Antitumor effect of polyphyllin I (PPI) on colorectal cancer: Evidence from patient-derived organoids and Notch signaling suppression.

Colorectal cancer (CRC) is a malignant tumor with a high incidence, ranking first among gastrointestinal malignancies. We investigated the impact of polyphyllin I (PPI), a natural compound found in Paris polyphylla, on CRC. PPI has been documented to exhibit anticancer activity against various tumors. This study aimed to assess the effects of PPI on colorectal cancer and explore its potential mechanisms. Our research demonstrated that PPI inhibited proliferation, promoted apoptosis, and induced G2 cell-cycle arrest in a dose-dependent manner. Additionally, our results indicated that PPI suppressed Notch signaling by downregulating the Notch1 receptor, its ligand Jagged1, and the downstream target Hes1 expression. Furthermore, we confirmed the antitumor effect of PPI on patient-derived organoids. In conclusion, our study indicates that PPI impedes the growth of colon cancer by suppressing the Notch signaling pathway.

Polyphyllin I exerts anti-hepatocellular carcinoma activity by targeting ZBTB16 to activate the PPARγ/RXRα signaling pathway.

BACKGROUND: Studies have reported that polyphyllin I (PPI) had effective anti-tumor activity against hepatocellular carcinoma (HCC). However, the precise molecular mechanism of this action and the direct target remain unclear. The aim of this study was to discover the molecular targets and the exact mechanism of PPI in the treatment of HCC. METHODS: Various HCC cells and Zebrafish xenotransplantation models were used to examine the efficacy of PPI against HCC. A proteome microarray, surface plasmon resonance (SPR) analysis, small molecule transfection, and molecular docking were conducted to confirm the direct binding targets of PPI. Transcriptome and Western blotting were then used to determine the exact responding mechanism. Finally, the anticancer effect and its precise mechanism, as well as the safety of PPI, were verified using a mouse tumor xenograft study. RESULTS: The results demonstrated that PPI had significant anticancer activity against HCC in both in vitro studies of two cells and the zebrafish model. Notably, PPI selectively enhanced the action of the Zinc finger and BTB domain-containing 16 (ZBTB16) protein by directly binding to it. Furthermore, specific knockdown of ZBTB16 markedly attenuated PPI-dependent inhibition of HCC cell proliferation and migration caused by overexpression of the gene. The transcriptome and Western blotting also confirmed that the interaction between ZBTB16 and PPI also activated the PPARγ/RXRα pathway. Finally, the mouse experiments confirmed the efficacy and safety of PPI to treat HCC. CONCLUSIONS: Our results indicate that ZBTB16 is a promising drug target for HCC and that PPI as a potent ZBTB16 agonist has potential as a therapeutic agent against HCC by regulating the ZBTB16/PPARγ/RXRα signaling axis.

Polyphyllin I Mitigated IL-1ß-Induced Chondrocytes Damage through Downregulating TWIST1 Expression.

BACKGROUND: Osteoarthritis (OA) is a chronic joint disease characterized by the degradation of articular cartilage. Polyphyllin I (PPI) has anti-inflammatory effects in many diseases. However, the mechanism of PPI in OA remains unclear.

Polyphyllin I ameliorates gefitinib resistance and inhibits the VEGF/VEGFR2/p38 pathway by targeting HIF-1a in lung adenocarcinoma.

