Clinical significance of serum soluble interleukin-2 receptor-α in extranodal natural killer/T-cell lymphoma (ENKTL): a predictive biomarker for treatment efficacy and valuable prognostic factor

Sintilimab (anti-PD-1 antibody) plus chidamide (histone deacetylase inhibitor) in relapsed or refractory extranodal natural killer T-cell lymphoma (SCENT): a phase Ib/II study

Anti-PD-1 antibodies are a favorable treatment for relapsed or refractory extranodal natural killer T cell lymphoma (RR-ENKTL), however, the complete response (CR) rate and the duration of response (DOR) need to be improved. This phase 1b/2 study investigated the safety and efficacy of sintilimab, a fully human anti-PD-1 antibody, plus chidamide, an oral subtype-selective histone deacetylase inhibitor in 38 patients with RR-ENKTL. Expected objective response rate (ORR) of combination treatment was 80%. Patients received escalating doses of chidamide, administered concomitantly with fixed-dose sintilimab in 21-days cycles up to 12 months. No dose-limiting events were observed, RP2D of chidamide was 30 mg twice a week. Twenty-nine patients were enrolled in phase 2. In the intention-to-treat population (n = 37), overall response rate was 59.5% with a complete remission rate of 48.6%. The median DOR, progression-free survival (PFS), and overall survival (OS) were 25.3, 23.2, and 32.9 months, respectively. The most common grade 3 or higher treatment-emergent adverse events (AEs) were neutropenia (28.9%) and thrombocytopenia (10.5%), immune-related AEs were reported in 18 (47.3%) patients. Exploratory biomarker assessment suggested that a combination of dynamic plasma ctDNA and EBV-DNA played a vital prognostic role. STAT3 mutation shows an unfavorable prognosis. Although outcome of anticipate ORR was not achieved, sintilimab plus chidamide was shown to have a manageable safety profile and yielded encouraging CR rate and DOR in RR-ENKTL for the first time. It is a promising therapeutic option for this population.

Advances and challenges of immunotherapies in NK/T cell lymphomas

Natural killer (NK)/T cell lymphoma (NKTCL) is a rare subtype of Epstein-Barr virus (EBV)-associated non-Hodgkin lymphoma characterized by poor clinical outcomes. It is more common in East Asian and Latin American countries. Despite the introduction of asparaginase/pegaspargase-based chemotherapy, the prognosis of patients with advanced NKTCL needs to be improved, and few salvage treatment options are available for relapsed/refractory patients who fail chemotherapy. Although many unknowns remain, novel treatment strategies to further improve outcomes are urgently needed. Immunotherapy has emerged and shown favorable antitumor activity in NKTCL, including monoclonal antibodies targeting immune checkpoint inhibitors, other receptors on the cellular membrane, and cellular immunotherapy, which could enhance immune cells attack on tumor cells. In this review, we provide an overview of recent immunotherapy in NKTCL, focusing on programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1), cytotoxic T lymphocyte-associated protein 4 (CTLA-4), chimeric antigen receptor (CAR) T cells, EBV-specific cytotoxic T lymphocytes, immunomodulatory agents, and other targeted agents, as well as the current progress and challenges in the field.

Exposure-response analysis of Camidanlumab tesirine in patients with relapsed or refractory classical Hodgkin lymphoma and non-Hodgkin lymphoma

PURPOSE

To investigate camidanlumab tesirine (Cami) exposure-response (E-R) relationships, using an integrated population pharmacokinetic model, for patients with classical Hodgkin lymphoma (cHL) and non-Hodgkin lymphoma enrolled in an open-label, phase 1 study (NCT02432235).

METHODS

Exploratory analyses investigated relationships between exposure measures (C_maxss, C_minss, and C_avgss) and the occurrence of binary variables (overall response rate [ORR] and selected adverse events [AEs]) and nonbinary variables (overall survival [OS]).

RESULTS

Exploratory analyses showed a significant, positive relationship between exposure and ORR/OS. The final model showed this effect was non-significant due to the covariate effects. Cami exposures were higher in patients with selected grade ≥ 2 AEs at cycle 6 (the anticipated steady-state exposure level), confirmed in the final E-R models.

