Ursolic acid inhibits colorectal cancer angiogenesis through suppression of multiple signaling pathways

Natural products targeting tumour angiogenesis

Tumour angiogenesis is the formation of new blood vessels to support the growth of a tumour. This process is critical for tumour progression and metastasis, making it an attractive approach to cancer therapy. Natural products derived from plants, animals or microorganisms exert anti-angiogenic properties and can be used to inhibit tumour growth and progression. In this review, we comprehensively report on the current status of natural products against tumour angiogenesis from four perspectives until March 2023: (1) the role of pro-angiogenic factors and antiangiogenic factors in tumour angiogenesis; (2) the development of anti-tumour angiogenesis therapy (monoclonal antibodies, VEGFR-targeted small molecules and fusion proteins); (3) the summary of anti-angiogenic natural agents, including polyphenols, polysaccharides, alkaloids, terpenoids, saponins and their mechanisms of action, and (4) the future perspectives of anti-angiogenic natural products (bioavailability improvement, testing of dosage and side effects, combination use and discovery of unique natural-based compounds). Our review aims to better understand the potential of natural products for drug development in inhibiting tumour angiogenesis and further aid the effective transition of these outcomes into clinical trials. LINKED ARTICLES: This article is part of a themed issue Natural Products and Cancer: From Drug Discovery to Prevention and Therapy. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v182.10/issuetoc.

Ursolic acid induces apoptosis and disrupts host-parasite interactions in Theileria annulata-infected cells

This study explores the anti-proliferative and anti-parasitic properties of ursolic acid (UA) in Theileria annulata-infected bovine (TA) cells. Dose-response analyses determined an IC50 value of approximately 5 μg/mL for UA, demonstrating selective cytotoxicity toward infected cells with minimal impact on healthy cells. UA treatment induced pronounced morphological alterations and apoptosis in TA cells, as evidenced by light microscopy and a time-dependent increase in cell mortality. Notably, UA exhibited consistent efficacy against both buparvaquone (BPQ)-sensitive and BPQ-resistant TA cell lines, highlighting its broad-spectrum anti-parasitic potential. Mechanistic investigations revealed that UA triggers DNA damage, elevates reactive oxygen species (ROS) levels, disrupts mitochondrial function, and induces sub-G1 phase arrest, culminating in apoptosis primarily via the intrinsic pathway. Mass spectrometry-based proteomic profiling identified significant perturbations in host cell pathways, including DNA repair mechanisms, cell cycle regulation, and signaling networks, alongside direct interference with parasite metabolic processes. Western blot analysis further confirmed UA-mediated modulation of host cell signaling pathways and chromatin organization. Given the rising incidence of drug-resistant T. annulata strains, the development of novel therapeutic strategies is imperative. These findings highlight UA's multifaceted mechanism of action, targeting both parasitic and host cellular processes, and position it as a promising candidate for the treatment of bovine theileriosis.

Polyphenol Intake in Elderly Patients: A Novel Approach to Counteract Colorectal Cancer Risk?

Colorectal cancer (CRC) accounts for approximately 10% of all cancers worldwide with an incidence of approximately 60% in patients older than 70 years. In the elderly, the definition of a better therapeutic strategy depends on several factors including the patient's frailty and comorbidity status, life expectancy, and chemotherapy tolerance. In older patients, adverse drug reactions require a reduction in the dose of treatment, resulting in worse oncologic outcomes. In recent years, an increasing number of studies have focused on the potential effects of polyphenols on human health and their use in cancer therapy. In this comprehensive review, we searched the major databases and summarized experimental data of the most important polyphenols in the CRC chemoprevention, with a focus on the molecular mechanisms involved and the antitumor effects in the elderly population. In vitro and in vivo studies have shown that polyphenols exert chemopreventive activity by modulating cell signaling, resulting in the inhibition of cancer development or progression. However, the efficacy seen in experimental studies has not been confirmed in clinical trials, mainly due to their low bioavailability and non-toxic doses. Further research is needed to increase polyphenol bioavailability and reduce side effects in order to suggest their possible use to increase the efficacy of chemotherapeutic treatment.

Ursolic acid in colorectal cancer: mechanisms, current status, challenges, and future research directions

Colorectal cancer (CRC) ranks as the third most prevalent cancer globally, contributing to approximately 10% of all cancer cases and representing the second leading cause of cancer-related mortality worldwide. Ursolic acid (UA), a widely studied pentacyclic triterpenoid, has attracted substantial attention from researchers and clinicians due to its potential therapeutic effects against malignant tumors. Multiple studies have confirmed that UA inhibits tumor cell proliferation, induces differentiation and apoptosis, suppresses invasion, and impedes tumor angiogenesis via diverse mechanisms. However, research specifically addressing UA's anti-CRC effects remains limited, and systematic reviews of its underlying mechanisms in CRC are scarce. This study seeks to provide a comprehensive review of UA's mechanisms of action against CRC, offering valuable insights and references for researchers and clinicians.

Anti-angiogenic activity of polymeric nanoparticles loaded with ursolic acid

Ursolic acid (UA) is an abundant natural product and has shown great promise for treating diseases related to the appearance of new blood vessels. However, its clinical use is limited due to its low solubility in aqueous media, resulting in reduced bioavailability. The present study aimed to synthetize poly(lactic-co-glycolic acid) nanoparticles loaded with UA by nanoprecipitation method and to evaluate the toxicity and anti-angiogenic activity using the in vivo chorioallantoic model. The nanoparticles were obtained in the size range that varied from 103.0 to 169.3 nm, they presented a uniform distribution (polydispersity index <0.2), and a negatively charged surface, with an encapsulation efficiency close to 50%. The release profile of the developed nanoformulation showed an initial burst in the first 2 h and demonstrated no acute toxicity (irritation index <0.9). Moreover, the chorioallantoic assay showed a significant reduction in both geometrical and topological parameters compared to saline control (p < .05). In conclusion, the study revealed a quick and simple way to obtain poly(lactic-co-glycolic) acid nanoparticles, a drug delivery system to UA, which showed potential antiangiogenic action and can be used to treat diseases involving neovascularisation.

An Update on Pentacyclic Triterpenoids Ursolic and Oleanolic Acids and Related Derivatives as Anticancer Candidates

Cancer is a global health problem, with the incidence rate estimated to reach 40% of the population by 2030. Although there are currently several therapeutic methods, none of them guarantee complete healing. Plant-derived natural products show high therapeutic potential in the management of various types of cancer, with some of them already being used in current practice. Among different classes of phytocompounds, pentacyclic triterpenoids have been in the spotlight of research on this topic. Ursolic acid (UA) and its structural isomer, oleanolic acid (OA), represent compounds intensively studied and tested in vitro and in vivo for their anticancer and chemopreventive properties. Since natural compounds can rarely be used in practice as such due to their characteristic physico-chemical properties, to tackle this problem, their derivatization has been attempted, obtaining compounds with improved solubility, absorption, stability, effectiveness, and reduced toxicity. This review presents various UA and OA derivatives that have been synthesized and evaluated in recent studies for their anticancer potential. It can be observed that the most frequent structural transformations were carried out at the C-3, C-28, or both positions simultaneously. It has been demonstrated that conjugation with heterocycles or cinnamic acid, derivatization as hydrazide, or transforming OH groups into esters or amides increases anticancer efficacy.

Ursolic acid alleviates cancer cachexia by inhibiting STAT3 signaling pathways in C2C12 myotube and CT26 tumor-bearing mouse model

Cancer cachexia, a multi-organ disorder resulting from tumor and immune system interactions, prominently features muscle wasting and affects the survival of patients with cancer. Ursolic acid (UA) is known for its antioxidant, anti-inflammatory, and anticancer properties. However, its impact on cancer cachexia remains unexplored. This study aimed to assess the efficacy of UA in addressing muscle atrophy and organ dysfunction in cancer cachexia and reveal the mechanisms involved. UA dose-dependently ameliorated C2C12 myotube atrophy. Mechanistically, it inhibited the expression of muscle-specific RING finger containing protein 1 (MURF1) and the phosphorylation of signal transducer and activator of transcription 3 (STAT3), and upregulated the mRNA or protein levels of myogenic differentiation antigen and myogenin in cultured C2C12 myotubes treated with conditioned medium. In vivo, UA protected CT26 tumor-bearing mice against loss of body weight, as well as increased skeletal muscle and epididymal fat without affecting tumor growth. Additionally, UA increased food intake in CT26 tumor-bearing mice. The mRNA expression of tumor necrosis-α and interleukin 6 was significantly downregulated in the intestine, gastrocnemius, and heart tissues following 38 d UA administration. UA treatment reversed the levels of myocardial function indicators, including creatine kinase, creatine kinase-MB, lactate dehydrogenase, car-dial troponin T, and glutathione. Finally, UA treatment significantly inhibited the expression of MURF1, the phosphorylation of nuclear factor kappa-B p65, and STAT3 in the gastrocnemius muscle and heart tissues of cachexic mice. Our findings suggest that UA is a promising natural compound for developing dietary supplements for cancer cachexia therapy owing to its anti-catabolic effects.

