Extracorporeal Photopheresis: Scientific and Technical Considerations for Improving Clinical Management of Patients

International audienceExtracorporeal photopheresis or chemophototherapy (ECP) is a current therapy and concept that has demonstrated clinical efficacy in the treatment of acute and chronic graft versus host disease (GVHD), Sezary syndrome or cutaneous T-cell lymphoma (CTCL) and organ transplant rejection. Patient inclusion in ECP protocols increases due to the diffusion of technical progress but has to be explored regarding various schedules and processes. ECP mechanisms of action are still unclear despite evident implication of a complex cascade beginning from the apoptosis of the various cell types collected and exposed to the process that is followed by an immunomodulation via antigen presentation. Exploration of the mechanisms in animal models has many limits that weakness human clinical link. Beside major indications, the barrier to ECP treatment extension is the absence of randomized trials in comparison to alternative therapies. The cost of ECP treatment is also a limitation and has to be evaluated relative to other strategies. Nevertheless, the efficacy and the absence of major side effects deserve attention, mainly for the extension of the ECP treatment in clinical trials as new therapeutic line

Front-line high-dose chemotherapy with rituximab showed excellent long-term survival in adults with aggressive large b-cell lymphoma: final results of a Phase II GOELAMS Study.

International audienceTo evaluate the effect of rituximab in poor-prognosis patients with diffuse large B-cell lymphoma (DLBCL), a multicenter phase II trial combining rituximab with chemotherapy followed by high-dose therapy (HDT) with autologous stem cell transplant was conducted by the Groupe Ouest-Est des Leucémies et des Autres Maladies du Sang (GOELAMS). Patients were aged 18 to 60 years, with newly diagnosed CD20-expressing DLBCL, and at least 2 adverse risk factors as defined by the age-adjusted International Prognostic Index (aa-IPI). The treatment consisted of 2 courses of high-dose CHOP-like regimen on day 1 and 15 and 1 course of methotrexate and cytarabine on day 36. Four doses of rituximab (375 mg/m(2)) were infused on days 1, 15, 22, and 36. For patients who achieved at least a partial remission (PR), HDT followed by autologous stem cell transplant was performed on day 66. From April 2002 to May 2003, 42 patients were eligible. Half were high aa-IPI risk patients. Thirty-eight patients (90%) completed the treatment. Treatment-related mortality was 7% and no toxic death was related to rituximab. Complete response rate after the end of the full treatment was 67%. With a median follow-up of 66 months, event-free survival and overall survival rates were 55% and 74%, respectively. Median survival was not reached. First-line HDT with rituximab offers promising results for young adults with intermediate high or high aa-IPI high-grade lymphoma. Immediate and late toxicities were low. This treatment is being randomly compared prospectively with CHOP-14-rituximab in young adults with DLBCL (GOELAMS 075 trial)

Targeting early B-cell receptor signaling induces apoptosis in leukemic mantle cell lymphoma.

International audienceBACKGROUND: We previously showed that B-cell receptor (BCR) signaling pathways are important for in vitro survival of mantle cell lymphoma (MCL) cells. To further identify early BCR-activated signaling pathways involved in MCL cell survival, we focused our study on BCR-proximal kinases such as LYN whose dysregulations could contribute to the aggressive course of MCL. METHODS: Primary MCL cells were isolated from 14 leukemic patients. Early BCR-induced genes were identified by qRT-PCR array. The basal and BCR-induced phosphorylation of LYN and JNK were evaluated by immunoblottting. Cell survival signals were evaluated by apoptosis using flow cytometry. RESULTS: We showed that LYN was constitutively phosphorylated in MCL cell lines and in 9/10 leukemic MCL cases. Treatment with dasatinib or with a specific inhibitor of Src kinases such as PP2 suppressed constitutive LYN activation and increased in vitro spontaneous apoptosis of primary MCL cells. BCR engagement resulted in an increase of LYN phosphorylation leading to activation of c-JUN NH2-terminal kinase (JNK) and over-expression of the early growth response gene-1 (EGR-1). Inhibition of JNK with SP600125 induced apoptosis and reduced level of basal and BCR-induced expression of EGR-1. Furthermore, decreasing EGR1 expression by siRNA reduced BCR-induced cell survival. Treatment with PP2 or with dasatinib suppressed BCR-induced LYN and JNK phosphorylation as well as EGR-1 upregulation and is associated with a decrease of cell survival in all cases analysed. CONCLUSIONS: This study highlights the importance of BCR signaling in MCL cell survival and points out to the efficiency of kinase inhibitors in suppressing proximal BCR signaling events and in inducing apoptosis

