Carolina Oliver

S100-A9 protein in exosomes from chronic lymphocytic leukemia cells promotes NF-κB activity during disease progression

Chronic lymphocytic leukemia (CLL) is an incurable disease characterized by accumulation of clonal B lymphocytes, resulting from a complex balance between cell proliferation and apoptotic death. Continuous crosstalk between cancer cells and local/distant host environment is required for effective tumor growth. Among the main actors of this dynamic interplay between tumoral cells and their microenvironment are the nano-sized vesicles called exosomes. Emerging evidence indicates that secretion, composition, and functional capacity of exosomes are altered as tumors progress to an aggressive phenotype. In CLL, no data exist exploring the specific changes in the proteomic profile of plasma-derived exosomes from patients during disease evolution. We hereby report for the first time different proteomic profiles of plasma exosomes, both between indolent and progressive CLLs as well as within the individual patients at the onset of disease and during its progression. Next, we focus on the changes of the exosome protein cargoes, which are found exclusively in patients with progressive CLL after disease progression. The alterations in the proteomic cargoes underline different networks specific for leukemia progression related to inflammation, oxidative stress, and NF-κB and phosphatidylinositol 3-kinase/AKT pathway activation. Finally, our results suggest a preponderant role for the protein S100-A9 as an activator of the NFκB pathway during CLL progression and suggest that the leukemic clone can generate an autoactivation loop through S100-A9 expression, NF-κB activation, and exosome secretion. Collectively, our data propose a new pathway for NF-κB activation in CLL and highlight the importance of exosomes as extracellular mediators promoting tumor progression in CLL.

Comparación entre CHOP-like y R-CHOP en pacientes con linfoma no Hodgkin difuso de grandes células B y folicular: 10 años de experiencia del Hospital de Clínicas de Montevideo, Uruguay

BACKGROUND The most common types of non-Hodgkin lymphoma (NHL) are diffuse large B cell (DLBCL) and follicular (FL). AIM To analyze the benefit of Rituxi-mab in overall survival (OS) of patients with NHL. MATERIAL AND METHODS Review of medical record of 230 adult patients with a first episode of NHL admitted between 2002 and 2011. We included 67 patients with DLBCL and 36 patients with FL. RESULTS The overall response (OR) was 64% with 39% complete remissions (CR) in DLBCL treated with CHOP-like and 100% with 89% CR with R-CHOP. The median OS with CHOP-like was 21 months versus not attained R-CHOP (p = 0.016). There was a statistically significant difference in median event-free survival (EvFS) in favor of R-CHOP: not attained versus 8.3 months for CHOP-like (log rank (p = 0.002)). In FL, the OR in patients treated with R-CHOP or R-CHOP-like was 85%) with 54% CR. With CHOP-like the OR was 59%> with 18% CR. The OS at 24 and 36 months in patients treated with R-CHOP or R-CHOP-like was 83 and 65%. The figures for patients treated with CHOP-like were 80 and 66%> respectively. The progression free survival (PFS) was 21 months with CHOP-like versus not attained with R-QT (p = 0,043). CONCLUSIONS When Rituximab was added to CHOP, there was a higher CR, EvFS and OS in DLBCL and higher CR and PFS in FL.

LPL protein in Chronic Lymphocytic Leukaemia have different origins in Mutated and Unmutated patients. Advances for a new prognostic marker in CLL

Lipoprotein lipase (LPL) mRNA expression in chronic lymphocytic leukaemia (CLL) is associated with an unmutated immunoglobulin profile and poor clinical outcome. We evaluated the subcellular localization of LPL protein in CLL cells that did or did not express LPL mRNA. Our results show that LPL protein is differently located in CLL cells depending on whether it is incorporated from the extracellular medium in mutated CLL or generated de novo by leukaemic cells of unmutated patients. The specific quantification of endogenous LPL protein correlates with mRNA expression levels and mutational IGHV status, suggesting LPL protein as a possible reliable prognostic marker in CLL.

Current imaging follow-up of non-Hodgkin lymphoma exposes patients to significant radiation but does not detect asymptomatic relapses.

Abstract The standard approach to the follow-up of lymphoma includes computed tomography (CT) every 6–12 months for the first 2 years and, then, as clinically indicated. Recent evidence suggests that most relapses are detected clinically, outside scheduled CT which, on the other hand, increases risk of second malignancies and cost. In early-stage lymphomas, involved site CT instead of full body CT may be a reasonable alternative to reduce radiation dose. We analyzed whether regular CT surveillance detects asymptomatic relapses in a single-center Uruguayan early stage non-Hodgkin lymphoma (NHL) population. We evaluated utility of full body CT halfway and at the end-of-treatment evaluation and calculated the radiation exposure. In our study, CT surveillance added nothing to clinical follow-up. Moreover, 44% of our patients received a cumulative effective dose that doubles the risk of malignancies. Involved-site CT scan would be enough to monitor response during treatment in early stage NHL.