Romidepsin in Japanese patients with relapsed or refractory peripheral T-cell lymphoma: a phase I/II and pharmacokinetics study

Phase II Trial of Romidepsin as Consolidation Therapy after Gemcitabine, Dexamethasone, and Cisplatin in Elderly Transplant-Ineligible Patients with Relapsed/Refractory Peripheral T-Cell Lymphoma

Romidepsin is an important therapeutic option for patients with peripheral T-cell lymphoma (PTCL). However, the timing of romidepsin administration remains controversial. The objective of this study was to characterize the safety and efficacy of romidepsin as consolidation therapy after gemcitabine, dexamethasone, and cisplatin (GDP) therapy (GDPR). This study of patients treated between March 2019 and March 2021 was registered with the Japan Registry of Clinical Trials (registration number: jRCT0000000519). If complete response, partial response, or stable disease was confirmed after 2-4 GDP cycles, romidepsin was administered every 4 weeks for 1 year. Seven patients with relapsed/refractory (R/R) PTCL (T-follicular helper phenotype [n = 1] and angioimmunoblastic T-cell lymphoma [n = 6]) were included in this prospective study (PTCL-GDPR). After a median follow-up of 34 months of patients in PTCL-GDPR, the 2-year overall survival rate was 71%, and the overall response rate after treatment was 57%. Common adverse events in patients with PTCL-GDPR included hematological toxicities such as neutropenia, which improved with supportive treatment. There were no treatment-related mortalities. GDPR might be safe and effective in elderly transplant-ineligible patients with R/R PTCL; however, further investigation is required.

Improving gastrointestinal quality of life: romidepsin to tucidinostat in a case of angioimmunoblastic T cell lymphoma

Relapsed/refractory (R/R) peripheral T cell lymphoma (PTCL) has a poor prognosis, with limited treatment options and generally no durable response. However, long-term remission with the histone deacetylase (HDAC) inhibitor romidepsin has been reported, especially in angioimmunoblastic T cell lymphoma (AITL). Recently, tucidinostat, a novel oral HDAC inhibitor that selectively inhibits class I and class IIb HDACs, was approved for R/R PTCL in China and Japan. We present the case of a patient with AITL whose gastrointestinal symptoms and health-related quality of life improved after switching from romidepsin to tucidinostat as maintenance therapy. Romidepsin and tucidinostat appear to have different safety profiles; non-haematological toxicities such as nausea, vomiting, constipation, anorexia and fatigue may be reported less frequently with tucidinostat than with romidepsin. This case suggests that switching to tucidinostat therapy may be a viable option for patients with PTCL suffering from severe gastrointestinal adverse events with romidepsin.

Recommendations on prevention of infections in patients with T-cell lymphomas: a narrative review and synthesis

T/Natural killer (NK) cell lymphomas (TCL) represent a heterogenous subgroup of non-Hodgkin lymphoma, associated with poorer prognosis and higher treatment toxicity. A cohesive synthesis of infection outcomes among TCL patients is lacking. International guidelines offer no specific recommendations regarding prophylaxis or supportive infection care for TCL patients. This systematic narrative review highlights infection outcomes in TCL patients treated with conventional, and novel therapies. Recommendations for infection screening, antimicrobial prophylaxis and vaccination strategies are outined.

Update on histone deacetylase inhibitors in peripheral T-cell lymphoma (PTCL)

Peripheral T-cell lymphomas (PTCLs) are a group of highly aggressive malignancies with generally poor prognoses, and the first-line chemotherapy of PTCL has limited efficacy. Currently, several novel targeted agents, including histone deacetylase inhibitors (HDACis), have been investigated to improve the therapeutic outcome of PTCLs. Several HDACis, such as romidepsin, belinostat, and chidamide, have demonstrated favorable clinical efficacy and safety in PTCLs. More novel HDACis and new combination therapies are undergoing preclinical or clinical trials. Mutation analysis based on next-generation sequencing may advance our understanding of the correlation between epigenetic mutation profiles and relevant targeted therapies. Multitargeted HDACis and HDACi-based prodrugs hold promising futures and offer further directions for drug design.

Nodal peripheral T-cell lymphoma: Chemotherapy-free management, are we there yet?

Peripheral T-cell lymphomas (PTCLs) are a diverse and uncommon type of lymphoid malignancies with a dismal prognosis. Recent advances in genomic studies have shown recurring mutations that are changing our knowledge of the disease's molecular genetics and pathogenesis. As such, new targeted therapies and treatments to improve disease outcomes are currently being explored. In this review, we discussed the current understanding of the nodal PTCL biology with potential therapeutic implications and gave our insights on the promising novel therapies that are currently under study such as immunotherapy, chimeric antigen receptor T-cell therapy, and oncolytic virotherapy.

