Adult T-cell Leukemia/lymphoma Patients Research Articles

Clinical significance of NOTCH1 and FBXW7 alterations in adult T-cell leukemia/lymphoma.

Here, we investigated the clinical significance of NOTCH1 and FBXW7 alterations for adult T-cell leukemia/lymphoma (ATLL) treatment outcomes. NOTCH1 alterations were identified in 37 (14.4%) of 257 patients, of which 33 were single nucleotide variants/insertion-deletions in the PEST domain, and 7 were in the heterodimerization or LIN-12/Notch repeats domains. FBXW7 alterations were observed in nine ATLL patients (3.5%). For patients without allogeneic hematopoietic stem cell transplantation (HSCT), NOTCH1, but not FBXW7, alterations were significantly and independently associated with worse overall survival (median OS 0.5years, 95% confidence interval [CI] 0.4-0.5years for 27 patients with NOTCH1 alterations vs 1.8years, 95% CI 1.3-2.2years for 170 patients without). Also, for patients receiving mogamulizumab, but not allogeneic-HSCT, NOTCH1, but not FBXW7, alterations were significantly associated with worse survival (median survival from the first dose of mogamulizumab 0.4years, 95% CI 0.3-0.5years for 12 patients with NOTCH1 alterations vs 1.4years, 95% CI 0.9-2.0years for 87 without). In contrast, NOTCH1 alterations had no significant impact on survival of patients who did receive allogeneic-HSCT. Thus, mogamulizumab-containing treatment was unable to overcome treatment refractoriness of ATLL with NOTCH1 alterations. Therefore, patients with NOTCH1 alterations are recommended for allogeneic-HSCT.

Allogeneic transplantation for adult T-cell leukemia/lymphoma in adolescent and young adults and young patients: A nationwide retrospective study by the ATL working group of the Japan society for transplantation and cellular therapy.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) provides durable remission for patients with adult T-cell leukemia/lymphoma (ATL); however, few studies have focused on post-transplant outcomes in ATL patients ≤49years. To clarify prognostic factors in ATL among patients <40years (adolescents and young adult [AYA]; n=73) and 40-49years (Young; n=330), we conducted a nationwide retrospective study. Estimated 3-year overall survival (OS) rates were 61.8% and 43.1% in AYA and Young patients, respectively (p=0.005). In the multivariate analysis, Young patients showed worse OS (Hazard ratio (HR) [95% confidential interval] 1.62 [1.10-2.39], p=0.015), chronic graft-versus-host disease (GVHD)-free and relapse-free survival (CRFS) (HR 1.54 [1.10-2.14], p=0.011), and GVHD-free and relapse-free survival (GRFS) (HR 1.40 [1.04-1.88], p=0.026) than AYA patients. No significant differences were observed in OS, CRFS, or GRFS between the myeloablative conditioning (MAC) and reduced-intensity conditioning (RIC) regimens; however, non-relapse mortality was significantly lower in patients with the RIC regimen than those with the MAC regimen (HR 0.46 [0.24-0.86], p=0.015). In summary, OS was worse in Young patients than in AYA patients in the allo-HSCT setting for ATL. Furthermore, the RIC regimen has potential as an alternative treatment option for ATL patients ≤49years.

Succinic semialdehyde derived from the gut microbiota can promote the proliferation of adult T-cell leukemia/lymphoma cells

Adult T-cell leukemia/lymphoma (ATLL) is a refractory blood cancer with severe immunodeficiency resulting from retroviral infection. ATLL develops in only 5 % of HTLV-1-infected individuals, but the entire mechanism of ATLL progression remains unknown. Since recent studies have reported that the gut microbiome influences the progression of various diseases, we hypothesized that ATLL is also related to the gut microbiome and aimed to investigate this relationship.We analyzed the taxonomic and functional profiles of the gut microbiota of ATLL patients (n = 28) and HTLV-1-infected individuals (n = 37). We found that the succinic semialdehyde (SSA) synthesis pathway was significantly enriched in the gut microbiome of ATLL patients (P = 0.000682), and Klebsiella, whose abundance was significantly greater in ATLL patients and high-risk HTLV-1-infected individuals (P = 0.0326), was the main contributor to this pathway. Administration of SSAs to ATLL cell lines resulted in significant cell proliferation.Herein, we propose that the gut microbiome can regulate ATLL progression via metabolites.

Long-Term Survival of Patients with Adult T-Cell Leukemia/Lymphoma Treated with Amplified Natural Killer Cell Therapy

Background: Adult T-cell leukemia/lymphoma (ATL) is caused by human T-cell leukemia virus type 1 (HTLV-1) after a long latent infection. HTLV-1 induces the indolent or aggressive type of leukemia in 5% of HTLV-1 carriers. ATL, especially the aggressive type, is resistant to multi-agent chemotherapy. The indolent type often progresses to the aggressive type. Even in the most indolent-type cases, that is, smoldering ATL, the average survival time is 55.0 months. Case Presentation: Five patients with ATL were followed up for their clinical course after amplified natural killer cell (ANK) therapy. Four patients who received ANK therapy as first-line therapy achieved complete remission and showed long-term survival without aggressive conversion or relapse for more than 5 years. One patient was treated with multiagent chemotherapy due to acute exacerbation but relapsed 2 months later. She was subsequently treated with radiation and ANK therapy and survived for more than 6 years. Furthermore, ANK therapy enhanced the immune function of ATL patients to a level higher than that of normal individuals. Conclusions: ANK therapy has great potential as first-line treatment for ATL.

