Immunotherapy of Lymphoma and Myeloma: Facts and Hopes

Safety and efficacy of PD-1 and PD-L1 inhibitors in relapsed and refractory Hodgkin's lymphoma: a systematic review and meta-analysis of 20 prospective studies

BACKGROUND

Inhibitors of programmed cell death protein 1 (PD-1) and programmed cell death ligand 1 (PD-L1) have been used in the treatment of relapsed and refractory Hodgkin's lymphoma (R/R HL) recently. To further understand the safety and efficacy of PD-1/PD-L1 inhibitors in R/R HL, we conducted this meta-analysis.

METHODS

Databases and the Clinical Registration Platforms have been systematically searched for related studies by March 2022. For safety analysis, the incidence and exhibition of any grade and grade 3 or higher adverse effects (AEs) were evaluated. Besides, severe AEs (SAEs), treatment-related deaths, and AEs leading to treatment discontinuation were summarized. The overall response rate (ORR), complete response (CR) rate, partial response (PR) rate, progression-free survival (PFS), overall survival (OS), and duration of response (DOR) were calculated for efficacy analysis. All processes were implemented mainly through the package Meta and MetaSurv of software R 4.1.2.

RESULTS

Overall 20 studies and 1440 patients were enrolled. The pooled incidence of any grade and grade 3 or higher AEs were 92% and 26%, respectively. The pooled ORR, CR rate and PR rate were 79%, 44% and 34%, respectively. The most common AEs were neuropathy (29%), nausea (27%), pyrexia (26%), and leukopenia (25%), and the most common grade 3 or higher AEs included leukopenia (10%), infusion reaction (8%), weight gain (3%), and neutropenia (2.7%). In survival analysis, pembrolizumab monotherapy appeared to perform better compared to nivolumab monotherapy.

CONCLUSIONS

PD-1/PD-L1 inhibitors show promising efficacy and tolerable AEs in the treatment of R/R HL.

Risk and prognosis of secondary breast cancer after radiation therapy for non-Hodgkin lymphoma: a massive population-based analysis

PURPOSE

One of the best ways to control non-Hodgkin lymphoma (NHL) locally is radiation therapy (RT), which is a crucial component of care for many patients. There has not been any research on the risk and prognosis of secondary breast cancer (SBC) in females with NHL receiving RT.

METHODS

In our study, females with NHL as their initial cancer diagnosis were included from 1975 to 2018 in the Surveillance, Epidemiology and End Results (SEER) database. Using Fine and Gray's competing risk regression assess the cumulative incidence of SBC. The standardized incidence ratios (SIR) and radiation-attributed risk (RR) for SBC were assessed using Poisson regression analysis. We evaluated the overall survival (OS) of SBC patients using the Kaplan-Meier technique.

RESULTS

Of the 41,983 females with NHL, 10,070 received RT and 320 (3.18%) developed SBC. 31,913 females did not receive RT and 805 (2.52%) developed SBC. RT was significantly related with a greater chance of acquiring SBC in the Fine-Gray competing risk regression (adjusted hazard ratios (HR) = 1.14; 95% confidence intervals (CI), 1.09-1.30; P = 0.011). When an NHL diagnosis was made at an older age, the dynamic SIR and RR for SBC also declined over time. Regarding general survivability, there was not statistically significant (P = 0.970) after propensity score matching (PSM).

CONCLUSIONS

RT is an independent risk factor for SBC in females with NHL. Special attention should be paid to the monitoring of breast cancer indicators in them, especially young.

Immunotherapy approaches for hematological cancers

Hematological cancers such as leukemia, lymphoma, and multiple myeloma have traditionally been treated with chemo and radiotherapy approaches. Introduction of immunotherapies for treatment of these diseases has led to patient remissions that would not have been possible with traditional approaches. In this critical review we identify main disease characteristics, symptoms, and current treatment options. Five common immunotherapies, namely checkpoint inhibitors, vaccines, cell-based therapies, antibodies, and oncolytic viruses, are described, and their applications in hematological cancers are critically discussed.

