Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in western countries, with an incidence of approximately 5.1/100,000 new cases per year. Some patients may never require ...treatment, whereas others relapse early after front line therapeutic approaches. Recent whole genome and whole exome sequencing studies have allowed a better understanding of CLL pathogenesis and the identification of genetic lesions with potential clinical relevance. Consistently, precision medicine plays a pivotal role in the treatment algorithm of CLL, since the integration of molecular biomarkers with the clinical features of the disease may guide treatment choices. Most CLL patients present at the time of diagnosis with an early stage disease and are managed with a watch and wait strategy. For CLL patients requiring therapy, the CLL treatment armamentarium includes both chemoimmunotherapy strategies and biological drugs. The efficacy of these treatment strategies relies upon specific molecular features of the disease.
disruption (including both
mutation and 17p deletion) is the strongest predictor of chemo-refractoriness, and the assessment of
status is the first and most important decisional node in the first line treatment algorithm. The presence of
disruption mandates treatment with biological drugs that inhibit the B cell receptor or, alternatively, the B-cell lymphoma 2 (BCL2) pathway and can, at least in part, circumvent the chemorefractoriness of
-disrupted patients. Beside
disruption, the mutational status of immunoglobulin heavy variable (IGHV) genes also helps clinicians to improve treatment tailoring. In fact, patients carrying mutated IGHV genes in the absence of
disruption experience a long-lasting and durable response to chemoimmunotherapy after fludarabine, cyclophosphamide, and rituximab (FCR) treatment with a survival superimposable to that of a matched general population. In contrast, patients with unmutated IGHV genes respond poorly to chemoimmunotherapy and deserve treatment with B cell receptor inhibitors. Minimal residual disease is also emerging as a relevant biomarker with potential clinical implications. Overall, precision medicine is now a mainstay in the management and treatment stratification of CLL. The identification of novel predictive biomarkers will allow further improvements in the treatment tailoring of this leukemia.
Here we evaluated the epigenomic and transcriptomic profile of XPO1 mutant chronic lymphocytic leukaemia (CLL) and their clinical phenotype. By ATAC-seq, chromatin regions that were more accessible ...in XPO1 mutated CLL were enriched of binding sites for transcription factors regulated by pathways emanating from the B-cell receptor (BCR), including NF-κB signalling, p38-JNK and RAS-RAF-MEK-ERK. XPO1 mutant CLL, consistent with the chromatin accessibility changes, were enriched with transcriptomic features associated with BCR and cytokine signalling. By combining epigenomic and transcriptomic data, MIR155HG, the host gene of miR-155, and MYB, the transcription factor that positively regulates MIR155HG, were upregulated by RNA-seq and their promoters were more accessible by ATAC-seq. To evaluate the clinical impact of XPO1 mutations, we investigated a total of 957 early-stage CLL subdivided into 3 independent cohorts (N = 276, N = 286 and N = 395). Next-generation sequencing analysis identified XPO1 mutations as a novel predictor of shorter time to first treatment (TTFT) in all cohorts. Notably, XPO1 mutations maintained their prognostic value independent of the immunoglobulin heavy chain variable status and early-stage prognostic models. These data suggest that XPO1 mutations, conceivably through increased miR-155 levels, may enhance BCR signalling leading to higher proliferation and shorter TTFT in early-stage CLL.
