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

Lupeol: A dietary and medicinal triterpene with therapeutic potential

Lupeol, a triterpene derived from various plants, has emerged as a potent dietary supplement with extensive therapeutic potential. This review offers a comprehensive examination of lupeol's applications across diverse health conditions. By meticulously analyzing current scientific literature, we have synthesized findings that underscore lupeol's impact on cancer, diabetes, gastrointestinal disorders, neurological diseases, dermatological conditions, nephrological issues, and cardiovascular health. The review delves into molecular studies that reveal lupeol's ability to modulate disease pathways and alleviate symptoms, positioning it as a promising therapeutic agent. Moreover, we discuss the potential role of lupeol in clinical practice and public health strategies, emphasizing its substantial benefits as a natural compound. This thorough analysis serves as a critical resource for researchers, providing insights into the multifaceted therapeutic properties of lupeol and its potential to significantly enhance health outcomes.

Effects of natural products on angiogenesis in melanoma

Melanoma is the most aggressive form of skin cancer and originates from genetic mutations in melanocytes. The disease is multifactorial, but its main cause is overexposure to UV radiation. Currently, available chemotherapy expresses little to no results, which may justify the extensive use of natural products to treat this cancer. In this study, we reviewed the inhibition of melanoma angiogenesis by natural products and its potential mechanisms using literature from PubMed, EMBASE, Web of Science, Ovid, ScienceDirect and China National Knowledge Infrastructure databases. According to summarizes 27 natural products including alkaloids, polyphenols, terpenoids, flavonoids, and steroids that effectively inhibit angiogenesis in melanoma. In addition to these there are 15 crude extracts that can be used as promising agents to inhibit angiogenesis, but their core components still deserve further investigation. There are current studies on melanoma angiogenesis involving oxidative stress, immune-inflammatory response, cell proliferation and migration and capillary formation. The above natural products can be involved in melanoma angiogenesis through core targets such as VE-cadherin, COX-2, iNOS, VEGF, bFGF, FGF2,MMP2,MMP9,IL-1β,IL-6 play a role in inhibiting melanoma angiogenesis. Effective excavation of natural products can not only clarify the mechanism of drug action and key targets, but also help to promote the preclinical research of natural products for melanoma treatment and further promote the development of new clinical drugs, which will bring the gospel to the vast number of patients who are deeply afflicted by melanoma.

Aspirin-Fisetin Combinatorial Treatment Exerts Cytotoxic and Anti-Migratory Activities in A375 Malignant Melanoma Cells

Background and Objectives: Malignant melanoma (MM) remains one of the most aggressive cancers worldwide, presenting a limited number of therapeutic options at present. Aspirin (ASA), a broadly used non-steroid anti-inflammatory medicine, has recently emerged as a candidate for repurposing in cancer management, due to its therapeutic potential in the treatment of several neoplasms which include MM. Fisetin (FIS) is a flavonoid phytoestrogen instilled with multispectral pharmacological activities, including a potent anti-melanoma property. The present study aimed to assess the potential improved anti-neoplastic effect resulting from the association of ASA and FIS for MM therapy. Materials and Methods: The study was conducted using the A375 cell line as an experimental model for MM. Cell viability was assessed via the MTT test. Cell morphology and confluence were evaluated using bright-field microscopy. The aspect of cell nuclei and tubulin fibers was observed through immunofluorescence staining. The irritant potential and the anti-angiogenic effect were determined on the chorioallantoic membrane of chicken fertilized eggs. Results: The main findings related herein demonstrated that the ASA 2.5 mM + FIS (5, 10, 15, and 20 µM) combination exerted a higher cytotoxicity in A375 MM cells compared to the individual compounds, which was outlined by the concentration-dependent and massive reduction in cell viability, loss of cell confluence, cell shrinkage and rounding, apoptotic-like nuclear features, constriction and disruption of tubulin filaments, increased apoptotic index, and suppressed migratory ability. ASA 2.5 mM + FIS 20 µM treatment lacked irritant potential on the chorioallantoic membrane and inhibited blood-vessel formation in ovo. Conclusion: These results stand as one of the first contributions presenting the anti-melanoma effect of the ASA + FIS combinatorial treatment.

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.

