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

Tumor organoids in cancer medicine: from model systems to natural compound screening

CONTEXT

The advent of tissue engineering and biomedical techniques has significantly advanced the development of three-dimensional (3D) cell culture systems, particularly tumor organoids. These self-assembled 3D cell clusters closely replicate the histopathological, genetic, and phenotypic characteristics of primary tissues, making them invaluable tools in cancer research and drug screening.

OBJECTIVE

This review addresses the challenges in developing in vitro models that accurately reflect tumor heterogeneity and explores the application of tumor organoids in cancer research, with a specific focus on the screening of natural products for antitumor therapies.

METHODS

This review synthesizes information from major databases, including Chemical Abstracts, Medicinal and Aromatic Plants Abstracts, ScienceDirect, Google Scholar, Scopus, PubMed and Springer Link. Publications were selected without date restrictions, using terms such as 'organoid', 'natural product', 'pharmacological', 'extract', 'nanomaterial' and 'traditional uses'. Articles related to agriculture, ecology, synthetic work or published in languages other than English were excluded.

RESULTS AND CONCLUSIONS

The review identifies key challenges related to the efficiency and variability of organoid generation and discusses ongoing efforts to enhance their predictive capabilities in drug screening and personalized medicine. Recent studies utilizing patient-derived organoid models for natural compound screening are highlighted, demonstrating the potential of these models in developing new classes of anticancer agents. The integration of natural products with patient-derived organoid models presents a promising approach for discovering novel anticancer compounds and elucidating their mechanisms of action.

Triptolide-based cleavable antibody-drug conjugates for pancreatic cancer

Antibody-drug conjugates (ADCs) have emerged as a highly promising modality for the treatment of various tumors, including pancreatic cancer. Due to the modular nature of ADCs, their efficacy is heavily influenced by the choice of antibody, payload, and linker. Given the therapeutic potential of triptolide for pancreatic cancer, this study aims to harness triptolide as the cytotoxic payload to construct ADCs targeting pancreatic cancer. Silyl ethers were utilized for the first time as cleavable linkers to connect triptolide with an antibody. This is because silyl ethers can be easily synthesized and the rate of drug release can be regulated by modifying the silyl ether groups. The release profile of the resulting linkers was investigated. And considering the balance between cleavage and stability, one silyl ether-based linker was selected to prepare an ADC, named A10. Meanwhile, a traditional dipeptide linker-based ADC, A9, was synthesized for comparison. The ADC A10 demonstrated superior inhibitory effects compared to ADC A9, both in vitro and in vivo. A10 displayed targeted cytotoxicity against cells with high PD-L1 expression and demonstrated a bystander killing effect on cells with low PD-L1 expression. In vivo imaging studies indicated that fluorescently labeled A10 accumulated in tumor regions. Additionally, significant antitumor activities of A10 were observed against Panc 08.13-derived tumor xenografts.

Targeted metabolic engineering of key biosynthetic genes improves triptolide production in Tripterygium wilfordii hairy roots

KEY MESSAGE

The overexpression of key biosynthetic genes involved in triptolide production through a metabolic engineering strategy significantly enhanced triptolide accumulation in Tripterygium wilfordii hairy roots. Triptolide, the representative bioactive compound in Tripterygium wilfordii, is renowned for its potent insecticidal and pharmacological properties. In order to increase the production of triptolide, this study overexpressed several key enzyme genes related to its biosynthesis in T. wilfordii hairy roots. Specifically, the content of triptolide in hairy roots overexpressing TwTPS9 and TwTPS27 individually was found to be 1.60-fold and 1.42-fold that of the control, respectively. Co-expression of both TwTPS9 and TwTPS27 resulted in significant increase in triptolide levels, reaching approximately 2.72 times that of the control. Furthermore, overexpressing TwGGPPS and TwDXS on the basis of the double gene overexpression led to the highest triptolide production, with a yield of 12.83 mg/L, increasing to 3.18-fold compared to the control. This study offers valuable examples into the efficient biosynthesis of triptolide and is expected to lay a foundation for future industrial-scale production by mitigating its resource constraints through metabolic engineering.

