Summary
Peripheral T‐cell lymphomas (PTCL) and natural killer (NK)/T‐cell lymphomas (NKTCL) are a heterogeneous group of aggressive malignancies with dismal outcomes and limited treatment options. ...While the phosphatidylinositol 3‐kinase (PIK3) pathway has been shown to be highly activated in many B‐cell lymphomas, its therapeutic relevance in PTCL and NKTCL remains unclear. The aim of this study is to investigate the expression of PIK3 and phosphatase and tensin homolog (PTEN) in these subtypes of lymphoma and to identify potential therapeutic targets for clinical testing. Therefore, the expression of PIK3α, PIK3β, PIK3γ, PIK3δ and PTEN was analyzed in 88 cases of PTCL and NKTCL samples by immunohistochemistry. All PTCL and NKTCL samples demonstrated high expression of PIK3 isoforms. In particular, high PIK3α expression was significantly associated with poor survival, even after adjustment for age, International Prognostic Index (IPI) score and anthracycline‐based chemotherapy in first line. Notably, copanlisib, a pan‐class I inhibitor with predominant activities towards PIK3α and PIK3δ isoforms, effectively inhibited phosphorylation of AKT, 4E‐BP‐1 and STAT3, causing G0/G1 cell cycle arrest and resulting in suppression of tumour cell growth in vitro and in vivo. This study provides evidence that targeting the PIK3 pathway, particularly simultaneous inhibition of PIK3α and δ, could be a promising approach for the treatment of PTCL and NKTCL.
Extranodal NK/T-cell lymphoma, nasal type (NKTL) is an aggressive type of non-Hodgkin lymphoma closely associated with Epstein-Barr virus and characterized by varying degrees of systemic ...inflammation. We aim to examine the prognostic significance of peripheral blood neutrophil-lymphocyte ratio (NLR) in patients with NKTL. Therefore, we conducted a retrospective review of 178 patients with biopsy-proven NKTL from the National Cancer Centre Singapore and Samsung Medical Center, South Korea. Using receiver operating curve analysis, an optimal cut-off for high NLR (>3.5) in predicting overall survival (OS) was derived. Survival analysis was performed using the Kaplan-Meier method and multivariable Cox proportional regression. In patients with high NLR, estimated 5-year OS was 25% compared to 53% in those with low NLR. In multivariable analysis, high NLR, in addition to age ≥60 years, presence of B-symptoms and stage III/IV at diagnosis, was independently correlated with worse OS (HR 2.08; 95% CI 1.36 to 3.18; p = 0.0008) and progression-free survival (HR 1.66; 95% CI 1.11 to 2.46; p = 0.0128). A new prognostic index (NABS score) derived from these factors stratified patients into low (0), low-intermediate (1), high-intermediate (2) and high (3-4) risk subgroups, which were associated with 5-year OS of 76.5%, 55.7%, 29.2% and 0% respectively. In conclusion, high NLR is an independent prognostic marker and the NABS model can be used to risk-stratify NKTL patients.
With lowering costs of sequencing and genetic profiling techniques, genetic drivers can now be detected readily in tumors but current prognostic models for Natural‐killer/T cell lymphoma (NKTCL) have ...yet to fully leverage on them for prognosticating patients. Here, we used next‐generation sequencing to sequence 260 NKTCL tumors, and trained a genomic prognostic model (GPM) with the genomic mutations and survival data from this retrospective cohort of patients using LASSO Cox regression. The GPM is defined by the mutational status of 13 prognostic genes and is weakly correlated with the risk‐features in International Prognostic Index (IPI), Prognostic Index for Natural‐Killer cell lymphoma (PINK), and PINK‐Epstein–Barr virus (PINK‐E). Cox‐proportional hazard multivariate regression also showed that the new GPM is independent and significant for both progression‐free survival (PFS, HR: 3.73, 95% CI 2.07–6.73; p < .001) and overall survival (OS, HR: 5.23, 95% CI 2.57–10.65; p = .001) with known risk‐features of these indices. When we assign an additional risk‐score to samples, which are mutant for the GPM, the Harrell's C‐indices of GPM‐augmented IPI, PINK, and PINK‐E improved significantly (p < .001, χ2 test) for both PFS and OS. Thus, we report on how genomic mutational information could steer toward better prognostication of NKTCL patients.
