Specific targeting of Wnt/β-catenin signaling in human melanoma cells by a dietary triterpene lupeol

Chemotherapeutic potential of lupeol against cancer in pre-clinical model: A systematic review and meta-analysis

BACKGROUND

Extensive research on Lupeol's potential in cancer prevention highlights its ability to target various cancer-related factors. It regulates proliferative markers, modulates signaling pathways, including PI3K/AKT/mTOR, and influences inflammatory and apoptotic mechanisms. Additionally, Lupeol demonstrates selectivity in killing cancer cells while sparing normal cells, thus minimizing the risk of toxic effects on healthy tissues.

HYPOTHESIS

Therefore, we aimed to explore Lupeol's potential roles as a chemotherapeutic agent and as a sensitizer to chemotherapy by reviewing various animal-based studies published on its effects.

STUDY DESIGN

We conducted a comprehensive search across databases, including PubMed, PMC, Cochrane, EuroPMC, and ctri.gov.in to identify pertinent articles. Our focus was solely on published animal studies examining Lupeol's anti-cancer effects, with reviewers independently assessing bias risk and resolving discrepancies through consensus.

RESULT

20 studies were shortlisted. The results demonstrated that Lupeol brings changes in the tumor volume by [Hedges's g: -6.62; 95 % CI: -8.68, -4.56; τ2: 24.36, I2: 96.50 %; p < 0.05] and tumor weight by [Hedges's g: -3.97; 95 % CI: -5.20, -2.49; τ2: 2.70, I2: 79.27 %; p <0.05]. The high I2, negative Egger's value, and asymmetrical funnel plot show the publication bias among the studies. Further, Lupeol in combination with other chemotherapeutic agents showed better outcomes as compared to them alone [Hedges's g: -6.38; 95 % CI: -11.82, -0.94; τ2: 46.91; I2: 98.68 %; p <0.05]. Lupeol also targets various signaling molecules and pathways to exert an anti-cancer effect.

CONCLUSION

In conclusion, Lupeol significantly reduces tumor volume and weight. Combining Lupeol with other chemotherapy agents shows promise for enhancing anti-cancer effects. However, high variability among studies and evidence of publication bias suggest caution in interpreting results.

The Emerging Role of Natural Products in Cancer Treatment

The exploration of natural products as potential agents for cancer treatment has garnered significant attention in recent years. In this comprehensive review, we delve into the diverse array of natural compounds, including alkaloids, carbohydrates, flavonoids, lignans, polyketides, saponins, tannins, and terpenoids, highlighting their emerging roles in cancer therapy. These compounds, derived from various botanical sources, exhibit a wide range of mechanisms of action, targeting critical pathways involved in cancer progression such as cell proliferation, apoptosis, angiogenesis, and metastasis. Through a meticulous examination of preclinical and clinical studies, we provide insights into the therapeutic potential of these natural products across different cancer types. Furthermore, we discuss the advantages and challenges associated with their use in cancer treatment, emphasizing the need for further research to optimize their efficacy, pharmacokinetics, and delivery methods. Overall, this review underscores the importance of natural products in advancing cancer therapeutics and paves the way for future investigations into their clinical applications.

Ischemia-reperfusion injury: molecular mechanisms and therapeutic targets

Ischemia-reperfusion (I/R) injury paradoxically occurs during reperfusion following ischemia, exacerbating the initial tissue damage. The limited understanding of the intricate mechanisms underlying I/R injury hinders the development of effective therapeutic interventions. The Wnt signaling pathway exhibits extensive crosstalk with various other pathways, forming a network system of signaling pathways involved in I/R injury. This review article elucidates the underlying mechanisms involved in Wnt signaling, as well as the complex interplay between Wnt and other pathways, including Notch, phosphatidylinositol 3-kinase/protein kinase B, transforming growth factor-β, nuclear factor kappa, bone morphogenetic protein, N-methyl-D-aspartic acid receptor-Ca2+-Activin A, Hippo-Yes-associated protein, toll-like receptor 4/toll-interleukine-1 receptor domain-containing adapter-inducing interferon-β, and hepatocyte growth factor/mesenchymal-epithelial transition factor. In particular, we delve into their respective contributions to key pathological processes, including apoptosis, the inflammatory response, oxidative stress, extracellular matrix remodeling, angiogenesis, cell hypertrophy, fibrosis, ferroptosis, neurogenesis, and blood-brain barrier damage during I/R injury. Our comprehensive analysis of the mechanisms involved in Wnt signaling during I/R reveals that activation of the canonical Wnt pathway promotes organ recovery, while activation of the non-canonical Wnt pathways exacerbates injury. Moreover, we explore novel therapeutic approaches based on these mechanistic findings, incorporating evidence from animal experiments, current standards, and clinical trials. The objective of this review is to provide deeper insights into the roles of Wnt and its crosstalk signaling pathways in I/R-mediated processes and organ dysfunction, to facilitate the development of innovative therapeutic agents for I/R injury.

Progress in Antimelanoma Research of Natural Triterpenoids and Their Derivatives: Mechanisms of Action, Bioavailability Enhancement and Structure Modifications

Melanoma is one of the most dangerous forms of skin cancer, characterized by early metastasis and rapid development. In search for effective treatment options, much attention is given to triterpenoids of plant origin, which are considered promising drug candidates due to their well described anticancer properties and relatively low toxicity. This paper comprehensively summarizes the antimelanoma potential of natural triterpenoids, that are also used as scaffolds for the development of more effective derivatives. These include betulin, betulinic acid, ursolic acid, maslinic acid, oleanolic acid, celastrol and lupeol. Some lesser-known triterpenoids that deserve attention in this context are 22β-hydroxytingenone, cucurbitacins, geoditin A and ganoderic acids. Recently described mechanisms of action are presented, together with the results of preclinical in vitro and in vivo studies, as well as the use of drug delivery systems and pharmaceutical technologies to improve the bioavailability of triterpenoids. This paper also reviews the most promising structural modifications, based on structure-activity observations. In conclusion, triterpenoids of plant origin and some of their semi-synthetic derivatives exert significant cytotoxic, antiproliferative and chemopreventive effects that can be beneficial for melanoma treatment. Recent data indicate that their poor solubility in water, and thus low bioavailability, can be overcome by complexing with cyclodextrins, or the use of nanoparticles and ethosomes, thus making these compounds promising antimelanoma drug candidates for further development.

Anticancer effect of terpenes: focus on malignant melanoma

Melanoma is a highly aggressive and life-threatening form of skin cancer that accounts for a significant proportion of cancer-related deaths worldwide. Although conventional cancer therapies, such as surgical excision, chemotherapy, and radiation, have been used to treat malignant melanoma, their efficacy is often limited due to the development of resistance and adverse side effects. Therefore, there is a growing interest in developing alternative treatment options for melanoma that are more effective and less toxic. Terpenes, a diverse group of naturally occurring compounds of plant origin, have emerged as potential anticancer agents due to their ability to inhibit tumor growth and induce apoptosis in cancer cells. In this review, the current understanding of the anticancer effects of terpenes (including, thymoquinone, β-elemene, carvacrol, limonene, α-pinene, β-caryophyllene, perillyl alcohol, taxol, betulinic acid, α-bisabolol, ursolic acid, linalool, lupeol, and artesunate) was summarized, with a special focus on their potential as therapeutic agents for malignant melanoma.

The β-catenin/CBP signaling axis participates in sepsis-induced inflammatory lung injury

Sepsis-induced inflammatory lung injury is a key factor causing failure of the lungs and other organs, as well as death, during sepsis. In the present study, a caecal ligation and puncture (CLP)-induced sepsis model was established to investigate the effect of β-catenin on sepsis-induced inflammatory lung injury and the corresponding underlying mechanisms. C57BL/6 mice were randomly divided into five groups, namely, the sham, CLP, β-catenin knockout (KO) + CLP, XAV-939 + CLP, and ICG-001 + CLP groups; the XAV-939 + CLP and ICG-001 + CLP groups were separately subjected to intraperitoneal injections of the β-catenin inhibitors XAV-939 and ICG-001 for 1 week preoperatively and 2 days postoperatively, respectively. Forty-eight hours after CLP, we measured β-catenin expression in lung tissues and evaluated mouse mortality, histopathological characteristics of hematoxylin and eosin (H&E)-stained lung tissues, serum cytokine (tumor necrosis factor [TNF]-α, interleukin [IL]-10, and IL-1β) levels, lung myeloperoxidase (MPO) activity, and the number of apoptotic cells in the lung tissues. Our results indicated that both the inhibition of β-catenin expression and blockage of β-catenin/CREB-binding protein (CBP) interactions by ICG-001 effectively decreased mouse mortality, alleviated pathological lung injury, and reduced the serum TNF-α, IL-10, and IL-1β levels, in addition to reducing the lung MPO activity and the number of apoptotic cells in lung tissues of the sepsis model mice. Therefore, it can be deduced that the β-catenin/CBP signaling axis participates in regulating sepsis-induced inflammatory lung injury.