Distinctive genomic features of human T-lymphotropic virus type 1-related adult T-cell leukemia-lymphoma in Western populations.

Adult T-cell leukemia-lymphoma (ATLL) is an aggressive Human T-cell Leukemia Virus Type 1 (HTLV-1)-driven malignancy. Although Western hemisphere (Afro-Caribbean and South American) patients face worse prognoses, our understanding of ATLL molecular drivers derives mostly from Japanese studies. We performed multi-omic analyses to elucidate the genomic landscape of ATLL in Western cohorts. Recurrent deletion and/or damaging mutations involving FOXO3, ANKRD11, DGKZ, and PTPN6 implicate these genes as potential tumor suppressors. RNA-seq, published functional data and in vitro assays support the roles of ANKRD11 and FOXO3 as regulators of T-cell proliferation and apoptosis in ATLL, respectively. Survival data suggest ANKRD11 mutation may confer a worse prognosis. Japanese and Western cohorts, in addition to acute and lymphomatous subtypes, demonstrated distinct molecular patterns. GATA3 deletion was associated with unfavorable chronic cases. IRF4 and CARD11 mutations frequently emerged in relapses after interferon therapy. Our findings reveal novel putative ATLL driver genes and clinically relevant differences between Japanese and Western ATLL patients.

Leukemia-Related Signaling Pathways Among HTLV-1-Derived Adult T Cell Leukemia/Lymphoma and Asymptomatic Carriers in Comparison to Normal Group.

Human T cell lymphotropic virus type 1 (HTLV-1) is associated with adult T cell leukemia/lymphoma (ATLL), a fetal malignant infection. Recently, HTLV-1 new asymptomatic carriers (ACs) have frequently been reported among blood donors. Reaching the profound concept of HTLV-1-associated molecular pathogenesis could result in finding novel therapeutic strategies. The current study aimed to determine leukemia-related signaling regulation in ATLL. Thirty participants were evaluated in 3 groups, including 10 ATLL patients, 10 ACs, and 10 normal controls. Blood samples were isolated without any chemotherapy history from ATLL patients. Also, blood samples were recovered from ACs and normal individuals. White blood cells isolation was done on the collected blood samples. After this, RNA was extracted from the prepared samples and used for the cDNA synthesis. TAX and HTLV-1 basic leucine zipper factor as viral genes and cellular genes, including MKP-1, EVI-1, JNK-1, FOXO-1, AKT-1, DEPTOR, MTOR, and JUN, were investigated using real-time PCR. The mean age of ATLL patients was 53.2 ± 7.32 years, and 9 (90%) were male. The EVI-1 and FOXO-1 expression levels were significantly associated with ATLL patients compared with the internal control. However, the significant differences in expression of other genes in the remaining groups were not seen. Discovering viral and cellular signaling pathways that regulate HTLV-1 transformation is essential. A novel therapeutic strategy for ATLL-regulating cellular signaling pathways invivo could be considered. Therefore, clinical trials using activators and inhibitors of related cellular signaling pathways for cell therapy of ATLL are recommended. It is recommended that more investigation be conducted on FOXO-1 and EVI-1 to target these genes and reveal the molecular pathogenesis of ATLL.

Individual HLAs affect survival after allogeneic stem cell transplantation in adult T-cell leukaemia/lymphoma.

Allogeneic haematopoietic stem cell transplantation (allo-HSCT) is the only curative therapy for adult T-cell leukaemia/lymphoma (ATL). Specific HLAs are associated with outcomes of immunotherapy and allo-HSCT. We hypothesised that individual HLAs would affect the clinical outcomes of ATL patients after allo-HSCT. Using data from a Japanese registry, we retrospectively analysed 829 patients with ATL who received transplants from HLA-identical sibling donors or HLA-A, -B, -C or -DRB1 allele-matched unrelated donors between 1996 and 2015. We evaluated the overall mortality risk of HLA-A, -B and -DR antigens with frequencies exceeding 3%. Outcomes were compared between transplants with or without specific HLA antigens. Of the 25 HLAs, two candidates were identified but showed no statistically significant differences by multiple comparison. HLA-B62 was associated with a lower risk of mortality (hazard ratio [HR], 0.68; 95% confidence interval [CI]: 0.51-0.90; p = 0.008), whereas HLA-B60 was associated with a higher risk of mortality (HR, 1.64; 95% CI: 1.19-2.27; p = 0.003). In addition, HLA-B62 was associated with a lower risk of transplant-related mortality (TRM) (HR, 0.52; 95% CI: 0.32-0.85, p = 0.009), whereas HLA-B60 was associated with a higher risk of grades III-IV acute graft-versus-host disease (HR, 2.63; 95% CI: 1.62-4.27; p < 0.001). Neither HLA influenced relapse. The higher risk of acute GVHD in HLA-B60-positive patients and the lower risk of TRM in HLA-B62-positive patients were consistent with previously obtained results from patients with other haematological malignancies. Consideration of HLA in ATL patients may help to predict risk and outcomes after allo-HSCT.

