Natural scaffolds in anticancer therapy and precision medicine

Exploring CDKN1A Upregulation Mechanisms: Insights into Cell Cycle Arrest Induced by NC2603 Curcumin Analog in MCF-7 Breast Cancer Cells

Breast cancer stands out as one of the most prevalent malignancies worldwide, necessitating a nuanced understanding of its molecular underpinnings for effective treatment. Hormone receptors in breast cancer cells substantially influence treatment strategies, dictating therapeutic approaches in clinical settings, serving as a guide for drug development, and aiming to enhance treatment specificity and efficacy. Natural compounds, such as curcumin, offer a diverse array of chemical structures with promising therapeutic potential. Despite curcumin's benefits, challenges like poor solubility and rapid metabolism have spurred the exploration of analogs. Here, we evaluated the efficacy of the curcumin analog NC2603 to induce cell cycle arrest in MCF-7 breast cancer cells and explored its molecular mechanisms. Our findings reveal potent inhibition of cell viability (IC50 = 5.6 μM) and greater specificity than doxorubicin toward MCF-7 vs. non-cancer HaCaT cells. Transcriptome analysis identified 12,055 modulated genes, most notably upregulation of GADD45A and downregulation of ESR1, implicating CDKN1A-mediated regulation of proliferation and cell cycle genes. We hypothesize that the curcumin analog by inducing GADD45A expression and repressing ESR1, triggers the expression of CDKN1A, which in turn downregulates the expression of many important genes of proliferation and the cell cycle. These insights advance our understanding of curcumin analogs' therapeutic potential, highlighting not just their role in treatment, but also the molecular pathways involved in their activity toward breast cancer cells.

Biological properties of caffeine, (+)-catechin, and theobromine: an in silico study

We analyzed here the in silico biological activities of caffeine, (+)-catechin, and theobromine. For this, the PubChem database of the NIH (National Institutes of Health) was used to obtain the SMILE canonical form of the bioactive molecules, and the free software PASS Online (Prediction of Activity Spectra for Substances) from the Way2Drug portal. Also, we conducted an in vitro experiment using a chronic myeloid leukemia (CML) cell line (K562) to confirm some results found in in silico investigation. These cells were exposed to different concentrations of caffeine, (+)-catechin, and theobromine for 72 h. The results found in this in silico study suggested that caffeine, (+)-catechin, and theobromine showed excellent biological properties, such as antioxidant, anti-inflammatory, and anticarcinogenic, as well as protection against cardiovascular, diabetes, neurological, allergic, respiratory, and other therapeutic activities. These findings can be elucidated through the modulation exerted by these bioactive molecules in many biochemical pathways involved in organism homeostasis, such as free radical scavenger action, oxidoreductase inhibitor, membrane permeability inhibitor, and lipid peroxidase inhibitor. In addition, we have found here that caffeine, (+)-catechin, and theobromine have a remarkable anti-inflammatory activity which plays an important role in the therapeutic approach of COVID-19. Moreover, our in vitro findings confirmed the in silico results regarding anticancer activity since these molecules reduce cell proliferation at all tested concentrations. Therefore, since these molecules exhibit important medicinal activities, further investigations should be conducted to reveal new therapies to improve the treatments and prevention of numerous disorders and, consequently, promote human health.

Paucatalinone A from Paulownia Catalpifolia Gong Tong Elicits mitochondrial-mediated cancer cell death to combat osteosarcoma

As the global cancer burden escalates, the search for alternative therapies becomes increasingly vital. Natural products, particularly plant-derived compounds, have emerged as promising alternatives to conventional cancer treatments due to their diverse bioactivities and favorable biosafety profiles. Here, we investigate Paucatalinone A, a newly discovered geranylated flavanone derived from the fruit of Paulownia Catalpifolia Gong Tong, notable for its significant anti-cancer properties. We revealed the capability of Paucatalinone A to induce apoptosis in osteosarcoma cells and deciphered its underlying mechanisms. Our findings demonstrate that Paucatalinone A substantially augments apoptosis, inhibits cell proliferation, and demonstrates a pronounced anti-tumor effect in a murine model of osteosarcoma. Mechanistically, Paucatalinone A disrupts calcium homeostasis and exacerbates intracellular reactive oxygen species accumulation, leading to mitochondrial impairment, cytoskeletal collapse, and caspase-dependent apoptotic cell death. This study underscores the potential of Paucatalinone A in initiating apoptosis in cancer cells and highlights the therapeutic efficacy of plant-derived agents in treating osteosarcoma, offering a viable approach for managing other intractable cancers.

