Treatment Of Peripheral T-cell Lymphoma Research Articles

Pyroptotic macrophages promote proliferation and chemotherapy resistance of peripheral T-cell lymphoma via TLR4 signaling pathway.

Peripheral T-cell lymphoma (PTCL) is a highly aggressive type of non-Hodgkin's lymphoma with a poor prognosis. Pyroptosis is a newly discovered procedural cell death mode, which has been implicated to occur in both tumor cells and immune cells. However, the occurrence and effect of pyroptosis on PTCL remain unclear. Here, we found that pyroptosis occurred in interstitial macrophages of PTCL rather than in tumor cells. In clinical specimens, macrophage pyroptosis was associated with a poor prognosis of PTCL. Invitro experiments and gene sequencing results showed that pyroptotic macrophages could upregulate the expression of TLR4 through secreting inflammatory cytokines IL-18. Upregulated TLR4 activated its downstream NF-κB anti-apoptotic signaling pathway, thus leading to malignant proliferation and chemotherapy resistance of tumor cells. Moreover, the expression of factors such as XIAP in the NF-κB anti-apoptotic pathway was downregulated after the knockdown of TLR4, and the malignant promotion effect of pyroptotic macrophages on PTCL cells was also reversed. Our findings revealed the mechanism of pyroptotic macrophages promoting the malignant biological behavior of PTCL and elucidated the key role of TLR4 in this process. In-depth analysis of this mechanism will contribute to understanding the regulatory effect of PTCL by the tumor microenvironment and providing new ideas for the clinical treatment of PTCL.

Romidepsin Plus Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone Versus Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone in Patients With Previously Untreated Peripheral T-Cell Lymphoma: Final Analysis of the Ro-CHOP Trial.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.The primary analysis of the Ro-CHOP phase III randomized controlled trial (ClinicalTrials.gov identifier: NCT01796002) established that romidepsin (Ro) plus cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) did not yield an increased efficacy compared with CHOP alone as first-line treatment of peripheral T-cell lymphoma. We report the planned final analysis 5 years after the last patient enrolled. With a median follow-up of 6 years, median progression-free survival (PFS) was 12.0 months compared with 10.2 months (hazard ratio [HR], 0.79 [95% CI, 0.62 to 1.005]; P = .054), while median overall survival was 62.2 months (35.7-86.6 months) and 43.8 months (30.1-70.2 months; HR, 0.88 [95% CI, 0.68 to 1.14]; P = .324) in the Ro-CHOP and CHOP arms, respectively. In an exploratory analysis, the median PFS in the centrally reviewed follicular helper T-cell lymphoma subgroup was significantly longer in the Ro-CHOP arm (19.5 v 10.6 months, HR, 0.703 [95% CI, 0.502 to 0.985]; P = .039). Second-line treatments were given to 251 patients with a median PFS2 and OS2 after relapse or progression of 3.3 months and 11.5 months, respectively. Within the limits of highly heterogeneous second-line treatments, no specific regimen seemed to provide superior disease control. However, a potential benefit was observed with brentuximab vedotin in association with chemotherapy even after excluding anaplastic large-cell lymphoma subtype or after adjusting for histology and international prognostic index in a multivariate model (HR for PFS, 0.431 [95% CI, 0.238 to 0.779]; P = .005).

NOT OTHERWISE SPECIFIED T-CELL LYMPHOMA: OUTCOMES OF A SINGLE CENTER STUDY.

The peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) is the most common subtype of peripheral T-cell lymphoma (PTCL). It constitutes approximately 25% of all PTCLs and accounts for more than 15% of all lymphomas. The results of the first Ukrainian prospective study of patients with PTCL-NOS are presented in the article. The aim of the study was to analyze the morbidity of PTCL patients and the treatment performed, to evaluate overall survival and progression-free survival, and to determine the factors that predict the treatment response. An analysis was performed on the data of 31 patients diagnosed with peripheral PTCL-NOS from February 2018 to the present. T-cell lymphoid neoplasms were diagnosed according to the 2016 WHO classification. The treatment regimens were in alignment with ESMO and NCCN guidelines. More than 90% of patients were prescribed anthracycline-based regimens (CHOP; CHOEP - cyclophosphamide, doxorubicin, etoposide, vincristine, prednisone). An initial treatment was performed with CHOP-based regimens in 38.70% (n = 12) of patients, with the addition of etoposide in 58.06% of patients (n = 18). The response was assessed according to the response criteria for malignant lymphoma (Cheson, 2008, 2014). The overall response to therapy was 58.06% (n = 18), with complete responses in 29.03% of patients and partial responses in 29.03% of patients. The stabilization of the disease occurred in 3.44%, while the disease progression in 41.37% of patients. The 12-month and 24-month survival rates were 75.44% and 50.81%, respectively. The 12-month and 24-month progression-free survivals were 47.68% and 33.1%, respectively. Ki-67 overexpression (> 65%) was a negative prognostic factor. The results of the treatment of PTCL obtained in a Ukrainian population study are similar to those in other European studies, all of which remain unsatisfactory. Further research is required to develop a new strategy for examination and therapy to improve treatment outcomes. The emphasis should be placed on the pragmatic clinical trials comparing the efficacy of first-line treatment in PTCL patients with both favorable and unfavorable clinical factors.

Aggressive T-cell lymphomas: 2024: Updates on diagnosis, risk stratification, and management.