BACKGROUND: Lung adenocarcinoma (LUAD) is the most common pathological type of lung cancer. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have been administered as the first-line therapy for patients with EGFR mutations in LUAD, but it is almost inevitable that resistance to EGFR-TKIs therapy eventually arises. Polyphyllin I (PPI), derived from Paris polyphylla rhizomes, has been shown to have potent anti-cancer properties in a range of human cancer types including LUAD. However, the role of PPI in gefitinib resistance and the underlying mechanism remain elusive. PURPOSE: To evaluate the antitumor impacts of PPI on gefitinib resistance cells and investigate its molecular mechanism. METHODS: CCK-8, wound healing, transwell assay, and xenograft model were performed to determine the anti-cancer effects of PPI as well as its ability to overcome gefitinib resistance. Immunoblotting, co-immunoprecipitation, phospho-RTK antibody array, qRT-PCR, and immunofluorescence were utilized to explore the mechanism by which PPI overrides gefitinib resistance. RESULTS: PPI inhibited cell survival, growth, and migration/invasion in both gefitinib-sensitive (PC9) and -resistant (PC9/GR) LUAD cells (IC50 at 2.0 µM). Significantly, treatment with PPI at 1.0 µM resensitized the resistant cells to gefitinib. Moreover, cell-derived xenograft experiments revealed that the combination of PPI and gefitinib overcame gefitinib resistance. The phospho-RTK array and immunoblotting analyses showed PPI significant inhibition of the VEGFR2/p38 pathway. In addition, molecular docking suggested the interaction between PPI and HIF-1α. Mechanistically, PPI reduced the protein expression of HIF-1α in both normoxia and hypoxia conditions by triggering HIF-1α degradation. Moreover, HIF-1α protein but not mRNA level was elevated in gefitinib-resistant LUAD. We further demonstrated that PPI considerably facilitated the binding of HIF-1α to VHL. CONCLUSIONS: We present a novel discovery demonstrating that PPI effectively counteracts gefitinib resistance in LUAD by modulating the VEGF/VEGFR2/p38 pathway. Mechanistic investigations unveil that PPI facilitates the formation of the HIF-1α /VHL complex, leading to the degradation of HIF-1α and subsequent inhibition of angiogenesis. These findings uncover a previously unidentified mechanism governing HIF-1α expression in reaction to PPI, providing a promising method for therapeutic interventions targeting EGFR-TKI resistance in LUAD.

Polyphyllin I alleviates neuroinflammation after cerebral ischemia-reperfusion injury via facilitating autophagy-mediated M2 microglial polarization.

Microglial activation and polarization play a central role in poststroke inflammation and neuronal damage. Modulating microglial polarization from pro-inflammatory to anti-inflammatory phenotype is a promising therapeutic strategy for the treatment of cerebral ischemia. Polyphyllin I (PPI), a steroidal saponin, shows multiple bioactivities in various diseases, but the potential function of PPI in cerebral ischemia is not elucidated yet. In our study, the influence of PPI on cerebral ischemia-reperfusion injury was evaluated. Mouse middle cerebral artery occlusion (MCAO) model and oxygen-glucose deprivation and reoxygenation (OGD/R) model were constructed to mimic cerebral ischemia-reperfusion injury in vivo and in vitro. TTC staining, TUNEL staining, RT-qPCR, ELISA, flow cytometry, western blot, immunofluorescence, hanging wire test, rotarod test and foot-fault test, open-field test and Morris water maze test were performed in our study. We found that PPI alleviated cerebral ischemia-reperfusion injury and neuroinflammation, and improved functional recovery of mice after MCAO. PPI modulated microglial polarization towards anti-inflammatory M2 phenotype in MCAO mice in vivo and post OGD/R in vitro. Besides, PPI promoted autophagy via suppressing Akt/mTOR signaling in microglia, while inhibition of autophagy abrogated the effect of PPI on M2 microglial polarization after OGD/R. Furthermore, PPI facilitated autophagy-mediated ROS clearance to inhibit NLRP3 inflammasome activation in microglia, and NLRP3 inflammasome reactivation by nigericin abolished the effect of PPI on M2 microglia polarization. In conclusion, PPI alleviated post-stroke neuroinflammation and tissue damage via increasing autophagy-mediated M2 microglial polarization. Our data suggested that PPI had potential for ischemic stroke treatment.

Polyphyllin I induces rapid ferroptosis in acute myeloid leukemia through simultaneous targeting PI3K/SREBP-1/SCD1 axis and triggering of lipid peroxidation.

Acute myeloid leukemia (AML) is a malignant disease that is difficult to completely cure. Polyphyllin I (PPI), a steroidal saponin isolated from Paris polyphylla, has exhibited multiple biological activities. Here, we discovered the superior cytotoxicity of PPI on AML cells MOLM-13 with an IC50 values of 0.44 ± 0.09 µM. Mechanically, PPI could cause ferroptosis via the accumulation of intracellular iron concentration and triggering lipid peroxidation. Interestingly, PPI could induced stronger ferroptosis in a short time of about 6 h compared to erastin. Furthermore, we demonstrate that PPI-induced rapid ferroptosis is due to the simultaneous targeting PI3K/SREBP-1/SCD1 axis and triggering lipid peroxidation, and PI3K inhibitor Alpelisib can enhance the activity of erastin-induced ferroptosis. Molecular docking simulations and kinase inhibition assays demonstrated that PPI is a PI3K inhibitor. In addition, PPI significantly inhibited tumor progression and prolonged mouse survival at 4 mg/kg with well tolerance. In summary, our study highlights the therapeutic potential of PPI for AML and shows its unique dual mechanism.

