CXCR4 expression enhances diffuse large B cell lymphoma dissemination and decreases patient survival.

The chemokine receptor CXCR4 has been implicated in the migration and trafficking of malignant B cells in several haematological malignancies. Over-expression of CXCR4 has been identified in haematological tumours, but data concerning the role of this receptor in diffuse large B cell lymphoma (DLBCL) are lacking. CXCR4 is a marker of poor prognosis in various neoplasms, correlating with metastatic disease and decreased survival of patients. We studied CXCR4 involvement in cell migration in vitro and dissemination in vivo. We also evaluated the prognostic significance of CXCR4 in 94 biopsies of DLBCL patients. We observed that the level of expression of CXCR4 in DLBCL cell lines correlated positively with in vitro migration. Expression of the receptor was also associated with increased engraftment and dissemination, and decreased survival time in NOD/SCID mice. Furthermore, administration of a specific CXCR4 antagonist, AMD3100, decreased dissemination of DLBCL cells in a xenograft mouse model. In addition, we found that CXCR4 expression is an independent prognostic factor for shorter overall survival and progression-free survival in DLBCL patients. These results show that CXCR4 mediates dissemination of DLBCL cells and define for the first time its value as an independent prognostic marker in DLBCL patients.

Focal adhesion protein expression in human diffuse large B-cell lymphoma.

AIMS: Focal adhesions have been associated with poor prognosis in multiple cancer types, but their prognostic value in diffuse large B-cell lymphoma (DLBCL) has not been evaluated. The aim of this study was to investigate the expression patterns and the prognostic value of the focal adhesion proteins FAK, Pyk2, p130Cas and HEF1 in DLBCL. METHODS AND RESULTS: Focal adhesion protein expression was examined using immunohistochemistry in normal lymphoid tissues and in 60 DLBCL patient samples. Kaplan-Meier survival and Cox regression analysis were performed to evaluate the correlation of focal adhesion protein expression with patient prognosis. FAK, Pyk2, p130Cas and HEF1 expression was mostly found in the germinal centres of normal human lymphoid tissues. When assessed in DLBCL samples, FAK, Pyk2, p130Cas and HEF1 were highly expressed in 45%, 34%, 42% and 45% of the samples, respectively. Multivariate Cox analysis revealed that decreased FAK expression was a significant independent predictor of poorer disease outcome. CONCLUSIONS: FAK expression is an independent prognostic factor in DLBCL. Our results suggest that the addition of FAK immunostaining to the current immunohistochemical algorithms may facilitate risk stratification of DLBCL patients.

A novel inhibitor of focal adhesion signaling induces caspase-independent cell death in diffuse large B-cell lymphoma.

Focal adhesion (FA) proteins have been associated with transformation, migration, metastasis, and poor outcome in many neoplasias. We previously showed that these proteins were inhibited by E7123, a new celecoxib derivative with antitumor activity, in acute myeloid leukemia. However, little is known about FAs in diffuse large B cell lymphoma (DLBCL). This paper aimed to determine whether E7123 was effective against DLBCL and whether FAs were involved in its action. We evaluated the cytotoxicity and mechanism of action of E7123 and celecoxib in DLBCL cell lines. We also assessed the E7123 in vivo activity in a DLBCL xenograft model and studied FA signaling in primary DLBCL patient samples. We found that E7123 showed higher antitumor effect than celecoxib against DLBCL cells. Its mechanism of action involved deregulation of FA, AKT, and Mcl-1 proteins, a pathway that is activated in some patient samples, apoptosis-inducing factor release and induction of caspase-independent cell death. Moreover, E7123 showed suppression of in vivo tumor growth. These findings indicate that E7123 is effective against DLBCL in vitro and in vivo, with a mechanism of action that differs from that of most current therapies for this malignancy. Our results support further preclinical evaluation of E7123.

