Combinational Antitumor Strategies Based on the Active Ingredients of Toad Skin and Toad Venom.

A multidrug combination strategy is an important mean to improve the treatment of cancer and is the mainstream scheme of clinical cancer treatment. The active ingredients of traditional Chinese medicine, represented by toad skin and toad venom, have the advantages of high efficiency, low toxicity, wide action and multiple targets and have become ideal targets in combined treatment strategies for tumors in recent years. Toad skin and toad venom are traditional Chinese animal medicines derived from Bufo bufo gargarizans Cantor or Bufo melanostictus Schneider that have shown excellent therapeutic effects on the treatment of various cancers and cancer pain as adjuvant antitumor drugs in clinical practice. The involved mechanisms include inducing apoptosis, arresting the cell cycle, inhibiting cell proliferation, migration and invasion, inhibiting tumor angiogenesis, reversing the multidrug resistance of tumor cells, and regulating multiple signaling pathways and targets. Moreover, a multidrug combination strategy based on a nanodelivery system can realize the precise loading of the active ingredients of toad skin or toad venom and other antitumor drugs and carry drugs to overcome physiological and pathological barriers, complete efficient enrichment in tumor tissues, and achieve targeted delivery to tumor cells and the controlled release of drugs, thus enhancing antitumor efficacy and reducing toxicity and side effects. This article reviewed the clinical efficacy and safety of the combination of toad skin and toad venom with chemotherapeutic drugs, targeted drugs, analgesics and other drugs; evaluated the effects and mechanisms of the combination of toad skin and toad venom with chemotherapy, targeted therapy, radiotherapy or hyperthermia, traditional Chinese medicine, signaling pathway inhibitors and other therapies in cell and animal models; and summarized the codelivery strategies for the active ingredients of toad skin and toad venom with chemotherapeutic drugs, small-molecule targeted drugs, monoclonal antibodies, active ingredients of traditional Chinese medicine, and photodynamic and photothermal therapeutic drugs to provide a basis for the rational drug use of toad skin and toad venom in the clinic and the development of novel drug delivery systems.

Advances on Delivery System of Active Ingredients of Dried Toad Skin and Toad Venom.

Dried toad skin (TS) and toad venom (TV) are the dried skin of the Bufo bufo gargarizans Cantor and the Bufo melanostictus Schneider, which remove the internal organs and the white secretions of the skin and retroauricular glands. Since 2005, cinobufacini preparations have been approved by the State Food and Drug Administration for use as adjuvant therapies in the treatment of various advanced cancers. Meanwhile, bufalenolides has been identified as the main component of TS/TV, exhibiting antitumor activity, inducing apoptosis of cancer cells and inhibiting cancer cell proliferation or metastasis through a variety of signaling pathways. However, clinical agents frequently face limitations such as inherent toxicity at high concentrations and insufficient tumor targeting. Additionally, the development and utilization of these active ingredients are hindered by poor water solubility, low bioavailability, and rapid clearance from the bloodstream. To address these challenges, the design of a targeted drug delivery system (TDDS) aims to enhance drug bioavailability, improve targeting within the body, increase drug efficacy, and reduce adverse reactions. This article reviews the TDDS for TS/TV, and their active components, including passive, active, and stimuli-responsive TDDS, to provide a reference for advancing their clinical development and use.

Tilianin enhances the antitumor effect of sufentanil on non-small cell lung cancer.

