Haematologica, Vol 92, Issue 4, 566-567 doi:10.3324/haematol.10767
Copyright © 2007 by Ferrata Storti Foundation

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Piccaluga, P. P. Articles by Pileri, S. A. Search for Related Content PubMed PubMed Citation Articles by Piccaluga, P. P. Articles by Pileri, S. A.

Malignant Lymphomas

Expression of CD52 in peripheral T-cell lymphoma

Pier Paolo Piccaluga^*, Claudio Agostinelli^*, Simona Righi, Pier Luigi Zinzani, Stefano A. Pileri

Institute of Hematology and Medical Oncology "L. and A. Seràgnoli", S. Orsola-Malpighi Hospital, University of Bologna, 40138 Bologna, Italy

Correspondence: Stefano A. Pileri, MD, Chair of Pathology, Institute of Hematology and Medical Oncology "L. and A. Seràgnoli", Hematopathology Unit, St. Orsola-Malpighi Hospital, University of Bologna, via Massarenti 9, 40138 Bologna, Italy. Phone: international +39.051.6364034. Fax: international +39.051.6364037. E-mail: pileri{at}med.unibo.it

TOP ABSTRACT References

 
Peripheral T-cell lymphoma unspecified (PTCL/U) is a rare tumor characterized by poor treatment response and a dismal prognosis. We studied CD52 expression in 97 PTCL/U cases by immunohistochemistry on tissue-microarrays. Furthermore, CD52 gene expression was studied in 28 cases for which RNA was available. We found that CD52 is expressed in approximately 40% of PTCLs/U at the same level as in normal T-lymphocytes. Although other factors may play a role in the in vivo response to alemtuzumab, an anti-CD52 monoclonal antibody, the estimation of CD52 expression may provide a rationale for the selection of patients with a higher probability of treatment response.

Key words: T-cell lymphoma, CD52 expression.

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of tumors that the WHO classification basically subdivides into specified and unspecified (U).¹ In Western countries, they correspond to 15% of non-Hodgkin’s lymphomas,¹ and more often present in advanced stage in middle aged/elderly patients who die rapidly despite aggressive therapies.² Recently, novel clinical/pathological scores have been proposed to improve prognostic stratification of PTCL/U patients.^3,4 However, novel targeted therapies are needed.

CDw52, originally characterized as a human leukocyte differentiation antigen, is present on the surface of most peripheral blood lymphocytes, macrophages, and monocytes at relatively high density. It is absent from myeloid cells, platelets, and erythroid cells as well as hematopoietic stem cells.⁵ Campath-1H (alemtuzumab) is a humanized antibody against CD52 currently approved for chronic lymphocytic leukemia (CLL) therapy.⁶ Furthermore, anti-CD52 showed interesting activity in T-prolymphocytic leukemia (disease characterized by high CD52 expression) and cutaneous T-cell lymphomas.⁷ Only some data are available regarding alemtuzumab in PTCL/U,^7,8 which is often characterized by an aberrant lack of surface antigens.⁴ Although other factors can affect the response to alemtuzumab in vivo, it is conceivable that lack of CD52 expression may play a major role in determining refractoriness to the compound. The aim of this study was to examine CD52 expression in PTCL/U to evaluate the potential for a more rationale use of alemtuzumab in this highly aggressive disorder.

We studied the expression of CD52 on tissue microarrays (TMAs) from 148 PTCL/U cases.⁴ Ninety-seven out of 148 cases turned were evaluable due to core loss following repeated cutting. In addition, frozen material was available from 28 cases and gene expression profiles (GEP) were generated and compared to that of 20 samples of normal T-lymphocytes. These had been collected from peripheral blood and reactive tonsils of healthy donors.⁹ In order to avoid the confusing effect of reactive components, only cases with 70–90% of neoplastic elements were chosen for GEP-analysis. GEP were generated and analyzed as previously reported⁹ by using the HG-U133 2.0 plus microarrays (Affymetrix, Inc. http://www.affymetrix.com/support/index.affx). All patients had given permission for use of samples for research and study approval was obtained from the Local Ethical Committee.