Ursolic Acid's Alluring Journey: One Triterpenoid vs. Cancer Hallmarks

Cancer is a multifactorial disease characterized by various hallmarks, including uncontrolled cell growth, evasion of apoptosis, sustained angiogenesis, tissue invasion, and metastasis, among others. Traditional cancer therapies often target specific hallmarks, leading to limited efficacy and the development of resistance. Thus, there is a growing need for alternative strategies that can address multiple hallmarks concomitantly. Ursolic acid (UA), a naturally occurring pentacyclic triterpenoid, has recently emerged as a promising candidate for multitargeted cancer therapy. This review aims to summarize the current knowledge on the anticancer properties of UA, focusing on its ability to modulate various cancer hallmarks. The literature reveals that UA exhibits potent anticancer effects through diverse mechanisms, including the inhibition of cell proliferation, induction of apoptosis, suppression of angiogenesis, inhibition of metastasis, and modulation of the tumor microenvironment. Additionally, UA has demonstrated promising activity against different cancer types (e.g., breast, lung, prostate, colon, and liver) by targeting various cancer hallmarks. This review discusses the molecular targets and signaling pathways involved in the anticancer effects of UA. Notably, UA has been found to modulate key signaling pathways, such as PI3K/Akt, MAPK/ERK, NF-κB, and Wnt/β-catenin, which play crucial roles in cancer development and progression. Moreover, the ability of UA to destroy cancer cells through various mechanisms (e.g., apoptosis, autophagy, inhibiting cell growth, dysregulating cancer cell metabolism, etc.) contributes to its multitargeted effects on cancer hallmarks. Despite promising anticancer effects, this review acknowledges hurdles related to UA's low bioavailability, emphasizing the need for enhanced therapeutic strategies.

Pharmacological modulation of Sonic Hedgehog signaling pathways in Angiogenesis: A mechanistic perspective

The Sonic hedgehog (SHh) signaling pathway is an imperative operating network that helps in regulates the critical events during the development processes like multicellular embryo growth and patterning. Disruptions in SHh pathway regulation can have severe consequences, including congenital disabilities, stem cell renewal, tissue regeneration, and cancer/tumor growth. Activation of the SHh signal occurs when SHh binds to the receptor complex of Patch (Ptc)-mediated Smoothened (Smo) (Ptc-smo), initiating downstream signaling. This review explores how pharmacological modulation of the SHh pathway affects angiogenesis through canonical and non-canonical pathways. The canonical pathway for angiogenesis involves the activation of angiogenic cytokines such as fibroblast growth factor (FGF), vascular endothelial growth factor (VEGF), placental growth factor (PGF), hepatocyte growth factor (HGF), platelet-derived growth factor (PDGF), stromal cell-derived factor 1α, transforming growth factor-β1 (TGF-β1), and angiopoietins (Ang-1 and Ang-2), which facilitate the process of angiogenesis. The Non-canonical pathway includes indirect activation of certain pathways like iNOS/Netrin-1/PKC, RhoA/Rock, ERK/MAPK, PI3K/Akt, Wnt/β-catenin, Notch signaling pathway, and so on. This review will provide a better grasp of the mechanistic approach of SHh in mediating angiogenesis, which can aid in the suppression of certain cancer and tumor growths.

Ursolic Acid Inhibits the Growth of Gastric Cancer by Targeting KLF4/YAP1

Krüppel-like factor 4 (KLF4) is a zinc-finger transcription factor which has various mechanisms in different tumors. Ursolic acid (UA), a natural compound that exists in many herbs, is known to prevent tumor progression and has anticancer effects on many human cancers. The present study was to evaluate the antitumor effect of UA on gastric cancer (GC) through KLF4 and the Hippo pathway. Our data showed that UA inhibited the growth of GC in vivo and in vitro. UA treatment significantly increased the expression of KLF4 and decreased the expression of CTGF. The overexpression of KLF4 inhibited the proliferation and cell cycle of GC and decreased the expression of CTGF, whereas the knockdown of KLF4 attenuated the effects of UA. Furthermore, the inhibition of CTGF arrested tumor cells in G2/M which blocked proliferation progress. Confocal laser scanning and molecular simulation software MOE showed that KLF4 combined with YAP1 which may block the formation of the TEADs-YAP1 complex to interrupt the expression of CTGF and the downstream oncogenic process. In conclusion, UA can inhibit GC growth both in vivo and in vitro, and it activated KLF4 which may competitively bind with YAP1 against TEADs and block the oncogenic Hippo pathways.

Therapeutic potential and novel formulations of ursolic acid and its derivatives: an updated review

Plants produce biologically active metabolites that have been utilised to cure a variety of severe and persistent illnesses. There is a possibility that understanding how these bioactive molecules work would allow researchers to come up with better treatments for diseases including malignancy, cardiac disease and neurological disorders. A triterpene called ursolic acid (UA) is a pentacyclic prevalent triterpenoid found in fruits, leaves, herbs and blooms. The biological and chemical aspects of UA, as well as their presence, plant sources and biosynthesis, and traditional and newer technologies of extraction, are discussed in this review. Because of its biological function in the creation of new therapeutic techniques, UA is a feasible option for the evolution and medical management of a wide range of medical conditions, including cancer and other life threatening diseases. Despite this, the substance's poor solubility in aquatic environments makes it unsuitable for medicinal purposes. This hurdle was resolved in many different ways. The inclusion of UA into various pharmaceutical delivery approaches was found to be quite effective in this respect. This review also describes the properties of UA and its pharmacokinetics, as well as therapeutic applications of UA for cancer, inflammatory and cardiovascular diseases, in addition to its anti-diabetic, immunomodulatory, hepatoprotective and anti-microbial properties. Some of the recent findings related to novel nano-sized carriers as a delivery system for UA and the patents related to the applications of UA and its various derivatives are covered in this review. The analytical study of UA, oleanolic acid and other phytoconstituents by UV, HPLC, high-performance thin-layer chromatography and gas chromatography is also discussed. In the future, UA could be explored in vivo using various animal models and, in addition, the regulatory status regarding UA needs to be explored. © 2023 Society of Chemical Industry.

Ursolic Acid Alleviates Cancer Cachexia and Prevents Muscle Wasting via Activating SIRT1

Skeletal muscle wasting is the most remarkable phenotypic feature of cancer cachexia that increases the risk of morbidity and mortality. However, there are currently no effective drugs against cancer cachexia. Ursolic acid (UA) is a lipophilic pentacyclic triterpene that has been reported to alleviate muscle atrophy and reduce muscle decomposition in some disease models. This study aimed to explore the role and mechanisms of UA treatment in cancer cachexia. We found that UA attenuated Lewis lung carcinoma (LLC)-conditioned medium-induced C2C12 myotube atrophy and muscle wasting of LLC tumor-bearing mice. Moreover, UA dose-dependently activated SIRT1 and downregulated MuRF1 and Atrogin-1. Molecular docking results revealed a good binding effect on UA and SIRT1 protein. UA rescued vital features wasting without impacting tumor growth, suppressed the elevated spleen weight, and downregulated serum concentrations of inflammatory cytokines in vivo. The above phenomena can be attenuated by Ex-527, an inhibitor of SIRT1. Furthermore, UA remained protective against cancer cachexia in the advanced stage of tumor growth. The results revealed that UA exerts an anti-cachexia effect via activating SIRT1, thereby downregulating the phosphorylation levels of NF-κB and STAT3. UA might be a potential drug against cancer cachexia.