Abstract 3965: A cytolytic effector CD8+ T cell response is associated with remission in adult T-cell leukemia/lymphoma

Abstract Introduction: Adult T-cell leukemia/lymphoma (ATLL) is a rare blood cancer that develops in 3-5% of human T-lymphotropic virus-1 (HTLV1) carriers when the combination of viral oncoproteins and somatic mutations lead to malignant transformation of HTLV1 infected CD4+ T cells. ATLL has the worst overall survival among peripheral T cell lymphomas and remains a fatal disease despite efforts to improve outcomes over the last 35 years. First-line combination chemotherapy rarely achieves a durable response and two immune-modulating treatments (α-CCR4 and α-PD-1 monoclonal antibodies) failed in clinical trials. These findings highlight an urgent need to improve our understanding of the functional state of host immunity in ATLL patients. A host immune response against HTLV1 is pivotal in preventing ATLL development. Malignant ATLL cells can escape immune surveillance by preventing antigen presentation and engaging immune checkpoints. The prospect of an ATLL clone inducing systemic suppression was suggested in the literature but has not been directly examined. Furthermore, HTLV1-specific CD8+ cytotoxic T lymphocytes (CTLs) play an important role during viral latency, yet it remains unknown if they play a clinically relevant role during ATLL treatment. Methodology: In this work, we hypothesized that malignant ATLL cells will exhibit a suppressive immune phenotype and that effective therapeutic interventions will augment anti-ATLL CTLs to promote durable remission. We implemented an immune profiling approach to analyze PBMC samples from ATLL patients. Specifically, we developed a powerful 30-marker spectral flow panel to discriminate malignant ATLL cells from non-transformed lymphocytes (T, B, and NK cells) and monitor the expression of key transcription factors and markers associated with proliferation, cytolysis, and exhaustion. We analyzed diagnostic samples from the Montefiore-Einstein ATLL Biobank and samples collected during a phase 2 clinical trial aimed to assess the efficacy of a promising Belinostat/Zidovudine/Interferon-α combination therapy against ATLL (NCT02737046). Results: Our findings reveal that malignant ATLL cells exhibit an immune phenotype associated with robust immunosuppression and yet distinct from other suppressive immune cells (i.e., regulatory T cells). Additionally, we discovered that ATLL patient samples contained a unique population of phenotypically exhausted CD8+ T cells, the proportion of which was drastically reduced in patients under remission. Remarkably, a decrease in this exhausted subset correlated with the expansion of highly cytolytic CD8+ CTLs. Conclusion: Altogether, our findings suggest that ATLL cells may drive CD8+ CTLs into exhaustion to achieve immune evasion and that a robust anti-ATLL CTL response actively contributes to a remission state. Citation Format: Erik Guillen, Eric Liu, Yanhua Wang, Aditi Shastri, Alejandro Sica, Amit Verma, Xingxing Zhang, Juan Carlos Ramos, Hilda Ye, Gregoire Lauvau. A cytolytic effector CD8+ T cell response is associated with remission in adult T-cell leukemia/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 3965.

Development of Innate-Immune-Cell-Based Immunotherapy for Adult T-Cell Leukemia-Lymphoma.

γδ T cells and natural killer (NK) cells have attracted much attention as promising effector cell subsets for adoptive transfer for use in the treatment of malignant and infectious diseases, because they exhibit potent cytotoxic activity against a variety of malignant tumors, as well as virus-infected cells, in a major histocompatibility complex (MHC)-unrestricted manner. In addition, γδ T cells and NK cells express a high level of CD16, a receptor required for antibody-dependent cellular cytotoxicity. Adult T-cell leukemia-lymphoma (ATL) is caused by human T-lymphotropic virus type I (HTLV-1) and is characterized by the proliferation of malignant peripheral CD4+ T cells. Although several treatments, such as chemotherapy, monoclonal antibodies, and allogeneic hematopoietic stem cell transplantation, are currently available, their efficacy is limited. In order to develop alternative therapeutic modalities, we considered the possibility of infusion therapy harnessing γδ T cells and NK cells expanded using a novel nitrogen-containing bisphosphonate prodrug (PTA) and interleukin (IL)-2/IL-18, and we examined the efficacy of the cell-based therapy for ATL in vitro. Peripheral blood samples were collected from 55 patients with ATL and peripheral blood mononuclear cells (PBMCs) were stimulated with PTA and IL-2/IL-18 for 11 days to expand γδ T cells and NK cells. To expand NK cells alone, CD3+ T-cell-depleted PBMCs were cultured with IL-2/IL-18 for 10 days. Subsequently, the expanded cells were examined for cytotoxicity against ATL cell lines in vitro. The proportion of γδ T cells in PBMCs was markedly low in elderly ATL patients. The median expansion rate of the γδ T cells was 1998-fold, and it was 12-fold for the NK cells, indicating that γδ T cells derived from ATL patients were efficiently expanded ex vivo, irrespective of aging and HTLV-1 infection status. Anti-CCR4 antibodies enhanced the cytotoxic activity of the γδ T cells and NK cells against HTLV-1-infected CCR4-expressing CD4+ T cells in an antibody concentration-dependent manner. Taken together, the adoptive transfer of γδ T cells and NK cells expanded with PTA/IL-2/IL-18 is a promising alternative therapy for ATL.