Anti-CD52 (rat anti-human, monoclonal; Serotec ltd, Oxford, UK) was applied at a 1:200 dilution on a TechMate 500 immunostainer and revealed by the EnVision+ technique.⁴ Before immunohistochemistry, the sections underwent antigen retrieval in citrate buffer (pH=6.0) in a micro-waver at 900W (3 cycles lasting 5' each). The TMAs were scored by two experienced pathologists, who estimated the number of positive cells. Cores were considered positive if 30% or more of the tumor cells were stained.⁴

We found that overall CD52 was down-regulated in PTCL/U when compared with normal T-lymphocytes (T-test, p<0.0000001). In particular, in 17/28 PTCL/U (60%), CD52 expression level was below the lowest value recorded in normal T-cells (Figure 1). In addition, it was detected by immunohistochemistry in 40 out of the 97 (41%) evaluable PTCLs. Notably, GEP paralleled CD52 staining in those cases undergoing both molecular analysis and immunohistochemistry. In particular, the median gene expression level was 5,031.00 compared with 1,804.00 in cases CD52⁺ and CD52^– at immunohistochemistry respectively (p<0.05). Interestingly, all the samples of normal T-lymphocytes, representing the supposed normal counterparts of this tumor, were CD52 positive, suggesting that PTCL/U often lacks its expression at both the RNA and protein level. This is not surprising as we found CD2, CD3, CD4, CD5, CD7, and CD8 variably expressed.⁴ In other words, defectivity of T-cell associated antigens seems to be a hallmark of neoplastic transformation. It is of note, that our results, referring for the first time to paraffin-embedded cases, are in line with the those previously reported on frozen material.¹⁰ Interestingly, our data seem to be in keeping with the clinical results obtained by Enblad et al.,⁸ who found an overall response rate of 36% in PTCL treated with alemtuzumab.

View larger version (81K): [in this window] [in a new window] [Download PPT slide]

Figure 1. CD52 expression in PTCL/U. A. CD52 expression in peripheral T-cell lymphoma unspecified (PTCL/U) evaluated by gene expression analysis and immunohistochemistry as percentage of positive cases. B. CD52 gene expression in PTCL/U and normal T-cells. Raw expression data are reported on y axis. C. PTCL/U: neoplastic cells are negative at CD52 determination. Note the internal control represented by scattered reactive T-lymphocytes, which are clearly distinct from neoplastic elements due to both normal T-cell antigen expression and lack of cytological atipia. (Immunoperoxidase Envision+ Technique; Gill’s hematoxylin counterstaining; x200). D. PTCL/U: neoplastic cells infiltrating a normal germinal center (GC) strongly express CD52. Note the negativity of residual elements of the mantle zone (MZ) (Immunoperoxidase Envision+ Technique; Gill’s hematoxylin counterstaining; x200). Inset: Neoplastic cells show overt nuclear shape and size variability and high nuclear/cytoplasmic ratio (Immunoperoxidase Envision+ Technique; Gill’s hematoxylin counterstaining; x600).

Based on the above mentioned findings, the estimation of CD52 expression may provide a rationale for the selection of patients with a higher probability of responding to alemtuzumab by avoiding the risk of unwanted toxicity. Certainly, this implies standardization of the techniques adopted for CD52 evaluation. In our opinion, immunohistochemistry seems to represent an optimal approach. It can be applied to routine material in phase of other proteomic techniques, such as flow citometry or western blot. In fact, such techniques require fresh material that is only available in a small minority of lymphoma patients. This deserves further evaluation within prospective clinical trials.

 
^* These authors equally contributed to this work.

Addendum: after the acceptance of the present manuscript, similar immunohistochemical findings were reported by Rodig et al., cited in ref. #¹¹.

Funding: this work was supported by BolognAIL, AIRC, FIRB/RFO (Proff Pileri and Zinzani), Fondazione Cassa di Risparmio in Bologna, Fondazione della Banca del Monte e Ravenna.

