Haematologica 2003 - Supplements

most relevant clinical and biological characteristics as well as the
S-phase assessed by flow cytometry were also analysed.
Results: Chromosomal imbalances were identified by CGH
analysis in 60 out of the 90 cases (67%). A total of 320 changes
were identified by CGH with a median of 4 changes per case
(range: 1-28). Gains of chromosomal material were more
frequent than losses (224 gains vs 96 losses). The most frequent
aberrations among the cases with genomic changes were gains on
chromosome regions 1q (44%), 9q (27%), 15q (25%), 11q (24%),
5q (24%), and 3q (18%), while losses mainly involved
chromosomes 13 (44%), 16q (18%), 8p (11%) and 6q (9%).
Interestingly the most frequent losses (13q-, 16q- and 8p-) were
associated each other (p=0.008). In a similar way, gains on
different chromosomes, leaving out 1q, tended to be present
together. Thus, cases with gains on 1q displayed a significantly
higher incidence of losses on 13q, 6q and 16q (p=0.03), but not of
gains of other chromosomes. The clinical variables influencing
negatively survival were: age > 70 (p 6 mg/L (p=0.02), calcium > 11.5 mg/dL (p=0.001), creatinine >
2 mg/dL (p=0.004), ECOG > 2 (p=0.01), and number of plasma
cell in S-phase > 1.5% (p=0.001). Patients with losses on 13q and
gains on 3q and 11q assessed by CGH had a significantly worse
overall survival compared with patients without these
abnormalities (p= 0.03, p=0.04 and p=0.02 respectively). The rest
of genomic changes did not confer an adverse prognosis.
Conclusions: CGH detects a high incidence of chromosomal
gains and losses in MM. Gains on 1q, 9q and 15q as well as
losses on chromosomes 13 and 16q were the most frequent
genomic changes. Losses on 13q and gains on 3q and 11q
determined by CGH were associated with a shorter survival.
(Supported by Grants from Spanish FIS 01/1161 & G03/136)
050
Cyclin D1 overexpression has no effect on survival in
myeloma while upregulation of MM-SET may confer a
favourable prognostic effect.
Ho PJ, Tay C, Sze DMY, Jeffels MJ, Brown RD, Gibson J,
Joshua DE
Institute of Haematology and Centenary Institute, Royal Prince
Alfred Hospital, Sydney, Australia.
Translocations involving chromosome 14q32 are amongst the
most common genetic abnormalities in myeloma, occurring in up
to 80% of cases. Despite the frequency of occurrence, their
pathogenic significance is not yet clear. The most frequent
translocations involve chromosomes 11q13, 4p16 and 16q32. We
examined the expression of 2 candidate oncogenes on
chromosomes 11q and 4p, Cyclin D1 (CND1) and MM-SET
respectively, in purified myeloma plasma cell (MPC)
populations, using real-time RT-PCR with β-actin as internal
control, Sybr Green I as fluorophore and a series of standards
containing 10 3 – 10 7 cDNA copies. PCs were purified on the
basis of CD38hi and CD138 expression by flow sorting. CND1
was quantitated in 18 MPC populations, with CND1: β-actin
cDNA ratios ranging from 0.01 to 314. CND1 is not expressed in
normal PCs (CND1: β-actin ≈ 0). In 11/18 samples, CND1: β-
actin was 0.01-1.4, while 7 samples demonstrated increased ratios
of 6.2 to 314, indicating CND1 overexpression. There was no
significant difference between the 2 groups in survival, β 2
microglobulin (4.2 and 6.0 mg/L respectively, normal range 0–
2.4mg/L) or mean PC labelling index (PCLI) (5.0% and 5.8%
respectively, normal range 0–4% measured by flow cytometry).
The correlation between CND1 expression and FISH detection of
t(11;14) has been confirmed in 9 samples. The t(4;14)
translocation was detected by nested RT-PCR for “hybrid” cDNA
containing IgH and the candidate oncogene MM-SET, using
myeloma cell lines carrying t(4;14) as internal controls. Of 32
samples examined, 7 were positive. Survival of the 2 groups also
showed no significant difference. In a separate group of 12
patients, MPCs were examined for MM-SET expression using
real-time RT-PCR. MM-SET: β-actin cDNA ratios ranged from
0.1 to 22. MM-SET expression has also been reported to be low
or undetectable in normal PCs. Eight of the 12 MPCs examined
showed MMSET: β-actin ratios of 0 to 1.6. The other 4 samples
demonstrated higher ratios of 9 to 22, indicating increased MM-
SET expression. Survival of these 4 patients appeared to be
superior compared with the other 8 patients, although not
significant due to small sample size. The mean PCLI of the 2
groups with low and high MMSET expression were 2.4% and
7.4% respectively (normal range 0–4%). In summary, expression
analysis of candidate genes in chromosome 14q32 translocations
in purified MPCs has shown no effect of CND1 overexpression
on survival, while a possible favourable prognostic effect of MM-
SET upregulation will be further examined in a larger cohort.
051
Frequency and prognostic relevance of t(4;14) in
previously untreated Multiple Myeloma (MM) patients
receiving either single or double autotransplants.
Carolina Terragna, Michele Cavo, Simona Soverini,
Claudia Cellini, Nicoletta Testoni, Antonello De Vivo,
Marilina Amabile, Barbara Giannini, Emanuela Ottaviani,
Tiziana Grafone, Elena Zamagni, Patrizia Tosi, Delia
Cangini, Paola Tocchetti, Sante Tura, Michele Baccarani
and Giovanni Martinelli.
Institute of Hematology and Medical Oncology "Seràgnoli" -
University of Bologna
In patients with MM a number of recurrent translocations
involving chromosome 14 at band q32 have been recently
identified, the most common being the t(11;14) and the t(4;14).
Both these chromosomal abnormalities are closely associated
with particular presenting features of the disease and may help to
identify patients at different risk of death. In particular, the
t(11;14) predicts for good prognosis, whereas the t(4;14) has been
reported to be an unfavorable prognostic feature. The t(4;14) has
been described almost exclusively in MM patients, although its
exact role in the pathogenesis of the disease has not fully
elucidated. The translocation affects at least two potential
oncogenes, MMSET on der(4) and Fibroblast Growth Factor
Receptor 3 (FGFR3) on der (14); the role of two additional genes
(TACC3 and LETM1) located near the breakpoint region on
chromosome 4 has not yet been evaluated.
In the present study we investigated the frequency and the
prognostic relevance of the t(4;14) in a series of 63 patients with
de novo MM, who were randomized to receive either a single
(Tx-1) or a double (Tx-2) autotransplant as primary therapy for
their disease. For this purpose we analyzed (1) the presence of
t(4;14) by RT-PCR of the hybrid transcript between MMSET and
the IgH locus; (2) the overexpression of FGFR3 by Real-time
RT-PCR; (3) the frequency of potentially activating point
mutations in the FGFR3 translocated coding region, by direct
sequencing of RT-PCR products; 4) the relationship between
t(4;14), response to high-dose therapy and outcome of
autotransplant(s).
Overall, the t(4;14) was detected in 17/63 patients (27%), a value
slightly higher than that reported by others. 13/17 patients had
both MMSET/IgH fusion gene and FGFR3 overexpression, while
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