Subtype Of Diffuse Large B-cell Lymphoma Research Articles

Repurposing NAMPT inhibitors for germinal center B-cell-like diffuse large B-cell lymphoma.

Diffuse Large B-cell lymphoma (DLBCL) includes the Activated B-cell-like (ABC) and Germinal Center B-cell-like (GCB) subtypes, which differ in cell-of-origin, genetics and clinical response. By screening the subtype-specific activity of 211 drugs approved or in active clinical development for other diseases, we identified inhibitors of nicotinamide phosphoribosyl transferase (NAMPTi) as active in a subset of GCB-DLBCLs in vitro and in vivo. We validated three chemically distinct NAMPTi for their on-target activity based on biochemical and genetic rescue approaches, and found the ratio between NAMPT:PARP1 RNA levels was predictive of NAMPTi sensitivity across DLBCL subtypes. Notably, the NAMPT:PARP1 transcript ratio predicts higher anti-tumor activity in BCL2-translocated GCB-DLBCL. Accordingly, pharmacological and genetic inhibition of BCL2 was potently synergistic with NAMPT blockade. These data support the inhibition of NAMPT as a therapeutically relevant strategy for BCL2-translocated DLBCLs.

EZB-type diffuse large B-cell lymphoma cell lines have superior migration capabilities compared to MCD-type.

Diffuse large B-cell lymphoma (DLBCL) represents the most prevalent aggressive B-cell lymphoma. The group is heterogeneous and the outcome is variable. A variety of approaches have been employed with the objective of improving the stratification of DLBCL patients according to their prognosis, based on the cell of origin. Recently, distinct genetic subtypes of DLBCL have been identified. Given the importance of cell migration in immune cells, the objective of this study was to ascertain whether different genetic subtypes of DLBCL exhibit disparate migration abilities. MCD- and EZB-type DLBCL cell lines were subjected to testing to ascertain their basal velocity in straight microchannels and their ability to overcome tight constrictions of 2 μm. The EZB-type cell lines showed superior basal migration velocity and constriction passage time, and a similar trend was observed in live cell imaging of native human DLBCL tissue. In addition, MCD-type DLBCL exhibited significantly elevated levels of nuclear lamin A/C, which is responsible for the stiffness of the nuclear envelope and could thus explain the disparate migration behaviours observed among these subtypes. Our study suggests that different genetic subtypes of DLBCL may not only influence the outcome after therapy but also the motility of the tumour cells.

DA-R-EPOCH May Mitigate the Adverse Prognostic Implication of the Diagnosis-to-Treatment Interval (DTI) in Large B-Cell Lymphomas

BackgroundShort diagnosis-to-treatment interval (DTI) is associated with high-risk disease and poor survival in diffuse large B-cell lymphoma (DLBCL). There is a paucity of literature on DTI and survival in DLBCL treated with first-line DA-R-EPOCH. We hypothesized that rapid initiation of DA-R-EPOCH in aggressive and high-risk DLBCL mitigates the adverse prognostic implication of short DTI. Patients and MethodsWe retrospectively examined the association of DTI, categorically (short DTI ≤ 14 and long > 14 days) and continuously, with clinical features and survival outcomes in DLBCL treated with first-line DA-R-EPOCH at our institution. ResultsA total 190 patients were analyzed, 21% with high-grade DLBCL subtypes, 56% IPI ≥ 3, and median DTI of 13 days. The short DTI cohort contained more patients with IPI ≥ 3, bulky disease, and elevated LDH. When analyzed categorically and continuously, DTI was not associated with significant differences in PFS or OS. There was significant multivariable interaction between bulky disease, DTI, and PFS (P = .033), with improved PFS in patients with bulky disease in the short DTI cohort. ConclusionWe found that negative prognostic implications of DTI are mitigated in DLBCL patients treated with first-line DA-R-EPOCH, suggesting that urgent initiation of DA-R-EPOCH in high-risk DLBCL, including bulky disease, may improve survival. Our study's shorter DTI compared with DTIs reported in prospective DLBCL trials highlights DTI as a marker of external validity in clinical trial results. Future trials should implement protocols encouraging shorter, realistic DTIs to avoid selection bias against high-risk patients who are unable to delay treatment.

