Elevated circulating sclerostin correlates with advanced disease features and abnormal bone remodeling in symptomatic myeloma: reduction post-bortezomib monotherapy.

Abstract

Sclerostin is a Wingless and Int-1 inhibitor, which is produced by osteocytes and inhibits osteoblast-driven bone formation. Sclerostin is implicated in the pathogenesis of bone loss in metabolic bone disorders but there is no information for its effect on multiple myeloma (MM)-related osteolytic disease. We evaluated circulating sclerostin in 157 newly diagnosed patients with symptomatic myeloma, in 25 with relapsed myeloma who received bortezomib monotherapy, in 21 patients with monoclonal gammopathy of undetermined significance (MGUS), and in 21 healthy controls. Patients with active myeloma had elevated circulating sclerostin compared to MGUS patients and controls (p < 0.01). MM patients who presented with fractures at diagnosis (n = 34) had very high levels of circulating sclerostin compared with all others (p < 0.01), whereas sclerostin correlated negatively with bone specific alkaline phosphatase (a bone formation marker; r = -0.541, p < 0.0001) and positively with C-telopeptide of collagen type-1 (a bone resorption marker; r = 0.524, p < 0.0001). Patients with International Staging System (ISS)-3 disease had higher circulating sclerostin compared to ISS-1 and ISS-2 MM (p = 0.001). Furthermore, patients with high sclerostin (upper quartile, n = 40) had a median survival of 27 months versus 98 months of all others (p = 0.031). Relapsed MM patients had higher levels of circulating sclerostin even compared to newly diagnosed patients (p < 0.01). Bortezomib monotherapy resulted in a reduction of sclerostin by almost 50% in both responders and non-responders. These results suggest that patients with active myeloma have elevated circulating sclerostin, which correlated with advanced disease features including severe bone disease. Our study indicates sclerostin as a possible target for the development of novel therapies to enhance osteoblast function in myeloma.

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Elevated circulating sclerostin correlates with advanced disease
features and abnormal bone remodeling in symptomatic
myeloma: reduction post-bortezomib monotherapy
Evangelos Terpos1, Dimitrios Christoulas1, Eirini Katodritou1, Cornelia Bratengeier2, Maria Gkotzamanidou1,
Eurydiki Michalis1, Sosana Delimpasi1, Anastasia Pouli1, John Meletis1, Efstathios Kastritis1,
Konstantinos Zervas1and Meletios A. Dimopoulos1
1Greek Myeloma Study Group, Greece
2Biomarker Design Forschungs GmbH, Vienna, Austria
Sclerostin is a Wingless and Int-1 inhibitor, which is produced by osteocytes and inhibits osteoblast-driven bone formation.
Sclerostin is implicated in the pathogenesis of bone loss in metabolic bone disorders but there is no information for its effect
on multiple myeloma (MM)-related osteolytic disease. We evaluated circulating sclerostin in 157 newly diagnosed patients
with symptomatic myeloma, in 25 with relapsed myeloma who received bortezomib monotherapy, in 21 patients with
monoclonal gammopathy of undetermined significance (MGUS), and in 21 healthy controls. Patients with active myeloma had
elevated circulating sclerostin compared to MGUS patients and controls (p < 0.01). MM patients who presented with fractures
at diagnosis (n 5 34) had very high levels of circulating sclerostin compared with all others (p < 0.01), whereas sclerostin
correlated negatively with bone specific alkaline phosphatase (a bone formation marker; r 5 20.541, p < 0.0001) and
positively with C-telopeptide of collagen type-1 (a bone resorption marker; r 5 0.524, p < 0.0001). Patients with International
Staging System (ISS)-3 disease had higher circulating sclerostin compared to ISS-1 and ISS-2 MM (p 5 0.001). Furthermore,
patients with high sclerostin (upper quartile, n 5 40) had a median survival of 27 months versus 98 months of all others
(p 5 0.031). Relapsed MM patients had higher levels of circulating sclerostin even compared to newly diagnosed patients
(p < 0.01). Bortezomib monotherapy resulted in a reduction of sclerostin by almost 50% in both responders and
non-responders. These results suggest that patients with active myeloma have elevated circulating sclerostin, which
correlated with advanced disease features including severe bone disease. Our study indicates sclerostin as a possible
target for the development of novel therapies to enhance osteoblast function in myeloma.
