Targeting the JAK/STAT Pathway in T Cell Lymphoproliferative Disorders

The JAK-STAT signaling-related signature serves as a prognostic and predictive biomarker for renal cell carcinoma immunotherapy

Renal cell carcinoma (RCC) represents a significant portion of genitourinary cancers, marked by challenging prognosis and high metastasis rates. Immunotherapy has been applied in managing advanced renal cell carcinoma, but the therapeutic outcomes are unsatisfactory. In this study, we order to construct a Janus kinase/signal transduction and activator transcriptional (JAK/STAT)-related signature linked to kidney patient outcomes for better predicting the efficacy to immune checkpoint inhibitors (ICIs) and to provide guidance for effective combination therapy. We screened 25 differentially expressed genes (DEGs) that exhibited high expression in RCC samples and were enriched in the JAK-STAT signaling pathway. Among these genes, 11 key genes were identified and correlated with the expectation of Kidney Clear Cell Carcinoma (KIRC) patients and all these genes was significantly elevated in RCC tumor tissues and cancer cells compared to para-cancer tissues and normal renal cells. Utilizing these 11 genes, we divided RCC patients into high-risk and low-risk groups. We found a clear correlation between the clinicopathologic factors of KIRC patients and the JAK-STAT-related risk score. And the IHC results shown that the JAK3 and STAT4 expression of tumor was significantly higher than normal tissue in RCC patients, the level of JAK3 and STAT4 was positively related to the T stage of RCC patients. In addition, high-risk patients had a poorer prognosis and greater protumor immune cell infiltration, and benefitted less from immunotherapy than did low-risk patients. Furthermore, the JAK-STAT-related risk score can predict disease-free survival (DFS) in RCC patients according to the nomogram, which constructed in combination with other clinical features such as age, TNM-staging and stage. Our study demonstrated the JAK-STAT signaling pathway's important regulatory function in RCC tumor immunity. This insight not only enhances our ability to accurately predict the survival rate of RCC patients, but also underscores a potential therapeutic alternative for RCC, involving the combined targeting of the JAK-STAT pathway and immune checkpoints.

Inflammation as a driver of hematological malignancies

Hematopoiesis is a tightly regulated process that produces all adult blood cells and immune cells from multipotent hematopoietic stem cells (HSCs). HSCs usually remain quiescent, and in the presence of external stimuli like infection or inflammation, they undergo division and differentiation as a compensatory mechanism. Normal hematopoiesis is impacted by systemic inflammation, which causes HSCs to transition from quiescence to emergency myelopoiesis. At the molecular level, inflammatory cytokine signaling molecules such as tumor necrosis factor (TNF), interferons, interleukins, and toll-like receptors can all cause HSCs to multiply directly. These cytokines actively encourage HSC activation, proliferation, and differentiation during inflammation, which results in the generation and activation of immune cells required to combat acute injury. The bone marrow niche provides numerous soluble and stromal cell signals, which are essential for maintaining normal homeostasis and output of the bone marrow cells. Inflammatory signals also impact this bone marrow microenvironment called the HSC niche to regulate the inflammatory-induced hematopoiesis. Continuous pro-inflammatory cytokine and chemokine activation can have detrimental effects on the hematopoietic system, which can lead to cancer development, HSC depletion, and bone marrow failure. Reactive oxygen species (ROS), which damage DNA and ultimately lead to the transformation of HSCs into cancerous cells, are produced due to chronic inflammation. The biological elements of the HSC niche produce pro-inflammatory cytokines that cause clonal growth and the development of leukemic stem cells (LSCs) in hematological malignancies. The processes underlying how inflammation affects hematological malignancies are still not fully understood. In this review, we emphasize the effects of inflammation on normal hematopoiesis, the part it plays in the development and progression of hematological malignancies, and potential therapeutic applications for targeting these pathways for therapy in hematological malignancies.

Janus Kinase-Signal Transducer and Activator of Transcription Inhibitors for the Treatment and Management of Cancer

According to the World Health Organization (WHO), cancer is the second-highest cause of mortality worldwide, killing nearly 9.6 million people annually. Despite the advances in diagnosis and treatment during the last couple of decades, it remains a serious concern due to the limitations of currently available cancer management strategies. Therefore, alternative strategies are highly required to overcome these glitches. In addition, many etiological factors such as environmental and genetic factors initiate the activation of the Janus kinase (JAK)-signal transducer and activator of the transcription (STAT) pathway. This aberrant activation of the JAK-STAT pathway has been reported in various disease states, including inflammatory conditions, hematologic malignancies, and cancer. For instance, many patients with myeloproliferative neoplasms carry the acquired gain-of-function JAK2 V617F somatic mutation. This knowledge has dramatically improved our understanding of pathogenesis and has facilitated the development of therapeutics capable of suppressing the constitutive activation of the JAK-STAT pathway. Our aim is not to be expansive but to highlight emerging ideas towards preventive therapy in a modern view of JAK-STAT inhibitors. A series of agents with different specificities against different members of the JAK family of proteins is currently undergoing evaluation in clinical trials. Here we give a summary of how JAK-STAT inhibitors function and a detailed review of current clinical drugs for managing cancer as a new therapeutic approach.