Aggressive T-cell lymphomas continue to have a poor prognosis. There are over 30 different subtypes of peripheral T-cell lymphoma (PTCL), and we are now beginning to understand the differences between the various subtypes beyond histologic variations. Gene expression profiling and other molecular techniques have enabled deeper understanding of differences in various subtypes as reflected in the latest 5th WHO classification of PTCL. It is becoming increasingly clear that therapeutic approaches that target specific cellular pathways are needed to improve the clinical outcomes of PTCL. There are many targeted agents currently in various stages of clinical trials for PTCL that take advantage of the differential expression of specific proteins or receptors in PTCL tumors. This includes the CD30 directed antibody drug conjugate brentuximab vedotin. Other notable targets are phosphatidylinositol 3-kinase inhibitors, histone deacetylase inhibitors, CD25, and chemokine receptor 4. Anaplastic lymphoma kinase (ALK) inhibitors are promising for ALK expressing tumors. Allogeneic stem cell transplant continues to be the curative therapy for most aggressive subtypes of PTCL. The use of checkpoint inhibitors in the treatment of PTCL is still controversial, with best results seen in cases of extranodal natural killer cell/T-cell lymphoma. Bispecific antibody-based treatments and chimeric antigen receptor cell-based therapies are in clinical trials.

Precise diagnosis and treatment for peripheral T-cell lymphomas: From pathogenic mechanisms to innovative approaches

<p>Peripheral T-cell lymphomas (PTCLs) encompass a diverse group of aggressive non-Hodgkin��s lymphomas originating from mature T lymphocytes. Despite their relatively low prevalence compared to B-cell lymphomas, PTCLs pose significant clinical challenges due to their heterogeneity, lack of specific biomarkers, and often poor response to conventional chemotherapies. Unraveling the intricate pathogenic mechanisms underlying PTCLs is pivotal for the development of targeted therapies, which has become a major focus of PTCL research in recent years. It was previously postulated that genomic alterations play a pivotal role in T-cell transformation and lymphomagenesis. Recent multi-omics investigations and functional studies focusing on pathogenic mechanisms have unveiled that in addition to genetic abnormalities, diverse intrinsic and extrinsic mechanisms are implicated in the pathogenesis of PTCLs. In this Review, we provide an overview of the recent advances in the pathogenesis and management of PTCLs, focusing on the current and potential precise diagnosis and treatment based on intrinsic and extrinsic mechanisms. Bioengineering and drug development have enabled the effective modulation of many previously ��undruggable�� targets, which offers the potential to target new biomarkers associated with PTCL pathogenesis. The integration of artificial intelligence (AI) in clinical practice enables a comprehensive framework, merging diverse data sources and clinical context to discover precise biomarkers for personalized medicine. Finally, we present pressing questions and challenges that demand attention and discuss emerging solutions.</p>

Precise diagnosis and treatment for peripheral T-cell lymphomas: From pathogenic mechanisms to innovative approaches

<p>Peripheral T-cell lymphomas (PTCLs) encompass a diverse group of aggressive non-Hodgkin��s lymphomas originating from mature T lymphocytes. Despite their relatively low prevalence compared to B-cell lymphomas, PTCLs pose significant clinical challenges due to their heterogeneity, lack of specific biomarkers, and often poor response to conventional chemotherapies. Unraveling the intricate pathogenic mechanisms underlying PTCLs is pivotal for the development of targeted therapies, which has become a major focus of PTCL research in recent years. It was previously postulated that genomic alterations play a pivotal role in T-cell transformation and lymphomagenesis. Recent multi-omics investigations and functional studies focusing on pathogenic mechanisms have unveiled that in addition to genetic abnormalities, diverse intrinsic and extrinsic mechanisms are implicated in the pathogenesis of PTCLs. In this Review, we provide an overview of the recent advances in the pathogenesis and management of PTCLs, focusing on the current and potential precise diagnosis and treatment based on intrinsic and extrinsic mechanisms. Bioengineering and drug development have enabled the effective modulation of many previously ��undruggable�� targets, which offers the potential to target new biomarkers associated with PTCL pathogenesis. The integration of artificial intelligence (AI) in clinical practice enables a comprehensive framework, merging diverse data sources and clinical context to discover precise biomarkers for personalized medicine. Finally, we present pressing questions and challenges that demand attention and discuss emerging solutions.</p>

What is new in the treatment of peripheral T-cell lymphomas in the Czech Republic

What is new in the treatment of peripheral T-cell lymphomas in the Czech Republic

Pralatrexate injection combined with CHOP for treatment of PTCL: results from the Fol-CHOP dose-finding phase 1 trial

AbstractPralatrexate is a folate antagonist that selectively enters cells expressing reduced folate carrier type 1 and competitively inhibits dihydrofolate reductase, leading to interruption of RNA synthesis, DNA replication, and apoptosis. This phase 1 study was conducted to evaluate the maximum tolerated dose (MTD) of pralatrexate in combination with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) regimen (part 1) and the response and pharmacokinetics of 6 cycles of this combination (CHOP + Folotyn 30 mg/m2 [Fol-CHOP]) in patients with newly diagnosed peripheral T-cell lymphoma (PTCL). In part 1, on days 1 and 8 of each cycle, patients were treated with 10, 15, 20, 25, or 30 mg/m2 of pralatrexate in combination with CHOP, per dose escalation, in 5 sequential cohorts. No patients experienced DLTs in cohorts 1, 2, 3, 4, and 5. The pralatrexate dose of 30 mg/m2 was selected to be combined with CHOP for part 2 and administered to 33 additional patients in the expansion cohort. At the MTD, the Fol-CHOP regimen was generally well tolerated in patients with PTCL, with an overall response rate (ORR) of 83.9% (20 complete response and 6 partial response), as assessed by treating investigators. Thirty-five patients (67.3%) experienced grade 3/4 treatment-emergent adverse events, the most common of which were anemia (21.2%), neutropenia (19.2%), febrile neutropenia (11.5%), fatigue, mucosal inflammation, nausea, and vomiting (7.7% each). In conclusion, Fol-CHOP was found to be a safe and effective treatment for newly diagnosed PTCL and deemed worthy of further investigation. This trial was registered at www.ClinicalTrials.gov as #NCT02594267.

