A preclinical evaluation of Minnelide as a therapeutic agent against pancreatic cancer

Co‑treatment with triptolide and RSL3 induces hepatocellular carcinoma cell apoptosis and ferroptosis

Glutathione peroxidase 4 (GPx4; also known as phospholipid hydroperoxide glutathione peroxidase) inhibits cell death, including apoptosis and ferroptosis, by reducing lipid peroxidation. In addition, western blot assays showed that GPx4 protein levels were elevated in hepatocellular carcinoma (HCC) cells following triptolide (TPL) treatment. Therefore, it was hypothesized that HCC cells might develop partial resistance to TPL‑induced cytotoxicity through upregulation of the GPx4 protein. To enhance anti‑proliferative efficacy, the present study co‑treated HCC cells with a combination of TPL and RAS‑selective lethal 3 (RSL3), a well‑characterized GPx4 activity inhibitor. Subsequent experimental data produced from Cell Counting Kit‑8 and flow cytometric analyses demonstrated that co‑administration of TPL and RSL3 promoted HCC cell apoptosis, elevated intracellular reactive oxygen species levels and induced ferroptosis. These collective findings suggested that co‑treatment with TPL and RSL3 may induce both apoptotic and ferroptotic pathways in HCC cells.

Pharmacological, computational, and mechanistic insights into triptolide's role in targeting drug-resistant cancers

As a promising candidate for tackling drug-resistant cancers, triptolide, a diterpenoid derived from the Chinese medicinal plant Tripterygium wilfordii, has been developed. This review summarizes potential antitumor activities, including the suppression of RNA polymerase II, the suppression of heat shock proteins (HSP70 and HSP90), and the blockade of NF-kB signalling. Triptolide is the first known compound to target cancer cells specifically but spare normal cells, and it has success in treating cancers that are difficult to treat, including pancreatic, breast, and lung cancers. It acts against the tolerance mechanisms, including efflux pump upregulation, epithelial-mesenchymal transition, and cancer stem cells. Triptolide modulates important cascades, including PI3K/AKT/mTOR, enhancing the efficacy of conventional therapies. Nonetheless, its clinical application is constrained by toxicity and bioavailability challenges. Emerging drug delivery systems, such as nanoparticles and micellar formulations, are being developed to address these limitations. It has strong interactions with key anticancer targets, like PARP, as determined in preclinical and computational studies consistent with its mechanism of action. Early-phase clinical trials of Minnelide, a water-soluble derivative of triptolide, are promising, but additional work is necessary to optimize dosing, delivery, and safety. This comprehensive analysis demonstrates that triptolide may constitute a repurposed precision medicine tool to overcome tolerance in cancer therapy.

Anti-SARS-CoV-2 and anticancer properties of triptolide and its derived carbonized nanomaterials

The COVID-19 pandemic remains an ongoing global health threat, yet effective treatments are still lacking. This has led to a high demand for complementary/alternative medicine, such as Chinese herbal medicines for curbing the COVID-19 pandemic. Given the dual anticancer and antiviral activities of many herbal drugs, they may hold a multifaceted potential to tackle both cancer and SARS-CoV-2. Triptolide is the major bioactive compound isolated from Tripterygium wilfordii Hook F (TwHF), a traditional Chinese medicinal herb recognized for its beneficial pharmacological properties in many diseases, including cancer and viral infection. However, its application in the clinic has been greatly limited due to its toxicity and poor water solubility. Here, from a screen of a natural compound library of Chinese Pharmacopoeia, we identified triptolide as a top candidate to inhibit cell entry of SARS-CoV-2. We demonstrated that triptolide robustly blocked viral entry at nanomolar concentrations in cellular models, with broad range activity against emerging Omicron variants of SARS-CoV-2. Mechanistically, triptolide disrupted the interaction of SARS-CoV-2 spike protein with its receptor ACE2. Furthermore, we synthesized water-soluble, triptolide-derived carbon quantum dots. Compared to triptolide, these highly biocompatible nanomaterials exhibited prominent antiviral capabilities against Omicron variants of SARS-CoV-2 with less cytotoxicity. Finally, we showed that triptolide-derived carbonized materials excelled in their anticancer properties compared to triptolide and Minnelide, a water-soluble analog of triptolide. Together, our results provide a rationale for the potential development of triptolide-carbonized derivatives as a promising antiviral candidate for the current pandemic and future outbreaks, as well as anticancer agents.

Therapeutic potential of Triptolide in inhibiting breast cancer-induced bone destruction - PTHrP as a therapeutic target

Introduction

Bone metastases are a common and severe complication in advanced breast cancer, affecting approximately 65% to 70% of patients and significantly reducing survival time. Osteolytic bone metastases, in particular, are challenging to manage due to their association with skeletal-related events (SREs) that accelerate disease progression and diminish the quality of life. These metastases are driven by a complex interaction between breast cancer cells and the bone microenvironment, leading to increased osteoclast activity and bone destruction. Current treatments, such as bisphosphonates, primarily aim to inhibit osteoclast function but are associated with serious side effects, underscoring the need for alternative therapies. Triptolide (TP), a bioactive compound derived from the traditional Chinese medicinal herb Tripterygium wilfordii Hook F. (TwHF), has demonstrated potent anti-tumor and anti-inflammatory properties, especially in abnormal bone remodeling disorders. This study aims to investigate the therapeutic potential of TP in treating breast cancer-induced bone metastases by examining its effects on osteoclastogenesis and tumor-bone microenvironment interactions.

Methods

Mouse bone marrow cells, RAW264.7 pre-osteoclasts and MC3T3-E1 pre-osteoblasts were cultured with MDA-MB-231 breast cancer cells or their conditioned medium to replicate the tumor microenvironment. Osteoclast formation was assessed via TRAP staining. Translational and transcriptional expression of key signaling molecules and related markers were determined using western blot and RT-PCR. Binding interactions between TP and parathyroid hormone-related protein (PTHrP) were analyzed using microscale thermophoresis and molecular docking.

Results

TP treatment significantly reduced osteoclastogenesis in both co-culture and conditioned medium systems. Our findings suggest that TP inhibits NF-κB and ERK signaling pathways, reduces breast cancer-induced osteoclastogenesis, and decreases NFATc1, CTSK, and RANKL expression. Molecular assays revealed a direct binding affinity between TP and PTHrP, suggesting TP interferes with PTHrP-mediated signaling that promotes osteoclast activity.

Discussion

This study demonstrates that Triptolide effectively inhibits breast cancer-induced osteolytic bone metastasis by suppressing key osteoclastogenic signaling pathways and modulating the tumor-bone microenvironment. We provide the first evidence of a direct interaction between TP and PTHrP, suggesting a novel mechanism through which TP may disrupt PTHrP-mediated osteoclast activation. These findings position TP as a promising alternative to current anti-resorptive therapies for managing breast cancer-associated bone metastases.

Therapy resistance: Modulating evolutionarily conserved heat shock protein machinery in cancer

Therapy resistance is a major barrier to achieving a cure in cancer patients, often resulting in relapses and mortality. Heat shock proteins (HSPs) are a group of evolutionarily conserved proteins that play a prominent role in the progression of cancer and drug resistance. HSP synthesis is upregulated in cancer cells, facilitating adaptation to various tumor microenvironment (TME) stressors, including nutrient deprivation, exposure to DNA-damaging agents, hypoxia, and immune responses. In this review, we present background information about HSP-mediated cancer therapy resistance. Within this context, we emphasize recent progress in the understanding of HSP machinery, exploring the therapeutic potential of HSPs in cancer treatment.

Genome-wide characterization and expression analysis of WRKY family genes in the biosynthesis of triptolide in Tripterygium wilfordii

BACKGROUND

WRKY transcription factors play a vital role in regulating plant growth, development, and secondary metabolism. Tripterygium wilfordii is a medicinal plant that has been widely utilized in rheumatoid arthritis therapy; it contains triptolide, a prominent bioactive constituent exhibiting potent anti-inflammatory and anti-tumor properties. However, the mechanism underlying the regulatory effects of WRKY on triptolide biosynthesis is poorly understood.

RESULTS

In this study, 95 TwWRKY genes were identified in the T. wilfordii genome, which were divided into three groups. Phylogenetic analysis indicated that the TwWRKY were conservative relative to other plants. Collinearity analysis revealed that gene duplications played a crucial role in the evolution of this gene family. Transcriptome data from various plant tissues were integrated by correlation analysis, and a gene-to-metabolite network was successfully mapped; consequently, 32 TwWRKY genes were selected as potential regulators of triptolide biosynthesis. Furthermore, the expression changes in the 32 TwWRKY genes were analyzed following methyl jasmonate (MeJA) induction, and the key candidates likely to regulate the biosynthesis of triptolide were screened. Finally, we performed subcellular localization on the key candidate gene TW23G00056.1 and found that it plays its biological role in the nucleus.

