The expression of CD38 by B cells chronic lymphocytic leukemia (B-CLL) was studied in 20 untreated patients. The cells expressed abundant CD38 (relative fluorescence intensity range, 6 to 15) in 6 cases (group I patients), whereas CD38 expression was low to absent (relative fluorescence intensity range, 0 to 3) in the remaining cases (group II patients). Exposure of the cells from group I patients to goat antihuman mu chain antibodies (Ga mu-ab) resulted in the elevation of intracellular free Ca2+ concentration([Ca2+]i) followed by apoptosis. In contrast, exposure of group II cells to Ga mu-ab was not followed by increased levels of [Ca2+]i, programmed cell death or cell proliferation. No differences in the expression of surface IgM were noted in the two groups of B-CLL cells. Normal peripheral blood B cells, which expressed low to absent CD38, were capable of mobilizing [Ca2+]i and of proliferating after exposure to Ga mu-ab. The collected data suggest that, although group I B-CLL cells were able to transduce the signals delivered by IgM crosslinking, this pathway was severely impaired in group II B-CLL cells. However, unlike that observed in normal circulating B cells, stimulation of group I cells with Ga mu-ab resulted in apoptosis rather than proliferation. CD38 did not appear to be directly involved in [Ca2+]i mobilization induced by Ga mu-ab in group I B-CLL cells because their exposure to anti-CD38 monoclonal antibodies failed to cause [Ca2+]i mobilization or to block the [Ca2+]i response induced by Ga mu-ab. These data indicate that CD38 expression identified a particular subset of B-CLL cells with defined functional properties, including the propensity to undergo apoptosis.
Background The management of non-small cell lung cancer (NSCLC) has become increasingly complex due to the evolution of personalized medicine approaches. Such approaches are characterized by the necessity of adequate tumor samples; hence, improved biopsy techniques are needed. Transbronchial lung cryobiopsy is a novel endoscopic procedure designed to collect peripheral pulmonary tissue, and it is currently employed in interstitial lung diseases. The use of this technique in oncology might result in improved mediastinum staging and molecular characterizations; however, available data involving the use of a cryoprobe on mediastinal lymph nodes are still limited. Case presentation Here we present a series of five consecutive patients who underwent endoscopic assessment of mediastinal lymph nodes for oncologic reasons. All patients were subjected both to endobronchial ultrasound-guided transbronchial needle aspiration (EBUS TBNA) and cryobiopsy of mediastinal lymph nodes during the same procedure, and no complications were observed. In three of the reported cases, both cryobiopsy and cell block from EBUS TBNA were positive, while in one case cryobiopsy was not diagnostic and EBUS TBNA was negative; moreover, one case showed discordance between the procedures, as cryobiopsy was negative and cell block obtained from multiple stations was diagnostic for small cell lung cancer. In one case involving a patient treated for lymphoma, cryobiopsy provided more complete histologic characterization, and in another case involving a patient affected by NSCLC cryobiopsy provided more material for molecular analyses. Conclusion This case presentation series suggests that cryobiopsy, which has been generally used on peripheral lung lesions so far, is a feasible and safe approach for diagnosis and staging of mediastinal lymph nodal involvement, especially when station 7 is involved. Compared to EBUS TBNA, cryobiopsy might provide more adequate histological samples, with a possible impact on molecular characterizations and, therefore, therapeutic decisions. However, the learning curve of the procedure has not to be understated and optimal protocols for implementing this technique are needed. In our opinion, further studies designed to integrate the routine use of cryobiopsy in current practice for solid and eventually hematologic tumors with mediastinal lymph node involvement are warranted.
Chronic lymphocytic leukaemia (CLL) is characterised by a heterogeneous clinical course. Such heterogeneity is associated with a number of markers, including TP53 gene inactivation. While TP53 gene alterations determine resistance to chemotherapy, it is not clear whether they can influence early disease progression. To clarify this issue, TP53 mutations and deletions of the corresponding locus [del(17p)] were evaluated in 469 cases from the O-CLL1 observational study that recruited a cohort of clinically and molecularly characterised Binet stage A patients. Twenty-four cases harboured somatic TP53 mutations [accompanied by del(17p) in 9 cases], 2 patients had del(17p) only, and 5 patients had TP53 germ-line variants. While del(17p) with or without TP53 mutations was capable of significantly predicting the time to first treatment, a reliable measure of disease progression, TP53 mutations were not. This was true for cases with high or low variant allele frequency. The lack of predictive ability was independent of the functional features of the mutant P53 protein in terms of transactivation and dominant negative potential. TP53 mutations alone were more frequent in patients with mutated IGHV genes, whereas del(17p) was associated with the presence of adverse prognostic factors, including CD38 positivity, unmutated-IGHV gene status, and NOTCH1 mutations.
Previously, we demonstrated that B-chronic lymphocytic leukemia (B-CLL) cells could be divided into 2 groups depending on the expression of CD38 by the malignant cells. The 2 groups differed in their signal-transducing capacities initiated by cross-linking of surface IgM; only in CD38-positive cells was an efficient signal delivered, invariably resulting in cell apoptosis. In this study, we investigated the effect of surface IgD cross-linking in 10 patients with CD38-positive B-CLL. Exposure of the malignant cells to goat antihuman δ-chain antibodies (Gaδ-ab) caused [Ca++]i mobilization and tyrosine kinase phosphorylation in a manner not different from that observed after goat antihuman μ-chain antibody (Gaμ-ab) treatment in vitro. However, Gaδ-ab-treated cells failed to undergo apoptosis and instead displayed prolonged survival in culture and differentiated into plasma cells when rIL2 was concomitantly present. Cross-linking of surface IgD failed to induce proliferation of the malignant cells in vitro. Moreover, treatment with Gaδ-ab did not prevent apoptosis of B-CLL cells induced by Gaμ-ab. Collectively, these experiments demonstrated that IgM and IgD expressed by the same cell may deliver opposite signals under particular circumstances and provide some clues for the understanding of the pathophysiology of B-CLL.
Introduction. Patients with TP53 dysfunction, assessed by del(17p) or TP53 mutations, respond poorly to chemo-immunotherapy and fare better with the new therapies (BCR and BCL-2 inhibitors); however, it is unclear whether their response is similar to that of patients without anomalies or whether there is currently an adequate determination of TP53 dysfunction. Area covered.A literature search was undertaken on clinical trials and real-world experience data on patients with TP53 dysfunction treated with different protocols. Moreover, data on the TP53 biological function and on the tests currently employed for its assessment were reviewed. Expert opinion.Although TP53 dysfunction has less negative influence on the new biological therapies, patients with these alterations, particularly those with biallelic inactivation of TP53, have a worst outcome with these therapies than those without alterations. At present, a determination of TP53, particularly with next generation sequencing (NGS) methodologies, may be sufficient for the identifications of the patients unsuitable for chemo-immunotherapy, although integration with del(17p) would be advisable. For the future, more extensive determinations of the TP53 status, including functional assays, may become part of the current armamentarium for a better patient stratification and treatment with newer protocols.
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