Efficacy and safety of histone deacetylase inhibitors in peripheral T-cell lymphoma: a systematic review and meta-analysis on prospective clinical trials

Background

The overall survival of peripheral T-cell lymphoma (PTCL) is dismal. Histone deacetylase (HDAC) inhibitors have exhibited promising treatment outcomes for PTCL patients. Therefore, this work aims to systematically evaluate the treatment outcome and safety profile of HDAC inhibitor-based treatment for untreated and relapsed/refractory (R/R) PTCL patients.

Methods

The prospective clinical trials of HDAC inhibitors for the treatment of PTCL were searched on the Web of Science, PubMed, Embase, ClinicalTrials.gov, and Cochrane Library database. The pooled overall response rate, complete response (CR) rate, and partial response rate were measured. The risk of adverse events was evaluated. Moreover, the subgroup analysis was utilized to assess the efficacy among different HDAC inhibitors and efficacy in different PTCL subtypes.

Results

For untreated PTCL, 502 patients in seven studies were involved, and the pooled CR rate was 44% (95% CI, 39-48%). For R/R PTCL patients, there were 16 studies included, and the CR rate was 14% (95% CI, 11-16%). The HDAC inhibitor-based combination therapy exhibited better efficacy when compared with HDAC inhibitor monotherapy for R/R PTCL patients (P = 0.02). In addition, the pooled CR rate was 17% (95% CI, 13-22%), 10% (95% CI, 5-15%), and 10% (95% CI, 5-15%) in the romidepsin, belinostat, and chidamide monotherapy subgroups, respectively. In the R/R angioimmunoblastic T-cell lymphoma subgroup, the pooled ORR was 44% (95% CI, 35-53%), higher than other subtypes. A total of 18 studies were involved in the safety assessment of treatment-related adverse events. Thrombocytopenia and nausea were the most common hematological and non-hematological adverse events, respectively.

Conclusion

This meta-analysis demonstrated that HDAC inhibitors were effective treatment options for untreated and R/R PTCL patients. The combination of HDAC inhibitor and chemotherapy exhibited superior efficacy to HDAC inhibitor monotherapy in the R/R PTCL setting. Additionally, HDAC inhibitor-based therapy had higher efficacy in angioimmunoblastic T-cell lymphoma patients than that in other subtypes.

Epigenetic targets in B- and T-cell lymphomas: latest developments

Non-Hodgkin's lymphomas (NHLs) comprise a diverse group of diseases, either of mature B-cell or of T-cell derivation, characterized by heterogeneous molecular features and clinical manifestations. While most of the patients are responsive to standard chemotherapy, immunotherapy, radiation and/or stem cell transplantation, relapsed and/or refractory cases still have a dismal outcome. Deep sequencing analysis have pointed out that epigenetic dysregulations, including mutations in epigenetic enzymes, such as chromatin modifiers and DNA methyltransferases (DNMTs), are prevalent in both B- cell and T-cell lymphomas. Accordingly, over the past decade, a large number of epigenetic-modifying agents have been developed and introduced into the clinical management of these entities, and a few specific inhibitors have already been approved for clinical use. Here we summarize the main epigenetic alterations described in B- and T-NHL, that further supported the clinical development of a selected set of epidrugs in determined diseases, including inhibitors of DNMTs, histone deacetylases (HDACs), and extra-terminal domain proteins (bromodomain and extra-terminal motif; BETs). Finally, we highlight the most promising future directions of research in this area, explaining how bioinformatics approaches can help to identify new epigenetic targets in B- and T-cell lymphoid neoplasms.

Oral HDAC inhibitor tucidinostat in patients with relapsed or refractory peripheral T-cell lymphoma: phase IIb results

Tucidinostat (formerly known as chidamide) is an orally available, novel benzamide class of histone deacetylase (HDAC) inhibitor that selectively blocks class I and class IIb HDAC. This multicenter phase IIb study aimed to investigate the efficacy and safety of tucidinostat, 40 mg twice per week (BIW), in patients with relapsed/refractory (R/R) peripheral T-cell lymphoma (PTCL). The primary endpoint was overall response rate (ORR) assessed by an independent overall efficacy review committee. Between March 2017 and March 2019, 55 patients were treated, and 46 and 55 were evaluated for efficacy and safety, respectively. Twenty-one of 46 patients achieved objective responses with an ORR of 46% (95% confidence interval : 30.9-61.0), including five patients with complete response (CR). Responses were observed across various PTCL subtypes. In angioimmunoblastic T-cell lymphoma, there were two CR and five partial responses (PR) among eight patients, achieving an ORR of 88%. The disease control rate (CR + PR + stable disease) was 72% (33/46). The median progression-free survival, duration of response, and overall survival were 5.6 months, 11.5 months, 22.8 months, respectively. The most common adverse events (AE) (all grades) were thrombocytopenia, neutropenia, leukopenia, anemia, and diarrhea. The grade ≥3 AE emerging in ≥20% of patients included thrombocytopenia (51%), neutropenia (36%), lymphopenia (22%), and leukopenia (20%). Importantly, most of the AE were manageable by supportive care and dose modification. In conclusion, the favorable efficacy and safety profiles indicate that tucidinostat could be a new therapeutic option in patients with R/R PTCL (clinicaltrials gov. Identifier: NCT02953652).