Efficacy and safety analysis of the OR-CHOP regimen for the treatment of MCD subtype diffuse large B cell lymphoma in the real-world setting

Objective: To investigate the efficacy and safety of orelabrutinib combined with R-CHOP in the treatment of MCD subtype diffuse large B cell lymphoma (DLBCL) . Methods: Twenty-three MCD subtype patients whose gene-subtype classification was based on baseline tumor tissue and/or baseline plasma using the LymphGen algorithm from June 2022 to June 2023 in the First Affiliated Hospital of Nanjing Medical University were retrospectively enrolled in the analysis. All patients were treated with R-CHOP or R-miniCHOP in Course 1, OR-CHOP or OR-miniCHOP (21 days for one course) in Courses 2-6, and R-monotherapy in Courses 7-8. Results: Of the 23 patients, the median age was 58 years (range: 30-81 years), and 11 (47.8% ) aged >60 years. Fifteen cases (65.2% ) had international prognostic index (IPI) scores of 3 to 5. The top 10 mutated genes in the gDNA tissues were PIM1 (78.3% ), MYD88 (69.6% ), ETV6 (43.5% ), BTG1 (39.1% ), CD79B (43.5% ), HIST1H1E (39.1% ), BTG2 (34.8% ), KMT2D (30.4% ), CD58 (26.1% ), and CDKN2B (21.7% ). The consistency rate of the tissue and plasma mutations was 80%, while the baseline plasma ctDNA burden was closely correlated with the LDH levels and IPI scores (P<0.05). All patients received 5 courses of OR-CHOP regimens. The mid-term (after 3 courses) evaluation showed that the overall response rate (ORR) was 100% (23/23), with 22 patients (95.65% ) achieving complete remission (CR), and 1 patient (4.35% ) achieving partial remission (PR). The ORR after the end of treatment (EOT) was 95.65% (22/23). Moreover, 21 patients (91.30% ) obtained CR, 1 patient (4.35% ) obtained PR, and 1 patient (4.35% ) obtained progression disease (PD). Of the 21 patients who had the dynamic EOT-ctDNA burden, only four patients (19.0% ) did not achieve EOT-ctDNA clearance, while the other 17 patients (81.0% ) achieved EOT-ctDNA clearance. The median follow-up time was 20.8 (15.3-30.0) months, while the median progression-free survival (PFS) and overall survival (OS) were not reached. The 2-year PFS rate was 71.8% (95% CI 54.7% -94.2% ), while the 2-year OS rate was 91.3% (95% CI 80.5% -100.0% ). Furthermore, the OR-CHOP regimen was generally well tolerated during clinical use, with hematological toxicity being the main adverse effect. Conclusion: This study revealed that the OR-CHOP regimen can be used as an effective and safe first-line treatment for MCD subtype DLBCL.

TCP1 expression alters the ferroptosis sensitivity of diffuse large B-cell lymphoma subtypes by stabilising ACSL4 and influences patient prognosis

Diffuse large B-cell lymphoma (DLBCL), an invasive lymphoma with substantial heterogeneity, can be mainly categorised into germinal centre B-cell-like (GCB) and non-GCB subtypes. DLBCL cells are highly susceptible to ferroptosis, which offers an effective avenue for treating recurrent and refractory DLBCL. Moreover, various heat shock proteins are involved in regulating the sensitivity of tumour cells to ferroptosis. Among these proteins, tailless complex polypeptide 1 (TCP1), a subunit of chaperonin-containing T-complex protein-1 (CCT), plays a role in tumour proliferation and survival. Therefore, we explored the role of TCP1 in different DLBCL subtypes, the sensitivity of GCB and non-GCB subtypes to the ferroptosis inducer RAS-selective lethal small molecule 3 (RSL3), and the underlying molecular mechanism. In GCB cells, TCP1 promoted RSL3-induced ferroptosis. Notably, TCP1 could bind with acyl-CoA synthetase long-chain family member 4 (ACSL4), a key enzyme regulating lipid composition and facilitating ferroptosis, to reduce its ubiquitination and degradation. This interaction activated the ACSL4/LPCAT3 signalling pathway and promoted ferroptosis in the GCB subtype. However, in the non-GCB subtype, TCP1 did not act as a positive regulator but served as a predictor of an unfavourable prognosis in patients with non-GCB. In conclusion, our results suggest that in DLBCL, high TCP1 expression enhances the sensitivity of GCB tumour cells to ferroptosis and serves as a marker of poor prognosis in patients with non-GCB DLBCL.

Clinical characteristics and outcome of early-stage diffuse large B cell lymphoma of female genital track: A retrospective study of the Hellenic cooperative lymphoma group.

