Epigenetic alterations and advancement of treatment in peripheral T-cell lymphoma

The efficacy and safety of brentuximab vedotin for peripheral T-cell lymphoma: A systemic review and meta-analysis

Peripheral T-cell lymphoma (PTCL) is an extensive class of heterogeneous diseases with dismal outcomes. Brentuximab vedotin (BV) is an antibody-drug conjugate (ADC) comprising a CD30-directed antibody. This review aimed to evaluate the efficacy and safety of BV for treating PTCL. We searched the PubMed, Embase, Cochrane Library, and Web of Science databases for studies evaluating the efficacy of BV alone or in combination with other drugs for treating PTCL. The primary outcome measures included objective response rate (ORR), complete remission (CR), progression-free survival (PFS), and overall survival (OS). The secondary outcomes included 5-year OS, 5-year PFS, and adverse events. 22 studies involving 1137 patients were included. These studies reported the use patterns of BV, ORR, CR, PFS, OS, and adverse events. The pooled ORR and CR rates were 68% (95% CI: 59%-75%) and 43% (95% CI: 34%-53%). For survival outcomes, the longest median PFS was 8.3 months, and the longest median OS was 26.3 months. The most common adverse event was peripheral neuropathy and neutropenia. The analysis suggested that BV alone or in combination with other drugs improved the response and survival rates in PTCL patients and was associated with tolerable adverse effects.

Targeting PTGDS Promotes ferroptosis in peripheral T cell lymphoma through regulating HMOX1-mediated iron metabolism

BACKGROUND

Peripheral T cell lymphoma (PTCL) is characterized by high heterogeneity, strong aggressiveness, and extremely poor prognosis. Ferroptosis, a novel form of programmed cell death, has been involved in tumor development and targeting ferroptosis holds great potential for tumor therapy.

METHODS

Lentiviral transfection was performed to regulate gene expression, followed by Tandem mass tag (TMT)-mass spectrometry and RNA-sequencing. Tumor xenograft models were established for in vivo experiments.

RESULTS

High expression of prostaglandin D2 synthase (PTGDS) was closely associated with poor prognosis of PTCL patients. PTGDS knockdown and AT56 treatment significantly inhibited the progression of PTCL through regulating cell viability, proliferation, apoptosis, cell cycle and invasion in vitro and in vivo. We further revealed that targeting PTGDS promoted ferroptosis process and enhanced the sensitivity of PTCL cells to ferroptosis inducers Sorafenib in vitro and in vivo. Mechanically, PTGDS interacted with heme-degrading enzymes HMOX1, and targeting PTGDS increased the level of iron and induced ferroptosis in PTCL through promoting HMOX1-mediated heme catabolism and ferritin autophagy process. Through the construction of H25A mutation, the specific gene site of HMOX1 corresponding to its role was identified.

CONCLUSIONS

Taken together, our findings firstly identified that targeting PTGDS promotes the ferroptosis in PTCL through regulating HMOX1-mediated iron metabolism, and highlighted novel therapeutic strategies to improve the efficacy of ferroptosis-targeted therapy in PTCL patients.

Chidamide and venetoclax synergistically regulate the Wnt/β-catenin pathway by MYCN/DKK3 in B-ALL

B-cell acute lymphocytic leukemia (B-ALL) is a malignant proliferative B-lymphocyte disease. Although the outcome of B-ALL has greatly improved with combined chemotherapy, immunotherapy, and hematopoietic stem cell transplantation, some patients still experience drug resistance, relapse and a low long-term survival rate, therefore, finding novel approaches to improve the outcome of adult B-ALL patients is critical. Our previous studies revealed that the selective histone deacetylase inhibitor (HDACi) chidamide can inhibit the Wnt/β-catenin signaling pathway by inhibiting MYCN and increasing the expression of DKK3 in B-ALL cells. Some studies have indicated that histone deacetylase inhibitors (HDACis) can dysregulate the B-cell lymphoma-2 (BCL2) protein family, we speculate that chidamide and BCL2 inhibitor venetoclax synergistically inhibit the Wnt/β-catenin signaling pathway by inhibiting MYCN expression and increasing DKK3 expression. In our study, the in vitro and in vivo experiments confirmed that chidamide and venetoclax synergistically inhibited the expression of MYCN and increased the expression of DKK3 by inhibiting the activity of HDAC and BCL2, inhibiting the Wnt/β-catenin signaling pathway and B-ALL cell proliferation. These findings indicate that the HDACi chidamide and the BCL2 inhibitor venetoclax can be used in combination to treat B-ALL, providing a new method and strategy for treating B-ALL.

Comprehensive genomic analysis reveals molecular heterogeneity in pediatric ALK-positive anaplastic large cell lymphoma

Anaplastic large cell lymphoma (ALCL) is a mature T-cell lymphoma that accounts for 10-15% of childhood lymphomas. Despite the observation that more than 90% of pediatric cases harbor the anaplastic lymphoma kinase (ALK) rearrangement resulting in aberrant ALK kinase expression, there is significant clinical, morphologic, and biological heterogeneity. To gain insights into the genomic aberrations and molecular heterogeneity within ALK-positive ALCL (ALK+ ALCL), we analyzed 46 pediatric ALK+ ALCLs by whole-exome sequencing, RNA sequencing, and DNA methylation profiling. Whole-exome sequencing found on average 25 SNV/Indel events per sample with recurring genetic events in regulators of DNA damage (TP53, MDM4), transcription (JUNB), and epigenetic regulators (TET1, KMT2B, KMT2A, KMT2C, KMT2E). Gene expression and methylation profiling consistently subclassified ALK+ ALCLs into two groups characterized by differential ALK expression levels. The ALK-low group showed enrichment of pathways associated with immune response, cytokine signaling, and a hypermethylated predominant pattern compared to the ALK-high group, which had more frequent copy number changes and was enriched with pathways associated with cell growth, proliferation, and metabolism. Altogether, these findings suggest that there is molecular heterogeneity within pediatric ALK+ ALCL, predicting distinct biological mechanisms that may provide novel insights into disease pathogenesis and represent prognostic markers.

cyTRBC1 evaluation rapidly identifies sCD3-negative peripheral T-cell lymphomas and reveals a novel type of sCD3-negative T-cell clone with uncertain significance

The flow cytometry-based evaluation of TRBC1 expression has been demonstrated as a rapid and specific method for detecting T-cell clones in sCD3-positive TCRαβ+ mature T-cell lymphoma. The aim of the study was to validate the utility of surface (s) TRBC1 and cytoplastic (cy) TRBC1 assessment in detecting clonality of sCD3-negative peripheral T-cell lymphomas (PTCLs), as well as exploring the existence and characteristics of sCD3-negative clonal T-cell populations with uncertain significance (T-CUS). Evaluation of sTRBC1 and cyTRBC1 were assessed on 61 samples from 37 patients with sCD3-negative PTCLs, including 26 angioimmunoblastic T-cell lymphoma (AITL) patients and 11 non-AITL patients. The sCD3-negative T-CUS were screened from 1602 patients without T-cell malignancy and 100 healthy individuals. Additionally, the clonality of cells was further detected through T-cell gene rearrangement analysis. We demonstrated the monotypic expression patterns of cyTRBC1 in all sCD3-negative PTCLs. Utilizing the cyTRBC1 evaluation assay, we identified a novel and rare subtype of sCD3-negative T-CUS for the first time among 13 out of 1602 (0.8%) patients without T-cell malignancy. The clonality of these cells was further confirmed through T-cell gene rearrangement analysis. This subset exhibited characteristics such as sCD3-cyCD3 + CD4 + CD45RO+, closely resembling AITL rather than non-AITL. Further analysis revealed that sCD3-negative T-CUS exhibited a smaller clone size in the lymph node and mass specimens compared to AITL patients. However, the clone size of sCD3-negative T-CUS was significantly lower than that of non-AITL patients in both specimen groups. In conclusion, we validated the diagnostic utility of cyTRBC1 in detecting sCD3-negative T-cell clonality, provided a comprehensive analysis of sCD3-negative T-CUS, and established a framework and provided valuable insights for distinguishing sCD3-negative T-CUS from sCD3-negative PTCLs based on their phenotypic properties and clone size.