Paris polyphylla ethanol extract and polyphyllin I ameliorate adenomyosis by inhibiting epithelial-mesenchymal transition.

BACKGROUND: The active ingredients of the Chinese medical herb Paris polyphylla, P. polyphylla ethanol extract (PPE) and polyphyllin I (PPI), potentially inhibit epithelial-mesenchymal transition (EMT) in tumors. However, the roles of these ingredients in inhibiting EMT in adenomyosis (AM) remain to be explored. PURPOSE: The primary goal of the study was to uncover the underlying molecular processes through which PPE and PPI suppress EMT in AM, alongside assessing the safety profiles of these substances. METHODS: To assess the suppressive impact of PPE on adenomyosis-derived cells (AMDCs), we employed Transwell and wound healing assays. The polyphyllins (PPI, PPII, PPVII) contained in PPE were characterized using high-performance liquid chromatography (HPLC). Then, bioinformatics techniques were performed to pinpoint potential PPI targets that could be effective in treating AM. Immunoblotting was used to verify the key proteins and pathways identified via bioinformatics. Furthermore, we examined the efficacy of PPE and PPI in treating Institute of Cancer Research (ICR) mice with AM by observing the morphological and pathological features of the uterus and performing immunohistochemistry. In addition, we assessed safety by evaluating liver, kidney and spleen pathologic features and serum test results. RESULTS: Three major polyphyllins of PPE were revealed by HPLC, and PPI had the highest concentration. In vitro experiments indicated that PPE and PPI effectively prevent AMDCs invasion and migration. Bioinformatics revealed that the primary targets E-cadherin, N-cadherin and TGFß1, as well as the EMT biological process, were enriched in PPI-treated AM. Immunoblotting assays corroborated the hypothesis that PPE and PPI suppress the TGFß1/Smad2/3 pathway in AMDCs to prevent EMT from progressing. Additionally, in vivo studies showed that PPE (3 mg/kg and 6 mg/kg) and PPI (3 mg/kg and 6 mg/kg), successfully suppressed the EMT process through targeting the TGFß1/Smad2/3 signaling pathway. Besides, it was observed that lower doses of PPE (3 mg/kg) and PPI (3 mg/kg) exerted minimal effects on the liver, kidneys, and spleen. CONCLUSIONS: PPE and PPI efficiently impede the development of EMT by inhibiting the TGFß1/Smad2/3 pathway, revealing an alternative pathway for the pharmacological treatment of AM.

Polyphyllin I enhances tumor necrosis factor-related apoptosis-inducing ligand-induced inhibition of human osteosarcoma cell growth downregulating the Wnt/ß-catenin pathway.

OBJECTIVE: To investigate the synergistic effects of polyphyllin I (PPI) combined with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) on the growth of osteosarcoma cells through downregulating the Wnt/ß-catenin signaling pathway. METHODS: Cell viability, apoptosis and cell cycle distribution were examined using cell counting kit-8 and flow cytometry assays. The morphology of cancer cells was observed with inverted phase contrast microscope. The migration and invasion abilities were examined by xCELLigence real time cell analysis DP system and transwell assays. The expressions of poly (adenosine diphosphate-ribose) polymerase, C-Myc, Cyclin B1, cyclin-dependent kinases 1, N-cadherin, Vimentin, Active-ß-catenin, ß-catenin, p-glycogen synthase kinase 3ß (GSK-3ß) and GSK-3ß were determined by Western blotting assay. RESULTS: PPI sensitized TRAIL-induced decrease of viability, migration and invasion, as well as increase of apoptosis and cell cycle arrest of MG-63 and U-2 OS osteosarcoma cells. The synergistic effect of PPI with TRAIL in inhibiting the growth of osteosarcoma cells was at least partially realized through the inactivation of Wnt/ß-catenin signaling pathway. CONCLUSION: The combination of PPI and TRAIL is potentially a novel treatment strategy of osteosarcoma.

Polyphyllin I inhibits endometriosis in vitro by inducing apoptosis and autophagy via the inactivation of AKT/mTOR signalling pathway.