Therapeutic Potential of Certain Terpenoids as Anticancer Agents: A Scoping Review

Cancer is a life-threatening disease and is considered to be among the leading causes of death worldwide. Chemoresistance, severe toxicity, relapse and metastasis are the major obstacles in cancer therapy. Therefore, introducing new therapeutic agents for cancer remains a priority to increase the range of effective treatments. Terpenoids, a large group of secondary metabolites, are derived from plant sources and are composed of several isoprene units. The high diversity of terpenoids has drawn attention to their potential anticancer and pharmacological activities. Some terpenoids exhibit an anticancer effect by triggering various stages of cancer progression, for example, suppressing the early stage of tumorigenesis via induction of cell cycle arrest, inhibiting cancer cell differentiation and activating apoptosis. At the late stage of cancer development, certain terpenoids are able to inhibit angiogenesis and metastasis via modulation of different intracellular signaling pathways. Significant progress in the identification of the mechanism of action and signaling pathways through which terpenoids exert their anticancer effects has been highlighted. Hence, in this review, the anticancer activities of twenty-five terpenoids are discussed in detail. In addition, this review provides insights on the current clinical trials and future directions towards the development of certain terpenoids as potential anticancer agents.

Lupeol synergizes with doxorubicin to induce anti-proliferative and apoptotic effects on breast cancer cells

PURPOSE

Anti-cancer and anti-migration effects of lupeol as a biological pentacyclic triterpenoid were investigated individually and in combination with Doxorubicin (DOX) on MCF-7 and MDA-MB-231 breast cancer cells and human foreskin fibroblasts.

METHODS

To uncover the anticancer effect of lupeol and the impact of its combination with DOX, cell viability and scratch assays and dual acridine-orange apoptotic staining were performed. Moreover, the expression of proapoptotic caspase-3 and metastasis-related MMP-9 at the mRNA and protein levels was analyzed using qPCR and western blot techniques.

RESULTS

Lupeol synergistically increased the anti-proliferative effect of DOX with IC50 values of 42.55, 62.24 and 65.9 μM on MCF-7, MDA-MB-231 and HFF cells, respectively. Lupeol reduced the cell migration and lowered the DOX-induced cell migration, significantly (p < 0.05). The number of apoptotic cells elevated significantly (p < 0.05) when cancer cells were treated with the combination of lupeol and DOX. Lupeol individually and in combination with DOX up-regulated the expression of caspase-3. The proposed combination therapy synergized (3-4 fold) the down-regulation of MMP-9 expression in MCF-7 and MDA-MB-231 cells.

CONCLUSION

Our results indicate that lupeol could be considered as an anticancer agent and anticancer adjuvant in breast cancer-therapy. The anticancer properties of lupeol attribute to its antiproliferative, antimigrative and apoptotic effects.

Investigation of Lupeol as Anti-Melanoma Agent: An In Vitro-In Ovo Perspective

Malignant melanoma (MM) represents the most life-threatening skin cancer worldwide, with a narrow and inefficient chemotherapeutic arsenal available in advanced disease stages. Lupeol (LUP) is a triterpenoid-type phytochemical possessing a broad spectrum of pharmacological properties, including a potent anticancer effect against several neoplasms (e.g., colorectal, lung, and liver). However, its potential as an anti-melanoma agent has been investigated to a lesser extent. The current study focused on exploring the impact of LUP against two human MM cell lines (A375 and RPMI-7951) in terms of cell viability, confluence, morphology, cytoskeletal distribution, nuclear aspect, and migration. Additionally, the in ovo antiangiogenic effect has been also examined. The in vitro results indicated concentration-dependent and selective cytotoxicity against both MM cell lines, with estimated IC₅₀ values of 66.59 ± 2.20 for A375, and 45.54 ± 1.48 for RPMI-7951, respectively, accompanied by a reduced cell confluence, apoptosis-specific nuclear features, reorganization of cytoskeletal components, and inhibited cell migration. In ovo, LUP interfered with the process of angiogenesis by reducing the formation of neovascularization. Despite the potential anti-melanoma effect illustrated in our in vitro-in ovo study, further investigations are required to elucidate the underlying LUP-induced effects in A375 and RPMI-7951 MM cells.

Compound Kushen Injection intervenes metabolic reprogramming and epithelial-mesenchymal transition of HCC via regulating β-catenin/c-Myc signaling

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most extensive and most deadly cancers worldwide. The invasion and metastasis characteristics of HCC dramatically affect the prognosis and survival of HCC patients. Compound Kushen Injection (CKI) is a GMP produced, proverbially applied traditional Chinese medicine formula in China to treat cancer-associated pains, and used as an adjunctive therapy for HCC. Until so far, whether CKI could suppress the metastasis of HCC through regulation of epithelial-mesenchymal transition or metabolic reprogramming is still ambiguous.

PURPOSE

In this study, the anti-metastasis effects of CKI were clarified and its pharmacological mechanisms were systematically explored.

METHODS

Cell invasion and cell adhesion assay were performed in SMMC-7721 cells to assess the anti-metastasis role of CKI, and the histopathological evaluation and biochemical detection were utilized in DEN-induced HCC rats to verify the anti-HCC effect of CKI. Serum and liver samples were analyzed with ¹H NMR metabolomics approach to screen the differential metabolites and further target quantification the content of key metabolites. Finally, western blotting and immunofluorescence assay were applied to verify the crucial signaling pathway involved in metabolites.

RESULTS

CKI markedly repressed the invasion and adhesion in SMMC-7721 cells and significantly improved the liver function of DEN-induced HCC rats. CKI significantly regulated the expression of epithelial-mesenchymal transition (EMT) markers (Vimentin and E-cadherin). Metabolomics results showed that CKI regulated the metabolic reprogramming of HCC by inhibiting the key metabolites (citrate and lactate) and enzymes (HK and PK) in glycolysis process. Importantly, we found that c-Myc mediates the inhibitory effect of CKI on glycolysis. We further demonstrated that CKI inhibits c-Myc expression through modulating Wnt/β-catenin pathway in SMMC-7721 cells and DEN-induced HCC rats. Furthermore, through activating Wnt/β-catenin pathway with LiCl, the inhibitory effects of CKI on HCC were diminished.

CONCLUSION

Together, this study reveals that CKI intervenes metabolic reprogramming and epithelial-mesenchymal transition of HCC via regulating β-catenin/c-Myc signaling pathway. Our research provides a new understanding of the mechanism of CKI against invasion and metastasis of HCC from the perspective of metabolic reprogramming.

Therapeutic Deep Eutectic Systems towards the Treatment of Tuberculosis and Colorectal Cancer: Opportunities and Challenges

What if a new technology based on therapeutic deep eutectic systems would disrupt the current treatment of major economic and socially burden diseases? The classical definition of eutectic systems is that they are the combination of two or more compounds that interact via hydrogen bonds, from which results a melting temperature depression in comparison with that of its individual components. Therapeutic deep eutectic systems are defined as eutectic systems in which at least one of the individual components is an active pharmaceutical ingredient, or a eutectic system in which the active pharmaceutical ingredient is dissolved. Current literature reports on tuberculosis have been mostly based on the most common anti-tuberculosis drugs prescribed. Using eutectic systems based on naturally occurring molecules known for their anti-microbial activity may also present a promising therapeutic strategy able to cope with the prevalence of Mycobacterium tuberculosis and prevent the appearance of multidrug resistance strains. With regards to colorectal cancer, literature has been unravelling combinations of terpenes with anti-inflammatory drugs that are selectively cytotoxic towards colorectal cancer cells and do not compromise the viability of normal intestinal cells. This technology could contribute to preventing tumor growth and metastasis while providing a patient compliance therapeutics, which will be crucial to the success of overcoming the challenges presented by cancers.

Babao Dan is a robust anti-tumor agent via inhibiting wnt/β-catenin activation and cancer cell stemness

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese Medicine (TCM) is being increasingly used worldwide due to its diverse efficacy and relatively low side effects. Babao Dan (BBD) is a well-known TCM formula that is currently used for the effective treatment of various cancers, however its underlying molecular mechanism remains unknown.

AIM OF THE STUDY

Tumor growth and tumor recurrence are characterized by two distinct populations of cells, namely the well-differentiated cancer cells composing the majority of tumor bulk, and cancer stem cells (CSCs) involved in tumor relapse, which are both strongly associated with excessive activation of Wnt/β-catenin signaling. Our study aims to elucidate the underlying molecular mechanisms associated with the anti-tumor proliferative effects of Babao Dan (BBD).

