Progress in the development of small molecular inhibitors of the Bruton's tyrosine kinase (BTK) as a promising cancer therapy

Therapeutic Potential of Propolis Extract in Managing Hyperinflammation and Long COVID-19: A Bioinformatics Study

Hyperinflammation is a significant factor in long COVID, impacting over 65 million post-COVID-19 individuals globally. Herbal remedies, including propolis, show promise in reducing severity and pro-inflammatory cytokines. However, the natural pharmacological role of propolis in COVID-19 management remains underexplored. Employing network pharmacology and in silico techniques, we assessed propolis extract's potential in countering SARS-CoV-2-induced inflammation. We identified 80 flavonoids via LC-MS/MS QTOF and employed 11 anti-inflammatory drugs as references for inflammation target fishing. Utilizing in silico techniques encompassing target fishing, molecular docking, and dynamics, we examined propolis' effects. We identified 1105 gene targets connected to inflammation through multiple validated target predictors. By integrating SARS-CoV-2 DEGs from GSE147507 with these targets, we identify 25 inflammation-COVID-19-associated propolis targets, including STAT1, NOS2, CFB, EIF2K2, NPY5R, and BTK. Enrichment analyses highlighted primary pharmacological pathways related to Epstein-Barr virus infection and COVID-19. Molecular docking validated isokaempferide, iristectorigenin B, 3'-methoxypuerarin, cosmosiin, and baicalein-7-O-β-d-glucopyranoside, which exhibited strong binding affinity and stability with relevant genes. Moreover, our findings indicate that propolis ligands could potentially suppress reactivation of Epstein-Barr Virus infections in post-COVID-19 cases. However, this study has a limitation in that the concentration of each propolis compound has not been quantified. Therefore, further exploration of propolis compounds quantification and experimental validation are needed to support these findings.

Disease-modifying strategies: Targeting protein kinases in multiple sclerosis and other autoimmune disorders

A wide variety of immunomodulatory therapies are already available for the treatment of multiple sclerosis (MS). Through fundamental insights from basic research with a gain of knowledge in the pathological processes underlying MS, the exploration of additional medical compounds within clinical trials has been ignited. Emerging novel medications with innovative mechanisms of action are being introduced. Those mechanisms of action include a broad therapeutic spectrum of substances targeting various protein kinases, some of which could also be used for the treatment of other autoimmune-mediated diseases. The advancement of new compounds could therefore enable a more personalized approach in treating MS, taking into consideration patients' co-existing autoimmune-mediated diseases. In this review, we discuss potential compounds targeting protein kinases, currently under investigation in clinical trials for various autoimmune diseases that could become viable treatment options for MS and comorbid autoimmune conditions in the future.

Advancements in B-Cell Non-Hodgkin's Lymphoma: From Signaling Pathways to Targeted Therapies

Lymphoma is the sixth most prevalent cancer globally. Non-Hodgkin's lymphomas are the majority group of lymphomas, with B cells accounting for approximately 95% of these lymphomas. A key feature of B-cell lymphoma is the functional perturbations of essential biological pathways caused by genetic aberrations. These lead to atypical gene expression, providing cells with a selective growth advantage. Molecular analysis reveals that each lymphoma subtype has unique molecular mutations, which pose challenges in disease management and treatment. Substantial efforts over the last decade have led to the integration of this information into clinical applications, resulting in crucial insights into clinical diagnosis and targeted therapies. However, with the growing need for more effective medication development, we anticipate a deeper understanding of signaling pathways and their interactions to emerge. This review aims to demonstrate how the BCR, specific signaling pathways like PI3K/AKT/mTOR, NF-kB, and JAK/STAT are diverse in common types of B-cell lymphoma. Furthermore, it offers a detailed examination of each pathway and a synopsis of the approved or in-development targeted therapies. In conclusion, finding the activated signaling pathways is crucial for developing effective treatment plans to improve the prognosis of patients with relapsed or refractory lymphoma. Trial Registration: ClinicalTrials.gov identifier: NCT02180724, NCT02029443, NCT02477696, NCT03836261, NCT02343120, NCT04440059, NCT01882803, NCT01258998, NCT01742988, NCT02055820, NCT02285062, NCT01855750, NCT03422679, NCT01897571.