Regulated cell death in glioma: promising targets for natural small-molecule compounds

Gliomas are prevalent malignant tumors in adults, which can be categorized as either localized or diffuse gliomas. Glioblastoma is the most aggressive and deadliest form of glioma. Currently, there is no complete cure, and the median survival time is less than one year. The main mechanism of regulated cell death involves organisms coordinating the elimination of damaged cells at risk of tumor transformation or cells hijacked by microorganisms for pathogen replication. This process includes apoptosis, necroptosis, autophagy, ferroptosis, pyroptosis, necrosis, parthanayosis, entosis, lysosome-dependent death, NETosis, oxiptosis, alkaliptosis, and disulfidaptosis. The main goal of clinical oncology is to develop therapies that promote the effective elimination of cancer cells by regulating cell death are the main goal of clinical oncology. Recently, scientists have utilized pertinent regulatory factors and natural small-molecule compounds to induce regulated cell death for the treatment of gliomas. By analyzing the PubMed and Web of Science databases, this paper reviews the research progress on the regulation of cell death and the role of natural small-molecule compounds in glioma. The aim is to provide help for the treatment of glioblastoma.

Chemical and cytotoxicity profiles of 11 pink pepper (Schinus spp.) samples via non-targeted hyphenated high-performance thin-layer chromatography

INTRODUCTION

Pink pepper is a worldwide used spice that corresponds to the berries of two species, Schinus terebinthifolia Raddi or S. molle L. (Anacardiaceae). Toxic and allergic reactions by ingestion or contact with these plants were reported, and classical in vitro studies have highlighted the cytotoxic properties of apolar extracts from the fruits.

OBJECTIVES

Perform a non-targeted screening of 11 pink pepper samples for the detection and identification of individual cytotoxic substances.

METHODS

After reversed-phase high-performance thin-layer chromatography (RP-HPTLC) separation of the extracts and multi-imaging (UV/Vis/FLD), cytotoxic compounds were detected by bioluminescence reduction from luciferase reporter cells (HEK 293 T-CMV-ELuc) applied directly on the adsorbent surface, followed by elution of detected cytotoxic substance into atmospheric-pressure chemical ionization high-resolution mass spectrometry (APCI-HRMS).

RESULTS

Separations for mid-polar and non-polar fruit extracts demonstrated the selectivity of the method to different substance classes. One cytotoxic substance zone was tentatively assigned as moronic acid, a pentacyclic triterpenoid acid.

CONCLUSION

The developed non-targeted hyphenated RP-HPTLC-UV/Vis/FLD-bioluminescent cytotoxicity bioassay-FIA-APCI-HRMS method was successfully demonstrated for cytotoxicity screening (bioprofiling) and respective cytotoxin assignment.

Fabrication of bovine serum albumin-polyethylene glycol nanoparticle conjugated-folic acid loaded-naringenin as an efficient carrier biomacromolecule for suppression of cancer cells

Flavonoid compounds play an effective role in cancer suppression and today nanocarriers play an important role in improving the physicochemical properties and transmission of these compounds. In this study, polyethylene glycol-modified albumin nanoparticles were synthesized by desolvation method; after loading of naringenin (NRG), folic acid (FA) binding to the surface of nanoparticles was performed (BSA-PEG-FA-NG-NPs). The extent of NRG trapping and FA binding was assessed indirectly using UV absorption methods. The physicochemical properties of BSA-PEG-FA-NG-NPs were investigated by DLS, SEM electron microscopy, and FTIR methods, after which their effects were evaluated on the apoptosis mechanism via MTT, flow cytometry, and qPCR methods. The BSA-PEG-FA-NG-NPs with spherical morphology had dimensions of 205 nm with zeta-potential of 20.61 mV and dispersion index of 0.36. The NRG encapsulation was 84% and the FA binding was 75%. Anticancer effects of BSA-PEG-FA-NG-NPs were confirmed based on inhibiting breast cancer cells (IC50: 922 µg/ml), cell cycle arrest (SubG1 phase), and induction of apoptosis (upregulation of Caspase 3, 8, and 9).