CONCLUSIONS

Based on univariate results, C_maxss was used as the exposure measure in all models, except for the autoimmune AE full E-R model in which C_avgss was used. The positive relationship between exposure and ORR/OS (higher exposure significantly associated with higher probabilities of ORR/OS) was not statistically significant in the final models. The final safety E-R models demonstrated a significant positive association between Cami exposure and selected grade ≥ 2 AEs, with higher exposures associated with higher probabilities of experiencing the grade ≥ 2 AEs at cycle 6. The results identify preliminary predictors of efficacy and safety and provide a basis for a dosing rationale and benefit-risk profile of Cami in patients with relapsed/refractory cHL.

Towards Next Generation Biomarkers in Natural Killer/T-Cell Lymphoma

Natural killer/T-cell lymphoma (NKTCL) is an Epstein-Barr virus-associated non-Hodgkin lymphoma linked to an aggressive clinical course and poor prognosis. Despite an improvement in survival outcomes with the incorporation of novel agents including immune checkpoint inhibitors in the treatment of NKTCL, a significant proportion of patients still relapse or remain refractory to treatment. Several clinical prognostic models have been developed for NKTCL patients treated in the modern era, though the optimal approach to risk stratification remains to be determined. Novel molecular biomarkers derived from multi-omic profiling have recently been developed, with the potential to improve diagnosis, prognostication and treatment of this disease. Notably, a number of potential biomarkers have emerged from a better understanding of the tumor immune microenvironment and inflammatory responses. This includes a recently described 3'UTR structural variant in the PD-L1 gene, which confers susceptibility to checkpoint immunotherapy. In this review, we summarize the biomarker landscape of NKTCL and highlight emerging biomarkers with the potential for clinical implementation.

The landscape of new drugs in extranodal NK/T-cell lymphoma

To date, much progress has been made in early-stage extranodal NK/T-cell lymphoma (ENKTCL), and risk-adapted therapy with radiotherapy (RT) alone for the low-risk group and RT combined with asparaginase-based chemotherapy (CT) for the high-risk group yields favorable outcomes. However, optimal treatment strategies have not been defined yet for advanced-stage ENKTCL. Historically, ENKTCL responded poorly to conventional anthracycline-based chemotherapy probably because of inherent multidrug resistance (MDR). The fact that ENKTCL cells lack asparagine synthetase (ASNS) activity warranted the use of L-asparaginase or pegaspargase as frontline chemotherapies. Even though, due to high mortality of the disease, approximately 50% patients failing the frontline therapy arrived at dismal clinical outcomes with a median progression-free survival (PFS) less than 8 months. As distinctive molecular and biological subgroups are increasingly discovered within the disease entity of ENKTCL, novel targeted therapies and immunotherapy are of the urgent need for those heterogeneous subgroups. In this review, we sought to summarize the preclinical and clinical results of 6 categories of promising targeted therapy and immunotherapy for the treatment of ENKTCL, including monoclonal antibodies, immune checkpoint inhibitors, small-molecular inhibitors, epigenetic therapy, immunomodulatory drugs, and adoptive T-cell therapy, and these might change the landscape of treatment for ENKTCL in the near future.

Prognostic nomogram incorporating inflammatory cytokines for overall survival in patients with aggressive non-Hodgkin's lymphoma

BACKGROUND

This study aimed to investigate the association of pre-treatment inflammatory status with survival time and to develop a prognostic nomogram incorporating inflammatory cytokines in non-Hodgkin's lymphoma.

METHODS

A total of 228 patients with diffuse large B-cell lymphoma (DLBCL) received R-CHOP-based regimens from a prospective randomized study (NCT01852435) were included as a training cohort. Other cohorts of 886 lymphoma patients were served as validation cohorts. Lymphocyte-monocyte ratio (LMR), serum levels of soluble interleukin s(IL)-2R, IL-6, IL-8, IL-10 and tumor necrosis factor-α (TNF-α), were assessed before treatment. Least absolute shrinkage and selection operator (LASSO) regression were used to select variables for nomogram of overall survival (OS). The predictive accuracy of the nomogram was determined by concordance index (C-index).

