Phellodendrine chloride suppresses proliferation of KRAS mutated pancreatic cancer cells through inhibition of nutrients uptake via macropinocytosis

Autophagy: A potential target for natural products in the treatment of ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disease primarily affecting the mucosa of the colon and rectum. UC is characterized by recurrent episodes, often necessitating lifelong medication use, imposing a significant burden on patients. Current conventional and advanced treatments for UC have the disadvantages of insufficient efficiency, susceptibility to drug resistance, and notable adverse effects. Therefore, developing effective and safe drugs has become an urgent need. Autophagy is an intracellular degradation process that plays an important role in intestinal homeostasis. Emerging evidence suggests that aberrant autophagy is involved in the development of UC, and modulating autophagy can effectively alleviate experimental colitis. A growing number of studies have established that autophagy can interplay with endoplasmic reticulum stress, gut microbiota, apoptosis, and the NLRP3 inflammasome, all of which contribute to the pathogenesis of UC. In addition, a variety of intestinal epithelial cells, including absorptive cells, goblet cells, and Paneth cells, as well as other cell types like neutrophils, antigen-presenting cells, and stem cells in the gut, mediate the development of UC through autophagy. To date, many studies have found that natural products hold the potential to exert therapeutic effects on UC by regulating autophagy. This review focuses on the possible effects and pharmacological mechanisms of natural products to alleviate UC with autophagy as a potential target in recent years, aiming to provide a basis for new drug development.

Tubeimoside-2 Triggers Methuosis in Hepatocarcinoma Cells through the MKK4-p38α Axis

Liver cancer, consisting mainly of hepatocellular carcinoma, is the third leading cause of cancer-related mortality worldwide. Despite advances in targeted therapies, these approaches remain insufficient in meeting the pressing clinical demands. Here, we present a novel alternative that calls for a non-apoptotic program to solve the current dilemma. Specifically, we identified that tubeimoside 2 (TBM-2) could induce methuosis in hepatocellular carcinoma cells, a recently recognized mode of cell death characterized by pronounced vacuolization, necrosis-like membrane disruption, and no response to caspase inhibitors. Further proteomic analysis revealed that TBM-2-driven methuosis is facilitated by the hyperactivation of the MKK4-p38α axis and the boosted lipid metabolism, especially cholesterol biosynthesis. Pharmacological interventions targeting either the MKK4-p38α axis or cholesterol biosynthesis effectively suppress TBM-2-induced methuosis, highlighting the pivotal role of these mechanisms in TBM-2-mediated cell death. Moreover, TBM-2 treatment effectively suppressed tumor growth by inducing methuosis in a xenograft mouse model of hepatocellular carcinoma. Taken together, our findings provide compelling evidence of TBM-2's remarkable tumor-killing effects by inducing methuosis, both in vitro and in vivo. TBM-2 represents a promising avenue for the development of innovative and effective therapies for hepatocellular carcinoma, one that may ultimately offer significant clinical benefits for patients with this devastating disease.

Inhibition of Macropinocytosis Enhances the Sensitivity of Osteosarcoma Cells to Benzethonium Chloride

Osteosarcoma (OS) is a primary malignant tumor of bone. Chemotherapy is one of the crucial approaches to prevent its metastasis and improve prognosis. Despite continuous improvements in the clinical treatment of OS, tumor resistance and metastasis remain dominant clinical challenges. Macropinocytosis, a form of non-selective nutrient endocytosis, has received increasing attention as a novel target for cancer therapy, yet its role in OS cells remains obscure. Benzethonium chloride (BZN) is an FDA-approved antiseptic and bactericide with broad-spectrum anticancer effects. Here, we described that BZN suppressed the proliferation, migration, and invasion of OS cells in vitro and in vivo, but simultaneously promoted the massive accumulation of cytoplasmic vacuoles as well. Mechanistically, BZN repressed the ERK1/2 signaling pathway, and the ERK1/2 activator partially neutralized the inhibitory effect of BZN on OS cells. Subsequently, we demonstrated that vacuoles originated from macropinocytosis and indicated that OS cells might employ macropinocytosis as a compensatory survival mechanism in response to BZN. Remarkably, macropinocytosis inhibitors enhanced the anti-OS effect of BZN in vitro and in vivo. In conclusion, our results suggest that BZN may inhibit OS cells by repressing the ERK1/2 signaling pathway and propose a potential strategy to enhance the BZN-induced inhibitory effect by suppressing macropinocytosis.