Ursolic Acid Suppresses Colorectal Cancer by Down-Regulation of Wnt/β-Catenin Signaling Pathway Activity

Overwhelming evidence points to an abnormally active Wnt/β-catenin signaling as a key player in colorectal cancer (CRC) pathogenesis. Ursolic acid (UA) is a pentacyclic triterpenoid that has been found in a broad variety of fruits, spices, and medicinal plants. UA has been shown to have potent bioactivity against a variety of cancers, including CRC, with the action mechanism obscure. Our study tried to learn more about the efficacy of UA on CRC and its functional mechanism amid the Wnt/β-catenin signaling cascade. We determined the efficacy of UA on CRC SW620 cells with respect to the proliferation, migration, clonality, apoptosis, cell cycle, and Wnt/β-catenin signaling cascade, with assessment of the effect of UA on normal colonic NCM460 cells. Also, the effects of UA on the tumor development, apoptosis, cell cycle, and Wnt/β-catenin signaling axis were evaluated after a subcutaneous SW620 xenograft tumor model was established in mice. In this work, we showed that UA drastically suppressed proliferation, migration, and clonality; induced apoptosis; and arrested the cell cycle at the G0/G1 phase of SW620 cells, without the influence on NCM460 cells, accompanied by weakened activity of the Wnt/β-catenin signaling pathway. Besides, UA markedly deterred the growth of the xenograft tumor, ameliorated pathological features, triggered apoptosis, and arrested the cell cycle in xenograft CRC tissue, by lessening the Wnt/β-catenin signaling cascade. Overall, UA may inhibit the malignant phenotype, induce apoptosis, and arrest the cell cycle of CRC, potentially by attenuating the Wnt/β-catenin signaling axis, providing insights into the mechanism for the potency of UA on CRC.

Ursolic acid: a pentacyclic triterpenoid that exhibits anticancer therapeutic potential by modulating multiple oncogenic targets

The world is currently facing a global challenge against neoplastic diseases. Chemotherapy, hormonal therapy, surgery, and radiation therapy are some approaches used to treat cancer. However, these treatments are frequently causing side effects in patients, such as multidrug resistance, fever, weakness, and allergy, among others side effects. As a result, current research has focused on phytochemical compounds isolated from plants to treat deadly cancers. Plants are excellent resources of bioactive molecules, and many natural molecules have exceptional anticancer properties. They produce diverse anticancer derivatives such as alkaloids, terpenoids, flavonoids, pigments, and tannins, which have powerful anticancer activities against various cancer cell lines and animal models. Because of their safety, eco-friendly, and cost-effective nature, research communities have recently focused on various phytochemical bioactive molecules. Ursolic acid (UA) and its derivative compounds have anti-inflammatory, anticancer, apoptosis induction, anti-carcinogenic, and anti-breast cancer proliferation properties. Ursolic acid (UA) can improve the clinical management of human cancer because it inhibits cancer cell viability and proliferation, preventing tumour angiogenesis and metastatic activity. Therefore, the present article focuses on numerous bioactivities of Ursolic acid (UA), which can inhibit cancer cell production, mechanism of action, and modulation of anticancer properties via regulating various cellular processes.

Ursolic acid: a natural modulator of signaling networks in different cancers

Incidence rate of cancer is estimated to increase by 40% in 2030. Furthermore, the development of resistance against currently available treatment strategies has contributed to the cancer-associated mortality. Scientists are now looking for the solutions that could help prevent the disease occurrence and could provide a pain-free treatment alternative for cancers. Therefore, efforts are now put to find a potent natural compound that could sever this purpose. Ursolic acid (UA), a triterpene acid, has potential to inhibit the tumor progression and induce sensitization to conventional treatment drugs has been documented. Though, UA is a hydrophobic compound therefore it is usually chemically modified to increase its bioavailability prior to administration. However, a thorough literature indicating its mechanism of action and limitations for its use at clinical level was not reviewed. Therefore, the current study was designed to highlight the potential mechanism of UA, its anti-cancer properties, and potential applications as therapeutic compound. This endeavour is a valuable contribution in understanding the hurdles preventing the translation of its potential at clinical level and provides foundations to design new studies that could help enhance its bioavailability and anti-cancer potential for various cancers.

Ursolic acid inhibits the activation of smoothened-independent non-canonical hedgehog pathway in colorectal cancer by suppressing AKT signaling cascade

It is being brought to light that smoothened (SMO)-independent non-canonical Hedgehog signaling is associated with the pathogenesis of various cancers. Ursolic acid (UA), a pentacyclic triterpenoid present in many medicinal herbs, manifests potent effectiveness against multiple malignancies including colorectal cancer (CRC). In our previous study, UA was found to protect against CRC in vitro by suppression of canonical Hedgehog signaling cascade. Here, the influence of UA on SMO-independent non-canonical Hedgehog signaling in CRC was investigated in the present study, which demonstrated that UA hampered the proliferation and migration, induced the apoptosis of HCT-116hSMO- cells with SMO gene knockdown, accompanied by the augmented expression of the suppressor of fused (SUFU), and lessened levels of MYC (c-Myc), glioma-associated oncogene (GLI1) and Sonic Hedgehog (SHH), and lowered phosphorylation of protein kinase B (PKB, AKT), suggesting that UA diminished non-canonical Hedgehog signal transduction in CRC. In HCT-116hSMO- xenograft tumor, UA ameliorated the symptoms, impeded the growth and caused the apoptosis of CRC, with heightened SUFU expression, and abated levels of MYC, GLI1, and SHH, and mitigated phosphorylation of AKT, indicating that UA down-regulated non-canonical Hedgehog signaling cascade in CRC. Taken together, UA may alleviate CRC by suppressing AKT signaling-dependent activation of SMO-independent non-canonical Hedgehog pathway.

Recent Advances Regarding the Molecular Mechanisms of Triterpenic Acids: A Review (Part I)

Triterpenic acids are phytocompounds with a widespread range of biological activities that have been the subject of numerous in vitro and in vivo studies. However, their underlying mechanisms of action in various pathologies are not completely elucidated. The current review aims to summarize the most recent literature, published in the last five years, regarding the mechanism of action of three triterpenic acids (asiatic acid, oleanolic acid, and ursolic acid), corelated with different biological activities such as anticancer, anti-inflammatory, antidiabetic, cardioprotective, neuroprotective, hepatoprotective, and antimicrobial. All three discussed compounds share several mechanisms of action, such as the targeted modulation of the PI3K/AKT, Nrf2, NF-kB, EMT, and JAK/STAT3 signaling pathways, while other mechanisms that proved to only be specific for a part of the triterpenic acids discussed, such as the modulation of Notch, Hippo, and MALAT1/miR-206/PTGS1 signaling pathway, were highlighted as well. This paper stands as the first part in our literature study on the topic, which will be followed by a second part focusing on other triterpenic acids of therapeutic value.

A New Approach to Inhibiting Triple-Negative Breast Cancer: In Vitro, Ex Vivo and In Vivo Antiangiogenic Effect of BthTx-II, a PLA2-Asp-49 from Bothrops jararacussu Venom

Phospholipases A2 (PLA2) represent a superfamily of enzymes widely distributed in living organisms, with a broad spectrum of pharmacological activities and therapeutic potential. Anti-angiogenic strategies have become one of the main tools in fighting cancer. In this sense, the present work reports the inhibition of tumor angiogenesis induced by Asp-49 BthTX-II using in vitro, ex vivo and in vivo approaches. We demonstrate that BthTx-II inhibited cell adhesion, proliferation, and migration of human umbilical vein endothelial cells (HUVEC), as well as caused a reduction in the levels of endothelial growth factor (VEGF) during in vitro angiogenesis assays. BthTx-II was also able to inhibit the sprouting angiogenic process, by the ex vivo germination assay of the aortic ring; in addition, this toxin inhibited the migration and proliferation of HUVEC in co-culture with triple-negative breast cancer cells (e.g., MDA-MB-231 cells). Finally, in vivo tumor suppression and anti-angiogenic activities were analyzed using MDA-MB-231 cells with Matrigel injected into the chorioallantoic membrane of chicken embryo (CAM) for 7 days treatment with BthTx-II, showing a considerable reduction in vessel caliber, on the size and weight of tumors. Together, these results suggest an important antiangiogenic and antitumor role for BthTx-II, as a potential prototype for the development of new tools and antitumor drugs in cancer therapy.

