Bufalin suppresses ovarian cancer cell proliferation via EGFR pathway

Investigation of the effect of thymoquinone and doxorubicin on the EGFR/FOXP3 signaling pathway in OVCAR3 human ovarian adenocarcinoma cells

PURPOSE

To investigate the cytotoxic and apoptotic effects of the combination of doxorubicin (Dox) and thymoquinone (TQ) on ovarian adenocarcinoma cells (OVCAR3) via the EGFR/FOXP3 signaling pathway.

METHODS

We used human OVCAR3 and human skin keratinocyte cells (HaCaT). Different concentrations of TQ and Dox were applied to the cells for 24, 48, and 72 hours, and the cytotoxicity level was determined via the MTT method. Expression levels of EGFR/FOXP3 for cell proliferation and apoptosis were determined by quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blot analysis. The colony counting was performed after DAPI staining, and the effect on cell proliferation was determined.

RESULTS

Cytotoxicity was found to be highest with TQ and Dox treatments, and cell migration was prevented, especially in the group that received combined TQ and Dox treatment. Moreover, using RT-qPCR analysis, activity in the EGFR and FOXP3 pathway was found to be downregulated the most with TQ, and the amount of protein decreased with TQ and Dox.

CONCLUSIONS

The findings showed that the greatest cytotoxic effect and the most apoptosis occurred during TQ treatment. Additionally, it was determined that a significant decrease in EGFR and FOXP3 levels occurred with the application of TQ and Dox.

An inulin-type fructan CP-A from Codonopsis pilosula combined with 5-Fluorouracil alleviates colitis-associated tumorigenesis via inhibition of EGFR/AKT/ERK signaling pathway and regulation of intestinal flora

Inulin-type fructan CP-A, the main component of Codonopsis pilosula polysaccharides, has been found to have therapeutic effects on ulcerative colitis (UC). Herein, we established a colitis-associated cancer (CAC) mouse model by azomethane (AOM) and dextran sulfate sodium (DSS) and selected mouse colon cancer cells CT-26 to explore the therapeutic effects of the combined administration of CP-A and 5-fluorouracil (5-FU) in vivo and in vitro. High-throughput transcriptomics sequencing technology was used to identify differentially expressed genes (DEGs) in the mouse colon and enrich related pathways. 16S rRNA gene sequencing technology was used for gut microbiota research to identify microbial changes in mouse feces. Short-chain fatty acid (SCFA) content was identified in the mouse colon using gas chromatography-mass spectroscopy (GC-MS). In vivo experiments showed that compared with untreated CAC mice, those treated with the combined administration of CP-A and 5-FU had significantly restored body weight, fewer tumors, smaller tumor volume, and reduced disease activity index (DAI) and histopathological scores. The combination of CP-A and 5-FU increased the anti-inflammatory cytokine interleukin 10 (IL-10) and inhibited the expression of pro-inflammatory cytokines interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), and interferon-gamma (IFN-γ). In vitro experiments indicated that a combination of CP-A and 5-FU promoted the apoptosis of CT-26 cells. The results of transcriptomics studies suggested that the therapeutic effect of the combined administration of CP-A and 5-FU on CAC may be related to the EGFR/AKT/ERK pathway. Both in vivo and in vitro experiments verified the regulatory effect of the combined administration of CP-A and 5-FU on the EGFR/AKT/ERK pathway. Moreover, the intestinal flora experiment manifested that compared with untreated CAC mice, the combined CP-A and 5-FU group had a more stable intestinal microbiota composition, and the combined administration of CP-A and 5-FU increased the abundance of SCFAs. Our experimental findings have demonstrated that the combination of CP-A and 5-FU exhibits promising efficacy in the treatment of CAC, warranting further clinical investigation in the future.

Effect of icariin on ovarian cancer: a combined network pharmacology and meta-analysis of in vitro studies approach

Introduction

An abundance of experimental evidence indicates that icariin (ICA) could potentially exert an anti-tumor effect on ovarian cancer (OC). Nevertheless, the reliability of this evidence remains ambiguous. This study aimed to explore the impact of ICA on OC and the underlying mechanisms.