Molecular Docking and Intracellular Translocation of Extracellular Vesicles for Efficient Drug Delivery

Extracellular vesicles (EVs), including exosomes, mediate intercellular communication by delivering their contents, such as nucleic acids, proteins, and lipids, to distant target cells. EVs play a role in the progression of several diseases. In particular, programmed death-ligand 1 (PD-L1) levels in exosomes are associated with cancer progression. Furthermore, exosomes are being used for new drug-delivery systems by modifying their membrane peptides to promote their intracellular transduction via micropinocytosis. In this review, we aim to show that an efficient drug-delivery system and a useful therapeutic strategy can be established by controlling the molecular docking and intracellular translocation of exosomes. We summarise the mechanisms of molecular docking of exosomes, the biological effects of exosomes transmitted into target cells, and the current state of exosomes as drug delivery systems.

Antiproliferative Effect of Phellodendron amurense Rupr. Based on Angiogenesis

Phellodendron amurense Rupr. is medicinal plant used for supplemental therapy of various diseases based on their positive biological activities. The aim of this study was evaluated the main metabolite, safety of application and anticancer potential. Berberine was determined by HPLC as main alkaloid. Harmful character was determined by irritation test in ovo. The potential cancerogenic effect was studied in vitro on a cellular level, in ovo by CAM assay and in vivo on whole organism Artemia franciscana. Extract from the bark of Phellodendron amurense showed antiproliferative and antiangiogenic effects. The results of our work showed promising anticancer effects based also on the inhibition of angiogenesis with minimum negative effects.

Pharmacokinetic interaction between rhynchopylline and pellodendrine via CYP450 enzymes and P-gp

CONTEXT

Rhynchopylline and pellodendrine are major extractions of commonly used Chinese medicine in gynaecology. The interaction between these two compounds could affect treatment efficiency and even result in toxicity during their co-administration in gynaecological prescription.

OBJECTIVE

The pharmacokinetic interaction between rhynchopylline and pellodendrine and the potential mechanism were investigated in this study.

MATERIALS AND METHODS

Sprague-Dawley rats were randomly divided into four groups to investigate the pharmacokinetic interaction between rhynchopylline (30 mg/kg) and pellodendrine (20 mg/kg) with single dose of these two drugs as the control. The transport of rhynchopylline was evaluated in the Caco-2 cell model. Additionally, the metabolic stability and the activity of corresponding CYP450 enzymes were assessed in rat liver microsomes.

RESULTS

The pharmacokinetic profile of rhynchopylline was dramatically affected by pellodendrine with the increased area under the pharmacokinetic curve (3080.14 ± 454.54 vs. 1728.08 ± 220.598 μg/L*h), C_max (395.1 ± 18.58 vs. 249.1 ± 16.20 μg/L), prolonged t_1/2 (9.74 ± 2.94 vs. 4.81 ± 0.42 h) and the reduced clearance rate (from 11.39 ± 1.37 to 5.67 ± 1.42 L/h/kg). No significant changes were observed in the pharmacokinetics of pellodendrine. The transport of rhynchopylline was significantly inhibited by pellodendrine with a decreasing efflux ratio (1.43 vs. 1.79). Pellodendrine significantly inhibited the activity of CYP1A2 and CYP2C9 with IC₅₀ values of 22.99 and 16.23 μM, which are critical enzymes responsible for the metabolism of rhynchopylline.

DISCUSSION AND CONCLUSIONS

The adverse interaction between rhynchopylline and pellodendrine draws attention to the co-administration of these two herbs and provides a reference for further investigations with a broader study population.