PD‐L1 expression in peripheral blood granulocytes at diagnosis as prognostic factor in classical Hodgkin lymphoma

Hodgkin lymphoma (HL) is a neoplastic disease in which the inflammatory microenvironment plays a pivotal role in the tumorigenesis. Neutrophilia is a typical finding in HL at diagnosis and, in particular, in association with lymphocytopenia, is a negative prognostic factor. As the immune checkpoint Programmed Death (PD)‐L1/PD‐1 has become an important therapeutic target, we were interested in the expression of PD‐L1 in peripheral blood (PB) leukocytes using flow cytometry and RT‐PCR in patients with HL and healthy controls. Granulocytes were the major PB cell fraction expressing PD‐L1. PD‐L1 expression on granulocytes was higher in patients with HL than in controls and correlated with lower T‐cell numbers in PB. We analyzed for associations between PD‐L1 expression in PB granulocytes at the time of diagnosis with patient characteristics and outcome in 126 patients with HL treated with standard chemotherapy adriamycin, bleomycin, vinblastine, and dacarbazine. Increased PD‐L1 expression in PB associated with advanced disease, systemic symptoms, positive interim positron emission tomography, and inferior progression‐free survival (PFS). PFS at 4 years was 81% (95% C.I., 71–87%) in patients with normal PD‐L1 expression and 56% (95% C.I., 35–72%) in patients with higher‐than‐normal PD‐L1 expression (p = 0.002). In conclusion, PD‐L1 expression in PB could become a potentially actionable prognostic factor in HL.

PET Imaging for Hematologic Malignancies

Hematologic malignancies are a broad category of cancers arising from the lymphoid and myeloid cell lines. The 2016 World Health Organization classification system incorporated molecular markers as part of the diagnostic criteria and includes more than 100 subtypes. This article focuses on the subtypes for which imaging with positron emission tomography/computed tomography (PET/CT) has become an integral component of the patient's evaluation, that is, lymphoma and multiple myeloma. Leukemia and histiocytic and dendritic cell neoplasms are also discussed as these indications for PET/CT are less common, but increasingly seen in clinic.

Prospects and Challenges for T Cell-Based Therapies of HCC

The scope of therapeutic options for the treatment of hepatocellular carcinoma (HCC) has recently been expanded by immunotherapeutic regimens. T cell-based therapies, especially in combination with other treatments have achieved far better outcomes compared to conventional treatments alone. However, there is an emerging body of evidence that eliciting T cell responses in immunotherapeutic approaches is insufficient for favorable outcomes. Immune responses in HCC are frequently attenuated in the tumor microenvironment (TME) or may even support tumor progress. Hence, therapies with immune checkpoint inhibitors or adoptive cell therapies appear to necessitate additional modification of the TME to unlock their full potential. In this review, we focus on immunotherapeutic strategies, underlying molecular mechanisms of CD8 T cell immunity, and causes of treatment failure in HCC of viral and non-viral origin. Furthermore, we provide an overview of TME features in underlying etiologies of HCC patients that mediate therapy resistance to checkpoint inhibition and discuss strategies from the literature concerning current approaches to these challenges.

T Cell Defects and Immunotherapy in Chronic Lymphocytic Leukemia

In the past few years, independent studies have highlighted the relevance of the tumor microenvironment (TME) in cancer, revealing a great variety of TME-related predictive markers, as well as identifying novel therapeutic targets in the TME. Cancer immunotherapy targets different components of the immune system and the TME at large in order to reinforce effector mechanisms or relieve inhibitory and suppressive signaling. Currently, it constitutes a clinically validated treatment for many cancers, including chronic lymphocytic leukemia (CLL), an incurable malignancy of mature B lymphocytes with great dependency on microenvironmental signals. Although immunotherapy represents a promising therapeutic option with encouraging results in CLL, the dysfunctional T cell compartment remains a major obstacle in such approaches. In the scope of this review, we outline the current immunotherapeutic treatment options in CLL in the light of recent immunogenetic and functional evidence of T cell impairment. We also highlight possible approaches for overcoming T cell defects and invigorating potent anti-tumor immune responses that would enhance the efficacy of immunotherapy.