Osteolytic bone disease is one of the most common and dev-
astating complications of multiple myeloma (MM). Almost
80% of myeloma patients at baseline have evidence of bone
loss. MM-related bone disease is due to increased osteoclast
activity and reduced osteoblast function. The interactions
between myeloma cells and bone marrow stromal cells lead
to the overproduction of several chemokines and cytokines
that are responsible for this imbalance between osteoclast
and osteoblast activity.1To-date, dickkopf-1 (Dkk-1) is con-
sidered as the main causative factor for the osteoblast exhaus-
tion in MM. Dkk-1 is overproduced by myeloma cells and
inhibits the canonical Wingless and Int-1 (Wnt) signaling,
which is crucial for the osteoblast differentiation and
activity.2,3
Sclerostin is another Wnt inhibitor, specifically expressed
by osteocytes, which inhibits osteoblast-driven bone forma-
tion and induces mature osteoblast apoptosis.4Sclerostin
deficiency leads to the development of rare bone sclerosing
disorders, including sclerosteosis and van Buchem disease.5
However, during the last 2 years it has been reported that
elevated sclerostin is implicated in the mechanisms of bone
loss in metabolic bone diseases, such as postmenopausal
Key words: multiple myeloma, sclerostin, osteoblast, osteocyte,
dickkopf-1, bone disease, bortezomib
The paper has been presented as an oral presentation in ASH 2009
Annual Meeting [Blood 2009;114(22):abstract 425]
E.T. designed the study, performed research, collected data,
analyzed, and interpreted the data, and wrote the paper. M.A.D.
designed the study, performed research, analyzed, and interpreted
the data, and revised the final version of the paper. D.C. performed
research, collected data, performed the statistical analysis, and
revised the final version of the paper. EKat, C.B., M.G., E.M., S.D.,
A.P., J.M., EKas, and K.Z. performed research, collected data, and
revised the final version of the paper.
DOI: 10.1002/ijc.27342
History: Received 10 Jul 2011; Accepted 25 Oct 2011; Online 2 Nov
2011
Correspondence to: Evangelos Terpos, Department of Clinical
Therapeutics, University of Athens School of Medicine, Alexandra
General Hospital, 80 Vas. Sofias Avenue, 11528, Athens, Greece,
Tel: þ30-213-2162846, Fax: þ30-210-3381511, E-mail: eterpos@med.
uoa.gr
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International Journal of Cancer
IJC

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osteoporosis and thalassemia associated osteoporosis.6–8But,
there is no information in the literature for the role of sclero-
stin in MM. Thus, the aim of our study was to evaluate the
circulating levels of sclerostin in MM patients and explore
possible correlations with clinical and laboratory data, includ-
ing the presence of lytic bone disease, the disease stage (we
used the International Staging System-ISS), the biochemical
markers of bone remodeling, and patients’ survival.
Patients and methods
Patients. We evaluated 157 patients with newly diagnosed
symptomatic MM, before the administration of any type of
therapy, including bisphosphonates. Furthermore, 25 patients
with relapsed myeloma, who had participated in another
study of our group for the effect of bortezomib on bone
remodeling,921 patients with monoclonal gammopathy of
undetermined significance (MGUS) and 21 healthy, gender-
and age-matched, individuals who were served as controls,
were also studied. Each control subject was examined to
ensure that there was no evidence of bone disease (i.e., osteo-
porosis, which was excluded using Dual-emission X-ray
absorptiometry (DXA)-scans of the lumbar spine and the
femoral necks or osteoarthritis which was excluded by plain
radiography) and no medication that could alter the normal
bone turnover during the last 6 months.
The study was conducted with Ethical Committee approval
and under the guidelines of the Declaration of Helsinki. All
patients and controls were given informed consent before their
participation in the study.