MATERIALS AND METHODS

We used a hepatoblastoma cell line HepG2 with stem cell-like traits that harbors a constitutively active mutant of β-catenin in order to study the anti-tumor ability of BBD via targeting Wnt/β-catenin signaling.

RESULTS

BBD robustly attenuated both the intrinsic and extrinsic activation of Wnt/β-catenin pathway in HepG2 hepatoblastoma cells, as well as Wnt target genes. Moreover, BBD significantly inhibited both the proliferation of well-differentiated cancer cells, as well as the stem-like property of CSCs as evidenced by EpCAM, a Wnt target gene and a novel marker of cancer cell stemness. In addition, mice administered with BBD using HepG2 cell line derived xenograft model had marked reductions in tumor size and weight, as well as significantly decreased expressions of Wnt target genes and cancer cell stemness.

CONCLUSION

Our findings elucidated the underlying molecular mechanisms associated with the robust anti-tumor effects of BBD via potent inhibition of Wnt/β-catenin signaling, and implicate its use in the clinical treatment of cancers.

Lupeol-Loaded Nanoparticles Enhance the Radiosensitivity of Hepatocellular Carcinoma by Inhibiting the Hyperactivation in Raf/Mitogen-Activated Protein Kinase and Phospatidylinositol-3 Kinase/mTOR Pathways

Radioresistance limits the effectiveness of radiotherapy for hepatocellular carcinoma. Raf and PI3K signaling cascades promote the formation of radioresistance in hepatocellular carcinoma (HCC). Lupeol has anticancer activity despite itspoor solubility in water and is toxic effect on normal tissue. In this study, nanoparticles (lupeol-NPs) were constructed using PEG-PLGA diblock copolymer vector, and results revealed that Lupeol-NPs reversed the radioresistance of hepatocellular carcinoma by inhibiting cellular proliferation and cell-cycle progression and promoting cellular apoptosis through blocking Raf/MAPK and PI3K/Akt signal transduction in radioresistant Huh-7^R cells. In vivo, Lupeol-NPs combined with radiotherapy inhibited the growth of radioresistant hepatocellular carcinoma in a xenogenic nude mouse model. Ki-67 proliferation index decreased significantly (p < 0.05). We conclude that Lupeol-NPs can increase the sensitivity of radioresistant hepatocellular carcinoma to radiotherapy through inhibiting the Raf and PI3K signal cascades.

The multidimensional role of the Wnt/β-catenin signaling pathway in human malignancies

Several signaling pathways have been identified as important for developmental processes. One of such important cascades is the Wnt/β-catenin signaling pathway, which can regulate various physiological processes such as embryonic development, tissue homeostasis, and tissue regeneration; while its dysregulation is implicated in several pathological conditions especially cancers. Interestingly, deregulation of the Wnt/β-catenin pathway has been reported to be closely associated with initiation, progression, metastasis, maintenance of cancer stem cells, and drug resistance in human malignancies. Moreover, several genetic and experimental models support the inhibition of the Wnt/β-catenin pathway to answer the key issues related to cancer development. The present review focuses on different regulators of Wnt pathway and how distinct mutations, deletion, and amplification in these regulators could possibly play an essential role in the development of several cancers such as colorectal, melanoma, breast, lung, and leukemia. Additionally, we also provide insights on diverse classes of inhibitors of the Wnt/β-catenin pathway, which are currently in preclinical and clinical trial against different cancers.

Targeting the crosstalk between canonical Wnt/β-catenin and inflammatory signaling cascades: A novel strategy for cancer prevention and therapy

Emerging scientific evidence indicates that inflammation is a critical component of tumor promotion and progression. Most cancers originate from sites of chronic irritation, infections and inflammation, underscoring that the tumor microenvironment is largely orchestrated by inflammatory cells and pro-inflammatory molecules. These inflammatory components are intimately involved in neoplastic processes which foster proliferation, survival, invasion, and migration, making inflammation the primary target for cancer prevention and treatment. The influence of inflammation and the immune system on the progression and development of cancer has recently gained immense interest. The Wnt/β-catenin signaling pathway, an evolutionarily conserved signaling strategy, has a critical role in regulating tissue development. It has been implicated as a major player in cancer development and progression with its regulatory role on inflammatory cascades. Many naturally-occurring and small synthetic molecules endowed with inherent anti-inflammatory properties inhibit this aberrant signaling pathway, making them a promising class of compounds in the fight against inflammatory cancers. This article analyzes available scientific evidence and suggests a crosslink between Wnt/β-catenin signaling and inflammatory pathways in inflammatory cancers, especially breast, gastrointestinal, endometrial, and ovarian cancer. We also highlight emerging experimental findings that numerous anti-inflammatory synthetic and natural compounds target the crosslink between Wnt/β-catenin pathway and inflammatory cascades to achieve cancer prevention and intervention. Current challenges, limitations, and future directions of research are also discussed.

Geoffroea decorticans fruit extracts inhibit the wnt/β-catenin pathway, a therapeutic target in cancer

Geoffroea decorticans (chañar) is commonly used for culinary and medicinal purposes in rural communities. The aim of this work was to chemically characterize three Geoffroea decorticans extracts and determine their capacity to modulate the wnt/β-catenin pathway. This signaling pathway plays a key role in embryonic development but its overactivation leads to cancer cell growth. Phytochemical analysis of extracts showed presence of major classes of phytochemicals. Gas chromatography-mass spectrometry results revealed the presence of acids, esters and furanic compounds. Using Xenopus embryos as in vivo model organisms, we found that the extracts modulated dorso-ventral axis formation and rescued hyperdorsalized phenotypes produced by LiCl treatment. In agreement with these findings, Geoffroea decorticans extracts decreased β-catenin levels and suppressed the expression of wnt target genes such as xnr3 and chordin, thus demonstrating an inhibitory regulation of the wnt/β-catenin signaling pathway. All these results support a new role for Geoffroea decorticans fruit derivatives with possible anti-carcinogenic actions.

Food-derived natural compounds in the management of chronic diseases via Wnt signaling pathway

Wnt signaling pathway is an evolutionarily conserved pathway that control embryonic development, adult tissue homeostasis, and pathological processes of organisms throughout life. However, dysregulation of the Wnt signaling is associated with the occurrence of chronic diseases. In comparison with the application of chemical drugs as traditional treatment for chronic diseases, dietary agents have unique advantages, such as less side effects, multiple targets, convenience in accessibility and higher acceptability in long-term intervention. In this review, we summarized current progress in manipulating the Wnt signaling using food components and its benefits in managing chronic diseases. The underlying mechanisms of bioactive food components in the management of the disease progression via the Wnt signaling was illustrated. Then, the review focused on the function of dietary pattern (which might act via combination of foods with multiple nutrients or food ingredients) on targeting Wnt signaling at multiple level. The potential caveats and challenges in developing new strategy via modulating Wnt-associated diseases with food-based agents and appropriate dietary pattern are also discussed in detail. This review shed light on the understanding of the regulatory effect of food bioactive components on chronic diseases management through the Wnt signaling, which can be expanded to other specific signaling pathway associated with disease.

Nature-derived compounds modulating Wnt/ -catenin pathway: a preventive and therapeutic opportunity in neoplastic diseases

The Wnt/β-catenin signaling is a conserved pathway that has a crucial role in embryonic and adult life. Dysregulation of the Wnt/β-catenin pathway has been associated with diseases including cancer, and components of the signaling have been proposed as innovative therapeutic targets, mainly for cancer therapy. The attention of the worldwide researchers paid to this issue is increasing, also in view of the therapeutic potential of these agents in diseases, such as Parkinson's disease (PD), for which no cure is existing today. Much evidence indicates that abnormal Wnt/β-catenin signaling is involved in tumor immunology and the targeting of Wnt/β-catenin pathway has been also proposed as an attractive strategy to potentiate cancer immunotherapy. During the last decade, several products, including naturally occurring dietary agents as well as a wide variety of products from plant sources, including curcumin, quercetin, berberin, and ginsenosides, have been identified as potent modulators of the Wnt/β-catenin signaling and have gained interest as promising candidates for the development of chemopreventive or therapeutic drugs for cancer. In this review we make an overview of the nature-derived compounds reported to have antitumor activity by modulating the Wnt/β-catenin signaling, also focusing on extraction methods, chemical features, and bio-activity assays used for the screening of these compounds.

Lupeol inhibits osteosarcoma progression by up-regulation of HMGA2 via regulating miR-212-3p

Background

Osteosarcoma (OS) is a common severe illness globally. Lupeol has been reported to participate in the pathophysiologic properties of various cancers, including OS. This study aimed to explore the effects of lupeol on proliferation, invasion, and apoptosis on OS cells and the underlying mechanism.