Discovery of a novel BTK inhibitor S-016 and identification of a new strategy for the treatment of lymphomas including BTK inhibitor-resistant lymphomas

Bruton's tyrosine kinase (BTK) has emerged as a therapeutic target for B-cell malignancies, which is substantiated by the efficacy of various irreversible or reversible BTK inhibitors. However, on-target BTK mutations facilitating evasion from BTK inhibition lead to resistance that limits the therapeutic efficacy of BTK inhibitors. In this study we employed structure-based drug design strategies based on established BTK inhibitors and yielded a series of BTK targeting compounds. Among them, compound S-016 bearing a unique tricyclic structure exhibited potent BTK kinase inhibitory activity with an IC50 value of 0.5 nM, comparable to a commercially available BTK inhibitor ibrutinib (IC50 = 0.4 nM). S-016, as a novel irreversible BTK inhibitor, displayed superior kinase selectivity compared to ibrutinib and significant therapeutic effects against B-cell lymphoma both in vitro and in vivo. Furthermore, we generated BTK inhibitor-resistant lymphoma cells harboring BTK C481F or A428D to explore strategies for overcoming resistance. Co-culture of these DLBCL cells with M0 macrophages led to the polarization of M0 macrophages toward the M2 phenotype, a process known to support tumor progression. Intriguingly, we demonstrated that SYHA1813, a compound targeting both VEGFR and CSF1R, effectively reshaped the tumor microenvironment (TME) and significantly overcame the acquired resistance to BTK inhibitors in both BTK-mutated and wild-type BTK DLBCL models by inhibiting angiogenesis and modulating macrophage polarization. Overall, this study not only promotes the development of new BTK inhibitors but also offers innovative treatment strategies for B-cell lymphomas, including those with BTK mutations.

Evaluation of infectious morbidity due to BTK inhibitors in indolent B-cell lymphomas: latest research findings and systematic analysis

INTRODUCTION

Randomized clinical trials (RCTs) have suggested that BTK inhibitors (BTKis) might increase infectious disease (ID) risk. Systematic analysis of this topic as derived from RCTs and clinical practice is needed.

AREAS COVERED

An extensive Medline, Embase, and Cochrane search of peer-reviewed sources reporting on ID morbidity in patients on BTKis was performed (1 January 2014 - 31 December 2023). Contribution of intrinsic immune defects in indolent B-cell lymphomas to this morbidity was carefully considered.

EXPERT OPINION

Patients with indolent B-cell lymphomas display a wide range of innate and adaptive immune defects. In addition, BTKi use is linked with an increased signal of upper respiratory tract infections (URTIs) and pneumonias, mainly grade 1-2. These agents also increase the risk of rare invasive fungal infections (IFIs), mainly due to Cryptococcus and Aspergillus spp. with a peak within several months after the start of therapy. More than half of these IFIs are fatal. Research suggests a similar ID risk across 1st, 2nd and 3rd generations of BTKis, all causing B-cell dysfunction due to BTK inhibition, along with off-target functional neutrophil/macrophage alterations. Expanding the knowledge base on ID morbidity in patients on BTKis would facilitate timely diagnosis and treatment, and improve clinical outcomes.

Targeted small molecule therapy and inhibitors for lymphoma

Lymphoma, a blood tumor, has become the ninth most common cancer in the world in 2020. Targeted inhibition is one of the important treatments for lymphoma. At present, there are many kinds of targeted drugs for the treatment of lymphoma. Studies have shown that Histone deacetylase, Bruton's tyrosine kinase and phosphoinositide 3-kinase all play an important role in the occurrence and development of tumors and become important and promising inhibitory targets. This article mainly expounds the important role of these target protein in tumors, and introduces the mechanism of action, structure-activity relationship and clinical research of listed small molecule inhibitors of these targets, hoping to provide new ideas for the treatment of lymphoma.