Non-small cell cancer (NSCLC) is the most common cancer in the world, but its effective therapeutic methods are limited. Tilianin and sufentanil alleviate various human tumors. This research aimed to clarify the functions and mechanisms of Tilianin and sufentanil in NSCLC. The functions of Tilianin and sufentanil on NSCLC cell viability, apoptosis, mitochondrial dysfunction, and immunity in vitro were examined using Cell Counting Kit-8 assay, flow cytometry, reactive oxygen species level analysis, CD8+ T cell percentage analysis, Western blot, and enzyme-linked immunosorbent assay, respectively. The molecular mechanism regulated by Tilianin and sufentanil in NSCLC was assessed using Western blot, and immunofluorescence assays. Meanwhile, the roles of Tilianin and sufentanil in NSCLC tumor growth, apoptosis, and immunity in vivo were determined by establishing a tumor xenograft mouse model, immunohistochemistry, and Western blot assays. When sufentanil concentration was proximity 2 nM, the inhibition rate of NSCLC cell viability was 50%. The IC50 for A549 cells was 2.36 nM, and the IC50 for H1299 cells was 2.18 nM. The IC50 of Tilianin for A549 cells was 38.7 µM, and the IC50 of Tilianin for H1299 cells was 44.6 µM. Functionally, 0.5 nM sufentanil and 10 µM Tilianin reduced NSCLC cell (A549 and H1299) viability in a dose-dependent manner. Also, 0.5 nM sufentanil and 10 µM Tilianin enhanced NSCLC cell apoptosis, yet this impact was strengthened after a combination of Tilianin and Sufentanil. Furthermore, 0.5 nM sufentanil and 10 µM Tilianin repressed NSCLC cell mitochondrial dysfunction and immunity, and these impacts were enhanced after a combination of Tilianin and Sufentanil. Mechanistically, 0.5 nM sufentanil and 10 µM Tilianin repressed the NF-κB pathway in NSCLC cells, while this repression was strengthened after a combination of Tilianin and Sufentanil. In vivo experimental data further clarified that 1 µg/kg sufentanil and 10 mg/kg Tilianin reduced NSCLC growth, immunity, and NF-κB pathway-related protein levels, yet these trends were enhanced after a combination of Tilianin and Sufentanil. Tilianin strengthened the antitumor effect of sufentanil in NSCLC.

Comparative study on pharmacokinetics of extract from Bufonis venenum and its liposomes.

Bufadienolides and indolealkylamines, the primary active components in Bufonis venenum, have rapid clearance from the body with a short half-life, leading to low bioavailability. Moreover, Bufadienolides and indolealkylamines are associated with serious adverse effects. In order to reduce the toxicities, minimize the adverse effects and simultaneously load lipophilic bufadienolides and hydrophilic indolealkylamines with satisfactory drug loading and encapsulation rate, we prepared Bufonis venenum extract-liposomes (BVE-LP). To compare the pharmacokinetic differences between Bufonis venenum extract (BVE) and its liposomes, ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) assay was established to simultaneously detect the 12 chemical components in rat plasma. Results of pharmacokinetic study in SD rats showed that the highest exposure based on the area under the plasma concentration-time curve (AUC0-t) was obtained by 5-hydroxytryptamine with a mean value of 267.097 µg/L*h in BVE-LP group, which was 72.36 % higher as compared to that obtained in Bufonis venenum extract (BVE) group with a mean value of AUC0-t of 154.966 µg/L*h. The exposure (AUC0-t) of desacetylcinobufotalin, desacetylcinobufagin, arenobufagin and telocinobufagin in BVE-LP group was 111.89 %, 94.13 %, 134.08 %, and 92.94 % higher when compared to that in BVE group. With the employment of liposomes, there was an obvious decrease in the clearance of bufotenidine, desacetylcinobufotalin, gamabufotalin, arenobufagin, and telocinobufagin. The terminal half life (t1/2) of desacetylcinobufotalin, gamabufotalin, arenobufagin, and telocinobufagin in BVE-LP group was increased by 185.96 %, 292.64 %, 196.78 % and 131.29 % when compared to that in BVE group. All the results above indicated that a slower elimination rate and more exposure of some bufadienolides and indolealkylamines was obtained by BVE-LP when compared to BVE group, which verified BVE-LP could provide a therapeutic option for effective delivery of Bufonis venenum in clinical. DATA AVAILABILITY: The data will be shared on reasonable request to the corresponding author.

Isolation, Identification and Chemical Modification of Bufadienolides from Bufo melanostictus Schneider and Their Cytotoxic Activities against Prostate Cancer Cells.

The traditional Chinese medicine toad venom (Venenum bufonis) has been extensively used to treat various diseases, including cancers, in China and other Southeast Asian countries. The major constituents of toad venom, e.g., bufadienolides and alkaloids, exhibit broad-spectrum pharmacological effects in cancers. Herein, two new bufadienolides (1 and 2), along with eleven known compounds (3-13) were successfully isolated from Bufo melanostictus Schneider. Their structures were elucidated by extensive spectroscopic data and X-ray diffraction analysis. Furthermore, four lactam derivatives were synthesized through the transformation of bufadienolides lactones. The inhibitory effects of these compounds against human prostate cancer cell lines PC-3 and DU145 were evaluated. The outcomes indicated a notable trend, with a substantial subset displaying nanomolar range IC50 values against PC-3 and DU145 cells, underscoring their pronounced cytotoxicity. Moreover, a noteworthy distinction surfaces, wherein lactones consistently outperformed their lactam counterparts, further validating their heightened potency for the treatment of prostate cancer. This study contributes significant preclinical evidence substantiating the therapeutic viability of bufadienolides and toad venom as intervention strategies for prostate cancer.