Previous research has indicated that Polyphyllin I (PPI) possesses potent anticancer properties. However, its impact on endometriosis remains unexplored. This study aims to investigate the inhibitory effects of PPI on ectopic endometrial stromal cells (EESCs). The CCK-8 and flow cytometry results respectively showed that the cell viability of EESCs decreased and the number of apoptotic cells increased in a dosage dependent of PPI. Wound healing and transwell assays demonstrated a notable reduction in cell motility and migration ability in the PPI group. Moreover, the Western blot analysis revealed a decrease in p62 levels and an increase in LC3-II expression following PPI administration. Additionally, the protein levels of p-Akt and p-mTOR were observed to decrease with increasing concentrations of PPI, indicating the potential of PPI to induce autophagy in EESCs through modulation of the Akt/mTOR signalling pathway. Consequently, PPI holds promise as a targeted therapeutic agent for the management of endometriosis.

Polyphyllin I attenuates the invasion and metastasis via downregulating GRP78 in drug-resistant hepatocellular carcinoma cells.

Drug resistance to chemotherapy agents presents a major obstacle to the effective treatment of hepatocellular carcinoma (HCC), a common type of liver cancer. Increasing evidence indicates a link between drug resistance and the recurrence of HCC. Polyphyllin I (PPI), a promising pharmaceutical candidate, has shown potential therapeutic advantages in the treatment of sorafenib-resistant hepatocellular carcinoma (SR-HCC cells). In this study, we sought to investigate the mechanism underlying the inhibitory effect of PPI on the invasion and metastasis of SR-HCC cells. Our in vitro studies included scratch wound-healing migration assays and transwell assays to examine PPI's effect on HCC cell migration and invasion. Flow cytometry was employed to analyze the accumulation or efflux of chemotherapy drugs. The results of these experiments demonstrated that PPI increased the susceptibility of HCC to sorafenib while inhibiting SR-HCC cell growth, migration, and invasion. Molecular docking analysis revealed that PPI exhibited a higher binding affinity with GRP78. Western blot analysis and immunofluorescence experiments showed that PPI reduced the expression of GRP78, E-cadherin, N-cadherin, Vimentin, and ABCG2 in SR-HCC cells. Interference with and overproduction of GRP78 in vitro impacted the proliferation, migration, invasion, and metastasis of HCC cells. Further examination revealed that PPI hindered the expression of GRP78 protein, resulting in a suppressive effect on SR-HCC cell migration and invasion. Histological examination of tumor tissue substantiated that administering PPI via gavage to HepG2/S xenograft nude mice inhibited tumor growth and significantly reduced tumor size, as evidenced by xenograft experiments involving nude mice. Hematoxylin and eosin (HE) staining of tumor tissue specimens, along with immunohistochemistry (IHC), were conducted to evaluate the expression levels of Ki67, GRP78, N-cadherin, Vimentin, and ABCG2. The results indicated that PPI administration decreased the levels of proteins associated with metastasis and markers of drug resistance in tumor tissues, impeding tumor growth and spread. Overall, our findings demonstrated that PPI effectively suppressed the viability, proliferation, invasion, and metastasis of SR-HCC cells both in vitro and in vivo by modulating GRP78 activity. These findings provide new insights into the mechanism of PPI inhibition of SR-HCC cell invasion and metastasis, highlighting PPI as a potential treatment option for sorafenib-resistant HCC.

MiR-124-3p mediates gastric cancer cell ferroptosis induced by an anti-cancer drug polyphyllin I.

Background: Ferroptosis is an emerging type of regulated cell death and associated with antitumoral therapy, while some microRNAs have been shown to regulate the tumorigenesis and cancer progression. Meanwhile, polyphyllin I (PPI) has exhibited antitumoral effects by promoting cancer cell apoptosis and ferroptosis. However, it is unclear whether PPI induces cancer cell ferroptosis by regulating microRNAs. Methods: We used two gastric cancer cell lines (AGS and MKN-45) to set up a tumor model of the nude mice, which were then treated daily with PPI to measure the cancer growth in vitro and in vivo. Ferroptosis was measured using immunofluorescence staining and flow cytometric analysis according to levels of intracellular ROS, lipid ROS and ferrous ions. Moreover, NRF2 expression was measured by Western blotting. In some experiments, the mimics or inhibitors of miR-124-3p were used to further confirm its involvement in PPI-induced cancer cell ferroptosis. Results: Here we found that miR-124-3p mediated cancer ferroptosis and tumor repression induced by PPI since PPI increased miR-124-3p expression in gastric cancer cells and promoted their ferroptosis, whereas inhibition of miR-124-3p mostly abolished the effects of PPI on tumor growth, ferroptosis and NRF2 expression. Moreover, miR-124-3p mimics promoted cancer cell ferroptosis by downregulating NRF2 through directly targeting 3'-UTR region of NRF2, confirming a role for miR-124-3p in regulating PPI-induced ferroptosis. Conclusion: PPI exerts its antitumoral effects on the gastric cancer by promoting cell ferroptosis via regulating miR-124-3p. Our findings have clinical implications for cancer chemotherapy.

