Honokiol inhibits migration of renal cell carcinoma through activation of RhoA/ROCK/MLC signaling pathway

The role of natural products versus miRNA in renal cell carcinoma: implications for disease mechanisms and diagnostic markers

Natural products are chemical compounds produced by living organisms. They are isolated and purified to determine their function and can potentially be used as therapeutic agents. The ability of some bioactive natural products to modify the course of cancer is fascinating and promising. In the past 50 years, there have been advancements in cancer therapy that have increased survival rates for localized tumors. However, there has been little progress in treating advanced renal cell carcinoma (RCC), which is resistant to radiation and chemotherapy. Oncogenes and tumor suppressors are two roles played by microRNAs (miRNAs). They are involved in important pathogenetic mechanisms like hypoxia and epithelial-mesenchymal transition (EMT); they control apoptosis, cell growth, migration, invasion, angiogenesis, and proliferation through target proteins involved in various signaling pathways. Depending on their expression pattern, miRNAs may identify certain subtypes of RCC or distinguish tumor tissue from healthy renal tissue. As diagnostic biomarkers of RCC, circulating miRNAs show promise. There is a correlation between the expression patterns of several miRNAs and the prognosis and diagnosis of patients with RCC. Potentially high-risk primary tumors may be identified by comparing original tumor tissue with metastases. Variations in miRNA expression between treatment-sensitive and therapy-resistant patients' tissues and serum allow for the estimation of responsiveness to target therapy. Our knowledge of miRNAs' function in RCC etiology has a tremendous uptick. Finding and validating their gene targets could have an immediate effect on creating anticancer treatments based on miRNAs. Several miRNAs have the potential to be used as biomarkers for diagnosis and prognosis. This review provides an in-depth analysis of the current knowledge regarding natural compounds and their modes of action in combating cancer. Also, this study aims to give information about the diagnostic and prognostic value of miRNAs as cancer biomarkers and their involvement in the pathogenesis of RCC.

ZC3H4 governs epithelial cell migration through ROCK/p-PYK2/p-MLC2 pathway in silica-induced pulmonary fibrosis

BACKGROUND

Increased epithelial migration capacity is a key step accompanying epithelial-mesenchymal transition (EMT). Our lab has described that ZC3H4 mediated EMT in silicosis. Here, we aimed to explore the mechanisms of ZC3H4 by which to stimulate epithelial cell migration.

METHODS

Silicon dioxide (SiO2)-induced pulmonary fibrosis (PF) animal models were administered by intratracheal instillation in C57BL/6 J mice. Pathological analysis and 2D migration assay were established to uncover the pulmonary fibrotic lesions and epithelial cell migration, respectively. Inhibitors targeting ROCK/p-PYK2/p-MLC2 and CRISPR/Cas9 plasmids targeting ZC3H4 were administrated to explore the signaling pathways.

RESULTS

1) SiO2 upregulated epithelial migration in pulmonary fibrotic lesions. 2) ZC3H4 modulated SiO2-induced epithelial migration. 3) ZC3H4 governed epithelial migration through ROCK/p-PYK2/p-MLC2 signaling pathway.

CONCLUSIONS

ZC3H4 regulates epithelial migration through the ROCK/p-PYK2/p-MLC2 signaling pathway, providing the possibility that molecular drugs targeting ZC3H4-overexpression may exert effects on pulmonary fibrosis induced by silica.

Pharmacological features, health benefits and clinical implications of honokiol

Honokiol (HNK) is a natural polyphenolic compound extracted from the bark and leaves of Magnolia grandiflora. It has been traditionally used as a medicinal compound to treat inflammatory diseases. HNK possesses numerous health benefits with a minimal level of toxicity. It can cross the blood-brain barrier and blood-cerebrospinal fluid, thus having significant bioavailability in the neurological tissues. HNK is a promising bioactive compound possesses neuroprotective, antimicrobial, anti-tumorigenic, anti-spasmodic, antidepressant, analgesic, and antithrombotic features . HNK can prevent the growth of several cancer types and haematological malignancies. Recent studies suggested its role in COVID-19 therapy. It binds effectively with several molecular targets, including apoptotic factors, chemokines, transcription factors, cell surface adhesion molecules, and kinases. HNK has excellent pharmacological features and a wide range of chemotherapeutic effects, and thus, researchers have increased interest in improving the therapeutic implications of HNK to the clinic as a novel agent. This review focused on the therapeutic implications of HNK, highlighting clinical and pharmacological features and the underlying mechanism of action.Communicated by Ramaswamy H. Sarma.