Synergistic antitumor effect of histone deacetylase class IIa inhibitor with lenvatinib in hepatocellular carcinoma

BACKGROUND

Histone deacetylase (HDAC) class I and IIa are highly expressed in hepatocellular carcinoma (HCC) and associated with decreased survival. However, clinically used pan and class I inhibitors have serious adverse events. In this study, we assessed the antitumor effects and tolerability of class IIa HDAC inhibitor (HDACI) with lenvatinib, which is a standard therapy for HCC.

METHODS AND RESULT

Combination therapy with class IIa HDACI and lenvatinib exerted synergistic antitumor effect in human HCC cell lines. In mouse models, this therapy showed significant antitumor effects, and few adverse events occurred. In immunoblotting, the expression of fibroblast growth factor receptor 4 (FGFR4) and fibroblast growth factor 19 (FGF19) was high in cell lines that showed a high antitumor effect. In addition, class IIa HDACI administration decreased the expression of FGFR4. In the small interfering RNA (siRNA) analysis, knockdown of HDAC9, which is an isoform of HDAC class IIa, reduced the expression of FGFR4 and induced apoptosis. Immunohistochemistry of human clinical specimens showed a positivity rate of 32% for FGFR4 and 84% for HDAC9 in HCC, and all FGFR4-positive patients were HDAC9 positive.

CONCLUSION

Class IIa HDACI and lenvatinib combination therapy induces apoptosis by downregulating FGFR4 and blocking the FGFR signaling in FGFR4-positive HCC cell lines and has demonstrated synergistic antitumor effects and safety. This combination therapy overcomes the problems of conventional therapies and will be beneficial for FGFR4-positive HCC patients.

Japanese subgroup analysis in the Asian phase II study of darinaparsin in patients with relapsed or refractory peripheral T-cell lymphoma

A Japanese subgroup analysis from the Asian phase II study of darinaparsin in patients with relapsed or refractory peripheral T-cell lymphoma (PTCL) was performed to evaluate the efficacy and safety outcomes of the Japanese population. In this Asian phase II study, darinaparsin was administered to 65 patients, including 37 Japanese patients. In the Japanese population, the histopathological type of PTCL was PTCL, not otherwise specified in 26 patients (70.3%), angioimmunoblastic T-cell lymphoma in 9 patients (24.3%) and anaplastic large cell lymphoma, anaplastic lymphoma kinase (ALK) -negative in 2 patients (5.4%), and the median patient age was 70.0 (range: 43-85). 94.6% and 35.1% of the Japanese population had previously received multi-agent and single-agent regimen, respectively. The efficacy and safety were summarized and compared between the overall and Japanese populations. Based on central assessment, the overall response rate was 22.2% (8/36; 90% confidence interval [CI]: 11.6-36.5) in the Japanese population and 19.3% (11/57; 90% CI: 11.2-29.9) in the overall population. There were no essential differences in the safety profile of darinaparsin between the Japanese population and the overall population. The results of this subgroup analysis indicate that the efficacy and safety profiles of the Japanese subpopulation were broadly consistent with that of the overall population, and that darinaparsin is potentially an effective treatment with a manageable safety profile in Japanese patients with relapse or refractory PTCL.

Precise diagnosis and targeted therapy of nodal T-follicular helper cell lymphoma (T-FHCL)

Nodal T-follicular helper cell lymphoma (T-FHCL) derived from T-follicular helper (Tfh) cell falls into a heterogeneous category of peripheral T-cell lymphoma (PTCL). Due to the limited number of therapeutic regimens and limited first-line efficacy, T-FHCL has a poor prognosis, and there is an urgent need for effective targeted therapies. With advancements in sequencing technologies, especially single-cell sequencing and next-generation sequencing, more specific genetic aberrations characteristic of T-FHCL can be discovered, allowing for precise molecular diagnosis and specific research on novel agents. Many biomarker-targeting agents, used either alone or in combination, have been tested, and they have generally enhanced the therapeutic outcomes of T-FHCL. Histone deacetylase inhibitors achieve significant clinical benefits in the treatment of T-FHCL, especially in combination therapy. Chimeric antigen receptor T-cell (CAR-T-cell) immunotherapies, hematopoietic stem cell transplantation, and other potential agents merit further study.

