Download Linfoma di Burkitt (L-B)

Linfoma di Burkitt
(Burkitt)
Aims
….Attitudes are more
important than abilities
Motives are more
important than methods
Character is more
important than cleverness
And heart takes precedence
over the head…..
Denis P. Burkitt, 1991
LINFOMA DI BURKITT (LBT)
endemico:
zone centrali dell’Africa (malaria)
età pediatrica; sedi: mandibola,
ovaio
sporadico:
paesi occidentali
età variabile; sedi: intestino,
gonadi, SNC
HIV-correlato: SNC, etc.
Buona risposta in età pediatrica con terapie aggressive
FORMA ENDEMICA
(Lancet Oncology 2004; 5:738-46)
Patogenesi del linfoma di Burkitt endemico
legata alla cooperazione di:
- EBV (immortalizzazione),
- malaria (spinta proliferativa),
- Arbovirus trasmessi da mosche (stimolo
immunitario),
- Euphorbia tirucalli (danno al DNA),
- traslocazione coinvolgente c-MYC.
LINFOMA DI BURKITT
MORFOLOGIA:
endemico/sporadico= isomorfi
taglia media omogenea
cromatina reticolare
2-6 nucleoli
citoplasma basofilo/vacuolato
crescita coesiva
mitosi numerosissime
aspetto a cielo stellato
LBT: dettagli citologici
in un caso con colonizzazione “follicolare”
LINFOMA DI BURKITT
FENOTIPO:
SIgM+
marcatori B+
CD10+
Bcl-6+
Bcl-2c-myc+
Mib-1+ = 100%
CD10
Bcl-6
Bcl-2
Ki-67
MIB1
GENOTIPO
LBT endemico:
EBV+
t(8;14)
LBT sporadico :
EBV+: 25% HIV50% HIV+
t (2;8)
t(8;22)
diversi breakpoints
p53 (?)
p21 (?)
Sul cromosoma 8: gene c-MYC
BURKITT LYMPHOMA IN UGANDA IN THE THIRD MILLENNIUM:
A MORPHOLOGIC AND MOLECULAR APPRAISAL ON TISSUE
MICRO-ARRAY
Cristina Campidelli, Lynnette Tumwine, Pier Paolo Piccaluga,
Stefano A Pileri
Hum. Pathol., 39:817-823, 2008.
HIV infection and c-MYC status in endemic Burkitt lymphoma
Campidelli, C., Gazzola, A., Vitone, F., Tumwine, L., and Pileri, S.A.
Hum. Pathol., 39:1408-9, 2008.
Patient and material collection
•
95 cases from Ugandan tribes
•
2-64 ys (median age: 16)
•
Site of involvement:
- lymph node (34 cases)
- abdomen
(26 cases)
- gonads
(25 cases)
- jaw
(10 cases)
•
formalin fixed paraffin embedded blocks punched
and collected in 2 TMA blocks (48 and 47 cases
each)
TMA technology
Results
• Positivity for B-cell markers, CD10 and Bcl-6
• Negativity for Bcl-2
• Ki-67 close to 100%
• Thirty-five CD30+ cases (37%)
• Expression of CD38 in 73 cases (77%) and CD138 in 43
cases (45%)
• IRF-4 mostly negative (7 positive cases)
• Constant EBV integration
CD30
CD138
EBER
HIV-status
• None of the samples showed HIV integration
• HIV-1 DNA was investigated by:
RT-PCR amplifying gag region (142 bp)
nested PCR amplifying env region (248 bp)
Driver GA et al. J Virol Methods, 2007
Brachtel EF et al. AIDS Res Hum Retroviruses, 2002
Strappe PM et al. J Virol Methods, 1998
FISH analysis
• FISH failed to demonstrate t(8;14) due to DNA degradation
• Surrogated by immunohistochemistry
• Characteristic expression patterns of TCL1, CD38, and
CD44 identify aggressive lymphomas harboring a MYC
translocation (Rodig SJ, Am J Surg Pathol, 2008)
• 64 out of 85 cases were TCL1+, CD38+ and CD44• 9 out of 85 cases were TCL1-, CD38+ and CD44• 9 out of 85 cases were TCL1+, CD38- and CD44• 3 out of 85 cases were TCL1-, CD38- and CD44-
TCL1
CD38
CD44
Question
• Are the three subtypes of Burkitt
lymphoma different diseases or different
features of the same disease?
Piccaluga PP, De Falco G, Kustagi K,
Gazzola A, Astolfi A, Agostinelli C,
Leucci E, Onnis A, Tripodio C,
Sapienza MR, Bellan C, Lazzi S,
Tumwine L, Mawanda M, Ogwang M,
Calbi V, Formica S, Califano A, Pileri
SA and Leoncini L: Gene expression
analysis uncovers similarity and
differences among Burkitt lymphoma
subtypes. Blood 2011, E-pub ahead of
print.
Molecular profiling of
BL subtypes
BL is a unique molecular
entity
Burkitt lymphoma
Follicular lymphoma
Diffuse large B-cell lymphoma
Primary mediastinal B-cell lymphoma
Chronic lymphocytic leukemia
Normal B-cells
BL subtypes are all related to GC cells & presents
several deregulated genes and cellular programs
1,000 genes
Naï
Naïve
Germinal center B -cells
Naive
Memory
Germinal
center B cells
BL
Memory
BL
N/M
N/M
GC
GC
-1
+1
Grey zone
SPARC
• immune response
• proliferation (MYC)
• adhesion
• NOTCH signaling
BL
Germinal Center B cells
Though similar, BL subtypes present
differences in their GEPs
eBL
sBL
HIV-BL
HIV BL
eBL
eBL
HIV-BL
HIV
- BL
sBL
sBL
Though similar, BL subtypes present
differences in their GEPs
eBL
HIV-BL
eBL and HIV-BL: 16 genes
(almost identical),
eBL
sBL
eBL & sBL: 254 genes, including
cell cycle regulation.
eBL (TAT & HIV-BL)
GSEA showed that eBL and sBL differ for the
expression of genes related to the RBL2 network
eBL
sBL
Accordingly, RBL2 malfunction is relevant for eBL but doesn’t affect sBL.
RBL2 functional network identified by
ARACNe
The results do not vary by
subtracting the MYC network
Conclusions
1. Irrespective of the subtypes, BL is a unique molecular
entity distinct from other B-NHLs.
2. All BL subtypes are related to GC B-cells.
3. Genes and cellular programs deregulated in BL have
been identified, including cell cycle and proliferation
control, NOTCH signaling and immune response.
4. GEP differences do exist among BL subtypes.
5. In particular, RBL2 malfunction seems to characterize
the signature of eBL (and HIV-BL?) suggesting a
possible involvement of such gene in BL pathogenesis.