CONCLUSION

Our study provides a valuable resource for further research on TwWRKY in T. wilfordii. The candidate genes reported here lay the foundation for elucidating the regulatory mechanism of triptolide.

Recent Advances and Challenges in the Treatment of Advanced Pancreatic Cancer: An Update on Completed and Ongoing Clinical Trials

Pancreatic cancer is a deadly disease with a low survival rate, particularly in its advanced stages. Advanced pancreatic cancer remains a major clinical challenge due to limited treatment options. Surgical resection may not always be feasible, and traditional chemotherapy often shows restricted effectiveness. As a result, researchers are exploring a multifaceted therapeutic approach targeting the genetic and molecular drivers of the disease. A combination of molecular profiling and targeted therapies are being investigated to improve outcomes and address the shortcomings of traditional treatments. The focus of this review is to provide a summary of current and completed clinical trials for the treatment of advanced pancreatic cancer. This includes adagrasib (a KRAS inhibitor), olaparib (a PARP inhibitor for BRCA mutations), APG-1387 (an IAP antagonist), minnelide (an anti-stromal agent), arimastat (an MMP inhibitor), MK-0646 (an IGF1R inhibitor), sirolimus (an mTOR inhibitor), and metabolic inhibitors. These agents are being evaluated both as standalone treatments and in combination with standard therapy. Furthermore, we have summarized novel approaches such as cancer vaccines and ablation techniques as emerging strategies in the treatment of advanced pancreatic cancer. We have also examined the challenges in treating advanced pancreatic cancer and the factors contributing to therapeutic failure, which may offer valuable insights for developing more effective treatment strategies and innovative drug designs.

The dual-function of HSP70 in immune response and tumor immunity: from molecular regulation to therapeutic innovations

Heat shock protein 70 (HSP70) is a highly conserved molecular chaperone that plays a core role in assisting protein folding and maintaining cellular homeostasis. In recent years, studies have revealed that HSP70 has dual functions in immune regulation: on the one hand, it enhances immune responses by activating non-specific immunity (such as Toll-like receptor 2/4 (TLR2/4) signaling pathways) and specific immunity (such as cross-presentation of antigens, T helper 1 (Th1)/T helper 17 (Th17) differentiation); on the other hand, it inhibits excessive immune reactions by inducing the differentiation of regulatory T cells (Treg) and promoting the secretion of anti-inflammatory factors [such as interleukin-10 (IL-10)]. In cancer, the duality of HSP70 is also very prominent: it can drive tumor progression through pathways such as inhibiting apoptosis, promoting angiogenesis, and tumor metastasis, and it can also inhibit tumor growth by activating immunogenic cell death (ICD), enhancing antigen presentation, and natural killer (NK) cell activity. This review aims to systematically analyze the immune regulatory functions of HSP70, focusing on its dual regulatory mechanisms and the "double-edged sword" nature of HSP70 in tumor immunotherapy and the innovative nature of targeted strategies, as well as providing a theoretical basis and research directions for precision medicine in the treatment strategies of related diseases.

Potential antitumor activity of triptolide and its derivatives: Focused on gynecological and breast cancers

Cancer remains one of the greatest global health concerns. This is especially true for gynecological cancers, which include cervical, ovarian, and endometrial cancers, and breast cancer. Natural products used for cancer treatment offer some unique advantages. Triptolide (TPL) is a biologically active terpenoid extracted from Tripterygium wilfordii, which exhibits anti-inflammatory, immunosuppressive, antitumor, and other pharmacological activities. However, clinical applications of TPL are restricted because of poor water solubility and severe cytotoxicity; to overcome these limitations, various TPL derivatives and drug delivery systems, especially nanocarriers, have been used. Furthermore, various preclinical and clinical studies have demonstrated that TPL and its derivatives exhibit excellent antitumor effects by targeting proteins involved in multiple signaling pathways. Here, we review the progress regarding novel drug delivery systems, antitumor activities, and molecular mechanisms of action of TPL and its derivatives against gynecological and breast cancers. TPL and its derivatives inhibit tumor growth, suppress tumor metastasis, and enhance the drug sensitization of resistant cancers. In addition, TPL and its derivatives exert synergistic antitumor effects against gynecological and breast cancers when combined with existing antitumor drugs, such as carboplatin, cisplatin, and PI3K inhibitors. Moreover, we highlight the clinical potential of TPL analogs against cancer from bench to bedside and their prospects for future applications in gynecologic and breast cancers.

Dual activity of Minnelide chemosensitize basal/triple negative breast cancer stem cells and reprograms immunosuppressive tumor microenvironment

Triple negative breast cancer (TNBC) subtype is characterized with higher EMT/stemness properties and immune suppressive tumor microenvironment (TME). Women with advanced TNBC exhibit aggressive disease and have limited treatment options. Although immune suppressive TME is implicated in driving aggressive properties of basal/TNBC subtype and therapy resistance, effectively targeting it remains a challenge. Minnelide, a prodrug of triptolide currently being tested in clinical trials, has shown anti-tumorigenic activity in multiple malignancies via targeting super enhancers, Myc and anti-apoptotic pathways such as HSP70. Distinct super-enhancer landscape drives cancer stem cells (CSC) in TNBC subtype while inducing immune suppressive TME. We show that Minnelide selectively targets CSCs in human and murine TNBC cell lines compared to cell lines of luminal subtype by targeting Myc and HSP70. Minnelide in combination with cyclophosphamide significantly reduces the tumor growth and eliminates metastasis by reprogramming the tumor microenvironment and enhancing cytotoxic T cell infiltration in 4T1 tumor-bearing mice. Resection of residual tumors following the combination treatment leads to complete eradication of disseminated tumor cells as all mice are free of local and distant recurrences. All control mice showed recurrences within 3 weeks of post-resection while single Minnelide treatment delayed recurrence and one mouse was free of tumor. We provide evidence that Minnelide targets tumor intrinsic pathways and reprograms the immune suppressive microenvironment. Our studies also suggest that Minnelide in combination with cyclophosphamide may lead to durable responses in patients with basal/TNBC subtype warranting its clinical investigation.

Reversible chemoresistance of pancreatic cancer grown as spheroids

Better in vitro models are needed to identify active drugs to treat pancreatic adenocarcinoma (PAC) patients. We used 3D hanging drop cultures to produce spheroids from five PAC cell lines and tested nine FDA-approved drugs in clinical use. All PAC cell lines in 2D culture were sensitive to three drugs (gemcitabine, docetaxel and nab-paclitaxel), however most PAC (4/5) 3D spheroids acquired profound chemoresistance even at 10 µM. In contrast, spheroids retained sensitivity to the investigational drug triptolide, which induced apoptosis. The acquired chemoresistance was also transiently retained when cells were placed back into 2D culture and six genes potentially associated with chemoresistance were identified by microarray and confirmed using quantitative RT-PCR. We demonstrate the additive effect of gemcitabine and erlotinib, from the 12 different combinations of nine drugs tested. This comprehensive study shows spheroids as a useful multicellular model of PAC for drug screening and elucidating the mechanism of chemoresistance.

Discovery of natural product derivative triptolidiol as a direct NLRP3 inhibitor by reducing K63-specific ubiquitination

BACKGROUND AND PURPOSE

NLRP3 is up-regulated in inflammatory and autoimmune diseases. The development of NLRP3 inhibitors is challenged by the identification of compounds with distinct mechanisms of action avoiding side effects and toxicity. Triptolide is a natural product with multiple anti-inflammatory activities, but a narrow therapeutic window.

EXPERIMENTAL APPROACH

Natural product triptolide derivatives were screened for NLRP3 inhibitors in human THP-1 and mouse bone marrow-derived macrophages. The efficacy of potent NLRP3 inhibitors was evaluated in LPS-induced acute lung injury and septic shock models.