Lupeol and Paclitaxel cooperate in hindering hypoxia induced vasculogenic mimicry via suppression of HIF-1α-EphA2-Laminin-5γ2 network in human oral cancer

Vasculogenic mimicry (VM), defined as an endothelial cell independent alternative mechanism of blood and nutrient supply by dysregulated tumor cells, is associated with poor prognosis in oral squamous cell carcinoma (OSCC). Here we aim to investigate the underlying molecular mechanism of the synergistic effect of phytochemical Lupeol and standard microtubule inhibitor Paclitaxel in reversing the hypoxia induced VM formation in OSCC. The results demonstrated that the hypoxia induced upregulation of HIF-1α led to augmentation of signaling cascade associated with extracellular matrix remodeling and EMT phenotypes that are mechanistically linked to VM. Induction of HIF-1α altered the expression of EMT/CSC markers (E-Cadherin, Vimentin, Snail, Twist and CD133) and enhanced the ability of cell migration/invasion and spheroid formation. Subsequently, the targeted knockdown of HIF-1α by siRNA led to the perturbation of matrigel mediated tube formation as well as of Laminin-5γ2 expression with the down-regulation of VE-Cadherin, total and phosphorylated (S-897) EphA2, pERK1/2 and MMP2. We also observed that Lupeol in association with Paclitaxel resulted to apoptosis and the disruption of VM associated phenotypes in vitro. We further validated the impact of this novel interventional approach in a patient derived tumor explant culture model of oral malignancy. The ex vivo tumor model mimicked the in vitro anti-VM potential of Lupeol-Paclitaxel combination through down-regulating HIF-1α/EphA2/Laminin-5γ2 cascade. Together, our findings elucidated mechanistic underpinning of hypoxia induced Laminin-5γ2 driven VM formation highlighting that Lupeol-Paclitaxel combination may serve as novel therapeutic intervention in perturbation of VM in human OSCC.

Research Status and Hotspots of Anticancer Natural Products Based on the Patent Literature and Scientific Articles

Background: The patent literature contains a large amount of information on the internal state of current industrial technologies that are not available in other literature studies. Scientific articles are the direct achievements of theoretical research in this field and can reveal how current theories in basic research have developed. In this study, the progress and status of natural anticancer products in this field were summarized, and the research hotspots were explored through the analysis of the relevant patent literature and scientific articles. Methods: Patent data were retrieved from the incoPat patent retrieval database, and paper data were retrieved from the Web of Science core set and PubMed. GraphPad Prism 8, Microsoft Excel 2010, and CiteSpace 5.8.R3 were used to perform visual processing. The analyzed patent literature includes the patent applicant type, country (or region), and technical subject. The analyzed scientific article includes academic groups, subject areas, keyword clustering, and burst detection. Results: A total of 20,435 patent families and 38,746 articles were collected by 4 January 2022. At present, antitumor drugs derived from natural products mainly include 1) apoptosis inducers such as curcumin, gallic acid, resveratrol, Theranekron D6, and gaillardin; 2) topoisomerase inhibitors such as camptothecins, scaffold-hopped flavones, podophyllotoxin, oxocrebanine, and evodiamine derivatives; 3) telomerase inhibitors such as camptothecin and isoquinoline alkaloids of Chelidonium majus, amentoflavone, and emodin; 4) microtubule inhibitors such as kolaflavanone, tanshinone IIA analog, eugenol, and millepachine; 5) immunomodulators such as fucoidan, myricetin, bergapten, and atractylenolide I; 6) tumor microenvironment regulators such as beta-escin and icaritin; 7) multidrug resistance reversal agents such as berberine, quercetin, and dihydromyricetin; and 8) antiangiogenic and antimetastatic agents such as epigallocatechin-3-gallate, lupeol, ononin, and saikosaponin A. Conclusion: Anticancer natural product technology was introduced earlier, but the later development momentum was insufficient. In addition, scientific research activities are relatively closed, and technical exchanges need to be strengthened. Currently, the development of medicinal plants and the research on the anticancer mechanism of natural active products are still research hotspots, especially those related to immune checkpoints, essential oils, and metastatic cancer. Theories of traditional Chinese medicine (TCM), such as "restraining excessiveness to acquire harmony," "same treatment for different diseases," "Meridian induction theory," and "Fuzheng Quxie," have important guiding significance to the research of anticancer mechanisms and the development of new drugs and can provide new ideas for this process. Systematic Review Registration: [https://sourceforge.net/projects/citespace/], identifier [000755430500001].