FINDINGS

The nomogram included lactate dehydrogenase (LDH), sIL-2R, TNF-α and decreased LMR. The C-index of the nomogram for OS prediction were range from 0.61 to 0.86 for training cohort of DLBCL and validation cohorts of DLBCL, PTCL, NKTCL and ASCT, which were superior to the predictive power of International Prognostic Index (IPI, 0.67 to 0.84) or NCCN-IPI (0.59 to 0.78), but not in those of indolent lymphoma like FL and MALT.

INTERPRETATIONS

The nomogram incorporating inflammatory cytokines provides a useful tool for risk stratification in aggressive non-Hodgkin's lymphomas. FUND: National Natural Science Foundation of China, the Shanghai Commission of Science and Technology, Multicenter Clinical Research Project by Shanghai Jiao Tong University School of Medicine, Clinical Research Plan of SHDC, and Chang Jiang Scholars Program.

IL-2Rα up-regulation is mediated by latent membrane protein 1 and promotes lymphomagenesis and chemotherapy resistance in natural killer/T-cell lymphoma

BACKGROUND

Natural killer/T-cell lymphoma (NKTCL) is a highly aggressive non-Hodgkin lymphoma often resistant to chemotherapy. Serum level of soluble IL-2 receptor α (IL-2Rα) is elevated in NKTCL patients and correlates significantly with treatment response and survival. In the current study we examined the potential role of IL-2Rα by over-expressing IL-2Rα in representative cell lines.

METHODS

Levels of IL-2Rα were evaluated in the human natural killer cell line NK-92 and the NKTCL cell line SNK-6. Lentiviral vectors were used to express latent membrane protein 1 (LMP1) in NK-92 cells, and IL-2Rα in both NK-92 and SNK-6 cells. The biological effects of these genes on proliferation, apoptosis, cell cycle distribution, and chemosensitivity were analyzed.

RESULTS

Expression of IL-2Rα was significantly higher in SNK-6 cells than in NK-92 cells. Expressing LMP1 in NK-92 cells remarkably up-regulated IL-2Rα levels, whereas selective inhibitorss of the proteins in the MAPK/NF-κB pathway significantly down-regulated IL-2Rα. IL-2Rα overexpression in SNK-6 cells promoted cell proliferation by altering cell cycle distribution, and induced resistance to gemcitabine, doxorubicin, and asparaginase. These effects were reversed by an anti-IL-2Rα antibody.

CONCLUSIONS

Our results suggest that LMP1 activates the MAPK/NF-κB pathway in NKTCL cells, up-regulating IL-2Rα expression. IL-2Rα overexpression promotes growth and chemoresistance in NKTCL, making this interleukin receptor a potential therapeutic target.

Inhibiting IL-2 signaling and the regulatory T-cell pathway using computationally designed peptides

Background Increased serum levels of soluble interleukin-2 (IL-2) receptor alpha (sIL-2Rα) are an indicator of poor prognosis in patients with B-cell non-Hodgkin lymphoma (NHL). By binding to IL-2, sIL-2Rα upregulates Foxp3 expression and induces the development of regulatory T (T_reg) cells. Methods To inhibit the binding of IL-2 to sIL-2Rα with the goal of suppressing the induction of Foxp3 and decreasing T_reg cell numbers, we developed peptides by structure-based computational design to disrupt the interaction between IL-2 and sIL-2Rα. Each peptide was screened using an enzyme-linked immunosorbent assay (ELISA), and 10 of 22 peptides showed variable capacity to inhibit IL-2/sIL-2Rα binding. Results We identified a lead candidate peptide, CMD178, which consistently reduced the expression of Foxp3 and STAT5 induced by IL-2/sIL-2Rα signaling. Furthermore, production of cytokines (IL-2/interferon gamma [IFN-γ]) and granules (perforin/granzyme B) was preserved in CD8⁺ T cells co-cultured with IL-2-stimulated CD4⁺ T cells that had been pretreated with CMD178 compared to CD8⁺ cells co-cultured with untreated IL-2-stimulated CD4⁺ T cells where it was inhibited. Conclusions We conclude that structure-based peptide design can be used to identify novel peptide inhibitors that block IL-2/sIL-2Rα signaling and inhibit T_reg cell development. We anticipate that these peptides will have therapeutic potential in B-cell NHL and other malignancies.