Arenobufagin enhances T-cell anti-tumor immunity in colorectal cancer by modulating HSP90ß accessibility.

BACKGROUND: Colorectal cancer (CRC) is a significant public health issue, ranking as one of the predominant cancer types globally in terms of incidence. Intriguingly, Arenobufagin (Are), a compound extracted from toad venom, has demonstrated the potential to inhibit tumor growth effectively. PURPOSE: This study aimed to explore Are's molecular targets and unravel its antitumor mechanism in CRC. Specifically, we were interested in its impact on immune checkpoint modulation and correlations with HSP90ß-STAT3-PD-L1 axis activity. METHODS: We investigated the in vivo antitumor effects of Are by constructing a colorectalcancer subcutaneous xenograft mouse model. Subsequently, we employed single-cell multi-omics technology to study the potential mechanism by which Are inhibits CRC. Utilizing target-responsive accessibility profiling (TRAP) technology, we identified heatshock protein 90ß (HSP90ß) as the direct target of Are, and confirmed this through a microscale thermophoresis experiment (MST). Further downstream mechanisms were explored through techniques such as co-immunoprecipitation, Western blotting, qPCR, and immunofluorescence. Concurrently, we arrived at the same research conclusion at the organoid level by co-cultivating with immune cells. RESULTS: We observed that Are inhibits PD-Ll expression in CRC tumor xenografts at low concentrations. Moreover, TRAP revealed that HSP90ß's accessibility significantly decreased upon Are binding. We demonstrated a decrease in the activity of the HSP90ß-STAT3-PD-Ll axis following low-concentration Are treatment in vivo. The PDO analysis showed improved enrichment of lymphocytes, particularly T cells, on the PDOs following Are treatment. CONCLUSION: Contrary to previous research focusing on the direct cytotoxicity of Are towards tumor cells, our findings indicate that it can also inhibit tumor growth at lower concentrations through the modulation of immune checkpoints. This study unveils a novel anti-tumor mechanism of Are and stimulates contemplation on the dose-response relationship of natural products, which is beneficial for the clinical translational application of Are.

Arenobufagin modulation of PCSK9-mediated cholesterol metabolism induces tumor-associated macrophages polarisation to inhibit hepatocellular carcinoma progression.

BACKGROUND: The tumor microenvironment (TME) of hepatocellular carcinoma is heterogeneous enough to be prone to drug resistance and multidrug resistance during treatment, and reprogramming of cholesterol metabolism in TME mediates tumor-associated macrophages (TAMs) polarization, which has an impact on the regulation of malignant tumor progression. Arenobufagin (ARBU) was extracted and isolated from toad venom (purity ≥98 %), which is the main active ingredient of the traditional Chinese medicine Chan'su with good anti-tumor effects. PURPOSE: To investigate the regulatory effect of ARBU on lipid metabolism in tumor microenvironment, interfere with macrophage polarization, and determine its mechanism of action on liver cancer progression. METHODS: In this study, the inhibitory effect of ARBU on the proliferation of Hepa1-6 in C57 mice and the safety of administration were evaluated by establishing a transplanted tumor model of Hepa1-6 hepatocellular carcinoma mice and using 5-FU as a positive control drug. In addition, we constructed a co-culture system of Hepa1-6 cells and primary mouse macrophages to study the effects of ARBU on the polarization phenotypic transformation of macrophages and the proliferation and migration of hepatoma cells. The influence of ARBU on the metabolism of lipids in the hepatocellular carcinoma mouse model was investigated by combining it with lipidomics technology. The influence of ARBU on the PCSK9/LDL-R signaling pathway and macrophage polarization, which regulate cholesterol metabolism, was tested by using qRT-PCR, gene editing, IF, and WB. CONCLUSION: ARBU significantly inhibited the proliferation of Hepa1-6 in vivo and in vitro, regulated cholesterol metabolism, and promoted the M1-type polarization of macrophages in the tumor microenvironment. ARBU inhibits cholesterol synthesis in the TME through the PCSK9/LDL-R signaling pathway, thereby blocking macrophage M2 polarization, promoting apoptosis of the tumor cells, and inhibiting their proliferation and migration.