Annual review of PROTAC degraders as anticancer agents in 2022

Following nearly two decades of development, significant advancements have been achieved in PROTAC technology. As of the end of 2022, more than 20 drugs have entered clinical trials, with ARV-471 targeting estrogen receptor (ER) showing remarkable progress by entering phase III clinical studies. In 2022, significant progress has been made on multiple targets. The first reversible covalent degrader designed to target the KRASG12C mutant protein, based on cyclopropionamide, has been reported. Additionally, the activity HDCA1 degrader surpassed submicromolar levels during the same year. A novel FEM1B covalent ligand called EN106 was also discovered, expanding the range of available ligands. Furthermore, the first PROTAC drug targeting SOS1 was reported. Additionally, the first-in-class degraders that specifically target BRD4 isoforms (BRD4 L and BRD4 S) have recently been reported, providing a valuable tool for further investigating the biological functions of these isoforms. Lastly, a breakthrough was also achieved with the first degrader targeting both CDK9 and Cyclin T1. In this review, we aimed to update the PROTAC degraders as potential anticancer agents covering articles published in 2022. The design strategies, degradation effects, and anticancer activities were highlighted, which might provide an updated sight to develop novel PROTAC degraders with great potential as anticancer agents as well as favorable drug-like properties.

Review and prospects of targeted therapies for Spleen tyrosine kinase (SYK)

Spleen tyrosine kinase (SYK) is a non-receptor tyrosine kinase. The dysregulation of SYK is closely related to the occurrence and development of allergic diseases, autoimmune diseases and cancer. SYK has become an attractive target for drug discovery due to its important biological functions. This article reviews the biological function of SYK, the relationship between SYK and disease, and therapies targeting SYK. In addition, inspired by new technologies such as proteolysis targeting chimeras (PROTACs) and phosphatase recruiting chimeras (PHORCs), we propose the development of new therapeutic approaches for targeting SYK, such as SYK PROTACs and SYK PHORCs, which may overcome deficiencies of existing methods.

Molecular associations of response to the new-generation BTK inhibitor zanubrutinib in marginal zone lymphoma

Using tissue whole exome sequencing (WES) and circulating tumor cell-free DNA (ctDNA), this Australasian Leukaemia & Lymphoma Group translational study sought to characterize primary and acquired molecular determinants of response and resistance of marginal zone lymphoma (MZL) to zanubrutinib for patients treated in the MAGNOLIA clinical trial. WES was performed on baseline tumor samples obtained from 18 patients. For 7 patients, ctDNA sequence was interrogated using a bespoke hybrid-capture next-generation sequencing assay for 48 targeted genes. Somatic mutations were correlated with objective response data and survival analysis using Fisher exact test and Kaplan-Meier (log-rank) method, respectively. Baseline WES identified mutations in 33 of 48 (69%) prioritized genes. NF-κB, NOTCH, or B-cell receptor (BCR) pathway genes were implicated in samples from 16 of 18 patients (89%). KMT2D mutations (n = 11) were most common, followed by FAT1 (n = 9), NOTCH1, NOTCH2, TNFAIP3 (n = 5), and MYD88 (n = 4) mutations. MYD88 or TNFAIP3 mutations correlated with improved progression-free survival (PFS). KMT2D mutations trended to worse PFS. Acquired resistance mutations PLCG2 (R665W/R742P) and BTK (C481Y/C481F) were detected in 2 patients whose disease progressed. A BTK E41K noncatalytic activating mutation was identified before treatment in 1 patient who was zanubrutinib-refractory. MYD88, TNFAIP3, and KMT2D mutations correlate with PFS in patients with relapsed/refractory MZL treated with zanubrutinib. Detection of acquired BTK and PLCG2 mutations in ctDNA while on therapy is feasible and may herald clinical disease progression. This trial was registered at https://anzctr.org.au/ as #ACTRN12619000024145.

The preclinical discovery and development of orelabrutinib as a novel treatment option for B-cell lymphoid malignancies

INTRODUCTION

Bruton's tyrosine kinase (BTK) inhibitors have recently been approved for clinical use against several B-cell indolent lymphoid malignancies, both as single agents or in combination. One second-generation BTK inhibitor that is being developed for the treatment of B-cell hematological malignancies, as well as for autoimmune disorders, is orelabrutinib.