RGD peptide/dextran sulfate-based nanocarriers loaded with triptolide for double-targeted apoptosis of both tumor cells and M2-like TAMs in pancreatic cancer therapy

Triptolide (TP) is a promising anti-tumor candidate derived from the herb Tripterygium wilfordii, but its poor water solubility and multi-organ toxicity limit its application. Here, we developed novel nanoparticles (TP-SP@NPs) modified with dextran sulfate and RGD peptide for double-targeted delivery of TP to both tumor cells and pro-tumor macrophages in pancreatic cancer treatment. TP-SP@NPs exhibited suitable particle size (about 98 nm), good stability and controlled release performance. TP-SP@NPs showed high cellular uptake in Pan02 cells and M2 macrophages through αvβ3 integrin-RGD interaction and SR-A-DS interaction, effectively inhibiting tumor growth by triggering apoptosis of these cells. In Pan02 tumor-bearing mice, TP-SP@NPs specifically accumulated at the tumor site and efficiently decreased the number of M2 macrophages, thereby exerting better curative effect on pancreatic cancer and lower systemic toxicity as compared with TP. As a result, TP-SP@NPs had achieved selective anti-tumor effect, good biosafety and great promise in clinical application.

FXR as a pivotal role linking JNK and G0s2 mitigates triptolide-induced hepatotoxicity through the regulation of metabolic disorder of liver

Triptolide (TP), as a principal bioactive compound derived from Tripterygium wilfordii Hook. f., exhibits significant anti-tumor, anti-inflammatory, and immunomodulatory properties. However, the serious adverse reactions and hepatotoxicity of TP limit its clinical application. Therefore, in this study, an intraperitoneal injection was employed to establish a TP-induced hepatotoxicity model, characterized by elevated levels of transaminases (AST and ALT) and metabolic disorders. The administration of the JNK inhibitor SP600125 effectively mitigated the elevated transaminases and inflammation induced by TP. The resistance of SP600125 to metabolic disturbances induced by TP was contingent upon Fxr, as demonstrated through the use of Fxr knockout mice. Supplementation of GW4064 restored the concentrations of bile acids, long-chain fatty acids, and carnitine disrupted by TP. Transcriptomic data suggested that G0s2 was one of the genes most severely disrupted by TP, and the ameliorative effects of SP600125 and GW4064 were accompanied by the upregulation of G0s2. The expression of G0s2 was disrupted by siRNA in vitro, thereby intensifying the cytotoxicity of TP. A comparative analysis of the impact of TP on the G0s2 gene in two mouse models revealed that a smaller reduction in wild-type mice compared to Fxr-/- mice, indicating that Fxr mitigates the inhibitory effect of TP on G0s2. The aberrant JNK/Fxr/G0s2 signaling plays a key role in TP-induced hepatotoxicity. Targeting Fxr might be a potential strategy for alleviating the liver toxicity of TP.

Structural diversity and biological activities of terpenoids derived from Tripterygium wilfordii Hook. f

Terpenoids, a heterogeneous group of natural products, have garnered considerable attention in the field of drug discovery. This is attributed to their vast diversity, intricate structural features, and extensive biological activities. Tripterygium wilfordii Hook. f., a traditional medicinal plant with widespread application in East Asia, is particularly enriched in terpenoids, which can be classified into sesquiterpenoids, diterpenoids, and triterpenoids. The present review provides a comprehensive elaboration of the chemical structures and biological activities of 217 terpenoids isolated from T. wilfordii. The purpose is to shed light on their potential in pharmacological research and to stimulate innovative drug discovery as well as clinical applications. These terpenoids display a broad spectrum of biological activities, such as antitumor, anti - inflammatory, immunosuppressive, and other therapeutic effects. Nevertheless, their clinical application is impeded by issues related to toxicity and poor bioavailability. Future research efforts should be concentrated on exploring effective strategies to alleviate toxicity and enhance drug delivery systems. In addition, in - depth investigation into the structure-activity relationships and the identification of new active constituents are crucial for the development of more potent and safer drugs. This review serves as an exhaustive reference for the discovery and development of novel drugs based on the natural active products of T. wilfordii, providing valuable insights and guidance for researchers in the relevant field.