The possible role of ursolic acid in Covid-19: A real game changer

Ursolic acid (UA) is a pentacyclic terpenoid is usually found in the fruit peels and stem bark as secondary metabolites. UA has antiviral, antibacterial, and antiparasitic properties. UA has a wide spectrum of pharmacological activities against different infections. Because of the greatest antiviral and anti-inflammatory properties of UA, so it could be a plausible therapeutic herbal medicine in Covid-19 treatment. Covid-19 is a recent worldwide virulent disease pandemic due to severe acute respiratory coronavirus disease 2 (SARS-CoV-2). The pathogenesis of SARS-CoV-2 infection is related to the direct cytopathic effect and exaggerated immune response by which acute lung injury (ALI) and/or acute respiratory distress syndrome might be developed in critical cases. UA may inhibit main protease of SARS-CoV-2, and inhibits the interface flanked by SARS-CoV-2 viral proteins and its entry point commonly recognized as angiotensin converting enzyme 2 (ACE2). In addition, UA attenuates SARS-CoV-2-induced inflammatory reactions and oxidative stress. Therefore, UA could avert SARS-CoV-2 infection from causing ALI. This opinion proposed that UA might be a potential candidate therapy against Covid-19 and can mitigate post-Covid-19 complications such as lung fibrosis. In this regards, forthcoming studies are reasonable to substantiate the therapeutic role of UA in Covid-19. However, taken into account that Covid-19 is yet to be investigating for further evaluations, therefore, clinical trials are recommended regarding use and dose of UA in Covid-19 treatment, as well as secondary effects.

Antiangiogenic Phytochemicals Constituent of Diet as Promising Candidates for Chemoprevention of Cancer

Despite the extensive knowledge on cancer nature acquired over the last years, the high incidence of this disease evidences a need for new approaches that complement the clinical intervention of tumors. Interestingly, many types of cancer are closely related to dietary habits associated with the Western lifestyle, such as low fruit and vegetable intake. Recent advances around the old-conceived term of chemoprevention highlight the important role of phytochemicals as good candidates for the prevention or treatment of cancer. The potential to inhibit angiogenesis exhibited by many natural compounds constituent of plant foods makes them especially interesting for their use as chemopreventive agents. Here, we review the antitumoral potential, with a focus on the antiangiogenic effects, of phenolic and polyphenolic compounds, such as quercetin or myricetin; terpenoids, such as ursolic acid or kahweol; and anthraquinones from Aloe vera, in different in vitro and in vivo assays, and the available clinical data. Although clinical trials have failed to assess the preventive role of many of these compounds, encouraging preclinical data support the efficacy of phytochemicals constituent of diet in the prevention and treatment of cancer, but a deeper understanding of their mechanisms of action and better designed clinical trials are urgently needed.

Angioprevention of Urologic Cancers by Plant-Derived Foods

The number of cancer cases worldwide keeps growing unstoppably, despite the undeniable advances achieved by basic research and clinical practice. Urologic tumors, including some as prevalent as prostate, bladder or kidney tumors, are no exceptions to this rule. Moreover, the fact that many of these tumors are detected in early stages lengthens the duration of their treatment, with a significant increase in health care costs. In this scenario, prevention offers the most cost-effective long-term strategy for the global control of these diseases. Although specialized diets are not the only way to decrease the chances to develop cancer, epidemiological evidence support the role of certain plant-derived foods in the prevention of urologic cancer. In many cases, these plants are rich in antiangiogenic phytochemicals, which could be responsible for their protective or angiopreventive properties. Angiogenesis inhibition may contribute to slow down the progression of the tumor at very different stages and, for this reason, angiopreventive strategies could be implemented at different levels of chemoprevention, depending on the targeted population. In this review, epidemiological evidence supporting the role of certain plant-derived foods in urologic cancer prevention are presented, with particular emphasis on their content in bioactive phytochemicals that could be used in the angioprevention of cancer.

Role for Plant-Derived Antioxidants in Attenuating Cancer Cachexia

Cancer cachexia is the progressive muscle wasting and weakness experienced by many cancer patients. It can compromise the response to gold standard cancer therapies, impair functional capacity and reduce overall quality of life. Cancer cachexia accounts for nearly one-third of all cancer-related deaths and has no effective treatment. The pathogenesis of cancer cachexia and its progression is multifactorial and includes increased oxidative stress derived from both the tumor and the host immune response. Antioxidants have therapeutic potential to attenuate cancer-related muscle loss, with polyphenols, a group of plant-derived antioxidants, being the most widely investigated. This review describes the potential of these plant-derived antioxidants for treating cancer cachexia.

A Review of Phosphocreatine 3 Kinase δ Subtype (PI3Kδ) and Its Inhibitors in Malignancy

Most cancer deaths are caused by metastasis. The phosphocreatine 3-kinase (PI3K) family includes the I–III classes, with class I divided into 4 subtypes (α, β, γ, δ); and PI3K signaling participates in the regulatory processes of cell proliferation, differentiation, apoptosis, and glucose transport. Moreover, PI3Ks are modulators of cellular membrane lipids involved in signaling and trafficking events. The PI3Kdelta isoform (PI3Kδ), which is not only specifically expressed in hematopoietic cells, but also in different tumor cell lines, is expressed extensively. The increase in PI3Kδ activity is often associated with a variety of cancers. Currently, the strategy of tumor therapy based on PI3Kδ and its related signaling pathway is developing. Besides its established role in controlling functions in autoimmunity and inflammation, the role of PI3Kδ in tumor and metastasis is not clearly elucidated, with the effects of inhibiting PI3Kδ in several types of tumors also remaining unexplored. In addition, the specific inhibitor of PI3Kδ in tumor progression and metastasis and its underlying mechanism need to be further studied. The purpose of this review is to rationalize the existing functions and mechanisms of PI3Kδ in tumor metastasis and the relationship with hematopoietic cells in cancers as well cross-talking with miRNA, which provides a new theoretical basis and potential therapeutic target for the drug therapy of tumor metastasis.

Ursolic Acid and Related Analogues: Triterpenoids with Broad Health Benefits

Ursolic acid (UA) is a well-studied natural pentacyclic triterpenoid found in herbs, fruit and a number of traditional Chinese medicinal plants. UA has a broad range of biological activities and numerous potential health benefits. In this review, we summarize the current data on the bioavailability and pharmacokinetics of UA and review the literature on the biological activities of UA and its closest analogues in the context of inflammation, metabolic diseases, including liver and kidney diseases, obesity and diabetes, cardiovascular diseases, cancer, and neurological disorders. We end with a brief overview of UA’s main analogues with a special focus on a newly discovered naturally occurring analogue with intriguing biological properties and potential health benefits, 23-hydroxy ursolic acid.

Nanoformulations of Ursolic Acid: A Modern Natural Anticancer Molecule

Background: Ursolic acid (UA) is a natural pentacyclic triterpene derived from fruit, herb, and other plants. UA can act on molecular targets of various signaling pathways, inhibit the growth of cancer cells, promote cycle stagnation, and induce apoptosis, thereby exerting anticancer activity. However, its poor water-solubility, low intestinal mucosal absorption, and low bioavailability restrict its clinical application. In order to overcome these deficiencies, nanotechnology, has been applied to the pharmacological study of UA.

Objective: In this review, we focused on the absorption, distribution, and elimination pharmacokinetics of UA in vivo, as well as on the research progress in various UA nanoformulations, in the hope of providing reference information for the research on the anticancer activity of UA.

Methods: Relevant research articles on Pubmed and Web of Science in recent years were searched selectively by using the keywords and subheadings, and were summarized systematically.

Key finding: The improvement of the antitumor ability of the UA nanoformulations is mainly due to the improvement of the bioavailability and the enhancement of the targeting ability of the UA molecules. UA nanoformulations can even be combined with computational imaging technology for monitoring or diagnosis.

Conclusion: Currently, a variety of UA nanoformulations, such as micelles, liposomes, and nanoparticles, which can increase the solubility and bioactivity of UA, while promoting the accumulation of UA in tumor tissues, have been prepared. Although the research of UA in the nanofield has made great progress, there is still a long way to go before the clinical application of UA nanoformulations.

