Polyphyllin I and VII potentiate the chemosensitivity of A549/DDP cells to cisplatin by enhancing apoptosis, reversing EMT and suppressing the CIP2A/AKT/mTOR signaling axis

Polyphyllin VII Enhances the Antitumor Activity of Cisplatin in Non-Small Cell Lung Cancer Cells by Inducing Ferroptosis and Enhancing Apoptosis

Cisplatin (DDP) resistance in non-small cell lung cancer (NSCLC) is a common cause of treatment failure and a significant contributor to increased mortality. To tackle this issue, the integration of traditional Chinese medicine with chemotherapy has been proposed as a promising approach. The potential synergistic effect of combining polyphyllin VII (PPVII) and DDP in overcoming DDP resistance in NSCLC cells has not been thoroughly investigated yet. In this study, H1299 cells were exposed to gradient concentrations of PPVII and DDP to determine their 50% inhibitory concentration values, and the most effective concentration was applied in subsequent experiments. The combination of PPVII and DDP was evaluated for its effects on H1299 cell proliferation, apoptosis, viability, and the expression of proteins linked to apoptosis and ferroptosis. To further elucidate the underlying mechanisms, the impact of the combination on DNA damage in H1299 cells was also examined. Our results demonstrated that PPVII significantly potentiated the antitumor effects of DDP in H1299 cells in a dose-dependent manner (p < 0.05). Furthermore, PPVII was observed to work synergistically with DDP to suppress proliferation and promote apoptosis in H1299 cells (p < 0.05). Western blotting analysis proved that the combination treatment upregulated proapoptotic proteins (B-cell lymphoma 2-associated X protein, cleaved-caspase 3 and cleaved-PARP), downregulated antiapoptotic protein (Bcl-2), and promoted ferroptosis-associated proteins (long-chain acyl-coenzyme A synthase 4 and NADPH oxidase 4) as well as DNA damage-associated protein (γH2AX) (p < 0.05). Overall, the combination of PPVII and DDP significantly enhanced antitumor activity in H1299 cells through the modulation of DNA damage and ferroptosis, suggesting its potential as an effective therapeutic approach against DDP-resistant NSCLC.

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.

Integrating Chinese medicine into mainstream cancer therapies: a promising future

Malignant tumors are complex systemic chronic diseases and one of the major causes of human mortality. Targeted therapy, chemotherapy, immunotherapy, and radiotherapy are examples of mainstream allopathic medicine treatments that effective for intermediate and advanced malignant tumors. The ongoing use of conventional allopathic medicine has resulted in adverse responses and drug resistance, which have hampered its efficacy. As an important component of complementary and alternative medicine, Chinese medicine has been found to have antitumor effects and has played an important role in enhancing the therapeutic sensitivity of mainstream allopathic medicine, reducing the incidence of adverse events and improving immune-related functions. The combined application of adjuvant Chinese medicine and mainstream allopathic medicine has begun to gain acceptance and is gradually used in the field of antitumor therapy. Traditional natural medicines and their active ingredients, as well as Chinese patent medicines, have been proven to have excellent therapeutic efficacy and good safety in the treatment of various malignant tumors. This paper focuses on the mechanism of action and research progress of combining the above drugs with mainstream allopathic medicine to increase therapeutic sensitivity, alleviate drug resistance, reduce adverse reactions, and improve the body's immune function. To encourage the clinical development and use of Chinese herb adjuvant therapy as well as to provide ideas and information for creating safer and more effective anticancer medication combinations, the significant functions of Chinese herb therapies as adjuvant therapies for cancer treatment are described in detail.

