Do PD-1 and PD-L2 expressions have prognostic impact in hematologic malignancies?

B7-H3 in acute myeloid leukemia: From prognostic biomarker to immunotherapeutic target

ABSTRACT

B7-H3 (CD276), an immune checkpoint protein of the B7 family, exhibits significant upregulation in solid tumors and hematologic malignancies, exerting a crucial role in their pathophysiology. The distinct differential expression of B7-H3 between tumors and normal tissues and its multifaceted involvement in tumor pathogenesis position it as a promising therapeutic target for tumors. In the context of acute myeloid leukemia (AML), B7-H3 is prominently overexpressed and closely associated with unfavorable prognoses, yet it has remained understudied. Despite various ongoing clinical trials demonstrating the potential efficacy of immunotherapies targeting B7-H3, the precise underlying mechanisms responsible for B7-H3-mediated proliferation and immune evasion in AML remain enigmatic. In view of this, we comprehensively outline the current research progress concerning B7-H3 in AML, encompassing in-depth discussions on its structural attributes, receptor interactions, expression profiles, and biological significance in normal tissues and AML. Moreover, we delve into the protumor effects of B7-H3 in AML, examine the intricate mechanisms that underlie its function, and discuss the emerging application of B7-H3-targeted therapy in AML treatment. By juxtaposing B7-H3 with other molecules within the B7 family, this review emphasizes the distinctive advantages of B7-H3, not only as a valuable prognostic biomarker but also as a highly promising immunotherapeutic target in AML.

Comparison of monoclonal antibodies targeting CD38, SLAMF7 and PD-1/PD-L1 in combination with Bortezomib/Immunomodulators plus dexamethasone/prednisone for the treatment of multiple myeloma: an indirect-comparison Meta-analysis of randomised controlled trials

Background

Many clinical trials have assessed the effect and safety of monoclonal antibodies (MAbs) in combination with proteasome inhibitors or immunomodulators plus dexamethasone/prednisone for the treatment of multiple myeloma (MM). The treatment outcomes of comparing different MAbs in combination with the above-mentioned agents remained unclear. We performed the meta-analysis to indirectly compare the effect and safety of MAbs targeting CD38, SLAMF7, and PD-1/PD-L1 in combination with bortezomib/immunomodulators plus dexamethasone/prednisone for patients with MM.

Methods

We searched thoroughly in the databases for randomised controlled trials (RCTs) in which at least one of the three MAbs were included. We included eleven eligible RCTs with 5367 patients in the meta-analysis. Statistical analysis was carried out using StataMP14 and Indirect Treatment Comparisons software.

Results

We calculated hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS) and relative risk (RR) for overall response rate, complete response (CR) or better, very good partial response (VGPR) or better, VGPR, partial response, stable disease, and grade 3 or higher adverse events among the three groups. The HRs for PFS of the CD38 group vs SLAMF7 group, CD38 group vs PD-1/PD-L1 group, and SLAMF7 group vs PD-1/PD-L1 group were 0.662 (95%CI 0.543–0.806), 0.317 (95%CI 0.221–0.454), and 0.479 (95%CI 0.328–0.699), respectively. The HR for OS of the CD38 group vs SLAMF7 group was 0.812 (95%CI 0.584–1.127). The RR for CR or better in the CD38 group vs SLAMF7 group was 2.253 (95%CI 1.284–3.955). The RR for neutropenia of the CD38 group vs SLAMF7 group was 1.818 (95%CI 1.41–2.344).

Conclusions

Treatment with the CD38 group had longer PFS and better treatment response than that with the SLAMF7 or PD-1/PD-L1 group. In addition, the SLAMF7 group prolonged PFS compared with the PD-1/PD-L1 group and was associated with a lower incidence of grade 3 or higher neutropenia than the CD38 and PD-1/PD-L1 group. In conclusion, MAbs targeting CD38 are the best, followed by those targeting SLAMF7; MAbs targeting PD-1/PD-L1 are the worst when in combination with bortezomib/immunomodulators plus dexamethasone/prednisone for the treatment of MM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08588-9.

B7 Family Members in Lymphoma: Promising Novel Targets for Tumor Immunotherapy?

T cells play a vital role in the immune responses against tumors. Costimulatory or coinhibitory molecules regulate T cell activation. Immune checkpoint inhibitors, such as programmed cell death protein 1 (PD-1) and programmed death ligand 1 (PD-L1) have shown remarkable benefits in patients with various tumor, but few patients have displayed significant immune responses against tumors after PD-1/PD-L1 immunotherapy and many have been completely unresponsive. Thus, researchers must explore novel immune checkpoints that trigger durable antitumor responses and improve clinical outcomes. In this regard, other B7 family checkpoint molecules have been identified, namely PD-L2, B7-H2, B7-H3, B7-H4 and B7-H6. The aim of the present article was to address the expression, clinical significance and roles of B7 family molecules in lymphoma, as well as in T and NK cell-mediated tumor immunity. B7 family checkpoints may offer novel and immunotherapeutic strategies for patients with lymphoma.

Checkpoint Inhibitors and Engineered Cells: New Weapons for Natural Killer Cell Arsenal Against Hematological Malignancies

Natural killer (NK) cells represent one of the first lines of defense against malignant cells. NK cell activation and recognition are regulated by a balance between activating and inhibitory receptors, whose specific ligands can be upregulated on tumor cells surface and tumor microenvironment (TME). Hematological malignancies set up an extensive network of suppressive factors with the purpose to induce NK cell dysfunction and impaired immune-surveillance ability. Over the years, several strategies have been developed to enhance NK cells-mediated anti-tumor killing, while other approaches have arisen to restore the NK cell recognition impaired by tumor cells and other cellular components of the TME. In this review, we summarize and discuss the strategies applied in hematological malignancies to block the immune check-points and trigger NK cells anti-tumor effects through engineered chimeric antigen receptors.