KEY RESULTS

Triptolidiol was identified as a selective inhibitor of NLRP3 with high potency. Triptolidiol inactivated the NLRP3 inflammasome in human THP-1 and mouse primary macrophages primed with LPS. Triptolidiol specifically inhibited pro-caspase 1 cleavage downstream of NLRP3, but not AIM2 or NLRC4 inflammasomes. Based on the structure-activity relationship study, the C8-β-OH group was critical for its binding to NLRP3. Triptolidiol exhibited a submicromolar KD for NLRP3, binding to residue C280. This binding prevented the interaction of NLRP3 with NEK7, the key regulator of NLRP3 inflammasome oligomerization and assembly, but not with the inflammasome adaptor protein ASC. Triptolidiol decreased the K63-specific ubiquitination of NLRP3, leading NLRP3 to a "closed" inactive conformation. Intraperitoneal administration of triptolidiol significantly attenuated LPS-induced acute lung injury and lethal septic shock.

CONCLUSION AND IMPLICATIONS

Triptolidiol is a novel NLRP3 inhibitor that regulates inflammasome assembly and activation by decreasing K63-linked ubiquitination. Triptolidiol has novel structural features that make it distinct from reported NLRP3 inhibitors and represents a viable therapeutic lead for inflammatory diseases.

The safety and efficacy outcomes of Minnelide given alone or in combination with paclitaxel in advanced gastric cancer: A phase I trial

Minnelide is a water-soluble disodium salt variant of triptolide, an HSP70 inhibitor that can prevent tumor progression and induce apoptosis. Maximum tolerated dose (MTD), safety, and antitumor activity of Minnelide alone and its combination with paclitaxel were evaluated in this open-label, single-center, dose-escalation phase I study (NCT05566834) in patients who were previously treated for advanced gastric cancer (AGC). Minnelide was administered orally using a 3 + 3 dose-escalation design as monotherapy (Regimen A), and in combination with paclitaxel (Regimen B & C). Our results show that no patients experienced dose limiting toxicity (DLT) in the combination group (Regimen B& C) while 2 patients experienced DLT from the Regimen A group (n = 11) (Minnelide 1.5 mg). The MTD was Minnelide 1.25 mg once daily for 21days Q4 weeks as monotherapy. The most common Grade ≥3 AEs were neutropenia (19.4 %) and abdominal pain (11.1 %). In Regimen C, 71.5 % achieved either a partial response or a stable disease with the median PFS of 4.5 months, and the median OS of 10.7 months. The combination of Minnelide plus paclitaxel as salvage treatment in AGC patients showed meaningful clinical activity with a manageable safety profile. Based on these encouraging results, a phase II study is being initiated to test the effectiveness of the combination regimen in patients with advanced gastric cancer.

Minnelide exhibits antileukemic activity by targeting the Ars2/miR-190a-3p axis

BACKGROUND

The identification of a novel and effective strategy for the clinical treatment of acute leukemia (AL) is a long-term goal. Minnelide, a water-soluble prodrug of triptolide, has recently been evaluated in phase I and II clinical trials in patients with multiple cancers and has shown promise as an antileukemic agent. However, the molecular mechanism underlying minnelide's antileukemic activity remains unclear.

PURPOSE

To explore the molecular mechanisms by which minnelide exhibits antileukemic activity.

METHODS

AL cells, primary human leukemia cells, and a xenograft mouse model were treated with triptolide and minnelide. The molecular mechanism was elucidated using western blotting, immunoprecipitation, flow cytometry, GSEA and liquid chromatography-mass spectrometry analysis.

RESULTS

Minnelide was highly effective in inhibiting leukemogenesis and improving survival in two complementary AL mouse models. Triptolide, an active form of minnelide, causes cell cycle arrest in G1 phase and induces apoptosis in both human AL cell lines and primary AL cells. Mechanistically, we identified Ars2 as a new chemotherapeutic target of minnelide for AL treatment. We found that triptolide directly targeted Ars2, resulting in the downregulation of miR-190a-3p, which led to the disturbance of PTEN/Akt signaling and culminated in G1 cell cycle arrest and apoptosis.

CONCLUSIONS

Our findings demonstrate that targeting Ars2/miR-190a-3p signaling using minnelide could represent a novel chemotherapeutic strategy for AL treatment and support the evaluation of minnelide for the treatment of AL in clinical trials.

Triptolide and its prodrug Minnelide target high-risk MYC-amplified medulloblastoma in preclinical models

Most children with medulloblastoma (MB) achieve remission, but some face very aggressive metastatic tumors. Their dismal outcome highlights the critical need to advance therapeutic approaches that benefit such high-risk patients. Minnelide, a clinically relevant analog of the natural product triptolide, has oncostatic activity in both preclinical and early clinical settings. Despite its efficacy and tolerable toxicity, this compound has not been evaluated in MB. Utilizing a bioinformatic data set that integrates cellular drug response data with gene expression, we predicted that Group 3 (G3) MB, which has a poor 5-year survival, would be sensitive to triptolide/Minnelide. We subsequently showed that both triptolide and Minnelide attenuate the viability of G3 MB cells ex vivo. Transcriptomic analyses identified MYC signaling, a pathologically relevant driver of G3 MB, as a downstream target of this class of drugs. We validated this MYC dependency in G3 MB cells and showed that triptolide exerts its efficacy by reducing both MYC transcription and MYC protein stability. Importantly, Minnelide acted on MYC to reduce tumor growth and leptomeningeal spread, which resulted in improved survival of G3 MB animal models. Moreover, Minnelide improved the efficacy of adjuvant chemotherapy, further highlighting its potential for the treatment of MYC-driven G3 MB.

Antitumor mechanisms and future clinical applications of the natural product triptolide

Triptolide (TPL) is a compound sourced from Tripterygium wilfordii Hook. F., a traditional Chinese medicinal herb recognized for its impressive anti-inflammatory, anti-angiogenic, immunosuppressive, and antitumor qualities. Notwithstanding its favorable attributes, the precise mechanism through which TPL influences tumor cells remains enigmatic. Its toxicity and limited water solubility significantly impede the clinical application of TPL. We offer a comprehensive overview of recent research endeavors aimed at unraveling the antitumor mechanism of TPL in this review. Additionally, we briefly discuss current strategies to effectively manage the challenges associated with TPL in future clinical applications. By compiling this information, we aim to enhance the understanding of the underlying mechanisms involved in TPL and identify potential avenues for further advancement in antitumor therapy.

Liposome-Hydrogel Composites for Controlled Drug Delivery Applications

Various controlled delivery systems (CDSs) have been developed to overcome the shortcomings of traditional drug formulations (tablets, capsules, syrups, ointments, etc.). Among innovative CDSs, hydrogels and liposomes have shown great promise for clinical applications thanks to their cost-effectiveness, well-known chemistry and synthetic feasibility, biodegradability, biocompatibility and responsiveness to external stimuli. To date, several liposomal- and hydrogel-based products have been approved to treat cancer, as well as fungal and viral infections, hence the integration of liposomes into hydrogels has attracted increasing attention because of the benefit from both of them into a single platform, resulting in a multifunctional drug formulation, which is essential to develop efficient CDSs. This short review aims to present an updated report on the advancements of liposome-hydrogel systems for drug delivery purposes.

Minnelide suppresses GVHD and enhances survival while maintaining GVT responses

Allogeneic hematopoietic stem cell transplantation (aHSCT) can cure patients with otherwise fatal leukemias and lymphomas. However, the benefits of aHSCT are limited by graft-versus-host disease (GVHD). Minnelide, a water-soluble analog of triptolide, has demonstrated potent antiinflammatory and antitumor activity in several preclinical models and has proven both safe and efficacious in clinical trials for advanced gastrointestinal malignancies. Here, we tested the effectiveness of Minnelide in preventing acute GVHD as compared with posttransplant cyclophosphamide (PTCy). Strikingly, we found Minnelide improved survival, weight loss, and clinical scores in an MHC-mismatched model of aHSCT. These benefits were also apparent in minor MHC-matched aHSCT and xenogeneic HSCT models. Minnelide was comparable to PTCy in terms of survival, GVHD clinical score, and colonic length. Notably, in addition to decreased donor T cell infiltration early after aHSCT, several regulatory cell populations, including Tregs, ILC2s, and myeloid-derived stem cells in the colon were increased, which together may account for Minnelide's GVHD suppression after aHSCT. Importantly, Minnelide's GVHD prevention was accompanied by preservation of graft-versus-tumor activity. As Minnelide possesses anti-acute myeloid leukemia (anti-AML) activity and is being applied in clinical trials, together with the present findings, we conclude that this compound might provide a new approach for patients with AML undergoing aHSCT.

