST CANCER
 BP1
IS A NEW POTENTIAL
THERAPEUTIC TARGET
ACKNOWLEDGEMENTS
GWUMC
SAURABH KIROLIKAR
SANKET AWATE
DANIEL RHEEY
BIN JIN HUANG
KELLIE YAMANE
YASSI FALLAH
ARNOLD SCHWARTZ
PAUL LEVINE
SAMUEL SIMMENS
SIDNEY FU
JHU
JUDITH KARP
FARHAD VESUNA
VENU RAMAN
AFIP
YAN-GAO MAN
GEORGETOWN
LUCIANE CAVALLI
DAVID GEFFEN SOM
NCI
BARBARA
VONDERHAAR
JOSEPH PINZONE