Triptolide Causes Spermatogenic Disorders by Inducing Apoptosis in the Mitochondrial Pathway of Mouse Testicular Spermatocytes

Triptolide (TP) is a diterpenoid compound extracted from the traditional Chinese medicinal herb Tripterygium wilfordii. It has antitumor and anti-inflammatory effects and stimulates immunity. However, its serious side effects, especially reproductive toxicity, limit its clinical application. This study employed a testicular injury model established by intraperitoneally injecting TP (0.2 mg/kg) in C57BL/6J male mice (age = 7-8 weeks) for 14 days. The control and TP mice's testicular tissues were subjected to transcriptome sequencing to assess potential testicular damage mechanisms. Based on the transcriptome sequencing results and relevant literature reports, further experiments were performed. In addition, to alleviate triptolide-induced testicular damage, we treated the mice with N-acetyl-L-cysteine (NAC). The acquired data revealed that compared with the control mice, the TP-treated mice's testes indicated severe damage. Transcriptome sequencing identified differentially expressed genes that showed enrichment in cell differentiation, apoptotic process, cell cycle, glutathione (GSH) metabolism, and the p53 signaling pathway. Furthermore, TUNEL assays and Western blot analysis showed that in the TP mice's testicular tissues, the spermatocytes had mitochondrial pathway apoptosis as well as abnormal mitochondrial morphology and structure. Triptolide induces oxidative stress in testicular tissue by enhancing pro-oxidative systems and inhibiting antioxidant systems. NAC reduced testicular damage and apoptosis by alleviating TP-induced oxidative stress. This study also employed a GC2 cell line for in-vitro analyses, and the results were consistent with the in vivo experiments. This study provides evidence for alleviating TP's adverse effects on the male reproductive system for better clinical application.

Erianin inhibits the progression of pancreatic cancer by directly targeting AKT and ASK1

BACKGROUND

Pancreatic cancer is a malignant tumor of the digestive tract with a high mortality rate. Erianin has antitumor activity, but the regulatory targets and mechanism of action in pancreatic cancer are unclear. The objective of this study was to evaluate the anti-pancreatic cancer activity of Erianin and explore its underlying mechanisms.

METHODS

A network pharmacology approach was used to investigate the mechanism of action of Erianin in pancreatic cancer cells. Cell proliferation was analyzed using CCK8, colony-formation, and EdU proliferation assays. Cell migration was evaluated through wound healing and transwell assays, as well as determination of the protein expression levels of EMT markers and β-catenin. Apoptosis and the cell cycle were measured using flow cytometry and JC-1 staining, respectively. The protein expression levels of p-Rb, CyclinB1, P21, Cleaved-PARP, and Cleaved-Caspase3 were assessed using western blotting. RNA sequencing (RNA-seq) and bioinformatics analyses were performed to elucidate the mechanism underlying the action of Erianin in pancreatic cancer. Western blotting was used to examine the expression levels of key proteins in the AKT, JNK, and p38 MAPK signaling pathways. Molecular docking and CETSA were used to test hypotheses. The tumor-suppressive ability of Erianin in vivo was assessed using a tumor-bearing assay in nude mice.

RESULTS

Network pharmacology revealed that Erianin inhibited pancreatic cancer through multiple pathways. Erianin significantly inhibited pancreatic cancer cell proliferation and migration while promoting intracellular ROS and inducing apoptosis. Mechanistically, Erianin inhibited pancreatic cancer cell proliferation by regulating the AKT/FOXO1 and ASK1/JNK/p38 MAPK signaling pathways. In vivo experiments showed that Erianin inhibited subcutaneous tumor growth and promoted tumor tissue apoptosis in nude mice.

CONCLUSIONS

The component-target-pathway network revealed that Erianin exerted anti-cancer effects through multiple components, targets, and pathways. Erianin inhibited the proliferation and migration of pancreatic cancer cells and induced apoptosis through the AKT/FOXO1 and ASK1/JNK/p38 MAPK signaling pathways. These results indicate that Erianin is a promising agent for pancreatic cancer treatment.

Therapeutic Potential of Terpenoids in Cancer Treatment: Targeting Mitochondrial Pathways

BACKGROUND

In recent decades, natural compounds have been considered a significant source of new antitumor medicines due to their unique advantages. Several in vitro and in vivo studies have focused on the effect of terpenoids on apoptosis mediated by mitochondria in malignant cells.