SHOX haploinsufficiency causes 70-90% of Léri-Weill dyschondrosteosis (LWD) and 2-10% of idiopathic short stature (ISS). Deletions removing the entire gene or enhancers and point mutations in the ...coding region represent a well-established cause of haploinsufficiency. During diagnostic genetic testing on ISS/LWD patients, in addition to classic SHOX defects, five 5'UTR variants (c.-58G > T, c.-55C > T, c.-51G > A, c.-19G > A, and c.-9del), were detected whose pathogenetic role was unclear and were thus classified as VUS (Variants of Uncertain Significance). The purpose of the present study was to investigate the role of these noncoding variations in SHOX haploinsufficiency. The variants were tested for their ability to interfere with correct gene expression of a regulated reporter gene (luciferase assay). The negative effect on the mRNA splicing predicted in silico for c.-19G > A was assayed in vitro through a minigene splicing assay. The luciferase assay showed that c.-51G > A, c.-19G > A, and c.-9del significantly reduce luciferase activity by 60, 35, and 40% at the homozygous state. Quantification of the luciferase mRNA showed that c.-51G > A and c.-9del might interfere with the correct SHOX expression mainly at the post-transcriptional level. The exon trapping assay demonstrated that c.-19G > A determines the creation of a new branch site causing an aberrant mRNA splicing. In conclusion, this study allowed us to reclassify two of the 5'UTR variants identified during SHOX diagnostic screening as likely pathogenic, one remains as a VUS, and two as likely benign variants. This analysis for the first time expands the spectrum of the genetic causes of SHOX haploinsufficiency to noncoding variations in the 5'UTR.
Myelodysplastic syndromes (MDS) arising in the context of inherited bone marrow failure syndromes (IBMFS) differ in terms of prognosis and treatment strategy compared to MDS occurring in the adult ...population without an inherited genetic predisposition. The main molecular pathways affected in IBMFS involve telomere maintenance, DNA repair, biogenesis of ribosomes, control of proliferation and others. The increased knowledge on the genes involved in MDS pathogenesis and the wider availability of molecular diagnostic assessment have led to an improvement in the detection of IBMFS genetic predisposition in MDS patients. A punctual recognition of these disorders implies a strict surveillance of the patient in order to detect early signs of progression and promptly offer allogeneic hematopoietic stem cell transplantation, which is the only curative treatment. Moreover, identifying an inherited mutation allows the screening and counseling of family members and directs the choice of donors in case of need for transplantation. Here we provide an overview of the most recent data on MDS with genetic predisposition highlighting the main steps of the diagnostic and therapeutic management. In order to highlight the pitfalls of detecting IBMFS in adults, we report the case of a 27-year-old man affected by MDS with an underlying telomeropathy.
Aim: The aim of the current study was to evaluate the potential clinical impact of clonal evolution detected by fluorescence in situ hybridization (FISH) in untreated chronic lymphocytic leukaemia ...(CLL) patients managed with a watch-and-wait strategy.
Methods: We performed both overall survival (OS) and time to first treatment (TTFT) analysis. For the first one, we exploited a real-life cohort of 123 consecutive CLL patients followed at our institution, for which at least a second FISH evaluation during watch and wait was available. For TTFT analysis, we considered only patients treated after the second FISH sample (n = 69).
Results: Considering the original cohort, patients who acquired a FISH abnormality displayed a worse outcome with a median OS of 91.9 months compared to 147.3 months for patients who did not acquire any FISH abnormalities (P = 0.007). Unmutated immunoglobulin heavy chain gene (IGHV) genes were associated with a higher probability of acquiring a FISH abnormality (P = 0.04). Turning to TTFT analysis, patients who gained at least one FISH abnormality (n = 7, 10%) were characterised by an earlier treatment requirement with a median TTFT of 1.1 months, compared to 2.7 months in patients who did not acquire any FISH abnormalities (n = 62, 90%) (P = 0.025).
Conclusions: The dynamic acquisition of karyotypic abnormalities by FISH predicts poor outcomes and early treatment requirement in CLL patients. Our results suggest that FISH analysis could be integrated with other clinical and biological features to obtain dynamic scores that are able to predict outcomes at different phases of disease history.