A novel orally available inhibitor of focal adhesion signaling increases survival in a xenograft model of diffuse large B-cell lymphoma with central nervous system involvement.

Central nervous system dissemination is a relatively uncommon but almost always fatal complication in diffuse large B-cell lymphoma patients. Optimal therapy for central nervous involvement in this malignancy has not been established. In this paper, we aimed to evaluate the therapeutic effect of E7123, a celecoxib derivative that inhibits focal adhesion signaling, in a novel xenograft model of diffuse large B-cell lymphoma with central nervous system involvement. Cells obtained after disaggregation of HT subcutaneous tumors (HT-SC cells) were intravenously injected in NOD/SCID mice. These mice received oral vehicle or 75 mg/kg of E7123 daily until they were euthanized for weight loss or signs of sickness. The antitumor effect of E7123 was validated in an independent experiment using a bioluminescent mouse model. Intravenously injected HT-SC cells showed higher take rate and higher central nervous system tropism (associated with increased expression of ß1-integrin and p130Cas proteins) than HT cells. The oral administration of E7123 significantly increased survival time in 2 independent experiments using mice injected with unmodified or bioluminescent HT-SC cells. We have developed a new xenograft model of diffuse large B-cell lymphoma with central nervous system involvement that can be used in the pre-clinical evaluation of new drugs for this malignancy. E7123 is a new, well-tolerated and orally available therapeutic agent that merits further investigation since it may improve current management of diffuse large B-cell lymphoma patients with central nervous system involvement.

Cadherin-13, a mediator of calcium-dependent cell-cell adhesion, is silenced by methylation in chronic myeloid leukemia and correlates with pretreatment risk profile and cytogenetic response to interferon alfa.

PURPOSE: Cadherin-13 (CDH13) is a newly characterized cadherin molecule responsible for selective cell recognition and adhesion, the expression of which is decreased by methylation in a variety of human cancers, indicating that the CDH13 gene functions as a tumor suppressor gene. Although defective progenitor-stromal adhesion is a well-recognized feature of chronic myeloid leukemia (CML), the role of CDH13 abnormalities has not been evaluated in this disease. PATIENTS AND METHODS: We examined the methylation status of the CDH13 promoter in 179 chronic phase (CP)-CML patients and in 52 advanced-phase samples and correlated it with mRNA expression using methylation-specific polymerase chain reaction (PCR) and reverse transcriptase PCR. RESULTS: Aberrant de novo methylation of the CDH13 promoter region was observed in 99 (55%) of 179 of CP-CML patients, and 90 of the patients failed to express CDH13 mRNA (P <.0001). Advanced-stage samples (n = 52) showed concordant methylation results with their corresponding CP tumors, indicating that CDH13 methylation was not acquired during the course of the disease. Nevertheless, absence of CDH13 expression was more frequently observed among Sokal high-risk patients (P =.01) and was also independently associated with a shorter median progression-free survival time (P =.03) and poor cytogenetic response to interferon alfa treatment (P =.0001). CONCLUSION: Our data indicate that the silencing of CDH13 expression by aberrant promoter methylation occurs at an early stage in CML pathogenesis and probably influences the clinical behavior of the disease.

Treatment of primary acute myeloid leukemia: results of a prospective multicenter trial including high-dose cytarabine or stem cell transplantation as post-remission strategy.