When Natural Compounds Meet Nanotechnology: Nature-Inspired Nanomedicines for Cancer Immunotherapy

Recent significant strides of natural compounds in immunomodulation have highlighted their great potential against cancer. Despite many attempts being made for cancer immunotherapy, the biomedical application of natural compounds encounters a bottleneck because of their unclear mechanisms, low solubility and bioavailability, and limited efficacy. Herein, we summarize the immune regulatory mechanisms of different natural compounds at each step of the cancer-immunity cycle and highlight their anti-tumor potential and current limitations. We then propose and present various drug delivery strategies based on nanotechnology, including traditional nanoparticles (NPs)-based delivery strategies (lipid-based NPs, micelles, and polysaccharide/peptide/protein-based NPs) and novel delivery strategies (cell-derived NPs and carrier-free NPs), thus providing solutions to break through existing bottlenecks. Furthermore, representative applications of nature-inspired nanomedicines are also emphasized in detail with the advantages and disadvantages discussed. Finally, the challenges and prospects of natural compounds for cancer immunotherapy are provided, hopefully, to facilitate their far-reaching development toward clinical translation.

A Quassinoid Diterpenoid Eurycomanone from Eurycoma longifolia Jack Exerts Anti-Cancer Effect through Autophagy Inhibition

Eurycomanone (EN) is one of the representative quassinoid diterpenoids from roots of Eurycoma longifolia Jack, a natural medicine that is widely distributed in Southeast Asia. Previous studies showed that EN induces cancer cell apoptosis and exhibits anti-cancer activity, but the molecular mechanism of EN against cancer has still not been elucidated. In this study, we examined the regulatory effect of EN on autophagy to reveal the mechanism of EN-mediated colon cancer growth inhibition. First, we found that EN is able to inhibit colon cancer cell proliferation and colony formation. The angiogenesis level in cancer cells was inhibited as well. Next, the treatment of EN led to the suppression of autophagy, which was characterized by the downregulation of the LC3-II level and the formation of GFP-LC3 puncta under EN treatment in colon cancer. Moreover, we revealed that the mTOR signaling pathway was activated by EN in a time- and concentration-dependent manner. Finally, autophagy induction protected colon cancer cells from EN treatment, suggesting that autophagy improves cell survival. Taken together, our findings revealed the mechanism of EN against colon cancer through inhibiting autophagy and angiogenesis in colon cancer, supporting that the autophagy inhibitor EN could be developed to be a novel anti-cancer agent.

A brief overview of classical natural product drug synthesis and bioactivity

This manuscript briefly overviewed the total synthesis and structure–activity relationship studies of eight classical natural products, which emphasizes the important role of total synthesis in natural product-based drug development.

Advanced Computational Methodologies Used in the Discovery of New Natural Anticancer Compounds

Natural chemical compounds have been widely investigated for their programmed necrosis causing characteristics. One of the conventional methods for screening such compounds is the use of concentrated plant extracts without isolation of active moieties for understanding pharmacological activity. For the last two decades, modern medicine has relied mainly on the isolation and purification of one or two complicated active and isomeric compounds. The idea of multi-target drugs has advanced rapidly and impressively from an innovative model when first proposed in the early 2000s to one of the popular trends for drug development in 2021. Alternatively, fragment-based drug discovery is also explored in identifying target-based drug discovery for potent natural anticancer agents which is based on well-defined fragments opposite to use of naturally occurring mixtures. This review summarizes the current key advancements in natural anticancer compounds; computer-assisted/fragment-based structural elucidation and a multi-target approach for the exploration of natural compounds.

Plumbagin Enhances the Radiosensitivity of Tongue Squamous Cell Carcinoma Cells via Downregulating ATM

This study was designed to investigate whether plumbagin (PL) could sensitize ionizing radiation (IR) in tongue squamous cell carcinoma (TSCC) cells and its possible mechanisms. Cell proliferation and combination index analysis was based on MTT and colony formation assay. Flow cytometry was applied to analyze the cell cycle distribution and apoptosis after the treatment of PL and/or IR. RT-PCR was used to examine the gene expression level of ataxia telangiegatasiata muted (ATM) and nuclear factor kappa beta (NF-κB) after various treatment groups. Western blot was used to examine the protein level of ATM and NF-κB as well as their phosphorylation level. PL enhances the cytotoxicity of IR in TSCC cells. Combination index was <1 which represents a synergistic effect. Combined PL and IR promoted G2/M arrest and apoptosis which could be reversed by ATM activator chloroquine phosphate. ATM and NF-κB were both inhibited by PL and IR combination. PL can efficiently enhance the radiosensitivity of TSCC cells by inducing G2/M arrest and apoptosis via downregulating ATM.