CIP2A interacts with AKT1 to promote the malignant biological behaviors of oral squamous cell carcinoma by upregulating the GSK‑3β/β‑catenin pathway

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies worldwide, which is associated with a poor prognosis. The present study aimed to investigate the role of cancerous inhibitor of protein phosphatase 2A (CIP2A) in OSCC and its regulatory effect on AKT1. Firstly, CIP2A and AKT1 expression in OSCC cells was detected by western blotting. After silencing CIP2A, cell viability and cell proliferation were assessed using the Cell Counting Kit-8 assay and 5-ethynyl-2'-deoxyuridine staining. Cell apoptosis was evaluated by TUNEL staining and the expression of apoptosis-related proteins was assessed using western blotting. Wound healing, Transwell and tube formation assays were performed to evaluate CAL-27 cell migration, invasion and human umbilical vein endothelial cell (HUVEC) tube formation. The interaction between CIP2A and AKT1 was identified by co-immunoprecipitation (co-IP). In addition, AKT1 was overexpressed in CIP2A-silenced CAL-27 cells to perform rescue experiments to analyze the malignant biological functions of CAL-27 cells. Finally, the expression of proteins in the glycogen synthase kinase (GSK)-3β/β-catenin pathway was determined by western blot analysis. Markedly elevated CIP2A and AKT1 expression was observed in OSCC cells. CIP2A knockdown inhibited the viability, proliferation, migration and invasion, and promoted the apoptosis of CAL-27 cells. Concurrently, CIP2A loss-of-function attenuated tube formation. Results of Co-IP confirmed there was an interaction between CIP2A and AKT1. Rescue experiments suggested that AKT1 overexpression alleviated the inhibitory effects of CIP2A knockdown on the viability, proliferation, migration and invasion of CAL-27 cells, as well as tube formation in HUVECs . Additionally, CIP2A silencing significantly downregulated phosphorylated-GSK-3β and β-catenin expression, which was reversed by AKT1 overexpression. In conclusion, CIP2A could interact with AKT1 to promote the malignant biological behaviors of OSCC cells by upregulating the GSK-3β/β-catenin pathway. These findings may provide a targeted therapy for OSCC treatment.

Polyphyllin VII induces CTC anoikis to inhibit lung cancer metastasis through EGFR pathway regulation

Circulating tumor cells (CTCs) are cells that detach from the primary tumor and enter the bloodstream, playing a crucial role in the metastasis of lung cancer. Unfortunately, there is currently a lack of drugs specifically designed to target CTCs and prevent tumor metastasis. In this study, we present evidence that polyphyllin VII, a potent anticancer compound, effectively inhibits the metastasis of lung cancer by inducing a process called anoikis in CTCs. We observed that polyphyllin VII had significant cytotoxicity and inhibited colony formation, migration, and invasion in both our newly established cell line CTC-TJH-01 and a commercial lung cancer cell line H1975. Furthermore, we found that polyphyllin VII induced anoikis and downregulated the TrkB and EGFR-MEK/ERK signaling pathways. Moreover, activation of TrkB protein did not reverse the inhibitory effect of polyphyllin VII on CTCs, while upregulation of EGFR protein effectively reversed it. Furthermore, our immunodeficient mouse models recapitulated that polyphyllin VII inhibited lung metastasis, which was associated with downregulation of the EGFR protein, and reduced the number of CTCs disseminated into the lungs by inducing anoikis. Together, these results suggest that polyphyllin VII may be a promising compound for the treatment of lung cancer metastasis by targeting CTCs.

From Basic Science to Clinical Practice: The Role of Cancerous Inhibitor of Protein Phosphatase 2A (CIP2A)/p90 in Cancer

Cancerous inhibitor of protein phosphatase 2A (CIP2A), initially reported as a tumor-associated antigen (known as p90), is highly expressed in most solid and hematological tumors. The interaction of CIP2A/p90, protein phosphatase 2A (PP2A), and c-Myc can hinder the function of PP2A toward c-Myc S62 induction, thus stabilizing c-Myc protein, which represents a potential role of CIP2A/p90 in tumorigeneses such as cell proliferation, invasion, and migration, as well as cancer drug resistance. The signaling pathways and regulation networks of CIP2A/p90 are complex and not yet fully understood. Many previous studies have also demonstrated that CIP2A/p90 can be used as a potential therapeutic cancer target. In addition, the autoantibody against CIP2A/p90 in sera may be used as a promising biomarker in the diagnosis of certain types of cancer. In this Review, we focus on recent advances relating to CIP2A/p90 and their implications for future research.