Summary
Richter syndrome (RS) is mostly due to the direct transformation of the chronic lymphocytic leukaemia (CLL) clone, as documented by the same immunoglobulin heavy‐chain variable region (IGHV) ...rearrangement in both CLL and RS cells. In rare cases characterized by a better outcome, the RS clone harbours a different IGHV rearrangement compared to the CLL phase. We investigated the CLL phase of clonally unrelated RS to test whether the RS clone was already identifiable prior to clinicopathologic transformation, albeit undetectable by conventional approaches. CLL cells of eight patients with unrelated RS were subjected to an ultra‐deep next‐generation sequencing (NGS) approach with a sensitivity of 10−6. In 7/8 cases, the RS rearrangement was not identified in the CLL phase. In one case, the RS clone was identified at a very low frequency in the CLL phase, conceivably due to the concomitance of CLL sampling and RS diagnosis. Targeted resequencing revealed that clonally unrelated RS carries genetic lesions primarily affecting the TP53, MYC, ATM and NOTCH1 genes. Conversely, mutations frequently involved in de novo diffuse large B‐cell lymphoma (DLBCL) without a history of CLL were absent. These results suggest that clonally unrelated RS is a truly de novo lymphoma with a mutational profile reminiscent, at least in part, of clonally related RS.
Acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) represent an unmet clinical need whose prognosis is still dismal. Alterations of immune response play a prominent role in AML/MDS ...pathogenesis, revealing novel options for immunotherapy. Among immune system regulators, CD47, immune checkpoints, and toll-like receptor 2 (TLR2) are major targets. Magrolimab antagonizes CD47, which is overexpressed by AML and MDS cells, thus inducing macrophage phagocytosis with clinical activity in AML/MDS. Sabatolimab, an inhibitor of T-cell immunoglobulin and mucin domain-containing protein 3 (TIM3), which disrupts its binding to galectin-9, has shown promising results in AML/MDS, enhancing the effector functions of lymphocytes and triggering tumor cell death. Several other surface molecules, namely CD33, CD123, CD45, and CD70, can be targeted with monoclonal antibodies (mAbs) that exert different mechanisms of action and include naked and conjugated antibodies, bispecific T-cell engagers, trispecific killer engagers, and fusion proteins linked to toxins. These novel mAbs are currently under investigation for use as monotherapy or in combination with hypomethylating agents, BCL2 inhibitors, and chemotherapy in various clinical trials at different phases of development. Here, we review the main molecular targets and modes of action of novel mAb-based immunotherapies, which can represent the future of AML and higher risk MDS treatment.
Summary
We aimed at molecularly dissecting the anatomical heterogeneity of small lymphocytic lymphoma (SLL), by analysing a cohort of 12 patients for whom paired DNA from a lymph node biopsy and ...circulating cells, as well as plasma‐circulating tumour DNA (ctDNA) was available. Notably, the analyses of the lymph node biopsy and of circulating cells complement each other since a fraction of mutations (20·4% and 36·4%, respectively) are unique to each compartment. Plasma ctDNA identified two additional unique mutations. Consistently, the different synchronous sources of tumour DNA complement each other in informing on driver gene mutations in SLL harbouring potential prognostic and/or predictive value.
Hepatitis B virus reactivation (HBVr) can develop in HBV surface antigen (HBsAg) positive or HBsAg-negative and anti-hepatitis B core antigen antibodies (anti-HBc) positive (past HBV infection) ...patients receiving immuno-chemotherapy for hematological malignancies. A higher rate of HBVr is associated with the use of rituximab (R) in patients with past HBV infection, thus justifying an antiviral prophylaxis. In this study we evaluated the incidence of HBVr in a real-life cohort of 362 anti-HBc-positive subjects affected by non-Hodgkin lymphoma (NHL), mainly receiving lamivudine (LAM) prophylaxis (93%) and all undergoing a R-containing regimen. A retrospective, multicenter, observational study was conducted in 4 Italian Hematology Departments. The primary endpoint was the incidence of virologic (HBV DNA-positive), serologic (HBsAg-positive) and clinical (ALT increase > 3 × upper limit of normal) HBVr, which occurred in five, four and one patients, respectively, with a total HBVr rate of 1.4%. None of them had to discontinue the chemotherapy program, while two patients required a delay. Treatment-related adverse events (AEs) were reported during LAM prophylaxis in three patients (0.9%). In conclusion, this study confirms the efficacy and safety of LAM prophylaxis in anti-HBc-positive patients undergoing R-containing regimens.
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