Methods

Bioinformatics analysis was employed to pinpoint ICA-targeted genes and signaling pathways implicated in OC, utilizing network pharmacology. Subsequently, PubMed, EMBASE, and Web of Science databases were systematically searched from 2001 through June 2023 for in vitro trials evaluating the anti-tumor efficacy of conventional ICA versus placebo in OC. The pathways and genes identified in the literature were recorded, and the therapeutic targets were statistically analyzed and compared with the predicted targets from network pharmacology to confirm the precision of the targets.

Results and Discussion

Fourteen target genes were validated with success. The pathways corresponding to the remaining genes-excluding these 14-were analyzed and found to be primarily associated with cell apoptosis, anti-tumor, and other related pathways. Out of the 76 studies retrieved, eight fulfilled the inclusion criteria. The subsequent meta-analysis suggested that ICA treatment was significantly correlated with reduced cell growth and induced apoptosis. This study demonstrated a certain efficacy of ICA compared to placebo in enhancing anti-tumor outcomes, characterized by increased abilities in reducing cell growth and inducing apoptosis. The pathways involved in the therapeutic effect may be linked to cell apoptosis and anti-tumor mechanisms.

Inhibiting FGFR by toadflax reverses erlotinib resistance in nonsmall cell lung cancer

This study aims to demonstrate the effect of toadflax (bufalin) on erlotinib resistance in nonsmall cell lung cancer (NSCLC) by inhibiting the fibroblast growth factor receptor (FGFR). The microfluidic mobility transferase and caliper mobility-shift assays were employed to detect the FGFR inhibition by bufalin and the binding reversibility. Further, the inhibitory effects of bufalin were determined in HCC827 and HCC827/ER cells in vitro, investigating relative FGFR overexpression by quantitative reverse transcriptase-PCR (RT-qPCR) and FGFR downstream proteins, that is, FGFR substrate 2 (FRS2), extracellular signal-regulated kinase (ERK), and S6 by western blot analysis. Finally, HCC827/ER-inoculated xenograft tumors were constructed to observe the effects of bufalin and bufalin + erlotinib intervention on tumor growth. Bufalin inhibited FGFR by reversibly binding to FGFR1. In addition, the western blot analysis indicated a significant reduction in the expression levels of FGFR, FRS2, ERK, and S6 proteins in HCC827 and HCC827/ER cells, increasing the expression levels of apoptotic caspase-3 and poly-(ADP-ribose) polymerase proteins. Bufalin + erlotinib combination significantly inhibited the apoptosis of HCC827/ER cells and subsequent tumor growth in vivo. In addition, FGFR overexpression significantly reversed the sensitivity of bufalin to HCC827/ER cells, promoting the value-addition of HCC827/ER cells. Further, bufalin + erlotinib significantly reduced the growth of erlotinib-resistant HCC827/ER tumors, induced apoptosis, and inhibited the expression of FGFR and p-ERK proteins. These findings indicated that bufalin could reverse the erlotinib resistance in NSCLC by inhibiting the FGFR expression.

Bufalin-Loaded Multifunctional Photothermal Nanoparticles Inhibit the Anaerobic Glycolysis by Targeting SRC-3/HIF-1α Pathway for Improved Mild Photothermal Therapy in CRC

Purpose

Compared with traditional photothermal therapy (PTT, >50°C), mild PTT (≤45°C) is a promising strategy for tumor therapy with fewer adverse effects. Unfortunately, its anti-tumor efficacy is hampered by thermoresistance induced by overexpression of heat shock proteins (HSPs). In our previous study, we found bufalin (BU) is a glycolysis inhibitor that depletes HSPs, which is expected to overcome thermotolerance of tumor cells. In this study, BU-loaded multifunctional nanoparticles (NPs) were developed for enhancing the mild PTT of colorectal cancer (CRC).

Methods

Fe3O4 NPs coated with the polydopamine (PDA) shell modified with polyethylene glycol (PEG) and cyclic arginine-glycyl-aspartic peptide (cRGD) for loading BU (Fe3O4@PDA-PEG-cRGD/BU NPs) were developed. The thermal variations in Fe3O4@PDA-PEG-cRGD/BU NPs solution under different conditions were measured. Glycolysis inhibition was evaluated by measuring the glucose uptake, extracellular lactate, and intracellular adenosine triphosphate (ATP) levels. The cellular cytotoxicity of Fe3O4@PDA-PEG-cRGD/BU NPs was analyzed using a cell counting kit-8 assay, Calcein-AM/PI double staining, and flow cytometry in HCT116 cells. The magnetic resonance imaging (MRI) performance and anti-tumor therapeutic efficacy of Fe3O4@PDA-PEG-cRGD/BU NPs were evaluated in HCT116-tumor bearing mice.