Molecular pathogenesis of adult T-cell leukemia/lymphoma

Adult T-cell leukemia/lymphoma (ATLL) is an aggressive peripheral T-cell malignancy caused by human T-cell leukemia virus type-1 (HTLV-1) infection. Genetic alterations are thought to contribute to the pathogenesis of ATLL alongside HTLV-1 products such as Tax and HBZ. Several large-scale genetic analyses have delineated the entire landscape of somatic alterations in ATLL, which is characterized by frequent alterations in T-cell receptor/NF-κB pathways and immune-related molecules. Notably, up to one-fourth of ATLL patients harbor structural variations disrupting the 3'-UTR of the PD-L1 gene, which facilitate escape of tumor cells from anti-tumor immunity. Among these alterations, PRKCB and IRF4 mutations, PD-L1 amplification, and CDKN2A deletion are associated with poor prognosis in ATLL. More recently, several single-cell transcriptome and immune repertoire analyses have revealed phenotypic features of premalignant cells and tumor heterogeneity as well as virus- and tumor-related changes of the non-malignant hematopoietic pool in ATLL. Here we summarize the current understanding of the molecular pathogenesis of ATLL, focusing on recent progress made by genetic, epigenetic, and single-cell analyses. These findings not only provide a deeper understanding of the molecular pathobiology of ATLL, but also have significant implications for diagnostic and therapeutic strategies.

Whole-genome CRISPR screening identifies molecular mechanisms of PD-L1 expression in adult T-cell leukemia/lymphoma

AbstractAdult T-cell leukemia/lymphoma (ATLL) is an aggressive T-cell malignancy with a poor prognosis and limited treatment options. Programmed cell death ligand 1(PD-L1) is recognized to be involved in the pathobiology of ATLL. However, what molecules control PD-L1 expression and whether genetic or pharmacological intervention might modify PD-L1 expression in ATLL cells are still unknown. To comprehend the regulatory mechanisms of PD-L1 expression in ATLL cells, we performed unbiased genome-wide clustered regularly interspaced short palindromic repeat (CRISPR) screening in this work. In ATLL cells, we discovered that the neddylation-associated genes NEDD8, NAE1, UBA3, and CUL3 negatively regulated PD-L1 expression, whereas STAT3 positively did so. We verified, in line with the genetic results, that treatment with the JAK1/2 inhibitor ruxolitinib or the neddylation pathway inhibitor pevonedistat resulted in a decrease in PD-L1 expression in ATLL cells or an increase in it, respectively. It is significant that these results held true regardless of whether ATLL cells had the PD-L1 3' structural variant, a known genetic anomaly that promotes PD-L1 overexpression in certain patients with primary ATLL. Pevonedistat alone showed cytotoxicity for ATLL cells, but compared with each single modality, pevonedistat improved the cytotoxic effects of the anti–PD-L1 monoclonal antibody avelumab and chimeric antigen receptor (CAR) T cells targeting PD-L1 in vitro. As a result, our work provided insight into a portion of the complex regulatory mechanisms governing PD-L1 expression in ATLL cells and demonstrated the in vitro preliminary preclinical efficacy of PD-L1–directed immunotherapies by using pevonedistat to upregulate PD-L1 in ATLL cells.

Outcomes of Allogeneic Transplantation for Adult T-Cell Leukemia/Lymphoma in Adolescents and Young Adult (AYA) and Young Patients