Honokiol inhibits the growth of hormone-resistant breast cancer cells: its promising effect in combination with metformin

Background and purpose

Primary and metastatic breast cancers still represent an unmet clinical need for improved chemotherapy and hormone therapy. Considerable attention has been paid to natural anticancer compounds, especially lignans. The study aimed to evaluate the activity of several lignans against breast cancer cells and assess the effect of leading lignans on signaling pathways in combination with metformin.

Experimental approach

Human breast cancer cell lines MCF7 (hormone-dependent), MDA-MB-231, and SKBR3 (hormone-independent) were used. A hormone-resistant MCF7/hydroxytamoxifen (HT) subline was obtained by long-term cultivation of the MCF7 line with hydroxytamoxifen. Antiproliferative activity was assessed by the MTT test; the expression of signaling pathway proteins was evaluated by immunoblotting analysis.

Findings/Results

We evaluated the antiproliferative activity of lignans in breast cancer cells with different levels of hormone dependence and determined the relevant IC50 values. Honokiol was chosen as the leading compound, and its IC50 ranged from 12 to 20 μM, whereas for other tested lignans, the IC50 exceeded 50 μM. The accumulation of cleaved PARP and a decrease in the expression of Bcl-2 and ERα in MCF7/HT were induced following the combination of honokiol with metformin.

Conclusions and implications

Honokiol demonstrated significant antiproliferative activity against both hormone-dependent breast cancer cells and lines with primary and acquired hormone resistance. The combination of honokiol with metformin is considered an effective approach to induce death in hormone-resistant cells. Honokiol is of interest as a natural compound with antiproliferative activity against breast cancers, including resistant tumors.

Natural Compounds Derived from Plants on Prevention and Treatment of Renal Cell Carcinoma: A Literature Review

Renal cell carcinoma (RCC) accounts for roughly 85% of all malignant kidney cancer. Therapeutic options for RCC have expanded rapidly over the past decade. Targeted therapy and immunotherapy have ushered in a new era of the treatment of RCC, which has facilitated the outcomes of RCC. However, the related adverse effects and drug resistance remain an urgent issue. Natural compounds are optional strategies to reduce mobility. Natural compounds are favored by clinicians and researchers due to their good tolerance and low economic burden. Many studies have explored the anti-RCC activity of natural products and revealed relevant mechanisms. In this article, the chemoprevention and therapeutic potential of natural compounds is reviewed and the mechanisms regarding natural compounds are explored.

Jamming Transitions in Astrocytes and Glioblastoma Are Induced by Cell Density and Tension

Collective behavior of cells emerges from coordination of cell-cell-interactions and is important to wound healing, embryonic and tumor development. Depending on cell density and cell-cell interactions, a transition from a migratory, fluid-like unjammed state to a more static and solid-like jammed state or vice versa can occur. Here, we analyze collective migration dynamics of astrocytes and glioblastoma cells using live cell imaging. Furthermore, atomic force microscopy, traction force microscopy and spheroid generation assays were used to study cell adhesion, traction and mechanics. Perturbations of traction and adhesion were induced via ROCK or myosin II inhibition. Whereas astrocytes resided within a non-migratory, jammed state, glioblastoma were migratory and unjammed. Furthermore, we demonstrated that a switch from an unjammed to a jammed state was induced upon alteration of the equilibrium between cell-cell-adhesion and tension from adhesion to tension dominated, via inhibition of ROCK or myosin II. Such behavior has implications for understanding the infiltration of the brain by glioblastoma cells and may help to identify new strategies to develop anti-migratory drugs and strategies for glioblastoma-treatment.

Phytochemicals for the Prevention and Treatment of Renal Cell Carcinoma: Preclinical and Clinical Evidence and Molecular Mechanisms

Simple Summary

Renal cell carcinoma (RCC) is the most frequently diagnosed kidney cancer. Once RCC metastasizes, successful treatment is difficult to achieve. There is an apparent need for novel approaches to prevent and treat RCC. Phytochemicals are naturally derived compounds gaining increasing scientific interest due to their cancer preventive and chemotherapeutic properties. These phytochemicals have been shown to exhibit a multitude of anticancer effects against RCC. In this systematic review, we critically evaluate the potential these natural compounds possess for the prevention and treatment of RCC and discuss the future implications this may have in the fight against kidney cancer.