Polyphyllin I, a strong antifungal compound against Candida albicans.

This study was performed to explore the antifungal and antibiofilm effects of polyphyllin I (PPI) on Candida albicans. Microdilution assay was performed to determine the minimal inhibitory concentrations (MIC) of PPI against Candida species. Adhesion assay, hyphal growth assay, biofilm formation, and development were used to test the impacts of PPI on C. albicans virulence factors. Propidium iodide staining was performed to test whether the permeability of cell membrane was influenced by PPI. PPI showed significant antifungal activities against several Candida species, with MIC below or equal to 6.25 µM. PPI also inhibited the adhesion to polystyrene surfaces, hyphal growth, and biofilm formation. PPI significantly increased the permeability of C. albicans cell membrane. In sum, PPI can suppress the planktonic growth and biofilm of C. albicans and its mechanism involves the increased permeability of cell membrane.

Polyphyllin I suppressed the apoptosis of intervertebral disc nucleus pulposus cells induced by IL-1ß by miR-503-5p/Bcl-2 axis.

BACKGROUND: There are no studies that have shown the role and underlying mechanism of Polyphyllin I (PPI)-mediated anti-apoptosis activity in nucleus pulposus cells (NPCs). The research aimed to evaluate the effects of PPI in interleukin (IL)-1ß-induced NPCs apoptosis in vitro. METHODS: Cell Counting Kit-8 (CCK-8) assay was used to detect cell viability, and cell apoptosis was evaluated by double-stained flow cytometry (FITC Annexin V/PI). The expression of miR-503-5p was quantified by real-time quantitative PCR (qRT-PCR), and the expression of Bcl-2, Bax, and cleaved caspase-3 was quantified by Western blot. Dual-luciferase reporter gene assay was used to detect the targeting relationship between miR-503-5p and Bcl-2. RESULTS: PPI at 40 µg·mL-1 markedly promoted the viability of NPCs (P < 0.01). Also, PPI inhibited apoptosis and reduction in proliferative activity induced by IL-1ß in the NPCs (P < 0.001, 0.01). PPI treatment significantly inhibited the expression of apoptosis-related protein Bax, cleaved caspase-3 (P < 0.05, 0.01), and enhanced the level of anti-apoptotic protein Bcl-2 (P < 0.01). The proliferative activity of NPCs was significantly decreased and the apoptosis rate of NPCs was increased under IL-1ß treatment (P < 0.01, 0.001). Moreover, miR-503-5p was highly expressed in IL-1ß-induced NPCs (P < 0.001). Furthermore, the effect of PPI on NPCs viability and apoptosis in IL-1ß treatment was dramatically reversed by the overexpression of miR-503-5p (P < 0.01, 0.01). The targeted binding of miR-503-5p to the 3'UTR of Bcl-2 mRNA was confirmed by dual-luciferase reporter gene assays (P < 0.05). In further experiments, compared with miR-503-5p mimics, the effects of PPI on IL-1ß-induced NPCs viability and apoptosis were greatly reversed by the co-overexpression of miR-503-5p and Bcl-2 (P < 0.05, 0.05). CONCLUSION: PPI suppressed the apoptosis of intervertebral disk (IVD) NPCs induced by IL-1ß via miR-503-5p/Bcl-2 molecular axis.

Corrigendum: Polyphyllin I suppresses the gastric cancer growth by promoting cancer cell ferroptosis.

[This corrects the article DOI: 10.3389/fphar.2023.1145407.].

Polyphyllin I suppresses the gastric cancer growth by promoting cancer cell ferroptosis.