Methods

The cell viability of OS cells was determined by 3-(4, 5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. The expression levels of miR-212-3p and high-mobility group AT-hook 2 (HMGA2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) in OS cells. The cell apoptosis and invasion were detected by flow cytometry and transwell invasion assays, respectively. The functional target of miR-212-3p was predicted by online software and confirmed by luciferase reporter assay. The protein level of HMGA2 was measured by western blot analysis.

Results

Lupeol suppressed cell viability and invasion, and promoted apoptosis by upregulating the expression of miR-212-3p in OS cells. Knockdown of miR-212-3p restored the anti-tumor effect of lupeol. Interestingly, miR-212-3p directly targeted HMGA2 and suppressed its expression. Moreover, HMGA2 reversed the inhibited impact on viability and invasion, and the promoted effect on apoptosis induced by upregulation of miR-212-3p. Also, lupeol administration exerts its anti-tumor effect by overexpression of miR-212-3p to suppress the expression of HMGA2 in OS cells.

Conclusion

Lupeol inhibited OS progression by modulating the miR-212-3p/HMGA2 axis in vitro.

Engineering of HN3 increases the tumor targeting specificity of exosomes and upgrade the anti-tumor effect of sorafenib on HuH-7 cells

Safe, efficient and cancer cell targeted delivery of CRISPR/Cas9 is important to increase the effectiveness of available cancer treatments. Although cancer derived exosomes offer significant advantages, the fact that it carries cancer related/inducing signaling molecules impedes them from being used as a reliable drug delivery vehicle. In this study, we report that normal epithelial cell-derived exosomes engineered to have HN3 (HN3LC9-293exo), target tumor cells as efficiently as that of the cancer cell-derived exosomes (C9HuH-7exo). HN3LC9-293exo were quickly absorbed by the recipient cancer cell in vitro. Anchoring HN3 to the membrane of the exosomes using LAMP2, made HN3LC9-293exo to specifically enter the GPC3⁺ HuH-7 cancer cells than the GPC3⁻ LO2 cells in a co-culture model. Further, sgIQ 1.1 plasmids were loaded to exosomes and surprisingly, in combination with sorafenib, synergistic anti-proliferative and apoptotic effect of loaded HN3LC9-293exo was more than the loaded C9HuH-7exo. While cancer-derived exosomes might induce the drug resistance and tumor progression, normal HEK-293 cells-derived exosomes with modifications for precise cancer cell targeting like HN3LC9-293exo can act as better, safe and natural delivery systems to improve the efficacy of the cancer treatments.

WNT Signaling in Melanoma

WNT-signaling controls important cellular processes throughout embryonic development and adult life, so any deregulation of this signaling can result in a wide range of pathologies, including cancer. WNT-signaling is classified into two categories: β-catenin-dependent signaling (canonical pathway) and β-catenin-independent signaling (non-canonical pathway), the latter can be further divided into WNT/planar cell polarity (PCP) and calcium pathways. WNT ligands are considered as unique directional growth factors that contribute to both cell proliferation and polarity. Origin of cancer can be diverse and therefore tissue-specific differences can be found in WNT-signaling between cancers, including specific mutations contributing to cancer development. This review focuses on the role of the WNT-signaling pathway in melanoma. The current view on the role of WNT-signaling in cancer immunity as well as a short summary of WNT pathway-related drugs under investigation are also provided.

An update on the implications of cyclin D1 in melanomas

Cyclin D1 is a protein encoded by the CCND1 gene, located on 11q13 chromosome, which is a key component of the physiological regulation of the cell cycle. CCND1/cyclin D1 is upregulated in several types of human tumors including melanoma and is currently classified as an oncogene that promotes uncontrolled cell proliferation. Despite the demonstrated importance of CCND1/cyclin D1 as a central oncogene in several types of human tumors, its knowledge in melanoma is still limited. This review examines data published on upregulation of the CCND1 gene and cyclin D1 protein in the melanoma setting, focusing on the pathways and molecular mechanisms involved in the activation of the gene and on the clinical and therapeutic implications.

Chemosensitization of Therapy Resistant Tumors: Targeting Multiple Cell Signaling Pathways by Lupeol, A Pentacyclic Triterpene

Background:

The resistance of cancer cells to different therapies is one of the major stumbling blocks for successful cancer treatment. Various natural and pharmaceuticals drugs are unable to control drug-resistance cancer cell's growth. Also, chemotherapy and radiotherapy have several side effects and cannot apply to the patient in excess. In this context, chemosensitization to the therapy-resistant cells by non-toxic phytochemicals could be an excellent alternative to combat therapy-resistant cancers.

Objective:

To review the currently available literature on chemosensitization of therapy resistance cancers by Lupeol for clinically approved drugs through targeting different cell signaling pathways.

Methods:

We reviewed relevant published articles in PubMed and other search engines from 1999 to 2019 to write this manuscript. The key words used for the search were “Lupeol and Cancer”, “Lupeol and Chemosensitization”, “Lupeol and Cell Signaling Pathways”, “Cancer Stem Cells and Lupeol” etc. The published results on the chemosensitization of Lupeol were compared and discussed.

Results:

Lupeol chemosensitizes drug-resistant cancer cells for clinically approved drugs. Lupeol alone or in combination with approved drugs inhibits inflammation in different cancer cells through modulation of expression of IL-6, TNF-α, and IFN-γ. Lupeol, through altering the expression levels of BCL-2, BAX, Survivin, FAS, Caspases, and PI3K-AKT-mTOR signaling pathway, significantly induce cell deaths among therapy-resistant cells. Lupeol also modulates the molecules involved in cell cycle regulation such as Cyclins, CDKs, P53, P21, and PCNA in different cancer types.

Conclusion:

Lupeol chemosensitizes the therapy-resistant cancer cells for the treatment of various clinically approved drugs via modulating different signaling pathways responsible for chemoresistance cancer. Thus, Lupeol might be used as an adjuvant molecule along with clinically approved drugs to reduce the toxicity and increase the effectiveness.

Lupeol inhibits migration and invasion of colorectal cancer cells by suppressing RhoA-ROCK1 signaling pathway

Metastasis is the main cause of death in colorectal cancer (CRC) patients. However, current treatment options for CRC metastasis are very limited. Lupeol, a triterpene that is widely found in vegetables and fruits, has been reported to possess the cancer-preventive and anti-inflammatory functions. However, the roles of Lupeol in the migration and invasion of colorectal cancer remain unclear. Here, we evaluated the effect of Lupeol treatment on colorectal cancer cell lines, HCT116 and SW620, and delineated its underlying mechanisms. Our results showed that Lupeol induced a dose-dependent inhibition of HCT116 and SW620 cells viability, measured by CCK8 assay. Wound healing and Transwell migration and invasion assays revealed that Lupeol significantly suppressed the migration and invasion of CRC cells. Using laser confocal microscope, we observed that the pseudopods and protrusions of HCT116 and SW620 cells decreased and disrupted after treatment with Lupeol. In addition, the quantitative real-time PCR and Western blotting results showed that Lupeol downregulated the expression of RhoA and RhoC, and their downstream effectors ROCK1, Cofilin, p-MLC, and the associated regulatory protein Cyclin A2. Interestingly, the migration and invasion capacity of CRC cells was reduced after RhoA knockdown. And there were no additional changes in CRC cells with RhoA knockdown to treat with Lupeol. These findings demonstrate that Lupeol can suppress the migration and invasion of colorectal cancer cells by remodeling the actin cytoskeleton via RhoA-ROCK1 pathway inhibition, which may provide an effective anti-metastatic agent for CRC patients.

Oxidative stress and antioxidants in the pathophysiology of malignant melanoma

The high number of somatic mutations in the melanoma genome associated with cumulative ultra violet (UV) exposure has rendered it one of the most difficult of cancers to treat. With new treatment approaches based on targeted and immune therapies, drug resistance has appeared as a consistent problem. Redox biology, including reactive oxygen and nitrogen species (ROS and RNS), plays a central role in all aspects of melanoma pathophysiology, from initiation to progression and to metastatic cells. The involvement of melanin production and UV radiation in ROS/RNS generation has rendered the melanocytic lineage a unique system for studying redox biology. Overall, an elevated oxidative status has been associated with melanoma, thus much effort has been expended to prevent or treat melanoma using antioxidants which are expected to counteract oxidative stress. The consequence of this redox-rebalance seems to be two-fold: on the one hand, cells may behave less aggressively or even undergo apoptosis; on the other hand, cells may survive better after being disseminated into the circulating system or after drug treatment, thus resulting in metastasis promotion or further drug resistance. In this review we summarize the current understanding of redox signaling in melanoma at cellular and systemic levels and discuss the experimental and potential clinic use of antioxidants and new epigenetic redox modifiers.