Identification of differentially expressed circular RNAs in human nasopharyngeal carcinoma

BACKGROUND

Circular RNAs (circRNAs) are endogenous RNAs that have a covalent closed cycle configuration. circRNAs have been found to be differentially expressed in many human cancers. Therefore, circRNAs may be ideal biomarkers for the diagnosis and treatment of cancer. However, we know very little about the function of circRNAs in nasopharyngeal carcinoma (NPC). The purpose of this study was to evaluate the circRNA expression profiles in NPC.

METHODS

We utilized high-throughput RNA sequencing (RNA-Seq) to evaluate the circRNA expression profile in NPC A total of 13,561 unique circRNA candidates were detected. Selection of aberrantly expressed circRNAs was carried out using a q-value of < 0.001 with a fold change of > 2.0 or < 0.5. We carried out Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses to identify the biological functions of differentially expressed circRNAs. Moreover, bioinformatics analyses were implemented to predict the effects between circRNAs and cancer-related microRNAs (miRNAs), and we used Cytoscape to build a cancer-related circRNA-miRNA target gene map. Finally, to verify dysregulated circRNAs, quantitative real-time PCR was utilized.

RESULTS

In NPC tissues, we found that 73 circRNAs were downregulated and 59 were upregulated. The top 12 candidate circRNAs were selected from several vital NPC pathways such as the human papillomavirus and Epstein-Barr virus infection signaling pathways (hsa05165 and hsa05169, respectively), Hepatitis B (hsa05161), and the Ras signaling pathway (hsa04014). A network map of circRNA-miRNA interactions of 12 differentially expressed circRNAs was built. Hsa_circ_0007637 expression distinguished NPC tissues from paired healthy tissues and NPC cell lines (HNE1 6-10B, 5-8F, CNE-2, and so on) from a normal epithelial (NP460) cell line.

CONCLUSIONS

In this study, we investigated the profiles of differentially expressed circRNAs in NPC, and our results show that hsa_circ_0007637 may be a biomarker for NPC and play a role in its development. This observation-based research identified dysregulated circRNAs in NPC, which may assist in the development of biomarkers for this disease. Further studies on the mechanisms and functions of these circRNAs may promote our understanding of NPC tumorigenesis.

Preclinical safety assessment of the crude extract from Sida rhombifolia L. aerial parts in experimental models of acute and repeated-dose 28 days toxicity in rats

Sida rhombifolia (Malvaceae) is popularly used as a treatment for several pathological conditions; however, there is a lack of studies that identify its compounds and that evaluate comprehensively the safety of its consumption. Therefore, the aim of this study was to determinate the phytochemical constitution of the crude extract of Sida rhombifolia (CESR), and its safety in models of acute and repeated doses (28 days) toxicity. The tested dose for the model of acute toxicity was 2000 mg/kg doses for the repeated dose model were 150, 300 e 600 mg/kg. Hematological, biochemical, histopathological and oxidative markers were investigated. HPLC-DAD-MS analysis evidenced the presence of caffeic acid, coumarin, and rutin. In the acute toxicity model the only altered parameters were tissue ROS, and AST and BUN in serum. As for the repeated dose experiment both hematological and biochemical markers remained within the values of reference for the species. Obtained results demonstrate that the CESR did not present significant toxic effects when administrated orally to male and female rats in acute and repeated doses.

Chemotherapeutic drugs: Cell death- and resistance-related signaling pathways. Are they really as smart as the tumor cells?

Chemotherapeutic drugs kill cancer cells or control their progression all over the patient's body, while radiation- and surgery-based treatments perform in a particular site. Based on their mechanisms of action, they are classified into different groups, including alkylating substrates, antimetabolite agents, anti-tumor antibiotics, inhibitors of topoisomerase I and II, mitotic inhibitors, and finally, corticosteroids. Although chemotherapeutic drugs have brought about more life expectancy, two major and severe complications during chemotherapy are chemoresistance and tumor relapse. Therefore, we aimed to review the underlying intracellular signaling pathways involved in cell death and resistance in different chemotherapeutic drug families to clarify the shortcomings in the conventional single chemotherapy applications. Moreover, we have summarized the current combination chemotherapy applications, including numerous combined-, and encapsulated-combined-chemotherapeutic drugs. We further discussed the possibilities and applications of precision medicine, machine learning, next-generation sequencing (NGS), and whole-exome sequencing (WES) in promoting cancer immunotherapies. Finally, some of the recent clinical trials concerning the application of immunotherapies and combination chemotherapies were included as well, in order to provide a practical perspective toward the future of therapies in cancer cases.