Preclinical Drug Discovery in Colorectal Cancer: A Focus on Natural Compounds

BACKGROUND

Colorectal cancer (CRC) is considered one of the most predominant and deadly cancer globally. Nowadays, the main clinical management for this cancer includes chemotherapy and surgery; however, these treatments result in the occurrence of drug resistance and severe side effects, and thus it is a crucial requirement to discover an alternative and potential therapy for CRC treatment. Numerous therapeutic cancers were initially recognized from natural metabolites utilized in traditional medicine, and several recent types of research have shown that many natural products own potential effects against CRC and may assist the action of chemotherapy for the treatment of CRC. It has been indicated that most patients are well tolerated by natural compounds without showing any toxicity signs even at high doses. Conventional chemotherapeutics interaction with natural medicinal compounds presents a new feature in cancer exploration and treatment. Most of the natural compounds overwhelm malignant cell propagation by apoptosis initiation of CRC cells and arresting of the cell cycle (especially at G, S, and G2/M phase) that result in inhibition of tumor growth.

OBJECTIVE

This mini-review aimed to focus on natural compounds (alkaloids, flavonoids, polysaccharides, polyphenols, terpenoids, lactones, quinones, etc.) that were identified to have anti- CRC activity in vitro on CRC cell lines and/or in vivo experiments on animal models.

CONCLUSION

Most of the studied active natural compounds possess anti-CRC activity via different mechanisms and pathways in vitro and in vivo that might be used as assistance by clinicians to support chemotherapy therapeutic strategy and treatment doses for cancer patients.

Anticancer activity of Nigerian medicinal plants: a review

Background

Cancer is currently the leading cause of death globally and the number of deaths from cancer is on the rise daily. Medicinal plants have been in continuous use over the years for the management of cancer, particularly, in most developing countries of the world including Nigeria. The use of synthetic drugs for the treatment of cancer is often accompanied by toxic side effects. Thus, the alternative use of readily available and inexpensive medicinal plants is the panacea to the toxic side effects associated with synthetic drugs.

Main body

The present review summarized the anticancer activity of 51 medicinal plants that are widespread in all regions of Nigeria. Furthermore, the proposed anticancer pharmacological actions as well as the anticancer bioactive compounds, the type of cancer cell inhibited, the plant parts responsible for the anticancer activity, and the nature of the extracts used for the studies were discussed in this review. The 51 Nigerian medicinal plants were reported to exhibit anticancer activities of the prostate, cervices, lung, skin, colon, esophagus, blood, ovary, central nervous system/brain, breast, stomach, pancreas, larynx, and kidney. The major classes of bioactive compounds indicated to be responsible for the anticancer activity include the polyphenols, flavonoids, alkaloids, saponins, triterpenes, tannins, and quinones. The major anticancer pharmacological actions of these bioactive compounds were antiproliferative, cytotoxic, cytostatic, antimetastatic, apoptotic, and antioxidative as well as provoked cell cycle arrest, inhibition of angiogenesis and reduction of cancer cell viability.

Conclusion

The Nigerian medicinal plants can be harnessed to provide for readily available and inexpensive anticancer drugs in the future because the plants reported in this review showed promising anticancer activity.

A review on the phytochemical and pharmacological properties of Hyptis suaveolens (L.) Poit

BACKGROUND

Plants are the repository of variable number of valuable secondary metabolites that bears pharmacognostic and pharmacological implications having potentiality to emerge as super drugs in future. In-vivo production of these metabolites is influenced by the biotic and abiotic stresses resulting in continuous accumulation of diverse phytochemicals and their derivatives that can be useful in designing and developing potential drugs for future. The aim of the present study is to review the existence of medicinally important secondary metabolites and possible pharmacological and pharmacognostic importance of under-explored weed plant species Hyptis suaveolens (L.) Poit., to explore the potentiality of the plant for developing and designing the drugs for future.

MAIN BODY OF THE ABSTRACT

Hyptis suaveolens belonging to family Lamiaceae is the rich source of medicinally important phytochemicals like essential oils, tannins, saponins, phenols, flavonoids, terpenoids, alkaloids, and sterols. One or many of these compounds have antioxidative, anti-inflammatory, antispasmodic, anti-septic, anti-cancer, anti-ulcer, antimicrobial, antibacterial, antiviral, antifungal, anti-diabetic, anti-fertility, diaphoretics, anticutaneous, anticatarrhal, antirheumatic, anti-ulcer, gastroprotective, immunomodulatory, analgesic, and antiviral activity.

SHORT CONCLUSION

Hyptis suaveolens contains unique terpenoid metabolites like suaveolic acid, suaveolol, methyl suaveolate, beta-sitosterol, ursolic acid, and phenolic compound like rosamarinic acid, methyl rosamarinate that have potentiality to substitute the traditional drugs as therapeutic agent against the resistant and newly emerged bacterial and viral pathogens. Pentacyclic triterpenoid, ursolic acid have been reported to have effective antiviral response against the SARS-CoV2 responsible for the present COVID-19 pandemic and HIV virus for which no effective vaccines are available till date. Ursolic acid has the ability to modulate the activity of main protease (Mpro) that is essential for processing of SARS-CoV2 replicase-transcriptase machinery needed for viral replication and particle assembly.

Chinese herbal medicine promote tissue differentiation in colorectal cancer by activating HSD11B2

BACKGROUND

Colorectal cancer is a common malignant tumor of the digestive tract. In recent years, the incidence rate has increased year by year and is showing a younger trend. The application of Chinese herbal medicine (CHM) is one of the important methods for the treatment of colorectal cancer. CHM refers to the main therapeutic drugs based on traditional Chinese medicine (TCM), which is still valued. Many effective anticancer small-molecule compounds are derived from CHMs, and their effective anticancer ingredients and targets must be clarified and to further understand the molecular mechanisms by which CHM affects cancer.

METHODS

We analyzed the ingredients in CHM that were found to be effective against colorectal cancer and constructed an interaction network among these ingredients and the target protein. By analyzing the number of connections in the network and their type of interaction, we identified the key target protein Corticosteroid 11-beta-dehydrogenase isozyme 2, the enzyme encoded by HSD11B2. Analyses of HSD11B2 expression, survival curve, and co-expressed genes helped clarify the correlation between HSD11B2 and colorectal cancer as well as its underlying molecular mechanism.

RESULTS

We determined that the anticancer ingredients contained in Sanguisorba officinalis, Patrinia scabiosaefolia, and Smilax china had more connections to the target proteins found in colorectal cancer. In the interaction network, eight small-molecule compounds had an activating effect on HSD11B2. The expression of the HSD11B2 was markedly decreased in colorectal cancer tissues and was positively correlated with the overall survival time of patients. In addition, co-expression analyses showed a close relationship between HSD11B2 and tissue-specific genes in colorectal tissues. The expression levels of HSD11B2 in well-, moderately, and poorly differentiated tissues progressively decreased.

CONCLUSION

The HSD11B2 protein was a key CHM target for treating colorectal cancer. The key role of CHM may lie in activating HSD11B2 and further promoting tissue differentiation in colorectal cancer.

Picroside II, an iridoid glycoside from Picrorhiza kurroa, suppresses tumor migration, invasion, and angiogenesis in vitro and in vivo

Cancer is one of the leading causes of death worldwide. The development of novel anti-cancer agents from natural products is a promising approach to reduce cancer mortality. In this study, we investigated the anti-metastatic and anti-angiogenic activities of picroside II (PII) in human breast cancer cells both in vitro and in vivo. Our results demonstrated that PII significantly inhibited the migration and invasion of MDA-MB-231 cancer cells. With the treatment of PII, the activity of matrix metalloproteinase 9 (MMP-9) in MDA-MB-231 cancer cells was significantly inhibited both in vitro and in vivo. Meanwhile, PII showed effective anti-metastatic activity in an experimental lung metastasis model. Interestingly, cluster of differentiation 31 (CD31), a marker of angiogenesis, was significantly downregulated in the PII-treated tumor samples, indicating the anti-angiogenic activity of PII. Furthermore, we demonstrated that PII significantly inhibited the migration, invasion, and tube formation of human umbilical vein endothelial cells (HUVECs). The inhibition of MMP-9 activity in PII-treated HUVECs was also demonstrated. Finally, the suppression of angiogenesis by PII in the chick embryo chorioallantoic membrane (CAM) was observed. In conclusion, our results demonstrated that PII effectively inhibited the metastasis and angiogenesis of cancer cells both in vitro and in vivo, and thus, might be a novel candidate for cancer therapy.