Introduction Allogeneic hematopoietic stem cell transplantation (allo-HSCT) provides a durable remission for patients with adult T-cell leukemia/lymphoma (ATL). Reduced-intensity regimens (RIC) have been increasingly used in ATL patients due to their old age and higher non-relapse mortality. However, the role of RIC regimen has not been fully evaluated among ATL patients aged &amp;lt;50 years. We here conducted a nationwide study to evaluate the prognostic impact of conditioning intensity on the post-transplant outcomes in ATL patients aged &amp;lt;50 years. Methods The clinical data of patients aged &amp;lt;50 years who underwent their first allo-HSCT between January 2001 and December 2020 were collected from the Transplant Registry Unified Management Program of the Japan Society for Hematopoietic Cell Transplantation. Cox proportional hazards regression models were used to evaluate variables potentially affecting overall survival (OS), graft-versus-host disease (GVHD)- and relapse-free survival (GRFS), and chronic GVHD-free survival (CRFS). Fine and Gray proportional hazards models were used to evaluate variables potentially affecting cumulative incidences of relapse (CIR) and non-relapse mortality (NRM). CIR and NRM were estimated using cumulative incidence curves to accommodate competing events. A two-sided P-value ≤0.05 was considered to be significant. To examine the effect modification, a threshold for P interaction &amp;lt;0.10 was used to indicate significant differences across prespecified subgroups. Results This study included 73 and 330 patients who were &amp;lt;40 years old (adolescents and young adults [AYA] patients) and 40-49 years old (young patients), respectively. In AYA patients, the median age at HSCT was 36 years (range, 20-39). RIC regimen was used in 16 out of 57 AYA patients (21.9%), and in 74 out of 330 young patients (22.4%) (P=1.000). There was no significant difference of the patient characteristics regarding comorbidity, performance status at HSCT, disease status, clinical subtype, and donor type. The estimated 3-year OS rates were 61.8% and 43.1% in AYA and young patients, respectively (P=0.005); the estimated 3-year CRFS rates were 35.8% and 22.6% in AYA and young patients, respectively (P=0.008); and the estimated 3-year GRFS rates were 26.7% and 15.1% in AYA and young patients, respectively (P=0.006). The estimated 3-year CIR were 36.3% and 39.3% in AYA and young patients, respectively (P=0.407); and the estimated 3-year NRM were 17.0% and 23.4% in AYA and young patients, respectively (P=0.113). In addition, the use of RIC regimen was associated with lower NRM than that of MAC regimen (P=0.015), but there was no significant difference of OS, CRFS, GRFS, and CIR between MAC and RIC regimens. The multivariate analyses revealed that young patients were significantly associated with worse OS (Hazard ratio (HR) [95% confidential interval], 1.62 [1.10-2.39]; P=0.015), CRFS (HR, 1.51 [1.10-2.06]; P=0.010), and GRFS (HR, 1.49 [1.11-1.99]; P=0.008) than AYA patients. The utilization of RIC regimen was significantly associated with lower NRM (HR, 0.46 [0.24-0.86]; P=0.015). To find the optimal selection of conditioning intensity (MAC vs. RIC) by patient's age, we next evaluated the effect modification. In the subgroup analysis, there was significant interaction of conditioning intensity with patient's age (P interaction=0.002) in NRM but not in OS, CRFS, GRFS, and CIR. Among AYA patients, the estimated 1-year NRM were 12.5% and 18.8% in MAC and RIC regimens, respectively (P=0.085). Among young patients, the estimated 1-year NRM were 23.5% and 8.2% in MAC and RIC regimens, respectively (P&amp;lt;0.001). Conclusion The present study clarified that AYA patients exhibited better post-transplant outcomes than young patients, indicating the prognostic value of patient's age in ATL patients aged &amp;lt;50 years. Moreover, no significant differences were observed in OS, CRFS, GRFS, and CIR between RIC and MAC regimens, but the utilization of RIC regimen would reduce the risk of non-relapse death among young patients. These facts suggested that RIC regimen could be an alternative option for ATL patients aged 40-49 years.

Single-Cell RNA Sequencing Revealed the YY1/EZH2/MLH1 Axis As a Possible Therapeutic Target of Intractable Adult T-Cell Leukemia

Background: Due to clinical heterogeneity of adult T-cell leukemia/lymphoma (ATL) and its diverse genetic abnormality, common therapeutic targets of ATL remains unclear. Whereas the YY1/EZH2 axis regulates global epigenetic modification of genes in ATL, its downstream target genes have not been fully elucidated. Meanwhile, DNA mismatch repair proteins may be targeted in ATL. Here we explored underlying molecular axes for ATL progression through comprehensive single-cell RNA-sequencing (sc-RNA-seq). Methods: Peripheral blood of 42 ATL patients and asymptomatic HTLV-1 carriers in addition to two cell lines of ATL43T and ED+ were subjected to the following analyses. Molecular markers associated with their clinical phenotypes were extracted through sc-RNA-seq analysis. Expression levels of DNA mismatch repair proteins (MLH1, MSH2) and target molecules were validated by flow cytometry. Finally, their function was verified through lentiviral shRNA-dependent knockdown and molecular-targeting reagents. Results: While the frequencies of CADM1+ cells among CD4+ T cells were generally correlated with HTLV-1 proviral loads (R = 0.76, p &amp;lt; 0.001), substantial CADM1+ cells were detected but did not increase in some long-remitted cases; thus, CADM1+ cells are biologically heterogeneous. sc-RNA-seq of CADM1+ cells of four ATL cases identified a cluster of CD48-deficient cells. in silico promoter analysis of the cluster extracted a transcription factor YY1 as a candidate for common master regulators. EZH2 and the putative driver genes (CELF2, PTPRC, CBLB, ATXN1, IKZF2) were identified as differentially expressed genes (DEGs) in the cluster. The EZH2-overexpressed cluster was increased in acute-type ATL compared with remitted ATL and smoldering-type ATL. Interestingly, the cluster increased moderately in the other smoldering-type ATL, which required UVB irradiation due to intractable skin lesion. Given that YY1 and EZH2 were up-regulated in acute-type ATL, the cluster may represent tumor aggressiveness. Furthermore, biphasic expression of YY1/EZH2 was observed in 2 acute-type ATL, which indicates that the EZH2 high ATL cells confer malignant signature. In-house analysis on microarray dataset GSE55851 specified the MLH1 associated with YY1/EZH2. MLH1 within CADM1+ fraction was down-regulated in ATL patients with remission (n = 7) but maintained in progressive ATL (n = 6) (p &amp;lt; 0.05). Lentiviral shYY1 knockdown resulted in down-regulation of MLH1 in both ATL43T and ED+ (p &amp;lt; 0.01). The EZH1/2 inhibitor valemetostat down-regulated EZH2 (p = 0.018) and MLH1 (p = 0.014) in primary ATL cells. Finally, knockdown of either YY1 or MLH1 suppressed proliferation of ATL43T and ED+ (p &amp;lt; 0.0001). Conclusions: Our findings indicate that down-regulation of MLH1 through YY1/EZH2 inhibition plays a key role in the treatment of aggressive ATL.