Comparison of tucidinostat with CHOP-like versus CHOP-like in first-line treatment of peripheral T-cell lymphoma: a single-center real-world study

Tucidinostat has been approved by the Chinese FDA for relapsed/refractory Peripheral T cell lymphoma (PTCL), but its efficacy in newly diagnosed PTCL has not been confirmed. In this study, we aimed to compare the efficacy of tucidinostat combined with CHOP-like (C + CHT) versus CHOP-like alone (CHT) in newly diagnosed PTCL patients. Of the PTCL patients, 109 were newly diagnosed. Patients in the C + CHT group who achieved objective response received tucidinostat maintenance therapy. A total of 36 pairs (n = 72) were matched at a ratio of 1:1 using propensity scoring. The matching criteria included: whether the Prognostic index for the peripheral T-cell lymphoma-not otherwise specified subtype (PIT) was ≥ 2, the pathological subtype, age > 60 years, and gender (matching tolerance = 0.024). A significantly higher objective response rate (ORR) (P = 0.016), 2-year progression-free survival (PFS) (P = 0.026), and 2-year survival rate (P = 0.017) was observed for the C + CHT group as compared to the CHT group. After propensity score matching (PSM), the C + CHT group as compared to the CHT group displayed significantly longer PFS (P = 0.035) and overall survival (OS) (P = 0.029). For the C + CHT group in the per-protocol set, the effect values showed a significant benefit in terms of both PFS (P = 0.027) and OS (P = 0.019). Common grade 3-4 haematological adverse events (AEs), had comparable incidence in each group; while common non-haematological AEs, including elevated AST and ALT were higher in the C + CHT group than in the CHT group. Our study suggests that the tucidinostat with CHOP-like regimen and sequential tucidinostat maintenance after objective remission provides a promising therapeutic approach for treating newly diagnosed PTCL patients.

Lack of SMARCB1 expression characterizes a subset of human and murine peripheral T-cell lymphomas

Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) is a heterogeneous group of malignancies with poor outcome. Here, we identify a subgroup, PTCL-NOSSMARCB1-, which is characterized by the lack of the SMARCB1 protein and occurs more frequently in young patients. Human and murine PTCL-NOSSMARCB1- show similar DNA methylation profiles, with hypermethylation of T-cell-related genes and hypomethylation of genes involved in myeloid development. Single-cell analyses of human and murine tumors revealed a rich and complex network of interactions between tumor cells and an immunosuppressive and exhausted tumor microenvironment (TME). In a drug screen, we identified histone deacetylase inhibitors (HDACi) as a class of drugs effective against PTCL-NOSSmarcb1-. In vivo treatment of mouse tumors with SAHA, a pan-HDACi, triggered remodeling of the TME, promoting replenishment of lymphoid compartments and reversal of the exhaustion phenotype. These results provide a rationale for further exploration of HDACi combination therapies targeting PTCL-NOSSMARCB1- within the TME.

Yttrium-90 anti-CD25 BEAM conditioning for autologous hematopoietic cell transplantation in Peripheral T-cell lymphoma

ABSTRACT

Peripheral T-cell lymphomas (PTCLs) have a poor prognosis with current treatments. High-dose chemotherapy followed by autologous hematopoietic cell transplant (AHCT) is used as a consolidation strategy after achieving clinical remission with first-line therapy, as well as in chemotherapy-sensitive relapse if allogeneic transplant is not an option. CD25 is a targetable protein often highly expressed in PTCLs. In this phase 1 clinical trial, we tested the addition of β-emitting 90yttrium (90Y)-labeled chimeric anti-CD25 basiliximab (aTac) to BEAM (carmustine, etoposide, cytarabine, and melphalan) as conditioning for AHCT for patients with PTCL. Twenty-three AHCT-eligible patients were enrolled, and 20 received therapeutic 90Y-aTac-BEAM AHCT. Radiation doses of 0.4, 0.5, and 0.6 mCi/kg were tested. With no observed dose-limiting toxicities, 0.6 mCi/kg was deemed the recommended phase 2 dose. The most prevalent adverse effect, grade 2 mucositis, was experienced by 80% of patients. As of this report, 6 (30%) of the treated patients had died, 5 due to progressive disease and 1 due to multiple organ failure (median time of death, 17 months [range, 9-21]) after AHCT. Median follow-up was 24 months (range, 9-26) overall and 24 months (range, 13-26) for surviving patients. For patients who received therapeutic 90Y-aTac-BEAM AHCT, the 2-year progression-free and overall survival were 59% (95% confidence interval [CI], 34-77) and 68% (95% CI, 42-84), respectively. 90Y-aTac-BEAM appears to be safe as an AHCT conditioning regimen for PTCL, with no increased toxicity over the toxicities historically seen with BEAM alone in this patient population. This trial was registered at www.ClinicalTrials.gov as #NCT02342782.

Phase 2 trial of the farnesyltransferase inhibitor tipifarnib for relapsed/refractory peripheral T-cell lymphoma

ABSTRACT

A phase 2, international, open-label, nonrandomized, single-arm trial was conducted to evaluate the efficacy and safety of tipifarnib, a farnesyltransferase inhibitor, as monotherapy for relapsed/refractory peripheral T-cell lymphoma (PTCL) and to evaluate tumor mutation profile as a biomarker of response. Adults with relapsed/refractory PTCL received tipifarnib 300 mg orally twice daily for 21 days in a 28-day cycle. The primary end point was objective response rate (ORR); secondary end points included ORR, progression-free survival (PFS), duration of response (DOR), and adverse events (AEs) in specific subtypes. Sixty-five patients with PTCL were enrolled: n = 38 angioimmunoblastic T-cell lymphoma (AITL), n = 25 PTCL not otherwise specified, and n = 2 other T-cell lymphomas. The ORR was 39.7% (95% confidence interval [CI], 28.1-52.5) in all patients and 56.3% (95% CI, 39.3-71.8) for AITL. Median PFS was 3.5 months overall (954% CI, 2.1-4.4), and 3.6 months (95% CI, 1.9-8.3) for AITL. Median DOR was 3.7 months (95% CI, 2.0-15.3), and greatest in patients with AITL (7.8 months; 95% CI, 2.0-16.3). The median overall survival was 32.8 months (95% CI, 14.4 to not applicable). Tipifarnib-related hematologic AEs were manageable and included neutropenia (43.1%), thrombocytopenia (36.9%), and anemia (30.8%); other tipifarnib-related AEs included nausea (29.2%) and diarrhea (27.7%). One treatment-related death occurred. Mutations in RhoA, DNMT3A, and IDH2 were seen in 60%, 33%, and 27%, respectively, in the AITL tipifarnib responder group vs 36%, 9%, and 9% in the nonresponder group. Tipifarnib monotherapy demonstrated encouraging clinical activity in heavily pretreated relapsed/refractory PTCL, especially in AITL, with a manageable safety profile. This trial was registered at www.ClinicalTrials.gov as #NCT02464228.

Role of epigenetic in cancer biology, in hematologic malignancies and in anticancer therapy

Major epigenetic changes are associated with carcinogenesis, including aberrant DNA methylations and post-translational modifications of histone. Indeed evidence accumulated in recent years indicates that inactivating DNA hypermethylation preferentially targets the subset of polycomb group (PcG) genes that are regulators of developmental processes. Conversely, activating DNA hypomethylation targets oncogenic signaling pathway genes, but outcomes of both events lead in the overexpression of oncogenic signaling pathways that contribute to the stem-like state of cancer cells. On the basis of recent evidence from population-basedclinical and experimental studies, we hypothesize that factors associated with risk for developing a hematologic malignancy (HM), such as metabolic syndrome and chronic inflammation, may trigger epigenetic mechanisms to increase the transcriptional expression of oncogenes and activate oncogenic signaling pathways. Signaling pathways associated with such risk factors include but are not limited to pro-inflammatory nuclear factor κB (NF-κB) and mitogenic, growth, and survival Janus kinase (JAK) intracellular non-receptor tyrosine kinase-triggered pathways. The latter includes signaling pathways such as transducer and activator of transcription (STAT), Ras GTPases/mitogen-activated protein kinases (MAPKs)/extracellular signal-related kinases (ERKs), phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR), and β-catenin pathways. Recent findings on epigenetic mechanisms at work in the biology of cancer and in HMs and their importance in the etiology and pathogenesis of these diseases are herein summarized and discussed. Furthermore, the role of epigenetic processes in the determination of biological identity, the consequences for interindividual variability in disease clinical profile, and the potential of epigenetic drugs in HMs are also considered.