Involvement of female genital track (FGT) by diffuse large B cell lymphoma (DLBCL) represents an extremely rare diagnosis. Especially data regarding early-stage disease (i.e., IE, IIE) is very limited. Importantly, previous studies showed controversial results about the risk of central nervous system (CNS) relapse in this entity. Herein, we describe one of the largest reported real-world series of patients with early-stage FGT DLBCL aiming to investigate the clinicopathological characteristics, response to therapy and survival outcomes in the era of immunochemotherapy. We analyzed 21 consecutive patients with biopsy proven DLBCL from uterus or ovary classified as stage IE or IIE out of 1905 newly diagnosed DLBCL patients (1.1%). Uterine and ovarian localization was observed in 14 and seven patients, respectively. Median age was 66years (range 33-96); 9/21 (43%) were <55years. Regarding Cell of Origin DLBCL subtype, Germinal Center B-cell subtype was found in seven patients, non-GCB in 10 and non-classified in 4 patients. Median follow-up was 57months and 5-year overall survival, lymphoma specific survival and Freedom from Progression were 78%, 89% and 90%, respectively. There was no correlation of patients' characteristics with survival parameters. Interestingly, none of the patients experienced CNS relapse. Our results indicate that localized FGT DLBCL exhibits a good prognosis and may not increase the risk for secondary CNS involvement.

An immunohistochemical study of diffuse large B-cell lymphoma with molecular subtyping based on Hans algorithm.

Diffuse large B-cell lymphoma (DLBCL) is the most common type of B-cell lymphoma accounting for about 40% of all lymphomas. The international prognostic index (IPI), which relies on clinical and laboratory parameters, is used as a prognostic tool in DLBCL. In this study, we have included cases of DLBCL not otherwise specified (NOS) type to test the usefulness of the biological subclassification of DLBCL by immunohistochemistry (IHC) using the Hans algorithm into the germinal center B-like (GCB) type and nongerminal center (non-GCB) type. We correlated the subtypes with the demographics, site of involvement, IPI scores, and stage. 1. To study the immunohistochemical profile of DLBCL. 2. To classify patients with DLBCL into germinal center and nongerminal center subtypes. 3. To review the clinical presentations, clinical staging, and follow-up data in cases of DLBCL. A total of 152 cases of DLBCL reported from January 2010 to March 2018 were included in this study. Clinical data, treatment details, and follow-up were reviewed. Apart from the routine IHC markers for DLBCL, additional markers CD10, BCL6, and MUM 1 were performed to classify DLBCL into GCB type and non-GCB type using the Hans algorithm. The median age of presentation was 53 years with male-to-female ratio of 2:1. Most of the patients presented with nodal involvement (56.6%); cervical lymph node is the most common site (46.5%). The majority of the patients presented in Ann Arbor stage 1 (44.8%). According to the international prognostic index, 34.8% had a score of 3 (high intermediate). After IHC studies, GCB subtype (51.5%) of DLBCL emerged as more common than non-GCB type (48.5%). The two subtypes differed significantly with regard to sex (i.e. GCB type was more common in males and non-GCB type in females) and showed no significance with regard to any of the other clinical features and prognostic parameters evaluated. Our study showed that IHC was a useful tool to subclassify DLBCL into GCB and non-GCB subtypes and may be easily incorporated in routine clinical practice.

Plasma circulating tumour DNA is a better source for diagnosis and mutational analysis of IVLBCL than tissue DNA.

Diagnosis of intravascular large B-cell lymphoma (IVLBCL) is a challenge due to its heterogeneous clinical presentation and lack of specific markers. This retrospective study investigated the utility of circulating tumour DNA (ctDNA) sequencing for diagnosing IVLBCL and analysing its mutation landscape. A cohort of 34 IVLBCL patients enrolled and underwent plasma ctDNA targeted sequencing. The median plasma ctDNA concentration was 135.0 ng/mL, significantly higher than that in diffuse large B-cell lymphoma (DLBCL) controls. Correlations were found between ctDNA concentration and disease severity indicators, LDH and SF. Mutation analysis revealed frequent mutations in B-cell receptor and NF-κB signalling pathways, including MYD88 (56%), CD79B (44%), TNFAIP3 (38%) and IRF4 (29%). CNS involvement was significantly related with BCL6 and CD58 mutation. Patients with complicated hemophagocytic lymphohistiocytosis had significantly higher mutation rates in B2M. Comparison with DLBCL subtypes showed distinctive mutation profiles in IVLBCL. Moreover, plasma ctDNA detected more mutations with higher variant allele fraction than tissue DNA, suggesting its superiority in sensitivity and accessibility. Dynamic monitoring of ctDNA during treatment correlated with therapeutic responses. This study revealed the role of ctDNA in IVLBCL diagnosis, mutation analysis, and treatment monitoring, offering a promising avenue for improving patient diagnosis in this rare lymphoma subtype.