Genetic diversities in wild and cultivated populations of the two closely-related medical plants species, Tripterygium Wilfordii and T. Hypoglaucum (Celastraceae)

BACKGROUND

The sustainable supply of medicinal plants is important, and cultivating and domesticating them has been suggested as an optimal strategy. However, this can lead to a loss of genetic diversity. Tripterygium wilfordii Hook. f. is a medicinal plant commonly used in traditional Chinese medicine, but its wild populations are dwindling due to excessive harvesting. To protect the species and meet the increasing demand, it is urgent to cultivate it on a large scale. However, distinguishing between T. wilfordii and T. hypoglaucum, two similar species with different medicinal properties, is challenging. Therefore, it is crucial to understand the genetic diversity and population structure of these species for their sustainable utilization.

RESULTS

In this study, we investigated the genetic diversity and population structure of the two traditional medicinal semiwoody vines plant species, Tripterygium wilfordii and T. hypoglaucum, including wild and cultivated populations using chloroplast DNA (cpDNA) sequences and microsatellite loci. Our results indicated that the two species maintain a high level of genetic divergence, indicating possible genetic bases for the different contents of bioactive compounds of the two species. T. wilfordii showed lower genetic diversity and less subdivided population structures of both markers than T. hypoglaucum. The potential factors in shaping these interesting differences might be differentiated pollen-to-seed migration rates, interbreeding, and history of population divergence. Analyses of cpDNA and microsatellite loci supported that the two species are genetically distinct entities. In addition, a significant reduction of genetic diversity was observed for cultivated populations of the two species, which mainly resulted from the small initial population size and propagated vegetative practice during their cultivation.

CONCLUSION

Our findings indicate significant genetic divergence between T. wilfordii and T. hypoglaucum. The genetic diversity and population structure analyses provide important insights into the sustainable cultivation and utilization of these medicinal plants. Accurate identification and conservation efforts are necessary for both species to ensure the safety and effectiveness of crude drug use. Our study also highlighted the importance of combined analyses of different DNA markers in addressing population genetics of medicinal plants because of the contrasts of inheritance and rates of gene flow. Large-scale cultivation programs should consider preserving genetic diversity to enhance the long-term sustainability of T. wilfordii and T. hypoglaucum. Our study proposed that some populations showed higher genetic diversity and distinctness, which can be considered with priority for conservation and as the sources for future breeding and genetic improvement.

Dual activity of Minnelide chemosensitize basal/triple negative breast cancer stem cells and reprograms immunosuppressive tumor microenvironment

Triple negative breast cancer (TNBC) subtype is characterized with higher EMT/stemness properties and immune suppressive tumor microenvironment (TME). Women with advanced TNBC exhibit aggressive disease and have limited treatment options. Although immune suppressive TME is implicated in driving aggressive properties of basal/TNBC subtype and therapy resistance, effectively targeting it remains a challenge. Minnelide, a prodrug of triptolide currently being tested in clinical trials, has shown anti-tumorigenic activity in multiple malignancies via targeting super enhancers, Myc and anti-apoptotic pathways such as HSP70. Distinct super-enhancer landscape drives cancer stem cells (CSC) in TNBC subtype while inducing immune suppressive TME. We show that Minnelide selectively targets CSCs in human and murine TNBC cell lines compared to cell lines of luminal subtype by targeting Myc and HSP70. Minnelide in combination with cyclophosphamide significantly reduces the tumor growth and eliminates metastasis by reprogramming the tumor microenvironment and enhancing cytotoxic T cell infiltration in 4T1 tumor-bearing mice. Resection of residual tumors following the combination treatment leads to complete eradication of disseminated tumor cells as all mice are free of local and distant recurrences. All control mice showed recurrences within 3 weeks of post-resection while single Minnelide treatment delayed recurrence and one mouse was free of tumor. We provide evidence that Minnelide targets tumor intrinsic pathways and reprograms the immune suppressive microenvironment. Our studies also suggest that Minnelide in combination with cyclophosphamide may lead to durable responses in patients with basal/TNBC subtype warranting its clinical investigation.

First-in-Human Phase I Study of Minnelide in Patients With Advanced Gastrointestinal Cancers: Safety, Pharmacokinetics, Pharmacodynamics, and Antitumor Activity

BACKGROUND

Minnelide is a water-soluble prodrug of triptolide. Triptolide is an anticancer agent that targets cancer resistance through several mechanisms. Minnelide was evaluated in a phase I study in patients with advanced GI carcinomas to establish the safety, pharmacodynamic, antitumor activity, and recommended phase II dose (RP2D).

PATIENTS AND METHODS

Patients with refractory GI carcinoma and with measurable disease on CT scan were eligible. The study used a 3 + 3 dose-escalation scheme. Due to neutropenia toxicity, 2 dosing schedules were evaluated to determine the RP2D for future studies. Response was assessed using RECIST 1.1 and Choi criteria. Minnelide and triptolide PK were evaluated. Patients who completed the first 28-day treatment cycle without DLTs continued treatment until disease progression or unacceptable toxicity.

RESULTS

Forty-five patients were enrolled (23 pancreatic cancer, 10 colorectal, and the remaining 9 had other GI tumors); 42 patients received at least one dose of Minnelide. Grade ≥ 3 toxicities occurred in 69% of patients, most common neutropenia (38%). 2 patients with severe cerebellar toxicity who had a 2-fold higher triptolide concentration than other participants. ORR was 4%; the disease control rate (DCR) was 54% (15/28). Choi criteria demonstrated a decrease in average tumor density in 57% (16/28) patients.

CONCLUSIONS

This first-in-human, phase I clinical study identified a dose and schedule of Minnelide in patients with refractory GI cancers. The primary toxicity experienced was hematologic. Evidence of efficacy of Minnelide treatment in this group of patients was observed. The DCR ranged from ~2 to 6 months in 14/28 (50%) of evaluable patients. Studies in monotherapy and combination treatments are underway.

Research progress of hexokinase 2 in inflammatory-related diseases and its inhibitors

Hexokinase 2 (HK2) is a crucial enzyme involved in glycolysis, which converts glucose into glucose-6-phosphate and plays a significant role in glucose metabolism. HK2 can mediate glycolysis, which is linked to the release of inflammatory factors. The over-expression of HK2 increases the production of pro-inflammatory cytokines, exacerbating the inflammatory reaction. Consequently, HK2 is closely linked to various inflammatory-related diseases affecting multiple systems, including the digestive, nervous, circulatory, respiratory, reproductive systems, as well as rheumatoid arthritis. HK2 is regarded as a novel therapeutic target for inflammatory-related diseases, and this article provides a comprehensive review of its roles in these conditions. Furthermore, the development of potent HK2 inhibitors has garnered significant attention in recent years. Therefore, this review also presents a summary of potential HK2 inhibitors, offering promising prospects for the treatment of inflammatory-related diseases in the future.

Minnelide Markedly Reduces Proteinuria in Mice with Adriamycin Nephropathy by Protecting Against Podocyte Injury

Minimal change disease (MCD) is the most common cause of idiopathic nephrotic syndrome in children. The current major therapy is hormones for most steroid-sensitive patients. However, many patients have recurrent relapses of the disease and require long-term immunosuppression, leading to significant morbidity due to the side effects of the drugs. Therefore, better drugs need to be urgently explored to treat nephrotic syndrome while avoiding the side effects of drugs. Minnelide, a water-soluble prodrug of triptolide, has been proved to be effective in treating cancers in many clinical trials. This study aimed to investigate the therapeutic effect of minnelide in mice with adriamycin (ADR) nephropathy, its underlying protection mechanisms, and its reproductive toxicity. Minnelide was administered intraperitoneally to 6-8-week female mice with adriamycin nephropathy for 2 weeks, and the urine, blood, and kidney tissues were taken to analyze the therapeutic effect. In addition, we evaluated reproductive toxicity by measuring the levels of gonadal hormones and observing the histological changes in ovaries and testes. Primary mouse podocytes were exposed to puromycin (PAN) to damage the cytoskeleton and induce apoptosis, and then, triptolide was used to evaluate the therapeutic effect and underlying protection mechanisms in vitro. It was observed that minnelide dramatically alleviated proteinuria and apoptosis in mice with adriamycin nephropathy. In vitro, triptolide ameliorated puromycin-induced cytoskeletal rearrangement and apoptosis via reactive oxygen species-mediated mitochondrial pathway. In addition, minnelide caused no reproductive toxicity to male and female mice. The results suggested that minnelide might be a promising drug for nephrotic syndrome.