Targeting early B-cell receptor signaling induces apoptosis in leukemic mantle cell lymphoma

Abstract Background We previously showed that B-cell receptor (BCR) signaling pathways are important for in vitro survival of mantle cell lymphoma (MCL) cells. To further identify early BCR-activated signaling pathways involved in MCL cell survival, we focused our study on BCR-proximal kinases such as LYN whose dysregulations could contribute to the aggressive course of MCL. Methods Primary MCL cells were isolated from 14 leukemic patients. Early BCR-induced genes were identified by qRT-PCR array. The basal and BCR-induced phosphorylation of LYN and JNK were evaluated by immunoblottting. Cell survival signals were evaluated by apoptosis using flow cytometry. Results We showed that LYN was constitutively phosphorylated in MCL cell lines and in 9/10 leukemic MCL cases. Treatment with dasatinib or with a specific inhibitor of Src kinases such as PP2 suppressed constitutive LYN activation and increased in vitro spontaneous apoptosis of primary MCL cells. BCR engagement resulted in an increase of LYN phosphorylation leading to activation of c-JUN NH2-terminal kinase (JNK) and over-expression of the early growth response gene-1 (EGR-1). Inhibition of JNK with SP600125 induced apoptosis and reduced level of basal and BCR-induced expression of EGR-1. Furthermore, decreasing EGR1 expression by siRNA reduced BCR-induced cell survival. Treatment with PP2 or with dasatinib suppressed BCR-induced LYN and JNK phosphorylation as well as EGR-1 upregulation and is associated with a decrease of cell survival in all cases analysed. Conclusions This study highlights the importance of BCR signaling in MCL cell survival and points out to the efficiency of kinase inhibitors in suppressing proximal BCR signaling events and in inducing apoptosis

Identification, characterisation and regulation by CD40 activation of novel CD95 splice variants in CD95-apoptosis-resistant, human, B-cell non-Hodgkin's lymphoma.

International audienceCD95 gene and splicing aberrations have been detected in B-cell non-Hodgkin lymphoma (B-NHL) where they are thought to contribute to CD95 apoptosis resistance. To further investigate this, we have performed extensive CD95 transcript sequencing and functional analysis in B-NHL with demonstrated resistance to CD95-induced apoptosis (B-NHLr). Strikingly, instead of showing CD95 mutations per se, B cells from B-NHLr co-expressed wild-type and multiple, normal (CD95nv) and novel alternatively spliced variant CD95 transcripts (CD95av). CD95av were predicted, by sequencing, to encode soluble, potentially apoptosis inhibitory proteins. However, their overexpression, by transfection, in Jurkat cells did not interfere with endogenous CD95 death signalling. Furthermore, CD95av-expressing B-NHLr did not show mutations in CD95 splice-regulatory elements and CD95av expression was 'reversible' by CD40 activation. This, in conjunction with treatment by the protein synthesis inhibitor, cycloheximide, could sensitise a subset of B-NHLr to CD95 apoptosis. In normal and lymphoma B cells, this correlated to increased CD95 membrane expression, enhanced DISC activity and engagement of the mitochondrial death pathway via Bid cleavage, although the latter occurred less efficiently in B-NHLr. Thus, immune modulation of CD95 transcription and alternative splicing combined with enhanced engagement of mitochondrial death signalling offer potential for restoration of CD95 apoptosis sensitivity in B-NHLr

Hypogammaglobulinemia during Rituximab Maintenance after Transplantation Is a Surrogate Marker for Disease Control in Patients with Mantle-Cell Lymphoma, an Analysis from the LyMa Trial

International audienceHypogammaglobulinemia during Rituximab Maintenance after Transplantation Is a Surrogate Marker for Disease Control in Patients with Mantle-Cell Lymphoma, an Analysis from the LyMa Tria