Oral histone deacetylase inhibitor HBI-8000 (tucidinostat) in Japanese patients with relapsed or refractory non-Hodgkin's lymphoma: phase I safety and efficacy

OBJECTIVE

HBI-8000 (tucidinostat) is a novel, oral histone deacetylase inhibitor that selectivity inhibits Class I (histone deacetylase 1, 2, 3) and Class II (histone deacetylase 10) with direct anti-tumor activity through various mechanisms of action, including epigenetic reprogramming and immunomodulation. It has been approved in China for the treatment of relapsed or refractory peripheral T-cell lymphoma.

METHODS

This multicenter, prospective phase I dose-escalation trial evaluating the safety of twice weekly HBI-8000 was conducted in Japan. Eligible patients had non-Hodgkin's lymphoma and no available standard therapy. The primary endpoint was maximum tolerated dose; secondary endpoints included anti-tumor activity, safety and pharmacokinetics.

RESULTS

Fourteen patients were enrolled in the study. Twelve patients were assessed for dose-limiting toxicity: six patients in the 30 mg BIW cohort had no dose-limiting toxicitys; two of six patients in the 40 mg BIW cohort had asymptomatic dose-limiting toxicitys. Treatment was well tolerated; adverse events were predominantly mild to moderate hematologic toxicities and were managed with dose modification and supportive care. Thirteen patients were included in the efficacy analysis. Objective response was seen in five of seven patients in the 40 mg BIW cohort; three partial responders had adult T-cell leukemia-lymphoma. In the 30 mg BIW cohort, three of six patients had stable disease after the first cycle.

CONCLUSIONS

Treatment with HBI-8000 30 and 40 mg BIW were well-tolerated and safe, with hematological toxicities as expected from other studies of histone deacetylase inhibitor. The maximum tolerated dose and recommended dosage for phase II studies of HBI-8000 is 40 mg BIW. Preliminary efficacy results are encouraging.

Establishment and characterization of two novel patient-derived myxoid liposarcoma cell lines

Myxoid liposarcoma (MLPS) is a lipogenic sarcoma, characterized by myxoid appearance histology and the presence of the FUS-DDIT3 fusion gene. MLPS shows frequent recurrence and poor prognosis after standard treatments, such as surgery. Therefore, novel therapeutic approaches for MLPS are needed. Development of novel treatments requires patient-derived cell lines to study the drug responses and their molecular backgrounds. Presently, only three cell lines of MLPS have been reported, and no line is available from public cell banks. Thus, this study aimed to establish and characterize novel MLPS cell lines. Using surgically resected tumor tissue from two patients with MLPS, two novel lines NCC-MLPS2-C1 and NCC-MLPS3-C1 were established. The presence of FUS-DDIT3 fusion, slow growth, spheroid formation, and invasive capability in these cell lines was confirmed. Growth retardation was monitored for 213 anti-cancer agents using NCC-MLPS2-C1 and NCC-MLPS3-C1 cells, and the results were integrated with the response to treatments in an MLPS cell line, NCC-MLPS1-C1, which was previously established in our laboratory. We found that romidepsin suppressed cell proliferation at considerably low concentrations in all three examined cell lines. NCC-MLPS2-C1 and NCC-MLPS3-C1 cell lines developed here represent a useful tool for basic and preclinical studies of MLPS.

Oral HDAC Inhibitor Tucidinostat (HBI-8000) in Patients with Relapsed or Refractory Adult T-cell Leukemia/Lymphoma: Phase IIb Results

This multicenter, prospective phase IIb trial evaluating the efficacy and safety of tucidinostat (HBI‐8000) in patients with relapsed or refractory (R/R) adult T‐cell leukemia/lymphoma (ATLL) was undertaken in Japan. Eligible patients had R/R ATLL and had failed standard of care treatment with chemotherapy and with mogamulizumab. Twenty‐three patients received tucidinostat 40 mg orally twice per week and were included in efficacy and safety analyses. The primary end‐point was objective response rate (ORR) assessed by an independent committee. The ORR was 30.4% (95% confidence interval [CI], 13.2, 52.9]. Median progression‐free survival was 1.7 months (95% CI, 0.8, 7.4), median duration of response was 9.2 months (95% CI, 2.6, not reached), and median overall survival was 7.9 months (95% CI, 2.3, 18.0). All patients experienced adverse events (AEs), which were predominantly hematologic and gastrointestinal. Incidence of grade 3 or higher AEs was 78.3%; most were laboratory abnormalities (decreases in platelets, neutrophils, white blood cells, and hemoglobin). Tucidinostat was well tolerated with AEs that could be mostly managed with supportive care and dose modifications. Tucidinostat is a meaningful treatment option for R/R ATLL patients; further investigation is warranted.