Patterns of Care and Impact of Initial Treatment in Peripheral T-Cell Lymphoma: Outcome Analysis from the Lymphoma Epidemiology of Outcomes (LEO) and Molecular Epidemiology Resource (MER) Prospective Cohort Study

Background Peripheral T-cell lymphomas (PTCLs) comprise a rare, heterogeneous group of non-Hodgkin lymphomas of mature T-cell origin. Most systemic (s) PTCL subtypes typically have poor outcomes with conventional anthracycline-based chemotherapy. Biomarker-driven and subtype-specific treatments are promising but unmet needs. Few benchmark studies exist to characterize the current real-world landscape of clinical and pathologic practice. We report the patterns of care and updated outcome data for PTCL patients enrolled in the LEO-MER multi-center prospective cohort study (ClinicalTrials.gov NCT02736357). Methods Patients aged 18 years or older with newly diagnosed PTCL were prospectively enrolled in the University of Iowa/Mayo Clinic MER cohort (2002-2015) or the expanded LEO cohort (2015-2020). Clinical, pathology, treatment, and outcome data were abstracted from medical records using a standard protocol in both cohorts. Pathology underwent expert re-review based on WHO criteria. Overall survival (OS) was calculated from date of diagnosis to date of death or last follow-up. Event-free survival (EFS) was calculated from date of diagnosis to disease progression, initiation of 2 nd line therapy, or death from any cause. EFS and OS were evaluated using Cox model and Kaplan-Meier estimator. Log-rank test was used to test the significance of difference between groups. Results LEO-MER enrolled 1132 PTCL patients during the study period (462 MER and 670 LEO). Of these, 722 were sPTCLs (281 MER and 441 LEO), including PTCL-NOS (N=253, 35%), anaplastic large cell lymphoma (ALCL; N=180, 24.9% [74 ALK+, 106 ALK-]), angioimmunoblastic T-cell lymphoma (AITL, N=164, 22.7%), extranodal NK-TCL (N=50, 6.9%), adult T-cell leukemia/lymphoma (N=33, 4.6%), enteropathy-associated TCL (N=19, 2.6%), and hepatosplenic TCL (N=13, 1.8%) ( Table 1). Median age at diagnosis was 60 years. M:F ratio was 1.5. Comparing LEO to MER, African American population was 15.4% vs 0.7%, and Hispanic was 10% vs 2.2%. Clinical characteristics were comparable between MER and LEO overall: PS≥2, 20.9%; elevated LDH, 50.7%; stage III-IV, 67.6%; and IPI 2-5, 65.7%. The most common 1 st line chemotherapy regimens overall were CHOP-based (N=506, 70%), including 60% receiving CHOP-like chemotherapy in both MER and LEO cohorts (CHOP [N=268, 37%], CHOEP [N=91, 13%] or EPOCH [N=75, 10%]), and 16% with CHOP-like in combination with novel agents in LEO cohort (BV+ [N=41, 9.3%], azacitidine+ [N=11, 2.5%], pralatrexate+ [N=10, 2.3%], lenalidomide+ [N=8, 1.9%]) ( Table 1). More patients received etoposide in LEO (40.3%) than in MER (20.3%). 74 patients (10.3%) underwent consolidative SCT following induction chemotherapy (71 auto and 3 allo). 65 patients (11.2%) received frontline therapy on clinical trials. At a median follow-up of 9.4 years in MER and 4 years in LEO, 177 (MER) and 269 (LEO) events, and 150 (MER) and 206 (LEO) deaths were observed, respectively. The 3-year EFS and 4-year OS estimates for sPTCL were 46.3% and 59.1% in MER, and 40.4% and 51.3% in LEO. EFS and OS correlated with IPI scores and differed by sPTCL subtypes ( Figure 1). ALCL had superior survival, with 3-year EFS and 4-year OS of 78.2% and 90.5% for ALK+, and 65.9% and 76.9% for ALK-. Non-ALCL subtypes including PTCL-NOS and AITL had inferior outcomes, with 3-year EFS and 4-year OS of 31.4% and 42.8% for PTCL-NOS, and 33.4% and 50.7% for AITL. In subset analysis, the addition of etoposide to CHOP chemotherapy as either CHOEP or EPOCH was associated with improved OS for ALK- ALCL (p=0.038, log-rank), but not for ALK+ ALCL (p=0.75) or non-ALCL subtypes of PTCL-NOS and AITL (p=0.88). Conclusion The LEO-MER study is the largest prospective cohort study of PTCL to date. Patterns of care in the LEO cohort begin to incorporate novel agents in frontline therapy. Outcomes continue to mature with longitudinal follow-up and ongoing accrual, which poise to shape benchmarks in the contemporary era. The lack of benefit of etoposide adding to CHOP induction and poor overall survival of non-ALCL subtypes underscores the unmet need of therapeutic breakthrough for non-ALCL frontline treatment, particularly through clinical trials with biomarker-guided approaches incorporating novel agents.

Chidamide with Azacitidine and CHOP Treatment Plus Autologous Transplantation,Followed By Maintenance with Chidamide for Patients with Newly Diagnosed Peripheral T-Cell Lymphoma: Interim Analysis of a Prospective,Single Center,Single-Arm, Phase 2 Trial