Isoliensinine: A Natural Compound with "Drug-Like" Potential

Isoliensinine, a bisbenzylisoquinoline alkaloid isolated from Nelumbo nucifera Gaertn, exerts a variety of beneficial effects, such as antitumor, cardioprotective, antioxidant, antidepressant, and anti-HIV effects, and ameliorates T2DM with hyperlipidemia and Alzheimer’s disease. In this article, the recent literature on isoliensinine, including its pharmacology, pharmacokinetics, and synthesis and extraction, is summarized. Moreover, possible future prospects and research directions are also discussed. Studies on isoliensinine were found by searching a combination of keywords including “pharmacology,” “pharmacokinetics,” and “synthesis and extraction” in the main databases, including PubMed, Google Scholar, Web of Science, NCBI, and Wan Fang. Many studies have pointed out that a major limitation of isoliensinine is its poor solubility in aqueous media. Considering its advantages and limitations, isoliensinine can be used as a lead compound to develop novel efficient and low-toxicity derivatives. The available literature indicates that isoliensinine displays “drug-like” potential. Additionally, there are many related issues and novel mechanisms that need to be explored.

Synthesis and Characterization of Diosgenin Encapsulated Poly-ε-Caprolactone-Pluronic Nanoparticles and Its Effect on Brain Cancer Cells

Diosgenin encapsulated PCL-Pluronic nanoparticles (PCL-F68-D-NPs) were developed using the nanoprecipitation method to improve performance in brain cancer (glioblastoma) therapy. The nanoparticles were characterized by dynamic light scattering (DLS)/Zeta potential, Fourier-transform infrared (FTIR) spectra, X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), and Transmission electron microscopy (TEM). The encapsulation efficiency, loading efficiency, and yield were calculated. The in vitro release rate was determined, and the kinetic model of diosgenin release was plotted and ascertained. The cytotoxicity was checked by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide)assay against U87-MG cells (glioblastoma cell lines). The obtained nanoparticles demonstrated good size distribution, stability, morphology, chemical, and mechanical properties. The nanoparticles also possessed high encapsulation efficiency, loading efficiency, and yield. The release rate of Diosgenin was shown in a sustained manner. The in vitro cytotoxicity of PCL-F68-D-NPs showed higher toxicity against U87-MG cells than free Diosgenin.

Cytotoxicity of glucoevatromonoside alone and in combination with chemotherapy drugs and their effects on Na+,K+-ATPase and ion channels on lung cancer cells

Cardiac glycosides (CGs) are useful drugs to treat cardiac illnesses and have potent cytotoxic and anticancer effects in cultured cells and animal models. Their receptor is the Na⁺,K⁺ ATPase, but other plasma membrane proteins might bind CGs as well. Herein, we evaluated the short- and long-lasting cytotoxic effects of the natural cardenolide glucoevatromonoside (GEV) on non-small-cell lung cancer H460 cells. We also tested GEV effects on Na⁺,K⁺ -ATPase activity and membrane currents, alone or in combination with selected chemotherapy drugs. GEV reduced viability, migration, and invasion of H460 cells spheroids. It also induced cell cycle arrest and death and reduced the clonogenic survival and cumulative population doubling. GEV inhibited Na⁺,K⁺-ATPase activity on A549 and H460 cells and purified pig kidney cells membrane. However, it showed no activity on the human red blood cell plasma membrane. Additionally, GEV triggered a Cl-mediated conductance on H460 cells without affecting the transient voltage-gated sodium current. The administration of GEV in combination with the chemotherapeutic drugs paclitaxel (PAC), cisplatin (CIS), irinotecan (IRI), and etoposide (ETO) showed synergistic antiproliferative effects, especially when combined with GEV + CIS and GEV + PAC. Taken together, our results demonstrate that GEV is a potential drug for cancer therapy because it reduces lung cancer H460 cell viability, migration, and invasion. Our results also reveal a link between the Na⁺,K⁺-ATPase and Cl^- ion channels.