The Status and Prospects of Epigenetics in the Treatment of Lymphoma

The regulation of gene transcription by epigenetic modifications is closely related to many important life processes and is a hot research topic in the post-genomic era. Since the emergence of international epigenetic research in the 1990s, scientists have identified a variety of chromatin-modifying enzymes and recognition factors, and have systematically investigated their three-dimensional structures, substrate specificity, and mechanisms of enzyme activity regulation. Studies of the human tumor genome have revealed the close association of epigenetic factors with various malignancies, and we have focused more on mutations in epigenetically related regulatory enzymes and regulatory recognition factors in lymphomas. A number of studies have shown that epigenetic alterations are indeed widespread in the development and progression of lymphoma and understanding these mechanisms can help guide clinical efforts. In contrast to chemotherapy which induces cytotoxicity, epigenetic therapy has the potential to affect multiple cellular processes simultaneously, by reprogramming cells to achieve a therapeutic effect in lymphoma. Epigenetic monotherapy has shown promising results in previous clinical trials, and several epigenetic agents have been approved for use in the treatment of lymphoma. In addition, epigenetic therapies in combination with chemotherapy and/or immunotherapy have been used in various clinical trials. In this review, we present several important epigenetic modalities of regulation associated with lymphoma, summarize the corresponding epigenetic drugs in lymphoma, and look at the future of epigenetic therapies in lymphoma.

Efficacy and Treatment-Related Adverse Events of Romidepsin in PTCL Clinical Studies: A Systematic Review and Meta-Analysis

Background: Peripheral T-cell lymphoma (PTCL) is an extensive class of biologically and clinically heterogeneous diseases with dismal outcomes. The histone deacetylase inhibitor (HDACi) romidepsin was approved for relapsed and refractory (R/R-PTCL) in 2011. This meta-analysis was performed to assess the efficacy and safety of romidepsin in PTCL.

Methods: We searched for articles on the HDAC inhibitor romidepsin in the treatment of PTCL in Embase, Web of Science, and PubMed. The methodology is further detailed in PROSPERO (CRD42020213651, CRD42020213553). The 2-year overall survival (OS), 2-year progression-free survival (PFS), and their corresponding to 95% confidence intervals (CIs) were measured. Besides, corresponding 95% CIs were pooled for the complete response (CR), partial response (PR), duration of response (DoR), and risk of adverse events (AEs).

Results: Eleven studies containing 388 patients were incorporated into the quantitative synthesis, of which R/R-PTCL patients were the dominant portion, accounting for 94.3% (366/388). For all studies, the CR rate was 20% (95% CI, 13–27%, random effects model), and the PR rate was 18% (95% CI, 12–25%, random effects model). The 2-year OS was 48% (95% CI, 38–59%, fixed effects model), and the 2-year PFS was 17% (95% CI, 13–21%, fixed effects model). There were no significant differences between romidepsin monotherapy and romidepsin plus additional drugs. Hematological toxicities, such as lymphopenia and granulocytopenia, remained the most continually happening grade 3 or higher AEs, accounting for 46 and 28%, respectively. None of the studies reported any drug-related mortality.

Conclusions: Considering that most of the included patients had R/R-PTCL, the addition of romidepsin significantly enhance the efficacy. And AEs were tolerable as the grade 3/4 AEs in romidepsin monotherapy was 7% (95% CI, 6–8%). It is imperative to further expand the first-line application of romidepsin and carry out personalized therapy based on epigenomics, which will improve the survival of PTCL patients.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020213651 and https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020213553.

Biology and Molecular Pathogenesis of Mature T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) constitute a highly heterogeneous group of hematological diseases with complex clinical and molecular features consistent with the diversity of the T-cell type from which they originate. In the past several years, the systematic implementation of high-throughput genomic technologies for the analysis of T-cell malignancies has supported an exponential progress in our understanding of the genetic drivers of oncogenesis and unraveled the molecular complexity of these diseases. Recent findings have helped redefine the classification of T-cell malignancies and provided novel biomarkers to improve diagnosis accuracy and analyze the response to therapy. In addition, multiple novel targeted therapies including small-molecule inhibitors, antibody-based approaches, and immunotherapy have shown promising results in early clinical analysis and have the potential to completely change the way T-cell malignancies have been treated traditionally.