Background: Ferroptosis is a new form of regulated cell death characterized by the accumulation of iron-dependent lipid peroxides and membrane damages. Recent studies have identified an important role for cancer cell ferroptosis in antitumor therapy. On the other hand, polyphyllin I (PPI) has been reported to exert antitumor effects on some types of cancers. However, it remains unknown whether or not PPI regulates cancer cell ferroptosis. Methods: Two types of human gastric cancer cells (AGS and MKN-45) were used to establish tumor xenograft models in nude mice that were treated with polyphyllin I (PPI) to observe tumor growth, while cells also were cultured for in vitro studies. Ferroptosis, based on the intracellular ROS/lipid ROS production and accumulation of ferrous ions, was detected using a fluorescence microscope and flow cytometer, while the expression of NRF2/FTH1 was measured using Western blotting assays. Results: Here we found that PPI inhibited the gastric cancer growth in vivo and in vitro while increasing the intracellular reactive oxygen species (ROS)/lipid peroxides and ferrous ions in the gastric cancer cells. PPI also decreased the levels of nuclear factor erythroid 2-related factor 2 (NRF2) and ferritin heavy chain 1 (FTH1) in gastric cancer cells in vitro. Moreover, liproxstain-1, an inhibitor of cell ferroptosis, mostly reversed the cell ferroptosis and tumor growth arrest induced by PPI. Finally, the effects of PPI on cancer cell ferroptosis were diminished by the overexpression of NRF2. Conclusion: For the first time, our results have demonstrated that PPI exerts its antitumor activity on the gastric cancer by, at least partially, inducing cancer cell ferroptosis via regulating NRF2/FTH1 pathway. These findings may be implicated for clinical replacement therapy of the gastric cancer.

Polyphyllin I induces apoptosis and autophagy in temozolomide-resistant glioma via modulation of NRF2 and MAPK-signaling activation.

Glioma is the most prevailing main malignant neoplasm of the central nervous system with a miserable prognosis. Temozolomide is the first-line chemotherapy drug for glioma, but its drug resistance reduces temozolomide's clinical efficacy and becomes the principal cause of the failure of glioma chemotherapy. Polyphyllin I (PPI), an active component in Rhizoma Paridis, demonstrates favorable therapeutic actions in diverse malignant neoplasms. Its effect on temozolomide-resistant glioma, however, has not yet been characterized. Here, we demonstrated that polyphyllin I inhibited the proliferation of temozolomide-resistant glioma cell in a concentration-dependent manner. Further, we found that polyphyllin I had a direct effect on temozolomide-resistant glioma tumor cells and promote reactive oxygen species (ROS)-dependent apoptosis and autophagy via mitogen-activated protein kinase (MAPK)-signaling (p38-JNK) pathway. Mechanistically, we showed that polyphyllin I downregulate the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) pathway, indicating that polyphyllin I may be an expected therapeutic strategy for patients with temozolomide-resistant gliomas.

Transforming Cold Tumors into Hot Ones with a Metal-Organic Framework-Based Biomimetic Nanosystem for Enhanced Immunotherapy.

Immunotherapy has revolutionized the landscape in clinical tumor therapy, although the response rates in "cold" tumors are relatively low owing to the complex tumor microenvironment (TME). Cyclic guanosine monophosphate-adenosine monophosphate synthase/stimulator of interferon genes (cGAS/STING) pathway-inducing agents can reprogram the TME; however, their applications remain underutilized. Herein, we engineered a facile manganese-based metal-organic framework (Mn-MOF) encapsulating polyphyllin I (PPI) and coated it with red blood cell (RBC) membranes (RBC@Mn-MOF/PPI) that enhanced the cGAS/STING-mediated antitumor immunity. RBC@Mn-MOF/PPI was engineered by camouflaging it with a biomimetic RBC membrane for prolonged blood circulation and immune escape, which was also extended with TME-sensitive properties for triggering the release of PPI and Mn2+ to remodel the suppressive TME and augment antitumor immune responses. Furthermore, RBC@Mn-MOF/PPI helped transform cold tumors into "hot" ones by activating immune cells, as evidenced via dendritic cell maturation, cytotoxic T lymphocyte infiltration, and natural killer cell recruitment, thereby targeting primary and abscopal tumors and lung metastatic nodules. Therefore, our engineered nanosystem represents a novel strategy to transform immunologically "cold" tumors into "hot" ones by activating the cGAS/STING pathway, thereby addressing the major challenges associated with immunotherapy.

Therapeutic effects on cancer of the active ingredients in rhizoma paridis.