Measurement of sclerostin and bone indices. Serum was col-
lected within 1 week from the diagnosis in newly diagnosed
myeloma patients and in MGUS patients, on day 1/cycle 1 and
on day 21/cycle 4 of bortezomib therapy in relapsed myeloma
patients and was stored at ?80?C till the day of measurement.
Serum samples were sent on dry ice to the Biomedica Labora-
tory (Wien, Austria) for the measurement of sclerostin with a
sandwich-type ELISA. In summary, microtiter plates were
coated with a polyclonal goat anti-human sclerostin antibody,
incubated over night at 4?C, and blocked at room temperature
for 1 hr. Serial dilutions of recombinant human sclerostin were
used to establish a standard curve, ranging from 0 to 5.4 ng/ml
(240 pmol/l). A secondary monoclonal mouse biotinylated
anti-human sclerostin antibody was used for detection. Twenty
microliter of sample, standard or control were incubated to-
gether with 50 ll of detection antibody over night at room
temperature. After a washing step, 200 ll of horseradish perox-
idase-conjugated streptavidin were added, and the plates were
incubated for 1 hr at room temperature in the dark. After a last
washing step, 3,30,5,50-tetramethyl benzidine was used as sub-
strate and after addition of 50 ll stop solution the optical den-
sity is measured at 450 nm. The detection limit was 0.2 ng/ml
(8.9 pmol/l); the standard range was set from 0.33 to 5.4 ng/ml
(15–240 pmol/l); and the coefficient of variation (CV) for
intra-assay was 4–6% and inter-assay was 5–7%.
We also measured using ELISA methodology the follow-
ing serum indices: (i) Dkk-1 (R&D, Minneapolis, MN), (ii)
C-telopeptide of collagen type-I (CTX; Immunodiagnostic
Systems, Boldon, Tyne & Wear, UK), and (iii) bone-specific
alkaline phosphatase (bALP; Quidel, San Diego, CA), accord-
ing to manufacturers’ instructions. Finally, we evaluated
25(OH) vitamin D using a radioimmunoassay method
(Biosource, Nivelles, Belgium) and parathyroid hormone
(PTH)usinga electro-chemiluminescence
(Roche Diagnostics, Mannheim, Germany), according to
manufacturers’ instructions.
immunoassay
Evaluation of myeloma-related bone disease. Skeletal surveys
using conventional radiography were performed at the time
of diagnosis for newly diagnosed patients or at the time of
initiating bortezomib treatment (at a maximum of 2 weeks
before bortezomib administration) for relapsed patients. A
grading of bone morbidity into three stages according to this
radiographic evaluation was made: group A included patients
with no lytic lesions; group B included patients with 1–3
osteolytic lesions, and group C included patients with more
than three osteolytic lesions and/or a pathological fracture
due to MM. We have used the <3/>3 as cut-off for bone
lesions, as advanced bone disease includes more than three
lytic lesions in the Durie–Salmon staging system.
Statistical analysis. One-way ANOVA was used to test for
differences between the different groups (i.e., patients with
different ISS stages). Bonferroni adjustment was used as a post
hoc test. Wilcoxon Signed Ranks test was used to test for
differences within groups (i.e., patients with refractory
myeloma: comparison of values at baseline versus those of four
cycles of therapy). Pearson’s (r) coefficient of correlation was
used for correlation between variables. Survival probabilities
were calculated by the Kaplan–Meier method and comparisons
made using the log-rank test to identify potential prognostic
factors.
Results
Circulating sclerostin in newly diagnosed MM
Characteristics of patients and controls are depicted in Table 1.