Useful laboratory markers for the diagnosis of bone marrow involvement by malignant lymphoma

INTRODUCTION

This study aimed to investigate the effect of bone marrow involvement by malignant lymphoma (BMI) on laboratory data and to determine the useful laboratory markers for diagnosing BMI.

METHODS

We compared laboratory data between patients with and without BMI. We performed multivariate logistic regression and receiver operating characteristic (ROC) analyses to evaluate the diagnostic values of independent predictors.

RESULTS

In the BMI group, platelets in peripheral blood (PLT) and megakaryocyte count in bone marrow (MgK) were significantly lower than those in the non-BMI group (PLT, P < .0001; MgK, P = .0384). The rate of peripheral blood involvement by malignant lymphoma (PBI), red blood cell distribution width (RDW), D-dimer (DD), soluble interleukin-2 receptor (sIL2R), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) was significantly higher in the BMI group than in the non-BMI group (PBI, P < .0001; RDW, P = .0190; DD, P = .0006; sIL2R, P < .0001; AST, P = .0256; LDH, P = .0002). In multivariate analysis, PBI, PLT, sIL2R, and MgK levels were independent predictors of BMI.

CONCLUSION

PBI, PLT, sIL2R, and MgK may be the useful laboratory markers for BMI diagnosis.

Post-treatment plasma EBV-DNA positivity predicts early relapse and poor prognosis for patients with extranodal NK/T cell lymphoma in the era of asparaginase

Circulating Epstein-Barr virus (EBV) DNA is a biomarker of EBV-associated malignancies. Its prognostic value in early stage NK/T-cell lymphoma (NKTCL) in the era of asparaginase was investigated. 68 patients were treated with a median of 4 cycles of asparaginase-based chemotherapy followed by a median of 54.6Gy (range 50–60Gy) radiation. The amount of EBV-DNA was prospectively measured in both pretreatment and post-treatment plasma samples by real-time quantitative PCR. At the end of treatment, complete response (CR) rate was 79.4%, and overall response rate (ORR) was 88.2%. Patients with negative pretreatment EBV-DNA had a higher CR rate (96.0% vs. 69.8%, p = 0.023). The 3-year progression-free survival (PFS) rate and overall survival (OS) rate was 71% and 83%, respectively. In multivariate survival analysis, post-treatment EBV-DNA positivity and treatment response (non-CR) were prognostic factors for both worse PFS and OS (p < 0.05). Local tumor invasion was also a prognostic factor for worse OS (p = 0.010). In patients with CR, post-treatment EBV-DNA positivity correlated with inferior PFS and OS (both p < 0.0001). In patients with positive pretreatment EBV-DNA, negative post-treatment EBV-DNA correlated with better PFS and OS (both p < 0.0001). These findings indicate that post-treatment EBV-DNA positivity can predict early relapse and poor prognosis for patients with early stage NKTCL in the era of asparaginase, and may be used as an indicator of minimal residual disease.

High Pretreatment D-Dimer Levels Correlate with Adverse Clinical Features and Predict Poor Survival in Patients with Natural Killer/T-Cell Lymphoma

Pretreatment plasma D-dimer levels have been reported to predict survival in several types of malignancies. The aim of this study was to evaluate the prognostic value of D-dimer levels in patients with newly diagnosed natural killer/T-cell lymphoma (NKTCL). The cut-off value of D-dimer to predict survival was set as 1.2 μg/mL based on the receiver operating curve analysis. Patients with a D-dimer level ≥ 1.2 μg/mL had significantly more adverse clinical features, including poor performance status, advanced stage diseases, B symptoms, elevated serum lactic dehydrogenase levels, involvement of regional lymph nodes, more extranodal diseases, and higher International Prognostic Index and natural killer/T-cell lymphoma prognostic index scores. A D-dimer level ≥ 1.2 μg/mL was significantly associated with inferior 3-year overall survival (OS, 13.0 vs. 68.5%, P < 0.001). In the multivariate analysis, a D-dimer level ≥ 1.2 μg/mL remained an independent predictor for worse OS (HR: 3.13, 95% CI: 1.47-6.68, P = 0.003) after adjusting for other confounding prognostic factors. Among patients with Ann Arbor stage I-II diseases, those with a D-dimer level ≥ 1.2 μg/mL had a significantly worse survival than those with a D-dimer level < 1.2 μg/mL (3 year-OS: 76.2 vs. 22.2%, P < 0.001). Survival of early-stage patients with a high D-dimer level was similar to that of the advanced-stage patients. In conclusion, pretreatment plasma D-dimer level may serve as a simple but effective predictor of prognosis in patients with NKTCL.