Background: The standard first-line treatment for peripheral T-Cell Lymphoma (PTCL) is cyclophosphamide, doxorubicin, vincristine, and prednison (CHOP)，but the treatment effect is poor,the 5-year overall survival(OS) was only 30-40%.We aimed to evaluate the efficacy and safety of chidamide with azacitidine and CHOP treatment plus autologous stem-cell transplantation and of maintenance treatment with chidamide in newly diagnosed peripheral T-Cell Lymphoma (PTCL). Methods: This is an ongoing prospective,single center，single-arm, phase 2 trial. We enrolled newly diagnosed PTCL patients (NK/T lymphoma and ALK positive T cell lymphoma were excluded )and used 21-day Chi+AZ-CHOP regimen for induction therapy.Subjects received CHOP on day 1 combined with azacitidine 100mg was subcutaneous injected daily for 5 days and oral chidamide 20mg two times per week of each cycle. 17 subjects received PEG-rhG-CSF Supportive care after treatment.These subjects who evaluated PR or CR remission after 4 to 6 courses of induction therapy will perform autologous hematopoietic stem cell transplantation(ASCT), followed by oral chidamide 20mg two times per week maintance. The primary endpoints is ORR per 2014 IWG criteria.Secondary endpoints include CR, safety and survival. Results:From 3/2021 to 7/2023, 35 subjects with previously untreated PTCL were enrolled in chongqing university cancer hospital, and the study met its accrual.At study entry, 22 patients (62.8%) were angioimmu-noblastic T-cell lymphoma(AITL),4 patients (11.4%) was monomorphic epitheliotropic intestinal T-cell lyphomas(MEITL),3 patients (8.6%) were Peripheral T Cell Lymphoma, Not Otherwise Specified（PTCL-nos），2 patients (5.7%) was Mycosis fungoides(MF),4 patients(11.4%) was anaplastic large cell lymphoma; ALK-negative（ALCL-ALK).The median age was 55 years (range 27-70),and the M:F ratio was 1.5:1. 26 patients (74.3%) had stage Ⅲ/Ⅳ disease, 6 (17.1%) had bone marrow involvement, and 11 (31.4%) had IPI 3-5.By July 2023, 3 subjects did not return to the hospital for further treatment after the first cycle. 32 subjects received Chi+AZ-CHOP regimen treatments at least 2 cycles,median treatment cycles were 4 cycles. 2 subjects progressed during the treatment, 10 subjects were performed with autologous hematopoietic stem cell transplantation. The ORR was 87.5% with CR at 46.9%(n=32) .The assessment after autologous hematopoietic stem cell transplantation(n=10), ORR was 100 % and CR was 90%.To date, Evaluation of outcomes in patients with AITL at the end of induction(n=17), ORR was 94.1% and CR was 52.9%. Treatment was generally well tolerated with expected side exects.The most common grade 3-4 hematologic adverse events were neutropenia（45%），febrile neutropenia (40%)，anemia (25%) and thrombocytopenia (15%) ,Grade 3-4 non-hematologic toxicities included hypokalemia（35%）,nausea(30%), vomiting (20%),fatigue (30%),and elevated ALT (4.8%).No treatment-related deaths have been studied so far. C onclusion: This trail proved that chidamide combined with azacytidine +CHOP is feasible and safe in the treatment of peripheral T-cell lymphoma. Especially，achieved a high CR rate in the induction therapy phase of AITL subtype. Although neutropenia is the most common adverse reaction, it is generally safe and controllable.

Impact of Mogamulizumab-Containing Chemotherapy on HBV Reactivation in Patients with T-Cell Lymphoma: A Multicenter Retrospective Observational Study (PROACTIVE-MOGA)

INTRODUCTION Reactivation of hepatitis B virus (HBV) infection is a potentially lethal complication, but may be preventable in patients with chronic HBV infection or resolved HBV infection who receive systemic chemotherapy.The risk of HBV reactivation (HBVR) depends on not only HBV infectious status but also type of systemic chemotherapy. An anti-CCR4 antibody, mogamulizumab (Moga), has been developed for the treatment of peripheral T-cell lymphomas. Moga is known to suppress CCR4-positive regulatory T cells and helper T cells, which can lead to immunological dysfunction. However, there is little evidence regarding the risk of HBVR in patients with chronic HBV infection or resolved HBV infection who receive Moga-containing systemic chemotherapy. We conducted a retrospective observational study to evaluate the risk of HBVR and clinical outcome in those patients. METHODS & MATERIALS: Patients treated with Moga-containing chemotherapy for T-cell lymphoma between May 2012 and March 2021, who were chronic HBV infection (defined as seropositive for HBsAg) or resolved HBV infection (defined as seronegative for HBsAg, but seropositive for anti-HBc or anti-HBs), were included. The primary endpoint was the rate of HBVR; HBVR in HBsAg-positive patients was defined as any of the following three criteria: 1) 2 log or more increase in HBV DNA from baseline, 2) 3.0 Log IU/ml or more of HBV DNA in patients with undetectable HBV DNA at baseline, 3) 4.0 Log IU/ml or more of HBV DNA in patients not available for HBV DNA at baseline. HBVR in HBsAg-negative patients was defined as any of following three criteria: 1) detectable for HBV DNA in patients with undetectable HBV DNA at baseline, 2) 1.3 Log IU/mL or more of HBV DNA in patients not available for HBV DNA at baseline, 3) seroconversion of HBsAg. RESULTS: A total of 23 HBsAg-positive patients and 246 resolved HBV-infected patients were retrospectively reviewed. Among the 23 HBsAg-positive patients, the median age was 65 years (interquartile range [IQR], 63-73) and 19 patients (82%) had adult T-cell leukemia-lymphoma (ATL). Baseline HBV DNA was undetectable level, detectable not quantifiable, and detectable in 9 (39%), 2 (9%), and 12 (52%) patients, respectively. All 23 HBsAg-positive patients received anti-HBV prophylaxis prior to Moga treatment. One of 23 (4.3%) patients experienced HBVR who led to HBV-related hepatitis. Among the 241 patients with resolved HBV infection, the median age was 65 years (IQR, 63-73) and 223 patients (91%) had ATL. Baseline serostatus of anti-HBc and anti-HBs were as follows: anti-HBc positive and anti-HBs positive in 177 patients (72%), anti-HBc-positive but anti-HBs negative in 50 (20%), the remaining 9 were anti-HBc negative but anti-HBs positive. Baseline HBV DNA was undetectable in 233 (95%), detectable not quantifiable in 5 (2%), and the remaining 3 were detectable for HBV DNA. Only 3 patients received anti-HBV prophylaxis. HBVR occurred in 11 patients, and the 2-year cumulative HBVR rate was 3.5% (95% CI, 1.6-16.5). Among the 11 patients with HBVR, the median peak HBV DNA level was 2.1 Log IU/mL (IQR, 1.7-5.0), the median time from first dose of Moga to HBVR was 140 days (IQR, 82-765) and 2 had HBV-related hepatitis. CONCLUSION: Our current study showed that the risk of HBVR was 4.3% (1 of 23) among HBsAg-positive patients with antiviral prophylaxis and 4.6% (11 of 238) among resolved HBV-infected patients without antiviral prophylaxis following Moga-containing chemotherapy. Anti-HBV prophylaxis and HBV DNA monitoring guided preemptive anti-HBV therapy are recommended to prevent HBV-related hepatitis for HBsAg-positive and resolve HBV-infected patients, respectively.