Newly diagnosed, symptomatic MM patients had increased
levels of circulating sclerostin, Dkk-1, and CTX and reduced
levels of bALP compared with MGUS patients and healthy
controls (Table 2/Fig. 1A). There were no differences among
MM patients, MGUS patients, and controls regarding serum
levels of 25(OH) vitamin D and PTH; however, 51 (32.4%)
MM patients had 25(OH) vitamin D deficiency or insuffi-
ciency. Sclerostin values showed strong correlations with
bALP (r ¼ ?0.541, p < 0.001; Fig. 1B), CTX (r ¼ 0.524,
p < 0.001), beta2-microglobulin (r ¼ 0.354, p < 0.001;
Fig. 1C), cystatin-C (r ¼ 0.389, p < 0.001; Fig. 1D), and weak
correlation with Dkk-1 (r ¼ 0.201, p ¼ 0.04). Patients with
advanced bone disease (>3 lytic lesions and/or fractures) had a
borderline increase of sclerostin compared to all others (mean
6 SD: 0.51 6 0.38 ng/ml vs. 0.41 6 0.40 ng/ml, p ¼ 0.078).
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However, patients who presented with fractures at diagnosis
(n ¼ 34) had very high levels of circulating sclerostin
(0.62 6 0.31 ng/ml, p < 0.01) compared with all others.
Patients with ISS-3 disease had higher circulating sclerostin
compared to ISS-1 and ISS-2 MM (mean 6 SD for circulating
sclerostin was: 0.35 6 0.28 ng/ml, 0.39 6 0.28 ng/ml and
0.71 6 0.49 ng/ml, for patients with ISS-1, ISS-2, and ISS-3,
respectively; p ¼ 0.001; Fig. 2A). Patients with Durie–Salmon
stage B (serum creatinine ?2 mg/dl) had elevated circulating
sclerostin (0.92 6 0.72 ng/ml) compared to patients with
stage A (serum creatinine <2 mg/dl; 0.41 6 0.36 ng/ml;
p < 0.001).
Table 2. Mean values of circulating levels of the studied parameters of bone remodeling (6SD) in patients and controls
Parameter
Sclerostin
(ng/ml)
Dkk-1
(pg/ml)
CTX
(ng/ml)
bALP
(U/l)
25(OH)vitD
(ng/ml)
PTH
(pg/ml)
MM at diagnosis 0.48 (60.46)3096 (65240) 0.78 (60.31)16.3 (611.2) 26.7 (610.2) 30.2 (66.1)
MGUS0.26 (60.29)1248 (6798) 0.33 (60.38) 34.8 (616.8)27.9 (68.1) 31.8 (64.2)
Controls 0.31 (60.20)1104 (6280) 0.27 (60.21)29.3 (68.9) 30.1 (69.2) 31.9 (63.7)
p-Value (MM at diagnosis vs. MGUS)0.004
<0.001
<0.001
<0.0010.323 0.786
p-Value (MM at diagnosis vs. controls) 0.01
<0.001
<0.001
<0.001 0.1980.821
Relapsed myeloma0.62 (60.37)5520 (68776) 0.92 (60.52) 14.8 (613.9)24.3 (65.2) 31.6 (62.9)
p-Value (relapsed MM vs. MGUS)
<0.001
<0.001
<0.001
<0.0010.105 0.698
p-Value (relapsed MM vs. controls)
<0.001
<0.001
<0.001
<0.0010.0760.943
Relapsed MM post four-cycles
of bortezomib
0.32 (60.19)2118 (61191) 0.32 (60.24)26.1 (619.7)25.6 (66.5)32.1 (63.2)
p-Value (relapsed MM, pre- vs.
post-bortezomib)
<0.001
<0.001
<0.001
<0.0010.7650.754
Table 1. Characteristics of patients and controls
ParameterSymptomatic MM at diagnosis MGUSControlsRelapsed MM
No157 2121 25
Gender (M/F) 87–7012–912–916–9
Median age (range)68 (36–94) 67 (54–80)68 (50–79) 68 (56–78)
Ig-subtype:
IgG/IgA/BJ/IgD/NS 94–38–21–3–113–7–1–0–0 – 16–6–2–0–1
ISS-stage ISS-1: 56 (35%)6 (24%)1
ISS-2: 51 (32%) 7 (28%)
ISS-3: 50 (32%)12 (48%)
Osteolytic Disease Group A: 34 (21%) ––3 (12%)
Group B: 57 (36%)––7 (28%)
Group C: 66 (42%)––15 (60%)
Hb <10 g/dL52 (33%)––10 (40%)
creatinine >UNL 37 (23%)1 (4%) 2 (9%)8 (32%)
creatinine ?2 mg/dl
albumin <3.5 g/dL
21 (13%)–– 5 (20%)
76 (48%)–– 13 (52%)
b2-M >3 mg/L 98 (62%)–– 19 (76%)
b2-M >6 mg/L48 (30%)––8 (32%)
CRP >10 mg/L31 (20%)–– 7 (28%)
LDH > 240 U/L47 (29%)–– 6 (24%)
Cystatin-C >UNL 79 (50%) 1 (4%) 2 (9%) 18 (72%)
1ISS at diagnosis.