Efficacy and Safety of Huachansu as an Adjuvant Therapy for Non-Small Cell Lung Cancer: An Overview of Systematic Reviews and Meta-Analyses.

OBJECTIVE: The purpose of this overview is to assess systematic reviews (SRs)/ meta-analyses (MAs) of Huachansu (HCS) combination chemotherapy for treating non-small cell lung cancer (NSCLC) and provide summarized evidence for clinical decision making. METHODS: From the creation of the database to JUNE 2023, 8 databases in English and Chinese were searched. SRs/MAs that met the inclusion and exclusion criteria were included. Two reviewers independently screened research, extracted data and assessed methodological quality, risk of bias, report quality and evidence quality by using relevant criteria from AMSTAR-2, ROBIS scale, PRISMA, and GRADE system. RESULTS: The short-term effect, long-term effect, quality of life improvement, safety and pain relief effect in 8 included SRs/MAs were assessed in this overview according to quantitative synthesis. Results assessed by AMSTAR-2, PRISMA, and ROBIS were generally unsatisfactory, with the results of the AMSTAR-2 assessment showing that all of them were of low or critically low quality; the number of items in the included research that were fully reported (compliance was 100%) by the PRISMA checklist was only 50%, while there were 38.10% of the research reporting less than 60% completeness; the ROBIS assessment showed a small number of systems to be low risk of bias. In addition, 26 items were rated as moderate quality, while 50.94% of items were rated as low or critically low quality by GRADE. CONCLUSION: HCS may be a promising adjuvant therapy for NSCLC. However, high-quality SRs/MAs and randomized control trials (RCTs) should be conducted to provide sufficient evidence so as to draw a definitive conclusion.

Divergent Nine-Step Syntheses of Perhydrohistrionicotoxin Analogs and Their Inhibition Activity Toward Chicken α4ß2-Neuronal Nicotinic Acetylcholine Receptors.

Histrionicotoxin (HTX) alkaloids, which are isolated from Colombian poison dart frogs, are analgesic neurotoxins that modulate nicotinic acetylcholine receptors (nAChRs) as antagonists. Perhydrohistrionicotoxin (pHTX) is the potent synthetic analogue of HTX and possesses a 1-azaspiro[5.5]undecane skeleton common to the HTX family. Here, we show for the first time the divergent nine-step synthesis of pHTX and its three stereoisomers from the known aldehyde through a one-step construction of the 1-azaspiro[5.5]undecane framework from a linear amino ynone substrate. Surprisingly, some pHTX diastereomers exhibited antagonistic activities on the chicken α4ß2-neuronal nAChRs that were more potent than pHTX.

Modulating pancreatic cancer microenvironment: The efficacy of Huachansu in mouse models via TGF-ß/Smad pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Huachansu (HCS) is a traditional Chinese medicine obtained from the dried skin glands of Bufo gargarizans and clinical uses of HCS have been approved in China to treat malignant tumors. The traditional Chinese medicine theory states that HCS relieves patients with cancer by promoting blood circulation to remove blood stasis. Clinical observation found that local injection of HCS given to pancreatic cancer patients can significantly inhibit tumor progression and assist in enhancing the efficacy of chemotherapy. However, the material basis and underlying mechanism have not yet been elucidated. AIM OF THE STUDY: To investigate the therapeutic potential of HCS for the treatment of pancreatic cancer in in situ transplanted tumor nude mouse model. Furthermore, this study sought to elucidate the molecular mechanisms underlying its efficacy and assess the impact of HCS on the microenvironment of pancreatic cancer. To identify the antitumor effect of HCS in in situ transplanted tumor nude mouse model and determine the Chemopreventive mechanism of HCS on tumor microenvironment (TME). METHODS: Using the orthotopic transplantation nude mouse model with fluorescently labeled pancreatic cancer cell lines SW1990 and pancreatic stellate cells (PSCs), we examined the effect of HCS on the pancreatic ductal adenocarcinoma (PDAC) microenvironment based on the transforming growth factor ß (TGF-ß)/Smad pathway. The expression of TGF-ß, smad2, smad3, smad4, collagen type-1 genes and proteins in nude mouse model were detected by qRT-PCR and Western blot. RESULTS: HCS significantly reduced tumor growth rate, increased the survival rate, and ameliorated the histopathological changes in the pancreas. It was found that HCS concentration-dependently reduced the expression of TGF-ß1 and collagen type-1 genes and proteins, decreased the expression of Smad2 and Smad3 genes, and downregulated the phosphorylation level of Smad2/3. Additionally, the gene and protein expression of Smad4 were promoted by HCS. Further, the promoting effect gradually enhanced with the rise of HCS concentration. CONCLUSIONS: The results demonstrated HCS could regulate the activity of the TGF-ß/Smad pathway in PDAC, improved the microenvironment of PDAC and delayed tumor progression. This study not only indicated that the protective mechanism of HCS on PDAC might be attributed partly to the inhibition of cytokine production and the TGF-ß/Smad pathway, but also provided evidence for HCS as a potential medicine for PDAC treatment.