BACKGROUND AND OBJECTIVES: To evaluate a regimen of induction and consolidation chemotherapy, followed by a post-remission therapy which depended on age and cytogenetics, in patients with primary acute myeloid leukemia. DESIGN AND METHODS: Two hundred patients up to 60 years old received idarubicin, standard dose cytarabine and etoposide as induction chemotherapy and one consolidation course including intermediate dose cytarabine and mitoxantrone. Subsequently, patients with favorable cytogenetics, [i.e., t(8;21), inv(16)] were scheduled to receive 2 courses of high-dose cytarabine. The remainder were scheduled for allogeneic stem cell transplantation (SCT), if 50 years old or lacking a donor. RESULTS: In patients with favorable cytogenetics the 4-year probabilities of survival and leukemia-free survival (LFS) were 62+/-9% and 41+/-10%, respectively. The results were better in patients with t(8;21). LFS at 4 years in patients 50 years old assigned to auto-SCT had a 4-year LFS of 17+/-9%. Adverse cytogenetics and white blood cell count >or= 20 yen 109/L at diagnosis were associated with lower probability of survival and leukemia-free survival. INTERPRETATION AND CONCLUSIONS: We confirmed that high-dose cytarabine seems a good option for patients with t(8;21). Autologous and allogeneic SCT led to similar leukemia-free survival in patients

Refractory cold agglutinin-immunohaemolytic anaemia associated to marginal zone lymphoma responding to rituximab.

Cold agglutinin immunohaemolytic anaemia (CAIA) responds poorly to standard treatment. We report a case of marginal zone lymphoma complicated by CAIA that responded to rituximab after failing to respond to corticosteroids and chlorambucil.

Novel dic(16;18)(q11;p11) in two cases of Philadelphia chromosome positive acute B-cell lymphoblastic leukemia.

We report two adult patients with Philadelphia chromosome positive (Ph+) B-cell acute lymphoblastic leukemia (ALL) who presented an additional dic(16;18)(q11;p11) that, to the best of our knowledge, has never been previously reported. Fluorescence in situ hybridization analysis confirmed the translocation and showed it to be dicentric. Both patients were treated for the ALL, but showed refractory disease and died despite aggressive treatment. Similarly to what has been reported with other additional chromosome abnormalities, our cases suggest that the presence of this novel translocation confers an adverse effect to the already poor prognosis of Ph+ ALL.

A relapsed non-Hodgkin lymphoma presenting as panhypopituitarism successfully treated by chemotherapy.

We report a case of relapsed large B-cell non-Hodgkin lymphoma (NHL) affecting the anterior pituitary. The NHL relapsed after three years in complete remission. The patient was a 72-year-old woman who presented fever, weakness, hyponatremia, and hypotension. The levels of thyroid-stimulating hormone and gonadotropins were very low and magnetic resonance imaging showed infiltration of the pituitary gland and stalk. After controlling the hormonal deficiencies with substitution using hydroxycortisone and levothyroxin, the patient was treated with combination chemotherapy using cyclophosphamide, vincristine, mitoxantrone, etoposide, and bleomycin (VNCOP-B regimen), achieving a complete regression of the pituitary mass and partial recovery of the endocrine function. Lymphoproliferative disorders affecting the anterior pituitary are exceedingly rare, with only six cases in immunocompetent adults reported in the literature. To our knowledge this is the first report of a relapsed NHL presenting by hypopituitarism.

Outcome and toxicity of salvage treatment on patients relapsing after autologous hematopoietic stem cell transplantation--experience from a single center.

Patients with hematological malignancies who relapse after autologous stem cell transplantation (auto-SCT) generally have poor prognosis. Salvage treatment is often associated with severe toxicities. The aim of our study was to evaluate retrospectively the toxicity and outcome of rescue therapy in patients with acute leukemias, non-Hodgkin's lymphoma (NHL), Hodgkin's disease (HD) and multiple myeloma (MM) relapsing after auto-SCT. Fifty-four of the 62 patients who relapsed received some form of salvage chemotherapy. Six (10%) patients were treated by second stem cell transplantation, which was allogeneic in 5 cases. Toxicity of the salvage therapy was significant. As a result of adverse effects, salvage therapy had to be discontinued or reduced in 14 patients (26%). The outcome of salvage was evaluated after 90 days. Of the treated patients, 14 (26%) entered into complete remission with another 5 (9%) reaching partial response. The disease was stabilized in 5 patients (9%) but 30 (56%) patients were in progression or dead. Overall survival of the patients was poor with the median survival of 8.7 months after relapse and the leading cause of death being progressive disease. In conclusion, the development of new, more efficient regimens is critical if disease-free survival is to be increased in patients who relapse after auto SCT.