Genome-Wide CRISPR Screen Identifies MAD2L1BP, ANAPC15 and SLC39A7 As Intrinsic Regulators for Brentuximab Vedotin Sensitivity in Peripheral T-Cell Lymphoma Cells

Introduction: Brentuximab Vedotin (BV), an antibody-drug conjugate that specifically delivers the potent cytotoxic drug monomethyl auristatin E (MMAE) to CD30-positive cells, has been widely used as one of the key drugs for the treatment of peripheral T-cell lymphomas (PTCLs). BV shows relatively high response rate, however, the prognosis of PTCLs is not still satisfactory. The molecular mechanisms concerning sensitivity to BV remain to be clarified. Methods: To assess the cell-intrinsic genes affecting susceptibility to BV in PTCL cells, we performed a whole-genome loss-of-function CRISPR screen in DEL, an anaplastic large cell lymphoma (ALCL), ALK-positive cell line. DEL cells were transduced with the Brunello CRISPR knockout pooled library targeting 19,114 genes (4 sgRNAs/gene) followed by puromycin selection. Then, the transduced cells were treated with BV or DMSO control for 6 days. To rank the sgRNAs responsible for BV sensitivity, MAGeCK algorithm was used. Among the top 20 enriched genes, we further selected ones having at least 2 sgRNAs with a log2 fold change (BV/DMSO) < -0.5 or >0.5 as genes whose knock out confer BV sensitivity or resistance, respectively. Results: Through the whole-genome loss-of-function CRISPR screen, we identified 17 genes or 15 genes whose knock out confer BV sensitivity or resistance, respectively. TNF receptor superfamily member 8 (TNFRSF8, also known as CD30), a known BV target, was ranked as a top gene for BV resistance, confirming the reliability of our screening. Among the 17 enriched genes whose knock out confer BV sensitivity, endogenous mitotic checkpoint complex (MCC) inhibitors, namely MAD2L1BP and ANAPC15 were identified. As a confirmation, we knocked out MAD2L1BP or ANAPC15 in PTCL cell lines by CRISPR and found the enhanced susceptibility to BV of the cells. MAD2L1BP and ANAPC15, the endogenous MCC inhibitors, are known to facilitate anaphase-promoting complex/cyclosome (APC/C) activation. Therefore, we evaluated whether APC/C inhibition sensitize the PTCL cells to BV or not. Importantly, a combination use of proTAME, an APC/C inhibitor, and BV significantly suppressed cell proliferation of multiple PTCL lines, including ALCL, ALK-positive and adult T-cell leukemia/lymphoma (ATLL) (Fig. 1), compared to each single agent. In cell cycle analyses, PTCL lines treated with the combination demonstrated increased percentages of cells in G2/M phase, compared to each single agent. On the other hand, we found SLC39A7, a zinc channel in endoplasmic reticulum (ER), among 15 enriched genes whose knock out confer BV resistance. Since SLC39A7 has been reported to regulate TNFR1 cell surface expression (Fauster et al. Cell Death & Differentiation 2019), we hypothesized SLC39A7 could also affect the CD30 cell surface expression levels. In fact, flow cytometry analyses revealed downmodulation of CD30 cell surface expression in SLC39A7 knocked out PTCL lines (Fig. 2). We further evaluated the amount of CD30 protein expression by immunoblotting and found that SLC39A7 knocked out cells reduced the amount of mature form of CD30, which was consistent with the findings in flow cytometry. Intriguingly, we observed increasement of lower molecular weight band, which was considered as immature precursor CD30, in SLC39A7 knocked out cells, suggesting that impared glycobiology in ER might be a cause for surface CD30 downregulation in SLC39A7 knocked out PTCL cells. Finally, we treated PTCL lines with NVS-ZP7-4, an SLC39A7 inhibitor and the similar results were obtained regarding to CD30 expression by flow cytometry and immunoblotting. Conclusions: We performed an unbiased genome-wide CRISPR/Cas9 library screen and identified cell-intrinsic regulators for BV sensitivity in PTCLs. Our screening results suggested that the disruption of MAD2L1BP/ANAPC15 or APC/C inhibition would be a potential strategy to enhance therapeutic activity of BV in PTCLs. We also identified SLC39A7 downregulation could confer BV resistance by downregulating CD30 cell surface expression.

Genome-Wide CRISPR Screen Identifies ZNF451 Regulating Sensitivity to Topoisomerase 2 Inhibitors in Peripheral T-Cell Lymphoma Cells