Increased serum levels of interleukin-10 predict poor prognosis in extranodal natural killer/T-cell lymphoma patients receiving asparaginase-based chemotherapy

There are currently no prognostic biomarkers for extranodal natural killer/T-cell lymphoma (ENKTL) patients receiving asparaginase-based chemotherapy. Interleukin-10 (IL-10) is a pleiotropic cytokine that is involved in the stimulation and suppression of immune responses and influences the prognosis of different subtypes of lymphoma. We retrospectively analyzed 98 newly diagnosed patients with ENKTL receiving asparaginase-based chemotherapy. Baseline serum IL-10 levels were tested with sandwich enzyme-linked immunosorbent assays. Patients with high IL-10 (≥12.28 pg/mL) at diagnosis tended to have more adverse clinical features. Patients with low IL-10 (<12.28 pg/mL) at diagnosis had better progression-free survival (PFS) (P>0.001) and overall survival (OS) (P<0.001). Multivariate analysis revealed that baseline serum IL-10 level ≥12.28 pg/mL, stage III/IV, elevated serum ferritin, and elevated serum Epstein-Barr virus DNA level at diagnosis were four adverse factors for PFS and OS. Based on these four independent prediction factors, we divided the patients into different subgroups as follows: group 1, no adverse factors; group 2, one factor; group 3, two factors; and group 4, three or four factors. Furthermore, significant differences in PFS and OS were found between the groups. Our results suggest that pretreatment serum IL-10 is a novel, powerful predictor of prognosis for ENKTL patients receiving asparaginase-based chemotherapy, which suggests a role for IL-10 in the pathogenesis of this disease and offers new insight into potential therapeutic strategies.

Histopathological and immunophenotypical criteria for the diagnosis of Sézary syndrome in differentiation from other erythrodermic skin diseases: a European Organisation for Research and Treatment of Cancer (EORTC) Cutaneous Lymphoma Task Force Study of 97 cases

BACKGROUND

Patients with erythrodermic disease are a diagnostic challenge regarding the clinical and histological differential diagnosis.

OBJECTIVES

To evaluate histopathological and immunohistochemical diagnostic markers for Sézary syndrome.

METHODS

Ninety-seven erythrodermic cases [Sézary syndrome (SS), n = 57; erythrodermic inflammatory dermatoses (EIDs), n = 40] were collected by the EORTC Cutaneous Lymphoma Task Force histopathology group. Evaluation criteria were (i) epidermal and dermal changes; (ii) morphology of the infiltrate; (iii) immunohistochemical analysis of marker loss (CD2, CD3, CD4, CD5 and CD7); (iv) bystander infiltrate by staining for CD8, FOXP3 and CD25; and (v) expression of Ki-67, CD30, PD-1 and MUM-1.

RESULTS

The workshop panel made a correct diagnosis of SS in 51% of cases (cutaneous T-cell lymphoma 81%) and of EID in 80% without clinical or laboratory data. Histology revealed a significantly increased degree of epidermotropism (P < 0.001) and more intraepidermal atypical lymphocytes (P = 0.0014) in SS biopsies compared with EID. Pautrier microabscesses were seen only in SS (23%) and not in EID (P = 0.0012). SS showed significantly more dermal cerebriform and blastic lymphocytes than EID. Immunohistochemistry revealed a significant loss of CD7 expression (< 50%) in 33 of 51 (65%) cases of SS compared with two of 35 (6%) EID (P < 0.001). The lymphocytic infiltrate in SS skin samples was found significantly to express PD-1 (P = 0.0053), MUM-1 (P = 0.0017) and Ki-67 (P < 0.001), and showed less infiltration of CD8(+) lymphocytes (P < 0.001). A multivariate analysis identified CD7 loss, increased numbers of small cerebriform lymphocytes, low numbers of CD8(+) lymphocytes and increased proliferation (Ki-67(+) lymphocytes) as the strongest indicators for the diagnosis of SS.