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.

Anticancer Effect of Polyphyllin I in Suppressing Stem Cell-Like Properties of Hepatocellular Carcinoma via the AKT/GSK-3β/β-Catenin Signaling Pathway

Polyphyllin I (PPI), also called Chong Lou saponin I, is a steroidal saponin isolated from the rhizome of Paris polyphylla. PPI has been demonstrated to have strong anticancer activity. However, its effect on the stemness of liver cancer stem cells (LCSCs) is not completely understood. Herein, we aimed to investigate the effect of PPI on the stem cell-like features of LCSCs and hepatocellular carcinoma (HCC). LCSCs were enriched in a serum-free medium and treated with PPI, sorafenib (Sora), or PPI and Sora. Several endpoints, including spheroid formation and differentiation, cell proliferation, surface markers of LCSCs, PPI binding targets, and stemness-associated protein expression, were evaluated. Immunofluorescence staining, quantitative real-time polymerase chain reaction, siRNA transfection, and coimmunoprecipitation ubiquitination assays were conducted for in-depth mechanistic studies. Evaluation of in vivo antitumor efficacy demonstrated that PPI effectively inhibited the proliferation of liver cancer cells and the self-renewal and differentiation of LCSCs. Flow cytometry indicated that PPI suppressed the expression of the stem cell surface markers EpCAM and CD13. Molecular docking showed a high affinity between PPI and proteins of the Wnt/β-catenin signaling pathway, including AKT, GSK-3β, and β-catenin, with the binding energies of -5.51, -5.32, and -5.40 kcal/mol, respectively, which suggested that PPI might regulate the Wnt/β-catenin signaling pathway to affect the stem cell-like properties of HCC. Further ex vivo experiments implied that PPI activated the AKT/GSK-3β-mediated ubiquitin proteasomal degradation of β-catenin and subsequently attenuated the prooncogenic effect of LCSCs. Finally, the anticancer property of PPI was confirmed in vivo. It was found that PPI inhibited the tumor growth in an HCC cell line xenograft model. Taken together, molecular docking analysis and experimental data highlighted the novel function of PPI in suppressing the stem cell-like characteristics of LCSCs via the AKT/GSK-3β/β-catenin signaling pathway.

Medicinal herbs and bioactive compounds overcome the drug resistance to epidermal growth factor receptor inhibitors in non-small cell lung cancer

Lung cancer is the leading cause of cancer-related mortality worldwide. Non-small cell lung cancer (NSCLC) accounts for ~85% of all lung cancer cases. Patients harboring epidermal growth factor receptor (EGFR) mutations usually develop resistance to treatment with frontline EGFR-tyrosine kinase inhibitors (EGFR-TKIs). The present review summarizes the current findings and delineates the molecular mechanism of action for the therapeutic effects of herbal extracts and phytochemicals in overcoming EGFR-TKI resistance in NSCLC. Novel molecular targets underlying EGFR-TKI resistance in NSCLC are also discussed. This review provides valuable information for the development of herbal bioactive compounds as alternative treatments for EGFR-TKI-resistant NSCLC.

Anti-angiogenesis and anti-metastasis effects of Polyphyllin VII on Hepatocellular carcinoma cells in vitro and in vivo

Background

Polyphyllin VII (PP7), a steroidal saponin from P. polyphylla has been found to exert strong anticancer activity. Little is known about the anti-angiogenesis and anti-metastasis properties of PP7. In this study, the anti-angiogenic and anti-metastatic effects of PP7 on HCC and the molecular mechanisms were evaluated.

Methods

Effect of PP7 on angiogenesis was assessed by tube formation assay and applied a transgenic Tg(fli1:EGFP) zebrafish model. Effects of PP7 on tumor metastasis and invasion were examined in cell migration and invasion assay, zebrafish tumor xenograft models and lung metastasis mouse models. The protein levels were examined by Western blotting.