AREAS COVERED

This paper reviews recent developments in the use of orelabrutinib against B-cell indolent lymphoid malignancies such as chronic lymphocytic leukemia, mantle cell lymphoma, diffuse large B-cell lymphoma, Waldenstrom macroglobulinemia and central nervous system lymphoma. Google Scholar and PubMed were initially searched for articles, and the corpus of articles was broadened by reviewing the references of the identified papers. All were in English. The corpus comprised papers from 2016 to April 2023. In addition, a manual search was performed of conference proceedings from the last five years of The American Society of Hematology, American Society of Clinical Oncology and the European Hematology Association.

EXPERT OPINION

Orelabrutinib is an active drug in indolent and aggressive B-cell lymphoid malignancies. It demonstrates high selectivity, good efficacy and an excellent safety profile. Nevertheless, further clinical trials are required to optimize its use. In addition, several other highly selective BTK inhibitors are being examined in early-phase studies.

PROTACs in the Management of Prostate Cancer

Cancer treatments with targeted therapy have gained immense interest due to their low levels of toxicity and high selectivity. Proteolysis-Targeting Chimeras (PROTACs) have drawn special attention in the development of cancer therapeutics owing to their unique mechanism of action, their ability to target undruggable proteins, and their focused target engagement. PROTACs selectively degrade the target protein through the ubiquitin-proteasome system, which describes a different mode of action compared to conventional small-molecule inhibitors or even antibodies. Among different cancer types, prostate cancer (PC) is the most prevalent non-cutaneous cancer in men. Genetic alterations and the overexpression of several genes, such as FOXA1, AR, PTEN, RB1, TP53, etc., suppress the immune response, resulting in drug resistance to conventional drugs in prostate cancer. Since the progression of ARV-110 (PROTAC for PC) into clinical phases, the focus of research has quickly shifted to protein degraders targeting prostate cancer. The present review highlights an overview of PROTACs in prostate cancer and their superiority over conventional inhibitors. We also delve into the underlying pathophysiology of the disease and explain the structural design and linkerology strategies for PROTAC molecules. Additionally, we touch on the various targets for PROTAC in prostate cancer, including the androgen receptor (AR) and other critical oncoproteins, and discuss the future prospects and challenges in this field.

Recent development of multi-target VEGFR-2 inhibitors for the cancer therapy

Vascular epidermal growth factor receptor-2 (VEGFR-2), as an important tyrosine transmembrane protein, plays an important role in regulating endothelial cell proliferation and migration, regulating angiogenesis and other biological functions. VEGFR-2 is aberrantly expressed in many malignant tumors, and it is also related to the occurrence, development, and growth of tumors and drug resistance. Currently, there are nine VEGFR-2 targeted inhibitors approved by US.FDA for clinical use as anticancer drugs. Due to the limited clinical efficacy and potential toxicity of VEGFR inhibitors, it is necessary to develop new strategies to improve the clinical efficacy of VEGFR inhibitors. The development of multitarget therapy, especially dual-target therapy, has become a hot research field of cancer therapy, which may provide an effective strategy with higher therapeutic efficacy, pharmacokinetic advantages and low toxicity. Many groups have reported that the therapeutic effects could be improved by simultaneously inhibiting VEGFR-2 and other targets, such as EGFR, c-Met, BRAF, HDAC, etc. Therefore, VEGFR-2 inhibitors with multi-targeting capabilities have been considered to be promising and effective anticancer agents for cancer therapy. In this work, we reviewed the structure and biological functions of VEGFR-2, and summarized the drug discovery strategies, and inhibitory activities of VEGFR-2 inhibitors with multi-targeting capabilities reported in recent years. This work might provide the reference for the development of VEGFR-2 inhibitors with multi-targeting capabilities as novel anticancer agents.