Extranodal T- and NK-cell lymphomas

Non-cutaneous extranodal NK/T cell lymphoproliferations constitute a heterogenous group of rare neoplasms, occurring primarily in the gastro-intestinal tract, nasal area, spleen, and liver. Their nomenclature refers to their usual clinical presentation and predilection for specific anatomic sites-i.e. extranodal NK/T-cell lymphoma, nasal-type, hepatosplenic T-cell lymphoma, primary intestinal T-cell lymphomas, indolent lymphoproliferative disorders of the gastrointestinal tract, and breast implant-associated anaplastic large cell lymphoma. Extranodal tissues may also be involved by T-cell leukemias, or other entities usually presenting as nodal diseases. Primary extranodal entities range from indolent to highly aggressive diseases. Here, we will review the clinicopathologic features of the pertinent entities including the recent advances in their molecular and genetic characterization, with an emphasis on the changes introduced in the 2022 International Consensus Classification of lymphoid neoplasms, and highlight the diagnostic criteria helpful to sort out the distinction with potential mimickers.

Multiomics to investigate the mechanisms contributing to repression of PTPRC and SOCS2 in pediatric T-ALL: Focus on miR-363-3p and promoter methylation

T-cell acute lymphoblastic leukemia (T-ALL) is a heterogeneous and aggressive malignancy arising from T-cell precursors. MiRNAs are implicated in negative regulation of gene expression and when aberrantly expressed contribute to various cancer types, including T-ALL. Previously we demonstrated the oncogenic potential of miR-363-3p overexpression in a subgroup of T-ALL patients. Here, using combined proteomic and transcriptomic approaches, we show that miR-363-3p enhances cell growth of T-ALL in vitro via inhibition of PTPRC and SOCS2, which are implicated in repression of the JAK-STAT pathway. We propose that overexpression of miR-363-3p is a novel mechanism potentially contributing to overactivation of JAK-STAT pathway. Additionally, by combining the transcriptomic and methylation data of T-ALL patients, we show that promoter methylation may also contribute to downregulation of SOCS2 expression and thus potentially to JAK-STAT activation. In conclusion, we highlight aberrant miRNA expression and aberrant promoter methylation as mechanisms, alternative to mutations of JAK-STAT-related genes, which might lead to the upregulation of JAK-dependent signaling in T-ALL.

JAK/STAT Signaling: Molecular Targets, Therapeutic Opportunities, and Limitations of Targeted Inhibitions in Solid Malignancies

JAK/STAT signaling pathway is one of the important regulatory signaling cascades for the myriad of cellular processes initiated by various types of ligands such as growth factors, hormones, and cytokines. The physiological processes regulated by JAK/STAT signaling are immune regulation, cell proliferation, cell survival, apoptosis and hematopoiesis of myeloid and non-myeloid cells. Dysregulation of JAK/STAT signaling is reported in various immunological disorders, hematological and other solid malignancies through various oncogenic activation mutations in receptors, downstream mediators, and associated transcriptional factors such as STATs. STATs typically have a dual role when explored in the context of cancer. While several members of the STAT family are involved in malignancies, however, a few members which include STAT3 and STAT5 are linked to tumor initiation and progression. Other STAT members such as STAT1 and STAT2 are pivotal for antitumor defense and maintenance of an effective and long-term immune response through evolutionarily conserved programs. The effects of JAK/STAT signaling and the persistent activation of STATs in tumor cell survival; proliferation and invasion have made the JAK/STAT pathway an ideal target for drug development and cancer therapy. Therefore, understanding the intricate JAK/STAT signaling in the pathogenesis of solid malignancies needs extensive research. A better understanding of the functionally redundant roles of JAKs and STATs may provide a rationale for improving existing cancer therapies which have deleterious effects on normal cells and to identifying novel targets for therapeutic intervention in solid malignancies.