Results

Fe3O4@PDA-PEG-cRGD/BU NPs had an average diameter of 260.4±3.5 nm, the zeta potential of -23.8±1.6 mV, the drug loading rate of 1.1%, which had good thermal stability, photothermal conversion efficiencies and MRI performance. In addition, the released BU not only killed tumor cells but also interfered with glycolysis by targeting the steroid receptor coactivator 3 (SRC-3)/HIF-1α pathway, preventing intracellular ATP synthesis, and combating HSP-dependent tumor thermoresistance, ultimately strengthening the thermal sensitivity toward mild PTT both in vitro and in vivo.

Conclusion

This study provides a highly effective strategy for enhancing the therapeutic effects of mild PTT toward tumors.

A novel TCGA-validated programmed cell-death-related signature of ovarian cancer

BACKGROUND

Ovarian cancer (OC) is a gynecological malignancy tumor with high recurrence and mortality rates. Programmed cell death (PCD) is an essential regulator in cancer metabolism, whose functions are still unknown in OC. Therefore, it is vital to determine the prognostic value and therapy response of PCD-related genes in OC.

METHODS

By mining The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx) and Genecards databases, we constructed a prognostic PCD-related genes model and performed Kaplan-Meier (K-M) analysis and Receiver Operating Characteristic (ROC) curve for its predictive ability. A nomogram was created via Cox regression. We validated our model in train and test sets. Quantitative real-time PCR (qRT-PCR) was applied to identify the expression of our model genes. Finally, we analyzed functional analysis, immune infiltration, genomic mutation, tumor mutational burden (TMB) and drug sensitivity of patients in low- and high-risk group based on median scores.

RESULTS

A ten-PCD-related gene signature including protein phosphatase 1 regulatory subunit 15 A (PPP1R15A), 8-oxoguanine-DNA glycosylase (OGG1), HECT and RLD domain containing E3 ubiquitin protein ligase family member 1 (HERC1), Caspase-2.(CASP2), Caspase activity and apoptosis inhibitor 1(CAAP1), RB transcriptional corepressor 1(RB1), Z-DNA binding protein 1 (ZBP1), CD3-epsilon (CD3E), Clathrin heavy chain like 1(CLTCL1), and CCAAT/enhancer-binding protein beta (CEBPB) was constructed. Risk score performed well with good area under curve (AUC) (AUC3 - year =0.728, AUC5 - year = 0.730). The nomogram based on risk score has good performance in predicting the prognosis of OC patients (AUC1 - year =0.781, AUC3 - year =0.759, AUC5 - year = 0.670). Kyoto encyclopedia of genes and genomes (KEGG) analysis showed that the erythroblastic leukemia viral oncogene homolog (ERBB) signaling pathway and focal adhesion were enriched in the high-risk group. Meanwhile, patients with high-risk scores had worse OS. In addition, patients with low-risk scores had higher immune-infiltrating cells and enhanced expression of checkpoints, programmed cell death 1 ligand 1 (PD-L1), indoleamine 2,3-dioxygenase 1 (IDO-1) and lymphocyte activation gene-3 (LAG3), and were more sensitive to A.443,654, GDC.0449, paclitaxel, gefitinib and cisplatin. Finally, qRT-PCR confirmed RB1, CAAP1, ZBP1, CEBPB and CLTCL1 over-expressed, while PPP1R15A, OGG1, CASP2, CD3E and HERC1 under-expressed in OC cell lines.

CONCLUSION

Our model could precisely predict the prognosis, immune status and drug sensitivity of OC patients.