Histone modification in psoriasis: Molecular mechanisms and potential therapeutic targets

Psoriasis is an immune-mediated, inflammatory disease. Genetic and environmental elements are involved in the nosogenesis of this illness. Epigenetic inheritance serves as the connection between genetic and environmental factors. Histone modification, an epigenetic regulatory mechanism, is implicated in the development of numerous diseases. The basic function of histone modification is to regulate cellular functions by modifying gene expression. Modulation of histone modification, such as regulation of enzymes pertinent to histone modification, can be an alternative approach for treating some diseases, including psoriasis. Herein, we reviewed the regulatory mechanisms and biological effects of histone modifications and their roles in the pathogenesis of psoriasis.

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. In vitro 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.

Activation of Hypoxia Inducible Factor-1 Alpha-Mediated DNA Methylation Enzymes (DNMT3a and TET2) Under Hypoxic Conditions Regulates S100A6 Transcription to Promote Lung Cancer Cell Growth and Metastasis

Aims: This research was aimed at investigating the effects of hypoxia inducible factor-1 alpha (HIF-1α)-mediated DNA methylation enzymes (ten-eleven translocase-2 [TET2] and DNA methyltransferase-3a [DNMT3a]) under hypoxic conditions on S100A6 transcription, thereby promoting the growth and metastasis of lung cancer cells. Methods: The expression of HIF-1α or S100A6 in lung cancer cells was interfered with under normoxic and hypoxic conditions, and the cell proliferative, migratory, and invasive properties were assessed. The mechanism of HIF-1α-regulated TET2 and DNMT3 effects on S100A6 transcription under hypoxic conditions was further investigated. Results: Functionally, S100A6 over-expression promoted lung cancer cell proliferation and metastasis. S100A6 over-expression reversed the inhibitory effects of HIF-1α interference on the proliferation and metastasis of lung cancer cells. S100A6 was induced to express in an HIF-1α-dependent manner under hypoxic conditions, and silencing S100A6 or HIF-1α suppressed lung cancer cell proliferation and metastasis under hypoxic conditions. Further, The Cancer Genome Atlas-lung adenocarcinoma database analysis revealed that S100A6 mRNA levels had a negative correlation with methylation levels. Mechanistically, CpG hypomethylation status in the S100A6 promoter hypoxia response element had an association with HIF-1α induction. TET2 was enriched in S100A6 promoter region of lung cancer cells under hypoxic conditions, whereas DNMT3a enrichment was reduced in S100A6 promoter region. HIF-1α-mediated S100A6 activation was linked to DNMT3a-associated epigenetic inactivation and TET2 activation. Innovation: The activation of HIF-1α-mediated DNA methylation enzymes under hypoxic conditions regulated S100A6 transcription, thereby promoting lung cancer cell growth and metastasis. Conclusion: In lung cancer progression, hypoxia-induced factor HIF-1α combined with DNA methylation modifications co-regulates S100A6 transcriptional activation and promotes lung cancer cell growth and metastasis.

TP53 and KMT2D mutations associated with worse prognosis in peripheral T-cell lymphomas

There are limited studies on mutation profiling for Peripheral T-cell lymphomas (PTCL) in the Chinese population. We retrospectively analyzed the clinical and genetic landscape of 66 newly diagnosed Chinese patients. Targeted next-generation sequencing (NGS) was performed for tissues from these patients. At least one mutation was detected in 60 (90.9%) patients, with a median number of 3 (0-7) mutations, and 32 (48.5%) cases detected with more than 4 mutations. The genes with higher mutation frequencies were TET2, RHOA, DNMT3A, IDH2, TP53, STAT3, and KMT2D respectively. When mutant genes are classified by functional group, the most prevalent mutations are related to epigenetics and signal transduction. IPI ≥2, PIT ≥2, and failure to achieve partial remission (PR) were factors for inferior progression-free survival (PFS) and overall survival (OS). Multivariate analysis showed TP53 was an adverse factor for PFS (HR, 3.523; 95% CI, 1.262-9.835; p = 0.016), and KMT2D was an adverse factor for OS (HR, 10.097; 95% CI, 1.000-101.953; p = 0.048). Mutation profiling could help differentiate distinct types of PTCL and serve as a useful tool for determining treatment options and prognoses.

Epigenetic silencing of miR-125a-3p promotes the progress of human cholangiocarcinoma via increasing CAC1 expression

We aimed to investigate the dysregulation of the microRNAs(miRNAs) in cholangiocarcinoma (CCA), including its impact on the homeostasis of the transcriptome and cellular behavior. MiRNAs serve as potent epigenetic regulators of transcriptional output, targeting various signaling pathways. This study aimed to investigate the expression level, epigenetic mechanism and function of miR-125a-3 in CCA. The study data showed that the expression level of miR125a-3p was decreased in CCA tissue samples and cell lines, and it was closely related to lymph node metastasis, tissue differentiation and TNM stage. The data demonstrate a strong association between decreased miR-125a-3p expression and poorer prognosis in cholangiocarcinoma patients. miR-125a-3p acts as a tumor suppressor by inhibiting the viability, migration and invasion of CCA cells. There are CpG islands in the promoter region of miR-125a-3p gene, and the methylation of the promoter region of miR-125a-3p gene leads to the transcriptional repression of miR-125a-3p. In addition, miR125a-3p can target and regulate CAC1 mRNA and protein expression in the downstream mechanism, and the high expression of CAC1 can promote the proliferation, migration and invasion of cholangiocarcinoma cells. These data demonstrate that miR-125a-3p promoter methylation leads to silencing of its expression. Mechanically, miR-125a-3p acts as a tumor suppressor and participates in the occurrence and development of CCA through targeting CAC1 gene expression. Therefore, miR-125a-3p may serve as a new target for the diagnosis, prognostic assessment or molecular therapy of CCA.

Epigenetic Priming by Hypomethylation Enhances the Immunogenic Potential of Tolinapant in T-cell Lymphoma

Programmed cell death mechanisms are important for the regulation of tumor development and progression. Evasion of and resistance to apoptosis are significant factors in tumorigenesis and drug resistance. Bypassing apoptotic pathways and eliciting another form of regulated cell death, namely necroptosis, an immunogenic cell death (ICD), may override apoptotic resistance. Here, we present the mechanistic rationale for combining tolinapant, an antagonist of the inhibitor of apoptosis proteins (IAP), with decitabine, a hypomethylating agent (HMA), in T-cell lymphoma (TCL). Tolinapant treatment alone of TCL cells in vitro and in syngeneic in vivo models demonstrated that ICD markers can be upregulated, and we have shown that epigenetic priming with decitabine further enhances this effect. The clinical relevance of ICD markers was confirmed by the direct measurement of plasma proteins from patients with peripheral TCL treated with tolinapant. We showed increased levels of necroptosis in TCL lines, along with the expression of cancer-specific antigens (such as cancer testis antigens) and increases in genes involved in IFN signaling induced by HMA treatment, together deliver a strong adaptive immune response to the tumor. These results highlight the potential of a decitabine and tolinapant combination for TCL and could lead to clinical evaluation.

SIGNIFICANCE

The IAP antagonist tolinapant can induce necroptosis, a key immune-activating event, in TCL. Combination with DNA hypomethylation enhances tolinapant sensitivity and primes resistant cells by re-expressing necrosome proteins. In addition, this combination leads to increases in genes involved in IFN signaling and neoantigen expression, providing further molecular rationale for this novel therapeutic option.