Identification of serum and glucocorticoid-regulated kinase 1 as a regulator of signal transducer and activator of transcription 3 signaling

Signal transducer and activator of transcription 3 (STAT3) plays key roles in cancer cell proliferation, invasion, and immunosuppression. In many human cancer cells, STAT3 is hyperactivated, which leads to tumor progression and drug resistance, and therefore STAT3 and its modulators are considered effective drug targets. However, the complex regulatory mechanisms of STAT3 have made it difficult to develop potent anticancer drugs that suppress its activity. Here, we report serum and glucocorticoid-regulated kinase 1 (SGK1) as a novel regulator of STAT3 signaling and an effective target for combination therapy with Janus kinase (JAK) inhibitors. We screened small molecules using a gain-of-function mutant of STAT3 resistant to JAK inhibition and found that an SGK1 inhibitor suppressed the constitutive activation of STAT3. Importantly, our results revealed that SGK1 also mediated the activation of wild-type STAT3. Further examination suggested that the tuberous sclerosis complex 2 and mammalian target of rapamycin signaling pathway were involved in STAT3 activation by SGK1. Finally, we demonstrated that SGK1 inhibition enhanced the inhibitory effect of a JAK inhibitor on STAT3 phosphorylation and cancer cell proliferation. Our findings provide new insights into the molecular mechanisms of STAT3 activation and suggest SGK1 as a potential target for STAT3-targeted combination cancer therapy.

Untwining Anti-Tumor and Immunosuppressive Effects of JAK Inhibitors-A Strategy for Hematological Malignancies?

Simple Summary

The Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway is aberrantly activated in many malignancies. Inhibition of this pathway via JAK inhibitors (JAKinibs) is therefore an attractive therapeutic strategy underlined by Ruxolitinib (JAK1/2 inhibitor) being approved for the treatment of myeloproliferative neoplasms. As a consequence of the crucial role of the JAK-STAT pathway in the regulation of immune responses, inhibition of JAKs suppresses the immune system. This review article provides a thorough overview of the current knowledge on JAKinibs’ effects on immune cells in the context of hematological malignancies. We also discuss the potential use of JAKinibs for the treatment of diseases in which lymphocytes are the source of the malignancy.

Abstract

The Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway propagates signals from a variety of cytokines, contributing to cellular responses in health and disease. Gain of function mutations in JAKs or STATs are associated with malignancies, with JAK2^V617F being the main driver mutation in myeloproliferative neoplasms (MPN). Therefore, inhibition of this pathway is an attractive therapeutic strategy for different types of cancer. Numerous JAK inhibitors (JAKinibs) have entered clinical trials, including the JAK1/2 inhibitor Ruxolitinib approved for the treatment of MPN. Importantly, loss of function mutations in JAK-STAT members are a cause of immune suppression or deficiencies. MPN patients undergoing Ruxolitinib treatment are more susceptible to infections and secondary malignancies. This highlights the suppressive effects of JAKinibs on immune responses, which renders them successful in the treatment of autoimmune diseases but potentially detrimental for cancer patients. Here, we review the current knowledge on the effects of JAKinibs on immune cells in the context of hematological malignancies. Furthermore, we discuss the potential use of JAKinibs for the treatment of diseases in which lymphocytes are the source of malignancies. In summary, this review underlines the necessity of a robust immune profiling to provide the best benefit for JAKinib-treated patients.

Treatment of canine cutaneous epitheliotropic T-cell lymphoma with oclacitinib: a case report

Canine cutaneous epitheliotropic T-cell lymphoma (CETL) is associated with a poor prognosis and without consistently beneficial treatment options. This case report describes a 9-year-old Staffordshire bull terrier with CETL treated with oclacitinib (0.7 mg/kg twice daily), resulting in partial remission that was maintained for three months. Further studies are warranted.

The Role of IL-35 in the Pathophysiological Processes of Liver Disease

It is known that liver diseases have several characteristics of massive lipid accumulation and lipid metabolic disorder, and are divided into liver inflammation, liver fibrosis, liver cirrhosis (LC), and hepatocellular carcinoma (HCC) in patients. Interleukin (IL)-35, a new-discovered cytokine, can protect the liver from the environmental attack by increasing the ratio of Tregs (T regulatory cells) which can increase the anti-inflammatory cytokines and inhibit the proliferation of immune cellular. Interestingly, two opposite mechanisms (pro-inflammatory and anti-inflammatory) have connection with the ultimate formation of liver diseases, which suggest that IL-35 may play crucial function in the process of liver diseases through immunosuppressive regulation. Besides, some obvious advantages also imply that IL-35 can be considered as a new therapeutic target to control the progression of liver diseases, while its mechanism of function still needs further research.

Recent advances upper gastrointestinal lymphomas: molecular updates and diagnostic implications

Approximately one-third of extranodal non-Hodgkin lymphomas involve the gastrointestinal (GI) tract, with the vast majority being diagnosed in the stomach, duodenum, or proximal small intestine. A few entities, especially diffuse large B-cell lymphoma and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue, represent the majority of cases. In addition, there are diseases specific to or characteristic of the GI tract, and any type of systemic lymphoma can present in or disseminate to these organs. The recent advances in the genetic and molecular characterisation of lymphoid neoplasms have translated into notable changes in the classification of primary GI T-cell neoplasms and the recommended diagnostic approach to aggressive B-cell tumours. In many instances, diagnoses rely on morphology and immunophenotype, but there is an increasing need to incorporate molecular genetic markers. Moreover, it is also important to take into consideration the endoscopic and clinical presentations. This review gives an update on the most recent developments in the pathology and molecular pathology of upper GI lymphoproliferative diseases.