Inhibition of the hedgehog pathway for the treatment of cancer using Itraconazole

Itraconazole (ITZ) is an anti-fungal drug that has been used in clinical practice for nearly 35 years. Recently, numerous experiments have shown that ITZ possesses anti-cancer properties. The Hedgehog (Hh) pathway plays a pivotal role in fundamental processes, including embryogenesis, structure, morphology and proliferation in various species. This pathway is typically silent in adult cells, and inappropriate activity is linked to various tumor types. The most important mechanism of ITZ in the treatment of cancer is inhibition of the Hh pathway through the inhibition of smoothened receptors (SMO), glioma-associated oncogene homologs (GLI), and their downstream targets. In this review, we discuss the mechanisms of ITZ in the treatment of cancer through inhibition of the Hh pathway, which includes anti-inflammation, prevention of tumor growth, induction of cell cycle arrest, induction of apoptosis and autophagy, prevention of angiogenesis, and drug resistance. We also discuss the clinical use of ITZ in many types of cancers. We hope this review will provide more information to support future studies on ITZ in the treatment of various cancers.

Pharmaceutical Topical Delivery of Poorly Soluble Polyphenols: Potential Role in Prevention and Treatment of Melanoma

Melanoma is regarded as the fifth and sixth most common cancer in men and women, respectively, and it is estimated that one person dies from melanoma every hour in the USA. Unfortunately, the treatment of melanoma is difficult because of its aggressive metastasis and resistance to treatment. The treatment of melanoma continues to be a challenging issue due to the limitations of available treatments such as a low response rate, severe adverse reactions, and significant toxicity. Natural polyphenols have attracted considerable attention from the scientific community due to their chemopreventive and chemotherapeutic efficacy. It has been suggested that poorly soluble polyphenols such as curcumin, resveratrol, quercetin, coumarin, and epigallocatechin-3-gallate may have significant benefits in the treatment of melanoma due to their antioxidant, anti-inflammatory, antiproliferative, and chemoprotective efficacies. The major obstacles for the use of polyphenolic compounds are low stability and poor bioavailability. Numerous nanoformulations, including solid lipid nanoparticles, polymeric nanoparticles, micelles, and liposomes, have been formulated to enhance the bioavailability and stability, as well as the therapeutic efficacy of polyphenols. This review will provide an overview of poorly soluble polyphenols that have been reported to have antimetastatic efficacy in melanomas.

Lupeol inhibits growth and migration in two human colorectal cancer cell lines by suppression of Wnt-β-catenin pathway

Background

Lupeol, a triterpene isolated from various herbal plants, possesses an anti-inflammatory function and has been proposed as a candidate for anticancer agents. The purpose of this research was to investigate the effect of lupeol on the viability, apoptosis, cell-cycle distribution, and migration of colorectal cancer cell lines and its molecular mechanism.

Methods

Lupeol was assessed for its anticancer effect using two human colorectal cancer cell lines: SW480 and HCT116. These cells were treated with lupeol, and their viability, apoptosis, migration, and cycle distribution were detected by CCK8, flow cytometry, and the transwell method. Quantitative PCR, Western blot, and immunofluorescence were applied to detect the expressions of CTNNB1, TCF4, cMYC, CCND1, CLDN1, and CCNA2.

Results

Lupeol suppressed cell viability and migration and induced cellular apoptosis of both cell lines, with increased p53 and decreased Bcl2 protein levels (P<0.05). Cell cycles of both lupeol-treated cell lines were arrested in the S phase (P<0.05). Quantitative PCR and Western blot analyses showed significantly reduced expressions of CTNNB1, TCF4, and downstream genes of the Wnt–β-catenin pathway, including the cell-cycle-regulated genes of cMYC and CCND1 of both cell lines upon lupeol treatment (P<0.05). mRNA and protein levels of CLDN1 decreased in HCT116 cells, plus the expression of CCNA2 mRNA and protein decreased in SW480 cells (P<0.05). Immunofluorescence analysis confirmed decreased expression of Wnt–β-catenin signaling.

Conclusion

Our findings indicate that lupeol effectively inhibits proliferation and migration and induces apoptosis and cell-cycle arrest of two colorectal cell lines by inactivation of the Wnt–β-catenin signaling pathway and downregulation of cMYC, CCND1, CCNA2, and CLDN1, thereby making it a promising anticancer candidate.

Itraconazole exerts its anti-melanoma effect by suppressing Hedgehog, Wnt, and PI3K/mTOR signaling pathways

Malignant melanoma is the deadliest form of all skin cancers. Itraconazole, a commonly used systemic antifungal drug, has been tested for its anti-tumor effects on basal cell carcinoma, prostate cancer, and non-small cell lung cancer. Whether itraconazole has any specific anti-tumor effect on melanoma remains unknown. However, the goal of this study is to investigate the effect of itraconazole on melanoma and to reveal some details of its underlying mechanism. In the in vivo xenograft mouse model, we find that itraconazole can inhibit melanoma growth and extend the survival of melanoma xenograft mice, compared to non-itraconazole-treated mice. Also, itraconazole can significantly inhibit cell proliferation, as demonstrated by Ki-67 staining in itraconazole-treated tumor tissues. In in vitro, we show that itraconazole inhibits the proliferation and colony formation of both SK-MEL-28 and A375 human melanoma cells. Moreover, we demonstrate that itraconazole significantly down-regulates Gli-1, Gli-2, Wnt3A, β-catenin and cyclin D1, while it up-regulates Gli-3 and Axin-1, indicating potent inhibitory effects of itraconazole on Hedgehog (Hh) and Wnt signaling pathways. Furthermore, itraconazole significantly suppresses the PI3K/mTOR signaling pathway – indicated by the down-regulated phosphorylation of p70S6K, 4E-BP1 and AKT – but has no effect on the phosphorylation of MEK or ERK. Our data suggest that itraconazole inhibits melanoma growth through an interacting regulatory network that includes Hh, Wnt, and PI3K/mTOR signaling pathways. These results suggest that this agent has several potent anti-melanoma features and may be useful in the synergesis of other anti-cancer drugs via blockage of the Hh, Wnt and PI3K/mTOR signaling pathways.

Differential effects of Wnt5a on the proliferation, differentiation and inflammatory response of keratinocytes

The predominant role of Wnt family member 5A (Wnt5a) is to induce non-canonical Wnt signalling pathways, including the Wnt‑Ca2+ and Wnt‑planar cell polarity pathways. Enhanced Wnt5a expression is involved in the formation of psoriatic plaques; however, its mechanistic role remains to be determined. In the present study, the effects of Wnt5a expression on HaCaT keratinocytes were investigated. HaCaT cells were cultured in medium supplemented with 0, 40 or 80 ng/ml Wnt5a for 24 h. Cell proliferation, the cell cycle, gene expression and inflammatory responses were investigated using Cell‑Counting Kit‑8 assays, flow cytometry analyses, reverse transcription‑quantitative polymerase chain reaction analyses and enzyme‑linked immunosorbent assays, respectively. Wnt5a treatment was revealed to suppress cell proliferation in HaCaT cells. Furthermore, Wnt5a was also demonstrated to increase the proportion of HaCaT cells arrested at the G2/M phase of the cell cycle, but reduce the proportion of HaCaT cells arrested at G0/G1 phase cells. In addition, the expression levels of the differentiation markers, including filaggrin, keratin 1 and keratin 10 were revealed to be downregulated in HaCaT cells. Expression of the canonical Wnt signalling genes (β‑catenin and cyclin D1) and proliferation markers, such as Ki‑67 and proliferating cell nuclear antigen in HaCaT cells were also revealed to be downregulated. However, the expression levels of inflammatory response markers (interferon‑γ, interleukin‑8 and interleukin‑17A) were revealed to be upregulated in HaCaT cells following Wnt5a treatment. These findings suggest that Wnt5a expression may be involved in the inhibition of cell differentiation and the induction of an inflammatory response in patients with psoriasis.