Bruton's Tyrosine Kinase Inhibitors (BTKIs): Review of Preclinical Studies and Evaluation of Clinical Trials

In the last few decades, there has been a growing interest in Bruton's tyrosine kinase (BTK) and the compounds that target it. BTK is a downstream mediator of the B-cell receptor (BCR) signaling pathway and affects B-cell proliferation and differentiation. Evidence demonstrating the expression of BTK on the majority of hematological cells has led to the hypothesis that BTK inhibitors (BTKIs) such as ibrutinib can be an effective treatment for leukemias and lymphomas. However, a growing body of experimental and clinical data has demonstrated the significance of BTK, not just in B-cell malignancies, but also in solid tumors, such as breast, ovarian, colorectal, and prostate cancers. In addition, enhanced BTK activity is correlated with autoimmune disease. This gave rise to the hypothesis that BTK inhibitors can be beneficial in the therapy of rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), multiple sclerosis (MS), Sjögren's syndrome (SS), allergies, and asthma. In this review article, we summarize the most recent findings regarding this kinase as well as the most advanced BTK inhibitors that have been developed to date and their clinical applications mainly in cancer and chronic inflammatory disease patients.

Quantification of orelabrutinib in human plasma and cerebrospinal fluid by liquid chromatography tandem mass spectrometry

A sensitive and simple method was developed to determine orelabrutinib in human plasma and cerebrospinal fluid by liquid chromatography tandem mass spectrometry (LC-MS/MS). The samples were prepared by simple protein precipitation with by 0.1% formic acid acetonitrile solution and efficient separations were performed on the Thermo Hypersll GOLD C18 column (2.1 mm × 150 mm, 5 μm) under a gradient program in a total run time of 9 min. The orelabrutinib was detected by electrospray ionization in positive ion mode with selective reaction monitoring (SRM) and mass spectrometric conditions were optimized in order to increase selectivity and sensitivity. The developed method was validated in terms of its accuracy, precision, selectivity, linearity, recovery, matrix effect, stability, and limits of quantification (LOQ). The lower limit of quantification is 0.50 ng/mL, the intraday and interday precision RSD are both less than 15%, and the recovery rate is 85.7%-92.9%. Finally, the method was successfully applied for the quantitation of orelabrutinib in human plasma and cerebrospinal fluid of clinical patients treated with orelabrutinib.

Design, synthesis and pharmacological characterization of aminopyrimidine derivatives as BTK/FLT3 dual-target inhibitors against acute myeloid leukemia

A novel class of aminopyrimidine-based Bruton's tyrosine kinase (BTK) and FMS-like tyrosine kinase 3 (FLT3) dual-target inhibitors based on the BTK inhibitor spebrutinib was designed for the treatment of acute myeloid leukemia. Representative compounds 14d, 14g, 14j and 14m effectively inhibited BTK, FLT3, and FLT3(D835Y) mutant activities with low nanomolar IC₅₀'s. These compounds displayed potent antiproliferative activities against leukemia cells with IC₅₀'s of 0.29-950 nM. In particular, 14m had IC₅₀ values 101-1045 times lower than those of spebrutinib against all cancer cell lines tested. Compound 14m effectively induced autophagy and apoptosis in MV-4-11 cells through regulating related proteins in a dose-dependent manner. Finally, intraperitoneal administration of 14m at 20 mg/kg significantly repressed the growth of MV-4-11 cells with a TGI value of 95.68% with no apparent toxicity. These BTK/FLT3 dual-target inhibitors represent promising leads for further structural optimization and antitumor mechanism studies.

Small molecule inhibitors targeting the cancers

Compared with traditional therapies, targeted therapy has merits in selectivity, efficacy, and tolerability. Small molecule inhibitors are one of the primary targeted therapies for cancer. Due to their advantages in a wide range of targets, convenient medication, and the ability to penetrate into the central nervous system, many efforts have been devoted to developing more small molecule inhibitors. To date, 88 small molecule inhibitors have been approved by the United States Food and Drug Administration to treat cancers. Despite remarkable progress, small molecule inhibitors in cancer treatment still face many obstacles, such as low response rate, short duration of response, toxicity, biomarkers, and resistance. To better promote the development of small molecule inhibitors targeting cancers, we comprehensively reviewed small molecule inhibitors involved in all the approved agents and pivotal drug candidates in clinical trials arranged by the signaling pathways and the classification of small molecule inhibitors. We discussed lessons learned from the development of these agents, the proper strategies to overcome resistance arising from different mechanisms, and combination therapies concerned with small molecule inhibitors. Through our review, we hoped to provide insights and perspectives for the research and development of small molecule inhibitors in cancer treatment.