Arenobufagin, isolated from Bufo viridis toad venom, inhibits A549 cells proliferation by inducing apoptosis and G2/M cell cycle arrest.

Lung cancer is a significant contributor to cancer morbidity and mortality globally. Arenobufagin, a compound derived from Bufo viridis toad venom, has demonstrated the ability to inhibit cell growth in various cancer cell lines. However, our understanding of the role and mechanism of arenobufagin in lung cancer remains incomplete, necessitating further researches to fully elucidate its action mechanism. In this study, we further explored the impact of arenobufagin on A549 cells. The results revealed that it exerted a potent cytotoxic effect on A549 cells by inhibiting cell colony formation, promoting cell apoptosis, increasing reactive oxygen species (ROS) levels, and arresting A549 cells in G2/M phase. Collectively, our findings suggested that arenobufagin may have potential as a future therapeutic for lung cancer treatment.

Chemical Composition, Pharmacological Effects and Clinical Applications of Cinobufacini.

Chinese medicine cinobufacini is an extract from the dried skin of Bufo bufo gargarizans Cantor, with active ingredients of bufadienolides and indole alkaloids. With further research and clinical applications, it is found that cinobufacini alone or in combination with other therapeutic methods can play an anti-tumor role by controlling proliferation of tumor cells, promoting apoptosis, inhibiting formation of tumor neovascularization, reversing multidrug resistance, and regulating immune response; it also has the functions of relieving cancer pain and regulating immune function. In this paper, the chemical composition, pharmacological effects, clinical applications, and adverse reactions of cinobufacini are summarized. However, the extraction of monomer components of cinobufacini, the relationship between different mechanisms, and the causes of adverse reactions need to be further studied. Also, high-quality clinical studies should be conducted.

Compound-composed Chinese medicine of Huachansu triggers apoptosis of gastric cancer cells through increase of reactive oxygen species levels and suppression of proteasome activities.

BACKGROUND: Huachansu (HCS), a known Chinese patent drug extracted from the Chinese toad skin, is frequently used for the treatment of various advanced cancers, especially gastric cancer, due to the good therapeutic effect. However, it is rather difficult to clarify the active substances and molecular mechanisms involved owing to the lack of appropriate research strategies. We recently proposed the concept and research ideas of compound-composed Chinese medicine formula. PURPOSE: To discover compound-composed Chinese medicine from Huachansu and to explore its mechanism of action in inducing apoptosis of gastric cancer cells. METHOD: Network pharmacology combined with serum pharmacochemistry was utilized to screen the predominant active constituents from HCS against gastric cancer. Then, the compound-composed Chinese medicine of HCS (CCMH) was prepared according to their relative contents in serum. The pharmacological effects and potential mechanisms for CCMH were investigated by assays for cell viability, cell cycle, apoptosis, mitochondrial membrane potential (MMP), proteomics, reactive oxygen species (ROS), N-Acetylcysteine (NAC) antagonism, proteasome activity, and western blot. RESULTS: CCMH was comprised of arenobufagin (11.14%), bufalin (18.67%), bufotalin (7.33%), cinobufagin (16.67%), cinobufotalin (16.74%), gamabufotalin (8.45%), resibufogenin (12.03%), and telocinobufagin (8.97%). CCMH evidently induced proliferation inhibition, cell cycle arrest, apoptosis, and MMP collapse in gastric cancer cells, possessing the better activities than HCS. Proteomic analysis showed that CCMH influenced ROS pathway, ubiquitin proteasome system, and PI3K/Akt and MAPK signaling pathways. CCMH markedly enhanced intracellular ROS levels in gastric cancer cells, which was reversed by NAC. Accordingly, NAC antagonized the apoptosis-inducing effect of CCMH. Significantly decreased proteasome 20S activity by CCMH was observed in gastric cancer cells. CCMH also regulated the expression of key proteins in PI3K/Akt and MAPK signaling pathways. CONCLUSION: CCMH possesses more significant apoptotic induction effects on gastric cancer cells than HCS, which is achieved primarily through suppression of proteasome activities and increase of ROS levels, followed by regulating PI3K/Akt and MAPK signaling pathways. Network pharmacology combined with serum pharmacochemistry is an effective strategy for discovering compound-composed Chinese medicine from traditional Chinese medicine, which can help clarify the pharmacological substances and mechanisms of action for traditional Chinese medicine.