Sensational site: the sodium pump ouabain-binding site and its ligands

Cardiotonic steroids (CTS), used by certain insects, toads, and rats for protection from predators, became, thanks to Withering's trailblazing 1785 monograph, the mainstay of heart failure (HF) therapy. In the 1950s and 1960s, we learned that the CTS receptor was part of the sodium pump (NKA) and that the Na+/Ca2+ exchanger was critical for the acute cardiotonic effect of digoxin- and ouabain-related CTS. This "settled" view was upended by seven revolutionary observations. First, subnanomolar ouabain sometimes stimulates NKA while higher concentrations are invariably inhibitory. Second, endogenous ouabain (EO) was discovered in the human circulation. Third, in the DIG clinical trial, digoxin only marginally improved outcomes in patients with HF. Fourth, cloning of NKA in 1985 revealed multiple NKA α and β subunit isoforms that, in the rodent, differ in their sensitivities to CTS. Fifth, the NKA is a cation pump and a hormone receptor/signal transducer. EO binding to NKA activates, in a ligand- and cell-specific manner, several protein kinase and Ca2+-dependent signaling cascades that have widespread physiological effects and can contribute to hypertension and HF pathogenesis. Sixth, all CTS are not equivalent, e.g., ouabain induces hypertension in rodents while digoxin is antihypertensinogenic ("biased signaling"). Seventh, most common rodent hypertension models require a highly ouabain-sensitive α2 NKA and the elevated blood pressure is alleviated by EO immunoneutralization. These numerous phenomena are enabled by NKA's intricate structure. We have just begun to understand the endocrine role of the endogenous ligands and the broad impact of the ouabain-binding site on physiology and pathophysiology.

Application of SNAP-tag-EGFR cell membrane chromatography model in screening antitumor active components of Silybum marianum (L.) Gaertn

The SNAP-tag-epidermal growth factor receptor (SNAP-tag-EGFR) cell membrane chromatography (CMC) model is a powerful tool for investigating ligand-receptor interactions and screening active ingredients in traditional Chinese medicine. Most tyrosine kinase inhibitors (TKIs) target epidermal growth factor receptors. However, TKIs associated with significant side effects and drug resistance must be addressed immediately. Therefore, there is an urgent need to develop new TKIs with high efficiency and low toxicity. Because of its low toxicity and side effects, traditional Chinese medicine has been widely employed to treat various diseases, including cancer. Hence, this study aimed to use the SNAP-tag-EGFR/CMC-high-performance liquid chromatography-mass spectrometry (HPLC-MS) two-dimensional system model as the research tool to screen and identify potential EGFR antagonists from the Chinese medicine Silybum marianum (L.) Gaertn. The applicability of the system was verified using the positive control drug osimertinib. Four potential EGFR antagonists were screened from the Chinese medicine Silybum marianum (L.) Gaertn.. They were identified as silydianin, silychristin, silybin, and isosilybin. Additionally, their pharmacological activity was preliminarily verified using a CCK-8 assay. The kinetic parameters of the four active ingredients interacting with EGFR and their binding modes with EGFR were analyzed using nonlinear chromatography (NLC) and molecular docking. This study identified silydianin, silychristin, silybin, and isosilybin from Silybum marianum (L.) Gaertn. and verified their potential antitumor effects on EGFR.

Comparison of the Ways in Which Nitidine Chloride and Bufalin Induce Programmed Cell Death in Hematological Tumor Cells

The objective of this work to study the programmed cell death (PCD) in hematological tumor cells induced by nitidine chloride (NC) and bufalin (BF). Hematological tumor cells were exposed to various doses of NC and BF to measure the level of growth inhibition. While inverted microscope is used to observe cell morphology, western blot technique is used to detect apoptosis-related protein expression levels. The effects of NC and BF on hematological tumor cells were different. Although abnormal cell morphology could be seen under the inverted microscope, the western blot results showed that the two medicines induced PCD through different pathways. Drug resistance varied in intensity across distinct cells. THP-1, Jurkat, and RPMI-8226 each had half maximum inhibitory concentrations (IC50) of 36.23 nM, 26.71 nM, and 40.46 nM in BF, and 9.24 µM, 4.33 µM, and 28.18 µM in NC, respectively. Different hematopoietic malignancy cells exhibit varying degrees of drug resistance, and the mechanisms by which apoptosis of hematologic tumor cells is triggered by NC and BF are also distinct.