Abstract

Renal cell carcinoma (RCC) is associated with about 90% of renal malignancies, and its incidence is increasing globally. Plant-derived compounds have gained significant attention in the scientific community for their preventative and therapeutic effects on cancer. To evaluate the anticancer potential of phytocompounds for RCC, we compiled a comprehensive and systematic review of the available literature. Our work was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria. The literature search was performed using scholarly databases such as PubMed, Scopus, and ScienceDirect and keywords such as renal cell carcinoma, phytochemicals, cancer, tumor, proliferation, apoptosis, prevention, treatment, in vitro, in vivo, and clinical studies. Based on in vitro results, various phytochemicals, such as phenolics, terpenoids, alkaloids, and sulfur-containing compounds, suppressed cell viability, proliferation and growth, showed cytotoxic activity, inhibited invasion and migration, and enhanced the efficacy of chemotherapeutic drugs in RCC. In various animal tumor models, phytochemicals suppressed renal tumor growth, reduced tumor size, and hindered angiogenesis and metastasis. The relevant antineoplastic mechanisms involved upregulation of caspases, reduction in cyclin activity, induction of cell cycle arrest and apoptosis via modulation of a plethora of cell signaling pathways. Clinical studies demonstrated a reduced risk for the development of kidney cancer and enhancement of the efficacy of chemotherapeutic drugs. Both preclinical and clinical studies displayed significant promise of utilizing phytochemicals for the prevention and treatment of RCC. Further research, confirming the mechanisms and regulatory pathways, along with randomized controlled trials, are needed to establish the use of phytochemicals in clinical practice.

Honokiol Suppresses Perineural Invasion of Pancreatic Cancer by Inhibiting SMAD2/3 Signaling

Background

Perineural invasion (PNI) is an important pathologic feature of pancreatic cancer, and the incidence of PNI in pancreatic cancer is 70%-100%. PNI is associated with poor outcome, metastasis, and recurrence in pancreatic cancer patients. There are very few treatments for PNI in pancreatic cancer. Honokiol (HNK) is a natural product that is mainly obtained from Magnolia species and has been indicated to have anticancer activity. HNK also has potent neurotrophic activity and may be effective for suppressing PNI. However, the potential role of HNK in the treatment of PNI in pancreatic cancer has not been elucidated.

Methods

In our study, pancreatic cancer cells were treated with vehicle or HNK, and the invasion and migration capacities were assessed by wound scratch assays and Transwell assays. A cancer cell-dorsal root ganglion coculture model was established to evaluate the effect of HNK on the PNI of pancreatic cancer. Western blotting was used to detect markers of EMT and neurotrophic factors in pancreatic tissue. Recombinant TGF-β1 was used to activate SMAD2/3 to verify the effect of HNK on SMAD2/3 and neurotrophic factors. The subcutaneous tumor model and the sciatic nerve invasion model, which were established in transgenic engineered mice harboring spontaneous pancreatic cancer, were used to investigate the mechanism by which HNK inhibits EMT and PNI in vivo.

Results

We found that HNK can inhibit the invasion and migration of pancreatic cancer cells. More importantly, HNK can inhibit the PNI of pancreatic cancer. The HNK-mediated suppression of pancreatic cancer PNI was partially mediated by inhibition of SMAD2/3 phosphorylation. In addition, the inhibitory effect of HNK on PNI can be reversed by activating SMAD2/3. In vivo, we found that HNK can suppress EMT in pancreatic cancer. HNK can also inhibit cancer cell migration along the nerve, reduce the damage to the sciatic nerve caused by tumor cells and protect the function of the sciatic nerve.

Conclusion

Our results demonstrate that HNK can inhibit the invasion, migration, and PNI of pancreatic cancer by blocking SMAD2/3 phosphorylation, and we conclude that HNK may be a new strategy for suppressing PNI in pancreatic cancer.

Honokiol: A review of its pharmacological potential and therapeutic insights

BACKGROUND

Honokiol is a pleiotropic compound which been isolated from Magnolia species such as Magnolia grandiflora and Magnolia dealbata. Magnolia species Magnolia grandiflora is used in traditional medicine for the treatment of various diseases.