RECENT FINDINGS

In this review article, we focused on six extensively studied terpenoids, including sesquiterpenes (dihydroartemisinin and parthenolide), diterpenes (oridonin and triptolide), and triterpenes (betulinic acid and oleanolic acid), and their efficacy in targeting mitochondria to induce cell death. Terpenoid-induced mitochondria-related cell death includes apoptosis, pyroptosis, necroptosis, ferroptosis, autophagy, and necrosis caused by mitochondrial permeability transition. Apoptosis and autophagy interact in meaningful ways. In addition, in view of several disadvantages of terpenoids, such as low stability and bioavailability, advances in research on combination chemotherapy and chemical modification were surveyed.

CONCLUSION

This article deepens our understanding of the association between terpenoids and mitochondrial cell death, presenting a hypothetical basis for the use of terpenoids in anticancer management.

Release of P-TEFb from the Super Elongation Complex promotes HIV-1 latency reversal

The persistence of HIV-1 in long-lived latent reservoirs during suppressive antiretroviral therapy (ART) remains one of the principal barriers to a functional cure. Blocks to transcriptional elongation play a central role in maintaining the latent state, and several latency reversal strategies focus on the release of positive transcription elongation factor b (P-TEFb) from sequestration by negative regulatory complexes, such as the 7SK complex and BRD4. Another major cellular reservoir of P-TEFb is in Super Elongation Complexes (SECs), which play broad regulatory roles in host gene expression. Still, it is unknown if the release of P-TEFb from SECs is a viable latency reversal strategy. Here, we demonstrate that the SEC is not required for HIV-1 replication in primary CD4+ T cells and that a small molecular inhibitor of the P-TEFb/SEC interaction (termed KL-2) increases viral transcription. KL-2 acts synergistically with other latency reversing agents (LRAs) to reactivate viral transcription in several cell line models of latency in a manner that is, at least in part, dependent on the viral Tat protein. Finally, we demonstrate that KL-2 enhances viral reactivation in peripheral blood mononuclear cells (PBMCs) from people living with HIV (PLWH) on suppressive ART, most notably in combination with inhibitor of apoptosis protein antagonists (IAPi). Taken together, these results suggest that the release of P-TEFb from cellular SECs may be a novel route for HIV-1 latency reactivation.

Gentiopicroside inhibits the progression of gastric cancer through modulating EGFR/PI3K/AKT signaling pathway

BACKGROUND

This study was designed to clarify the function and potential mechanism of gentiopicroside (GPS) in regulating the malignant progression of gastric cancer (GC) through in vitro cellular experiments and in vivo animal models.

METHODS

AGS and HGC27 cells were divided into control group and GPS treatment groups (50 µM and 100 µM). Then, the cellular proliferation, colony formation, migration, invasion, and apoptosis were detected, respectively. Transmission electron microscope (TEM) was used to observe the mitochondrial changes, and the mitochondrial membrane potential (MMP) was determined using the JC-1 commercial kit. Network pharmacology analysis was utilized to screen the potential molecule that may be related to the GPS activity on GC cells, followed by validation tests using Western blot in the presence of specific activator. In addition, xenografted tumor model was established using BALB/c nude mice via subcutaneous injection of HGC27 cells, along with pulmonary metastasis model. Then, the potential effects of GPS on the tumor growth and metastasis were detected by immunohistochemistry (IHC) and HE staining.

RESULTS

GPS inhibited the proliferation, invasion and migration of GC cell lines in a dose-dependent manner. Besides, it could induce mitochondrial apoptosis. Epidermal growth factor receptor (EGFR) may be a potential target for GPS action in GC by network pharmacological analysis. GPS inhibits activation of the EGFR/PI3K/AKT axis by reducing EGFR expression. In vivo experiments indicated that GPS induced significant decrease in tumor volume, and it also inhibited the pulmonary metastasis. For the safety concerns, GPS caused no obvious toxicities to the heart, liver, spleen, lung and kidney tissues. IHC staining confirmed GPS downregulated the activity of EGFR/PI3K/AKT.

CONCLUSIONS

Our investigation demonstrated for the first time that GPS could inhibit GC malignant progression by targeting the EGFR/PI3K/AKT signaling pathway. This study indicated that GPS may be serve as a safe anti-tumor drug for further treatment of GC.