CONCLUSIONS

A number of different histological and immunophenotypical criteria are required to differentiate between SS and EIDs.

Management of advanced NK/T-cell lymphoma

NK/T-cell lymphomas are aggressive malignancies, and the outlook is poor when conventional anthracycline-containing regimens designed for B-cell lymphomas are used. With the advent of L-asparaginase-containing regimens, treatment outcome has significantly improved. L-asparaginase-containing regimens are now considered the standard in the management of NK/T-cell lymphomas. In advanced diseases, however, outcome remains unsatisfactory, with durable remission achieved in only about 50% of cases. Stratification of patients with advanced NK/T-cell lymphomas is needed, so that poor-risk patients can be given additional therapy to improve outcome. Conventional presentation parameters are untested and appear inadequate for prognostication when L-asparaginase-containing regimens are used. Recent evidence suggests that dynamic factors during treatment and interim assessment, including Epstein-Barr virus (EBV) DNA quantification and positron emission tomography computed tomography findings, are more useful in patient stratification. The role of high-dose chemotherapy and haematopoietic stem cell transplantation requires evaluation in an overall risk-adapted treatment algorithm.

A modified international prognostic index including pretreatment hemoglobin level for early stage extranodal natural killer/T cell lymphoma

In this study, we investigated the prognostic role of pretreatment hemoglobin level in 321 patients with stage I/II extranodal natural killer (NK/T cell lymphoma (ENKTL). Patients with pretreatment hemoglobin level < 120 g/L had significantly inferior progression-free survival (PFS) and overall survival (OS) than those with hemoglobin level ≥ 120 g/L (p < 0.05). In a multivariate Cox regression model, age, Eastern Cooperative Oncology Group (performance status), lactate dehydrogenase level, Ann Arbor stage and pretreatment hemoglobin level were all independent prognostic factors for PFS and OS (p < 0.05). Using these five parameters, a modified international prognostic index (mIPI) model was constructed. This mIPI could categorize three groups with significantly different PFS and OS (both p < 0.0001) in both the training set and the validation set. In conclusion, this study confirmed the prognostic role of pretreatment hemoglobin level in ENKTL, and a newly modified IPI including pretreatment hemoglobin level could be used to further optimize treatments for patients with stage I/II ENKTL, especially in the era of asparaginase.

Lymphopenia during routine follow-up may predict relapse in patients with extranodal NK/T cell lymphoma

Recently, absolute lymphocyte count (ALC) at diagnosis, as a surrogate marker of host immunity, has been reported to be a prognostic factor for clinical outcomes in extranodal NK/T cell lymphoma (ENKTL). In this retrospective study, we set out to investigate whether ALC at the time of confirmed relapse or at last follow-up is a marker for relapse after chemoradiotherapy in 84 patients with stage I/II ENKTL. Receiver operating characteristics (ROC) curve and area under the curve (AUC) analysis showed that ALC at follow-up was a significant marker for relapse (AUC = 0.883, P < 0.001). Using 1.215 × 10(9)/L as the optimal cutoff value of ALC, 44 patients (52.4%) were in lower ALC group and 40 patients (47.6%) were in higher ALC group. The sensitivity and specificity for ALC at the time of confirmed relapse or at last follow-up was 94.1 and 76.0%, respectively. The relative risk of relapse with an ALC < 1.215 × 10(9)/L was 14.5. The positive predictive value with an ALC < 1.215 × 10(9)/L was 72.7%, and the negative predictive value with an ALC ≥ 1.215 × 10(9)/L was 95.0%. The 4-year cumulative incidence rate for an ALC < 1.215 × 10(9)/L was 73.2% compared with 3.2% for an ALC ≥ 1.215 × 10(9)/L (P < 0.001). In a multivariate regression analysis, ALC at the time of confirmed relapse or last follow-up remained to be a significant factor for relapse (P < 0.001). In conclusion, lymphopenia observed during routine follow-up can predict relapse in patients with ENKTL, which needs further validation in prospective trials.