Introduction: Despite the recent therapeutic developments for peripheral T-cell lymphomas (PTCLs), their prognosis remains dismal. Topoisomerase 2 inhibitors (TOP2i), which increase the amount of TOP2-DNA covalent complex and block DNA double-strand break repair, have long been used as key drugs in the treatment of PTCLs. The molecular mechanisms underlying sensitivity to TOP2i remain to be fully elucidated. Methods: To elucidate the cell-intrinsic genes affecting TOP2i sensitivity in PTCL cells, we performed whole-genome loss-of-function CRISPR screenings in adult T-cell leukemia/lymphoma (ATLL) cell lines. ST1 and KK1 cells were transduced with the Brunello CRISPR knockout pooled library targeting 19,114 genes (4 sgRNAs/gene) followed by puromycin selection. The transduced cells were then treated with etoposide (ETP), doxorubicin (DOX) or DMSO control for 8 days. The MAGeCK algorithm was used to rank the sgRNAs responsible for TOP2i sensitivity. Among the top 500 enriched genes, we further selected the those with at least 2 sgRNAs with a log2 fold change (TOP2i/DMSO) < -0.5 or >0.5 in both ST1 and KK1 cells as genes whose knockout conferred TOP2i sensitivity or resistance, respectively. Results: Using the whole genome loss-of-function CRISPR screen, we identified 3 genes and 2 genes whose knockout conferred ETP sensitivity and resistance, respectively. TOP2A, a known ETP target, was ranked as a top gene for ETP resistance, confirming the reliability of our screenings (Fig. 1). In the same way we also extracted 3 genes whose knockout conferred DOX sensitivity. Interestingly, zinc finger protein 451 (ZNF451) was identified as an overlapping gene whose knockout conferred sensitivity in both screens for ETP and DOX. ZNF451 is an E3 SUMO ligase and was previously reported to be an endogenous DNA repair factor for TOP2i-induced DNA double-strand breaks (Schellenberg et al. Science 2017). The role of ZNF451 in PTCL cells has not been previously reported, prompting us to focus on ZNF451 in further analyses. For a confirmatory experiments, we transduced sgRNAs targeting ZNF451 (sgZNF451) in ATLL cell lines. To see the knockout efficiencies of the sgZNF451, we performed immunoblot analysis by using anti-ZNF451 antibody and found three bands with different levels of reduction. To ensure whether the bands detected by the anti-ZNF451 antibody represented endogenous ZNF451 protein, we engineered the ATLL cell line with an HA-tag at the 5' UTR of the endogenous ZNF451 gene locus by CRISPR-mediated knock-in. Immunoblot analysis of sgZNF451-transduced engineered cells expressing HA-tag-ZNF451 by using anti-HA antibody showed almost the same pattern of the bands as shown in the blot by anti-ZNF451 antibody. Thus, we confirmed that sgZNF451 worked efficiently and concluded that post-transcriptional modification affected the stability of ZNF451 protein in ATLL cells. Next, we investigated the role of ZNF451 on cell viability. While sgZNF451-transduced ATLL cells did not differ from control sgRNA-transduced cells in terms of cellular proliferation under normal culture conditions, sgZNF451-transduced ATLL cells showed increased sensitivity to both ETP and DOX compared to control cells with statistical significance, confirming our screening results (Fig. 2). Importantly, sgZNF451-mediated sensitization to ETP and DOX was found not only in ATLL cells but also in other PTCL cell lines including ALK-positive and ALK-negative anaplastic large cell lymphoma (ALCL). Mechanistically, apoptosis and G2/M cell cycle arrest were induced at significantly higher frequencies by ETP treatment in ZNF451 knocked out cells compared to control cells. Given the role of ZNF451 in TOP2i sensitivity in PTCL cells, we investigated whether ZNF451 expression levels stratify the prognosis of PTCL patients treated with CHOP-like regimens. To test this, FFPE samples from 45 PTCL-NOS patients were used for Q-PCR analysis of ZNF451 mRNA but we did not find any correlation between the ZNF451 expression and prognosis. Conclusions: We performed unbiased genome-wide CRISPR/Cas9 library screens and identified ZNF451 as an important regulator of sensitivity to TOP2i in PTCL cells. Further studies are needed to determine whether measuring ZNF451 protein levels can be used as a biomarker in PTCL patients who are treated with TOP2i.

Development and Characterization of a Novel Murine Peripheral T-Cell Lymphoma Cell Line Which Closely Mimics Human Disease

Peripheral T-cell lymphoma (PTCL) represents a heterogenous group of aggressive non-Hodgkin lymphomas with poor prognostic outcomes and limited treatment options. Despite the advances in genomic sequencing and molecular characterization, the complex and elusive nature of PTCL's underlying biology has proven difficult to fully understand and manage effectively. The development and refinement of therapeutic strategies for PTCL are impeded by a paucity of reliable preclinical models that accurately mimic the disease's pathophysiology. There is a dire need for more physiologically relevant models for PTCL. Improved models allow for a better understanding of the disease's molecular and cellular mechanisms, facilitate the development of innovative therapeutic strategies, and ultimately improve patient outcomes. Here we described a new T-cell lymphoma cell line (LM-23) derived from a 12-week-old female Balb/cJ mouse which developed diffuse adenopathy and splenomegaly. Tumors from this mouse were cultured in cRPMI + 10% fetal bovine serum for 4 weeks without supplementation of additional cytokines and passaged 3-4 times per week where we found the cells to be non-adherent. Immunophenotyping of LM-23 demonstrated positivity for CD90, CD3, TCR-beta, CD4(partial/subset), CD8, PD1 (positive), ICOS (positive) and negative for B-cell and myeloid lineage markers (Fig. 1B). This immunophenotype most closely resembles PTCL-NOS in humans at an immunophenotypic characterization level. Whole exome sequencing is in progress and will be presented. Intravenous administration of this cell line to syngeneic Balb/cJ mice resulted in rapid establishment of diffuse adenopathy, splenomegaly, and liver metastases. Bulky adenopathy was observable within 14 days of administration. Histologically, these tumors consisted of sheets of medium to large sized lymphocytes with clumped chromatin and prominent nucleoli, similar to human T-cell lymphomas (Fig. 1A). Subcutaneous administration demonstrated rapid tumor growth with mice reaching terminal endpoints (>2,000mm 3) within 21 days following administration. As CHOP-based (cyclophosphamide, doxorubicin, vincristine, and prednisone) therapies are the primary backbone for treatment of PTCL, we tested whether CHOP therapy alone had anti-tumor activity to LM-23. Tumor bearing mice (~150mm 3) were treated with CHOP and monitored for tumor growth. All mice treated were non-responsive to CHOP therapy with no difference in tumor growth compared to untreated mice. Additionally, LM-23 bearing mice treated with anti-PD1 showed signs of hyperprogression, which has been observed in human patients in clinical trials (Gao Y et al. JCI Insight 2023, Bennani NN et al. Blood Supplement 2019). Additional therapeutic target testing is underway and will be presented. In conclusion, the newly established LM-23 T-cell lymphoma cell line provides a novel, physiologically relevant preclinical model for the study of PTCL. Its phenotypic characteristics, rapid growth, and metastatic behavior in syngeneic mice, along with its resistance to CHOP therapy and hyperprogression upon anti-PD1 treatment, mimicking the clinical scenarios observed in some human PTCL patients. These features highlight LM-23's potential as a valuable tool for understanding the biological mechanisms underlying PTCL and for the development and testing of innovative therapeutic strategies. We hope that the LM-23 cell line will contribute significantly to these efforts, ultimately improving outcomes for patients afflicted with PTCL.