Cancer is a major threat to human health, with high mortality and a low cure rate, continuously challenging public health worldwide. Extensive clinical application of traditional Chinese medicine (TCM) for patients with poor outcomes of radiotherapy and chemotherapy provides a new direction in anticancer therapy. Anticancer mechanisms of the active ingredients in TCM have also been extensively studied in the medical field. As a type of TCM against cancer, Rhizoma Paridis (Chinese name: Chonglou) has important antitumor effects in clinical application. The main active ingredients of Rhizoma Paridis (e.g., total saponins, polyphyllin I, polyphyllin II, polyphyllin VI, and polyphyllin VII) have shown strong antitumor activities in various cancers, such as breast cancer, lung cancer, colorectal cancer, hepatocellular carcinoma (HCC), and gastric cancer. Rhizoma Paridis also has low concentrations of certain other active ingredients with antitumor effects, such as saponins polyphyllin E, polyphyllin H, Paris polyphylla-22, gracillin, and formosanin-C. Many researchers have studied the anticancer mechanism of Rhizoma Paridis and its active ingredients. This review article describes research progress regarding the molecular mechanism and antitumor effects of the active ingredients in Rhizoma Paridis, suggesting that various active ingredients in Rhizoma Paridis may be potentially therapeutic against cancer.

The interaction between polyphyllin I and SQLE protein induces hepatotoxicity through SREBP-2/HMGCR/SQLE/LSS pathway.

Polyphyllin I (PPI) and polyphyllin II (PII) are the main active substances in the Paris polyphylla. However, liver toxicity of these compounds has impeded their clinical application and the potential hepatotoxicity mechanisms remain to be elucidated. In this work, we found that PPI and PII exposure could induce significant hepatotoxicity in human liver cell line L-02 and zebrafish in a dose-dependent manner. The results of the proteomic analysis in L-02 cells and transcriptome in zebrafish indicated that the hepatotoxicity of PPI and PII was associated with the cholesterol biosynthetic pathway disorders, which were alleviated by the cholesterol biosynthesis inhibitor lovastatin. Additionally, 3-hydroxy-3-methy-lglutaryl CoA reductase (HMGCR) and squalene epoxidase (SQLE), the two rate-limiting enzymes in the cholesterol synthesis, selected as the potential targets, were confirmed by the molecular docking, the overexpression, and knockdown of HMGCR or SQLE with siRNA. Finally, the pull-down and surface plasmon resonance technology revealed that PPI could directly bind with SQLE but not with HMGCR. Collectively, these data demonstrated that PPI-induced hepatotoxicity resulted from the direct binding with SQLE protein and impaired the sterol-regulatory element binding protein 2/HMGCR/SQLE/lanosterol synthase pathways, thus disturbing the cholesterol biosynthesis pathway. The findings of this research can contribute to a better understanding of the key role of SQLE as a potential target in drug-induced hepatotoxicity and provide a therapeutic strategy for the prevention of drug toxic effects with similar structures in the future.

Development, characterisation, and in vitro anti-tumor effect of self-microemulsifying drug delivery system containing polyphyllin I.

Polyphyllin I (PPI), an effective active ingredient in Paris polyphylla, has a diverse set of pharmacological properties. However, due to its poor solubility and oral absorption, its application and development are limited. In the study, we were committed to improving the solubility of PPI by developing a self-microemulsifying drug delivery system of PPI (PPI-SMEDDS), screening the best preparation process, and evaluating the quality and the in vivo pharmacokinetics of PPI, and PPI-SMEDDS following oral administration to rats were also studied. In addition, the pharmacological activities against human lung adenocarcinoma cell A549 in vitro were assessed. The best formulation had 15.89% ethyl oleate, 47.38% Cremophor RH40, and 36.73% 1,2 propylene glycol. The produced PPI-SMEDDS was clear and transparent, with an average particle size of 24.51 nm and a zeta potential of -17.54 ± 0.51 mV. In vitro, the cumulative release rate of PPI-SMEDDS was nearly 80% within 2 h. PPI-SMEDDS had a substantially greater area under the curve than PPI following oral treatment in rats, and the relative bioavailability of PPI in rats was 278.99%. More importantly, the anti-tumor effect of PPI-SMEDDS in vitro was significantly greater than that of PPI. These findings suggested that PPI-SMEDDS has the potential to improve the solubility, oral bioavailability of PPI, and anti-tumor effect, laying the groundwork for future research on the new PPI dosage form.