Exploring peptides from toad venom for source identification by LC-MS/MS using MRM method.

Toad venom is a traditional Chinese medicine (TCM) with various sources and wide-ranging preparations. Previous quality assessment studies primarily concentrated on small molecular compounds like toad dienolactones and indole alkaloids, studies on macromolecular peptides and proteins as quality assessment standards remained at the qualitative stage, lacking the development of practical and convenient quantitative methods. In this study, to explore the peptides from toad venom as a new method for identifying and evaluating its source, a complete scan of the water extract of peptides from toad venom was conducted using HPLC-Quadrupole Time-of-Flight Mass Spectrometer (Q-TOF) 5600, leading to the identification of peptides based on mass spectrometry data. Subsequently, HPLC- Quadrupole-Linear Ion Trap Mass Spectrometer (Q-Trap) 5500 employing Multiple Reaction Monitoring (MRM) mode was utilized to quantitatively analyze peptides in various sources of toad venom, followed by Partial Least Squares Discriminant Analysis (PLS-DA) to further analyze the data and evaluate the effectiveness. This study highlights the importance of exploring macromolecular substance in natural products research and provides a foundation for further studies on toad venom.

Efficacy and safety of Huachansu combined with adjuvant chemotherapy in resected colorectal cancer patients: a prospective, open-label, randomized phase II study.

Although some studies in China have suggested Huachansu (HCS) combined with chemotherapy is effective in the treatment of various cancers, there are few studies on colorectal cancer (CRC), especially in postoperative adjuvant chemotherapy. The aim of this study was to test the hypothesis that HCS combined with adjuvant chemotherapy would improve survival probability in resected CRC patients. This was a prospective, open-label, randomized phase II study. Patients with stage III or high-risk stage II resected CRC were randomly assigned to the chemotherapy and HCS + chemotherapy groups. The Chemotherapy group was treated with the FOLFOX regimen for ≥ 6 cycles or the CAPEOX regimen for ≥ 4 cycles. The HCS + chemotherapy group was treated with HCS on the basis of the chemotherapy group. The primary endpoint was 3-year disease-free survival (DFS), and the secondary endpoints were 3-year overall survival (OS) and toxicity. A total of 250 patients were included in this study (126 chemotherapy, 124 HCS + chemotherapy). There were significant differences in 3-year DFS between the two groups (median 28.7 vs. 31.6 months, respectively; P = 0.027), but no significant differences in 3-year OS between the two groups (median 32.7 vs. 34 months, respectively; P = 0.146). No patients experienced grade four adverse events, and the rates of leukopenia, neutropenia, and diarrhea in the HCS + chemotherapy group were lower than that those in the chemotherapy group. HCS combined with adjuvant chemotherapy after radical resection for patients with stage III or high-risk stage II CRC was demonstrated to be an effective and feasible treatment.

Pharmacological Effects of Cinobufagin.

Cinobufagin (CBF) is a bufadienolide, which is a major active ingredient of toad venom. In recent years, CBF has attracted increasing attention due to its highly potent and multiple pharmacological activities. To better understand the status of research on CBF, we collated recent studies on CBF to provide a valuable reference for clinical researchers and practitioners. According to reports, CBF exhibits extensive pharmacological properties, including antitumor, analgesic, cardioprotection, immunomodulatory, antifibrotic, antiviral, and antiprotozoal effects. Studies on the pharmacological activity of CBF have mainly focused on its anticancer activity. It has been demonstrated that CBF has a therapeutic effect on liver cancer, osteosarcoma, melanoma, colorectal cancer, acute promyelocytic leukemia, nasopharyngeal carcinoma, multiple myeloma, gastric cancer, and breast cancer. However, the direct molecular targets of CBF are currently unknown. In addition, there are few reports on toxicological and pharmacokinetic of CBF. Subsequent studies focusing on these aspects will help promote the development and application of CBF in clinical practice.