In vitro and in vivo anti-tumor activity of CoQ0 against melanoma cells: inhibition of metastasis and induction of cell-cycle arrest and apoptosis through modulation of Wnt/β-catenin signaling pathways

Coenzyme Q₀ (CoQ₀, 2,3-dimethoxy-5-methyl-1,4-benzoquinone), a novel quinone derivative, has been shown to modulate cellular redox balance. However, effect of this compound on melanoma remains unclear. This study examined the in vitro or in vivo anti-tumor, apoptosis, and anti-metastasis activities of CoQ₀ (0-20 μM) through inhibition of Wnt/β-catenin signaling pathway. CoQ₀ exhibits a significant cytotoxic effect on melanoma cell lines (B16F10, B16F1, and A2058), while causing little toxicity toward normal (HaCaT) cells. The suppression of β-catenin was seen with CoQ₀ administration accompanied by a decrease in the expression of Wnt/β-catenin transcriptional target c-myc, cyclin D1, and survivin through GSK3β-independent pathway. We found that CoQ₀ treatment caused G₁ cell-cycle arrest by reducing the levels of cyclin E and CDK4. Furthermore, CoQ₀ treatment induced apoptosis through caspase-9/-3 activation, PARP degradation, Bcl-2/Bax dysregulation, and p53 expression. Notably, non- or sub-cytotoxic concentrations of CoQ₀ markedly inhibited migration and invasion, accompanied by the down-regulation of MMP-2 and -9, and up-regulation of TIMP-1 and -2 expressions in highly metastatic B16F10 cells. Furthermore, the in vivo study results revealed that CoQ₀ treatment inhibited the tumor growth in B16F10 xenografted nude mice. Histological analysis and western blotting confirmed that CoQ₀ significantly decreased the xenografted tumor progression as demonstrated by induction of apoptosis, suppression of β-catenin, and inhibition of cell cycle-, apoptotic-, and metastatic-regulatory proteins. The data suggest that CoQ₀ unveils a novel mechanism by down-regulating Wnt/β-catenin pathways and could be used as a potential lead compound for melanoma chemotherapy.

Effects of microRNA-136 on melanoma cell proliferation, apoptosis, and epithelial-mesenchymal transition by targetting PMEL through the Wnt signaling pathway

The study aims to evaluate the effects of miR-136 on the proliferation, apoptosis, and epithelial–mesenchymal transition (EMT) of melanoma cells by targetting premelanosome protein (PMEL) through the Wnt signaling pathway. After establishment of melanoma mouse models, melanoma (model group) and normal tissues (normal group) were collected. Immunohistochemistry was performed to determine PMEL protein concentration. Mouse melanoma cells were assigned into control, blank, negative control (NC), miR-136 mimics, miR-136 inhibitors, siRNA-PMEL, and miR-136 inhibitors + siRNA-PMEL, LiC1 (Wnt signaling pathway activator), and siRNA-PMEL+ LiCl groups. MTT, Scratch test, Transwell assay, and flow cytometry were performed to measure cell proliferation, migration, invasion, and apoptosis. Quantitative real-time PCR (qRT-PCR) and Western blotting were performed to evaluate miR-136, PMEL, β-catenin, Wnt3a, Bcl-2, Bax, Caspase, E-cadherin, and N-cadherin expressions. PMEL is highly expressed in melanoma tissues. MiR-136, Bax, Caspase, and E-cadherin expressions decreased in the model group, whereas PMEL, β-catenin, Bcl-2, Wnt3a, and N-cadherin expressions increased. Bax, Caspase, and E-cadherin expressions increased in the miR-136 mimics and siRNA-PMEL groups, whereas the expressions decreased in the miR-136 inhibitors group and LiC1 group. PMEL, β-catenin, Bcl-2, Wnt3a, and N-cadherin expressions, cell proliferation, migration, and invasion decreased, and the apoptosis rate inceased in the miR-136 mimics and siRNA-PMEL groups; whereas the tendencies were opposite to those in the miR-136 inhibitors group and LiC1 group. In the siRNA-PMEL+ LiCl group, PMEL expression decreased. These findings indicated that overexpression of miR-136 inhibits melanoma cell EMT, proliferation, migration, invasion, and promotes apoptosis by targetting PMEL through down-regulation of the Wnt signaling pathway.

Lupeol and Its Role in Chronic Diseases

Lupeol belongs to pentacyclic lupane-type triterpenes and exhibits in edible vegetables, fruits and many plants. Many researches indicated that lupeol possesses many beneficial pharmacological activities including antioxidant, anti-inflammatory, anti-hyperglycemic, anti-dyslipidemic and anti-mutagenic effects. From various disease-targeted animal models, these reports indicated that lupeol has anti-diabetic, anti-asthma, anti-arthritic, cardioprotective, hepatoprotective, nephroprotective, neuroprotective and anticancer efficiency under various routes of administration such as topical, oral, subcutaneous, intraperitoneal and intravenous. It is worth mentioning that clinical trials of lupeol were performed to treat canine oral malignant melanoma and human moderate skin acne in Japan and Korea. The detailed mechanism of anti-inflammatory, anti-diabetic, hepatoprotective and anticancer activities was further reviewed from published papers. These evidence indicate that lupeol is a multi-target agent to exert diverse pharmacological potency with many potential targeting proteins such as α-glucosidase, α-amylase, protein tyrosine phosphatase 1B (PTP 1B) and TCA cycle enzymes and targeting pathway such as IL-1 receptor-associated kinase-mediated toll-like receptor 4 (IRAK-TLR4), Bcl-2 family, nuclear factor kappa B (NF-kB), phosphatidylinositol-3-kinase (PI3-K)/Akt and Wnt/β-catenin signaling pathways. This review also provides suggestion that lupeol might be a valuable and potential lead compound to develop as anti-inflammatory, anti-diabetic, hepatoprotective and anticancer drugs.

Potential therapeutic targets of epithelial-mesenchymal transition in melanoma

Melanoma is a cutaneous neoplastic growth of melanocytes with great potential to invade and metastasize, especially when not treated early and effectively. Epithelial-mesenchymal transition (EMT) is the process by which melanocytes lose their epithelial characteristics and acquire mesenchymal phenotypes. Mesenchymal protein expression increases the motility, invasiveness, and metastatic potential of melanoma. Many pathways play a role in promotion of mesenchymal protein expression including RAS/RAF/MEK/ERK, PI3K/AKT/mTOR, Wnt/β-catenin, and several others. Downstream effectors of these pathways induce expression of EMT transcription factors including Snail, Slug, Twist, and Zeb that promote repression of epithelial and induction of mesenchymal character. Emerging research has demonstrated that a variety of small molecule inhibitors as well as phytochemicals can influence the progression of EMT and may even reverse the process, inducing re-expression of epithelial markers. Phytochemicals are of particular interest as supplementary treatment options because of their relatively low toxicities and anti-EMT properties. Modulation of EMT signaling pathways using synthetic small molecules and phytochemicals is a potential therapeutic strategy for reducing the aggressive progression of metastatic melanoma. In this review, we discuss the emerging pathways and transcription factor targets that regulate EMT and evaluate potential synthetic small molecules and naturally occurring compounds that may reduce metastatic melanoma progression.

Antineoplastic Effects of Honokiol on Melanoma

Honokiol, a plant lignan has been shown to have antineoplastic effects against nonmelanoma skin cancer developments in mice. In this study, antineoplastic effects of honokiol were investigated in malignant melanoma models. In vitro effects of honokiol treatment on SKMEL-2 and UACC-62 melanoma cells were evaluated by measuring the cell viability, proliferation, apoptosis, cell cycle analysis, and expressions of various proteins associated with cell cycle progression and apoptosis. For the in vivo study, male nude mice inoculated with SKMEL-2 or UACC-62 cells received injections of sesame oil or honokiol for two to seven weeks. In vitro honokiol treatment caused significant decrease in cell viability, proliferation, cell cycle arrest, increased apoptosis, and modulation of apoptotic and cell cycle regulatory proteins. Honokiol caused an accumulation of cells in the G2/M phase of the cell cycle in SKMEL-2 and G0/G1 phase in UACC-62 cells. An elevated level of caspases and PARP were observed in both cell lines treated with honokiol. A decrease in the expression of various cell cycle regulatory proteins was also observed in honokiol treated cells. Honokiol caused a significant reduction of tumor growth in SKMEL-2 and UACC-62 melanoma xenografts. These findings suggest that honokiol is a good candidate for further studies as a possible treatment for malignant melanoma.

Capn4 promotes epithelial-mesenchymal transition in human melanoma cells through activation of the Wnt/β-catenin pathway

Melanoma, as one of the most highly metastatic types of cancer, is resistant to current treatment methods, including popular targeted molecular therapy. Consequently, it is essential to develop a deeper understanding of the mechanisms involved in melanoma progression so that alternative treatments may be identified. To date, accumulating evidence supports the use of calpains, including calpain small subunit 1 (also known as Capn4 or CAPNS1), which affect cancer progression through many pathways, such as epithelial‑mesenchymal transition (EMT), the Wnt/β-catenin (β-catenin) and the nuclear factor κB (NF-κB) signaling pathways. The EMT pathway is well known as one of the most important events in tumor metastasis. The present study observed cross-talk among the EMT, β-catenin and NF-κB pathways. To identify the underlying mechanisms of Capn4 activity in melanoma cells, we determined Capn4 expression by gene chip and immunohistochemistral analyses in melanoma tissues and cells in vitro. The extent of apoptosis as determined by TUNEL assay, DAPI staining, and cleaved-caspase-3 assay was increased in human melanoma cells in which Capn4 expression had been knocked down when compared with untreated cells. Transwell assays and xenograft tumorigenicity studies were also performed to assess the effects of Capn4 on migration and invasion in vitro and tumor growth in vivo, respectively. The levels of β-catenin, vimentin, E-cadherin and N-cadherin were altered in human melanoma cells as determined by western blot analysis assay. Our study demonstrated that Capn4 is an underlying target for melanoma treatment.