Therapeutic potential of natural products in inflammation: underlying molecular mechanisms, clinical outcomes, technological advances, and future perspectives

Chronic inflammation is a common underlying factor in many major diseases, including heart disease, diabetes, cancer, and autoimmune disorders, and is responsible for up to 60% of all deaths worldwide. Metformin, statins, and corticosteroids, and NSAIDs (non-steroidal anti-inflammatory drugs) are often given as anti-inflammatory pharmaceuticals, however, often have even more debilitating side effects than the illness itself. The natural product-based therapy of inflammation-related diseases has no adverse effects and good beneficial results compared to substitute conventional anti-inflammatory medications. In this review article, we provide a concise overview of present pharmacological treatments, the pathophysiology of inflammation, and the signaling pathways that underlie it. In addition, we focus on the most promising natural products identified as potential anti-inflammatory therapeutic agents. Moreover, preclinical studies and clinical trials evaluating the efficacy of natural products as anti-inflammatory therapeutic agents and their pragmatic applications with promising outcomes are reviewed. In addition, the safety, side effects and technical barriers of natural products are discussed. Furthermore, we also summarized the latest technological advances in the discovery and scientific development of natural products-based medicine.

A novel triptolide analog downregulates NF-κB and induces mitochondrial apoptosis pathways in human pancreatic cancer

Pancreatic cancer is the seventh leading cause of cancer-related death worldwide, and despite advancements in disease management, the 5 -year survival rate stands at only 12%. Triptolides have potent anti-tumor activity against different types of cancers, including pancreatic cancer, however poor solubility and toxicity limit their translation into clinical use. We synthesized a novel pro-drug of triptolide, (E)-19-[(1'-benzoyloxy-1'-phenyl)-methylidene]-Triptolide (CK21), which was formulated into an emulsion for in vitro and in vivo testing in rats and mice, and used human pancreatic cancer cell lines and patient-derived pancreatic tumor organoids. A time-course transcriptomic profiling of tumor organoids treated with CK21 in vitro was conducted to define its mechanism of action, as well as transcriptomic profiling at a single time point post-CK21 administration in vivo. Intravenous administration of emulsified CK21 resulted in the stable release of triptolide, and potent anti-proliferative effects on human pancreatic cancer cell lines and patient-derived pancreatic tumor organoids in vitro, and with minimal toxicity in vivo. Time course transcriptomic profiling of tumor organoids treated with CK21 in vitro revealed <10 differentially expressed genes (DEGs) at 3 hr and ~8,000 DEGs at 12 hr. Overall inhibition of general RNA transcription was observed, and Ingenuity pathway analysis together with functional cellular assays confirmed inhibition of the NF-κB pathway, increased oxidative phosphorylation and mitochondrial dysfunction, leading ultimately to increased reactive oxygen species (ROS) production, reduced B-cell-lymphoma protein 2 (BCL2) expression, and mitochondrial-mediated tumor cell apoptosis. Thus, CK21 is a novel pro-drug of triptolide that exerts potent anti-proliferative effects on human pancreatic tumors by inhibiting the NF-κB pathway, leading ultimately to mitochondrial-mediated tumor cell apoptosis.

Targeting the Cancer-Neuronal Crosstalk in the Pancreatic Cancer Microenvironment

Pancreatic ductal adenocarcinoma (PDAC) represents one of the most aggressive solid tumors with a dismal prognosis and an increasing incidence. At the time of diagnosis, more than 85% of patients are in an unresectable stage. For these patients, chemotherapy can prolong survival by only a few months. Unfortunately, in recent decades, no groundbreaking therapies have emerged for PDAC, thus raising the question of how to identify novel therapeutic druggable targets to improve prognosis. Recently, the tumor microenvironment and especially its neural component has gained increasing interest in the pancreatic cancer field. A histological hallmark of PDAC is perineural invasion (PNI), whereby cancer cells invade surrounding nerves, providing an alternative route for metastatic spread. The extent of PNI has been positively correlated with early tumor recurrence and reduced overall survival. Multiple studies have shown that mechanisms involved in PNI are also involved in tumor spread and pain generation. Targeting these pathways has shown promising results in alleviating pain and reducing PNI in preclinical models. In this review, we will describe the mechanisms and future treatment strategies to target this mutually trophic interaction between cancer cells to open novel avenues for the treatment of patients diagnosed with PDAC.

STAT3 inhibition enhances gemcitabine sensitivity in pancreatic cancer by suppressing EMT, immune escape and inducing oxidative stress damage

Pancreatic cancer (PC) is a highly-malignant tumor of the digestive system with a very poor prognosis and high mortality. Chemotherapy and PD-1/PD-L1 immune checkpoint blockade are important treatment strategies for advanced PC. However, chemotherapy resistance and poor therapeutic effect of immune checkpoint inhibitors is are the main clinical problems to be solved urgently at present. The effects of combined application of gemcitabine and STAT3 inhibition on the proliferation, apoptosis, migration, and invasion of PC cells (PCCs) were investigated. In addition, oxidative stress (OS), ferroptosis, immune escape, and the epithelial-mesenchymal transition (EMT) were evaluated. STAT3 inhibition with Stattic enhanced the inhibitory activity of gemcitabine on PCC proliferation by regulating the cell cycle. STAT3 inhibition enhanced mitochondrial-dependent apoptosis in gemcitabine-treated PCCs, but did not induce autophagy and ferroptosis. Further study showed that the anti-proliferative and pro-apoptotic effects may be associated with increased OS damage by inactivating Nrf2-HO-1 signaling, as well as DNA damage by inducing the imbalance between ATM andATR-Chk1 pathway. In addition, STAT3 inhibition strengthened gemcitabine-mediated suppression in PCC invasion and migration by antagonizing Smad2/3-dependent EMT. Moreover, the anti-tumorimmuneresponse of gemcitabine was upregulated by Stattic through reducing the expression of PD-L1 and CD47. Mechanistically, combined application of gemcitabine and Stattic suppressed the phosphorylation and nuclear expression of STAT3. Interestingly, the activities of AKT and β-catenin signaling were also regulated, suggesting that drug combination has a broad-spectrum signal regulation effect. STAT3 inhibition enhanced the sensitivity of PCCs to the chemotherapy drug gemcitabine by suppressing EMT and immune escape and inducing OS damage.

Minnelide combined with anti-ANGPTL3-FLD monoclonal antibody completely protects mice with adriamycin nephropathy by promoting autophagy and inhibiting apoptosis

Minimal change disease (MCD) is the common type of nephrotic syndrome (NS) in children. Currently, there is an urgent need to explore new treatments because of the significant side effects of long-term use of glucocorticoids and immunosuppressive drugs and the failure to reduce proteinuria in some patients. Angiopoietin-like protein 3 (Angptl3) is an essential target of NS, and anti-ANGPTL3-FLD monoclonal antibody (mAb) significantly reduces proteinuria in mice with adriamycin nephropathy (AN). However, some proteinuria is persistent. Minnelide, a water-soluble prodrug of triptolide, has been used for the treatment of glomerular disease. Therefore, the present study aimed to investigate whether minnelide combined with mAb could further protect mice with AN and the underlying mechanisms. 8-week-old C57BL/6 female mice were injected with 25 mg/kg of Adriamycin (ADR) by tail vein to establish the AN model. A dose of 200 μg/kg of minnelide or 20 mg/kg of mAb was administered intraperitoneally for the treatment. In vitro, the podocytes were treated with 0.4 μg/mL of ADR for 24 h to induce podocyte injury, and pretreatment with 10 ng/mL of triptolide for 30 min or 100 ng/mL of mAb for 1 h before ADR exposure was used to treat. The results showed that minnelide combined with mAb almost completely ameliorates proteinuria and restores the ultrastructure of the podocytes in mice with AN. In addition, minnelide combined with mAb restores the distribution of Nephrin, Podocin, and CD2AP and reduces the level of inflammatory factors in mice with AN. Mechanistically, minnelide combined with mAb could further alleviate apoptosis and promote autophagy in mice with AN by inhibiting the mTOR signaling pathway. In vitro, triptolide combined with mAb increases the expression of Nephrin, Podocin, and CD2AP, alleviates apoptosis, and promotes autophagy. Overall, minnelide combined with mAb completely protects the mice with AN by promoting autophagy and inhibiting apoptosis.