Abbreviations: MM, multiple myeloma; MGUS, monoclonal gammopathy of undetermined significance; M, male; F, female; Ig, immunoglobulin; Hb,
hemoglobin; CRP, C-reactive protein; LDH, lactate dehydrogenase; ISS, International Staging System; NS, non-secretory.
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The median lines of therapies given to these patients were 3
(range: 1–7). Conventional chemotherapy (melphalan and
prednisone or vincristine, adriamycine, and dexamethasone)
had been given to 137/157 (87%) as first line anti-myeloma
therapy, whereas of the other 20 patients, seven had received
bortezomib, adriamycin and dexamethasone, eight TD (thali-
domide, dexamethasone), and five melphalan, dexamethasone,
and thalidomide participating in respective clinical trials.
Thirty-four patients (21%) had received both bortezomib and
an immunomodulatory drug (thalidomide or lenalidomide)
during the course of their disease. High dose melphalan fol-
lowed by autologous stem cell transplantation had been given
to 33/157 (21%) patients.
The median survival of newly diagnosed, symptomatic,
myeloma patients was 48 months and the median follow-up
was 20 months. In the univariate analysis, sclerostin corre-
lated with overall survival: patients with high sclerostin levels
(=0.62 ng/ml, upper quartile, n ¼ 40 patients) had a median
survival of 27 months versus 98 months of all others (p ¼
0.031; Fig. 2B). However, in the multivariate analysis, only
cystatin-C (HR 0.32, 95% CI: 0.11–0.94, p ¼ 0.03) and LDH
(HR 0.5, 95% CI: 0.03–0.65, p ¼ 0.01) had an independent
prognostic value for survival. When cystatin-C was not
included in the model, ISS, LDH, and CTX independently
predicted for survival.
Circulating sclerostin in relapsed MM and the effect of
bortezomib
Patients with relapsed MM had previously received 1–3 lines
of antimyeloma therapies. Patients with relapsed myeloma had
higher levels of circulating sclerostin even compared to newly
diagnosed myeloma patients (p < 0.01; Table 2). All patients
with relapsed disease received four cycles of bortezomib mono-
therapy. Eleven (44%) patients achieved an objective response
after four cycles (two patients achieved a complete response
and nine a partial response). Bortezomib administration
Figure 1. Patients with newly diagnosed symptomatic myeloma had elevated circulating sclerostin compared to patients with MGUS and
healthy controls (1A; see also Tables 1 and 2). Circulating sclerostin correlated with bALP (1B), beta2-microglobulin (1C), and cystatin C (1D).
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produced a significant reduction of sclerostin and Dkk-1,
which was followed by CTX decrease and bALP elevation (Ta-
ble 2). Both responders and non-responders showed similar
median reduction of sclerostin after four cycles of bortezomib
(47% vs. 51%, respectively, p ¼ 0.67).
Discussion
Wnt inhibitors, Dkk-1 and soluble Frizzled-related protein-2
are implicated in osteoblast exhaustion which is present in
MM.2,3,10We show here, for the first time, that another Wnt
inhibitor, sclerostin is also elevated in the serum of patients
with active myeloma. Sclerostin is produced only by osteo-
cytes4after they become embedded into a mineralized matrix
to limit further bone formation by osteoblasts.11Mechanical
loading seems to regulate sclerostin production.12Indeed,
long-term immobilized patients present hypersclerostinemia
associated with reduced bone formation.13In our study, ele-
vated sclerostin correlated with reduced bone formation as
assessed by the strong negative correlation with a sensitive
bone formation marker, bALP. Moreover, its strong positive
correlation with the bone resorption marker CTX supports
the role of sclerostin in the development of bone loss in MM.
