Novel targets for natural killer/T-cell lymphoma immunotherapy

CircADARB1 serves as a new biomarker in natural killer T-cell lymphoma and a potential regulator of p-Stat3

Background

Natural killer/T-cell lymphoma (NKTCL) is a rare and aggressive subtype of Non-Hodgkin’s Lymphoma. CircRNA has shown great potential to become a biomarker in plasma. In this study, we aimed to determine circRNA for its diagnostic and prognostic value and biological function in NKTCL.

Method

The circRNA microarray of plasma from NKTCL patients and healthy donors were conducted. The relative expressions of target circRNA were verified by qRT-PCR. We conducted function experiments in vitro and in vivo. Bioinformatics predicted the target miRNA of the target circRNA and the binding site was detected by the dual luciferase report assay. Downstream target protein was predicted and detected by western blot in vitro and immunohistochemistry in vivo.

Result

By analyzing the plasma circRNA microarrays in NKTCL, 6137 circRNAs were up-regulated and 6190 circRNAs were down-regulated. The relative expressions of circADARB1 were significantly higher in NKTCL patients. The knockdown of circADARB1 inhibited proliferation of NKTCL cells in vitro and in vivo. CircADARB1 could bind to miR-214-3p in the downstream and regulate the expression of p-Stat3. In nude mice tumor tissue, p-Stat3 was under-expressed in the circADARB1 knockdown group.

Conclusion

CircADARB1 was highly expressed in NKTCL plasma and circADARB1 was a potential biomarker to assist diagnosis and predict the response in NKTCL. CircADARB1 bound up to miR-214-3p and regulated p-Stat3.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02296-x.

Clinical efficacy of cisplatin, dexamethasone, gemcitabine and pegaspargase (DDGP) in the initial treatment of advanced stage (stage III-IV) extranodal NK/T-cell lymphoma, and its correlation with Epstein-Barr virus

Objective: To evaluate the clinical efficacy and safety of the DDGP regimen in treating extranodal NK/T-cell lymphoma and investigate the correlation between Epstein-Barr virus (EBV)-DNA variation after treatment and the clinical efficacy of NK/T-cell lymphoma.

Methods: Sixty-four patients with extranodal NK/T-cell lymphoma received DDGP regimen-based chemotherapy. Short-term and long-term clinical efficacy and adverse reactions were observed. The relationship between EBV-DNA changes before and after therapy and clinical efficacy was investigated.

Results: After the DDGP regimen was used as the initial treatment, the short-term clinical efficacy included 39 complete remission (CR) (60.94%), 12 partial remission (PR) (18.75%), 2 stable disease (SD) (3.13%) and 11 progressive disease (PD) (17.18%). Objective response rate (ORR) was 79.69% and 82.82% for disease control rate (DCR). 3-year progression-free survival (PFS) was 62.00% and 3-year overall survive (OS) was 74.90%. Hemocytopenia was the predominant adverse effect. Between EBV-DNA positive group and its negative counterpart, a significant difference was noted in OS (P=0.046), but no difference in ORR, DCR or PFS was observed. In the EBV-DNA positive group, ORR, DCR, PFS and OS were higher for patients whose EBV-DNA copy number decreased within a normal range than patients remained positive (93.33% versus 61.53%, P=0.041 for ORR; 93.33% versus 61.53%, P=0.041 for DCR, P=0.003 for PFS, P=0.017 for OS). The main adverse reactions included bone marrow suppression, gastrointestinal reaction and coagulation dysfunction, which were mitigated and treated after expectant or dose-decrement treatment.

Conclusion: DDGP regimen can significantly improve the clinical prognosis of NK/T-cell lymphoma patients with tolerable adverse reactions. The variation in EBV-DNA is correlated with clinical efficacy and prognosis, which provides a theoretical basis for NK/T-cell lymphoma therapy.

Clinical trial: In November 2011, this clinical trial was registered on the website: www.ClinicalTrials.gov (No. NCT01501149).

Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type: Basic Science and Clinical Progress

Extranodal natural killer (NK)/T-cell lymphoma, nasal type (NNKTL) has very unique epidemiological, etiologic, histologic, and clinical characteristics. It is commonly observed in Eastern Asia, but quite rare in the United States and Europe. The progressive necrotic lesions mainly in the nasal cavity, poor prognosis caused by rapid local progression with distant metastases, and angiocentric and polymorphous lymphoreticular infiltrates are the main clinical and histologic features. Phenotypic and genotypic studies revealed that the lymphoma is originated from either NK- or γδ T-cell, both of which express CD56. In 1990, the authors first reported the presence of Epstein-Barr virus (EBV)-DNA and EBV-oncogenic proteins, and EBV has now been recognized to play an etiological role in NNKTL. in vitro studies revealed that a wide variety of cytokines, chemokines, and micro RNAs, which may be produced by EBV-oncogenic proteins in the lymphoma cells, play important roles for tumor progression in NNKTL, and could be therapeutic targets. In addition, it was revealed that the interaction between NNKTL cells and immune cells such as monocytes and macrophages in NNKTL tissues contribute to lymphoma progression. For diagnosis, monitoring the clinical course and predicting prognosis, the measurements of EBV-DNAs and EBV-micro RNAs in sera are very useful. For treatment with early stage, novel concomitant chemoradiotherapy such as DeVIC regimen with local radiotherapy and MPVIC-P regimen using intra-arterial infusion developed with concomitant radiotherapy and the prognosis became noticeably better. However, the prognosis of patients with advanced stage was still poor. Establishment of novel treatments such as the usage of immune checkpoint inhibitor or peptide vaccine with molecular targeting therapy will be necessary. This review addresses recent advances in the molecular understanding of NNKTL to establish novel treatments, in addition to the epidemiologic, clinical, pathological, and EBV features.

Conserved cell populations in doxorubicin-resistant human nasal natural killer/T cell lymphoma cell line: super multidrug resistant cells?

Background

Extranodal NK/T-cell lymphoma, nasal type (ENKL) is a distinct clinicopathological entity and EBV-associated disease that is highly aggressive. Many patients had failed to respond to conventional chemotherapy or relapsed after treatment. Multi-drug resistance is a major cause that leads to these desperate failures. However, the specific mechanism of drug resistance is still unclear.

Methods

In the previous study, we firstly developed a doxorubicin-resistant ENKL cell line known as SNK-6/ADM, and then a small quantity of side population (SP) cells were derived from SNK-6/ADM and named SNK-6/ADM-SP. In order to explore the biological characteristics and mechanism of drug-resistance of these cells, SNK-6, SNK-6/ADM and SNK-6/ADM-SP cells were utilized to evaluate potentially differences of chemotherapy resistance index (RI), morphology, proliferation, cell cycles, expression of ATP-binding cassette (ABC) transporters (ABCG1, ABCG2 and ABCC4) and surface markers, cytokine sensitivity, and situation of EBV infection.

Results

We identified SNK-6/ADM-SP is a specific multidrug resistant cell population with a higher level of RI than SNK-6/ADM. Relevant evaluations showed that SNK-6/ADM-SP presented a series of conserved biological behaviors including relatively poor proliferation ability, high expression of ABCG2, weak sensitivity to IL-15 which could stimulate normal ENKL cells’ proliferation and differentiation, and EBV inhibition with low level of EBV-DNA replication and EBV-antigen expression.

Conclusions

This discovered cellular heterogeneity of ENKL could provide a new perspective to better understand the mechanisms of drug resistance and overcome elusive response to chemotherapy of ENKL.

Successful treatment with anti-programmed-death-1 antibody in a relapsed natural killer/T-cell lymphoma patient with multi-line resistance: a case report

Background

Extranodal natural killer/T-cell lymphoma (NKTCL), nasal type, is an aggressive malignancy with poor prognosis. Currently, there is no recommended standard therapy for relapsed NKTCL.

Case presentation

A 37-year-old woman with lymphadenopathy was diagnosed with NKTCL by biopsy of an enlarged lymph node on the right side of her neck. Enhanced computed tomography revealed no metastasis. For this patient, we performed continuous chemotherapy followed by radiotherapy; however, nodule biopsy showed metastases in her lower limbs 3 months after radiotherapy, which confirmed disease progression. Unfortunately, the patient^’ s temperature was persistently high and her skin ulcers could not be controlled well using multi-line treatment. Therefore, we attempted treatment with the anti-programmed-death-1 (PD-1) antibody, pembrolizumab. Surprisingly, the patient achieved clinical complete remission (CR) after four cycles of pembrolizumab treatment, despite having persistent detectable Epstein-Barr virus (EBV) DNA. Other molecular monitoring techniques were unavailable for this patient owing to the retrospective nature of the study. The only adverse event was soreness of the upper limb joints and muscles.

Conclusion

This relapsed NKTCL case treated with pembrolizumab showed that multimodal therapy including pembrolizumab would be partially or totally effective for relapsed NKTCL.