A Rare Case of Synchronous Waldenström's Macroglobulinemia and Cutaneous Squamous Cell Carcinoma with a Lung Mass: A Diagnostic and Management Dilemma

Cutaneous squamous cell carcinoma has presented an increasing burden globally, with the occurrence of metastatic cutaneous squamous cell carcinoma being a relatively rare event but presenting with significant challenges in management, and a paucity of treatment options. Waldenström's macroglobulinemia is similarly an infrequent diagnosis. We present a rare case of a synchronous diagnosis of cutaneous squamous cell carcinoma and Waldenström's macroglobulinemia with an associated lung mass with squamous differentiation. The considered origin of the lung mass was either metastatic cutaneous squamous cell carcinoma or a primary squamous cell carcinoma of the lung, representing a third primary malignancy. The report highlights complexities in diagnosis and management, particularly in a patient with multiple synchronous malignancies. It further emphasizes the need for expanded global availability of specific therapies, including PD-1 inhibitors.

Targeted reduction of cholesterol uptake in cholesterol-addicted lymphoma cells blocks turnover of oxidized lipids to cause ferroptosis

Normal human cells can either synthesize cholesterol or take it up from lipoproteins to meet their metabolic requirements. In some malignant cells, de novo cholesterol synthesis genes are transcriptionally silent or mutated, meaning that cholesterol uptake from lipoproteins is required for survival. Recent data suggest that lymphoma cells dependent upon lipoprotein-mediated cholesterol uptake are also subject to ferroptosis, an oxygen- and iron-dependent cell death mechanism triggered by accumulation of oxidized lipids in cell membranes unless the lipid hydroperoxidase, glutathione peroxidase 4 (GPX4), reduces these toxic lipid species. To study mechanisms linking cholesterol uptake with ferroptosis and determine the potential role of the high-density lipoprotein (HDL) receptor as a target for cholesterol depleting therapy, we treated lymphoma cell lines known to be sensitive to the reduction of cholesterol uptake with HDL-like nanoparticles (HDL NPs). HDL NPs are a cholesterol-poor ligand that binds to the receptor for cholesterol-rich HDLs, scavenger receptor type B1 (SCARB1). Our data reveal that HDL NP treatment activates a compensatory metabolic response in treated cells toward increased de novo cholesterol synthesis, which is accompanied by nearly complete reduction in expression of GPX4. As a result, oxidized membrane lipids accumulate, leading to cell death through a mechanism consistent with ferroptosis. We obtained similar results in vivo after systemic administration of HDL NPs in mouse lymphoma xenografts and in primary samples obtained from patients with lymphoma. In summary, targeting SCARB1 with HDL NPs in cholesterol uptake-addicted lymphoma cells abolishes GPX4, resulting in cancer cell death by a mechanism consistent with ferroptosis.

Targeting CD205 with the antibody drug conjugate MEN1309/OBT076 is an active new therapeutic strategy in lymphoma models

Antibody drug conjugates represent an important class of anti-cancer drugs in both solid tumors and hematological cancers. Here, we report preclinical data on the anti-tumor activity of the first-in-class antibody drug conjugate MEN1309/OBT076 targeting CD205. The study included preclinical in vitro activity screening on a large panel of cell lines, both as single agent and in combination and validation experiments on in vivo models. CD205 was first shown frequently expressed in lymphomas, leukemias and multiple myeloma by immunohistochemistry on tissue microarrays. Anti-tumor activity of MEN1309/OBT076 as single agent was then shown across 42 B-cell lymphoma cell lines with a median IC50 of 200 pM and induction of apoptosis in 25/42 (59.5%) of the cases. The activity appeared highly correlated with its target expression. After in vivo validation as the single agent, the antibody drug conjugate synergized with the BCL2 inhibitor venetoclax, and the anti-CD20 monoclonal antibody rituximab. The first-in-class antibody drug targeting CD205, MEN1309/OBT076, demonstrated strong pre-clinical anti-tumor activity in lymphoma, warranting further investigations as a single agent and in combination.

Lessons Learned from Checkpoint Blockade Targeting PD-1 in Multiple Myeloma

Immune checkpoints and agonists modulate ongoing, antigen-specific immune responses. Therapeutic blockade of CTLA-4, PD-1, and PD-L1 has proven to be an effective treatment approach for a subset of patients with a variety of cancers of epithelial, mesenchymal, or hematologic origin. In multiple myeloma, a B-cell lymphoid malignancy of terminally differentiated plasma cells, PD-1 pathway blockade is ineffective as a single agent. The initial promise in combination approaches utilizing anti-PD-1 with the immunomodulatory drugs, lenalidomide or pomalidomide, was not confirmed in randomized trials. Here, we explore available data for and against manipulation of the PD-1 pathway and other immune checkpoints in myeloma and highlight several promising concepts and challenges that face ongoing development of immunotherapeutics for this disease.