Results

PP7 significantly decreased the tube formation of human umbilical vein endothelial cells, the number and length of ISVs and SIVs of transgenic zebrafish, and the metastasis and invasion of cancer cells in vitro and in vivo. The anti-angiogenic and anti-metastatic effects of PP7 in HepG2 cells were attributable, at least partially, to downregulated NF-κB/MMP-9/VEGF signaling pathway.

Conclusion

This study demonstrates that PP7 possesses strong anti-angiogenesis and anti-metastasis activities, suggesting that PP7 could be a potential candidate agent for HCC treatment.

Constitutive Cell Proliferation Regulating Inhibitor of Protein Phosphatase 2A (CIP2A) Mediates Drug Resistance to Erlotinib in an EGFR Activating Mutated NSCLC Cell Line

Exploring mechanisms of drug resistance to targeted small molecule drugs is critical for an extended clinical benefit in the treatment of non-small cell lung cancer (NSCLC) patients carrying activating epidermal growth factor receptor (EGFR) mutations. Here, we identified constitutive cell proliferation regulating inhibitor of protein phosphatase 2A (CIP2A) in the HCC4006rErlo0.5 NSCLC cell line adapted to erlotinib as a model of acquired drug resistance. Constitutive CIP2A resulted in a constitutive activation of Akt signaling. The proteasome inhibitor bortezomib was able to reduce CIP2A levels, which resulted in an activation of protein phosphatase 2A and deactivation of Akt. Combination experiments with erlotinib and bortezomib revealed a lack of interaction between the two drugs. However, the effect size of bortezomib was higher in HCC4006rErlo0.5, compared to the erlotinib-sensitive HCC4006 cells, as indicated by an increase in Emax (0.911 (95%CI 0.867-0.954) vs. 0.585 (95%CI 0.568-0.622), respectively) and decrease in EC50 (52.4 µM (95%CI 46.1-58.8 µM) vs. 73.0 µM (95%CI 60.4-111 µM), respectively) in the concentration-effect model, an earlier onset of cell death induction, and a reduced colony surviving fraction (0.38 ± 0.18 vs. 0.95 ± 0.25, respectively, n = 3, p < 0.05). Therefore, modulation of CIP2A with bortezomib could be an interesting approach to overcome drug resistance to erlotinib treatment in NSCLC.

Crosstalk of long non-coding RNAs and EMT: Searching the missing pieces of an incomplete puzzle for lung cancer therapy

BACKGROUND

Lung cancer is considered to be the first place among the cancer-related deaths worldwide and demands novel strategies in the treatment of this life-threatening disorder. The aim of this review is to explore regulation of epithelial-to-mesenchymal transition (EMT) by long non-coding RNAs (lncRNAs) in lung cancer.

INTRODUCTION

LncRNAs can be considered as potential factors for targeting in cancer therapy, since they regulate a bunch of biological processes, e.g. cell proliferation, differentiation and apoptosis. The abnormal expression of lncRNAs occurs in different cancer cells. On the other hand, epithelial-to-mesenchymal transition (EMT) is a critical mechanism participating in migration and metastasis of cancer cells.

METHOD

Different databases including Googlescholar, Pubmed and Sciencedirect were used for collecting articles using keywords such as "LncRNA", "EMT", and "Lung cancer".

RESULT

There are tumor-suppressing lncRNAs that can suppress EMT and metastasis of lung cancer cells. Expression of such lncRNAs undergoes down-regulation in lung cancer progression and restoring their expression is of importance in suppressing lung cancer migration. There are tumor-promoting lncRNAs triggering EMT in lung cancer and enhancing their migration.

CONCLUSION

LncRNAs are potential regulators of EMT in lung cancer, and targeting them, both pharmacologically and genetically, can be of importance in controlling migration of lung cancer cells.