How to exploit different endocytosis pathways to allow selective delivery of anticancer drugs to cancer cells over healthy cells

It was recently shown that it is possible to exploit the nanoparticle shape to selectively target endocytosis pathways found in cancer and not healthy cells. It is important to understand and compare the endocytosis pathways of nanoparticles in both cancer and healthy cells to restrict the healthy cells from taking up anticancer drugs to help reduce the side effects for patients. Here, the clathrin-mediated endocytosis inhibitor, hydroxychloroquine, and the anticancer drug, doxorubicin, are loaded into the same mesoporous silica nanorods. The use of nanorods was found to restrict the uptake by healthy cells but allowed cancer cells to take up the nanorods via the macropinocytosis pathway. Furthermore, it is shown that the nanorods can selectively deliver doxorubicin to the nucleus of breast cancer cells and to the cytoplasm of pancreatic cancer cells. The dual-drug-loaded nanorods were able to selectively kill the breast cancer cells in the presence of healthy breast cells. This study opens exciting possibilities of targeting cancer cells based on the material shape rather than targeting antibodies.

It was recently shown that it is possible to exploit the nanoparticle shape to selectively target endocytosis pathways found in cancer and not healthy cells.

Lutein induces an inhibitory effect on the malignant progression of pancreatic adenocarcinoma by targeting BAG3/cholesterol homeostasis

Pancreatic adenocarcinoma (PDAC) is a fatal malignancy and patients with PDAC are mostly diagnosed at advanced stages. Lutein is a natural compound that belongs to the non-vitamin A carotenoids family and has presented antitumor effects on multiple cancer types. However, the function of lutein in PDAC and the mechanisms are not reported. Here, we explored the role of lutein in PDAC progression. Bioinformatic analysis identified that lutein is correlated with PDAC. Lutein suppressed the proliferation, migration, and invasion of PANC-1 cells. The upregulated genes in PDAC patients were identified and the overlap analysis predicted BAG3 as one target of lutein. Lutein repressed BAG3 expression and bioinformatics analysis predicted the interaction between lutein and BAG3. The inhibitory effects of lutein on PANC-1 cell proliferation, migration, and invasion are reversed by overexpression of BAG3. GSEA analysis identified that cholesterol homeostasis as one of the downstream signaling pathways of BAG3. In conclusion, lutein induced an inhibitory effect on the malignant progression of PDAC by targeting BAG3/cholesterol homeostasis. Lutein may be applied as a promising candidate for PDAC therapy.

Pancreatic cancer and adaptive metabolism in a nutrient-deficient environment

Despite tremendous progress in the treatment of many cancer types, leading to a significant increase in survival, pancreatic ductal adenocarcinoma (PDAC) is still burdened with high mortality rates (5-year survival rate < 9%) due to late diagnosis, aggressiveness, and a lack of more effective treatment methods. Early diagnosis and new therapeutic approaches based on the adaptive metabolism of the tumor in a nutrient-deficient environment are expected to improve the future treatment of PDAC patients. It was found that blocking selected metabolic pathways related to the local adaptive metabolic activity of pancreatic cancer cells, improving nutrient acquisition and metabolic crosstalk within the microenvironment to sustain proliferation, may inhibit cancer development, increase cancer cell death, and increase sensitivity to other forms of treatment (e.g., chemotherapy). The present review highlights selected metabolic signaling pathways and their regulators aimed at inhibiting the neoplastic process. Particular attention is paid to the adaptive metabolism of pancreatic cancer, including fatty acids, autophagy, macropinocytosis, and deregulated cell-surface glycoproteins, which promotes cancer cell development in an oxygen-deficient and nutrient-poor environment.