Nectin-2 Expression on Malignant Plasma Cells Is Associated with Better Response to TIGIT Blockade in Multiple Myeloma

PURPOSE

T-cell immunoreceptor with Ig and ITIM domain (TIGIT) blockade could represent an alternative therapeutic option to release the immune response in patients with multiple myeloma. Here we analyzed the expression of TIGIT and its ligands poliovirus receptor (PVR) and nectin-2 in the bone marrow (BM) of patients with monoclonal gammopathies and the efficacy of TIGIT blockade activating antimyeloma immunity.

EXPERIMENTAL DESIGN

Expression levels of TIGIT and its ligands were characterized by flow cytometry and ELISA. TIGIT blockade was analyzed in in vitro functional assays with peripheral T cells. BM cells were studied with NanoString technology, real-time PCR, and ex vivo patient BM cell models.

RESULTS

TIGIT and its ligands are highly expressed in the BM of patients with multiple myeloma, suggesting that may play a role in restraining immune activation. TIGIT blockade depleted FoxP3⁺ Tregs while increasing proliferation of IFNγ-producing CD4⁺ T cells from patients with multiple myeloma. PVR ligation inhibited CD8⁺ T-cell signaling and cell proliferation which could be overcome with anti-TIGIT mAb. However, BM cells showed a remarkable heterogeneity in immune signature. Accordingly, functional ex vivo BM assays revealed that only some patients respond to checkpoint blockade. Thus, response to TIGIT blockade correlated with low frequency of TIGIT⁺ cells and high nectin-2 expression on malignant plasma cells.

CONCLUSIONS

TIGIT blockade efficiently reinvigorated peripheral T cells from patients with multiple myeloma. However, in the BM, the efficacy of blocking anti-TIGIT mAb to achieve tumor cell death may depend on the expression of TIGIT and nectin-2, becoming potential predictive biomarkers for identifying patients who may benefit from TIGIT blockade.

Identifying and treating candidates for checkpoint inhibitor therapies in multiple myeloma and lymphoma

Introduction: One of the hallmarks of cancerogenesis is the ability of tumor cells to evade the immune system. They can achieve it by abusing inhibitory immune checkpoint pathways, which, under normal circumstances, maintain peripheral tolerance during infection. Immune checkpoint inhibitors, especially anti-PD-1/PD-L1 monoclonal antibodies, currently represent a widely discussed treatment option not only in solid oncology, but in hematology-oncology as well.Areas covered: The manuscript is focused on clinical research concerning PD-1/PD-L1 blockade in lymphoma and multiple myeloma in order to identify the patients who would profit the most from this treatment modality. The authors reviewed articles on the topic on PubMed and relevant clinical trials on clinicaltrials.gov before October 2019.Expert opinion: So far, nivolumab and pembrolizumab have been approved for treating patients with relapsed/refractory classical Hodgkin lymphoma and primary mediastinal B cell lymphoma. Nevertheless, monotherapy alone is not curative and a combinational approach is needed. Modern treatment strategies and combinations are comprehensively summarized in this manuscript. There is no approved immune checkpoint inhibitor for the multiple myeloma indication. Although the combination of PD-1/PD-L1 inhibitors with immunomodulatory agents initially seemed promising, unexpected immune related toxicities have stopped any further development. Novel strategies and more potent combinations in myeloma and lymphoma are further discussed in the manuscript.

Identification of relapse-associated gene mutations by next-generation sequencing in low-risk acute myeloid leukaemia patients