Lupeol enhances inhibitory effect of 5-fluorouracil on human gastric carcinoma cells

Lupeol, a dietary triterpene present in many fruits and medicinal plants, has been reported to possess many pharmacological properties including cancer-preventive and anti-cancer effects in vitro and in vivo. Here, we investigated the anti-cancer efficacy and adjuvant chemotherapy action of lupeol in gastric cancer (GC) cells (SGC7901 and BGC823) and explored the underlying mechanisms. Cells were treated with lupeol and/or 5-fluorouracil (5-Fu) and subjected to cell viability, colony formation, apoptosis, western blot, semiquantitative RT-PCR, and xenograft tumorigenicity assay. Our results showed that lupeol and 5-Fu inhibited the proliferation of SGC7901 and BGC823 cells, and combination treatment with lupeol and 5-Fu resulted in a combination index < 1, indicating a synergistic effect. Co-treatment with lupeol and 5-Fu induced apoptosis through up-regulating the expressions of Bax and p53 and down-regulating the expressions of survivin and Bcl-2. Furthermore, co-treatment displayed more efficient inhibition of tumor weight and volume on BGC823 xenograft mouse model than single-agent treatment with 5-Fu or lupeol. Taken together, our findings highlight that lupeol sensitizes GC to 5-Fu treatment, and combination treatment with lupeol and 5-Fu would be a promising therapeutic strategy for human GC treatment.

Possible Anticancer Mechanisms of Some Costus speciosus Active Ingredients Concerning Drug Discovery

Costus speciosus is native to South East Asia, especially found in India, Srilanka, Indonesia and Malaysia. C. speciosus have numerous therapeutic potentials against a wide variety of complains. The therapeutic properties of C. speciosus are attributed to the presence of various ingredients such as alkaloids, flavonoids, glycosides, phenols, saponins, sterols and sesquiterpenes. This review presented the past, present, and the future status of C. speciosus active ingredients to propose a future use as a potential anticancer agent. All possible up-regulation of cellular apoptotic molecules as p53, p21, p27, caspases, reactive oxygen species (ROS) generation and others attribute to the anticancer activity of C. speciosus along the down-regulation of anti-apoptotic agents such as Akt, Bcl2, NFKB, STAT3, JAK, MMPs, actin, surviving and vimentin. Eventually, we recommend further investigation of different C. speciosus extracts, using some active ingredients and evaluate the anticancer effect of these chemicals against different cancers.

Lupeol Induces Apoptosis and Cell Cycle Arrest of Human Osteosarcoma Cells Through PI3K/AKT/mTOR Pathway

Lupeol, a dietary triterpene present in many fruits and medicinal plants, has been reported to possess many pharmacological properties including anticancer effect in vitro and in vivo However, the activity of lupeol against osteosarcoma remains unclear. The present study is conducted to investigate the anticancer activity and the underlying mechanisms of lupeol on human osteosarcoma cells (MNNG/HOS and MG-63) in vitro and in vivo MNNG/HOS and MG-63 cells were treated by lupeol and subjected to methyl thiazolyl tetrazolium analysis, Hoechst staining, annexin V/propidium iodide double staining, cell cycle analysis, and Western blot analysis. In addition, MNNG/HOS xenograft tumors were established in female nude BALB/c mice, and lupeol was intravenously administered to evaluate the anticancer capacity in vivo Our results showed that lupeol induced apoptosis as well as cell cycle arrest in G0/G1 phase of MNNG/HOS and MG-63 cells in a dose-dependent manner in vitro Furthermore, the protein expression levels of phospho-phosphatidylinositol 3-kinase (p-PI3K), phospho-protein kinase B (p-AKT), p-p70S6K, and cyclin D1 were significantly downregulated, whereas the expression levels of p21 and p27 were upregulated. These protein interactions may play a pivotal role in the regulation of apoptosis and cell cycle arrest. More importantly, our in vivo studies showed that administration of lupeol decreased tumor growth in a dose-dependent manner and has no significant effect on the function of liver and kidney. Taken together, our findings indicated that lupeol can induce apoptosis as well as cell cycle arrest of human osteosarcoma cells through phosphatidylinositol 3-kinase/AKT/mammalian target of rapamycin pathway and might offer a promising new approach in the effective treatment of osteosarcoma.

Comparative study of anti-angiogenic activities of luteolin, lectin and lupeol biomolecules

BACKGROUND

Angiogenesis is a hallmark feature in the initiation, progression and growth of tumour. There are various factors for promotion of angiogenesis on one hand and on the other hand, biomolecules have been reported to inhibit cancer through anti-angiogenesis mechanism. Biomolecules, for instance, luteolin, lectin and lupeol are known to suppress cancer. This study aims to compare and evaluate the biomolecule(s) like luteolin, lupeol and lectin on CAM assay and HT-29 cell culture to understand the efficacy of these drugs.

METHOD

The biomolecules have been administered on CAM assay, HT-29 cell culture, cell migration assay. Furthermore, bioinformatics analysis of the identified targets of these biomolecules have been performed.

RESULT

Luteolin has been found to be better in inhibiting angiogenesis on CAM assay in comparison to lupeol and lectin. In line with this study when biomolecules was administered on cell migration assay via scratch assay method. We provided evidence that Luteolin was again found to be better in inhibiting HT-29 cell migration. In order to identify the target sites of luteolin for inhibition, we used software analysis for identifying the best molecular targets of luteolin. Using software analysis best target protein molecule of these biomolecules have been identified. VEGF was found to be one of the target of luteolin. Studies have found several critical point mutation in VEGF A, B and C. Hence docking analysis of all biomolecules with VEGFR have been performed. Multiple allignment result have shown that the receptors are conserved at the docking site.

CONCLUSION

Therefore, it can be concluded that luteolin is not only comparatively better in inhibiting blood vessel in CAM assay, HT-29 cell proliferation and cell migration assay rather the domain of VEGFR is conserved to be targeted by luteolin, lupeol and lectin.

Dietary phytochemicals alter epigenetic events and signaling pathways for inhibition of metastasis cascade: phytoblockers of metastasis cascade

Cancer metastasis is a multistep process in which a cancer cell spreads from the site of the primary lesion, passes through the circulatory system, and establishes a secondary tumor at a new nonadjacent organ or part. Inhibition of cancer progression by dietary phytochemicals (DPs) offers significant promise for reducing the incidence and mortality of cancer. Consumption of DPs in the diet has been linked to a decrease in the rate of metastatic cancer in a number of preclinical animal models and human epidemiological studies. DPs have been reported to modulate the numerous biological events including epigenetic events (noncoding micro-RNAs, histone modification, and DNA methylation) and multiple signaling transduction pathways (Wnt/β-catenin, Notch, Sonic hedgehog, COX-2, EGFR, MAPK-ERK, JAK-STAT, Akt/PI3K/mTOR, NF-κB, AP-1, etc.), which can play a key role in regulation of metastasis cascade. Extensive studies have also been performed to determine the molecular mechanisms underlying antimetastatic activity of DPs, with results indicating that these DPs have significant inhibitory activity at nearly every step of the metastatic cascade. DPs have anticancer effects by inducing apoptosis and by inhibiting cell growth, migration, invasion, and angiogenesis. Growing evidence has also shown that these natural agents potentiate the efficacy of chemotherapy and radiotherapy through the regulation of multiple signaling pathways. In this review, we discuss the variety of molecular mechanisms by which DPs regulate metastatic cascade and highlight the potentials of these DPs as promising therapeutic inhibitors of cancer.