Combination Targeted Therapy in Relapsed Diffuse Large B-Cell Lymphoma

BackgroundThe identification of oncogenic mutations in diffuse large B-cell lymphoma (DLBCL) has led to the development of drugs that target essential survival pathways, but whether targeting multiple survival pathways may be curative in DLBCL is unknown.MethodsWe performed a single-center, phase 1b–2 study of a regimen of venetoclax, ibrutinib, prednisone, obinutuzumab, and lenalidomide (ViPOR) in relapsed or refractory DLBCL. In phase 1b, which included patients with DLBCL and indolent lymphomas, four dose levels of venetoclax were evaluated to identify the recommended phase 2 dose, with fixed doses of the other four drugs. A phase 2 expansion in patients with germinal-center B-cell (GCB) and non-GCB DLBCL was performed. ViPOR was administered every 21 days for six cycles.ResultsIn phase 1b of the study, involving 20 patients (10 with DLBCL), a single dose-limiting toxic effect of grade 3 intracranial hemorrhage occurred, a result that established venetoclax at a dose of 800 mg as the recommended phase 2 dose. Phase 2 included 40 patients with DLBCL. Toxic effects that were observed among all the patients included grade 3 or 4 neutropenia (in 24% of the cycles), thrombocytopenia (in 23%), anemia (in 7%), and febrile neutropenia (in 1%). Objective responses occurred in 54% of 48 evaluable patients with DLBCL, and complete responses occurred in 38%; complete responses were exclusively in patients with non-GCB DLBCL and high-grade B-cell lymphoma with rearrangements of MYC and BCL2 or BCL6 (or both). Circulating tumor DNA was undetectable in 33% of the patients at the end of ViPOR therapy. With a median follow-up of 40 months, 2-year progression-free survival and overall survival were 34% (95% confidence interval [CI], 21 to 47) and 36% (95% CI, 23 to 49), respectively.ConclusionsTreatment with ViPOR was associated with durable remissions in patients with specific molecular DLBCL subtypes and was associated with mainly reversible adverse events. (Funded by the Intramural Research Program of the National Cancer Institute and the National Center for Advancing Translational Sciences of the National Institutes of Health and others; ClinicalTrials.gov number, NCT03223610.)

Molecular Subtypes and the Role of TP53 in Diffuse Large B-Cell Lymphoma and Richter Syndrome.

Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoid malignancy and a heterogeneous entity comprised of several biologically distinct subtypes. Recently, novel genetic classifications of DLBCL have been resolved based on common mutational patterns indicative of distinct pathways of transformation. However, the complicated and costly nature of the novel classifiers has precluded their inclusion into routine practice. In view of this, the status of the TP53 gene, which is mutated or deleted in 20-30% of the cases, has emerged as an important prognostic factor for DLBCL patients, setting itself apart from other predictors. TP53 genetic lesions are particularly enriched in a genetic subtype of DLBCL that shares genomic features with Richter Syndrome, highlighting the possibility of a subset of DLBCL arising from the transformation of an occult chronic lymphocytic leukemia-like malignancy, such as monoclonal B-cell lymphocytosis. Patients with TP53-mutated DLBCL, including those with Richter Syndrome, have a particularly poor prognosis and display inferior responses to standard chemoimmunotherapy regimens. The data presented in this manuscript argue for the need for improved and more practical risk-stratification models for patients with DLBCL and show the potential for the use of TP53 mutational status for prognostication and, in prospect, treatment stratification in DLBCL.

Carfilzomib plus rituximab, ifosfamide, carboplatin and etoposide (C-RICE) led to higher response, OS, and PFS in patients with transplant-eligible relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL).