Recommended genetic categorization of acute myeloid leukaemias (AML) includes a favourable-risk category, but not all these patients have good prognosis. Here, we used next-generation sequencing to evaluate the mutational profile of 166 low-risk AML patients: 30 core-binding factor (CBF)-AMLs, 33 nucleophosmin (NPM1)-AMLs, 4 biCEBPα-AMLs and 101 acute promyelocytic leukaemias (APLs). Functional categories of mutated genes differed among subgroups. NPM1-AMLs showed frequent variations in DNA-methylation genes (DNMT3A, TET2, IDH1/2) (79%), although without prognostic impact. Within this group, splicing-gene mutations were an independent factor for relapse-free (RFS) and overall survival (OS). In CBF-AML, poor independent factors for RFS and OS were mutations in RAS pathway and cohesin genes, respectively. In APL, the mutational profile differed according to the risk groups. High-risk APLs showed a high mutation rate in cell-signalling genes (P = 0·002), highlighting an increased incidence of FLT3 internal tandem duplication (ITD) (65%, P < 0·0001). Remarkably, in low-risk APLs (n = 28), NRAS mutations were strongly correlated with a shorter five-year RFS (25% vs. 100%, P < 0·0001). Overall, a high number of mutations (≥3) was the worst prognostic factor RFS (HR = 2·6, P = 0·003). These results suggest that gene mutations may identify conventional low-risk AML patients with poor prognosis and might be useful for better risk stratification and treatment decisions.

European interdisciplinary guideline on invasive squamous cell carcinoma of the skin: Part 2. Treatment

In order to update recommendations on treatment, supportive care, education and follow-up of patients with invasive cutaneous squamous cell carcinoma (cSCC), a multidisciplinary panel of experts from the European Dermatology Forum, the European Association of Dermato-Oncology and the European Organization of Research and Treatment of Cancer was formed. Recommendations were based on evidence-based literature review, guidelines and expert consensus. Treatment recommendations are presented for common primary cSCC (low risk, high risk), locally advanced cSCC, regional metastatic cSCC (operable or inoperable) and distant metastatic cSCC. For common primary cSCC (the most frequent cSCC type), first-line treatment is surgical excision with postoperative margin assessment or microscopically controlled sugery. Safety margins containing clinical normal-appearing tissue around the tumour during surgical excision and negative margins as reported in the pathology report are necessary to minimise the risk of local recurrence and metastasis. In case of positive margins, a re-excision shall be done, for operable cases. Lymph node dissection is recommended for cSCC with cytologically or histologically confirmed regional nodal involvement. Radiotherapy should be considered as curative treatment for inoperable cSCC, or for non-surgical candidates. Anti-PD-1 antibodies are the first-line systemic treatment for patients with metastatic or locally advanced cSCC who are not candidates for curative surgery or radiation, with cemiplimab being the first approved systemic agent for advanced cSCC by the Food and Drug Administration/European Medicines Agency. Second-line systemic treatments for advanced cSCC include epidermal growth factor receptor inhibitors (cetuximab) combined with chemotherapy or radiation therapy. Multidisciplinary board decisions are mandatory for all patients with advanced disease who require more than surgery. Patients should be engaged with informed decisions on management and be provided with best supportive care to optimise symptom management and improve quality of life. Frequency of follow-up visits and investigations for subsequent new cSCC depend on underlying risk characteristics.

Prognostic Value of Inducible Nitric Oxide Synthase (iNOS) in Human Cancer: A Systematic Review and Meta-Analysis

Background

Inducible nitric oxide synthase (iNOS) is confirmed to regulate the production of nitric oxide (NO) when cells are exposed to external stimulus. Recent publications revealed that overexpression of iNOS predicted poor clinical outcomes for patients with malignant cancers, e.g., gastric, bladder, and colorectal cancers; however, several studies reported no obvious relationship between iNOS expression and prognosis of solid tumors. The aim of our study was to investigate the pooled effect of the prognostic value of iNOS expression.

Materials and Methods

We performed a systematic search of PubMed, Web of Science, and Embase databases up to January 15, 2019. The concerned outcomes of interest included overall survival (OS), cancer-special survival (CSS), and recurrence-free survival (RFS).

Results

Fourteen studies with 1,758 patients were included in this meta-analysis, and we reached the conclusion that increased iNOS expression was significantly associated with worse OS (HR: 1.89, 95% CI: 1.57 - 2.28, p ≤ 0.001), worse CSS (HR: 3.13, 95% CI: 1.88 - 5.20, p ≤ 0.001), and worse RFS (HR: 2.16, 95% CI: 1.29 - 3.62, p = 0.003) in solid tumors. Furthermore, the subgroup analysis identified the significant relationship of high iNOS expression with poor OS in gastric cancer. No obvious publication bias was detected by Begg's tests.