Ursolic acid suppresses the invasive potential of colorectal cancer cells by regulating the TGF-β1/ZEB1/miR-200c signaling pathway

Ursolic acid (UA) is a biologically active compound, commonly used in traditional Chinese medicine (TCM). It has been reported to exhibit strong anticancer properties against a variety of cancers. Our previous studies showed that UA promoted apoptosis in colorectal cancer (CRC) cells and inhibited cellular proliferation and angiogenesis. However, the effect and underlying molecular mechanism of UA in CRC progression remain unclear. In the present study, the role of UA in suppressing the migration and invasion of human colon cancer HCT116 and HCT-8 cells was investigated, using Transwell assays. In addition, to evaluate whether the anticancer properties of UA were mediated by the regulation of a double-negative feedback loop consisting of the transforming growth factor-β1 (TGF-β1)/zinc finger E-box-binding homeobox (ZEB1) pathway and microRNA (miR)-200a/b/c, reverse transcription-quantitative PCR and western blot analysis were performed. The results indicated that UA treatment significantly suppressed cellular growth, migration and invasion in HCT116 and HCT-8 cells in a dose-dependent manner. Furthermore, following UA treatment, several crucial mediators of the TGF-β1 signaling pathway, including TGF-β1, phosphorylated (p)-Smad2/3, p-focal adhesion kinase and ZEB1, were significantly downregulated in the HCT116 and HCT-8 cell lines compared with the control group. Furthermore, the ratio of N-cadherin/E-cadherin, two proteins directly downstream of the TGF-β1 signaling pathway, was found to be downregulated in UA treated CRC cells. Finally, UA significantly upregulated miR200a/b/c, with miR-200c exhibiting the highest increase in expression levels following UA treatment. Collectively, the present study suggested that inhibition of CRC cell invasion by UA occurred via regulation of the TGF-β1/ZEB1/miR-200c signaling network, which may be one of the mechanisms by which UA appears to be an effective therapeutic agent against colon cancer.

The Mediterranean Diet, a Rich Source of Angiopreventive Compounds in Cancer

Diet-based chemoprevention of cancer has emerged as an interesting approach to evade the disease or even target its early phases, reducing its incidence or slowing down tumor progression. In its basis in the essential role of angiogenesis for tumor growth and metastasis, angioprevention proposes the use of inhibitors of angiogenesis in cancer prevention. The anti-angiogenic potential exhibited by many natural compounds contained in many Mediterranean diet constituents makes this dietary pattern especially interesting as a source of chemopreventive agents, defined within the angioprevention strategy. In this review, we focus on natural bioactive compounds derived from the main foods included in the Mediterranean diet that display anti-angiogenic activity, as well as their possible use as angiopreventive agents.

Ursolic Acid Reverses the Chemoresistance of Breast Cancer Cells to Paclitaxel by Targeting MiRNA-149-5p/MyD88

Paclitaxel (PTX) is widely used as a front-line chemotherapy for breast cancer treatment. However, its clinical applications are limited by the development of chemoresistance. The objective of this study was to investigate the reversal effects of ursolic acid (UA) on PTX resistance and the possible mechanisms in breast cancer. The role of miRNA-149-5p/MyD88 in the regulation of PTX resistance was investigated by the transfection of breast cancer cells with MDA-MB-231 (231) and MDA-MB-231/PTX-resistance (231/PTX) with lentiviruses carrying the MyD88 gene, shRNA specific for MyD88, the miR-149-5p gene, and shRNA specific for miR-149-5p. The PTX sensitivity was assessed by a CCK-8 assay. qRT-PCR and Western blot analyses were used to detect changes in the mRNA and protein levels. Flow cytometry was used to measure the rate of cell apoptosis. A luciferase activity assay was used to detect the binding site of miR-149-5p on the 3'UTR of MyD88. 231/PTX cells were injected into the flanks of female athymic nude mice, and the mice were randomly divided into the five following groups: PBS, PTX (low), PTX (high), UA, and PTX+UA. Our data show that UA reversed the resistance of breast cancer 231/PTX cells to PTX in vitro and in vivo. UA treatment significantly increased the expression of miR-149-5p, which was lower in 231/PTX cells than in 231 cells. Furthermore, the overexpression of miR-149-5p increased the sensitivity of 231/PTX cells to PTX treatment, whereas the knockdown of the miR-149-5p gene attenuated the effects of UA on the regulation of PTX sensitivity. A luciferase assay demonstrated that miR-149-5p could directly regulate the transcriptional activity of MyD88, a known PTX-resistance gene, by targeting the 3'UTR of MyD88. Meanwhile, the downregulation of MyD88 through the overexpression of miR-149-5p or UA treatment inhibited the activation of the Akt signaling pathway in 231/PTX cells. Thus, our data indicate that UA can reverse PTX resistance by targeting the miRNA-149-5p/MyD88 axis in breast cancer cells.

A critical review on anti-angiogenic property of phytochemicals

Angiogenesis, a process involved in neovascularization, has been found to be associated with several metabolic diseases like cancer, retinopathy etc. Thus, currently, the focus on anti-angiogenic therapy for treatment and prevention of diseases has gained significant attention. Currently available Food and Drug Administration (FDA) approved drugs are targeting either vascular endothelial growth factor or it's receptor, but in the long term, these approaches were shown to cause several side effects and the chances of developing resistance to these drugs is also high. Therefore, identification of safe and cost-effective anti-angiogenic molecules is highly imperative. Over the past decades, dietary based natural compounds have been studied for their anti-angiogenic potential which provided avenues in improving the angiogenesis based therapy. In this review, major emphasis is given to the molecular mechanism behind anti-angiogenic effect of natural compounds from dietary sources.

Ursolic acid: An overview on its cytotoxic activities against breast and colorectal cancer cells

Ursolic acid (UA) is a pentacyclic triterpene of the ursane type. As a common chemical constituent among species of the family Lamiaceae, UA possesses a broad spectrum of pharmacological properties. This overview focuses on the anticancer properties of UA against breast cancer (BC) and colorectal cancer (CRC) that are most common among women and men, respectively. In vitro studies have shown that UA inhibited the growth of BC and CRC cell lines through various molecular targets and signaling pathways. There are several in vivo studies on the cytotoxic activity of UA against BC and CRC. UA also inhibits the growth of other types of cancer. Studies on structural modifications of UA have shown that the -OH groups at C3 and at C28 are critical factors influencing the cytotoxic activity of UA and its derivatives. Some needs for future research are suggested. Sources of information were from ScienceDirect, Google Scholar and PubMed.

Cis-3-O-p-hydroxycinnamoyl Ursolic Acid Induced ROS-Dependent p53-Mediated Mitochondrial Apoptosis in Oral Cancer Cells

Cis-3-O-p-hydroxycinnamoyl ursolic acid (HCUA), a triterpenoid compound, was purified from Elaeagnus oldhamii Maxim. This traditional medicinal plant has been used for treating rheumatoid arthritis and lung disorders as well as for its anti-inflammation and anticancer activities. This study aimed to investigate the anti-proliferative and apoptotic-inducing activities of HCUA in oral cancer cells. HCUA exhibited anti-proliferative activity in oral cancer cell lines (Ca9-22 and SAS cells), but not in normal oral fibroblasts. The inhibitory concentration of HCUA that resulted in 50% viability was 24.0 µM and 17.8 µM for Ca9-22 and SAS cells, respectively. Moreover, HCUA increased the number of cells in the sub-G1 arrest phase and apoptosis in a concentration-dependent manner in both oral cancer cell lines, but not in normal oral fibroblasts. Importantly, HCUA induced p53-mediated transcriptional regulation of pro-apoptotic proteins (Bax, Bak, Bim, Noxa, and PUMA), which are associated with mitochondrial apoptosis in oral cancer cells via the loss of mitochondrial membrane potential. HCUA triggered the production of intracellular reactive oxygen species (ROS) that was ascertained to be involved in HCUA-induced apoptosis by the ROS inhibitors YCG063 and N-acetyl-L-cysteine. As a result, HCUA had potential antitumor activity to oral cancer cells through eliciting ROS-dependent and p53-mediated mitochondrial apoptosis. Overall, HCUA could be applicable for the development of anticancer agents against human oral cancer.