Extranodal natural killer T-cell lymphoma (NKTCL; nasal type) is an aggressive malignancy with a particularly high prevalence in Asian and Latin American populations. Epstein-Barr virus infection has ...a role in the pathogenesis of NKTCL, and HLA-DPB1 variants are risk factors for the disease. We aimed to identify additional novel genetic variants affecting risk of NKTCL.
We did a genome-wide association study of NKTCL in multiple populations from east Asia. We recruited a discovery cohort of 700 cases with NKTCL and 7752 controls without NKTCL of Han Chinese ancestry from 19 centres in southern, central, and northern regions of China, and four independent replication samples including 717 cases and 12 650 controls. Three of these independent samples (451 cases and 5301 controls) were from eight centres in the same regions of southern, central, and northern China, and the fourth (266 cases and 7349 controls) was from 11 centres in Hong Kong, Taiwan, Singapore, and South Korea. All cases had primary NKTCL that was confirmed histopathologically, and matching with controls was based on geographical region and self-reported ancestry. Logistic regression analysis was done independently by geographical regions, followed by fixed-effect meta-analyses, to identify susceptibility loci. Bioinformatic approaches, including expression quantitative trait loci, binding motif and transcriptome analyses, and biological experiments were done to fine-map and explore the functional relevance of genome-wide association loci to the development of NKTCL.
Genetic data were gathered between Jan 1, 2008, and Jan 23, 2019. Meta-analysis of all samples (a total of 1417 cases and 20 402 controls) identified two novel loci significantly associated with NKTCL: IL18RAP on 2q12.1 (rs13015714; p=2·83 × 10−16; odds ratio 1·39 95% CI 1·28–1·50) and HLA-DRB1 on 6p21.3 (rs9271588; 9·35 × 10−26 1·53 1·41–1·65). Fine-mapping and experimental analyses showed that rs1420106 at the promoter of IL18RAP was highly correlated with rs13015714, and the rs1420106-A risk variant had an upregulatory effect on IL18RAP expression. Cell growth assays in two NKTCL cell lines (YT and SNK-6 cells) showed that knockdown of IL18RAP inhibited cell proliferation by cell cycle arrest in NKTCL cells. Haplotype association analysis showed that haplotype 47F-67I was associated with reduced risk of NKTCL, whereas 47Y-67L was associated with increased risk of NKTCL. These two positions are component parts of the peptide-binding pocket 7 (P7) of the HLA-DR heterodimer, suggesting that these alterations might account for the association at HLA-DRB1, independent of the previously reported HLA-DPB1 variants.
Our findings provide new insights into the development of NKTCL by showing the importance of inflammation and immune regulation through the IL18–IL18RAP axis and antigen presentation involving HLA-DRB1, which might help to identify potential therapeutic targets. Taken in combination with additional genetic and other risk factors, our results could potentially be used to stratify people at high risk of NKTCL for targeted prevention.
Guangdong Innovative and Entrepreneurial Research Team Program, National Natural Science Foundation of China, National Program for Support of Top-Notch Young Professionals, Chang Jiang Scholars Program, Singapore Ministry of Health's National Medical Research Council, Tanoto Foundation, National Research Foundation Singapore, Chang Gung Memorial Hospital, Recruitment Program for Young Professionals of China, First Affiliated Hospital and Army Medical University, US National Institutes of Health, and US National Cancer Institute.