The combination of brentuximab vedotin and chidamide synergistically suppresses the proliferation of T-cell lymphoma cells through the enhancement of apoptosis

PurposePeripheral T-cell lymphoma (PTCL) is an aggressive disease with a poor prognosis. Brentuximab vedotin (BV), an anti-CD30 monoclonal antibody linked to a microtubule-disrupting agent, has been approved for the treatment of PTCL. We evaluated a new effective combination partner of BV using non-clinical approaches that could potentially identify agents capable of improving survival times for patients with PTCL.MethodsA high-throughput screening test was used to select the most synergistic partner of BV from 14 candidate drugs that were under development or available in clinical practice for PTCL. HH cells, originating from an aggressive cutaneous T-cell lymphoma, were used as an experimental model of PTCL. Apoptotic effects of the synergistic partner of BV were further investigated in vitro and in vivo using HH-cell xenograft mice.ResultsChidamide (tucidinostat), a novel histone deacetylase inhibitor, was found to have the greatest synergistic effect with BV on HH cells. The combined effects of chidamide and BV were demonstrated in a study of HH-cell xenograft mice; mean tumor size following combined treatment was 22% of that observed in the control group, compared with 71% and 58% following chidamide and BV monotherapy, respectively. Further investigations in vitro and in vivo revealed that the levels of an anti-apoptotic protein, Bcl-2, and a rate-limiting factor of DNA replication, CDC45, were reduced in HH cells treated with chidamide combined with BV compared with the control group.ConclusionThe use of chidamide in conjunction with BV may positively affect and enhance T-cellular apoptotic pathways without offsetting each other.

Chidamide plus prednisone, cyclophosphamide, and thalidomide for relapsed or refractory peripheral T-cell lymphoma: A multicenter phase II trial.

Although the treatment of peripheral T-cell lymphoma (PTCL) has undergone advancements during the past several years, the response rate and long-term effects with respect to patients with PTCL remain unsatisfactory-particularly for relapsed or refractory (R/R) patients. This phase II trial was designed to explore the efficacy and safety of an all-oral regimen of chidamide plus prednisone, cyclophosphamide, and thalidomide (CPCT) for R/R PTCL patients who could not tolerate the standard chemotherapy for a variety of reasons. We conducted a multicenter phase II clinical trial in which we combined chidamide (30 mg twice weekly) with prednisone (20 mg daily after breakfast), cyclophosphamide (50 mg daily after lunch), and thalidomide (100 mg daily at bedtime) (the CPCT regimen) for a total of fewer than 12 cycles as an induction-combined treatment period, and then applied chidamide as single-drug maintenance. Forty-five patients were ultimately enrolled from August 2016 to April 2021 with respect to Chinese patients at nine centers. Our primary objective was to assess the overall response rate (ORR) after the treatment with CPCT. Of the 45 enrolled patients, the optimal ORR and complete response (CR)/CR unconfirmed (CRu) were 71.1% (32/45) and 28.9% (13/45), respectively, and after a median follow-up period of 56 months, the median progression-free survival (PFS) and overall survival (OS) were 8.5 months and 17.2 months, respectively. The five-year PFS and OS rates were 21.2% (95% confidence interval [CI], 7.9-34.5 %) and 43.8% (95% CI, 28.3-59.3 %), respectively. The most common adverse event was neutropenia (20/45, 44.4%), but we observed no treatment-related death. The all-oral CPCT regimen was an effective and safety regimen for R/R PTCL patients who could not tolerate standard chemotherapy for various reasons. ClinicalTrials.gov, NCT02879526.

CLINICAL EFFICACY OF CD34 POSITIVE SELECTION EX‐VIVO PURGING DURING AUTOLOGOUS STEM CELL TRANSPLANTATION IN PERIPHERAL T CELL LYMPHOMA

Background: Autologous stem cell transplantation (ASCT) is the standard treatment for peripheral T-cell lymphomas (PTCLs). Strategies that reduce the relapse rate and treatment-related mortality are essential for successful ASCT. Because in vivo/in vitro purging methods using rituximab are not appropriate for T-cell lymphomas, an ex vivo CD34+ selective purging system using CliniMACS is the most reliable method to reduce autograft tumor cell contamination in these tumors. In the present study, we retrospectively analyzed the clinical outcomes of HDT/ASCT after ex vivo purging via the CD34+ selective method in T-cell NHL patients. Methods: We retrospectively investigated the influence of ex vivo purging with CD34+ selection to maximize the effects of ASCT. Of 67 consecutive PTCL patients, 32 and 35 underwent purged and unpurged ASCT. Results: The purged group had improved overall survival (OS), disease-free survival (DFS), and cumulative incidence of relapse (hazard ratio [HR] = 2.68, p = 0.016; HR = 3.97, p = 0.002; and HR = 3.65, p = 0.004, respectively), compared to the unpurged group. Prognostic factor analysis showed that unpurged ASCT, chromosomal abnormalities at initial diagnosis, high risk, and pre-ASCT disease status were associated with poor survival outcomes. Subgroup analysis demonstrated that purging was most appropriate for International Prognostic Index high-risk patients who underwent upfront ASCT (HR = 3.35 [OS] and = 6.59 [DFS]). In purged ASCT group, NK cell activity and the lymphocyte-to-monocyte ratio known as an independent prognostic factor were increased after ASCT with statistical significance; the lymphocyte-to-monocyte ratio (LMR) was significantly increased after ASCT in the purged group (mean difference = 1.484, 95% CI = 0.407–2.560; p = 0.009). Also, Engraftment was achieved in all patients with no need for unpurged autologous stem cell backup in purged group. There were no engraftment failures or differences in adverse events including of transplant-related viral infections between the two groups. The research was funded by: The research was funded by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2020R1G1A1099654). Keywords: Aggressive T-cell non-Hodgkin lymphoma, Stem Cell Transplant No conflicts of interests pertinent to the abstract.

