Amine Belhabri

Major Molecular Response Achievement in CML Patients Can Be Predicted by BCR-ABL1/ABL1 or BCR-ABL1/GUS Ratio at an Earlier Time Point of Follow-Up than Currently Recommended

Recent studies demonstrate that early molecular response to tyrosine-kinase inhibitors is strongly predictive of outcome in chronic myeloid leukemia patients and that early response landmarks may identify patients at higher risk for transformation who would benefit from an early switch to second-line therapy. In this study, we evaluated the ability of the control gene GUS to identify relevant thresholds for known therapeutic decision levels (BCR-ABL1/ABL1IS  = 10% and 0.1%). We then defined the most relevant cut-offs for early molecular response markers (transcript level at 3 months, halving time and log reduction between diagnosis and 3 months of treatment) using GUS or ABL1. We demonstrated that, although both control genes could be used (in an equivalent way) to accurately assess early molecular response, the BCR-ABL1/GUS level at diagnosis is impacted by the higher GUS copy number over-expressed in CML cells, thus negatively impacting its ability to completely replace ABL1 at diagnosis. Furthermore, we pointed out, for the first time, that it would be helpful to monitor BCR-ABL1 levels at an earlier time point than that currently performed, in order to assess response to first-line tyrosine-kinase inhibitors and consider a potential switch of therapy as early as possible. We evaluated this optimal time point as being 19 days after the start of treatment in our cohort.

Impact of the introduction of rituximab in first‐line follicular lymphoma: a retrospective study of 247 unselected patients referred to a single institution with a long‐term follow‐up

Rituximab was approved in France in 2004, following randomized trials that demonstrated efficacy in newly diagnosed high tumour burden follicular lymphoma (FL). This retrospective study compared the management and outcome of FL in unselected patients treated in a single institution before and after rituximab approval. Two hundred and forty‐seven adult patients were referred with first‐line FL between 1996 and 2010 and are included in this study. The 103 pre‐rituximab patients comprising cohort 1 were diagnosed between January 1996 and December 2003; cohort 2 includes the 144 patients diagnosed after the approval of rituximab between January 2004 and December 2010. Baseline clinical and biological data, type of therapy, treatment response, progression‐free survival (PFS) and overall survival (OS) rates were compared. There were no statistically significant differences between the two cohorts with respect to baseline clinical and disease characteristics, including FL International Prognostic Index score. The major difference between the two cohorts is the use of rituximab in first line. Seventy‐one per cent of patients in cohort 2 received rituximab (19% alone, 52% with chemotherapy) versus 10% in cohort 1 (2% alone, 8% with chemotherapy; p < 0.0001). The objective response rate (ORR) was significantly higher for cohort 2 (ORR 84% compared with 72% for cohort 1; p = 0.03). The PFS and OS rates were also significantly better: 3‐year PFS 72% [95% confidence interval (CI) 64–80%] versus 55% (95% CI 45–64%), p = 0.0039 and 3‐year OS 98% (95% CI 94–99%) versus 83% (95% CI 74–90%), p = 0.0007. Effect of period of study is significant when using multivariate analysis on PFS and OS and lactate dehydrogenase level (PFS and OS) and age (OS). These data from everyday practice confirm the benefit for patients with FL treated in the last decade through availability of rituximab in first line used alone or in association with various chemotherapy regimens. Copyright

A phase II study of the oral JAK1/JAK2 inhibitor ruxolitinib in advanced relapsed/refractory Hodgkin lymphoma

JAK2 constitutive activation/overexpression is common in classical Hodgkin lymphoma, and several cytokines stimulate Hodgkin lymphoma cells by recognizing JAK1-/JAK2-bound receptors. JAK blockade may thus be therapeutically beneficial in Hodgkin lymphoma. In this phase II study we assessed the safety and efficacy of ruxolitinib, an oral JAK1/2 inhibitor, in patients with relapsed/refractory Hodgkin lymphoma. The primary objective was overall response rate according to the International Harmonization Project 2007 criteria. Thirty-three patients with advanced disease (median number of prior lines of treatment: 5; refractory: 82%) were included; nine (27.3%) received at least six cycles of ruxolitinib and six (18.2%) received more than six cycles. The overall response rate after six cycles was 9.4% (3/32 patients). All three responders had partial responses; another 11 patients had transient stable disease. Best overall response rate was 18.8% (6/32 patients). Rapid alleviation of B-symptoms was common. The median duration of response was 7.7 months, median progression-free survival 3.5 months (95% CI: 1.9–4.6), and the median overall survival 27.1 months (95% CI: 14.4–27.1). Forty adverse events were reported in 14/33 patients (42.4%). One event led to treatment discontinuation, while 87.5% of patients recovered without sequelae. Twenty-five adverse events were grade 3 or higher. These events were mostly anemia (n=11), all considered related to ruxolitinib. Other main causes of grade 3 or higher adverse events included lymphopenia and infections. Of note, no cases of grade 4 neutropenia or thrombocytopenia were observed. Ruxolitinib shows signs of activity, albeit short-lived, beyond a simple anti-inflammatory effect. Its limited toxicity suggests that it has the potential to be combined with other therapeutic modalities. ClinicalTrials.gov: NCT01877005

A new signaling cascade linking BMP4, BMPR1A, ΔNp73 and NANOG impacts on stem-like human cell properties and patient outcome

In a significant number of cases cancer therapy is followed by a resurgence of more aggressive tumors derived from immature cells. One example is acute myeloid leukemia (AML), where an accumulation of immature cells is responsible for relapse following treatment. We previously demonstrated in chronic myeloid leukemia that the bone morphogenetic proteins (BMP) pathway is involved in stem cell fate and contributes to transformation, expansion, and persistence of leukemic stem cells. Here, we have identified intrinsic and extrinsic dysregulations of the BMP pathway in AML patients at diagnosis. BMP2 and BMP4 protein concentrations are elevated within patients’ bone marrow with a BMP4-dominant availability. This overproduction likely depends on the bone marrow microenvironment, since MNCs do not overexpress BMP4 transcripts. Intrinsically, the receptor BMPR1A transcript is increased in leukemic samples with more cells presenting this receptor at the membrane. This high expression of BMPR1A is further increased upon BMP4 exposure, specifically in AML cells. Downstream analysis demonstrated that BMP4 controls the expression of the survival factor ΔNp73 through its binding to BMPR1A. At the functional level, this results in the direct induction of NANOG expression and an increase of stem-like features in leukemic cells, as shown by ALDH and functional assays. In addition, we identified for the first time a strong correlation between ΔNp73, BMPR1A and NANOG expression with patient outcome. These results highlight a new signaling cascade initiated by tumor environment alterations leading to stem-cell features and poor patients’ outcome.