Polyphenols as a versatile component in tissue engineering

The fabrication of functional tissue or organs substitutes has always been the pursuit of goals in the field of tissue engineering. But even biocompatible tissue-engineered scaffolds still suffer from immune rejection, subsequent long-term oxidative stress and inflammation, which can delay normal tissue repair and regeneration. As a well-known natural antioxidant, polyphenols have been widely used in tissue engineering in recent years. The introduced polyphenols not only reduce the damage of oxidative stress to normal tissues, but show specific affinity to functional molecules, such as receptors, enzyme, transcription and transduction factors, etc. Therefore, polyphenols can promote the recovery process of damaged tissues by both regulating tissue microenvironment and participating in cell events, which embody specifically in antioxidant, anti-inflammatory, antibacterial and growth-promoting properties. In addition, based on its hydrophilic and hydrophobic moieties, polyphenols have been widely used to improve the mechanical properties and anti-degradation properties of tissue engineering scaffolds. In this review, the research advances of tissue engineering scaffolds containing polyphenols is discussed systematically from the aspects of action mechanism, introduction method and regulation effect of polyphenols, in order to provide references for the rational design of polyphenol-related functional scaffolds.

Diosgenin Loaded Polymeric Nanoparticles with Potential Anticancer Efficacy

This study aims to determine the anticancer efficacy of diosgenin encapsulated poly-glycerol malate co-dodecanedioate (PGMD) nanoparticles. Diosgenin loaded PGMD nanoparticles (variants 7:3 and 6:4) were synthesized by the nanoprecipitation method. The synthesis of PGMD nanoparticles was systematically optimized employing the Box-Behnken design and taking into account the influence of various independent variables such as concentrations of each PGMD, diosgenin and PF-68 on the responses such as size and PDI of the particles. Mathematical modeling was done using the Quadratic second order modeling method and response surface analysis was undertaken to elucidate the factor-response relationship. The obtained size of PGMD 7:3 and PGMD 6:4 nanoparticles were 133.6 nm and 121.4 nm, respectively, as measured through dynamic light scattering (DLS). The entrapment efficiency was in the range of 77-83%. The in vitro drug release studies showed diffusion and dissolution controlled drug release pattern following Korsmeyer-Peppas kinetic model. Furthermore, in vitro morphological and cytotoxic studies were performed to evaluate the toxicity of synthesized drug loaded nanoparticles in model cell lines. The IC50 after 48 h was observed to be 27.14 µM, 15.15 µM and 13.91 µM for free diosgenin, PGMD 7:3 and PGMD 6:4 nanoparticles, respectively, when administered in A549 lung carcinoma cell lines.

Oral administration of natural polyphenol-loaded natural polysaccharide-cloaked lipidic nanocarriers to improve efficacy against small-cell lung cancer

Oral administration shows good tolerance in patients. Botanic anticancer drugs without serious side effects have attracted increased attention worldwide. However, oral delivery of natural anticancer drugs faces great challenges due to low solubility, gastrointestinal side effects, first-pass effects, and P-glycoprotein efflux. Here, we loaded the natural polyphenol curcumin (Cc) into natural polysaccharide-cloaked lipidic nanocarriers (Cc@CLNs) to improve the efficacy in small-cell lung cancer (SCLC) associated with oral administration. Compared to other nanoformulations, Cc@CLNs have advantages of simple operation, easy scale-up, low cost, and high safety. Cc@CLNs improve bioavailability by inducing synergistic effects (efficient cell membrane penetration, inherent muco-adhesiveness, resistance to pepsin and trypsin degradation, promoted dissolution, enhanced epithelia/M cellular uptake and inhibition of efflux transporters) and countering the tendency of nanocarriers to aggregate and fuse, which limit lipid-based nanosystems. In this study, we first evaluated the oral bioavailability of Cc@CLNs in rats and their efficacy in H446 tumor-bearing mice. The oral bioavailability increased by 8.94-fold, and the tumor growth inhibition rate doubled compared to that achieved with free Cc. We investigated the action of Cc against SCLC stem cells, and Cc@CLNs greatly enhanced this action. The expression of CD133 and ABCG2 in the Cc@CLNs group decreased by 38.05% and 32.57%, respectively, compared to the respective expression levels in the control.