Phase II study of the novel antifolate agent pralatrexate in combination with the histone deacetylase inhibitor romidepsin for the treatment of patients with mature T-cell lymphoma

Previously, we conducted a Phase I study of the combination of pralatrexate and romidepsin in patients with relapsed/refractory (R/R) lymphomas and subsequently conducted a multicenter Phase II study in patients with untreated or R/R mature T cell lymphomas (MTCL). Patients received pralatrexate 25 mg/m2 and romidepsin 12 mg/m2 every 2 weeks. Fourteen patients were evaluable for efficacy. Overall response rate was 35.7% with CR in 14.3% and disease control in 50%. The mDOR was 8.2 months, mPFS was 3.6 months, and mOS was 20.2 months. Gastrointestinal side effects were most common in up to 33%; there was only one hematologic toxicity of grade 3 anemia. Combining results of MTCL patients from the Phase I and II studies (N = 28), the ORR was 53.5% with CR in 21.4%, disease control in67.8%, and DOR of 7.2 months. The combination was safe however does not out-perform other combination strategies.Trial Registration: www.clinicaltrials.gov (NCT01947140).

Epigenetic dysregulation in cancers by isocitrate dehydrogenase 2 (IDH2)

Recent advances in genome-wide studies have revealed numerous epigenetic regulations brought about by genes involved in cellular metabolism. Isocitrate dehydrogenase (IDH), an essential enzyme, that converts isocitrate into -ketoglutarate (KG) predominantly in the tricarboxylic acid (TCA) cycle, has gained particular importance due to its cardinal role in the metabolic pathway in cells. IDH1, IDH2, and IDH3 are the three isomeric IDH enzymes that have been shown to regulate cellular metabolism. Of particular importance, IDH2 genes are associated with several cancers, including gliomas, oligodendroglioma, and astrocytomas. These mutations lead to the production of oncometabolite D-2-hydroxyglutarate (D-2-HG), which accumulates in cells promoting tumor growth. The enhanced levels of D-2-HG competitively inhibit α-KG dependent enzymes, inhibiting cell TCA cycle, upregulating the cell growth and survival relevant HIF-1α pathway, promoting DNA hypermethylation related epigenetic activity, all of which synergistically contribute to carcinogenesis. The present review discusses epigenetic mechanisms inIDH2 regulation in cells and further its clinical implications.

Primary pancreatic peripheral T-cell lymphoma: A case report

BACKGROUND

Primary pancreatic lymphoma (PPL) is an exceedingly rare tumor with limited mention in scientific literature. The clinical manifestations of PPL are often nonspecific, making it challenging to distinguish this disease from other pancreatic-related diseases. Chemotherapy remains the primary treatment for these individuals.

CASE SUMMARY

In this case study, we present the clinical details of a 62-year-old woman who initially presented with vomiting, abdominal pain, and dorsal pain. On further evaluation through positron emission tomography-computed tomography, the patient was considered to have a pancreatic head mass. However, subsequent endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) revealed that the patient had pancreatic peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS). There was a substantial decrease in the size of the pancreatic mass after the patient underwent a cycle of chemotherapy comprised of brentuximab vedotin, gemcitabine, and oxaliplatin (brentuximab vedotin and Gemox). The patient had significant improvement in radiological findings at the end of the first cycle.

CONCLUSION

Primary pancreatic PTCL-NOS is a malignant and heterogeneous lymphoma, in which the clinical manifestations are often nonspecific. It is difficult to diagnose, and the prognosis is poor. Imaging can only be used for auxiliary diagnosis of other diseases. With the help of immunostaining, EUS-FNA could be used to aid in the diagnosis of PPL. After a clear diagnosis, chemotherapy is still the first-line treatment for such patients, and surgical resection is not recommended. A large number of recent studies have shown that the CD30 antibody drug has potential as a therapy for several types of lymphoma. However, identifying new CD30-targeted therapies for different types of lymphoma is urgently needed. In the future, further research on antitumor therapy should be carried out to improve the survival prognosis of such patients.

Comprehensive genomic analysis reveals molecular heterogeneity in pediatric ALK-positive anaplastic large cell lymphoma

Anaplastic large cell lymphoma (ALCL) is a mature T-cell lymphoma that accounts for for 10-15% of childhood lymphomas. Despite the observation that more than 90% of pediatric cases harbor the anaplastic lymphoma kinase (ALK) rearrangement resulting in aberrant ALK kinase expression, there is significant clinical, morphologic, and biological heterogeneity. To gain insights into the genomic aberrations and molecular heterogeneity within ALK-positive ALCL(ALK+ ALCL), we analyzed 46 pediatric ALK+ ALCLs by whole-exome sequencing, RNA-sequencing, and DNA methylation profiling. Whole-exome sequencing found on average 25 SNV/Indel events per sample with recurring genetic events in regulators of DNA damage (TP53, MDM4), transcription (JUNB), and epigenetic regulators (TET1, KMT2B, KMT2A, KMT2C, KMT2E). Gene expression and methylation profiling consistently subclassified ALK+ ALCLs into two groups characterized by diferential ALK expression levels. The ALK-low group showed enrichment of pathways associated with immune response, cytokine signaling, and a hypermethylated predominant pattern compared to the ALK- high group, which had more frequent copy number changes, and was enriched with pathways associated with cell growth, proliferation, metabolic pathways, and. Taken together, these findings suggest that there is molecular heterogeneity within pediatric ALK+ALCL, predicting distinct biological mechanisms that may provide novel insights into disease pathogenesis and represent prognostic markers.

The RNA sequencing results revealed the expression of different genes and signaling pathways during chemotherapy resistance in peripheral T-cell lymphoma

BACKGROUND

Peripheral T-cell lymphoma (PTCL) is a subtype of non-Hodgkin's lymphoma that occurs primarily at extranodal sites and is commonly treated using chemotherapy and radiotherapy. PTCL is more malignant than other lymphoid tumors, resulting in a poor prognosis.The 5-year recurrence rate remains high, and there is a lack of standard treatment for patients with relapse-resistant disease. However, the molecular mechanisms underlying the resistance of peripheral T-cell lymphoma cells to chemotherapeutic drugs, as well as identifying strategies to overcome drug resistance remains unclear. In this study, we aimed to identify pivotal genes and signaling pathways associated with chemotherapy resistance in PTCL.

METHODS

In this study, a total of 5 healthy controls and 7 clinical patients were enrolled; 4 patients were classified as chemotherapy sensitive, and 3 patients were classified as chemotherapy resistant. Peripheral blood samples were collected from each participant, and total RNA was extracted from the white blood cells. RNA sequencing was conducted on the Illumina HiSeq platform to obtain comprehensive gene expression profiles. Subsequently, the expression patterns of the DEGs associated with the most enriched signaling pathways, with a special focus on cancer-related genes, were validated using quantitative real-time polymerase chain reaction (qRT-PCR) in peripheral TCL patients.

RESULTS

RNA sequencing (RNA-seq) analysis revealed 4063 differentially expressed genes (DEGs) in peripheral T-cell lymphoma specimens from patients with chemotherapy resistance, of which 1128 were upregulated and 2935 were downregulated. Subsequent quantitative gene expression analysis confirmed a differential expression pattern in all the libraries, with 9 downregulated genes and 10 upregulated genes validated through quantitative real-time PCR in 6 clinical specimens from patients with chemotherapy resistance. KEGG pathway analysis revealed significant alterations in several pathways, with 6 downregulated pathways and 9 upregulated pathways enriched in the DEGs. Notably, the TNF signaling pathway, which is extensively regulated, was among the pathways that exhibited significant changes. These findings suggest that DEGs and the TNF signaling pathway may play crucial roles in chemotherapy resistance in peripheral T-cell lymphoma.

CONCLUSION

Our study revealed that the expression of specific genes, including TNFRSF1B, TRADD2, and MAP3K7, may play an important role in chemotherapy resistance in peripheral T-cell lymphoma. Moreover, we identified the downregulation of the TNF signaling pathway, a crucial pathway involved in cell survival, death, and differentiation, as a potential contributor to the development of chemotherapy resistance in peripheral T-cell lymphoma. These findings provide valuable insights into the molecular mechanisms underlying chemotherapy resistance and highlight potential targets for overcoming treatment resistance in this challenging disease.

Circulating miR-129-3p in combination with clinical factors predicts vascular calcification in hemodialysis patients

Background

Vascular calcification (VC) commonly occurs and seriously increases the risk of cardiovascular events and mortality in patients with hemodialysis. For optimizing individual management, we will develop a diagnostic multivariable prediction model for evaluating the probability of VC.