Anti-HTLV-1 immunity combined with proviral load as predictive biomarkers for adult T-cell leukemia-lymphoma.

Human T-cell leukemia virus type 1 (HTLV-1) establishes chronic infection in humans and induces a T-cell malignancy called adult T-cell leukemia-lymphoma (ATL) and several inflammatory diseases such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Persistent HTLV-1 infection is established under the pressure of host immunity, and therefore the immune response against HTLV-1 is thought to reflect the status of the disease it causes. Indeed, it is known that cellular immunity against viral antigens is suppressed in ATL patients compared to HAM/TSP patients. In this study, we show that profiling the humoral immunity to several HTLV-1 antigens, such as Gag, Env, and Tax, and measuring proviral load are useful tools for classifying disease status and predicting disease development. Using targeted sequencing, we found that several carriers whom this profiling method predicted to be at high risk for developing ATL indeed harbored driver mutations of ATL. The clonality of HTLV-1-infected cells in those carriers was still polyclonal; it is consistent with an early stage of leukemogenesis. Furthermore, this study revealed significance of anti-Gag proteins to predict high risk group in HTLV-1 carriers. Consistent with this finding, anti-Gag cytotoxic T lymphocytes (CTLs) were increased in patients who received hematopoietic stem cell transplantation and achieved remission state, indicating the significance of anti-Gag CTLs for disease control. Our findings suggest that our strategy that combines anti-HTLV-1 antibodies and proviral load may be useful for prediction of the development of HTLV-1-associated diseases.

Examining Adult T-Cell Leukemia/Lymphoma in the United States: A Hospital Based Study of Demographics and Survival Outcomes Focused on Hispanics

BACKGROUND: Adult T-cell leukemia/lymphoma (ATLL) is an aggressive neoplasm of mature CD4(+) T-cells caused by infection by Human T-lymphotropic virus type1 (HTLV-1) ( Arch Pathol Lab Med PMID: 24476526). ATLL affects 5% of those infected by HTLV-1, mainly in Africa, the Caribbean, Japan, and South America ( Rev Assoc Med Bras (1992) PMID: 27925051). In the United States (US) it is usually seen in immigrants from these regions ( Arch Pathol Lab Med PMID: 24476526). While there are treatment options for ATLL, it is often refractory to conventional chemotherapy and in general has a poor prognosis ( Actas Dermosifiliogr (Engl Ed) PMID: 29685460, Cancer Treat Res PMID: 30596217). Considering its poor outcomes and unique epidemiology, more information is needed regarding its effect in Hispanics (HI) vs Non-hispanics (NH) in the US. METHODS: Data were analyzed on ATLL patients in the US reported to the National Cancer Database (NCDB) between 2004 and 2019. Demographic and treatment characteristics were compared between ethnic groups. Kaplan-Meier and Cox regression analyses were used to compare overall survival (OS) between HI and NH populations. Multivariate analysis and propensity score matching was performed with adjustment for age, stage, comorbidity score, and insurance status, type of facility and great circle distance. RESULTS Of the 3073 ATLL patients studied between 2004 and 2019, 9% were HI, and 87% NH. In both groups, most here male with 65% of HI and 66% of NH. At diagnosis, HI patients were younger with a median age of 35 years vs. 42 years in NH (p&amp;lt;0.001). HI patients were more likely to be &amp;lt;65 at diagnosis 89% vs 83% (p=0.044). Most HI and NH patients identified as white (86% vs 68%), followed by black (4% vs 25%). Private insurance was the most common type in both groups (50% vs 57%), followed by government sponsored insurance (33% vs 36%). HI had a higher rate of being uninsured 12% vs 6% (p&amp;lt;0.001). Regarding Census Median Income (2008-2012), the most prevalent bracket for HI was $48,000 - $62,000 (28%), compared to NH $63,000+ (33%). HI were more likely to have an income of less than $38,000 (21% vs 18%) (p=0.512). HI also tended to live closer to their hospital (Great Circle Distance), with a median of 8.0 miles, vs NH at median of 11.6 miles (p=0.001). On survival analysis; the survival probability at 2, 5 and 10 years of HI vs NH were (64% vs 58%), (53% vs 48%), and (51% vs 43%), respectively. The median survival (MS) time was 3.7 years for NH and not reached for HI. The overall survival (OS) difference favoring HI was marginal and non-statistically significant (p=0.067). Independently, on multivariate analysis, NH ethnicity was not associated with worse OS (HR 1.25, CI 0.9-1.74, p=0.18). Interestingly, the propensity matched analysis demonstrated significant MS difference between HI vs NH (median 1.84 vs. 1.53 years). CONCLUSION Although the difference in OS in this study between HI and NH was not significant, there is a trend in the data showing increased survivability among HI despite patients in this group being more likely to be uninsured or in a lower income bracket. One possible explanation is that HI tended to present at an earlier age when compared to NH. It is evident that more data is needed to increase the power of these findings. Therefore, further study into the disease differences between these two groups, early detection, tumor markers, and targeted treatments will be necessary to improve the overall poor prognosis of this aggressive disease.