Improving the odds of success in antitumoral drug development using scoring approaches towards heterocyclic scaffolds

One of the most commonly discussed topics in the field of drug discovery is the continuous search for anticancer therapies, in which small-molecule development plays an important role. Although a number of techniques have been established over the past decades, one of the main methods for drug discovery and development is still represented by rational, ligand-based drug design. However, the success rate of this method could be higher if not affected by cognitive bias, which renders many potential druggable scaffolds and structures overlooked. The present study aimed to counter this bias by presenting an objective overview of the most important heterocyclic structures in the development of anti-proliferative drugs. As such, the present study analyzed data for 91,438 compounds extracted from the Developmental Therapeutics Program (DTP) database provided by the National Cancer Institute. Growth inhibition data from these compounds tested on a panel of 60 cancer cell lines representing various tissue types (NCI-60 panel) was statistically interpreted using 6 generated scores assessing activity, selectivity, growth inhibition efficacy and potency of different structural scaffolds, Bemis-Murcko skeletons, chemical features and structures common among the analyzed compounds. Of the most commonly used rings, the most prominent anti-proliferative effects were produced by quinoline, tetrahydropyran, benzimidazole and pyrazole, while overall, the optimal results were produced by complex ring structures that originate from natural compounds. These results highlight the impact of certain ring structures on the anti-proliferative effects in drug design. In addition, considering that medicinal chemists usually focus their research on simpler scaffolds the majority of the time with no significant pay-off, the present study indicates several unused complex scaffolds that could be exploited when designing anticancer therapies for optimal results in the fight against cancer.

Natural products target the hallmarks of chronic diseases

Natural compounds are known to display therapeutic potential against a variety of chronic conditions, including cancer and inflammation. The efficacy of these natural substances can be associated with numerous molecular scaffolds present in extracts of living organisms, both terrestrial and marine. Recently, investigators have identified the ability of natural compounds to trigger immunogenic cell death and subsequent activation of the adaptive immune system. Such findings indicate that the full therapeutic potential of natural products has yet to be defined, and further investigations on such agents will continue to yield novel drug candidates.

Current status and contemporary approaches to the discovery of antitumor agents from higher plants

Higher plant constituents have afforded clinically available anticancer drugs. These include both chemically unmodified small molecules and their synthetic derivatives currently used or those in clinical trials as antineoplastic agents, and an updated summary is provided. In addition, botanical dietary supplements, exemplified by mangosteen and noni constituents, are also covered as potential cancer chemotherapeutic agents. Approaches to metabolite purification, rapid dereplication, and biological evaluation including analytical hyphenated techniques, molecular networking, and advanced cellular and animal models are discussed. Further, enhanced and targeted drug delivery systems for phytochemicals, including micelles, nanoparticles and antibody drug conjugates (ADCs) are described herein.

Agriculture waste valorisation as a source of antioxidant phenolic compounds within a circular and sustainable bioeconomy

Agro-food industrial waste is currently being accumulated, pushing scientists to find recovery strategies to obtain bioactive compounds within a circular bioeconomy. Target phenolic compounds have shown market potential by means of optimization extraction techniques.

Combined extracts of Echinacea angustifolia DC. and Zingiber officinale Roscoe in softgel capsules: Pharmacokinetics and immunomodulatory effects assessed by gene expression profiling

BACKGROUND AND OBJECTIVE

Echinacea angustifolia DC. and Zingiber officinale Roscoe are two natural products with documented immunomodulatory activity, both able to modulate the expression of important immune-related genes. Thus, their use in combination seems to be particularly promising. In this context, we have considered the oral supplementation of a highly standardized lipophilic extract combining both above-mentioned phytocomplexes, formulated in attractive softgel capsules, with two objectives: on the one hand to study oral pharmacokinetic of main active extracts' components and on the other hand to examine the immunomodulation and anti-inflammatory properties by gene expression profiling.

METHODS

Softgel capsules containing a combination of E. angustifolia DC. and Z. officinale Roscoe (5 mg and 25 mg, respectively) were given by oral administration to 10 healthy volunteers. The plasma concentrations of dodeca-2E,4E,8Z,10E/Z-tetraenoic isobutylamide (tetraene) for E. angustifolia DC., 6-gingerol and 6-shogaol (free and glucuronide) for Z. officinale Roscoe were determined by LC-MS analysis, and the pharmacokinetic analysis was performed. To understand the functional mechanisms responsible for the documented health benefits, we also examined the overall transcriptional remodeling induced in the peripheral blood mononuclear cells and performed an integrative functional analysis on the generated gene expression.