Mixed chimerism is frequent after allogeneic peripheral blood stem cell transplantation with positive CD34 selection, and is not reverted by low doses of donor T-cells add-back.

UNLABELLED: The incidence of full donor chimerism (full DC) after CD34+ -selected peripheral blood stem cell transplantation (CD34+ -PBSCT) is controversial. Whereas the initial reports suggested a high incidence of full DC (hypothetically because of the high number of CD34+ cells infused) more recent works describe a high incidence of mixed lymphoid chimerism. There are no data concerning the ability of low-dose donor T-lymphocyte add-back on conversion to full DC. METHODS: We prospectively monitored the chimerism status of 25 patients undergoing CD34+ -PBSCT and the effect on chimerism of delayed low doses of donor T-cell add-back (TCAB). One, two or three doses of TCAB were administered on days +28 (2 x 10(5) CD3+/kg), +60 (2 x 10(5) CD3+/kg) and +90 (2 x 10(6) CD3+/kg), respectively, when on cyclosporine A prophylaxis. RESULTS: Incidence of full DC on day +20 was 56%. However, all but two patients progressed to MC. Fifteen patients were scheduled to TCAB. Six patients with initial MC did not convert to full DC after TCAB. Moreover, seven patients with full DC status progressed to mixed chimerism. CONCLUSIONS: Our results indicate that low doses of TCAB administered under cyclosporine A prophylaxis have no effect on the eradication of the recipient cells. We believe that a high dose of CD34+ cells in the grafts of CD34+ -PBSCT is not enough to achieve stable full DC unless a minimum number of CD3+ cells are infused, or more intensified transplant conditioning regimens are employed.

CD38 expression in B-chronic lymphocytic leukemia: association with clinical presentation and outcome in 155 patients.

BACKGROUND AND OBJECTIVES: To investigate whether CD38 expression at diagnosis is an independent predictor of survival and assess its associations with other clinical parameters used in the staging of B-cell chronic lymphocytic leukemia (B-CLL). DESIGN AND METHODS: CD38 expression was analyzed in 155 consecutive unselected patients newly diagnosed with B-CLL from January 1991 to July 1997. In all cases CD38 expression was evaluated at diagnosis and patients were classified into two groups: those with > or = 30% were considered positive (CD38+) and those with < 30% were considered negative (CD38-). Statistical differences between each group were analyzed using c2 tests for categorical variables and Student's t-tests for continuous variables. Survival analysis was performed at the univariate level by the Kaplan Meier technique and at the multivariate level by Cox hazard models. RESULTS: Thirty (19%) patients were CD38+. CD38+ was associated with atypical morphology (p=0.004), a diffuse bone marrow pattern (p=0.016), Rai stage > or =2 (p=0.009), high lactate dehydrogenase (p=0.02), high b2 microglobulin (p=0.004), and higher lymphocyte count (p=0.02). Furthermore, CD38+ patients required treatment more frequently (p=0.006) and CLL-related mortality was significantly higher (p=0.012). When we divided the study group into patients with Rai 0-1 and Rai 2-4 stages, CD38 positivity was only significantly associated with mortality in the early stage patients (p= 0.012 vs p= 0.68). CD38 expression in the multivariate analysis lost its statistical significance. None of these results was modified when the CD38 cut-off was set at 20%. INTERPRETATION AND CONCLUSIONS: CD38 expression identifies a subgroup of B-CLL patients with aggressive clinical presentation and worse outcome. Its expression is probably associated with other prognostic factors, but the feasibility of determining this parameter makes it easily reproducible and adds prognostic information at diagnosis to aid prediction of the clinical course and outcome of B-CLL.