Clinical Outcomes of Tucidinostat Therapy for Relapsed/Refractory Adult T-Cell Leukemia-Lymphoma (ATL) in Clinical Practice

【Objective】 Tucidinostat, approved for relapsed/refractory adult T-cell leukemia-lymphoma (ATL) treatment in June 2021 in Japan, demonstrated an objective response rate (ORR) of 30.4%, progression-free survival (PFS) of 1.7 months (95% CI: 0.8-7.4), and overall survival (OS) of 7.9 months (95% CI: 2.3-18.0) in a phase IIb trial for 23 cases of relapsed/refractory adult T-cell leukemia-lymphoma (ATL) in Japan. We report the treatment results of this agent in Miyazaki Prefecture. 【Methods】 We retrospectively analyzed the treatment results of relapsed/refractory ATL patients who received Tucidinostat at 6 facilities within the Miyazaki prefecture, and HTLV-1 endemic area in southwest Japan, after its approval. All clinical procedures for patients were part of routine care, and the requirement for written patient consent was waived by the committee in view of the retrospective nature of this study. Approved study protocols were presented on the web site in an opt-out format, ensuring patients had the right to refuse participation in the study. In accordance with these protocols, clinical information was then collected. 【Results】 From October 2021 to July 2023, Tucidinostat was administered to 24 cases of relapsed/refractory ATL. The median age at the start of administration was 72.5 (41-85), with 13 cases of the acute type, 7 cases of the lymphoma type, and 4 cases of poor-prognosis chronic type. The median number of prior treatment regimens was 2 (1-4), with 19 cases of multi-drug combination chemotherapy, 18 cases of mogamulizumab, and 5 cases of oral chemotherapy. There were no cases of transplantation. The period from prior treatment to Tucidinostat administration was 3.2 months (0-27.5 months), and the disease stage at the start of Tucidinostat administration was relapse in 7 cases and refractory in 17 cases. The starting dose was 40mg/day (twice a week) in 19 cases and 20mg/day (twice a week) in 4 cases, with a median number of total treatment courses of 3 (1-20). Of the 24 cases,19 had their dose reduced or treatment suspended because of myelosuppression. The best treatment response was complete response(CR) in 5 cases, parcial response (PR) in 8 cases, Stable Disease(SD) in 8 cases, with an efficacy rate (CR/PR) of 54.2%. The PFS after the start of treatment was 3.7 months (1.8-7.8), and the OS after the start of treatment was 8.6 months. The reason for discontinuation of administration were progression disease in 15 cases, intolerance in 1 case (skin rash in 1 case), and severe complications in 1 case (cryptococcal meningitis). In the Cox proportional hazards model analysis, considering the clinical characteristics at the initiation of Tucidinostat, the initial sIL-2R level negatively impacted PFS. PFS was then stratified using an sIL-2R cutoff of 5000 U/mL, showing a Median Survival Time (MST) of PFS: 0.65 months for those below the cutoff versus 0.15 months for those above it, p=0.006 (log-rank).“A similar trend was observed for OS (Median OS: not reached vs. 0.53 months, p=0.032 (log-rank)). 【Conclusion】 In relapsed/refractory ATL, Tucidinostat achieved treatment results similar to those in the phase IIb trial in clinical practice. In particular, for cases with an sIL2-R value of less than 5000, it was suggested that Tucidinostat may be a meaningful treatment option.

Therapeutic approaches for HTLV-1-associated adult T-cell leukemia/lymphoma: a comprehensive review.

Adult T-cell leukemia/lymphoma (ATLL), an infrequent malignancy resultant from human T-cell lymphotropic virus type I (HTLV-1), exhibits a spectrum of phenotypes, encompassing acute, smoldering, lymphomatous, and chronic variants, each bearing distinct clinical presentations. The preponderant acute manifestation is characterized by hypercalcemia, systemic manifestations, organomegaly, and dermatological eruptions. Conversely, the chronic phenotype is typified by lymphocytosis and/or cutaneous eruptions, while smoldering ATLL assumes an asymptomatic course. Immunocompromise afflicts ATLL patients, heightening their vulnerability to opportunistic infections that frequently intricately intertwine with disease progression. Therefore, an early diagnosis is crucial to manage the disease appropriately. While conventional chemotherapeutic regimens have shown limited success, especially in acute and lymphoma types, recent studies suggest that allogeneic stem cell transplantation might enhance treatment results because it has shown promising outcomes in some patients. Novel therapeutics, such as interferon and monoclonal antibodies, have also shown promise, but more research is needed to confirm their efficacy. Moreover, the identification of biomarkers for ATLL and genetic changes in HTLV-1 infected cells has led to the development of targeted therapies that have shown remarkable success in clinical trials. These targeted therapies have the potential to offer a more personalized approach to the treatment of ATLL. The aim of our review is to elaborate on conventional and novel therapies and the efficiency of mentioned treatments.

CDK9 Inhibitor Induces Apoptosis, Autophagy, and Suppression of Tumor Growth in Adult T-Cell Leukemia/Lymphoma.