Optimal therapeutic targeting by HDAC inhibition in biopsy-derived treatment-naïve diffuse midline glioma models

BACKGROUND

Diffuse midline gliomas (DMGs), including diffuse intrinsic pontine gliomas (DIPGs), have a dismal prognosis, with less than 2% surviving 5 years postdiagnosis. The majority of DIPGs and all DMGs harbor mutations altering the epigenetic regulatory histone tail (H3 K27M). Investigations addressing DMG epigenetics have identified a few promising drugs, including the HDAC inhibitor (HDACi) panobinostat. Here, we use clinically relevant DMG models to identify and validate other effective HDACi and their biomarkers of response.

METHODS

HDAC inhibitors were tested across biopsy-derived treatment-naïve in vitro and in vivo DMG models with biologically relevant radiation resistance. RNA sequencing was performed to define and compare drug efficacy and to map predictive biomarkers of response.

RESULTS

Quisinostat and romidepsin showed efficacy with low nanomolar half-maximal inhibitory concentration (IC50) values (~50 and ~5 nM, respectively). Comparative transcriptome analyses across quisinostat, romidepsin, and panobinostat showed a greater degree of shared biological effects between quisinostat and panobinostat, and less overlap with romidepsin. However, some transcriptional changes were consistent across all 3 drugs at similar biologically effective doses, such as overexpression of troponin T1 slow skeletal type (TNNT1) and downregulation of collagen type 20 alpha 1 chain (COL20A1), identifying these as potential vulnerabilities or on-target biomarkers in DMG. Quisinostat and romidepsin significantly (P < 0.0001) inhibited in vivo tumor growth.

CONCLUSIONS

Our data highlight the utility of treatment-naïve biopsy-derived models; establishes quisinostat and romidepsin as effective in vivo; illuminates potential mechanisms and/or biomarkers of DMG cell lethality due to HDAC inhibition; and emphasizes the need for brain tumor-penetrant versions of potentially efficacious agents.

Therapeutic applications and biological activities of bacterial bioactive extracts

Bacteria are rich in a wide variety of secondary metabolites, such as pigments, alkaloids, antibiotics, and others. These bioactive microbial products serve a great application in human and animal health. Their molecular diversity allows these natural products to possess several therapeutic attributes and biological functions. That's why the current natural drug industry focuses on uncovering all the possible ailments and diseases that could be combated by bacterial extracts and their secondary metabolites. In this paper, we review the major utilizations of bacterial natural products for the treatment of cancer, inflammatory diseases, allergies, autoimmune diseases, infections and other diseases that threaten public health. We also elaborate on the identified biological activities of bacterial secondary metabolites including antibacterial, antifungal, antiviral and antioxidant activities all of which are essential nowadays with the emergence of drug-resistant microbial pathogens. Throughout this review, we discuss the possible mechanisms of actions in which bacterial-derived biologically active molecular entities could possess healing properties to inspire the development of new therapeutic agents in academia and industry.

Small Molecules Targeting HATs, HDACs, and BRDs in Cancer Therapy

Evidence for research over the past decade shows that epigenetic regulation mechanisms run through the development and prognosis of tumors. Therefore, small molecular compounds targeting epigenetic regulation have become a research hotspot in the development of cancer therapeutic drugs. According to the obvious abnormality of histone acetylation when tumors occur, it suggests that histone acetylation modification plays an important role in the process of tumorigenesis. Currently, as a new potential anti-cancer therapeutic drugs, many active small molecules that target histone acetylation regulatory enzymes or proteins such as histone deacetylases (HDACs), histone acetyltransferase (HATs) and bromodomains (BRDs) have been developed to restore abnormal histone acetylation levels to normal. In this review, we will focus on summarizing the changes of histone acetylation levels during tumorigenesis, as well as the possible pharmacological mechanisms of small molecules that target histone acetylation in cancer treatment.

Comparison of prognostic scores in transplant-ineligible patients with peripheral T-cell lymphoma not otherwise specified and angioimmunoblastic T-cell lymphoma: a retrospective study from the national hospital organization in Japan

We retrospectively analyzed the risk factors for outcomes among patients with peripheral T-cell lymphoma not otherwise specified (PTCL-NOS, n = 100) and angioimmunoblastic T-cell lymphoma (AITL, n = 128) who did not receive hematopoietic stem cell transplantation between 2008 and 2018. We designed a comparison of prognostic scores specifically for PTCL-NOS and AITL. The international prognostic index (IPI) was useful for investigating the risk factors associated with outcomes among transplant-ineligible patients with PTCL-NOS (Harrell's c-statistic 0.715) and AITL (c-statistic 0.615). The prognostic index for T-cell lymphoma (PIT), modified PIT, and the International Peripheral T Cell Lymphoma Project for overall survival (OS) seemed to identify separate prognostic groups, based on visual assessment of Kaplan-Meier curves. However, better c-statistics (>0.7) were only found for the IPI score for OS in PTCL-NOS. Strategies that carefully select PTCL patients with higher IPI scores may help to identify individuals suitable for novel therapies.

