RESUMEN
The protease MALT1 promotes lymphocyte activation and lymphomagenesis by cleaving a limited set of cellular substrates, most of which control gene expression. Here, we identified the integrin-binding scaffold protein Tensin-3 as a MALT1 substrate in activated human B cells. Activated B cells lacking Tensin-3 showed decreased integrin-dependent adhesion but exhibited comparable NF-κB1 and Jun N-terminal kinase transcriptional responses. Cells expressing a noncleavable form of Tensin-3, on the other hand, showed increased adhesion. To test the role of Tensin-3 cleavage in vivo, mice expressing a noncleavable version of Tensin-3 were generated, which showed a partial reduction in the T cell-dependent B cell response. Interestingly, human diffuse large B cell lymphomas and mantle cell lymphomas with constitutive MALT1 activity showed strong constitutive Tensin-3 cleavage and a decrease in uncleaved Tensin-3 levels. Moreover, silencing of Tensin-3 expression in MALT1-driven lymphoma promoted dissemination of xenografted lymphoma cells to the bone marrow and spleen. Thus, MALT1-dependent Tensin-3 cleavage reveals a unique aspect of the function of MALT1, which negatively regulates integrin-dependent B cell adhesion and facilitates metastatic spread of B cell lymphomas.
Asunto(s)
Caspasas , Linfoma de Células B Grandes Difuso , Ratones , Humanos , Animales , Adulto , Tensinas/genética , Caspasas/metabolismo , FN-kappa B/metabolismo , Adhesión Celular/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteína 1 de la Translocación del Linfoma del Tejido Linfático Asociado a Mucosas/genética , Proteína 1 de la Translocación del Linfoma del Tejido Linfático Asociado a Mucosas/metabolismo , Linfoma de Células B Grandes Difuso/genética , IntegrinasRESUMEN
Health-related quality of life (HRQoL) data are important indicators of health status in patients with lymphoma. The objective of this analysis was to assess the impact of treatment with Sandoz rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) on HRQoL in treatment-naïve adult patients with diffuse large B-cell lymphoma (DLBCL) included in the prospective, real-world REFLECT study. REFLECT is the first prospective study to assess HRQoL in patients with DLBCL treated with a rituximab biosimilar. HRQoL was assessed via the patient-reported European Organization for Research and Treatment of Cancer Core Quality of Life questionnaire at baseline, mid-treatment (month 3), end of treatment (month 6), and follow-up (months 9 and 12). Subgroup analyses were performed to evaluate the influence of baseline characteristics on HRQoL, and associations between baseline HRQoL and treatment response. HRQoL was assessed in 169 patients. Mean global health status score remained stable from baseline (54.8) to mid-treatment (month 3; 54.7), before steadily improving through to end of treatment (month 6; 61.4), and follow-up month 9 (64.9) and month 12 (68.8). Similar trends were observed across most functional and symptom subscales. Higher cognitive, physical, or role functioning, and less appetite loss, diarrhea, fatigue, or pain at baseline, were all associated with an improved likelihood of reaching a complete versus partial response at the end of treatment. Overall, these findings confirm the HRQoL benefits of R-CHOP therapy in treatment-naïve adult patients with DLBCL, and suggest that baseline HRQoL may be predictive of treatment response.