7042 Background: The CORAL study highlighted the need to develop novel salvage regimens for R/Rr/r DLBCL previously treated with R+CHOP. Overall response rate (ORR) to second line immuno-chemotherapy was 51% with a 3-year progression free survival (PFS) of 30% following high-dose chemotherapy and autologous stem cell support (HDC-ASCS). Optimal disease control (complete remission [CR] or partial remission [PR]) prior to HDC-ADCS and more recently to chimeric antigen receptor T-cell therapy (CAR T), correlates with improved outcomes. Dysregulation of Bcl-2 family members has been associated with acquired resistance to rituximab and chemotherapy which we have previously shown may be mitigated by co-treatment with proteasome inhibition in pre-clinical model. Subsequently, we conducted a Phase I/II clinical trial evaluating the safety and efficacy of CRICE as salvage therapy for R/R DLBCL (Blood Adv. 2023 7:1146-1155). Methods: Here we retrospectively compared the clinical outcomes of R/R DLBCL patients treated with CRICE (N=28) versus RICE (N=38) on our prior clinical trial (NCT01959698). Demographic, clinical, and pathological characteristics were collected for both groups (Table). Study endpoints consisted of differences in overall response rate (ORR), CR/PR rates, median progression free survival (PFS) and overall survival (OS) between the two cohorts. Results: The addition of Carfilzomib to RICE resulted in improved clinical outcomes. A higher ORR (92.9 vs 76.3, P=0.073) and CR rates (82.1 vs. 44.7, P=0.002) were observed in CRICE vs. RICE treated patients. Multivariate analysis confirmed the higher CR rates in CRICE vs. RICE when adjusted by DLBCL subtype (GCB vs. nNon-GCB, P=0.003). More CRICE patients proceeded to HDC-ASCS (52.6% vs. 47.4%, P=0.618). The 3yr PFS rate was higher in CRICE (54%, 32-72%) vs. RICE treated patients (35%, 19-51%). While the median PFS was longer in CRICE treated patients 36.8m (0.8, 73.2) vs. 3.2m (0.5, 54.2) (RICE), it did not reach statistical significance (P=0.714). No differences in OS were observed between CRICE &amp; RICE patients, median OS 67.3m vs. 71.8m. Conclusions: The CRICE outcomes were more striking in patients with non-GCB r/r DLBCL (ORR 85%, mPFS and OS not reached). CRICE led to high CR rates and longer PFS among r/r DLBCL patients, especially in non-GCB DLBCL patients. CRICE could be an attractive regimen to achieve disease control in r/r DLBCL patients undergoing consolidation therapy with HDC-ASCT or CAR T-cell therapy. [Table: see text]

Incidence of any infections and SARS-CoV-2 infections in patients receiving treatment for follicular lymphoma and diffuse large B-cell lymphoma: Real-world evidence from a large US national claims database.

e19061 Background: Non-Hodgkin’s lymphoma is a heterogeneous group of conditions, including the indolent subtype follicular lymphoma (FL) and the aggressive subtype diffuse large B-cell lymphoma (DLBCL). Infections associated with NHL are a major concern due to effects of the underlying disease and its treatment and have been reported to increase with increasing lines of therapy (LoT). However, the risk of infections overall and SARS-COV-2 infections specifically is not well characterized in patients who have received multiple LoTs. The goal of the study was to estimate the exposure-adjusted incidence rates (EAIR) of infections during the COVID-19 pandemic by type, severity and LoT received in patients treated for FL or DLBCL in the real-world setting. Methods: We identified patients in the Optum Clinformatics claims data from October 1, 2015, to June 30, 2023. Patients were aged ≥18 years, enrolled continuously for 365 days before index (start of LoT), and had ≥2 ICD-10 diagnosis codes for FL or DLBCL in the 365 days before index. The EAIR (per 100 person-years, PY) was estimated for infections by type (any infections and SARS-COV-2 [after 1/1/2020]), severity (hospitalized or fatal hospitalizations), and number of LoTs received. Results: A total of 4,799, 1,025 and 510 FL patients were included in the 1L (1 LoT), 2L, and 3L+ cohorts, respectively. The EAIR of infections resulting in hospitalization in 1L, 2L, and 3L+ cohorts were 20.6 (95% confidence interval (CI): 19.0-22.3), 30.2 (25.5-35.9), and 44.2 (35.4-55.3) per 100-PY for any infection; and 4.6 (4.0-5.4), 4.4 (3.0-6.5) and 8.3 (5.3-13.2) per 100-PY for SARS-COV-2 infections, respectively. The EAIR of fatal hospitalizations were 4.0 (3.4-4.8), 8.6 (6.4-11.5), and 13.9 (9.7-20.0) per 100-PY for any infection; and 1.3 (1.0-1.7), 1.6 (0.8-3.0), and 4.1 (2.2-7.9) per 100-PY for SARS-COV-2 infections. A total of 8,058, 2,114 and 977 DLBCL patients were included in 1L, 2L, and 3L+ cohorts, respectively. The EAIR of infections resulting in hospitalization in 1L, 2L, and 3L+ cohorts were 64.2 (60.7-67.8), 85.2 (76.9-94.3), and 113.4 (98.4-130.7) per 100-PY for any infection; and 6.3 (5.5-7.2), 7.3 (5.6-9.6), and 15.1 (11.3-20.2) per 100-PY for SARS-COV-2 infections respectively. The EAIR of fatal hospitalizations were 12.0 (10.8-13.3), 23.0 (19.5-27.1), and 27.8 (22.1-34.9) per 100-PY for any infection; and 1.6 (1.2-2.1), 2.7 (1.7-4.2), and 4.8 (2.9-8.0) per 100-PY for SARS-COV-2 infections in 1L, 2L and 3L+ cohorts, respectively. Conclusions: This real-world analysis demonstrated substantial morbidity and mortality associated with overall and SARS-COV-2 infections among NHL patients, with a higher incidence in DLBCL compared to FL, and with increasing LoTs.