Synthesis and Preclinical Development of a Promising Novel Romidepsin Nanoparticle for the Treatment of Peripheral T‐Cell Lymphoma (PTCL)

Introduction: The HDAC inhibitors are important drugs for the treatment of PTCL. While these drugs produce ORR of 25–30% with short PFS, responses can last over a year. There is still debate on the optimal ways to use HDAC inhibitors. Most HDAC inhibitors are oral with prolonged AUC of exposure. Romidepsin (R) is administered IV and exhibits a half-life of only 3 hours, though biological effects on chromatin may persist for 24–48 hours. A failed Phase 4 study led to the withdrawal of R for R/R PTCL. In an effort to try and create improved alternatives to R with better efficacy and safety, we deployed a proprietary nanochemistry platform to synthesize NanoRomidepsin (NR) particles, identifying a lead molecule that is comparable to or better than the predecessor R. Methods: Using a combinatorial strategy of solvent screening and polymer chemistry, we developed a first-in-class NR therapeutic with a unique and specific Drug/ Polymer/Surfactant ratio. We utilized dynamic Light Scattering (DLS), cryo-electron microscopy (EM) and liquid chromatography-mass spectrometry (LC-MS) to characterize the size, morphology, and drug encapsulation efficiency of the NR nanoparticles. Cell viability, flow cytometry and western blotting (WB) were performed to determine the effect of NR on cytotoxicity, apoptosis, and histone acetylation across a panel of PTCL cell lines. The maximum tolerated dose of NR was based on an in vivo single-dose and repeated dose toxicity study. Pharmacokinetic studies were performed in mice treated at ½ MTD with quantitation of plasma drug levels by LC-MS. Results: Cryo-EM and DLS confirmed that NR had a poly-dispersity index (PDI) between 0.16 to 0.27 and a z-average of 60–70 nm, indicating uniform size and homogenous particle distribution in the desired ranges. The cell viability assays demonstrated that R and NR produced comparable cytotoxicity (IC50 in range of 0.7–1.9 nM). Flow cytometry and WB analysis demonstrated that NR induced apoptosis and increased acetylation of H3/H4 in a time and concentration-dependent manner. In vivo single-dose and repeated dose toxicity assays revealed a clear correlation between dose and weight loss and/or clinical score in both R and NR treated groups. Pharmacokinetic analyses revealed a substantially greater AUC for NR, which was 3- and 25-fold higher compared to R for IP and IV routes of administration respectively. Interestingly, the markedly greater AUC for NR did not appear to be associated with increased in vivo toxicity. Conclusions: We have synthesized a lead nanotherapeutic of R that will be translated to the clinic. In keeping with other nanotherapeutic drugs, nanosizing drugs tend to increase their volume of distribution (Vd), AUC and markedly improve their tolerability. Large scale in vivo modeling of NR is underway. Data on the development and differentiation of our lead NR asset will be presented, as will the strategy for clinical development. The research was funded by: IVY grant, Translational Orphan Blood Cancer Research Initiative Fund Keyword: Molecular Targeted Therapies No conflicts of interests pertinent to the abstract.

New pharmacotherapeutic approaches for the treatment of peripheral T-cell lymphoma

Today, it is difficult to overestimate the new directions in the pharmacotherapy of peripheral T-cell lymphomas (PTCL): immunotherapy, including adoptive, targeted therapy and chemotherapy. However, there are few biomarkers that predict response to therapy. A big problem is patients with refractory and recurrent PTCL who do not respond to such therapy or demonstrate adverse events, which makes it important to personalize therapy and search for predictive markers, followed by thorough analytical and clinical validation. The literature highlights the importance of using biomarkers obtained from whole exome sequencing and tumor transcriptome sequencing. Thе review discusses the T cell ontogenesis, as well as the possibilities of personalization of anticancer drugs such as azacitidine, duvelisib, romidepsin, and bortezomib for the treatment of refractory or recurrent PTCL.

First-Line Therapy for Nodal T-cell Non-Hodgkin Lymphomas: an Unmet Need in Hematology.

The main aim of this review is to summarize first-line therapy of nodal T-cell non-Hodgkin lymphoma. Current treatment with CHOP chemotherapy results in poor outcomes in the majority of patients. However, there are advances within the field. First breakthrough is the ECHELON-2 trial which showed that the addition of brentuximab vedotin improves outcomes in anaplastic large cell lymphoma. However, other types of peripheral T-cell non-Hodgkin lymphoma were underrepresented with optimal treatment not known. Second breakthrough is an increase of autologous stem cell transplantation usage in the first complete metabolic remission, except in ALK + anaplastic large cell lymphoma, offering better disease control. Despite advances in the field, CHOP remains the standard treatment for the majority of these lymphomas, but multiple trials are underway with the aim to improve this unmet need in hematology and, hopefully, leading us to a new era in the treatment of peripheral T-cell lymphomas.