Comparison of Intermolecular Interactions of Irreversible and Reversible Inhibitors with Bruton’s Tyrosine Kinase via Molecular Dynamics Simulations

Bruton’s tyrosine kinase (BTK) is a key protein from the TEC family and is involved in B-cell lymphoma occurrence and development. Targeting BTK is therefore an effective strategy for B-cell lymphoma treatment. Since previous studies on BTK have been limited to structure-function analyses of static protein structures, the dynamics of conformational change of BTK upon inhibitor binding remain unclear. Here, molecular dynamics simulations were conducted to investigate the molecular mechanisms of association and dissociation of a reversible (ARQ531) and irreversible (ibrutinib) small-molecule inhibitor to/from BTK. The results indicated that the BTK kinase domain was found to be locked in an inactive state through local conformational changes in the DFG motif, and P-, A-, and gatekeeper loops. The binding of the inhibitors drove the outward rotation of the C-helix, resulting in the upfolded state of Trp395 and the formation of the salt bridge of Glu445-Arg544, which maintained the inactive conformation state. Met477 and Glu475 in the hinge region were found to be the key residues for inhibitor binding. These findings can be used to evaluate the inhibitory activity of the pharmacophore and applied to the design of effective BTK inhibitors. In addition, the drug resistance to the irreversible inhibitor Ibrutinib was mainly from the strong interaction of Cys481, which was evidenced by the mutational experiment, and further confirmed by the measurement of rupture force and rupture times from steered molecular dynamics simulation. Our results provide mechanistic insights into resistance against BTK-targeting drugs and the key interaction sites for the development of high-quality BTK inhibitors. The steered dynamics simulation also offers a means to rapidly assess the binding capacity of newly designed inhibitors.

Recent development of BTK-based dual inhibitors in the treatment of cancers

Bruton's tyrosine kinase (BTK) is a promising target in the treatment of various cancers. Despite the early success of BTK inhibitors in the clinic, these single-target drug therapies have limitations in their clinical applications, such as drug resistance. Several alternative strategies have been developed, including the use of dual inhibitors, to maximize the therapeutic potential of anticancer drugs. In this review, we highlight the scientific background and theoretical basis for developing BTK-based dual inhibitors, as well as the status of these agents in preclinical and clinical studies, and discuss further options in this field. We posit that these advances in BTK-based dual inhibitors confirm their feasibility for the treatment of refractory tumors, including those with drug resistance, and provide a framework for future drug design in this field. Accordingly, we anticipate increasingly rapid progress in the development of novel potent dual inhibitors and advanced clinical research on BTK-based dual inhibitors.

Intracellular Reduction-Responsive Molecular Targeted Nanomedicine for Hepatocellular Carcinoma Therapy

The stimuli-responsive polymer-based platform for controlled drug delivery has gained increasing attention in treating hepatocellular carcinoma (HCC) owing to the fascinating biocompatibility and biodegradability, improved antitumor efficacy, and negligible side effects recently. Herein, a disulfide bond-contained polypeptide nanogel, methoxy poly(ethylene glycol)-poly(l-phenylalanine-co-l-cystine) [mPEG-P(LP-co-LC)] nanogel, which could be responsive to the intracellular reduction microenvironments, was developed to deliver lenvatinib (LEN), an inhibitor of multiple receptor tyrosine kinases, for HCC therapy. The lenvatinib-loaded nanogel (NG/LEN) displayed concise drug delivery under the stimulus of glutathione in the cancer cells. Furthermore, the intracellular reduction-responsive nanomedicine NG/LEN showed excellent antitumor effect and almost no side effects toward both subcutaneous and orthotopic HCC tumor-allografted mice in comparison to free drug. The excellent tumor-inhibition efficacy with negligible side effects demonstrated the potential of NG/LEN for clinical molecular targeted therapy of gastrointestinal carcinoma in the future.