Dietary phytochemicals in colorectal cancer prevention and treatment: A focus on the molecular mechanisms involved

Worldwide, colorectal cancer (CRC) remains a major cancer type and leading cause of death. Unfortunately, current medical treatments are not sufficient due to lack of effective therapy, adverse side effects, chemoresistance and disease recurrence. In recent decades, epidemiologic observations have highlighted the association between the ingestion of several phytochemical-enriched foods and nutrients and the lower risk of CRC. According to preclinical studies, dietary phytochemicals exert chemopreventive effects on CRC by regulating different markers and signaling pathways; additionally, the gut microbiota plays a role as vital effector in CRC onset and progression, therefore, any dietary alterations in it may affect CRC occurrence. A high number of studies have displayed a key role of growth factors and their signaling pathways in the pathogenesis of CRC. Indeed, the efficiency of dietary phytochemicals to modulate carcinogenic processes through the alteration of different molecular targets, such as Wnt/β-catenin, PI3K/Akt/mTOR, MAPK (p38, JNK and Erk1/2), EGFR/Kras/Braf, TGF-β/Smad2/3, STAT1-STAT3, NF-кB, Nrf2 and cyclin-CDK complexes, has been proven, whereby many of these targets also represent the backbone of modern drug discovery programs. Furthermore, epigenetic analysis showed modified or reversed aberrant epigenetic changes exerted by dietary phytochemicals that led to possible CRC prevention or treatment. Therefore, our aim is to discuss the effects of some common dietary phytochemicals that might be useful in CRC as preventive or therapeutic agents. This review will provide new guidance for research, in order to identify the most studied phytochemicals, their occurrence in foods and to evaluate the therapeutic potential of dietary phytochemicals for the prevention or treatment of CRC by targeting several genes and signaling pathways, as well as epigenetic modifications. In addition, the results obtained by recent investigations aimed at improving the production of these phytochemicals in genetically modified plants have been reported. Overall, clinical data on phytochemicals against CRC are still not sufficient and therefore the preventive impacts of dietary phytochemicals on CRC development deserve further research so as to provide additional insights for human prospective studies.

Ursolic and Oleanolic Acids as Potential Anticancer Agents Acting in the Gastrointestinal Tract

Background:

Cancer is one of the main causes of death worldwide. Contemporary therapies, including chemo- and radiotherapy, are burdened with severe side effects. Thus, there exists an urgent need to develop therapies that would be less devastating to the patient’s body. Such novel approaches can be based on the anti-tumorigenic activity of particular compounds or may involve sensitizing cells to chemotherapy and radiotherapy or reducing the side-effects of regular treatment.

Objective:

Natural-derived compounds are becoming more and more popular in cancer research. Examples of such substances are Ursolic Acid (UA) and Oleanolic Acid (OA), plant-derived pentacyclic triterpenoids which possess numerous beneficial properties, including anti-tumorigenic activity.

Results:

In recent years, ursolic and oleanolic acids have been demonstrated to exert a range of anticancer effects on various types of tumors. These compounds inhibit the viability and proliferation of cancer cells, prevent their migration and metastasis and induce their apoptosis. Both in vitro and in vivo studies indicate that UA and OA are promising anti-cancer agents that can prevent carcinogenesis at each step. Furthermore, cancers at all stages are susceptible to the activity of these compounds. </P><P> Neoplasms that are formed in the gastrointestinal tract, i.e. gastric, colorectal, pancreatic, and liver cancers, are among the most common and most lethal malignancies. Their localization in the digestive system, however, facilitates the action of orally-administered (potential) anti-cancer agents, making chemopreventive drugs more accessible.

Targeting VEGF/VEGFRs Pathway in the Antiangiogenic Treatment of Human Cancers by Traditional Chinese Medicine

Bearing in mind the doctrine of tumor angiogenesis hypothesized by Folkman several decades ago, the fundamental strategy for alleviating numerous cancer indications may be the strengthening application of notable antiangiogenic therapies to inhibit metastasis-related tumor growth. Under physiological conditions, vascular sprouting is a relatively infrequent event unless when specifically stimulated by pathogenic factors that contribute to the accumulation of angiogenic activators such as the vascular endothelial growth factor (VEGF) family and basic fibroblast growth factor (bFGF). Since VEGFs have been identified as the principal cytokine to initiate angiogenesis in tumor growth, synthetic VEGF-targeting medicines containing bevacizumab and sorafenib have been extensively used, but prominent side effects have concomitantly emerged. Traditional Chinese medicines (TCM)-derived agents with distinctive safety profiles have shown their multitarget curative potential by impairing angiogenic stimulatory signaling pathways directly or eliciting synergistically therapeutic effects with anti-angiogenic drugs mainly targeting VEGF-dependent pathways. This review aims to summarize ( a) the up-to-date understanding of the role of VEGF/VEGFR in correlation with proangiogenic mechanisms in various tissues and cells; ( b) the elaboration of antitumor angiogenesis mechanisms of 4 representative TCMs, including Salvia miltiorrhiza, Curcuma longa, ginsenosides, and Scutellaria baicalensis; and ( c) circumstantial clarification of TCM-driven therapeutic actions of suppressing tumor angiogenesis by targeting VEGF/VEGFRs pathway in recent years, based on network pharmacology.

Recent progress in natural dietary non-phenolic bioactives on cancers metastasis

From several decades ago to now, cancer continues to be the leading cause of death worldwide, and metastasis is the major cause of cancer-related deaths. For health benefits, there is a great desire to use non-chemical therapy such as nutraceutical supplementation to prevent pathology development. Over 10,000 different natural bioactives or phytochemicals have been known that possessing potential preventive or supplementary effects for various diseases including cancer. Previously, the in vitro and in vivo anti-invasive and anti-metastatic activities of phenolic acids, monophenol, polyphenol and their derivatives and flavonoids and their derivatives have been reviewed. However, a vast number of natural dietary compounds other than phenolics have been demonstrated to potentially possess the ability to inhibit the invasion and metastasis of various cancers. In this review, we summarize the studies in recent decade on in vitro and in vivo effects and molecular mechanisms of natural bioactives, excluding the phenolics in food, in cancer invasion and metastasis. By combining this review of non-phenolics with the previous phenolics reviews, the puzzle for the contribution of natural dietary bioactives on cancer invasive or/and metastatic progress will be almost complete and more clear.

Long-term electroacupuncture stimulation prevents osteoporosis in ovariectomised osteopaenic rats through multiple signalling pathways

BACKGROUND

The pathogenic mechanisms of postmenopausal osteoporosis (PMOP) development are complex and are related to multiple cellular signalling transduction pathways. The aim of this study was to compare the effects of electroacupuncture (EA) at GV4/GV6 versus BL20/BL23 on the bones in ovariectomised (OVX) rats to explore the pathways that mediate the effects of EA on bone.

METHODS

Forty female Sprague-Dawley rats were allocated to one of four groups (n=10 rats each) that received sham surgery (Sham group), OVX surgery only (OVX group), OVX surgery plus EA at GV4/GV6 (GV group) and OVX surgery plus EA at BL20/BL23 (BL group). Bone turnover markers osteocalcin (OC) and tartrate-resistant acid phosphatase 5b (TRACP 5b) were measured in serum, and bone mineral density (BMD) of the lumbar vertebrae and histomorphology of the femur were evaluated. Moreover, the expression of osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) was detected by ELISA. The expression of lipoprotein receptor-related protein (LRP) 5, β-catenin, runt-related transcription factor (Runx) 2 involving Wnt/β-catenin signalling and p38, c-Jun N-terminal kinase (JNK) and extracellular regulated protein kinases 1/2 involving mitogen-activated protein kinase signalling were determined by Western blotting.

RESULTS

The two EA-treated groups demonstrated increased levels of OC and the BMD of lumbar vertebrae, decreased levels of TRACP 5b and improved bone microstructure in the femur, compared with the untreated OVX group (P<0.05). Histomorphology analysis showed that EA treatment significantly increased the values of the trabeculae (µm), trabecular area (%) and trabecular bone number (per mm) and reduced trabecular separation (mm), compared with the OVX group. In addition, the ratio of OPG to RANKL and LRP5, β-catenin and Runx2 expression were significantly upregulated, while the expression of phosphorylated (p)-p38 and p-JNK were downregulated in EA-treated groups compared with the OVX group.

CONCLUSION

EA attenuates PMOP and it appears that the mechanism involves the regulation of multiple targets and pathways.