Characterization of Regulatory and Transporter Genes in the Biosynthesis of Anti-Tuberculosis Ilamycins and Production in a Heterologous Host

Ilamycins are cyclopeptides with novel structures that have been isolated from different Actinomycetes. They showed strong anti-tuberculosis activity and could serve as important anti-tuberculosis drug leads. The functions of the pre-tailoring and the post-tailoring genes in the biosynthesis of ilamycins have been elucidated, but the functions of the regulatory and transporter genes remain elusive. We reported herein the functions of four genes in ilamycin biosynthetic gene cluster (ila BGC) including two regulatory genes (ilaA and ilaB) and two transporter genes (ilaJ and ilaK) and the heterologous expression of ila BGC. The IlaA and IlaB were unambiguously shown to be negative and positive regulator of ilamycins biosynthesis, respectively. Consistent with these roles, inactivation of ilaA and ilaB (independent of each other) was shown to enhance and abolish the production of ilamycins, respectively. Total yields of ilamycins were enhanced 3.0-fold and 1.9-fold by inactivation of ilaA and overexpression of ilaB compared to those of in the Streptomyces atratus SCSIO ZH16, respectively. In addition, the ila BGC was successfully expressed in Streptomyces coelicolor M1152, which indicated that all biosynthetic elements for the construction of ilamycins were included in the PAC7A6. These results not only lay a foundation for further exploration of ilamycins, but also provide the genetic elements for synthetic biology.

Effects of stem cell transplantation in patients with peripheral T-cell lymphoma not otherwise specified and angioimmunoblastic T-cell lymphoma

The effects of stem cell transplantation (SCT) in patients with peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) and angioimmunoblastic T-cell lymphoma (AITL) remain controversial. We analyzed the feasibility of SCT and risk factors associated with outcomes of PTCL-NOS and AITL patients to identify the potential clinical efficacy of SCT. We retrospectively analyzed the data of PTCL-NOS (n = 83) and AITL (n = 112) patients who received autologous (n = 10 and 16, respectively) or allogeneic (n = 12 and 4, respectively) SCT, or no SCT (n = 61 and 92, respectively) between 2008 and 2018. All PTCL-NOS and AITL diagnoses were reconfirmed by an experienced hematopathologist. Median age at PTCL-NOS and AITL diagnoses in the SCT group was younger than that in the no SCT group. Significant risk factors for lower overall survival were intermediate-high and high-risk international prognostic indexes in PTCL-NOS patients (P = 0.0052), and a > 2 modified prognostic index for T-cell lymphoma (P = 0.0079) and no SCT (P = 0.028) in AITL patients. Autologous or allogeneic SCT compared with no SCT in AITL patients resulted in 3-year overall survival of 68.6% and 100% vs. 57.2% (P = 0.018). Strategies should be developed to improve selection of PTCL-NOS and AITL patients suitable for SCT and/or additional novel therapies.

Targeting epigenetic regulators in the treatment of T-cell lymphoma

Introduction: T-cell lymphomas represent a broad group of malignant T-cell neoplasms with marked molecular, clinical, and biologic heterogeneity. Survival rates after conventional chemotherapy regimens are poor for most subtypes and new therapies are needed. Rapidly expanding knowledge in the field of epigenomics and the development of an increasing number of epigenetic-modifying agents have created new opportunities for epigenetic therapies for patients with this complex group of diseases.Areas covered: The present review summarizes current knowledge on epigenetic alterations in T-cell lymphomas, availability, and mechanisms of action of epigenetic-modifying agents, results of clinical trials of epigenetic therapies in T-cell lymphomas, status of FDA approval, and biomarker approaches to guide therapy. Promising future directions are discussed.Expert opinion: Mutations in epigenetic-modifying genes are among the most common genetic alterations in T-cell lymphomas, highlighting the potential for epigenetic therapies to improve management of this group of diseases. Single-agent efficacy is well documented, leading to FDA approval for several indications, but overall response rates and durability of responses remain modest. Critical next steps for the field include optimizing combination therapies that incorporate epigenetic-modifying agents and developing predictive biomarkers that help guide patient and drug selection.