Methods

The study was conducted in four steps. First, identification of miRNAs regulating osteogenic differentiation of vascular smooth muscle cells (VSMCs) in calcified condition. Second, observing the role of miR-129-3p on VC in vitro and the association between circulating miR-129-3p and VC in hemodialysis patients. Third, collecting all indicators related to VC as candidate variables, screening predictors from the candidate variables by Lasso regression, developing the prediction model by logistic regression and showing it as a nomogram in training cohort. Last, verifying predictive performance of the model in validation cohort.

Results

In cell experiments, miR-129-3p was found to attenuate vascular calcification, and in human, serum miR-129-3p exhibited a negative correlation with vascular calcification, suggesting that miR-129-3p could be one of the candidate predictor variables. Regression analysis demonstrated that miR-129-3p, age, dialysis duration and smoking were valid factors to establish the prediction model and nomogram for VC. The area under receiver operating characteristic curve of the model was 0.8698. The calibration curve showed that predicted probability of the model was in good agreement with actual probability and decision curve analysis indicated better net benefit of the model. Furthermore, internal validation through bootstrap process and external validation by another independent cohort confirmed the stability of the model.

Conclusion

We build a diagnostic prediction model and present it as an intuitive tool based on miR-129-3p and clinical indicators to evaluate the probability of VC in hemodialysis patients, facilitating risk stratification and effective decision, which may be of great importance for reducing the risk of serious cardiovascular events.

Genomic and transcriptomic profiling of peripheral T cell lymphoma reveals distinct molecular and microenvironment subtypes

Peripheral T cell lymphoma (PTCL) is a heterogeneous group of non-Hodgkin's lymphomas varying in clinical, phenotypic, and genetic features. The molecular pathogenesis and the role of the tumor microenvironment in PTCL are poorly understood, with limited biomarkers available for genetic subtyping and targeted therapies. Through an integrated genomic and transcriptomic study of 221 PTCL patients, we delineate the genetic landscape of PTCL, enabling molecular and microenvironment classification. According to the mutational status of RHOA, TET2, histone-modifying, and immune-related genes, PTCL is divided into 4 molecular subtypes with discrete patterns of gene expression, biological aberrations, and vulnerabilities to targeted agents. We also perform an unsupervised clustering on the microenvironment transcriptional signatures and categorize PTCL into 4 lymphoma microenvironment subtypes based on characteristic activation of oncogenic pathways and composition of immune communities. Our findings highlight the potential clinical rationale of future precision medicine strategies that target both molecular and microenvironment alterations in PTCL.

Epigenetics in Knee Osteoarthritis: A 2020-2023 Update Systematic Review

Osteoarthritis is a leading cause of disability in the world. The scientific literature highlights the critical importance of epigenetic regulatory effects, intertwined with biomechanical and biochemical peculiar conditions within each musculoskeletal district. While the contribution of genetic and epigenetic factors to knee OA is well-recognized, their precise role in disease management remains an area of active research. Such a field is particularly heterogeneous, calling for regular analysis and summarizing of the data that constantly emerge in the scientific literature, often sparse and scant of integration. The aim of this study was to systematically identify and synthesize all new evidence that emerged in human and animal model studies published between 2020 and 2023. This was necessary because, to the best of our knowledge, articles published before 2019 (and partly 2020) had already been included in systematic reviews that allowed to identify the ones concerning the knee joint. The review was carried out in accordance with Preferential Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Only peer-reviewed articles were considered for inclusion. A total of 40 studies were identified, showing promising results in terms either of biomarker identification, new insight in mechanism of action or potential therapeutic targets for knee OA. DNA methylation, histone modification and ncRNA were all mechanisms involved in epigenetic regulation of the knee. Most recent evidence suggests that epigenetics is a most promising field with the long-term goal of improving understanding and management of knee OA, but a variety of research approaches need greater consolidation.

Peripheral T-Cell Lymphoma, Not Otherwise Specified: Diagnosis and Therapeutic Approaches for the Advanced Practice Provider

T-cell lymphomas (TCLs) have a unique pathobiology, clinically aggressive course, and poor prognosis. Recently, there have been significant advances in understanding the molecular genetic alterations of TCLs through next-generation sequencing. This has led to the development of specific therapeutic molecules. This review aims to provide an up-to-date overview of the current therapeutic approaches for the subtype peripheral T-cell lymphoma, not otherwise specified.

SOHO State-of-the-Art Updates and Next Questions: Treatment for Newly Diagnosed Peripheral T-Cell Lymphomas

Although a rare subset of non-Hodgkin lymphomas, peripheral T-cell lymphomas (PTCL) account for a disproportionate proportion of patient mortality. Conventional therapies are derived from experience treating aggressive B-cell lymphomas and center around CHOP-based chemotherapy. However, due to the unique biology and diverse subtypes of PTCL, most patients fail to durably respond to this approach and 5-year survival is only 20% to 30%. There have been multiple attempts to improve outcomes for patients with PTCL. Among the more successful strategies are the use of consolidative autologous stem cell transplant, the augmentation of CHOP with etoposide (CHOEP), and the use of brentuximab vedotin in CD30-positive PTCL. Advances in the understanding of histology-specific biology has cultivated enthusiasm to evaluate hypomethylating agents, histone deacetylate inhibitors, and phosphoinositol-3-kinase inhibitors in the frontline setting. Improvements in monitoring disease response and prognostication including the use of cell-free DNA, mutational profiling, and interim PET/CT imaging are also on the horizon. For patients with acute T-cell leukemia/lymphoma, the use of mogamulizumab-based therapy in the frontline setting may lead to advances in care. The true impact of these new-era therapies will only be elucidated as clinical practices incorporate the rapidly changing evidence.

Exploring the potential of histone demethylase inhibition in multi-therapeutic approaches for cancer treatment

Histone demethylases play a critical role in gene transcription regulation and have been implicated in cancer. Numerous reports have highlighted the overexpression of histone demethylases, such as LSD1 and JmjC, in various malignant tumor tissues, identifying them as effective therapeutic targets for cancer treatment. Despite many histone demethylase inhibitors entering clinical trials, their clinical efficacy has been limited. Therefore, combination therapies based on histone demethylase inhibitors, along with other modulators like dual-acting inhibitors, have gained significant attention and made notable progress in recent years. In this review, we provide an overview of recent advances in drug discovery targeting histone demethylases, focusing specifically on drug combination therapy and histone demethylases-targeting dual inhibitors. We discuss the rational design, pharmacodynamics, pharmacokinetics, and clinical status of these approaches. Additionally, we summarize the co-crystal structures of LSD1 inhibitors and their target proteins as well as describe the corresponding binding interactions. Finally, we also provided the challenges and future directions for utilizing histone demethylases in cancer therapy, such as PROTACs and molecular glue etc.

Therapeutic challenges in peripheral T-cell lymphoma

Peripheral T-cell lymphoma (PTCL) is a rare and heterogeneous group of hematological malignancies. Compared to our knowledge of B-cell tumors, our understanding of T-cell leukemia and lymphoma remains less advanced, and a significant number of patients are diagnosed with advanced stages of the disease. Unfortunately, the development of drug resistance in tumors leads to relapsed or refractory peripheral T-Cell Lymphomas (r/r PTCL), resulting in highly unsatisfactory treatment outcomes for these patients. This review provides an overview of potential mechanisms contributing to PTCL treatment resistance, encompassing aspects such as tumor heterogeneity, tumor microenvironment, and abnormal signaling pathways in PTCL development. The existing drugs aimed at overcoming PTCL resistance and their potential resistance mechanisms are also discussed. Furthermore, a summary of ongoing clinical trials related to PTCL is presented, with the aim of aiding clinicians in making informed treatment decisions.

Phase Separation of Chromatin Structure-related Biomolecules: A Driving Force for Epigenetic Regulations

Intracellularly, membrane-less organelles are formed by spontaneous fusion and fission of macro-molecules in a process called phase separation, which plays an essential role in cellular activities. In certain disease states, such as cancers and neurodegenerative diseases, aberrant phase separations take place and participate in disease progression. Chromatin structure-related proteins, based on their characteristics and upon external stimuli, phase separate to exert functions like genome assembly, transcription regulation, and signal transduction. Moreover, many chromatin structure-related proteins, such as histones, histone-modifying enzymes, DNA-modifying enzymes, and DNA methylation binding proteins, are involved in epigenetic regulations through phase separation. This review introduces phase separation and how phase separation affects epigenetics with a focus on chromatin structure-related molecules.

