Diffuse large B-cell lymphomas (DLBCLs) represent 25 to 30% of adult non-Hodgkin lymphomas in western countries. DLBCLs are aggressive cancer but potentially curable with multi-agent chemotherapy. Whereas R-CHOP regimen has led to a marked improvement in survival, this disease remains a biologically heterogeneous entity. New therapeutic strategies are required including identification of patients' subgroups with different prognostic.

This project is based on BMS_LyTrans and Goelams 075 clinical trial. A study of whole blood transcriptome in 75 DLBCL patients and in 87 controls showed that PD-L1 (CD274) gene was overexpressed in DLBCL patients. Preliminary results demonstrated that PD-L1 is detected in plasma of DLBCL patients with a significantly higher concentration than in controls. This protein was selected as a potential biomarker because of its established role in anti-tumoral immunity. Interaction between PD-L1 and its receptor PD-1 is known to inhibit activation of immune responses by inducing T-lymphocytes anergy and/or apoptosis. Moreover, a direct involvement of PD-L1 in the protection of cancer cells from lysis by activated T lymphocytes has been demonstrated. PD-L1 expression has been described in several solid tumours, including ovary cancer, breast cancer, colon cancer, renal cell carcinoma, non-small cell lung carcinoma and in hematological malignancies such as T-NHL, MM and Hodgkin's lymphoma. Furthermore the expression of PD-L1 by tumour cells is associated with poor prognosis. The blockade of PD-L1/PD-1 axis may represent a novel therapeutic approach in aggressive cancers. These first results incite to identify the cells releasing soluble PD-L1 and to investigate its role in the anti-tumoral immunity in DLBCL patients.

The aim of this study is to identify cells producing soluble PD-L1 in DLBCL patients at diagnosis in comparison to others tumours known to express PD-L1 (metastatic breast cancer, Hodgkin's lymphoma, non-small cell lung cancer).

Secondary purposes are :

• To confirm the presence of plasma soluble form of PD-L1 in others malignancies
• To study surface expression of PD-L1 on circulating tumour cells with multiparameter fow cytometry and Veridex® technology in DLBCL and metastatic breast cancer patients
• To study surface expression of PD-L1 on circulating endothelial cells in DLBCL, Hodgkin lymphoma and metastatic breast cancer patients (subpart ended in late 2012)
• To study surface expression of PD-L1 on different types of leukocytes (monocytes, B and T lymphocytes)
• To separate circulating tumour cells expressing PD-L1 by immunomagnetic or Cell-sorting method
• To develop ELISPOT technique to study the release of soluble PD-L1 in culture supernatants of selected cells (subpart ended mid 2013)
• to evaluate the correlation between the expression of PD-L1 in the plasma and *) the expression of PD-L1 in the tumor, **) the expression of PD-L1 and other molecules in the bronchoalveolar liquid (whenever available from routine) in non-small cell lung cancer
• to evaluate the response to treatment according to plasma PD-L1 expression in non-small cell lung cancer
• to evaluate the susceptibility to develop a disease according to the single nucleotide polymorphisms of the PD-L1 gene in DLBCL and non-small cell lung cancer
• Constitution of the different cohorts and collection of samples Main cohort : de novo DLBCL at diagnosis Secondary cohorts: Hodgkin's lymphoma, metastatic breast cancer, non small cell lung cancer Control cohorts : healthy volunteers (blood donors), patients with immune thrombocytopenia (ITP)
• Quantification of plasma soluble PD-L1 in the different cohorts

Inclusion Criteria:

General inclusion criteria :

• Age ≥ 18 years and ≤ 75 years,
• Life expectancy more than 4 months
• Signed informed consent obtained
• Social security affiliation is mandatory
• Non previously treated (even by corticotherapy),
• HIV negative, HBs negative, HCV negative

Inclusion criteria for DLBCL patients :

• A biopsy proven diagnosis of de novo DLBCL according to the current WHO criteria,
• Immunohistochemistry for GCB/nonGC classification according to Hans' algorithm
• Patients with advanced-stage disease defined as Ann Arbor stages III or IV, or stages I or II with bulky disease (>7cm)

Inclusion criteria for non-small cell lung cancer patients :

• A biopsy proven diagnosis of de novo non-small cell lung cancer (all stages) according to the current WHO criteria

Inclusion criteria for Hodgkin's lymphoma patients :

• A biopsy proven diagnosis of Hodgkin's lymphoma according to the current WHO criteria

Inclusion criteria for metastatic breast cancer or with lymph node involvement :

• A biopsy proven diagnosis infiltrating lobular or ductal breast carcinoma
• with lymph node involvement or metastasis

Inclusion criteria for patients with immune thrombocytopenia (ITP) :

• Primary ITP was defined by the IWG as a platelet count less than 100 G/L in the absence of other causes or disorders that may be associated with thrombocytopenia.
• Bone marrow examination excluding a central aetiology of thrombocytopenia

Inclusion criteria for healthy volunteers :

- Inclusion criteria for blood donation according to the Etablissement Français du Sang (EFS) criteria

Exclusion Criteria:

General non-inclusion criteria :

• Age < 18 years et > 75 years,
• Pregnant women,
• Person legally involved in a case
• No social security affiliation
• Signed informed consent not obtained,
• Preliminary treatment (even corticoid treatment).
• HIV positive, HBs positive, HCV positive

Non-inclusion criteria for DLBCL patients :

• Lymphoma other than DLBCL,
• Transformation of a low grade lymphoma to a high grade lymphoma (DLBCL),
• Extranodal marginal zone lymphoma of MALT lymphoma,
• Post-transplant lymphoproliferative disorders,
• Lymphoblastic lymphoma,
• Burkitt's lymphoma,
• Carcinoma or history of carcinoma except in situ cervical carcinoma.

Non-inclusion criteria for non-small cell lung cancer patients : None

Non-inclusion criteria for Hodgkin patients :

- Non Hodgkin's lymphoma

Non-inclusion criteria for metastatic breast cancer or with lymph node involvement :

• Carcinoma other than infiltrating lobular or ductal breast carcinoma
• Chemotherapy in 30 days preceding the inclusion
• Hormonotherapy in 7 days preceding the inclusion
• Carcinoma or history of carcinoma except in situ cervical carcinoma.
• Hemoglobin level < 10g/dl

Non-inclusion criteria for patients with immune thrombocytopenia (ITP) :

- Central aetiology of the thrombocytopenia

Non-inclusion criteria for healthy volunteers :

- Exclusion criteria for blood donation according to the Etablissement Français du Sang (EFS) criteria

Number of DLBCL patients : 40 Number of non-small cell lung cancer patients : 100 Number of Hodgkin patients : 20 Number of metastatic breast cancer patients : 20 Number of healthy volunteers : 140 Number of patients with immune thrombocytopenia (ITP) : 5