Clinical Features and Prognosis of Patients with CD5+ Diffuse Large B-Cell Lymphoma

To analyze the clinical characteristics and prognosis of patients with CD5+ diffuse large B-cell lymphoma (DLBCL). The clinical data of 161 newly treated DLBCL patients in Gansu Provincial Hospital from January 2013 to January 2020 were retrospectively analyzed. According to CD5 expression, the patients were divided into CD5+ group and CD5- group. The clinical characteristics and prognosis of the two groups were statistically analyzed. The median age of patients in CD5+ group was 62 years, which was higher than 56 years in CD5- group (P =0.048). The proportion of women in CD5+ group was 62.96%, which was significantly higher than 41.79% in CD5- group (P =0.043). The proportion of patients with IPI score > 2 in CD5+ group was 62.96%, which was higher than 40.30% in CD5- group (P =0.031). Survival analysis showed that the median overall survival and progression-free survival time of patients in CD5+ group were 27(3-77) and 31(3-76) months, respectively, which were both shorter than 30(5-84) and 32.5(4-83) months in CD5- group (P =0.047, P =0.026). Univariate analysis showed that advanced age, positive CD5 expression, triple or double hit at initial diagnosis, high IPI score and no use of rituximab during chemotherapy were risk factors for the prognosis of DLBCL patients. Further Cox multivariate regression analysis showed that these factors were also independent risk factors except for advanced age. CD5+ DLBCL patients have a worse prognosis than CD5- DLBCL patients. Such patients are more common in females, with advanced age and high IPI score, which is a special subtype of DLBCL.

Cerebellum/liver index on baseline 18F-FDG PET/CT to improve prognostication in post-transplant lymphoproliferative disorders: a multicenter retrospective study

BackgroundBesides International Prognostic Index (IPI) score, baseline prognostic factors of post-transplant lymphoproliferative disorders (PTLD) are poorly identified due to the rarity of the disease. New indexes derived from healthy organ uptake in baseline 18F-FDG PET/CT have been studied in immunocompetent lymphoma patients. The aim of this study is to evaluate the performances of the cerebellum-to-liver uptake ratio (denoted as CLIP) as a prognostic factor for PFS and OS. This retrospective multicenter study is based on patients with PTLD included in the K-VIROGREF cohort. The previously published threshold of 3.24 was used for CLIP in these analyses.ResultsA total of 97 patients was included with a majority of monomorphic diffuse large B-cell lymphoma subtype (78.3%). Both IPI score (≥ 3) and CLIP (< 3.24) were significant risk factors of PFS with corresponding hazard ratios of 2.0 (1.0–4.0) and 2.4 (1.3–4.5) respectively. For OS, CLIP was not significant and resulted in a hazard ratio of 2.6 (p = 0.059). Neither IPI score or Total Metabolic Tumor Volume reached significance for OS.ConclusionCLIP is a promising predictor of PFS and perhaps OS in PTLD. Further prospective studies are needed to confirm these results.