Epigenetic Alterations That Are the Backbone of Immune Evasion in T-cell Malignancies

Epigenetic alterations are heritable and enduring modifications in gene expression that play a pivotal role in immune evasion. These include alterations to noncoding RNA, DNA methylation, and histone modifications. DNA methylation plays a crucial role in normal cell growth and development but alterations in methylation patterns such as hypermethylation or hypomethylation can enable tumor and viral cells to evade host immune responses. Histone modifications can also inhibit immune responses by promoting the expression of genes involved in suppressing normal immune function. In the case of T-cell lymphoma, adult T-cell lymphomas (ATL) also undergo immune evasion through the exceptional function of its accessory and regulatory genes. Epigenetic therapies are emerging as a promising adjunct to traditional immunotherapy and chemotherapy regimens. Clinical trials are currently investigating the use of epigenetic therapies in combination with immunotherapies and chemotherapies for more effective treatment of ATL and other cancers. This review highlights epigenetic alterations that are widely found in T-cell malignancies.

Impact of primary organ site of involvement by peripheral T-cell lymphoma not otherwise specified on survival

INTRODUCTION

Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) is a rare, highly heterogeneous group of mature T-cell neoplasms that historically has been associated with poor outcomes. We sought to investigate the influence of primary disease site on PTCL-NOS outcomes using a large national cancer registry.

METHODS

Baseline clinical and demographic data including primary organ of involvement and Ann Arbor disease stage were extracted from the SEER database. Patients were grouped into nine organ system groups and compared to nodal disease acting as a control. Cox regression models were utilized for adjusted survival analyses.

RESULTS

A total of 3095 patients were identified in the SEER database and included in the final analysis. The median age was 61 and a majority of patients were male (60%) and identified as non-Hispanic white (68%). A plurality of patients had stage IV disease (32%). Lymph nodes and spleen were the most common primary disease sites (67%), while central nervous system was the least common (1%). Patients with early-stage PTCL-NOS of the gastrointestinal/genitourinary systems had worse overall survival [HR = 1.97 (1.50-2.59); p < 0.001] and lymphoma-specific survival [HR = 1.74 (1.26-2.40); p < 0.001] which was statistically significant even after adjusting for other variables. Early-stage PTCL-NOS of the central nervous system also had worse overall survival [HR = 1.90 (1.11-3.27); p = 0.020] and lymphoma-specific survival [HR = 2.11 (1.17-3.80); p = 0.013]. Early-stage PTCL-NOS of the skin had better overall survival [HR = 0.54 (0.42-0.68); p < 0.001] and lymphoma-specific survival [HR = 0.388 (0.28-0.53); p < 0.001] which was statistically significant even after adjustments.

CONCLUSION

Our findings suggest an association between primary organ involved by PTCL-NOS and both overall and lymphoma-specific survival even after adjusting for common variables. These results warrant validation in future prospective studies.

Enhancing anti-tumor immune responses through combination therapies: epigenetic drugs and immune checkpoint inhibitors

Epigenetic mechanisms are processes that affect gene expression and cellular functions without involving changes in the DNA sequence. This abnormal or unstable expression of genes regulated by epigenetics can trigger cancer and other various diseases. The immune cells involved in anti-tumor responses and the immunogenicity of tumors may also be affected by epigenomic changes. This holds significant implications for the development and application of cancer immunotherapy, epigenetic therapy, and their combined treatments in the fight against cancer. We provide an overview of recent research literature focusing on how epigenomic changes in immune cells influence immune cell behavior and function, as well as the immunogenicity of cancer cells. And the combined utilization of epigenetic medications with immune checkpoint inhibitors that focus on immune checkpoint molecules [e.g., Programmed Death 1 (PD-1), Cytotoxic T-Lymphocyte-Associated Protein 4 (CTLA-4), T cell Immunoglobulin and Mucin Domain (TIM-3), Lymphocyte Activation Gene-3 (LAG-3)] present in immune cells and stromal cells associated with tumors. We highlight the potential of small-molecule inhibitors targeting epigenetic regulators to amplify anti-tumor immune responses. Moreover, we discuss how to leverage the intricate relationship between cancer epigenetics and cancer immunology to create treatment regimens that integrate epigenetic therapies with immunotherapies.

The Role of Epigenetic Modifier Mutations in Peripheral T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) are a group of diseases with a low incidence, high degree of heterogeneity, and a dismal prognosis in most cases. Because of the low incidence of these diseases, there have been few therapeutic novelties developed over time. Nevertheless, this fact is changing presently as epigenetic modifiers have been shown to be recurrently mutated in some types of PTCLs, especially in the cases of PTCLs not otherwise specified (PTCL-NOS), T follicular helper (TFH), and angioimmunoblastic T-cell lymphoma (AITL). These have brought about more insight into PTCL biology, especially in the case of PTCLs arising from TFH lymphocytes. From a biological perspective, it has been observed that ten-eleven translocators (TET2) mutated T lymphocytes tend to polarize to TFH, while Tregs lose their inhibitory properties. IDH2 R172 was shown to have inhibitory effects on TET2, mimicking the effects of TET2 mutations, as well as having effects on histone methylation. DNA methyltransferase 3A (DNMT3A) loss-of-function, although it was shown to have opposite effects to TET2 from an inflammatory perspective, was also shown to increase the number of T lymphocyte progenitors. Aside from bringing about more knowledge of PTCL biology, these mutations were shown to increase the sensitivity of PTCLs to certain epigenetic therapies, like hypomethylating agents (HMAs) and histone deacetylase inhibitors (HDACis). Thus, to answer the question from the title of this review: We found the Achilles heel, but only for one of the Achilles.

The roles of epigenetic regulation in cholangiocarcinogenesis

Cholangiocarcinoma (CCA), a heterogeneous malignancy of bile duct epithelial cells, is characterized by aggressiveness, difficult diagnosis, and poor prognosis due to limited understanding and lack of effective therapeutic strategies. Genetic and epigenetic alterations accumulated in CCA cells can cause the aberrant regulation of oncogenes and tumor suppressors. Epigenetic alterations with histone modification, DNA methylation, and noncoding RNA modulation are associated with the carcinogenesis of CCA. Mutation or silencing of genes by various mechanisms can be a frequent event during CCA development. Alterations in histone acetylation/deacetylation at the posttranslational level, DNA methylation at promoters, and noncoding RNA regulation contribute to the heterogeneity of CCA and drive tumor development. In this review article, we mainly focus on the roles of epigenetic regulation in cholangiocarcinogenesis. Alterations in epigenetic modification can be potential targets for the therapeutic management of CCA, and epigenetic targets may become diagnostic biomarkers of CCA.

Updates in pathobiological aspects of anaplastic large cell lymphoma

Anaplastic large cell lymphomas (ALCL) encompass several distinct subtypes of mature T-cell neoplasms that are unified by the expression of CD30 and anaplastic cytomorphology. Identification of the cytogenetic abnormality t(2;5)(p23;q35) led to the subclassification of ALCLs into ALK+ ALCL and ALK- ALCL. According to the most recent World Health Organization (WHO) Classification of Haematolymphoid Tumours as well as the International Consensus Classification (ICC) of Mature Lymphoid Neoplasms, ALCLs encompass ALK+ ALCL, ALK- ALCL, and breast implant-associated ALCL (BI-ALCL). Approximately 80% of systemic ALCLs harbor rearrangement of ALK, with NPM1 being the most common partner gene, although many other fusion partner genes have been identified to date. ALK- ALCLs represent a heterogeneous group of lymphomas with distinct clinical, immunophenotypic, and genetic features. A subset harbor recurrent rearrangement of genes, including TYK2, DUSP22, and TP63, with a proportion for which genetic aberrations have yet to be characterized. Although primary cutaneous ALCL (pc-ALCL) is currently classified as a subtype of primary cutaneous T-cell lymphoma, due to the large anaplastic and pleomorphic morphology together with CD30 expression in the malignant cells, this review also discusses the pathobiological features of this disease entity. Genomic and proteomic studies have contributed significant knowledge elucidating novel signaling pathways that are implicated in ALCL pathogenesis and represent candidate targets of therapeutic interventions. This review aims to offer perspectives on recent insights regarding the pathobiological and genetic features of ALCL.