A novel mechanism of hepatocellular carcinoma cell apoptosis induced by lupeol via Brain-Derived Neurotrophic Factor Inhibition and Glycogen Synthase Kinase 3 beta reactivation

Lupeol is a naturally available triterpenoid with selective anticancerous potential on various human cancer cells. The present study shows that lupeol can inhibit cell proliferation of hepatocellular carcinoma (HCC) HCCLM3 cells in a time- and dose-dependent manner, through caspase-3 dependent activation and Poly ADP-Ribose Polymerase (PARP) cleavage. Lupeol-induced cell death is associated with a marked decrease in the protein expression of Brain-Derived Neurotrophic Factor (BDNF) and ser-9-phosphoryltion of Glycogen Synthase Kinase 3 Beta (GSK-3β), with concomitant suppression of Akt1, phosphatidyl inositol 3-kinase (PI3K), β-catenin, c-Myc and Cyclin D1 mRNA expression. Suppressing overexpression of BDNF by lupeol results in decreased protein expression of p-Akt and PI3K (p110α), as well as reactivation of GSK-3β function in HepG2 cells. Lupeol treatment also inhibits LiCl-induced activation of Wnt signaling pathway and exerts the in vitro anti-invasive activity in Huh-7 cells. LiCl-triggered high expression of β-catenin, c-Myc and Cyclin D1 protein is reduced followed by lupeol exposure. The findings suggest a mechanistic link between caspase dependent pathway, BDNF secretion and Akt/PI3K/GSK-3β in HCC cells. These results indicate that lupeol can suppress HCC cell proliferation by inhibiting BDNF secretion and phosphorylation of GSK-3β(Ser-9), cooperated with blockade of Akt/PI3K and Wnt signaling pathway.

Targeting drivers of melanoma with synthetic small molecules and phytochemicals

Melanoma is the least common form of skin cancer, but it is responsible for the majority of skin cancer deaths. Traditional therapeutics and immunomodulatory agents have not shown much efficacy against metastatic melanoma. Agents that target the RAS/RAF/MEK/ERK (MAPK) signaling pathway - the BRAF inhibitors vemurafenib and dabrafenib, and the MEK1/2 inhibitor trametinib - have increased survival in patients with metastatic melanoma. Further, the combination of dabrafenib and trametinib has been shown to be superior to single agent therapy for the treatment of metastatic melanoma. However, resistance to these agents develops rapidly. Studies of additional agents and combinations targeting the MAPK, PI3K/AKT/mTOR (PI3K), c-kit, and other signaling pathways are currently underway. Furthermore, studies of phytochemicals have yielded promising results against proliferation, survival, invasion, and metastasis by targeting signaling pathways with established roles in melanomagenesis. The relatively low toxicities of phytochemicals make their adjuvant use an attractive treatment option. The need for improved efficacy of current melanoma treatments calls for further investigation of each of these strategies. In this review, we will discuss synthetic small molecule inhibitors, combined therapies and current progress in the development of phytochemical therapies.

Lupeol inhibits proliferation and induces apoptosis of human pancreatic cancer PCNA-1 cells through AKT/ERK pathways

Lupeol, a dietary triterpene, present in many fruits and medicinal plants, has been reported to possess many pharmacological properties including anti-cancer activities both in vitro and in vivo. However, the precise mechanism involved remains largely unknown. The present study is conducted to investigate the anti-cancer activity and the underlying mechanisms of lupeol on human pancreatic cancer proliferating cell nuclear antigen 1 (PCNA-1) cells in vitro and in vivo. Lupeol significantly inhibited the proliferation of the cells in dose- and time-dependent manners and induced apoptosis as well as cell cycle arrest in G0/G1 phase by upregulating P21 and P27 and downregulating cyclin D1. The expression of apoptosis-related proteins in cells was evaluated by western blot analysis, and we found that lupeol induced cell apoptosis by decreasing the levels of p-AKT and p-ERK. In addition, pretreatment with a specific PI3K/AKT activator (IGF-1) significantly neutralized the pro-apoptotic activity of lupeol in PCNA-1 cells, demonstrating the important role of AKT in this process. More importantly, our in vivo studies showed that administration of lupeol decreased tumor growth in a dose-dependent manner. Immunohistochemistry analysis demonstrated the downregulation of p-AKT and p-ERK in tumor tissues following lupeol treatment, consistent with the in vitro results. Therefore, these findings indicate that lupeol can inhibit cell proliferation and induce apoptosis as well as cell cycle arrest of PCNA-1 cells and might offer a therapeutic potential advantage for human pancreatic cancer chemoprevention or chemotherapy.

Negative regulation of signal transducer and activator of transcription-3 signalling cascade by lupeol inhibits growth and induces apoptosis in hepatocellular carcinoma cells

Background:

Constitutive activation of signal transducer and activator of transcription signalling 3 (STAT3) has been linked with survival, proliferation and angiogenesis in a wide variety of malignancies including hepatocellular carcinoma (HCC).

Methods:

We evaluated the effect of lupeol on STAT3 signalling cascade and its regulated functional responses in HCC cells.

Results:

Lupeol suppressed constitutive activation of STAT3 phosphorylation at tyrosine 705 residue effectively in a dose- and time-dependent manner. The phosphorylation of Janus-activated kinases (JAKs) 1 and 2 and Src was also suppressed by lupeol. Pervanadate treatment reversed the downregulation of phospho-STAT3 induced by lupeol, thereby indicating the involvement of a phosphatase. Indeed, we observed that treatment with lupeol increased the protein and mRNA levels of SHP-2, and silencing of SHP-2 abolished the inhibitory effects of lupeol on STAT3 activation. Treatment with lupeol also downregulated the expression of diverse STAT3-regulated genes and decreased the binding of STAT3 to VEGF promoter. Moreover, the proliferation of various HCC cells was significantly suppressed by lupeol, being associated with substantial induction of apoptosis. Depletion of SHP-2 reversed the observed antiproliferative and pro-apoptotic effects of lupeol.

Conclusions:

Lupeol exhibited its potential anticancer effects in HCC through the downregulation of STAT3-induced pro-survival signalling cascade.

Lupeol induces apoptosis and inhibits invasion in gallbladder carcinoma GBC-SD cells by suppression of EGFR/MMP-9 signaling pathway

The cytostatic drug from fruits and other plant derived products have acted as a chemotherapeutic agent used in treatment of a wide variety of cancers. Lupeol, a dietary triterpene, present in many fruits and medicinal plants, has been shown to possess many pharmacological properties including anti-cancer effect in both in vitro and in vivo assay systems. However, the cancer proliferative and invasive inhibitory effects and molecular mechanisms on gallbladder carcinoma GBC-SD cells have not been studied. In the present study, GBC-SD cells were treated by lupeol and subjected to methyl thiazolyl tetrazolium analysis, Hoechst 33342 staining, annexin V/propidium iodide double-staining, transwell chamber assay and Western blot analysis. In addition, GBC-SD xenograft tumors were established in male nude BALB/c mice, and lupeol was intravenously administered to evaluate the anti-cancer capacity in vivo. Our results showed that lupeol inhibited the proliferation, migration, invasion and induced apoptosis of GBC-SD cells in a dose-dependent manner in vitro. Furthermore, the expression of p-EGFR, p-AKT and MMP-9 levels were significantly down-regulated. These protein interactions may play a pivotal role in the regulation of apoptosis and invasion. More importantly, our in vivo studies showed that administration of lupeol decreased tumor growth in a dose-dependent manner. Immunohistochemistry analysis demonstrated the down-regulation of p-EGFR and MMP-9 in tumor tissues following lupeol treatment, consistent with the in vitro results. Taken together, our findings indicated that lupeol can induce apoptotic cell death and inhibit the migration as well as invasion of GBC-SD cells. The mechanism may be associated with the suppression of EGFR/MMP-9 signaling. These results might offer a therapeutic potential advantage for human gallbladder carcinoma chemoprevention or chemotherapy.

Wnt inhibitory factor-1 functions as a tumor suppressor through modulating Wnt/β-catenin signaling in neuroblastoma

Neuroblastoma is the most common extracranial solid tumor in childhood and is associated with serious morbidity and mortality. The effective treatment of neuroblastoma remains one of the major challenges in pediatric oncology. The Wnt signaling pathway has been shown to play a significant role in the pathogenesis of adult and pediatric tumors. WIF-1 has been identified as an important Wnt antagonist which inhibits Wnt/β-catenin signaling by directly binding to Wnt proteins. However, the expression and function of WIF-1 in neuroblastoma remains unknown. The present study showed that WIF-1 was downregulated with high level promoter methylation in neuroblastoma cells, and was significantly upregulated after exposure to demethylating agent. This finding suggests that downregulation of WIF-1 was associated with its promoter methylation in neuroblastoma. To further study the potential function of WIF-1 in neuroblastoma, we constructed a plasmid that over-expressed WIF-1 and transfected the plasmid into one neuroblastoma cell line SK-N-SH. We found that restoration of WIF-1 inhibited the growth and proliferation of neuroblastoma cells in vitro. Moreover, Wnt/β-catenin signaling activity and target genes expression were reduced by WIF-1 restoration. These results provide support that WIF-1 is downregulated and functions as a tumor suppressor by antagonizing Wnt/β-catenin signaling in neuroblastoma, suggesting a potential role as a therapeutic target in neuroblastoma.