RESULTS

All bioactive components were absorbed very rapidly, and their tmax were detected in plasma from 30 min to 1.40 h. The peak concentrations of tetraene, 6-gingerol, 6-shogaol and their glucuronide metabolites were 14.74, 5.66, 9.25, 29.2 and 22.24 ng/ml, respectively. Integrated analysis performed on the generated gene expression data highlighted immunomodulatory and anti-inflammatory effects similar to those exerted by hydrocortisone.

CONCLUSION

These data demonstrated that the bioactive ingredients are highly and rapidly absorbed from softgel capsules containing the combination of the above-mentioned lipophilic extracts, providing evidence to support their immunomodulatory and anti-inflammatory properties. These data also help in defining the mechanistic pathways underlying the health benefits of these plant-derived bioactive compounds.

Natural compound inducers of immunogenic cell death

Accumulating evidence shows that the anti-cancer potential of the immune response that can be activated by modulation of the immunogenicity of dying cancer cells. This regulated cell death process is called immunogenic cell death (ICD) and constitutes a new innovating anti-cancer strategy with immune-modulatory potential thanks to the release of damage-associated molecular patterns (DAMPs). Some conventional clinically-used chemotherapeutic drugs, as well as preclinically-investigated compounds of natural origins such as anthracyclines, microtubule-destabilizing agents, cardiac glycosides or hypericin derivatives, possess such an immune-stimulatory function by triggering ICD. Here, we discuss the effects of ICD inducers on the release of DAMPs and the activation of corresponding signaling pathways triggering immune recognition. We will discuss potential strategies allowing to overcome resistance mechanisms associated with this treatment approach as well as co-treatment strategies to overcome the immunosuppressive microenvironment. We will highlight the potential role of metronomic immune modulation as well as targeted delivery of ICD-inducing compounds with nanoparticles or liposomal formulations to improving the immunogenicity of ICD inducers aiming at long-term clinical benefits.

Role of Endoplasmic Reticulum Stress in the Anticancer Activity of Natural Compounds

Cancer represents a serious global health problem, and its incidence and mortality are rapidly growing worldwide. One of the main causes of the failure of an anticancer treatment is the development of drug resistance by cancer cells. Therefore, it is necessary to develop new drugs characterized by better pharmacological and toxicological profiles. Natural compounds can represent an optimal collection of bioactive molecules. Many natural compounds have been proven to possess anticancer effects in different types of tumors, but often the molecular mechanisms associated with their cytotoxicity are not completely understood. The endoplasmic reticulum (ER) is an organelle involved in multiple cellular processes. Alteration of ER homeostasis and its appropriate functioning originates a cascade of signaling events known as ER stress response or unfolded protein response (UPR). The UPR pathways involve three different sensors (protein kinase RNA(PKR)-like ER kinase (PERK), inositol requiring enzyme1α (IRE1) and activating transcription factor 6 (ATF6)) residing on the ER membranes. Although the main purpose of UPR is to restore this organelle's homeostasis, a persistent UPR can trigger cell death pathways such as apoptosis. There is a growing body of evidence showing that ER stress may play a role in the cytotoxicity of many natural compounds. In this review we present an overview of different plant-derived natural compounds, such as curcumin, resveratrol, green tea polyphenols, tocotrienols, and garcinia derivates, that exert their anticancer activity via ER stress modulation in different human cancers.

Natural modulators of the hallmarks of immunogenic cell death

Natural compounds act as immunoadjuvants as their therapeutic effects trigger cancer stress response and release of damage-associated molecular patterns (DAMPs). These reactions occur through an increase in the immunogenicity of cancer cells that undergo stress followed by immunogenic cell death (ICD). These processes result in a chemotherapeutic response with a potent immune-mediating reaction. Natural compounds that induce ICD may function as an interesting approach in converting cancer into its own vaccine. However, multiple parameters determine whether a compound can act as an ICD inducer, including the nature of the inducer, the premortem stress pathways, the cell death pathways, the intrinsic antigenicity of the cell, and the potency and availability of an immune cell response. Thus, the identification of hallmarks of ICD is important in determining the prognostic biomarkers for new therapeutic approaches and combination treatments.