High-dose chemotherapy supported by autologous stem cell transplantation (HDT/ASCT) has contributed to modify the natural history of follicular lymphoma (FL); however, an overall survival (OS) benefit has been demonstrated at relapse only after a rituximab-free chemotherapy regimen. A total of 655 patients with FL were reported to the Spanish GELTAMO (Grupo Español de Linfomas y Trasplantes de Médula Ósea) registry and underwent first ASCT between 1989 and 2007. A total of 203 patients underwent ASCT in first complete response (CR1), 174 in second complete response (CR2), 28 in third complete response (CR3), 140 in first partial response (PR1), 81 in subsequent PR, and 29 with resistant/refractory disease; 184 patients received rituximab before ASCT. With a median follow-up of 12 years from ASCT, median progression-free survival (PFS) and overall survival (OS) were 9.7 and 21.3 years, respectively. Actuarial 12-year PFS and OS were 63% (95% confidence interval [CI], 58%-68%) and 73% (95% CI, 68%-78%), respectively, for patients in CR (with a plateau in the curve beyond 15.9 years), 25% (95% CI, 19%-28%) and 49% (95% CI 42%-56%), respectively, for patients in PR, and 23% (95% CI, 8%-48%) and 28% (95% CI, 9%-45%), respectively, for patients with resistant/refractory disease (P < .001). In patients who received rituximab before ASCT, the estimated 9-year PFS and OS from ASCT were 59.5% (95% CI, 51%-67%) and 75% (95% CI, 68%-83%), respectively. Interestingly, for patients who underwent transplantation in CR ≥2 or PR ≥2 who had received rituximab before ASCT (n = 90), 9-year PFS and OS were 61% (95% CI, 51%-73%) and 75% (95% CI, 65%-80%), respectively, with no relapses occurring beyond 5.1 years after ASCT. The cumulative incidence of second malignancies in the global series was 6.7% at 5 years and 12.8% at 10 years. This analysis strongly suggests that ASCT is a potentially curative option for eligible patients with FL. In the setting of relapse, it is of especial interest in pretransplantation rituximab-sensitive patients with FL.

JAK-STAT signaling through the JAK2V617F mutation is central to the pathogenesis of myeloproliferative neoplasms (MPN). However, other events could precede the JAK2 mutation. The aim of this study is to analyze the phenotypic divergence between polycytemia vera (PV) and essential thrombocytemia (ET) to find novel therapeutics targets by a proteomic and functional approach to identify alternative routes to JAK2 activation. Through 2D-DIGE and mass spectrometry of granulocyte protein from 20 MPN samples, showed differential expression of HSP70 in PV and ET besides other 60 proteins. Immunohistochemistry of 46 MPN bone marrow samples confirmed HSP70 expression. The median of positive granulocytes was 80% in PV (SD 35%) vs. 23% in ET (SD 34.25%). In an ex vivo model KNK437 was used as an inhibition model assay of HSP70, showed dose-dependent inhibition of cell growth and burst formation unit erythroid (BFU-E) in PV and ET, increased apoptosis in the erythroid lineage, and decreased pJAK2 signaling, as well as a specific siRNA for HSP70. These data suggest a key role for HSP70 in proliferation and survival of the erythroid lineage in PV, and may represent a potential therapeutic target in MPN, especially in PV.

Purpose: The microbiota is recognized as an important contributor to the efficacy of immunotherapies. The aim of this study is to analyze the role of gut microbiota and related metabolites in the response of chimeric antigen receptor (CAR) T cells for non-Hodgkin lymphoma. Experimental Design: Stool, serum, and clinical data were collected from 84 patients with non-Hodgkin lymphoma from four hospitals before CD19 CAR T-cell treatment. The microbiota was characterized through 16S rRNA gene sequencing, and serum short-chain fatty acids (SCFA) were measured using mass spectrometry. CAR T cells were exposed to butyrate; their in vitro cytotoxicity was determined, and molecular mechanisms were characterized by flow cytometry and RNA sequencing and then assessed in an in vivo model. Results: As we confirmed the negative impact of antibiotics on the response, we delved into the mechanisms involved. We showed that they reduce microbiota diversity and that their composition correlates with the response. We identified SCFA-producing bacterial groups, including Prevotella, Ruminococcus, and Butyricicoccus, as having a relatively higher abundance in the microbiota of patients who responded to CAR T cells. Analysis of butyrate levels revealed a positive correlation with survival, potentially representing a novel biomarker of response. Finally, we found that stimulation of CAR T cells with butyrate induced phenotypic and transcriptomic changes associated with enhanced antitumor efficacy. Conclusions: Our results support the relationship between microbiota and CAR T-cell therapy major outcomes. Analysis of microbiota led to the identification of SCFAs, especially butyrate, as a prognostic factor, and also provides the basis for considering them as chemical modifiers of CAR T cells to improve their efficacy.