Expression of CD 81 in multiple myeloma. CD81 could be a predictive marker for disease progression.

1. 1
Shivali Jasrotia
AIIMS
23 April 2012

2. Correspondence:
Professor J-F San Miguel, Servicio de Hematologı´a, Hospital Universitario de Salamanca, Paseo de San
Vicente 58-182, 37007 Salamanca, Spain.
Leukemia advance online publication, 9 March 2012; doi:10.1038/leu.2012.42
2

3. Introduction
Multiple Myeloma
B-cell malignancy characterised by abnormal proliferation of
plasma cells.
Myeloma cells produce abnormal immunoglobulin.
 Overproduce monoclonal protein or paraprotein (>30g/L blood
serum) (IgG > IgA)
Clinical manifestations:
 Anaemia – 73%
 Bone lesions – 58%
 Renal insufficiency – 48%
 Hypercalcemia- 28%
 Weight loss – 24%, one-half of whom had lost ≥ 9 kg
3

4. Anderson K et al, Annu. Rev. Med. 2011. 6
Origin of multiple myeloma cells
4

5. 2nd most common hematological malignancy
Incidence and rates
 1% of all cancers
 10- 15% of all hematological malignancies
 20% deaths related to hematological malignancies
Median age: 62 yrs (men) and 61 yrs (women)
Occurrence is more common in men than women (1.6:1)
Median survival:
 After conventional therapy: 3- 4 yrs
 After HD treatment followed by Auto SCT: 5- 7 yrs
MM: Epidemiology
Raab M. et al, Lancet 2009; 374: 324–395

6. Sirohi B. et al, Lancet 2004; 363 & Anderson K et al, Annu. Rev. Med. 2011. 6
Diagnostic criteria for MGUS, SMM, and MM
MM: Multistep development model
Annual rate of transformation
MM
MMMGUS
SMM
1 %
10 %
6

7. 8
MM: Risk Stratification of myeloma using FISH and Karyotyping
A. Standard-risk
1. Hyperdiploidy
2. t(11;14)
3. t(6;14)
B. High-risk
1. 17p deletion
2. t(4;14)
3. t(14;16)
4. t(14;20)
5. Deletion 13 or hypodiploidy by conventional karyotyping
Rajkumar S V. Am J Hematol 2011;86(1):57–65

8. 9
CD81 or TAPA- 1 or Tetraspanin-28
CD81 is transmembrane pore integral
glycoprotein.
It forms a signal transduction complex
with CD19, CD21 and CD225 (B-cell co-
receptor complex) on the surface of
the mature B cell.
CD81 is necessary for normal CD19
expression although the mechanisms
are still unclear.
Advances in Imm., Vol 111
edited by Frederick W. Alt

9. 10
Purpose of the Study
1. Analyse the frequency and prognostic impact of CD81 using
immunophenotyping.
2. Investigate whether CD81 could be a predictive marker for disease
progression.
3. Evaluate the expression of CD81 at the transcriptome and protein
level.

10. Patients and Methods
a. 230 newly diagnosed, symptomatic, elderly MM treated patients.
b. A validation set based on 325 newly diagnosed, symptomatic, transplant
patients.
c. 56 SMM patients newly diagnosed and with high-risk of progression to
symptomatic disease.
d. Median follow-up was 32 and 22 months for the MM and SMM series
All control and patient samples were collected after informed consent was obtained
from each individual.
Treatment protocol:
According to Spanish GEM05>65yrs
BMP or BTP (six cycles for each arm) followed by maintenance with either BT or BP for
up to 3 yrs.
Patients

11. Statistical Analysis
The Mann-Whitney U and Correlation tests were used to estimate the
statistical significance of differences between groups of cases and correlations
between variables, respectively.
KM method used to plot time to progression, progression-free survival (PFS)
and overall survival (OS) distribution curves.
The Cox regression proportional hazard model was used in a multivariate
analysis of PFS and OS.
For all statistical analyses SPSS software v15.0 was used.
Patients and Methods

12. Patients and Methods
Methods
Immunophenotyping: MFC using three four- color mAb combinations.
FISH: Performed at baseline in 211 of 230 patients and patients are classified
for risk stratification.
GEP: To investigate the correlation b/w CD81 surface protein and its
expressions.
Cell Culture and western blotting: To validate the amount of CD81 protein
expression in a panel of MM cell lines.

13. 14
230 pts enrolled
23 for GEP
207 pts
103 out of 230 (45%)
CD81+ MM-PC
74/103
Heterogeneous
CD81-/+
expression
29/103
Homogeneous
CD81+
expression
92 CD81-
Results
Frequency of CD81 antigen expression and relationship with disease characteristics

14. Heterogeneous
CD81-/+
expression
Homogeneous
CD81+
expression
CD81-
expression
Bivariate dot plot histograms illustrating
the patterns of CD81 vs CD19 expression in
MM-PCs and normal PCs.
15
74/103
29/103
Patterns of CD81
expression on normal PC
Results

15. 16
CD81 expression in MM cell lines
Results
5/13 cell lines
homogeneously
positive

16. 17
Genomic vs antigen CD81 mRNA expression
in MM (n=23)
Results

17. 18
Impact of
CD81 antigen
expression on
patients’
survival
Results

18. 19
Results
Time to progression of SMM patients
grouped according to the presence of:
CD81+ (n=32) or
CD81- (n=24) MM-PC.

19. 20
Results
Baseline disease features with a significant effect on PFS and/or OS (univariate and multivariate analyses) of
newly diagnosed elderly myeloma patients included in the GEM2005>65year trial

20. 21
Results
Baseline disease features with a significant effect on PFS and/or OS (univariate and multivariate analyses) of
newly diagnosed elderly myeloma patients included in the GEM2005>65year trial

21. 22
Results
Impact of CD81 antigen expression on survival of standard and high-risk symptomatic patients.

22. 23
Discussion
CD19 expression is an adverse prognostic marker but low frequency (4%) hampered
the its impact.
The frequency and prognostic impact of CD81 was analyzed using MFC in treated
patients and further validated in transplanted patients.
CD81+ MM-PC is present in approximately half of all myeloma patients.
Positive expression for CD81 in 40% of MM cell lines, which was further confirmed by
western blotting.
At transcriptome and protein level, CD81 showed significant correlation between the
phenotypic and GEP results.

23. 24
Discussion
By multivariate analysis, CD81+ MM-PC plus high-risk cytogenetic at diagnosis
represented the best combination of independent variables for predicting both PFS and
OS.
Found that CD81+ SMM patients had a shorter time to progression to symptomatic
disease than CD81- patients.
Importantly, the expression of CD81 in MM-PCs is an independent prognostic factor for
patients with symptomatic MM and a marker for risk of progression in SMM.
Thus, the current findings shows the existence of a phenotypic-genomic correlation of
CD81 expression in patients with myeloma

24. 25
Conclusion
There are still several subgroups defined by cytogenetics, and that other techniques
such as MFC or GEP may contribute to improve patient risk stratification.
Further investigations on the clinical value of CD81 assessment are warranted in the
context of low-risk SM and MGUS patients.
And, the prognostic influence of CD81 expression makes this marker a potential
therapeutic target.
Thus, the precise mechanism of CD81 activation of MM-PCs deserves further
investigations.

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