Cordycepin Reverses Cisplatin Resistance in Non-small Cell Lung Cancer by Activating AMPK and Inhibiting AKT Signaling Pathway

Cisplatin (DDP) is the first-line chemotherapeutic agent against lung cancer. However, the therapeutic effect of DDP loses over time due to the acquired drug resistance in non-small cell lung cancer (NSCLC) cells. In recent years, the role of the traditional Chinese medicine (TCM) cordycepin (Cor) in cancer treatment has been attracting attention. However, the effects of Cor on DDP resistance in NSCLC are unclear. In the present study, we aimed to investigate the effects of Cor in combination with DDP on cell proliferation and apoptosis in NSCLC and explore possible underlying mechanisms. The cell proliferation and apoptosis were analyzed in NSCLC parental (A549) and DDP-resistant (A549DDP) cells treated with DDP alone or in combination with Cor both in vitro and in vivo. Different genes and signaling pathways were investigated between DDP-sensitive and DDP-resistant A549 cells by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The perturbations of the MAPK and PI3K-AKT signaling pathways were evaluated by Western blot analysis. Our data showed that Cor markedly enhanced DDP inhibition on cell proliferation and promotion of apoptosis compared to the DDP-alone group in both A549 and A549DDP cells. The synergic actions were associated with activation of AMPK; inhibition of AKT, mTOR, and downstream P709S6K; and S6 phosphorylation in the AKT pathway compared with DDP alone. Collectively, combination of Cor and DDP has a synergistic effect in inhibiting proliferation and promoting apoptosis of NSCLC cells in the presence or absence of DDP resistance. The antitumor activity is associated with activation of AMPK and inhibition of the AKT pathway to enhance DDP inhibition on NSCLC. Our results suggested that Cor in combination with DDP could be an additional therapeutic option for the treatment of DDP-resistant NSCLC.

Natural Products Targeting the Mitochondria in Cancers

There are abundant sources of anticancer drugs in nature that have a broad prospect in anticancer drug discovery. Natural compounds, with biological activities extracted from plants and marine and microbial metabolites, have significant antitumor effects, but their mechanisms are various. In addition to providing energy to cells, mitochondria are involved in processes, such as cell differentiation, cell signaling, and cell apoptosis, and they have the ability to regulate cell growth and cell cycle. Summing up recent data on how natural products regulate mitochondria is valuable for the development of anticancer drugs. This review focuses on natural products that have shown antitumor effects via regulating mitochondria. The search was done in PubMed, Web of Science, and Google Scholar databases, over a 5-year period, between 2015 and 2020, with a keyword search that focused on natural products, natural compounds, phytomedicine, Chinese medicine, antitumor, and mitochondria. Many natural products have been studied to have antitumor effects on different cells and can be further processed into useful drugs to treat cancer. In the process of searching for valuable new drugs, natural products such as terpenoids, flavonoids, saponins, alkaloids, coumarins, and quinones cover the broad space.

Association of the Epithelial-Mesenchymal Transition (EMT) with Cisplatin Resistance

Therapy resistance is a characteristic of cancer cells that significantly reduces the effectiveness of drugs. Despite the popularity of cisplatin (CP) as a chemotherapeutic agent, which is widely used in the treatment of various types of cancer, resistance of cancer cells to CP chemotherapy has been extensively observed. Among various reported mechanism(s), the epithelial-mesenchymal transition (EMT) process can significantly contribute to chemoresistance by converting the motionless epithelial cells into mobile mesenchymal cells and altering cell-cell adhesion as well as the cellular extracellular matrix, leading to invasion of tumor cells. By analyzing the impact of the different molecular pathways such as microRNAs, long non-coding RNAs, nuclear factor-κB (NF-ĸB), phosphoinositide 3-kinase-related protein kinase (PI3K)/Akt, mammalian target rapamycin (mTOR), and Wnt, which play an important role in resistance exhibited to CP therapy, we first give an introduction about the EMT mechanism and its role in drug resistance. We then focus specifically on the molecular pathways involved in drug resistance and the pharmacological strategies that can be used to mitigate this resistance. Overall, we highlight the various targeted signaling pathways that could be considered in future studies to pave the way for the inhibition of EMT-mediated resistance displayed by tumor cells in response to CP exposure.