Recent advances in the development of sialyltransferase inhibitors to control cancer metastasis: A comprehensive review

Metastasis accounts for the majority of cancer-associated mortalities, representing a huge health and economic burden. One of the mechanisms that enables metastasis is hypersialylation, characterized by an overabundance of sialylated glycans on the tumor surface, which leads to repulsion and detachment of cells from the original tumor. Once the tumor cells are mobilized, sialylated glycans hijack the natural killer T-cells through self-molecular mimicry and activatea downstream cascade of molecular events that result in inhibition of cytotoxicity and inflammatory responses against cancer cells, ultimately leading to immune evasion. Sialylation is mediated by a family of enzymes known as sialyltransferases (STs), which catalyse the transfer of sialic acid residue from the donor, CMP-sialic acid, onto the terminal end of an acceptor such as N-acetylgalactosamine on the cell-surface. Upregulation of STs increases tumor hypersialylation by up to 60% which is considered a distinctive hallmark of several types of cancers such as pancreatic, breast, and ovarian cancer. Therefore, inhibiting STs has emerged as a potential strategy to prevent metastasis. In this comprehensive review, we discuss the recent advances in designing novel sialyltransferase inhibitors using ligand-based drug design and high-throughput screening of natural and synthetic entities, emphasizing the most successful approaches. We analyse the limitations and challenges of designing selective, potent, and cell-permeable ST inhibitors that hindered further development of ST inhibitors into clinical trials. We conclude by analysing emerging opportunities, including advanced delivery methods which further increase the potential of these inhibitors to enrich the clinics with novel therapeutics to combat metastasis.

HSP70 Family in Cancer: Signaling Mechanisms and Therapeutic Advances

The 70 kDa heat shock proteins (HSP70s) are a group of highly conserved and inducible heat shock proteins. One of the main functions of HSP70s is to act as molecular chaperones that are involved in a large variety of cellular protein folding and remodeling processes. HSP70s are found to be over-expressed and may serve as prognostic markers in many types of cancers. HSP70s are also involved in most of the molecular processes of cancer hallmarks as well as the growth and survival of cancer cells. In fact, many effects of HSP70s on cancer cells are not only related to their chaperone activities but rather to their roles in regulating cancer cell signaling. Therefore, a number of drugs directly or indirectly targeting HSP70s, and their co-chaperones have been developed aiming to treat cancer. In this review, we summarized HSP70-related cancer signaling pathways and corresponding key proteins regulated by the family of HSP70s. In addition, we also summarized various treatment approaches and progress of anti-tumor therapy based on targeting HSP70 family proteins.

Minnelide combined with Angptl3 knockout completely protects mice with adriamycin nephropathy via suppression of TGF-β1-Smad2 and p53 pathways

Minimal change disease (MCD) is the common type of nephrotic syndrome in children. There is an urgent need to explore new treatment methods as current treatments have many drawbacks and cause significant side effects. Our group found that Angiopoietin-like protein 3 (Angptl3) is closely related to renal disease and Angptl3 knockout significantly alleviated proteinuria in mice with adriamycin nephropathy (AN), however, some proteinuria was still present. Minnelide is a water-soluble prodrug of triptolide which has been used for the treatment of glomerular diseases. Therefore, this study aimed to investigate whether minnelide, combined with Angptl3 knockout, could completely protect mice with AN and its mechanism. AN was induced in B6;129S5 female mice by tail vein injection of 25 mg/kg of Adriamycin (ADR), and treatment with 200 ug/kg/d of minnelide. The results showed that minnelide combined with Angptl3 knockout completely reduced proteinuria and restored the foot processes in mice with AN. Moreover, in Angptl3 knockout mice with AN, minnelide restored the distribution of nephrin, podocin and cd2ap and reduced inflammatory factors (Tumor necrosis factor alpha (TNF-α), Interleukin-6 (IL-6) and Interleukin-1β (IL-1β)). Through RNA sequencing and related experiments, we found minnelide could ameliorate fibrosis and apoptosis by inhibiting TGF-β1-Smad2 and p53 pathways in Angptl3 knockout mice with AN, respectively. In Angptl3 knockout primary podocytes, triptolide alleviates ADR-induced decreases in nephrin, podocin and cd2ap, upregulation of Bax and downregulation of Bcl-2. Overall, our study shows that minnelide combined with Angptl3 knockout completely protects mice with AN by inhibiting the TGF-β1-smad2 and p53 pathways.

Role of epigenetics in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive cancers, associated with poor survival outcomes. Lack of early diagnosis, resistance to conventional therapeutic treatments (including immunotherapy) and recurrence are some of the major hurdles in PDAC and contribute to its poor survival rate. While the risk of genetic predisposition to cancers is widely acknowledged and understood, recent advances in whole-genome and next-generation sequencing techniques have led to the acknowledgment of the role played by epigenetics, especially in PDAC. Epigenetic changes are heritable genetic modifications that influence gene expression without altering the DNA sequence. Epigenetic mechanisms (e.g., DNA methylation, post-translational modification of histone complexes and ncRNA) that result in reversible changes in gene expression are increasingly understood to be responsible for tumor initiation, development and even escape from immune surveillance. Our review seeks to highlight the various components of the epigenetic machinery that are known to be implicated in PDAC initiation and development and the feasibility of targeting these components to identify novel pharmacological strategies that could potentially lead to breakthroughs in PDAC treatment.

Modern Photocatalytic Strategies in Natural Product Synthesis

Modern photocatalysis has proven its generality for the development and functionalization of native functionalities. To date, the field has found broad applications in diverse research areas, including the total synthesis of natural products. This contribution covers recent reports of total syntheses involving as a key step a photocatalytic reaction. Among the selected examples, the photocatalytic processes proceed in a highly chemo-, regio-, and stereoselective manner, thereby allowing the rapid access to structurally complex architectures under light-driven conditions.

A worldwide bibliometric analysis of triptolide research from 1997 to 2021

OBJECTIVES

In recent years, triptolide has received much attention due to its wide range of pharmacological activities. However, no bibliometric studies have been published on triptolide. This study conducted a bibliometric study to provide scientific and insightful information for further research.

METHODS

This study performed a bibliometric study of articles published in the Web of Science database from 1997 to 2021. Based on the keywords used in relation to the title of the article containing the word triptolide, 970 publications were searched for further analysis. We used Microsoft Excel for frequency analysis, VOSviewer and CiteSpace for data visualization, and Rstudio for citation metrics and analysis.

RESULTS

After analysis, standard bibliometric indicators such as the growth of publications, prolific authors and coauthorship, country distributions, preferred journals, most influential institutions and top cited documents were presented in this study.

CONCLUSIONS

According to our findings, the number of triptolide-related publications has been increasing since 2009. China was the largest contributor to triptolide research, followed by the USA. Biomedicine & Pharmacotherapy was the leading journal related to triptolide research. The most productive authors were Zhang LY (China Pharmaceut Univ) and Jiang ZZ (China Pharmaceut Univ). China Pharmaceutical University was the most influential institution in the field of triptolide research. Our findings suggest that the effective use of triptolide in cancer therapy as well as overcoming its multiorgan toxicity to promote its widespread clinical applications are expected to be hot research topics in the future.

A mitochondria-targeted nano-platform for pancreatic cancer therapy

Liposome is a conventional drug delivery system which has been widely used in the pharmacy field. However, its applications are greatly restricted in clinical practice by the disadvantages of cholesterol and nonselective distribution. Herein, a novel platform for anti-tumor drug delivery was developed by incorporating an amphiphilic stachydrine-octadecane conjugate (SS) as the mitochondria-targeting molecule onto the triptolide-liposome surfaces (SS-TP LPs). The polyethylene glycol (PEG) and the suitable particle size (about 133 nm) of liposomes facilitated their stabilities, the long half-life in blood and the escape from the rapid elimination. The SS-TP LPs were internalized and accumulated into the mitochondria of cancer cells in a time-dependent manner, followed by triggering permeabilization of the mitochondrial outer membrane by inhibiting Bcl-2, and then further caused greater cancer cell death via releasing cytochrome C and initiating a cascade of caspase 3 reactions. In the Pan02 tumor-bearing mice, the SS-TP LPs showed significant efficacy in inhibiting tumor growth and reducing tumor size but synchronously exhibited specific mitochondria-targeting and much lower subacute toxicity compared with the free TP and TP LPs. Our study suggests that SS-TP LPs can be a promising anticancer drug delivery system for mitochondria-targeted therapy in pancreatic cancer.