Characterization of metabolic fate of phellodendrine and its potential pharmacological mechanism against diabetes mellitus by ultra-high-performance liquid chromatography-coupled time-of-flight mass spectrometry and network pharmacology

RATIONALE

Characterizing the functional mechanism of quality control marker (Q-marker) was of great importance in revealing the primary pharmacological mechanism of herbs or the other complex system, and drug-related metabolites always contribute to the pharmacological functions. Cortex Phellodendri was used as a core herb in the treatment of diabetes mellitus (DM). As a Q-marker of Cortex Phellodendri, the role of phellodendrine in DM was still unclear. Thus, the characterization of phellodendrine-related metabolites in vivo and the subsequent induced functional mechanism exerted great importance in elucidating the anti-DM mechanism of Cortex Phellodendri.

METHODS

An ultra-high-performance liquid chromatography-coupled time-of-flight mass spectrometry (UHPLC/Q-TOF MS) method was developed to profile metabolites of phellodendrine in rats. The potential pharmacological mechanism against DM was predicted by network pharmacology.

RESULTS

A total of 19 phellodendrine-related metabolites were screened out in rats for the first time. Among them, M4, M5, M9, and M12 were regarded as the primary metabolites. Meanwhile, phase I metabolic reactions of hydroxylation, demethylation, and isomerization and phase II reactions of glucuronidation and sulfation occurred to phellodendrine; glucuronidation and hydroxylation were the two main metabolic reactions. Moreover, the potential targets of phellodendrine and three main metabolites (M4, M5, and M12) were predicted by a network pharmacological method, and they mainly shared 52 targets, including PDE5A, CHRNA3, SIGMAR1, F3, ESR1, DRD1, DRD2, DRD3, and DRD4. Furthermore, Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that calcium signaling pathway, cGMP-PKG signaling pathway, and cAMP signaling pathway were regarded as the core mechanism of phellodendrine to treat DM.

CONCLUSION

The metabolic feature of phellodendrine in vivo was revealed for the first time, and its anti-DM mechanism information for further pharmacological validations was also supplied. It also gave a direction to further elucidation of pharmacological mechanism of Cortex Phellodendri in treating DM.

Development of a novel multi-functional integrated bioconjugate that effectively targets K-Ras mutant pancreatic cancer

Folate receptor (FR) overexpression occurs in a variety of cancers, including pancreatic cancer. In addition, enhanced macropinocytosis exists in K-Ras mutant pancreatic cancer. Furthermore, the occurrence of intensive desmoplasia causes a hypoxic microenvironment in pancreatic cancer. In this study, a novel FR-directed, macropinocytosis-enhanced, and highly cytotoxic bioconjugate folate (F)-human serum albumin (HSA)-apoprotein of lidamycin (LDP)-active enediyne (AE) derived from lidamycin was designed and prepared. F-HSA-LDP-AE consisted of four moieties: F, HSA, LDP, and AE. F-HSA-LDP presented high binding efficiency with the FR and pancreatic cancer cells. Its uptake in wild-type cells was more extensive than in K-Ras mutant-type cells. By in vivo optical imaging, F-HSA-LDP displayed prominent tumor-specific biodistribution in pancreatic cancer xenograft-bearing mice, showing clear and lasting tumor localization for 360 h. In the MTT assay, F-HSA-LDP-AE demonstrated potent cytotoxicity in three types of pancreatic cancer cell lines. It also induced apoptosis and caused G2/M cell cycle arrest. F-HSA-LDP-AE markedly suppressed the tumor growth of AsPc-1 pancreatic cancer xenografts in athymic mice. At well-tolerated doses of 0.5 and 1 mg/kg, (i.v., twice), the inhibition rates were 91.2% and 94.8%, respectively (P<0.01). The results of this study indicate that the F-HSA-LDP multi-functional bioconjugate might be effective for treating K-Ras mutant pancreatic cancer.

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We designed and generated a folate receptor-targeted and macropinocytosis-enhanced recombinant protein conjugate.

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F-HSA-LDP displayed highly specific biodistribution and long-lasting tumor accumulation in pancreatic cancer cells.

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F-HSA-LDP-AE induced apoptosis and G2/M cell cycle arrest and markedly suppressed the growth of pancreatic cancer cells.

