Mature aggressive B-cell lymphoma across age groups - molecular advances and therapeutic implications

The kava chalcone flavokawain B exerts inhibitory activity and synergizes with BCL-2 inhibition in malignant B-cell lymphoma

BACKGROUND

B-cell lymphoma, which originates from B cells at diverse differentiation stages, is the most common non-Hodgkin lymphoma with tremendous treatment challenges and unsatisfactory clinical outcomes. Flavokawain B (FKB), a naturally occurring chalcone extracted from kava, possesses promising anticancer properties. However, evidence on the effects of FKB on hematological malignancies, particularly lymphomas, remains scarce.

PURPOSE

This study aimed to investigate the antilymphoma effect of FKB and its underlying mechanisms.

STUDY DESIGN/METHODS

Proliferation assays, flow cytometry, and western blotting were employed to determine whether and how FKB affected B-cell lymphoma cell lines in vitro. Xenograft mouse models were established to evaluate the antilymphoma efficacy of FKB in vivo.

RESULTS

FKB reduced the viability of a panel of B-cell lymphoma cell lines in a dose- and time-dependent manner. Mitochondrial apoptosis was markedly induced by FKB, as evidenced by an increased percentage of annexin V-positive cells, a loss of mitochondrial membrane potential, and cleavage of caspase-3 and PARP. Moreover, FKB inhibited BCL-XL expression and synergized with the BCL-2 inhibitor ABT-199. Mechanistically, FKB treatment decreased the phosphorylation of Akt, mammalian target of rapamycin (mTOR), glycogen synthase kinase-3β (GSK3β), and ribosomal protein S6 (RPS6). Pharmacological blockage of phosphoinositide 3-kinase (PI3K), Akt, or GSK3β potentiated the activity of FKB, indicating the involvement of the PI3K/Akt cascade in FKB-mediated inhibitory effects. In mouse xenograft models, the intraperitoneal administration of FKB significantly decreased lymphoma growth, accompanied by diminished mitosis and Ki-67 staining of tumor tissues.

CONCLUSION

Our data demonstrate the robust therapeutic potential of FKB in the treatment of B-cell lymphoma.

An immune risk score predicts survival of patients with diffuse large B-cell lymphoma

PURPOSE

Providing accurate prognostic models is necessary for diffuse large B-cell lymphoma, but there are still many uncertainties. So far, none of the models include immune cells. Therefore, an immune risk score was constructed to predict the survival of patients.

METHODS

CIBERSORTx was chosen to estimate the proportion of 22 human immune cell subsets from public datasets and generate an immune risk score to predict patients' survival in a training cohort using the least absolute shrinkage and selection operator (LASSO) Cox regression model.

RESULTS

The prognostic model had high predictive ability in the training and validation cohorts. Subjects in the training cohort with high scores had a worse prognosis compared with subjects with low scores. The same result was also found in the three validation cohorts. Multivariable analysis suggested that the immune risk score was an independent prognostic factor. The merged score, including the immune risk score and the international prognostic index (IPI) risk category, had better predictive accuracy.

CONCLUSIONS

Our immune risk score promises to be a complement to current prognostic models.

Overview of Targeted Drugs for Mature B-Cell Non-hodgkin Lymphomas

The improved knowledge of pathogenetic mechanisms underlying lymphomagenesis and the discovery of the critical role of tumor microenvironments have enabled the design of new drugs against cell targets and pathways. The Food and Drug Administration (FDA) has approved several monoclonal antibodies (mAbs) and small molecule inhibitors (SMIs) for targeted therapy in hematology. This review focuses on the efficacy results of the currently available targeted agents and recaps the main ongoing trials in the setting of mature B-Cell non-Hodgkin lymphomas. The objective is to summarize the different classes of novel agents approved for mature B-cell lymphomas, to describe in synoptic tables the results they achieved and, finally, to draw future scenarios as we glimpse through the ongoing clinical trials. Characteristics and therapeutic efficacy are summarized for the currently approved mAbs [i.e., anti-Cluster of differentiation (CD) mAbs, immune checkpoint inhibitors, chimeric antigen receptor (CAR) T-cell therapy, and bispecific antibodies] as well as for SMIs i.e., inhibitors of B-cell receptor signaling, proteasome, mTOR BCL-2 HDAC pathways. The biological disease profiling of B-cell lymphoma subtypes may foster the discovery of innovative drug strategies for improving survival outcome in lymphoid neoplasms, as well as the trade-offs between efficacy and toxicity. The hope for clinical advantages should carefully be coupled with mindful awareness of the potential pitfalls and the occurrence of uneven, sometimes severe, toxicities.

The possible role of maintenance treatment for primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare and aggressive brain tumor. The prognosis is poor, with high rates of relapse and disease progression after treatment. In addition, PCNSL affects a largely older population, so that a significant proportion of patients are ineligible for intensive therapies and high-dose chemotherapy. The elderly patients are also susceptible to the accelerated and detrimental cognitive side effects of whole-brain irradiation which is an alternative consolidation to high-dose chemotherapy. Maintenance therapy has been shown to be a promising strategy to prolong remission time in other hematopoietic malignancies. Herein, we discuss the place of maintenance treatment in PCNSL in view of perspective obtained from hematological malignancies and non-Hodgkin's lymphoma.