TOP ABSTRACT References

 

1. Jaffe ES, Ralfkiaer E. Jaffe ES, Harris NL, Stein H, Vardiman JW, ed. Tumours of haematopoietic and lymphoid tissue, Lyon: IARC Press. 2001. p. 191-4.
2. Jantunen E, Wiklund T, Juvonen E, Putkonen M, Lehtinen T, Kuittinen O, et al. Autologous stem cell transplantation in adult patients with peripheral T-cell lymphoma: a nation-wide survey. Bone Marrow Transplant 2004;33:405-10.[CrossRef][Web of Science][Medline]
3. Gallamini A, Stelitano C, Calvi R, Bellei M, Mattei D, Vitolo U, et al. Peripheral T-cell lymphoma unspecified (PTCL-U): a new prognostic model from a retrospective multicentric clinical study. Intergruppo Italiano Linfomi. Blood 2004;103:2474-9.[Abstract/Free Full Text]
4. Went P, Agostinelli C, Gallamini A, Piccaluga PP, Ascani S, Sabattini E, et al. Marker expression in peripheral T-cell lymphoma: a proposed clinical-pathologic prognostic score. J Clin Oncol 2006;24:2472-9.[Abstract/Free Full Text]
5. Gilleece MH, Dexter TM. Effect of Campath-1H antibody on human hematopoietic progenitors in vitro. Blood 1993;82:807-12.[Abstract/Free Full Text]
6. Rai KR, Freter CE, Mercier RJ, Cooper MR, Mitchell BS, Stadtmauer EA, et al. Alemtuzumab in previously treated chronic lymphocytic leukemia patients who also had received fludarabine. J Clin Oncol 2002;20:3891-7.[Abstract/Free Full Text]
7. Dearden C. The role of alemtuzumab in the management of T-cell malignancies. Semin Oncol 2006;33 Suppl_5: S44-52.[CrossRef][Web of Science][Medline]
8. Enblad G, Hagberg H, Erlanson M, Lundin J, MacDonald AP, Repp R, et al. A pilot study of alemtuzumab (anti-CD52 monoclonal antibody) therapy for patients with relapsed or chemotherapy-refractory peripheral T-cell lymphomas. Blood 2004;103:2920-4.[Abstract/Free Full Text]
9. Piccaluga PP, Agostinelli C, Califano A, Rossi M, Basso K, Zupo S, et al. Gene expression analysis of peripheral T-cell lymphoma/unspecified reveals distinct profiles and new potential therapeutic targets. J Clin Invest 2007;15[Epub ahead of print].
10. Salisbury JR, Rapson NT, Codd JD, Rogers MV, Nethersell AB. Immunohistochemical analysis of CDw52 antigen expression in non-Hodgkin’s lymphomas. J Clin Pathol 1994;47:313-7.[Abstract/Free Full Text]
11. Rodig SJ, Abramson JS, Pinkus GS, Treon SP, Dorfman DM, Dong HY, et al. Heterogeneous CD52 expression among hematologic neoplasms: implications for the use of alemtuzumab (CAMPATH-1H). Clin Cancer Res 2006;12:7174-9.[Abstract/Free Full Text]

This article has been cited by other articles:

				A. Gazzola, C. Bertuzzi, C. Agostinelli, S. Righi, S. A. Pileri, and P. P. Piccaluga Physiological PTEN expression in peripheral T-cell lymphoma not otherwise specified Haematologica, July 1, 2009; 94(7): 1036 - 1037. [Full Text] [PDF]

				C Agostinelli, P P Piccaluga, P Went, M Rossi, A Gazzola, S Righi, T Sista, C Campidelli, P L Zinzani, B Falini, et al. Peripheral T cell lymphoma, not otherwise specified: the stuff of genes, dreams and therapies J. Clin. Pathol., November 1, 2008; 61(11): 1160 - 1167. [Abstract] [Full Text] [PDF]

				S. M. Horwitz Novel Therapies and Role of Transplant in the Treatment of Peripheral T-Cell Lymphomas Hematology, January 1, 2008; 2008(1): 289 - 296. [Abstract] [Full Text] [PDF]

				A. Gallamini, F. Zaja, C. Patti, A. Billio, M. R. Specchia, A. Tucci, A. Levis, A. Manna, V. Secondo, L. Rigacci, et al. Alemtuzumab (Campath-1H) and CHOP chemotherapy as first-line treatment of peripheral T-cell lymphoma: results of a GITIL (Gruppo Italiano Terapie Innovative nei Linfomi) prospective multicenter trial Blood, October 1, 2007; 110(7): 2316 - 2323. [Abstract] [Full Text] [PDF]

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Piccaluga, P. P. Articles by Pileri, S. A. Search for Related Content PubMed PubMed Citation Articles by Piccaluga, P. P. Articles by Pileri, S. A.