Indeed, patients with pathological fractures at diagnosis had
very high circulating sclerostin compared with all others.
This result is in accordance with data in postmenopausal
osteoporosis where sclerostin is elevated7and associated with
bone loss and the development of osteoporotic fractures.6
Moreover, in renal osteodystrophy, sclerostin correlated
negatively with bone formation and number of osteoblast in
biopsies,14whereas in thalassemia-related osteoporosis circu-
lating sclerostin also showed a negative correlation with bone
formation markers.8
In our study, sclerostin correlated with advanced disease
features, including ISS-3, high cystatin-C and inferior survival.
A recent study, which has been reported only in an abstract
form to-date, showed an increased sclerostin expression by a
co-culture system of bone marrow stromal cells and human
myeloma cells in vitro. This overexpression of sclerostin was
responsible for reduced expression of several osteoblastic prod-
ucts, such as bALP, bone sialoprotein II and osteocalcin as well
as for decreased mineralized nodule formation and attenuated
expression of member of the AP-1 transcription factor fam-
ily.15The addition of a neutralizing anti-sclerostin antibody to
the co-culture of stromal with myeloma cells restored the
above parameters, through the intra-nuclear accumulation of
beta-catenin in bone marrow stromal cells. Furthermore, in
that study, sclerostin was also involved in inducing increased
receptor activator of nuclear factor-kappa B ligand and
decreased osteoprotegerin expression in osteoblasts, contribut-
ing to the enhanced osteoclast activity occurring in patients
with MM related bone disease.15Our data support these
in vitro data and suggest that myeloma cells through interac-
tions with bone marrow stromal cells lead to enhanced produc-
tion of sclerostin that contributes to osteoblast dysfunction and
osteoclast activation. Furthermore, another recent study
revealed that the interaction of myeloma cells with osteocytes
triggers osteoclastogenesis through increased osteocyte apopto-
sis and the production of pro-osteoclastogenic cytokines in
active myeloma patients.16Thus, we may hypothesize that
advanced myeloma may lead to higher osteocyte apoptosis
that release sclerostin which can be detected in the serum.
These studies support a significant role of sclerostin in the
development of bone destruction in myeloma.
Normally, Dkk-1 blocks osteoblast differentiation, induces
sclerostin expression and leads to osteocyte death.17In MM,
the overproduction of Dkk-1 by myeloma cells2may also
lead to increased sclerostin expression that further inhibits
osteoblast function. The correlation of Dkk-1 with sclerostin
found in this study, although weak, supports this possibility.
Figure 2. Myeloma patients with ISS-3 disease had elevated
circulating sclerostin compared to patients with ISS-1 ans ISS-2
disease (2A). Patients who had a serum sclerostin of ?0.62 ng/ml
(upper quartile, n ¼ 40 patients) had a median survival of
27 months, while the median survival of all other patients was
98 months (2B).
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Although in MM, sclerostin and Dkk-1 seem to be over-
produced either by myeloma cells directly or by stromal cells
due to interactions between myeloma and stromal cells, in
MGUS the levels of both circulating sclerostin and Dkk-1
were not different compared to controls (p ¼ 0.106 and p ¼
0.602, respectively). Similar levels of circulating Dkk-1 in
MGUS and healthy individuals have been also reported by
our group previously, using another methodology for Dkk-1
measurements.3These results are in accordance with data
supporting that bone formation (assessed by bALP serum
levels) is rather normal in MGUS patients and manages to
balance the increased resorption which is also observed in
MGUS.18It is possible that during myelomagenesis, the nor-
mal function of osteoblasts, present in MGUS, is substituted
by the inhibition of osteoblasts by Wnt inhibitors (Dkk-1,
sclerostin) and other cytokines in MM; this leads to osteo-
blast exhaustion and contributes to the development of my-
eloma-related osteolytic disease. Furthermore, in our study
we found no significant correlation between circulating scle-
rostin and Dkk-1 in MGUS patients; this is possibly because
the changes in the MGUS microenvironment may not be so
significant to be reflected in the circulation.