The Role of Epigenetic Modifications in Systemic Sclerosis: A Druggable Target

Systemic sclerosis (SSc) is a rare autoimmune disorder characterised by skin fibrosis that often also affects internal organs, eventually resulting in mortality. Although management of the symptoms has extended lifespan, patients still suffer from poor quality of life, hence the need for improved therapies. Development of efficacious treatments has been stymied by the unknown aetiology, although recent advancements suggest a potentially key role for epigenetics - the regulation of gene expression by noncoding RNAs and chemical modifications to DNA or DNA-associated proteins. Herein, the evidence implicating epigenetics in the pathogenesis of SSc is discussed with an emphasis on the therapeutic potential this introduces to the field - particularly the repurposing of epigenetic targeting cancer therapeutics and newly emerging miRNA-based strategies.

Risk factors and timing of autologous stem cell transplantation for patients with peripheral T-cell lymphoma

High-dose chemotherapy with autologous stem cell transplantation (HDC-ASCT) is an option for patients with peripheral T-cell lymphoma (PTCL); however, neither prospective nor retrospective studies support proceeding with ASCT upfront, and the timing of HDC-ASCT remains controversial. We retrospectively analyzed the risk factors for outcomes of 570 patients with PTCL, including PTCL not otherwise specified (PTCL-NOS) and angioimmunoblastic T-cell lymphoma (AITL), who received ASCT for frontline consolidation (n = 98 and 75, respectively) or alternative therapies after either relapse (n = 112 and 75) or primary induction failure (PIF; n = 127 and 83) between 2000 and 2015. Significant risk factors for overall survival (OS) after upfront ASCT were a ≥ 2 prognostic index for T-cell lymphoma (P < 0.001) and partial response (PR) at ASCT (P = 0.041) in PTCL-NOS patients, and > 60 years of age (P = 0.0028) and PR at ASCT (P = 0.0013) in AITL patients. Performance status of ≥ 2 at ASCT (P < 0.001), receiving ≥ 3 regimens before ASCT (P = 0.018), and PR at ASCT (P = 0.018) in PTCL-NOS patients and > 60 years of age at ASCT (P = 0.0077) in AITL patients were risk factors for OS after ASCT with a chemosensitive PIF status. Strategies that carefully select PTCL patients may allow identification of individuals suitable for ASCT.

Forodesine in the treatment of relapsed/refractory peripheral T-cell lymphoma: an evidence-based review

T-cell lymphoma is a rare hematologic malignancy with an incidence rate between 10% and 20% of that of non-Hodgkin lymphomas. Patients with peripheral T-cell lymphoma (PTCL) generally have a poor prognosis when treated with cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP)/CHOP-like chemotherapy; once relapse occurs, it is mostly regarded as an incurable disease. To overcome the chemorefractoriness of PTCL, several novel agents have been developed. Since the first approval of pralatrexate, a dihydrofolate reductase inhibitor, for relapsed/refractory PTCL by the US Food and Drug Administration, several new agents, such as romidepsin (histone deacetylase inhibitor), brentuximab vedotin (antibody–drug conjugate targeting CD30), chidamide (histone deacetylase inhibitor), and mogamulizumab (anti-CC chemokine receptor 4 monoclonal antibody), have been approved as a therapeutic option for relapsed/refractory PTCL in several countries, including the US, Europe, China, and Japan. Forodesine is a novel, potent purine nucleoside phosphorylase inhibitor that is effective against T-cell malignancies. Although the clinical development of forodesine was discontinued in the US and Europe, a multicenter Phase I/II study of oral forodesine for relapsed PTCL was recently completed in Japan. The overall response rate was 24% (10 of 41 patients), which included four patients with complete response. In general, the toxicity of forodesine is manageable. As the study met the primary end point, forodesine was approved for the treatment of relapsed/refractory PTCL in Japan in March 2017, which was the first approval of forodesine in the world. As forodesine is an oral formulation, it is more convenient than other novel intravenous agents approved for PTCL. However, it is necessary to appropriately manage opportunistic infections and secondary lymphomas possibly associated with long-lasting lymphocytopenia caused by forodesine. In this manuscript, we have summarized the currently available evidence for forodesine and discussed the clinical implications for PTCL treatment.

Recent advances in understanding and managing T-cell lymphoma

Owing to the rarity of peripheral T-cell lymphoma (PTCL) and the heterogeneity of subtypes, there are no compelling data to guide the therapeutic approaches for such patients. Over the years, there have been remarkable advances in molecular subtyping and treatment of PTCL, although there are still many areas to be explored. In this review, we summarize recent updates on the evolution of understanding and treatment for PTCL.