Abstract 2265: Distinct alternative splicing patterns in genetic subtypes of diffuse large B-cell lymphoma

Abstract Advances in sequencing techniques have made molecular subgrouping of Diffuse Large B-cell Lymphoma (DLBCL) based on DNA cahnges, which has led to the development of Lymphgen classification. By the way, although alternative splicing (AS) in cancer cells contributes to proliferation, invasion and metastasis, and immune escape, their role and association with DLBCL molecular subtypes are unknown. Therefore, we analyzed whole-exome sequencing (WES) and bulk RNA-Seq data paired in the public EGA dataset (EGAD00001003600) to explore the patterns of AS events that differ between Lymphgene subtypes. The WES data of 620 DLBCL samples that passed quality control were aligned to the reference using BWA-MEM, and variants were called with Mutect2. We used the information of copy number variants provided by cBioPortal. The RNA-Seq analysis was performed using the STAR-RSEM pipeline and differential splicing events were detected using rMATS to compare subtypes. Among 620 DLBCL samples, there were 19 MCDs, 95 EZBs, 22 BN2s, and 137 ST2s (50 samples with multiple genetic classes, and 291 samples unclassified). Mutations in spliceosome complex genes (ZRSR2 and SF1) were found in 14 and 27 samples, respectively. In BN2 and MCD subtypes, splicing events with significantly different exon inclusion levels were observed at a high frequency of 29 and 16 occurrences, respectively, compared to other subtypes. (P-value &amp;lt; 0.05). In contrast, retained intron is the only event observed in the EZB subtype (Table 1). Samples with mutations in ZRSR2 and SF1 showed four and two aberrant events, respectively, compared to samples without these mutations. Of note, rMATS detected an alternative 3’ splice site event in exon 6 of CD37 in the MCD. CD37 is involved in tumorigenesis in leukocytes and has been suggested as a potential biomarker in blood cancer, and its dysregulation may have influenced the poor prognosis of MCD. In summary, molecular subtypes of DLBCL had unique features in terms of alternative splicing. Functional consequences of these selective exon usages for each DLBCL subtype are being warranted. Citation Format: Sanyeowool An, Youngil Koh, Sung-Soo Yoon. Distinct alternative splicing patterns in genetic subtypes of diffuse large B-cell lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2265.

Artesunate induces ferroptosis by regulating MT1G and has an additive effect with doxorubicin in diffuse large B-cell lymphoma cells

Diffuse Large B-cell lymphoma (DLBCL) is a highly aggressive disease with heterogeneous outcomes and marked variability in the response to chemotherapy. DLBCL comprises two major subtypes: germinal centre B-cell-like (GCB) and activated B-cell-like (ABC). Our study highlights the extensive antitumour activity of artesunate (ART) against both major DLBCL subtypes. Transcriptome analysis suggests the potential involvement of ferroptosis in artesunate-induced cell death. Because of low glutathione (GSH) and glutathione peroxidase 4 (GPX4) levels, along with the accumulation of free iron (Fe2+), artesunate induces the excessive production of reactive oxygen species (ROS), ultimately leading to ferroptosis, a form of cell death driven by phospholipid peroxidation. A putative target of artesunate, metallothionein 1G (MT1G), was selected for further analysis. Subsequent studies revealed that inhibiting MT1G expression in vitro significantly impedes the ferroptosis-promoting activity of artesunate by reducing lipid peroxidation and iron accumulation. We also showed that the combination of artesunate and doxorubicin had a marked additive inhibitory effect on GCB and ABC DLBCL cells. In conclusion, artesunate induces ferroptotic death in GCB and ABC DLBCL cells by attenuating the GPX4/GSH antioxidant defence system and increasing intracellular iron levels, indicating its therapeutic potential for relapsed or refractory DLBCL.

Epstein-Barr virus-positive iris diffuse large B-cell lymphoma detected by metagenomic next-generation sequencing

PurposeEpstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL) is a relatively rare subtype of DLBCL. Herein, we report a case of a patient with EBV-positive iris DLBCL after undergoing penetrating keratoplasty and discuss its possible pathogenesis.MethodsA 72-year-old male patient presented to our hospital with progressive blurring of vision in the left eye for the past 4 months. Small white nodular lesions were observed on the iris and retinal surface of the left eye, with a white cloud-like opacity in the vitreous cavity.ResultsThe patient was eventually diagnosed with EBV-positive iris DLBCL after undergoing pathological and metagenomic tests. After injecting methotrexate in the left vitreous cavity and administering systemic and local antiviral treatments, the ocular lesions disappeared.ConclusionEBV infection, drug immunosuppression, and aging-related immune deterioration may play significant roles in the pathogenesis of EBV-positive iris DLBCL.SynopsisEpstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL) is a new subtype of DLBCL, which rarely occurs. Herein, we report a case of a patient with EBV-positive iris DLBCL after undergoing penetrating keratoplasty and discuss its possible pathogenesis.