A Network Pharmacology Approach to Explore the Mechanisms of Shugan Jianpi Formula in Liver Fibrosis

Purpose

We explored the mechanism of Shugan Jianpi Formula (SGJPF) and its effective components for the treatment of liver fibrosis (LF).

Materials and Methods

We collected the active ingredients in SGJPF through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform and screened the effective components by absorption, distribution, metabolism, and excretion. Herb-associated target proteins were predicted and screened based on the Bioinformatics Analysis Tool for Molecular Mechanism of Traditional Chinese Medicine and Search Tool for Interactions of Chemicals databases. LF-associated target proteins were predicted and screened based on the Online Mendelian Inheritance in Man® Database and Comparative Toxicogenomics Database. Common genes with LF and herbs were selected, and Cytoscape 3.5.1 software was used to construct an herb pathway and component-LF common target network. The Search Tool for the Retrieval of Interacting Genes/Proteins was used to build a protein-protein interaction, and quantitative PCR was used to verify the related target genes. Finally, clusterProfiler was applied for the analysis of Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways.

Results

The pharmacological network contained 252 active compounds (e.g., Astragaloside A, saikosaponin, linoleic acid, and Poria acid A), 84 common target genes, and 94 significant signaling pathways. Among them, interleukin 6 (IL-6), tumor protein 53 p53 (TP53), prostaglandin-endoperoxide synthase 2 (PTGS2), AKT1, IL-1β, and the nucleotide-binding and oligomerization domain-like receptor and Janus kinase-signal transducer and activator of transcription signaling pathways were selected as the critical target gene and critical signal pathway, respectively.

Conclusion

The mechanisms of SGJPF in protecting against LF include the regulation of multiple targets such as IL-6, TP53, PTGS2, and AKT1. These target proteins affect LF through various signal transduction pathways.

Therapeutic targeting of JAKs: from hematology to rheumatology and from the first to the second generation of JAK inhibitors

Several cytokines and growth factors, as well as their downstream signalling pathways, are implicated in the pathogenesis of haematological and immune-mediated diseases. These mediators act through binding to their cognate receptor and activation of one or more of the four Janus family tyrosine kinases (JAKs). Gene knock-out studies together with evidence from patients carrying activating mutant forms of JAKs (eg, JAK2 V617F in myeloproliferative disorders) provided strong rationale for the development of JAK inhibitors. Based on encouraging preclinical data showing the capacity of JAK inhibitors to suppress the signalling from multiple cytokines, an extensive drug development program was set out, with the initial successful introduction of tofacitinib, baricitinib and ruxolitinib in various chronic rheumatic and myeloproliferative diseases, respectively. Importantly, advancements with the design of next-generation, hyper-selective JAK inhibitors hold promise for the better control of inflammation, while reducing the risk for harms, in an expanding spectrum of medical disorders.

Unleashing Natural Killer Cells in the Tumor Microenvironment-The Next Generation of Immunotherapy?

The emergence of immunotherapy for cancer treatment bears considerable clinical promise. Nevertheless, many patients remain unresponsive, acquire resistance, or suffer dose-limiting toxicities. Immune-editing of tumors assists their escape from the immune system, and the tumor microenvironment (TME) induces immune suppression through multiple mechanisms. Immunotherapy aims to bolster the activity of immune cells against cancer by targeting these suppressive immunomodulatory processes. Natural Killer (NK) cells are a heterogeneous subset of immune cells, which express a diverse array of activating and inhibitory germline-encoded receptors, and are thus capable of directly targeting and killing cancer cells without the need for MHC specificity. Furthermore, they play a critical role in triggering the adaptive immune response. Enhancing the function of NK cells in the context of cancer is therefore a promising avenue for immunotherapy. Different NK-based therapies have been evaluated in clinical trials, and some have demonstrated clinical benefits, especially in the context of hematological malignancies. Solid tumors remain much more difficult to treat, and the time point and means of intervention of current NK-based treatments still require optimization to achieve long term effects. Here, we review recently described mechanisms of cancer evasion from NK cell immune surveillance, and the therapeutic approaches that aim to potentiate NK function. Specific focus is placed on the use of specialized monoclonal antibodies against moieties on the cancer cell, or on both the tumor and the NK cell. In addition, we highlight newly identified mechanisms that inhibit NK cell activity in the TME, and describe how biochemical modifications of the TME can synergize with current treatments and increase susceptibility to NK cell activity.