The Effects of Cinobufagin on Hepatocellular Carcinoma Cells Enhanced by MRT68921, an Autophagy Inhibitor.

Cinobufagin, a cardiotonic steroid derived from toad venom extracts, exhibits significant anticancer properties by inhibiting Na[Formula: see text]/K[Formula: see text]-ATPase in cancer cells. It is frequently used in clinical settings to treat advanced-stage cancer patients, improving their quality of life and survival time. However, its long-term use can result in multidrug resistance to other chemotherapy drugs, and the exact mechanism underlying this effect remains unknown. Therefore, this study explores the molecular mechanism underlying the anticancer effects of cinobufagin in hepatocellular carcinomas (HCCs), specifically in HepG2 and Huh-7 cells. As determined using transcriptome analysis, cinobufagin-triggered protective autophagy suppressed cell apoptosis in liver cancer HepG2 and Huh-7 cells by inhibiting the phosphoinositide-3-Kinase (PI3K)-AKT serine/threonine kinase (AKT)-mammalian target of rapamycin (mTOR) pathway. Cinobufagin-inhibited cell proliferation, induced apoptosis, and generated cell autophagy by upregulating the expression of MAP1 light chain 3 protein II, Beclin1, and autophagy-related protein 12-5. In addition, the autophagy inhibitor MRT68921 improved the antiproliferative and proapoptotic effects of cinobufagin in the studied cell lines. Overall, this study suggests that combining cinobufagin with an autophagy inhibitor can effectively treat HCC, providing a potential strategy for cancer therapy.

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.

Identification of Protein Quality Markers in Toad Venom from Bufo gargarizans.

Toad venom is a traditional Chinese medicine with high medicinal value. The existing quality evaluation standards of toad venom have obvious limitations because of the lack of research on proteins. Thus, it is necessary to screen suitable quality markers and establish appropriate quality evaluation methods for toad venom proteins to guarantee their safety and efficacy in clinical applications. SDS-PAGE, HPLC, and cytotoxicity assays were used to analyze differences in protein components of toad venom from different areas. Functional proteins were screened as potential quality markers by proteomic and bioinformatic analyses. The protein components and small molecular components of toad venom were not correlated in content. Additionally, the protein component had strong cytotoxicity. Proteomics analysis showed that 13 antimicrobial proteins, four anti-inflammatory and analgesic proteins, and 20 antitumor proteins were differentially expressed extracellular proteins. A candidate list of functional proteins was coded as potential quality markers. Moreover, Lysozyme C-1, which has antimicrobial activity, and Neuropeptide B (NPB), which has anti-inflammatory and analgesic activity, were identified as potential quality markers for toad venom proteins. Quality markers can be used as the basis of quality studies of toad venom proteins and help to construct and improve safe, scientific, and comprehensive quality evaluation methods.

Preliminary ionome of the parotoid gland secretion from Rhinella jimi toad.

The cururu toad (Rhinella jimi) is an anuran belonging to the fauna of the Brazilian northeast region, which releases a secretion with toxins from your parotoid glands. Although it has some information about secondary metabolites and proteins, the elemental composition of the released secretion is unknown. Therefore, this is the first report on the ionome of the secretion of the parotoid glands from R. jimi, investigating the influences of abiotic factors such as biome, seasonality, and gender. ICP-MS was used for measurements combined with principal component analysis (PCA). A screening of the secretion sample detected 68 elements which the total concentration of 18 elements was determined. PCA revealed that biome and seasonality factors have a greater influence on the ionomic profile of parotoid secretion. The presence of toxic metals in the secretion samples indicates that the R. jimi toad can be considered a potential bioindicator. These findings may contribute to understanding the metabolism, lifestyle, and interaction of the R. jimi toad with environmental factors as well as open new perspectives to investigate the relationships of the ionome with other biomolecules, for example, metalloproteins and their physiological functions.