Bortezomib, even as monotherapy, is effective in patients
with relapsed/refractory myeloma. Bortezomib has strong
anabolic effects on osteoblasts and leads to increased bone
formation1,9and increased bone mineral density in a subset
of patients with relapsed myeloma.19In the present study, we
found that bortezomib reduces circulating sclerostin by
almost 50% in both responders and non-responders. This
may be due to the anti-myeloma effect of bortezomib, due to
its reducing effect on Dkk-1, which enhances sclerostin
expression, or due to an independent effect of bortezomib on
osteocytes. Nevertheless, the reduction of sclerostin by borte-
zomib reveals another mechanism of action of bortezomib in
reversing osteoblast dysfunction in myeloma.
We conclude that our study provides evidence that sclero-
stin participates in the myeloma-related bone destruction and
especially in the inhibition of bone formation, which leads to
severe bone disease in patients with active myeloma. These
results reveal sclerostin as a possible target for the enhance-
ment of osteoblast function in myeloma, as has been previ-
ously described in post-menopausal osteoporosis.20Phase 1
studies with anti-sclerostin antibodies have been already
started in myeloma and their results are highly anticipated.
References
1. Christoulas D, Terpos E, Dimopoulos MA.
Pathogenesis and management of myeloma bone
disease. Expert Rev Hematol 2009;2:385–98.
Tian E, Zhan F, Walker R, Rasmussen E, Ma Y,
Barlogie B, Shaughnessy JD, Jr. The role of the
Wnt-signaling antagonist DKK1 in the
development of osteolytic lesions in multiple
myeloma. N Engl J Med 2003;349:2483–94.
Politou MC, Heath DJ, Rahemtulla A, Szydlo R,
Anagnostopoulos A, Dimopoulos MA, Croucher
PI, Terpos E. Serum concentrations of Dickkopf-
1 protein are increased in patients with multiple
myeloma and reduced after autologous stem cell
transplantation. Int J Cancer 2006;119:1728–31.
Moester MJ, Papapoulos SE, Lo ¨wik CW, van
Bezooijen RL. Sclerostin: current knowledge and
future perspectives. Calcif Tissue Int 2010;87:
99–107.
Loots GG, Kneissel M, Keller H, Baptist M,
Chang J, Collette NM, Ovcharenko D, Plajzer-
Frick I, Rubin EM. Genomic deletion of a long-
range bone enhancer misregulates sclerostin in
Van Buchem disease. Genome Res 2005;15:
928–35.
D’Amelio P, Roato I, D’Amico L, Veneziano L,
Suman E, Sassi F, Bisignano G, Ferracini R,
Gargiulo G, Castoldi F, Pescarmona GP, Isaia
GC. Bone and bone marrow pro-osteoclastogenic
cytokines are up-regulated in osteoporosis
fragility fractures. Osteoporos Int, 2011;22:
2869–77.
Polyzos SA, Anastasilakis AD, Bratengeier C,
Woloszczuk W, Papatheodorou A, Terpos E.
Serum sclerostin levels positively correlate with
lumbar spinal bone mineral density in
postmenopausal women – the six-month effect of
risedronate and teriparatide. Osteoporos Int, in
press.
Voskaridou E, Christoulas D, Papatheodorou A,
Bratengeier C, Plata E, Kaliontzi D, Woloszczuk
2.
3.
4.
5.
6.
7.
8.
W, Terpos E. High circulating levels of sclerostin
correlate with bone mineral density in patients
with thalassemia and osteoporosis: the role of the
Wnt signaling in the pathogenesis of bone loss in
thalassemia. Blood 2010;116:691 (abstract 1010).
Terpos E, Heath DJ, Rahemtulla A, Zervas K,
Chantry A, Anagnostopoulos A, Pouli A,
Katodritou E, Verrou E, Vervessou EC,
Dimopoulos MA, Croucher PI. Bortezomib
reduces serum dickkopf-1 and receptor activator
of nuclear factor-kappaB ligand concentrations
and normalises indices of bone remodelling in
patients with relapsed multiple myeloma. Br J
Haematol 2006;135:688–92.