Epiregulin: A new prognostic molecule in non-Hodgkin lymphoma.

Epiregulin is a molecule that plays a role in cell proliferation, tumor development, inflammation, and angiogenesis in malignant diseases. Our study aims to reveal, for the first time, the predictive value of this molecule in non-Hodgkin lymphoma (NHL) and its association with disease stage, cell type, and extranodal involvement. The study is an observational case-control trial involving 60 newly diagnosed NHL patients and 60 healthy individuals (control group) between 18 and 75years old. Demographic characteristics of all volunteers, stages of patients' illnesses and lymphoma cell types, hemogram, biochemistry tests, beta 2-microglobulin, C-reactive protein (CRP), and epiregulin levels were measured and statistically evaluated. Epiregulin levels were significantly higher in NHL patients compared to the control group (P < 0.0001). Similarly, a significant increase in epiregulin levels was observed in advanced NHL patients. Furthermore, the most common NHL subgroup within the NHL group, diffuse Large B Cell Lymphoma (DLBCL), and the subgroup with extranodal involvement also had significantly higher levels of epiregulin. A positive correlation was found between the epiregulin molecule and CRP, beta 2-microglobulin, and lactate dehydrogenase (LDH) levels in NHL patients. Our study suggests that serum epiregulin levels, discovered to increase in NHL patients for the first time, may be an independent predictive molecule in an advanced stage, extranodal involvement, and the DLBCL subtype of this disease. Epiregulin positively correlates with prognostic molecules such as beta 2-microglobulin, LDH, and CRP. Illuminating its potential role in NHL pathogenesis could make epiregulin a vital drug target for treatment.

Response to Bruton’s tyrosine kinase inhibitors in aggressive lymphomas linked to chronic selective autophagy

Diffuse large B cell lymphoma (DLBCL) is an aggressive, profoundly heterogeneous cancer, presenting a challenge for precision medicine. Bruton's tyrosine kinase (BTK) inhibitors block B cell receptor (BCR) signaling and are particularly effective in certain molecular subtypes of DLBCL that rely on chronic active BCR signaling to promote oncogenic NF-κB. The MCD genetic subtype, which often acquires mutations in the BCR subunit, CD79B, and in the innate immune adapter, MYD88L265P, typically resists chemotherapy but responds exceptionally to BTK inhibitors. However, the underlying mechanisms of response to BTK inhibitors are poorly understood. Herein, we find a non-canonical form of chronic selective autophagy in MCD DLBCL that targets ubiquitinated MYD88L265P for degradation in a TBK1-dependent manner. MCD tumors acquire genetic and epigenetic alterations that attenuate this autophagic tumor suppressive pathway. In contrast, BTK inhibitors promote autophagic degradation of MYD88L265P, thus explaining their exceptional clinical benefit in MCD DLBCL.

Diffuse Large B Cell Lymphoma: Immunohistochemical Classification According to Hans Algorithm and Association With Outcome in A Moroccan Institution.

The most prevalent subtype of non-Hodgkin lymphoma is diffuse large B-cell lymphoma (DLBCL). Germinal center B-cell (GCB) and non-germinal center B-cell (non GCB) are the two main biologically different molecular subtypes identified utilizing an immunohistochemistry-based approach. Our objective in this study is to analyze the impact of immunohistochemical subtypes of DLBCL (GCB or non GCB) on demographic and clinicopathological parameters, response to chemotherapy and survival outcomes. This is a retrospective study including 106 cases of DLBCL collected in the department of pathology, Hassan II university hospital, Fez (Morocco), over a period of 12 years (January 2010-September 2022). The subtypes of DLBCLs were defined according to Hans algorithm, using immunohistochemistry by three biomarkers (CD10, BCL6, MUM1). Independent t tests and analyses of variance were used for the comparison of mean values. We employed the SPSS 26.0 program to achieve this. A statistically significant value was set at P < .05. Seventy-five patients (71%) were non-GCB subtype, while thirty-one patients (29%) had the GCB immunosubtype. We have found a significant (P < .05) correlations between DLBCL immunosubtypes and treatment responses on one hand and survival in the other hand. In the GCB subtype, the response rate and survival were significantly improved. A significant association was found between Ki 67 expression and survival on univariate analysis. On multivariate analysis, we note a correlation between Ki 67 expression, DLBCL immunohistochemical subtypes and survival outcome. Non GCB subtype is associated with poor response to treatment and inferior survival outcome compared to GCB subtype in Moroccan context, especially when combined with high expression of Ki 67 marker.