Pharmacologic Targeting of TFIIH Suppresses KRAS-Mutant Pancreatic Ductal Adenocarcinoma and Synergizes with TRAIL

Pancreatic ductal adenocarcinoma (PDAC) typically presents as metastatic disease at diagnosis and remains refractory to treatment. Next-generation sequencing efforts have described the genomic landscape, classified molecular subtypes, and confirmed frequent alterations in major driver genes, with coexistent alterations in KRAS and TP53 correlating with the highest metastatic burden and poorest outcomes. However, translating this information to guide therapy remains a challenge. By integrating genomic analysis with an arrayed RNAi druggable genome screen and drug profiling of a KRAS/TP53 mutant PDAC cell line derived from a patient-derived xenograft (PDCL), we identified numerous targetable vulnerabilities that reveal both known and novel functional aspects of pancreatic cancer biology. A dependence on the general transcription and DNA repair factor TFIIH complex, particularly the XPB subunit and the CAK complex (CDK7/CyclinH/MAT1), was identified and further validated utilizing a panel of genomically subtyped KRAS mutant PDCLs. TFIIH function was inhibited with a covalent inhibitor of CDK7/12/13 (THZ1), a CDK7/CDK9 kinase inhibitor (SNS-032), and a covalent inhibitor of XPB (triptolide), which led to disruption of the protein stability of the RNA polymerase II subunit RPB1. Loss of RPB1 following TFIIH inhibition led to downregulation of key transcriptional effectors of KRAS-mutant signaling and negative regulators of apoptosis, including MCL1, XIAP, and CFLAR, initiating caspase-8 dependent apoptosis. All three drugs exhibited synergy in combination with a multivalent TRAIL, effectively reinforcing mitochondrial-mediated apoptosis. These findings present a novel combination therapy, with direct translational implications for current clinical trials on metastatic pancreatic cancer patients. Significance: This study utilizes functional genetic and pharmacological profiling of KRAS-mutant pancreatic adenocarcinoma to identify therapeutic strategies and finds that TFIIH inhibition synergizes with TRAIL to induce apoptosis in KRAS-driven pancreatic cancer.

Aberrant transcription factors in the cancers of the pancreas

Transcription factors (TFs) are essential for proper activation of gene set during the process of organogenesis, differentiation, lineage specificity. Reactivation or dysregulation of TFs regulatory networks could lead to deformation of organs, diseases including various malignancies. Currently, understanding the mechanism of oncogenesis became necessity for the development of targeted therapeutic strategy for different cancer types. It is evident that many TFs go awry in cancers of the pancreas such as pancreatic ductal adenocarcinoma (PDAC) and pancreatic neuroendocrine neoplasms (PanNENs). These mutated or dysregulated TFs abnormally controls various signaling pathways in PDAC and PanNENs including RTK, PI3K-PTEN-AKT-mTOR, JNK, TGF-β/SMAD, WNT/β-catenin, SHH, NOTCH and VEGF which in turn regulate different hallmarks of cancer. Aberrant regulation of such pathways have been linked to the initiation, progression, metastasis, and resistance in pancreatic cancer. As of today, a number of TFs has been identified as crucial regulators of pancreatic cancer and a handful of them shown to have potential as therapeutic targets in pre-clinical and clinical settings. In this review, we have summarized the current knowledge on the role and therapeutic usefulness of TFs in PDAC and PanNENs.

Minnelide synergizes with conventional chemotherapy by targeting both cancer and associated stroma components in pancreatic cancer

Addition of nab-paclitaxel to gemcitabine offers a survival benefit of only 6 weeks over gemcitabine alone at a cost of increased toxicity in PDAC. The goal of the present study is to evaluate the efficacy of Minnelide, a water-soluble prodrug of triptolide, in combination with the standard of care regimen for chemotherapy with the added advantage of reducing the doses of these drugs to minimize toxicity. Pancreatic cancer cell lines were implanted subcutaneously or orthotopically in athymic nude or C57BL/6J mice. Subsequently, animals were randomized and received saline or minnelide or full dose chemotherapy or low dose chemotherapy or minnelide in combination with low dose chemotherapy. Our results show that a combination of low doses of Minnelide with Gemcitabine + nab-paclitaxel significantly inhibited tumor progression and increased the survival of tumor-bearing mice in comparison with conventional chemotherapy alone. Moreover, combination therapy significantly reduced cancer-related morbidity by decreasing ascites and metastasis and effectively targeted both cancer and the associated stroma. In vitro studies with a combination of low doses of triptolide and paclitaxel significantly decreased the cell viability, increased apoptosis and led to significantly increased M-phase cell cycle arrest in various pancreatic cancer cell lines as compared to either drug alone. Our results show that Minnelide synergizes with conventional chemotherapy leading to a significant reduction in the doses of these toxic drugs, all the while achieving better efficacy in the treatment of PDAC. This combination effectively targeted both the cancer and the associated stromal components of pancreatic cancer.

A Bibliometric Analysis of Triptolide and the Recent Advances in Treating Non-Small Cell Lung Cancer

In recent decades, natural products derived from plants and their derivatives have attracted great interest in the field of disease treatment. Triptolide is a tricyclic diterpene extracted from Tripterygium wilfordii, a traditional Chinese medicine, which has shown excellent therapeutic potential in the fields of immune inflammation and cancer treatment. In this study, 1,106 Web-of-Science-indexed manuscripts and 1,160 Chinese-National-Knowledge-Infrastructure-indexed manuscripts regarding triptolide published between 2011 and 2021 were analyzed, mapping the co-occurrence networks of keywords and clusters using CiteSpace software. The research frontier and development trend were determined by keyword frequency and cluster analysis, which can be used to predict the future research development of triptolide. Non-small cell lung cancer (NSCLC) is most common in lung cancer patients, accounting for about 80% of all lung cancer patients. New evidence suggests that triptolide effectively inhibits the development and metastasis of NSCLC by the induction of apoptosis, reversion of EMT, and regulation of gene expression. Specifically, it acts on NF-κB, MAPKs, P53, Wnt/β-catenin, and microRNAs (miRNAs), signaling pathways and molecular mechanisms. Consequently, this article reviews the research progress of the anti-NSCLC effect of triptolide. In addition, attenuated studies on triptolide and the potential of tumor immunotherapy are also discussed.

Restoring p53 Function in Head and Neck Squamous Cell Carcinoma to Improve Treatments

TP53 mutation is one of the most frequent genetic alterations in head and neck squamous cell carcinoma (HNSCC) and results in an accumulation of p53 protein in tumor cells. This makes p53 an attractive target to improve HNSCC therapy by restoring the tumor suppressor activity of this protein. Therapeutic strategies targeting p53 in HNSCC can be divided into three categories related to three subtypes encompassing WT p53, mutated p53 and HPV-positive HNSCC. First, compounds targeting degradation or direct inhibition of WT p53, such as PM2, RITA, nutlin-3 and CH1iB, achieve p53 reactivation by affecting p53 inhibitors such as MDM2 and MDMX/4 or by preventing the breakdown of p53 by inhibiting the proteasomal complex. Second, compounds that directly affect mutated p53 by binding it and restoring the WT conformation and transcriptional activity (PRIMA-1, APR-246, COTI-2, CP-31398). Third, treatments that specifically affect HPV+ cancer cells by targeting the viral enzymes E6/E7 which are responsible for the breakdown of p53 such as Ad-E6/E7-As and bortezomib. In this review, we describe and discuss p53 regulation and its targeting in combination with existing therapies for HNSCC through a new classification of such cancers based on p53 mutation status and HPV infection.

Celastrol-conjugated chitosan oligosaccharide for the treatment of pancreatic cancer

Celastrol is a promising antitumor drug candidate, but the poor water solubility and cytotoxicity limit its clinical application. Herein, we synthesized a Celastrol (Cel)-chitosan oligosaccharide (CSO) conjugate (Cel-CSO) for drug delivery. Celastrol was conjugated to a CSO backbone via amide bond formation, which was verified by infrared spectrum (IR) analyses. The Cel-CSO contained ∼10 wt% of Celastrol showed excellent aqueous solubility (18.6 mg/mL) in comparation with the parent Celastrol. Cel-CSO significantly inhibited tumor growth, induced apoptosis, and effectively suppressed tumor metastasis in human pancreatic cancer cells (BxPC-3). While the cytotoxicity of Cel-CSO in hepatic cells (HL7702) was lower than that of the free Celastrol. Cel-CSO enhanced the anticancer efficacy, promoted the circulation time of Celastrol, and reduced the subacute toxicity, which indicated that CSO can be a promising Celastrol delivery system for pancreatic cancer therapy.