PURPOSE

The objective of this review is to summarize the pharmacological potential and therapeutic insights of honokiol.

STUDY DESIGN

Honokiol has been specified as a novel alternative to treat various disorders such as liver cancer, neuroprotective, anti-spasmodic, antidepressant, anti-tumorigenic, antithrombotic, antimicrobial, analgesic properties and others. Therefore, this study designed to represent the in-depth therapeutic potential of honokiol.

METHODS

Literature searches in electronic databases, such as Web of Science, Science Direct, PubMed, Google Scholar, and Scopus, were performed using the keywords 'Honokiol', 'Health Benefits' and 'Therapeutic Insights' as the keywords for primary searches and secondary search terms were used as follows: 'Anticancer', 'Oxidative Stress', 'Neuroprotective', 'Antimicrobial', 'Cardioprotection', 'Hepatoprotective', 'Anti-inflammatory', 'Arthritis', 'Reproductive Disorders'.

RESULTS

This promising bioactive compound presented an wide range of therapeutic and biological activities which include liver cancer, neuroprotective, anti-spasmodic, antidepressant, anti-tumorigenic, antithrombotic, antimicrobial, analgesic properties, and others. Its pharmacokinetics has been established in experimental animals, while in humans, this is still speculative. Some of its mechanism for exhibiting its pharmacological effects includes apoptosis of diseased cells, reduction in the expression of defective proteins like P-glycoproteins, inhibition of oxidative stress, suppression of pro-inflammatory cytokines (TNF-α, IL-10 and IL-6), amelioration of impaired hepatic enzymes and reversal of morphological alterations, among others.

CONCLUSION

All these actions displayed by this novel compound could make it serve as a lead in the formulation of drugs with higher efficacy and negligible side effects utilized in the treatment of several human diseases.

Honokiol: A Review of Its Anticancer Potential and Mechanisms

Cancer is characterised by uncontrolled cell division and abnormal cell growth, which is largely caused by a variety of gene mutations. There are continuous efforts being made to develop effective cancer treatments as resistance to current anticancer drugs has been on the rise. Natural products represent a promising source in the search for anticancer treatments as they possess unique chemical structures and combinations of compounds that may be effective against cancer with a minimal toxicity profile or few side effects compared to standard anticancer therapy. Extensive research on natural products has shown that bioactive natural compounds target multiple cellular processes and pathways involved in cancer progression. In this review, we discuss honokiol, a plant bioactive compound that originates mainly from the Magnolia species. Various studies have proven that honokiol exerts broad-range anticancer activity in vitro and in vivo by regulating numerous signalling pathways. These include induction of G0/G1 and G2/M cell cycle arrest (via the regulation of cyclin-dependent kinase (CDK) and cyclin proteins), epithelial-mesenchymal transition inhibition via the downregulation of mesenchymal markers and upregulation of epithelial markers. Additionally, honokiol possesses the capability to supress cell migration and invasion via the downregulation of several matrix-metalloproteinases (activation of 5' AMP-activated protein kinase (AMPK) and KISS1/KISS1R signalling), inhibiting cell migration, invasion, and metastasis, as well as inducing anti-angiogenesis activity (via the down-regulation of vascular endothelial growth factor (VEGFR) and vascular endothelial growth factor (VEGF)). Combining these studies provides significant insights for the potential of honokiol to be a promising candidate natural compound for chemoprevention and treatment.

Nanoparticulated Honokiol Mitigates Cisplatin-Induced Chronic Kidney Injury by Maintaining Mitochondria Antioxidant Capacity and Reducing Caspase 3-Associated Cellular Apoptosis

Cisplatin is a potent anti-cancer drug, however, its accompanied organ-toxicity hampers its clinical applications. Cisplatin-associated kidney injury is known to result from its accumulation in the renal tubule with excessive generation of reactive oxygen species. In this study, we encapsulated honokiol, a natural lipophilic polyphenol constituent extracted from Magnolia officinalis into nano-sized liposomes (nanosome honokiol) and examined the in vivo countering effects on cisplatin-induced renal injury. We observed that 5 mg/kg body weight. nanosome honokiol was the lowest effective dosage to efficiently restore renal functions of cisplatin-treated animals. The improvement is likely due the maintenance of cellular localization of cytochrome c and thus preserves mitochondria integrity and their redox activity, which as a consequence, reduced cellular oxidative stress and caspase 3-associated apoptosis. These improvements at the cellular level are later reflected on the observed reduction of kidney inflammation and fibrosis. In agreement with our earlier in vitro study showing protective effects of honokiol on kidney cell lines, we demonstrated further in the current study, that nanosuspension-formulated honokiol provides protective effects against cisplatin-induced chronic kidney damages in vivo. Our findings not only benefit cisplatin-receiving patients with reduced renal side effects, but also provide potential alternative and synergic solutions to improve clinical safety and efficacy of cisplatin treatment on cancer patients.