Bufalin targeting BFAR inhibits the occurrence and metastasis of gastric cancer through PI3K/AKT/mTOR signal pathway

Gastric cancer (GC) is the most common malignant tumor of digestive system. Bufalin extracted from Venenum Bufonis is one of the most effective anticancer monomers, which has been proved to play anticancer roles in a variety of cancers such as ovarian cancer, prostate cancer and neuroblastoma. However, there are few studies on bufalin in GC, and lack of clear targets. The effect of bufalin on the proliferation and migration of GC cells was detected by CCK-8, scratch wound healing assay, transwell assay and Western blotting. The potential direct interaction proteins of bufalin were screened by human proteome microarray containing 21,838 human proteins. The target protein was determined by bioinformatics, and the binding sites were predicted by molecular docking technique. Biological experiments in vitro and in vivo were conducted to verify the effect of bufalin directly interaction protein and the mechanism of bufalin targeting the protein to inhibit the development of GC. The results showed that bufalin inhibited the proliferation and migration of MKN-45 and HGC-27 GC cell lines in vitro. BFAR, a direct interaction protein of bufalin has several potential binding sites to bufalin. BFAR is highly expressed in GC and promotes the occurrence and metastasis of GC by activating PI3K/AKT/mTOR signal pathway in vitro and in vivo. Bufalin reversed the promoting effect of BFAR on the carcinogenesis and metastasis of GC by down-regulating the expression of BFAR. Our results show that bufalin targeting BFAR inhibits the occurrence and metastasis of GC through PI3K/AKT/mTOR signal pathway. These results provide a new basis for bufalin as a promising drug for the treatment of GC.

Toad venom bufadienolides and bufotoxins: An updated review

Bufadienolides, naturally found in toad venoms having steroid-like structures, reveal antiproliferative effects at low doses. However, their application as anticancer drugs is strongly prevented by their Na+ /K+ -ATPase binding activities. Although several kinds of research were dedicated to moderating their Na+ /K+ -ATPase binding activity, still deeper fundamental knowledge is required to bring these findings into medical practice. In this work, we reviewed data related to anticancer activity of bufadienolides such as bufalin, arenobufagin, bufotalin, gamabufotalin, cinobufotalin, and cinobufagin and their derivatives. Bufotoxins, derivatives of bufadienolides containing polar molecules mainly belonging to argininyl residues, are reviewed as well. The established structures of bufotoxins have been compiled into a one-page figure to review their structures. We also highlighted advances in the structure-modification of the structure of compounds in this class. Drug delivery approaches to target these compounds to tumor cells were discussed in one section. The issues related to extraction, identification, and quantification are separated into another section.

Bufalin reverses ABCB1-mediated resistance to docetaxel in breast cancer

Background

Docetaxel (DCT) is widely used in clinical practice, but the drug resistance of breast cancer patients has become an important reason to limit its clinical efficacy. Chan'su is a commonly used traditional Chinese medicine for the treatment of breast cancer. Bufalin (BUF) is a bioactive polyhydroxy steroid extracted from chan'su and has strong antitumor activity, but there are few studies on reversing drug resistance in breast cancer. The aim of this study is to determine whether BUF can reverse the drug resistance to DCT and restore efficacy in breast cancer.

Methodology

The reversal index of BUF was detected by Cell Counting Kit-8 (CCK-8) assays. The effects of BUF on enhancing the apoptosis of DCT were detected by flow cytometry and Western Blot (WB), and the main differential expression levels of sensitive and resistant strains were detected by high-throughput sequencing. Rhodamine 123 assay, WB and ATP Binding Cassette Subfamily B Member 1 (ABCB1) ATPase activity experiments were used to detect the effect of BUF on ABCB1. The nude mouse orthotopic model was constructed to investigate the reversal effect of BUF on DCT resistance in vivo.

Results

With BUF intervention, the sensitivity of drug-resistant cell lines to DCT was increased. BUF can inhibit the expression of ABCB1 protein, increase the drug accumulation of DCT in drug-resistant strains, and reduce the ATPase activity of ABCB1. Animal experiments show that BUF can inhibit the growth of drug-resistant tumors in an orthotopic model of breast cancer and decrease the expression of ABCB1.

Conclusion

BUF can reverse ABCB1-mediated docetaxel resistance in breast cancer.