Deregulation of Transcription Factor Networks Driving Cell Plasticity and Metastasis in Pancreatic Cancer

Pancreatic cancer is a very aggressive disease with 5-year survival rates of less than 10%. The constantly increasing incidence and stagnant patient outcomes despite changes in treatment regimens emphasize the requirement of a better understanding of the disease mechanisms. Challenges in treating pancreatic cancer include diagnosis at already progressed disease states due to the lack of early detection methods, rapid acquisition of therapy resistance, and high metastatic competence. Pancreatic ductal adenocarcinoma, the most prevalent type of pancreatic cancer, frequently shows dominant-active mutations in KRAS and TP53 as well as inactivation of genes involved in differentiation and cell-cycle regulation (e.g. SMAD4 and CDKN2A). Besides somatic mutations, deregulated transcription factor activities strongly contribute to disease progression. Specifically, transcriptional regulatory networks essential for proper lineage specification and differentiation during pancreas development are reactivated or become deregulated in the context of cancer and exacerbate progression towards an aggressive phenotype. This review summarizes the recent literature on transcription factor networks and epigenetic gene regulation that play a crucial role during tumorigenesis.

Identification of potential targets of triptolide in regulating the tumor microenvironment of stomach adenocarcinoma patients using bioinformatics

This study aimed to identify potential pharmacological targets of triptolide regulating the tumor microenvironment (TME) of stomach adenocarcinoma (STAD) patients. A total of 343 STAD cases from The Cancer Genome Atlas (TCGA) were assigned into high- or low-score groups applying Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data (ESTIMATE). Hub genes were identified from differentially expressed genes (DEGs) shared by stromal- and immune-related components in the TME of STAD patients using R software. Cox regression analysis was used to identify genes significantly correlated with STAD patient survival. Triptolide target genes were predicted from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). Top 30 genes filtered by Cytohubba from 734 DEGs were screened as hub genes. Forty-two genes were found to be at high risk for STAD prognosis. Thirty-four targets of triptolide were predicted using the TCMSP database. Importantly, C-X-C chemokine receptor type 4 (CXCR4) was identified as a potential target of triptolide associated with the TME in STAD. Analysis of survival highlighted the association between CXCR4 upregulation with STAD progression and poor prognosis. Gene Set Enrichment Analysis (GSEA) confirmed that genes in the CXCR4- upregulated group had significant enrichment in immune-linked pathways. Additionally, triptolide targets were found to be significantly enriched in CXCR4-related chemokine and cancer-related p53 signaling pathways. Molecular docking demonstrated a high affinity between triptolide and CXCR4. In conclusion, CXCR4 may be a therapeutic target of triptolide in the treatment of STAD patients by modulating the TME.

Reciprocal Regulation of Hippo and WBP2 Signalling-Implications in Cancer Therapy

Cancer is a global health problem. The delineation of molecular mechanisms pertinent to cancer initiation and development has spurred cancer therapy in the form of precision medicine. The Hippo signalling pathway is a tumour suppressor pathway implicated in a multitude of cancers. Elucidation of the Hippo pathway has revealed an increasing number of regulators that are implicated, some being potential therapeutic targets for cancer interventions. WW domain-binding protein 2 (WBP2) is an oncogenic transcriptional co-factor that interacts, amongst others, with two other transcriptional co-activators, YAP and TAZ, in the Hippo pathway. WBP2 was recently discovered to modulate the upstream Hippo signalling components by associating with LATS2 and WWC3. Exacerbating the complexity of the WBP2/Hippo network, WBP2 itself is reciprocally regulated by Hippo-mediated microRNA biogenesis, contributing to a positive feedback loop that further drives carcinogenesis. Here, we summarise the biological mechanisms of WBP2/Hippo reciprocal regulation and propose therapeutic strategies to overcome Hippo defects in cancers through targeting WBP2.

Triptolide improves myocardial fibrosis in rats through inhibition of nuclear factor kappa B and NLR family pyrin domain containing 3 inflammasome pathway

Myocardial fibrosis (MF) is the result of persistent and repeated aggravation of myocardial ischemia and hypoxia, leading to the gradual development of heart failure of chronic ischemic heart disease. Triptolide (TPL) is identified to be involved in the treatment for MF. This study aims to explore the mechanism of TPL in the treatment of MF. The MF rat model was established, subcutaneously injected with isoproterenol and treated by subcutaneous injection of TPL. The cardiac function of each group was evaluated, including LVEF, LVFS, LVES, and LVED. The expressions of ANP, BNP, inflammatory related factors (IL-1β, IL-18, TNF-α, MCP-1, VCAM-1), NLRP3 inflammasome factors (NLRP3, ASC) and fibrosis related factors (TGF-β1, COL1, and COL3) in rats were dete cted. H&E staining and Masson staining were used to observe myocardial cell inflammation and fibrosis of rats. Western blot was used to detect the p-P65 and t-P65 levels in nucleoprotein of rat myocardial tissues. LVED and LVES of MF group were significantly upregulated, LVEF and LVFS were significantly downregulated, while TPL treatment reversed these trends; TPL treatment downregulated the tissue injury and improved the pathological damage of MF rats. TPL treatment downregulated the levels of inflammatory factors and fibrosis factors, and inhibited the activation of NLRP3 inflammasome. Activation of NLRP3 inflammasome or NF-κB pathway reversed the effect of TPL on MF. Collectively, TPL inhibited the activation of NLRP3 inflammasome by inhibiting NF-κB pathway, and improved MF in MF rats.

Network pharmacology of triptolide in cancer cells: implications for transcription factor binding

Background Triptolide is an active natural product, which inhibits cell proliferation, induces cell apoptosis, suppresses tumor metastasis and improves the effect of other therapeutic treatments in several cancer cell lines by affecting multiple molecules and signaling pathways, such as caspases, heat-shock proteins, DNA damage and NF-ĸB. Purpose We investigated the effect of triptolide towards NF-ĸB and GATA1. Methods We used cell viability assay, compare and cluster analyses of microarray-based mRNA transcriptome-wide expression data, gene promoter binding motif analysis, molecular docking, Ingenuity pathway analysis, NF-ĸB reporter cell assay, and electrophoretic mobility shift assay (EMSA) of GATA1. Results Triptolide inhibited the growth of drug-sensitive (CCRF-CEM, U87.MG) and drug-resistant cell lines (CEM/ADR5000, U87.MGΔEGFR). Hierarchical cluster analysis showed six major clusters in dendrogram. The sensitive and resistant cell lines were statistically significant (p = 0.65 × 10^-2) distributed. The binding motifs of NF-κB (Rel) and of GATA1 proteins were significantly enriched in regions of 25 kb upstream promoter of all genes. IPA showed the networks, biological functions, and canonical pathways influencing the activity of triptolide towards tumor cells. Interestingly, upstream analysis for the 40 genes identified by compare analysis revealed ZFPM1 (friend of GATA protein 1) as top transcription regulator. However, we did not observe any effect of triptolide to the binding of GATA1 in vitro. We confirmed that triptolide inhibited NF-κB activity, and it strongly bound to the pharmacophores of IκB kinase β and NF-κB in silico. Conclusion Triptolide showed promising inhibitory effect toward NF-κB, making it a potential candidate for targeting NF-κB.

Recent Advances in Curcumin Treated Non-Small Cell Lung Cancers: An Impetus of Pleiotropic Traits and Nanocarrier Aided Delive ry

Characterized by the abysmal 18% five year survival chances, non-small cell lung cancers (NSCLCs) claim more than half of their sufferers within the first year of being diagnosed. Advances in biomedical engineering and molecular characterization have reduced the NSCLC diagnosis via timid screening of altered gene expressions and impaired cellular responses. While targeted chemotherapy remains a major option for NSCLCs complications, delayed diagnosis, and concurrent multi-drug resistance remain potent hurdles in regaining normalcy, ultimately resulting in relapse. Curcumin administration presents a benign resolve herein, via simultaneous interception of distinctly expressed pathological markers through its pleiotropic attributes and enhanced tumor cell internalization of chemotherapeutic drugs. Studies on NSCLC cell lines and related xenograft models have revealed a consistent decline in tumor progression owing to enhanced chemotherapeutics cellular internalization via co-delivery with curcumin. This presents an optimum readiness for screening the corresponding effectiveness in clinical subjects. Curcumin is delivered to NSCLC cells either (i) alone, (ii) in stoichiometrically optimal combination with chemotherapeutic drugs, (iii) through nanocarriers, and (iv) nanocarrier co-delivered curcumin and chemotherapeutic drugs. Nanocarriers protect the encapsulated drug from accidental and non-specific spillage. A unanimous trait of all nanocarriers is their moderate drug-interactions, whereby native structural expressions are not tampered. With such insights, this article focuses on the implicit NSCLC curative mechanisms viz-a-viz, free curcumin, nanocarrier delivered curcumin, curcumin + chemotherapeutic drug and nanocarrier assisted curcumin + chemotherapeutic drug delivery.