Inhibition of motility by NEO100 through the calpain-1/RhoA pathway

OBJECTIVE

Glioblastoma (GBM) is the most aggressive type of brain tumor with a high rate of tumor recurrence, and it often develops resistance over time to current standard of care chemotherapy. Its highly invasive nature plays an essential role in tumor progression and recurrence. Glioma stem cells (GSCs) are a subpopulation of glioma cells highly resistant to treatments and are considered responsible for tumor recurrence.

METHODS

Patient-derived populations of GSCs were analyzed by western blot, MTT, and cytoplasmic calcium labeling to determine the cytotoxicity of NEO100. High-performance liquid chromatography was used to evaluate the levels of NEO100 in the cell culture supernatants. The effects of the compound on GSC motility were studied using Boyden chamber migration, 3D spheroid migration and invasion assays, and an mRNA expression PCR array. A RhoA activation assay, western blot, and immunofluorescence techniques were employed to confirm the signaling pathways involved. Intracranial implantation of GSCs in athymic mice was used to evaluate the effects of NEO100 in vivo on tumor progression and overall survival.

RESULTS

Here, the authors show how NEO100, a highly purified good manufacturing practices-quality form of perillyl alcohol, is cytotoxic for different subtypes of GSCs, regardless of the mechanisms of DNA repair present. At doses similar to the IC50 (half maximal inhibitory concentration) values, NEO100 induces ER stress and activates apoptotic pathways in all GSC populations tested. At subcytotoxic doses in the micromolar range, NEO100 blocks migration and invasion of GSCs. These results correlate with a decrease in calpain-1 expression and an increase in RhoA activation, leading to enhanced contractility of the GSCs. In addition, NEO100 blocks the activation of the kinases Src, p42/44 MAPK, Akt, and Stat3, all related to cell proliferation and migration. Intranasal administration of NEO100 in mice with GSC-derived intracranial tumors led to a decrease in tumor progression and a 32% increase in overall survival. Immunostaining studies showed that NEO100 induces apoptosis and reduces GSC invasion in vivo.

CONCLUSIONS

NEO100 could have significant value targeting GSCs and could be used for GBM therapy as either monotherapy or a coadjuvant therapy during temozolomide rest cycles.

The Cytoskeleton-A Complex Interacting Meshwork

The cytoskeleton of animal cells is one of the most complicated and functionally versatile structures, involved in processes such as endocytosis, cell division, intra-cellular transport, motility, force transmission, reaction to external forces, adhesion and preservation, and adaptation of cell shape. These functions are mediated by three classical cytoskeletal filament types, as follows: Actin, microtubules, and intermediate filaments. The named filaments form a network that is highly structured and dynamic, responding to external and internal cues with a quick reorganization that is orchestrated on the time scale of minutes and has to be tightly regulated. Especially in brain tumors, the cytoskeleton plays an important role in spreading and migration of tumor cells. As the cytoskeletal organization and regulation is complex and many-faceted, this review aims to summarize the findings about cytoskeletal filament types, including substructures formed by them, such as lamellipodia, stress fibers, and interactions between intermediate filaments, microtubules and actin. Additionally, crucial regulatory aspects of the cytoskeletal filaments and the formed substructures are discussed and integrated into the concepts of cell motility. Even though little is known about the impact of cytoskeletal alterations on the progress of glioma, a final point discussed will be the impact of established cytoskeletal alterations in the cellular behavior and invasion of glioma.