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.

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.

Roles and regulatory mechanisms of KIN17 in cancers (Review)

KIN17, which is known as a DNA and RNA binding protein, is highly expressed in numerous types of human cancers and was discovered to participate in several vital cell behaviors, including DNA replication, damage repair, regulation of cell cycle and RNA processing. Furthermore, KIN17 is associated with cancer cell proliferation, migration, invasion and cell cycle regulation by regulating pathways including the p38 MAPK, NF-κB-Snail and TGF-β/Smad2 signaling pathways. In addition, knockdown of KIN17 was found to enhance the sensitivity of tumor cells to chemotherapeutic agents. Immunohistochemical analysis revealed that there were significant differences in the expression of KIN17 between cancer tissues and adjacent tissues. Both the Kaplan-Meier survival analysis and multivariate Cox regression analysis indicated that KIN17 is aberrantly high expressed in various tumor tissues and is also associated with poor prognosis in patients with various tumor types. Taken together, KIN17 has key roles in tumorigenesis and cancer development. Investigating the relationship between KIN17 and neoplasms will provide a vital theoretical basis for KIN17 to serve as a diagnostic and prognostic biomarker for cancer patients and as a potential target for cancer therapy.

Epigenetic Alterations in Canine Malignant Lymphoma: Future and Clinical Outcomes

Canine malignant lymphoma is a common neoplasia in dogs, and some studies have used dogs as a research model for molecular mechanisms of lymphomas in humans. In two species, chemotherapy is the treatment of choice, but the resistance to conventional anticancer drugs is frequent. The knowledge of molecular mechanisms of development and progression of neoplasia has expanded in recent years, and the underlying epigenetic mechanisms are increasingly well known. These studies open up new ways of discovering therapeutic biomarkers. Histone deacetylases and demethylase inhibitors could be a future treatment for canine lymphoma, and the use of microRNAs as diagnosis and prognosis biomarkers is getting closer. This review summarises the epigenetic mechanisms underlying canine lymphoma and their possible application as treatment and biomarkers, both prognostic and diagnostic.

Protein arginine methyltransferase 1 upregulates matrix metalloproteinase-2/9 expression via Zeste Homolog 2 to promote human rheumatoid arthritis fibroblast-like synovial cell survival and metastasis

OBJECTIVE

To explore the role of protein arginine methyltransferase 1 (PRMT1) in the development of rheumatoid arthritis (RA).

METHODS

Fibroblast-like synoviocytes (FLS) were isolated from synovial tissues, cultured and transfected with plasmid vector or short hairpin RNA (shRNA). The morphology and surface markers of FLS were investigated by light microscopy and flow cytometry. The expression levels of PRMT1, Zeste Homolog 2 (EZH2), matrix metalloproteinase-2 (MMP-2) and MMP-9 were detected by real-time polymerase chain reaction and Western blotting. Cell viability was tested by MTT assay, cell proliferation was assessed by EdU assay, cell invasion was evaluated by Transwell invasion test, cell migration was detected by wound healing assay, and cell apoptosis was detected by flow cytometry.

RESULTS

The expression of PRMT1 was elevated in RA synovial tissues compared with control tissues. FLS from control tissues showed a lower level of PRMT1 than FLS from RA tissues, and FLS from RA tissues had a stronger ability of cell survival and metastasis than those from control tissues. When silencing PRMT1 expression, FLS from RA tissues showed a decreased ability of cell survival and metastasis. Additionally, FLS from RA tissues expressed a higher level of MMP-2 and MMP-9. When silencing PRMT1 expression, the expression of MMP-2 and MMP-9 of FLS was suppressed. Furthermore, the effect of PRMT1 on FLS was mediated by EZH2.

CONCLUSION

We found that PRMT1 had an overall effect on FLS via EZH2, which contributed to the development of RA. Hence, PRMT1 and EZH2 provide potential targets for RA treatment.

Tumor mutation burden involving epigenetic regulatory genes and the RhoA GTPase predicts overall survival in nodal mature T-cell lymphomas

Nodal mature T-cell lymphomas (nMTCL) comprises a heterogeneous group of rare malignancies with aggressive biological behavior and poor prognosis. Epigenetic phenomena, including mutations in genes that control DNA methylation and histone deacetylation, in addition to inactivating mutations in the RhoA GTPase, play a central role in its pathogenesis and constitute potential new targets for therapeutic intervention. Tumor mutational burden (TMB) reflects the process of clonal evolution, predicts response to anti-cancer therapies and has emerged as a prognostic biomarker in several solid neoplasms; however, its potential prognostic impact remains unknown in nMTCL. In this study, we conducted Sanger sequencing of formalin-fixed paraffin-embedded (FFPE) diagnostic tumor samples using a target-panel to search for recurrent mutations involving the IDH-1/IDH-2, TET-2, DNMT3A and RhoA genes in 59 cases of nMTCL. For the first time, we demonstrated that high-TMB, defined by the presence of ≥ two mutations involving the aforementioned genes, was associated with decreased overall survival in nMTCL patients treated with CHOP-like regimens. Additionally, high-TMB was correlated with bulky disease, lower overall response rate, and higher mortality. Future studies using larger cohorts may validate our preliminary results that indicate TMB as a potential molecular biomarker associated with adverse prognosis in nMTCL.

Pancancer Analysis of the Prognostic and Immunotherapeutic Value of Progestin and AdipoQ Receptor 4

AdipoQ receptor 4 (PAQR4) belongs to the family of progestin and AdipoQ receptors. PAQR4 plays an oncogenic role in lung and breast cancer. However, systematic pancancer analyses of PAQR4 have not been performed. The purpose was to investigate the prognostic and immunological significance of PAQR4 across 31 tumor types. Data were obtained from the following sources: TCGA, GEO, UALCAN, TIMER, GEPIA2, KM plotter, and TISIDB databases. The results proved that PAQR4 expression was significantly elevatory in most cancer types. We then explored the utility of PAQR4 as a prognostic indicator across all cancers. Using Cox proportional risk regression models, it has been demonstrated that PAQR4 is an independent risk factor in. High PAQR4 expression was not associated with other prognostic indicators, including overall survival, disease-free interval, disease-specific survival, and progression-free period. Subsequently, we explored the immunological value of PAQR4 and found that PAQR4 expression significantly correlated with tumor mutational burden, microsatellite instability, neoantigen, and immune checkpoint genes in tumors. It also significantly negatively correlated with most tumors' ESTIMATE scores, indicating that PAQR4 can influence the cellular composition of the tumor microenvironment. Our findings suggest the immunotherapeutic potential of PAQR4 in tumors. Finally, we explored the role of PAQR4 in tumor drug resistance and found that PAQR4 expression affected the sensitivity to multiple chemotherapeutic agents. A significant role for PAQR4 in tumor immunity is evident in these studies, as well as its potential role in cancer diagnosis, prognosis, and treatment precision.

Types of T-cell lymphoma-a cytogenetic perspective

T cell lymphoma, a type of non-Hodgkin lymphomas is a rare form of malignancy with poor outcomes. TCLS are a heterogeneous group of lymphoid malignancies that occur in nodal and extranodal sites. There are two main types of TCLs namely T-lymphoblastic lymphoma/leukemia and Peripheral T-cell lymphomas classified based on clinical manifestations and cytogenetic mutations. The use of advance technology like karyotyping, fluorescent in situ hybridization (FISH), comparative genomic hybridization (CGH) has allowed us to study TCLs in detail and to observe a different biochemical change that occurs in different TCLs allowing us to classify and treat them differently. This review focuses on the different mutations occurring in different TCLs and how they help us distinguish one type from another.