Phellodendrine promotes autophagy by regulating the AMPK/mTOR pathway and treats ulcerative colitis

To investigate the therapeutic effects of phellodendrine in ulcerative colitis (UC) through the AMPK/mTOR pathway. Volunteers were recruited to observe the therapeutic effects of Compound Cortex Phellodendri Liquid (Huangbai liniment). The main components of Compound Cortex Phellodendri Liquid were analysed via network pharmacology. The target of phellodendrine was further analysed. Caco-2 cells were cultured, and H2 O2 was used to stimulate in vitro cell model. Expression levels of LC3, AMPK, p-AMPK, mTOR and p-mTOR were detected via Western blotting and through immunofluorescence experiments. The therapeutic effects of phellodendrine were analysed via expression spectrum chip sequencing. The sequencing of intestinal flora further elucidated the therapeutic effects of phellodendrine. Compared with the control group, Compound Cortex Phellodendri Liquid could substantially improve the healing of intestinal mucosa. Network pharmacology analysis revealed that phellodendrine is the main component of Compound Cortex Phellodendri Liquid. Moreover, this alkaloid targets the AMPK signalling pathway. Results of animal experiments showed that phellodendrine could reduce the intestinal damage of UC compared with the model group. Findings of cell experiments indicated that phellodendrine treatment could activate the p-AMPK /mTOR signalling pathway, as well as autophagy. Expression spectrum chip sequencing showed that treatment with phellodendrine could promote mucosal healing and reduce inflammatory responses. Results of intestinal flora detection demonstrated that treatment with phellodendrine could increase the abundance of flora and the content of beneficial bacteria. Phellodendrine may promote autophagy by regulating the AMPK-mTOR signalling pathway, thereby reducing intestinal injury due to UC.

Annexin A1 Released in Extracellular Vesicles by Pancreatic Cancer Cells Activates Components of the Tumor Microenvironment, through Interaction with the Formyl-Peptide Receptors

Pancreatic cancer (PC) is one of the most aggressive cancers in the world. Several extracellular factors are involved in its development and metastasis to distant organs. In PC, the protein Annexin A1 (ANXA1) appears to be overexpressed and may be identified as an oncogenic factor, also because it is a component in tumor-deriving extracellular vesicles (EVs). Indeed, these microvesicles are known to nourish the tumor microenvironment. Once we evaluated the autocrine role of ANXA1-containing EVs on PC MIA PaCa-2 cells and their pro-angiogenic action, we investigated the ANXA1 paracrine effect on stromal cells like fibroblasts and endothelial ones. Concerning the analysis of fibroblasts, cell migration/invasion, cytoskeleton remodeling, and the different expression of specific protein markers, all features of the cell switching into myofibroblasts, were assessed after administration of wild type more than ANXA1 Knock-Out EVs. Interestingly, we demonstrated a mechanism by which the ANXA1-EVs complex can stimulate the activation of formyl peptide receptors (FPRs), triggering mesenchymal switches and cell motility on both fibroblasts and endothelial cells. Therefore, we highlighted the importance of ANXA1/EVs-FPR axes in PC progression as a vehicle of intercommunication tumor cells-stroma, suggesting a specific potential prognostic/diagnostic role of ANXA1, whether in soluble form or even if EVs are captured in PC.

Traditional Chinese medicine may be further explored as candidate drugs for pancreatic cancer: A review

Pancreatic cancer is a disease with a high mortality rate. Although survival rates for different types of cancers have improved in recent years, the five-year survival rate of pancreatic cancer stands at 8%. Moreover, the current first-line therapy, gemcitabine, results in low remission rates and is associated with drug resistance problems. Alternative treatments for pancreatic cancer such as surgery, chemotherapy and radiation therapy provide marginal remission and survival rates. This calls for the search of more effective drugs or treatments. Traditional Chinese medicine contains numerous bioactive ingredients some of which show activity against pancreatic cancer. In this review, we summarize the mechanisms of five types of traditional Chinese medicine monomers. In so-doing, we provide new potential drug candidates for the treatment of pancreatic cancer.