Targeting oncogenic transcription factors by polyphenols: A novel approach for cancer therapy

Inflammation is one of the major causative factor of cancer and chronic inflammation is involved in all the major steps of cancer initiation, progression metastasis and drug resistance. The molecular mechanism of inflammation driven cancer is the complex interplay between oncogenic and tumor suppressive transcription factors which include FOXM1, NF-kB, STAT3, Wnt/β- Catenin, HIF-1α, NRF2, androgen and estrogen receptors. Several products derived from natural sources modulate the expression and activity of multiple transcription factors in various tumor models as evident from studies conducted in cell lines, pre-clinical models and clinical samples. Further combination of these natural products along with currently approved cancer therapies added an additional advantage and they considered as promising targets for prevention and treatment of inflammation and cancer. In this review we discuss the application of multi-targeting natural products by analyzing the literature and future directions for their plausible applications in drug discovery.

Chloroform extract of Hedyotis diffusa Willd inhibits viability of human colorectal cancer cells via suppression of AKT and ERK signaling pathways

Hedyotis diffusa Willd (HDW) is a widely used traditional Chinese medicine in clinical therapy to treat various types of cancer, including colorectal cancer (CRC), but its effective polar fractions and functional mechanisms remain unclear. The aim of the present study was to determine the most effective extract of HDW and to investigate its effects on the regulation of CRC cell proliferation and apoptosis, as well as to investigate the underlying molecular mechanisms. The results demonstrated that the chloroform extract of HDW (CEHDW) exhibited the most anticancer ability. Furthermore, results of the MTT assay, colony formation, carboxyfluorescein diacetate succinimidyl ester assay and annexin V/propidium iodide staining suggested that CEHDW significantly inhibits proliferation and promotes apoptosis in the SW620 CRC cell line. Additionally, reverse transcription-polymerase chain reaction and western blot analysis demonstrated that CEHDW treatment downregulated the expression of Survivin, proliferating cell nuclear antigen, Cyclin D1, cyclin-dependent kinase 4 and B-cell lymphoma 2 (Bcl-2), and upregulated the expression of Bcl-2-associated X protein at the mRNA and protein levels. CEHDW also decreased the phosphorylation of protein kinase B (AKT) and extracellular-signal-regulated kinase (ERK), which indicated that the suppression of the AKT and ERK signaling pathways may be one of the underlying molecular mechanisms by which CEHDW exhibited its anticancer effect. Thus, CEHDW may be a promising agent for anticancer therapy.

Effects of ursolic and oleanolic on SK‑MEL‑2 melanoma cells: In vitro and in vivo assays

Among the triterpenoids, oleanolic acid (OA) and its isomer, ursolic acid (UA) are promising therapeutic candidates, with potential benefits in the management of melanoma. In this study, we aimed to examine the in vitro and in vivo anti‑invasive and anti‑metastatic activity of OA and UA to determine their possible usefulness as chemopreventive or chemotherapeutic agents in melanoma. For the in vitro experiments, the anti‑proliferative activity of the triterpenic compounds on SK‑MEL‑2 melanoma cells was examined. The anti‑invasive potential was assessed by testing the effects of the active compound on vascular cell adhesion molecule (VCAM) and intercellular adhesion molecule (ICAM) adhesion to melanoma cells. Normal and tumor angiogenesis were evaluated in vivo by chicken embryo chorioallantoic membrane (CAM) assay. The two test triterpenoid acids, UA and OA, exerted differential effects in vitro and in vivo on the SK‑MEL‑2 melanoma cells. UA exerted a significant and dose‑dependent anti‑proliferative effect in vitro, compared to OA. The cytotoxic effects in vitro on the melanoma cells were determined by the examining alterations in the cell cycle phases induced by UA that lead to cell arrest in the S phase. Moreover, UA was found to affect SK‑MEL‑2 melanoma cell invasiveness by limiting the cell adhesion capacity to ICAM molecules, but not influencing their adhesion to VCAM molecules. On the whole, in this study, by assessing the effects of the two triterpenoids in vivo, our results revealed that OA had a greater potential to impair the invasive capacity and tumor angiogenesis compared with UA.

Cyclooxygenase-2 mediated synergistic effect of ursolic acid in combination with paclitaxel against human gastric carcinoma

Ursolic acid (UA) induces apoptosis in gastric cancer cells by inhibiting cyclooxygenase-2 (COX-2). Paclitaxel (PTX) is an important chemotherapy agent used to treat solid tumors. We evaluated the in vitro antitumor activity of UA in combination with PTX against gastric cancer cells and investigated the mechanisms underlying the combined effects. A cytotoxicity test and flow cytometry were utilized to study the effects of UA and PTX on proliferation and apoptosis, respectively. To further elucidate the mechanism, Western blot analysis was used to assess changes in the expression of a series of related proteins, including COX-2, proliferating cell nuclear antigen (PCNA), Bcl-2, and Bax. UA and PTX dose- and time-dependently inhibited BGC-823 and SGC-7901 gastric cancer cell proliferation. Combined delivery of UA and PTX synergistically reduced cell proliferation and induced apoptosis in these cells by lowering COX-2, PCNA, and Bcl-2 expression and by increasing Bax expression. These results indicate that the synergistic inhibition of proliferation and induction of apoptosis by UA and PTX may be induced by reducing COX-2 expression in gastric cancer cells.

Hedgehog signaling pathway in colorectal cancer: function, mechanism, and therapy

Colorectal cancer (CRC) is one of the most common gastrointestinal cancers worldwide. It is a complicated and often fatal cancer, and is related to a high disease-related mortality. Around 90% of mortalities are caused by the metastasis of CRC. Current treatment statistics shows a less than 5% 5-year survival for patients with metastatic disease. The development and metastasis of CRC involve multiple factors and mechanisms. The Hedgehog (Hh) signaling plays an important role in embryogenesis and somatic development. Abnormal activation of the Hh pathway has been proven to be related to several types of human cancers. The role of Hh signaling in CRC, however, remains controversial. In this review, we will go through previous literature on the Hh signaling and its functions in the formation, proliferation, and metastasis of CRC. We will also discuss the potential of targeting Hh signaling pathway in the treatment, prognosis, and prevention of CRC.

Ursolic acid and mechanisms of actions on adipose and muscle tissue: a systematic review

This systematic review aimed at addressing the ursolic acid actions as an adjunctive treatment of the obesity-mediated metabolic abnormalities. To explore our aims, we used the literature search including clinical and animal studies using the Medline and Google Scholar (up to December 2015). Out of 63 screened studies, 17 presented eligibility criteria, such as the use of ursolic acid on adiposity, energy expenditure and skeletal muscle mass in mice and humans. In the literature, we found that several physiological and molecular mechanisms are implicated in the effects of ursolic acid on obesity, energy expenditure, hepatic steatosis, skeletal muscle mass loss and physical fitness, such as (1) increase of thermogenesis by modulation adipocyte transcription factors, activation of 5' adenosine monophosphate-activated protein kinase and overexpression of the uncoupling protein 1 thermogenic marker; (2) enhancement of skeletal muscle mass by activation in bloodstream growth hormone and insulin-like growth factor-1 concentrations secretion, as well as in the activation of mammalian target of rapamycin and inhibition of ring-finger protein-1; and (3) improvement of physical fitness by skeletal muscle proliferator-activated receptor gamma co-activator alpha and sirtuin 1 expression. Therefore, supplementation with ursolic acid may be an adjunctive therapy for prevention and treatment of obesity-mediated and muscle mass-mediated metabolic consequences.

Comparative proteomics-network analysis of proteins responsible for ursolic acid-induced cytotoxicity in colorectal cancer cells

Ursolic acid is a key active compound present in many medicinal herbs that have been widely used in traditional Chinese medicine for the clinical treatment of various cancers. However, the precise mechanisms of its antitumor activity have been poorly understood. To identify the cellular targets of ursolic acid, two-dimensional gel electrophoresis combined with mass spectrometry was performed in this study, which identified 15 proteins with significantly altered levels in protein expression. This demonstrated that ursolic acid-induced cytotoxicity in colorectal cancer cells involves dysregulation in protein folding, signal transduction, cell proliferation, cell cycle, and apoptosis. Corresponding protein regulation was also confirmed by Western blotting. Furthermore, the study of functional association between these 15 proteins revealed that 10 were closely related in a protein-protein interaction network, whereby the proteins either had a direct interaction with each other or were associated via only one intermediary protein. In this instance, the ATP5B/CALR/HSP90B1/HSPB1/HSPD1-signaling network was revealed as the predominant target which was associated with the majority of the observed protein-protein interactions. As a result, the identified targets may be useful in explaining the anticancer mechanisms of ursolic acid and as potential targets for colorectal cancer therapy.