FOXP family DNA methylation correlates with immune infiltration and prognostic value in NSCLC

Background: Forkhead box P (FOXP) family was introduced as a double-edged sword in tumorigenesis and influenced immunotherapy response by modulating host immunity. This study aimed to summarize the involvement of the FOXP family in non-small cell lung cancer (NSCLC).

Methods: The UALCAN, Gene Expression Profiling Interactive Analysis (GEPIA), and Reverse transcription-quantitative polymerase chain reaction (RT‒qPCR) were used to analyse the expression levels of the FOXP family in NSCLC. The prognostic impact was evaluated using Kaplan-Meier Plotter. MethSurv, UALCAN, and cBioPortal were applied to analyse the DNA methylation and mutation status of the FOXP family respectively. COEXPEDIA, STRING, and GeneMANIA were used to explore the interaction mechanism. Finally, TISIDB was used to investigate all of the immune-related characteristics regulated by the FOXP family.

Results: The expression levels of FOXP1/3/4 were dysregulated in NSCLC tissues than that in normal tissues. Groups with low expression levels of FOXP1/4 and high expression levels of FOXP2/3 were associated with poor prognosis in NSCLC. The transcriptional levels of FOXP2/3/4 were correlated with DNA methylation in NSCLC. FOXP1/3/4 DNA methylation were correlated with prognosis. Pathway enrichment analysis indicated the FOXP family was mainly related to immune-related pathways. After DNA methylation, the correlations between FOXP family and immune factors were opposite to that before alteration in NSCLC.

Conclusion: This study elucidated FOXP family could serve as vital diagnostic and prognostic biomarkers in NSCLC. Our study highlighted novel potential functions of FOXP family DNA methylation in regulation of immune-related signatures in NSCLC.

TET-2 mutations predict poor outcomes and are associated with unfavorable clinical-biological features in PTCL, not otherwise specified and angioimmunoblastic T-cell lymphoma in Brazilian patients

INTRODUCTION

Nodal peripheral T-cell lymphomas [nPTCL] constitute a heterogeneous group of rare malignancies with aggressive biological behavior and poor prognosis. Epigenetic phenomena involving genes that control DNA-methylation and histone deacetylation play a central role in their pathogenesis. However, the mutational landscape involving epigenetic regulators has never been reported in Latin American patients and their prognostic impact remains controversial.

PATIENTS AND METHODS

From 2000 to 2019, 59-Brazilian patients with nPTCL were eligible for screening mutations in the IDH-1, IDH-2, RHOA, TET-2 and DNMT3A genes by Sanger sequencing at Formalin-Fixed Paraffin-Embedded samples [FFPE] of diagnosis. We reported the frequency, distribution and potential prognosis of these mutations.

RESULTS

With a median follow-up of 3.70 years, estimate 2-year OS and PFS were 57.1% and 49.2%, respectively. Mutations in the IDH-1 gene were not found, mutations in the IDH-2 occurred in 3.4% (2/59), RHOA in 23.7% (14/59), TET-2 in 50.8% (30/59) and DNMT3A in 62.7% (37/59). RHOA gene mutations were more frequent in PTCL, NOS and AITL (p= 0.06). Almost half of the patients had more than one mutation in concomitance, particularly RHOA-mut and TET-2-mut. Mutations in RHOA (p= 0.030) and TET-2 (p= 0.046) were associated with high-tumor burden. In the non-ALCL subgroup (PTCL, NOS and AITL) TET-2 mutations were associated with decreased 2-year PFS [HR: 2.22, p= 0.048]. Likewise with lower overall response rate [ORR] (p= 0.048) and unfavorable clinical features, as bulky disease (p= 0.012), ECOG ⩾ 2 (p= 0.032), B-symptoms (p= 0.012), ⩾ 2 extranodal sites compromised (p= 0.022) and high-risk Prognostic Index for T-cell lymphoma (p= 0.005).

CONCLUSION

Mutations in RHOA, TET-2 and DNMT3A were frequent in Brazilian patients with nPTCL. TET-2 mutations were associated with lower ORR for CHOP-like chemotherapy, decreased PFS and unfavorable clinical-biological characteristics in non-ALCL (PTCL, NOS and AITL). Further studies using a larger cohort may validate our findings.

Simultaneous Analysis of the p16 Gene and Protein in Canine Lymphoma Cells and Their Correlation with pRb Phosphorylation

Simple Summary

Lymphoma is one of the most frequently diagnosed malignancies in dogs. The most common epigenetic alteration is gene methylation. Methylation of the p16 gene leads to decreased expression of its protein. The p16 protein inhibits the activity of cyclin-dependent kinase, as a negative control of the cell cycle to prevent phosphorylation of the retinoblastoma (pRb) protein. The methylation of the p16 gene has been reported in canine lymphomas, however, p16 protein expression has not been examined in previous studies. In this study, the gene and protein expression of p16, and phosphorylation of pRb, were examined simultaneously in canine lymphoma/leukemia cell lines treated with or without a demethylation drug in vitro. We identified the hypermethylation of the p16 gene, the decreased expression of p16 protein and the hyperphosphorylation of pRb in four out of eight cell lines. Furthermore, we revealed that the expression of the p16 protein was more stable than that of the p16 gene and more closely related to the phosphorylation of pRb. In conclusion, the p16 protein expression is suggested as a promising biomarker for canine lymphoma cells, and the p16–pRb pathway could be a target for the better treatment of canine lymphomas.

Abstract

Cyclin-dependent kinase inhibitor p16 (CDKN2A) primarily functions as a negative regulator of the retinoblastoma protein (pRb) pathway to prevent pRb phosphorylation, thus playing a critical role in cell cycle arrest. In canine lymphoma cells, methylation due to inactivation of the p16 gene has been reported. However, its protein expression has not been examined in previous studies. In our in vitro study, the gene and protein expression of p16 and phosphorylated pRb were examined simultaneously in eight canine lymphoma and leukemia cell lines (17-71, CLBL-1, GL-1, CLC, CLGL-90, Ema, Nody-1, and UL-1). Methylation of the p16 gene was also explored using the demethylation drug 5-Aza-2′-deoxycytidine (5-Aza). After 5-Aza treatment, p16 gene and protein expression increased and pRb phosphorylation decreased, suggesting that both hypermethylation of the p16 gene and pRb hyperphosphorylation occurred in four out of eight cell lines (CLBL-1, CLC, Nody-1, and UL-1). Moreover, the estimation of p16’s protein expression was better than that of p16’s mRNA expression because the expression of the protein was more stable than those of the gene, and highly related to the phosphorylation of pRb. These results revealed that p16’s protein expression could be a promising biomarker for canine lymphoma cells.

Non-Coding RNAs: New Dawn for Diabetes Mellitus Induced Erectile Dysfunction

Erectile dysfunction (ED) is a common sexual dysfunction in males, with multifactorial alterations which consist of psychological and organic. Diabetes mellitus (DM) induced erectile dysfunction (DMED) is a disconcerting and critical complication of DM, and remarkably different from non-diabetic ED. The response rate of phosphodiesterase type 5 inhibitor (PDE5i), a milestone for ED therapy, is far from satisfactory in DMED. Unfortunately, the contributing mechanisms of DMED remains vague. Hence, It is urgent to seek for novel prospective biomarkers or targets of DMED. Numerous studies have proved that non-coding RNAs (ncRNAs) play essential roles in the pathogenesis process of DM, which comprise of long non-coding RNAs (lncRNAs) and small non-coding RNAs (sncRNAs) like microRNAs (miRNAs), PIWI-interacting RNAs (piRNAs) and circular RNAs (circRNAs). However, the implications of ncRNAs in DMED are still understudied. This review highlights the pathophysiology of DMED, summarizes identified mechanisms of ncRNAs associated with DMED and covers the topic of perspectives for ncRNAs in DMED.

Recent Advances in the Management of Relapsed and Refractory Peripheral T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) are a group of heterogeneous lymphomas with poor overall prognosis, particularly in the setting of relapsed/refractory PTCL. Given the limited efficacy of current therapies, several different novel therapies encompassing multiple different mechanisms of action have been evaluated for relapsed and refractory PTCLs. In this review, we explore the current standard of care for relapsed/refractory PTCL, and evaluate in depth novel and emerging therapies, their scientific basis, and current trials for relapsed/refractory PTCL.