Application of advances in endocytosis and membrane trafficking to drug delivery

Multidisciplinary research efforts in the field of drug delivery have led to the development of a variety of drug delivery systems (DDS) designed for site-specific delivery of diagnostic and therapeutic agents. Since efficient uptake of drug carriers into target cells is central to effective drug delivery, a comprehensive understanding of the biological pathways for cellular internalization of DDS can facilitate the development of DDS capable of precise tissue targeting and enhanced therapeutic outcomes. Diverse methods have been applied to study the internalization mechanisms responsible for endocytotic uptake of extracellular materials, which are also the principal pathways exploited by many DDS. Chemical inhibitors remain the most commonly used method to explore endocytotic internalization mechanisms, although genetic methods are increasingly accessible and may constitute more specific approaches. This review highlights the molecular basis of internalization pathways most relevant to internalization of DDS, and the principal methods used to study each route. This review also showcases examples of DDS that are internalized by each route, and reviews the general effects of biophysical properties of DDS on the internalization efficiency. Finally, options for intracellular trafficking and targeting of internalized DDS are briefly reviewed, representing an additional opportunity for multi-level targeting to achieve further specificity and therapeutic efficacy.

Albumin-conjugated drug is irresistible by single gene mutation of endocytic system: Verification by genome-wide CRISPR-Cas9 loss-of-function screens

Albumin-conjugated drugs attain KRAS mutant cancer targeting through KRAS-enhanced macropinocytosis and intensified lysosomal degradation due to reduced neonatal Fc receptor (FcRn) expression. The cytosolic delivery of active payloads relies on endocytosis and subsequent intracellular processing of albumin delivery vehicles, wherein complex regulatory mechanisms and molecular machineries are closely involved. Despite the obvious merit of KRAS targeting, could such an endocytic process involving extra molecular regulators also bring about extra vulnerabilities to albumin-conjugated drugs, particularly, unexpected drug resistance? To assess such risks, here we performed an unbiased drug resistance mechanism comparison in pancreatic cancer, between free triptolide (TP, a potent cytotoxin) and albumin-conjugated TP, using genome-wide CRISPR-Cas9 loss-of-function screens. GTF2H5, a subunit of GTF2H transcription factor complex, was the only hit identified regardless of forms of TP treatment. With drug efficacy tests on GTF2H5 knockout clones, we further concluded that GTF2H5 deficiency conferred drug resistance primarily due to the pharmacological mechanism of action (MoA) of TP. In addition, molecules previously considered to be able to affect endocytosis and intracellular processing were not enriched during the screening with albumin-conjugated TP. With the aid of genome-wide CRISPR-Cas9 loss-of-function screens, we conclude that the pharmacological resistance of the active payload, rather than any potential loss-of-function mutations in endocytic molecular machineries, is the solely crucial drug resistance mechanism of albumin-conjugated drugs.

Modulation of dysregulated cancer metabolism by plant secondary metabolites: A mechanistic review

Several signaling pathways and basic metabolites are responsible for the control of metabolism in both normal and cancer cells. As emerging hallmarks of cancer metabolism, the abnormal activities of these pathways are of the most noticeable events in cancer. This altered metabolism expedites the survival and proliferation of cancer cells, which have attracted a substantial amount of interest in cancer metabolism. Nowadays, targeting metabolism and cross-linked signaling pathways in cancer has been a hot topic to investigate novel drugs against cancer. Despite the efficiency of conventional drugs in cancer therapy, their associated toxicity, resistance, and high-cost cause limitations in their application. Besides, considering the numerous signaling pathways cross-linked with cancer metabolism, discovery, and development of multi-targeted and safe natural compounds has been a high priority. Natural secondary metabolites have exhibited promising anticancer effects by targeting dysregulated signaling pathways linked to cancer metabolism. The present review reveals the metabolism and cross-linked dysregulated signaling pathways in cancer. The promising therapeutic targets in cancer, as well as the critical role of natural secondary metabolites for significant anticancer enhancements, have also been highlighted to find novel/potential therapeutic agents for cancer treatment.