Simvastatin reduces the carcinogenic effect of 3-methylcholanthrene in renal epithelial cells through histone deacetylase 1 inhibition and RhoA reactivation

The therapeutic effects of simvastatin for renal cell carcinoma (RCC) are controversial. In this study, the effects of simvastatin on the carcinogenic properties of 3-methylcholanthrene (3MC; an aryl-hydrocarbon receptor [AhR] agonist) in human renal epithelial cells (hRECs) were investigated. We exposed in vitro and in vivo models to 3MC to induce RCC onset. 3MC upregulated the epithelial-mesenchymal transition (EMT) and tumor biomarkers; the models exhibited the reciprocal expression of histone deacetylase 1 (HDAC1) and RhoA, namely increased HDAC1 and decreased RhoA expression, through hypoxia-inducible-factor (HIF)- and AhR-dependent mechanisms. In addition to inducing EMT biomarkers, 3MC decreased von Hippel-Lindau protein levels (a risk factor for RCC) and increased CD44 expression in hRECs, which were reversed by digoxin (a HIF inhibitor) and HDAC inhibitors (suberoylanilide hydroxamic acid and trichostatin A [TSA]). Simvastatin abolished the detrimental effects of 3MC by reducing HDAC1 expression, with resulting RhoA upregulation, and reactivating RhoA in vitro and in vivo. Notably, the protective effects of simvastatin were negated by an HDAC activator (ITSA) through TSA suppression. The crucial role of RhoA in RCC carcinogenesis was verified by the overexpression of constitutively active RhoA. Collectively, these results demonstrate that simvastatin restores RhoA function through HDAC1 inhibition; therefore, simvastatin might serve as adjunct therapy for RCC induced by 3MC.

Global proteomics profiling improves drug sensitivity prediction: results from a multi-omics, pan-cancer modeling approach

Motivation

Proteomics profiling is increasingly being used for molecular stratification of cancer patients and cell-line panels. However, systematic assessment of the predictive power of large-scale proteomic technologies across various drug classes and cancer types is currently lacking. To that end, we carried out the first pan-cancer, multi-omics comparative analysis of the relative performance of two proteomic technologies, targeted reverse phase protein array (RPPA) and global mass spectrometry (MS), in terms of their accuracy for predicting the sensitivity of cancer cells to both cytotoxic chemotherapeutics and molecularly targeted anticancer compounds.

Results

Our results in two cell-line panels demonstrate how MS profiling improves drug response predictions beyond that of the RPPA or the other omics profiles when used alone. However, frequent missing MS data values complicate its use in predictive modeling and required additional filtering, such as focusing on completely measured or known oncoproteins, to obtain maximal predictive performance. Rather strikingly, the two proteomics profiles provided complementary predictive signal both for the cytotoxic and targeted compounds. Further, information about the cellular-abundance of primary target proteins was found critical for predicting the response of targeted compounds, although the non-target features also contributed significantly to the predictive power. The clinical relevance of the selected protein markers was confirmed in cancer patient data. These results provide novel insights into the relative performance and optimal use of the widely applied proteomic technologies, MS and RPPA, which should prove useful in translational applications, such as defining the best combination of omics technologies and marker panels for understanding and predicting drug sensitivities in cancer patients.

Availability and implementation

Processed datasets, R as well as Matlab implementations of the methods are available at https://github.com/mehr-een/bemkl-rbps.

Contact

mehreen.ali@helsinki.fi or tero.aittokallio@fimm.fi.

Supplementary information

Supplementary data are available at Bioinformatics online.

Honokiol induces apoptosis of lung squamous cell carcinoma by targeting FGF2-FGFR1 autocrine loop

Lung squamous cell carcinoma (SCC) accounts for a considerable proportion of lung cancer cases, but there is still a lack of effective therapies. FGFR1 amplification is generally considered a promising therapeutic target. Honokiol is a chemical compound that has been proven to be effective against various malignancies and whose analog has been reported to target the mitogen‐activated protein kinase family, members of a downstream signaling pathway of FGFR1. This was an explorative study to determine the mechanism of honokiol in lung SCC. We found that honokiol induced apoptosis and cell cycle arrest in lung SCC cell lines in a time‐ and dose‐dependent manner. Honokiol also restricted cell migration in lung SCC cell lines. Moreover, the expression of FGF2 and the activation of FGFR1 were both downregulated by honokiol. Pharmacological inhibition and siRNA knockdown of FGFR1 induced apoptosis in lung SCC cells. Our in vivo study indicated that honokiol could suppress the growth of xenograft tumors, and this effect was associated with the inhibition of the FGF2‐FGFR1 signaling pathway. In conclusion, honokiol induced cell apoptosis in lung SCC by targeting the FGF2‐FGFR1 autocrine loop.