Conclusion

In summary, the results drawn in our meta-analysis demonstrated that elevated expression of iNOS had a significant association with poor survival in human cancer. iNOS might serve as a promising predictive biomarker of prognosis in cancer patients, and well-designed prospective studies are further needed to substantiate the prognostic value of iNOS.

Second primary cancers in non-Hodgkin lymphoma: Family history and survival

Second primary cancers (SPCs) account for an increasing proportion of all cancer diagnoses and family history of cancer may be a risk factor for SPCs. Using the Swedish Family-Cancer Database on non-Hodgkin lymphoma (NHL), we assessed the influence of family history on risk of SPCs and of SPCs on survival. NHL patients were identified from the years 1958 to 2015 and generalized Poisson models were used to calculate relative risks (RRs) for SPCs and familial SPCs. Among 14,393 NHL patients, a total of 1,866 (13.0%) were diagnosed with SPC. Familial risk of nine particular cancers was associated with risks of these cancers as SPCs, with twofold to fivefold increase in RRs. At the end of a 25-year follow-up period, the survival probability for persons with SPC was only 20% of that for patients without SPC; the hazard ratio for SPC was 1.59 (95% CI: 1.46-1.72). Survival could be predicted by the prognostic groups based on first cancers and HRs increase systematically with worse prognosis yielding a trend of p = 4.6 × 10^-5 . SPCs had deleterious consequences for survival in NHL patients. Family history was associated with increasing numbers of SPCs. Prevention of SPCs and their early detection is an important target in the overall strategy to improve survival in NHL patients. Counseling for avoidance of risk factors and targeted screening based on family history are feasible steps in risk reduction.

Using Prognosis-Related Gene Expression Signature and Connectivity Map for Personalized Drug Repositioning in Multiple Myeloma

BACKGROUND Multiple myeloma (MM) is the second most common hematologic cancer with poor prognosis. Novel therapeutic strategies are needed to decrease the high mortality rate. The aim of this study was to identify prospective agents for MM. MATERIAL AND METHODS A microarray dataset was mined, which contains the transcriptome profiles of 588 MM patients. Univariate Cox analysis was performed to analyze the relationships between genes and clinical outcome. Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) were determined. Protective and risky genes were uploaded to Connectivity Map (CMAP) database to identify the potentially unknown effects of existing drugs. An example was selected to be docked on the known molecules. RESULTS A total of 1445 genes significantly correlated with the event free survival (EFS) of MM patients were identified and included 676 protective and 769 risky indicators. KEGG pathway analysis revealed that these prognosis-associated genes were enriched in the "cell cycle," "DNA replication," and "P53 signaling pathway". The top t3 most significant potential molecules were vorinostat, trifluoperazine, and thioridazine. CDK1 (cyclin-dependent kinase-1) ranked as the core in the class of prognosis-related genes in MM based on protein-protein interaction (PPI) network analysis. With Sybyl-X 2.0, the majority of the top 10 molecules aforementioned displayed high binding forces with CDK1. Among these molecules, trichostatin A had the greatest ability in combining with CDK1. CONCLUSIONS Genes that mainly accumulate in the cell cycle pathway play an essential role in the prognosis of MM, and these prognosis-related genes also have great value in drug development.

Clinical Development of PD-1 Blockade in Hematologic Malignancies

Clinical development of immune checkpoint inhibitors targeting the PD-1 pathway has led to clinical benefits for patients with multiple solid tumor and hematologic malignancies and has revolutionized modern oncology. High response rates to PD-1 blockade in patients with classical Hodgkin lymphoma and certain subtypes of non-Hodgkin lymphoma highlight an intrinsic biologic sensitivity to this strategy of treatment. Despite early success of checkpoint inhibitor and immunomodulatory drug combinations in phase 2 studies in multiple myeloma, safety concerns in patients treated with the combination of immunomodulatory drugs and checkpoint inhibitors in myeloma have stalled drug development in this space. Novel combination approaches exploring PD-1 inhibitors with epigenetic modifiers in leukemia are underway.