10. Oshima T, Abe M, Asano J, Hara T, Kitazoe K,
Sekimoto E, Tanaka Y, Shibata H, Hashimoto T,
Ozaki S, Kido S, Inoue D, et al. Myeloma cells
suppress bone formation by secreting a soluble
Wnt inhibitor, sFRP-2. Blood 2005;106:3160–5.
11. Poole KE, van Bezooijen RL, Loveridge N,
Hamersma H, Papapoulos SE, Lo ¨wik CW, Reeve
J. Sclerostin is a delayed secreted product of
osteocytes that inhibits bone formation. FASEB J
2005;19:1842–4.
12. van Oers RF, van Rietbergen B, Ito K, Hilbers
PA, Huiskes R. A sclerostin-based theory for
strain-induced bone formation. Biomech Model
Mechanobiol 2011;10:663–70.
13. Gaudio A, Pennisi P, Bratengeier C, Torrisi V,
Lindner B, Mangiafico RA, Pulvirenti I, Hawa G,
Tringali G, Fiore CE. Increased sclerostin serum
levels associated with bone formation and
resorption markers in patients with immobilization-
induced bone loss. J Clin Endocrinol Metab 2010;95:
2248–53.
14. Cejka D, Herberth J, Branscum AJ, Fardo DW,
Monier-Faugere MC, Diarra D, Haas M,
Malluche HH. Sclerostin and dickkopf-1 in renal
osteodystrophy. Clin J Am Soc Nephrol 2011;6:
877–82.
9.
15. Colucci S, Brunetti G, Oranger A, Mori G, Sardone
F, Liso V, Curci P, Miccolis RM, Rinaldi E, Specchia
G, Passeri G, Zallone A, et al. Myeloma cells induce
osteoblast suppression through sclerostin
secretion. Blood 2010;116:1221 (abstract 2961).
16. Giuliani N, Storti P, Abeltino M, Bolzoni M,
Ferretti M, Laziaretti M, Palma BD, Todoerti K,
Martella E, Agnelli L, Neri A, Rizzoli V, et al. In
vitro and in vivo evidences of osteocyte
involvement in myeloma-induced osteolysis.
Blood 2010;116:62–3 (abstract 131).
17. Heiland GR, Zwerina K, Baum W, Kireva T,
Distler JH, Grisanti M, Asuncion F, Li X,
Ominsky M, Richards W, Schett G, Zwerina J.
Neutralisation of Dkk-1 protects from systemic
bone loss during inflammation and reduces
sclerostin expression. Ann Rheum Dis 2010;69:
2152–9.
18. Politou M, Terpos E, Anagnostopoulos A, Szydlo
R, Laffan M, Layton M, Apperley JF, Dimopoulos
MA, Rahemtulla A. Role of receptor activator of
nuclear factor-kappa B ligand (RANKL),
osteoprotegerin and macrophage protein 1-alpha
(MIP-1a) in monoclonal gammopathy
of undetermined significance
(MGUS). Br J Haematol 2004;126:686–9.
19. Terpos E, Christoulas D, Kokkoris P, Anargyrou
K, Gavriatopoulou M, Migkou M, Tsionos K,
Dimopoulos MA. Increased bone mineral density
in a subset of patients with relapsed multiple
myeloma who received the combination of
bortezomib, dexamethasone and zoledronic acid.
Ann Oncol 2010;21:1561–2.
20. Ominsky MS, Li C, Li X, Tan HL, Lee E,
Barrero M, Asuncion FJ, Dwyer D, Han CY,
Vlasseros F, Samadfam R, Jolette J, et al.
Inhibition of sclerostin by monoclonal antibody
enhances bone healing and improves bone
density and strength of non-fractured
bones. J Bone Miner Res 2011;26:1012–21.
Short Report
Terpos et al.
1471
Int. J. Cancer: 131, 1466–1471 (2012) V
C 2011 UICC