Honokiol, a Polyphenol Natural Compound, Attenuates Cisplatin-Induced Acute Cytotoxicity in Renal Epithelial Cells Through Cellular Oxidative Stress and Cytoskeleton Modulations

Cisplatin is a potent anti-cancer drug that has been widely used in the treatment of various cancers; however, cisplatin administration results in severe nephrotoxicity and impedes its clinical applications. In this study, we showed that honokiol, a polyphenol constituent extracted from Magnolia officinalis exhibited a short-term protective effect against cisplatin-induced damages in renal epithelial cells in vitro. The protective effects of honokiol were resulted from the combination of (1) reduced cellular oxidative stress ranging from 53 to 32% reduction during a 24-h incubation, (2) the maintenance of cellular antioxidant capacity and (3) the stabilization of cytoskeletal structure of the kidney epithelial cells. By promoting the polymerization of actin (1.6-fold increase) and tubulin (1.8-fold increase) cytoskeleton, honokiol not only maintained epithelial cell morphology, but also stabilized cellular localizations of tight junction protein Occludin and adhesion junction protein E-Cadherin. With stabilized junction protein complexes and structural polymerized cytoskeleton network, honokiol preserved epithelial cell polarity and morphology and thus reduced cisplatin-induced cell disruption and damages. Our data demonstrated for the first time that honokiol could counteract with cisplatin-induced damages in renal epithelial cells in vitro, future in vivo studies would further validate the potential clinical application of honokiol in cisplatin-based cancer treatments with reduced nephrotoxicity.

Honokiol inhibits in vitro and in vivo growth of oral squamous cell carcinoma through induction of apoptosis, cell cycle arrest and autophagy

Honokiol, an active natural product derived from Magnolia officinalis, exerted anticancer effects through a variety of mechanisms on multiple types of cancers. In this study, the molecular mechanisms of honokiol in suppressing the human oral squamous cell carcinoma (OSCC) cells were evaluated. Treatment of two OSCC cell lines with honokiol resulted in reducing the cell proliferation and arresting the cell cycle at G1 stage which was correlated with the down‐regulation of Cdk2 and Cdk4 and the up‐regulation of cell cycle suppressors, p21 and p27. In addition, the caspase‐dependent programmed cell death was substantially detected, and the autophagy was induced as the autophagosome formation and autophagic flux proceeded. Modulation of autophagy by autophagic inducer, rapamycin or inhibitors, 3‐MA or bafilomycin, potentiated the honokiol‐mediated anti‐OSCC effects where honokiol exerted multiple actions in suppression of MAPK pathway and regulation of Akt/mTOR or AMPK pathways. As compared to clinical therapeutic agent, 5‐FU, honokiol exhibited more potent activity against OSCC cells and synergistically enhanced the cytotoxic effect of 5‐FU. Furthermore, orally administrated honokiol exerted effective antitumour activity in vivo in OSCC‐xenografted mice. Thus, this study revealed that honokiol could be a promising candidate in preventing human OSCCs.

The Role of Compounds Derived from Natural Supplement as Anticancer Agents in Renal Cell Carcinoma: A Review

Renal Cell Carcinoma (RCC) is the most prominent kidney cancer derived from renal tubules and accounts for roughly 85% of all malignant kidney cancer. Every year, over 60,000 new cases are registered, and about 14,000 people die from RCC. The incidence of this has been increasing significantly in the U.S. and other countries. An increased understanding of molecular biology and the genomics of RCC has uncovered several signaling pathways involved in the progression of this cancer. Significant advances in the treatment of RCC have been reported from agents approved by the Food and Drug Administration (FDA) that target these pathways. These agents have become drugs of choice because they demonstrate clinical benefit and increased survival in patients with metastatic disease. However, the patients eventually relapse and develop resistance to these drugs. To improve outcomes and seek approaches for producing long-term durable remission, the search for more effective therapies and preventative strategies are warranted. Treatment of RCC using natural products is one of these strategies to reduce the incidence. However, recent studies have focused on these chemoprevention agents as anti-cancer therapies given they can inhibit tumor cell grow and lack the severe side effects common to synthetic compounds. This review elaborates on the current understanding of natural products and their mechanisms of action as anti-cancer agents. The present review will provide information for possible use of these products alone or in combination with chemotherapy for the prevention and treatment of RCC.