Adult T-cell leukemia/lymphoma (ATL) is a hematopoietic malignancy with a poor prognosis that develops in approximately 5% of human T-cell leukemia virus type 1 (HTLV-1) carriers. Cyclin-dependent kinase 9 (CDK9), together with Cyclin T, forms a transcription elongation factor, positive transcription elongation factor b (P-TEFb). P-TEFb promotes transcriptional elongation by phosphorylating the second serine (Ser2) of the seven amino acid repeat sequence in the C-terminal domain of RNA polymerase II (RNAP II). CDK9 inhibitors suppress cell proliferation by inducing apoptosis in chronic lymphocytic leukemia and breast cancer but there are no reports on autophagy of CDK9 inhibitors. Here, we investigated the effect of LY2857785, a novel CDK9 selective inhibitor, on cell death in ATL-related cell lines in vitro, freshly isolated cells from ATL patients ex vivo, and on ATL tumor xenografts in NOD/SCID mice in vivo. LY2857785 significantly reduced cell viability and induced apoptosis, as shown by annexin V-positive cells, cleaved poly(ADP-ribose) polymerase (PARP), and cleaved caspase-3, and suppressed the levels of anti-apoptotic protein myeloid cell leukemia-1 (MCL-1). LY2857785 decreased RNAP II Ser2 phosphorylation and downstream c-Myc protein levels. Interestingly, LY2857785 also increased microtubule-associated proteins 1A/1B light chain 3B (LC3)-II binding to autophagosome membranes. Furthermore, LY2857785 decreased the viability of freshly isolated ATL cells and induced apoptosis. Finally, LY2857785 significantly decreased the growth of ATL tumor xenografts. These results suggest that LY2857785 induces cell death of ATL cells by MCL-1-dependent apoptosis and autophagy and has anti-tumor activity.

Differential modulation of IL-4, IL-10, IL-17, and IFN-γ production mediated by IgG from Human T-lymphotropic virus-1 (HTLV-1) infected patients on healthy peripheral T (CD4+, CD8+, and γδ) and B cells.

Human T-lymphotropic virus 1 (HTLV-1) infected individuals remain as asymptomatic carriers (ACs) or can develop the chronic neurological disorder HTLV-1-associated myelopathy/Tropical Spastic Paraparesis (HAM/TSP) or the adult T-cell leukemia/lymphoma (ATLL), and the immunological mechanisms involved in this pathologies need to be elucidated. Recently, it has been demonstrated that induced or naturally developed IgG repertoires obtained from different groups of donors, grouped by immune status, can modulate human T and B cell functions. Here we aimed to evaluate if the IgG obtained from HTLV-1-infected ACs, HAM/TSP, and ATLL patients can differentially modulate the production of cytokines by human T and B cells. With this purpose, we cultured PBMCs with IgG purified from ACs, HAM/TSP, or ATLL donors and evaluated the frequency and intracellular cytokine production by flow cytometry. Our results indicate that IgG from HAM/TSP patients could induce an augment of IL-17-producing CD4+ T cells, reduce the frequency of IL-4-producing CD4+ T cells, increase IFN-γ-producing CD8+ T cells, and reduce IL-4-producing CD8+ T cells. IgG from ATLL could reduce the frequency of IL-4-producing CD4+ T cells, similarly to IgG from HAM/TSP /TSP, and could reduce the frequency of IFN-γ-producing γδT cells without influence on IL-17- and IL4-producing γδT and could reduce the frequency of IL-10- producing B cells. Finally, IgG from both HAM/TSP and ATLL patients could reduce the frequency of IFN-γ producing B cells. In conclusion, these results suggest that these preparations are active, partly overlapping in their effects, and able to elicit distinct effects on target populations.

Adult T-cell leukemia/lymphoma in HTLV-1 non-endemic regions

BackgroundHTLV-1 infection is a neglected disease, despite producing neurological and lymphoproliferative severe illnesses and affect over 10 million people worldwide. Roughly 5% of HTLV-1 carriers develop Adult T-cell leukemia/lymphoma (ATLL), one of the most aggressive hematological malignancies. MethodsA national HTLV-1 register exists since 1989 in Spain, a non-endemic country with a large migrant flow from Latin America and Equatorial Africa, where HTLV-1 is endemic. The main features of all patients diagnosed with ATLL in Spain up to date are reported. ResultsA total of 451 cases of HTLV-1 infection had been reported in Spain until the end of year 2022. ATLL had been diagnosed in 35 (7.8%). The current average incidence of ATLL in Spain is of two cases per year. Women represent 57% of ATLL patients. Mean age at diagnosis was 47 years-old. Roughly 57% were Latin Americans and 26% Africans. At diagnosis, the majority presented with acute or lymphoma clinical forms. Survival was shorter than one year in most of them.Mean HTLV-1 proviral load was significantly greater in ATLL patients than in asymptomatic HTLV-1 carriers (2,305 vs 104 copies/104 PBMC). HTLV-1 subtyping in 6 ATLL patients found the 1a transcontinental variant (n = 4) and the Japanese variant (n = 2). All ATLL patients were negative for HIV-1, did not develop HTLV-1-associated myelopathy and were not transplant recipients. ConclusionThe rate of ATLL is very low in Spain and mostly associated to migrants from HTLV-1 endemic regions. Given the poor clinical outcome of ATLL, HTLV-1 testing should be performed at least once in all migrants coming from HTLV-1 endemic countries and in natives who have lived in or had sex partners from such regions.