Although combination therapy is the standard of care for relapsed/refractory non-Hodgkin's lymphoma (RR-NHL), combination treatment chosen for an individual patient is empirical, and response rates ...remain poor in individuals with chemotherapy-resistant disease. Here, we evaluate an experimental-analytic method, quadratic phenotypic optimization platform (QPOP), for prediction of patient-specific drug combination efficacy from a limited quantity of biopsied tumor samples. In this prospective study, we enrolled 71 patients with RR-NHL (39 B cell NHL and 32 NK/T cell NHL) with a median of two prior lines of treatment, at two academic hospitals in Singapore from November 2017 to August 2021. Fresh biopsies underwent ex vivo testing using a panel of 12 drugs with known efficacy against NHL to identify effective single and combination treatments. Individualized QPOP reports were generated for 67 of 75 patient samples, with a median turnaround time of 6 days from sample collection to report generation. Doublet drug combinations containing copanlisib or romidepsin were most effective against B cell NHL and NK/T cell NHL samples, respectively. Off-label QPOP-guided therapy offered at physician discretion in the absence of standard options (
= 17) resulted in five complete responses. Among patients with more than two prior lines of therapy, the rates of progressive disease were lower with QPOP-guided treatments than with conventional chemotherapy. Overall, this study shows that the identification of patient-specific drug combinations through ex vivo analysis was achievable for RR-NHL in a clinically applicable time frame. These data provide the basis for a prospective clinical trial evaluating ex vivo-guided combination therapy in RR-NHL.
Monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) is a type of rare aggressive lymphoma accounting for 5.4% of primary intestinal peripheral T-cell lymphoma and 10-25% of all primary ...intestinal lymphoma. MEITL also has an extremely poor prognosis with the median overall survival of only seven months. No effective treatment or targeted therapies are currently available to manage this disease. Therefore, there is an urgent need to devise and establish an appropriate preclinical model for a better understanding of this disease and for new therapeutic strategies to be developed on it.
Here, we present the first MEITL patient derived xenograft (PDX) as both orthotropic intestinal and as a subcutaneous model. The histological analysis demonstrated high similarity in the overall immunomorphologic features between the primary tumour and PDX tumours. Importantly, all the PDX tumors carried the distinctive MEITL immunophenotype; CD3+CD4-CD8+CD56+ and extensive nuclear expression of MATK. We also had Sanger sequenced 83 somatic mutations in the original tumour and rediscovered them in the 6th passage of our xenografts, which suggest that the generated MEITL PDX tumours were genetically stable.
Moreover, whole exome sequencing results showed that the clonal architecture in the primary tumour was well preserved in the PDX tumours. The clonal architecture was further analysed with single cell whole genome amplification following by Sanger sequencing. We found that the most of heterozygous mutations in the primary tumour were a mixture of wild type alleles and heterozygous/homozygous mutations from separated clones, including DUPS14 heterozygous mutation (p.R300W) which was known to activate MEK pathway, and SETD2 mutations, (g.chr3:47061285_ 47061286insA and g.chr3:47127805C>A) which were the synthetic lethal partner of Wee1. Interestingly, we found that the two SETD2 mutations alone were able to differentiate three subclones. This result indicates that the tumour was highly subclonal, which could have a strong impact on the selection of drug resistant clones in the drug treatment.
In order to verify this hypothesis, we proceeded to test the efficacy of MEK inhibitor, Trametinib and Wee1 inhibitor, AZD1775 both separately and combined treatment, in our PDX subcutaneous model. The results showed that both 1mg/kg/day of Trametinib and 60mg/kg/day of AZD1775 treatments significantly delayed 60-70% of tumour growth as compared with the vehicle group. The tumour growth was completely arrested in the combined treatment group. In addition, 20% and 40% of the mice exhibited Trametinib and AZD1775 resistance, respectively. From our genomic analysis, all DUPS14 and SETD2 mutations from the pretreated tumours were preserved in the treatment-resistant tumours but absent in the sensitive post-treated residual tumours. The clonality analysis from the sequencing data of the pretreated tumour supports and suggests that single-agent regimes will often not be able to induce a complete response in MEITL patients.
Altogether, the current results demonstrated that our MEITL PDX model preserved the principal histological and genetic characteristics of its original tumour and is genomic stable across passages. The model also showed that MEITL could be highly subclonal and combined targeted therapy might achieve a higher efficacy for MEITL treatment.
No relevant conflicts of interest to declare.
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