MGCD0103 induces apoptosis and simultaneously increases the expression of NF-κB and PD-L1 in classical Hodgkin's lymphoma

At present there is no consensus on the treatment of classical Hodgkin's lymphoma (CHL) following relapse. The aim of the present study was to access the class I-selective histone deacetylase (HDAC) inhibitor (HDACI) MGCD0103 on the expression levels of Bcl-2, nuclear factor (NF)-κB and programmed death-ligand 1 (PD-L1) in CHL, to explore the possible therapeutic value of MGCD0103 in combined relative target drugs for patients with CHL. In L1236 and L428 cell lines, apoptosis and cell cycle stage were identified using flow cytometry, and the effects of HDACI on CHL were assessed in terms of Bcl-2, NF-κB and PD-L1 expression levels, which were detected by western blotting and co-focusing experiments. The results demonstrated that MGCD0103 could induce cell apoptosis and cell cycle arrest, down-regulate Bcl-2 and increase NF-κB and PD-L1 expression levels in L1236 and L428 cell lines. MGCD0103 decreases Bcl-2 levels and upregulates PD-L1, which indicates that the combined use of HDACIs and a PD-L1 inhibitor in theory may improve treatment outcomes in patients with CHL. MGCD0103 may also up-regulate NF-κB, which seems to induce resistance towards anti-apoptotic drugs. Clinical trials combining HDACIs with NF-κB and/or PD-L1 inhibitors should be designed to further improve treatment outcomes for patients with CHL.

Osteoclast Immunosuppressive Effects in Multiple Myeloma: Role of Programmed Cell Death Ligand 1

Immunomodulatory drugs and monoclonal antibody-based immunotherapies have significantly improved the prognosis of the patients with multiple myeloma (MM) in the recent years. These new classes of reagents target malignant plasma cells (PCs) and further modulate the immune microenvironment, which prolongs anti-MM responses and may prevent tumor occurrence. Since MM remains an incurable cancer for most patients, there continues to be a need to identify new tumor target molecules and investigate alternative cellular approaches using gene therapeutic strategies and novel treatment mechanisms. Osteoclasts (OCs), as critical multi-nucleated large cells responsible for bone destruction in >80% MM patients, have become an attractive cellular target for the development of novel MM immunotherapies. In MM, OCs are induced and activated by malignant PCs in a reciprocal manner, leading to osteolytic bone disease commonly associated with this malignancy. Significantly, bidirectional interactions between OCs and MM cells create a positive feedback loop to promote MM cell progression, increase angiogenesis, and inhibit immune surveillance via both cell-cell contact and abnormal production of multiple cytokines/chemokines. Most recently, hyper-activated OCs have been associated with activation of programmed cell death protein 1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway, which impairs T cell proliferation and cytotoxicity against MM cells. Importantly, therapeutic anti-CD38 monoclonal antibodies and checkpoint inhibitors can alleviate OC-induced immune suppression. Furthermore, a proliferation-inducing ligand, abundantly secreted by OCs and OC precursors, significantly upregulates PD-L1 expression on MM cells, in addition to directly promoting MM cell proliferation and survival. Coupled with increased PD-L1 expression in other immune-suppressive cells, i.e., myeloid-derived suppressor cells and tumor-associated macrophages, these results strongly suggest that OCs contribute to the immunosuppressive MM BM microenvironment. Based on these findings and ongoing osteoimmunology studies, therapeutic interventions targeting OC number and function are under development to diminish both MM bone disease and related immune suppression. In this review, we discuss the classical and novel roles of OCs in the patho-immunology of MM. We also describe novel therapeutic strategies simultaneously targeting OCs and MM interactions, including PD-1/PD-L1 axis, to overcome the immune-suppressive microenvironment and improve patient outcome.

Extranodal NK/T-cell lymphoma: Updates in biology and management strategies

Extranodal NK/T-cell lymphoma, nasal type (ENKL), is a rare lymphoma subtype of peripheral T/NK-cell lymphoma that is very common in East Asia and Latin America. Two-thirds of patients have localized disease in the nasal cavity or adjacent sites. Large retrospective studies have revealed the clinicopathologic features of ENKL patients, identified risk factors for short survival time, and developed prognostic models. Next-generation sequencing studies have provided a comprehensive list of recurrent mutations in ENKL. Since the early 2000s, disease-specific therapeutic approaches have been developed, and the standard of care for ENKL has markedly changed. Non-anthracycline-containing chemotherapy with or without radiotherapy is the current standard approach for ENKL treatment. Emerging therapies, including the use of immune checkpoint inhibitors, are being investigated.