Substances of Natural Origin in Medicine: Plants vs. Cancer

Bioactives derived from Brazilian native flora with antimicrobial and anticancer activity

BACKGROUND

The development of new drugs that act against multidrug-resistant microorganisms and malignant tumors is necessary owing to the limited therapeutic options and high mortality rates associated with these pathologies. In this study, we evaluated the phytochemical groups present in seven plants from the Brazilian Cerrado even as their antioxidant, antiproliferative and antimicrobial activities.

METHODS

The extracts were obtained by the maceration technique and secondary metabolites were determined by phytochemical analysis. The antioxidant activity was assessed by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging method. The antiproliferative activity of the extracts was assessed using human breast, kidney, and liver neoplastic cells. Cytotoxicity was evaluated in a non-neoplastic cell line - NIH/3T3. The antimicrobial activity of the plant extracts against resistant bacteria and yeasts was determined using disk diffusion assays, and the minimum inhibitory concentration (MIC) was determined by the broth microdilution technique.

RESULTS

Phytochemical analysis revealed the presence of phenolic compounds, flavonoids, steroids, tannins, and saponins in all of the extracts, with Smilax fluminensis showing the highest levels of phenolic compounds and flavonoids. All tested extracts exhibited antioxidant activity above 50%, notably Tapiria obtusa (82.36 ± 0.44). The T. obtusa extract showed potent antiproliferative activity against the 786-0 cell line (GI50 10.16 ± 2.33 µg/mL) and a significantly greater SI (SI = 24.61) than the control (SI = 3.23, doxorubicin), indicating its selective cytotoxicity against cancer cells and its potential as a therapeutic agent against renal cancer. No cytotoxicity was observed in non-tumor cells. Extracts of S. fluminensis leaves showed fungicidal effects on Candida glabrata (MIC = 500 µg/mL). This study is the first to demonstrate the antibacterial activity of T. obtusa leaf ethanolic extract against MRSA (MIC = 1,000 µg/mL).

CONCLUSIONS

The ethanolic extract of T. obtusa demonstrated antioxidant activity, antiproliferative effects against the 786-0 cell line, and antibacterial activity against MRSA. The ethanolic extract of S. fluminensis leaves exhibited a fungicidal effect against C. glabrata. These findings may pave the way for more effective and safer treatments for managing oncological and infectious diseases.

Antitumor Activity, Mechanisms of Action and Phytochemical Profiling of Sub-Fractions Obtained from Ulex gallii Planch. (Fabaceae): A Medicinal Plant from Galicia (Spain)

The plant kingdom serves as a valuable resource for cancer drug development. This study explored the antitumor activity of different sub-fractions (hexane, dichloromethane and methanol) of U. gallii (gorse) methanol extract in glioblastoma (U-87MG and U-373MG) and neuroblastoma (SH-SY5Y) cell lines, along with their phytochemical profiles. Cytotoxicity was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays, and cell cycle arrest and apoptosis were assessed through flow cytometry and by measuring reactive oxygen species (ROS) and protein expression levels. D7 and D8 dichloromethane sub-fractions significantly reduced cell viability, triggered early apoptosis in SH-SY5Y and U-87MG cells and specifically increased ROS levels in U-87MG cells. Western blot analyses showed that D7 increased p53, caspase-3, caspase-8 and γH2AX expression in SH-SY5Y and U-87MG cells, while D8 specifically elevated p53 in SH-SY5Y cells and caspase-3 in both cell lines. In U-373 cells, D7 and D8 markedly reduced cell viability, with D8 inducing necrosis. Morphological changes indicative of apoptosis were also observed in all cell lines. Bioinformatic analysis of UHPLC-MS and GC-MS data tentatively identified 20 metabolites in D7 and 15 in D8, primarily flavonoids. HPLC-DAD confirmed isoprunetin and genistein as the most abundant in D7 and D8, respectively, both isolated and identified by NMR spectroscopy. Most of the flavonoids identified have been reported as antitumor agents, suggesting that these compounds may be responsible for the observed pharmacological activity.

Modification in Structures of Active Compounds in Anticancer Mitochondria-Targeted Therapy

Cancer is a multifaceted disease characterised by uncontrolled cellular proliferation and metastasis, resulting in significant global mortality. Current therapeutic strategies, including surgery, chemotherapy, and radiation therapy, face challenges such as systemic toxicity and tumour resistance. Recent advancements have shifted towards targeted therapies that act selectively on molecular structures within cancer cells, reducing off-target effects. Mitochondria have emerged as pivotal targets in this approach, given their roles in metabolic reprogramming, retrograde signalling, and oxidative stress, all of which drive the malignant phenotype. Targeting mitochondria offers a promising strategy to address these mechanisms at their origin. Synthetic derivatives of natural compounds hold particular promise in mitochondrial-targeted therapies. Innovations in drug design, including the use of conjugates and nanotechnology, focus on optimizing these compounds for mitochondrial specificity. Such advancements enhance therapeutic efficacy while minimizing systemic toxicity, presenting a significant step forward in modern anticancer strategies.

Design of Bionanomaterial of Chitosan Carbohydrate Polymer Composited with Broccoli Extract and Zinc Oxide Nanoparticles: Anticancer Activity in Human Osteosarcoma

In the current research, a chitosan/broccoli extract/ZnO nanoparticle (CH/BE/ZnO) bionanocomposite was created. The physicochemical properties of CH/BE/ZnO bionanocomposite were investigated using a variety of methods, including field emission scanning electron microscopy (FESEM), elemental analysis (CHN-O), X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR), Brunauer-Emmett-Teller (BET), and transmission electron microscopy (TEM). The CH/BE/ZnO bionanocomposite's biological activity was assessed by examining its cytotoxicity capabilities against a bone cancer cell line (MG63). The total pore volume and specific surface area of CH/BE/ZnO are 0.134 cm3/g and 16.99 m2/g, respectively. The IC50 results for CH/BE/ZnO bionanocomposite in bone cancer investigations using the MTT test against the MG63 cell line was 115 μg/mL. The results indicate that the CH/BE/ZnO bionanocomposite is an effective chemotherapeutic agent against human osteosarcoma. The CH/BE/ZnO bionanocomposite showed high performance and structure, which means innovating nanomaterial agents for biological applications in the future.

Chemical Composition and Bioactivity Dataset Integration to Identify Antiproliferative Compounds in Phyllanthus Plants

BACKGROUND/OBJECTIVES

Phyllanthus species are renowned in traditional medicine for their diverse therapeutic properties, including potential anticancer activities. This study explored the antiproliferative potential of six Phyllanthus species by integrating chemical composition with bioactivity assays to identify key antiproliferative compounds.

METHODS

The integration of liquid chromatography-mass spectrometry (LC-MS)-based chemical composition data with antiproliferative activity against three cancer cell lines-PC-3 (prostate adenocarcinoma), SiHa (cervical carcinoma), and A549 (lung carcinoma)-as well as a normal mouse fibroblast line (L929) was performed by covariate analysis. These compounds were subsequently isolated and structurally characterized using spectroscopic methods.

RESULTS

Through covariate statistics, seven m/z features were found to be plausible active compounds, and after isolation, they were related to butyrolactone and arylnaphthalide lignans. Among the active isolates, an unreported compound, (+)-phyllanlathyrin 6, was discovered in the aerial part of Phyllanthus lathyroides. The isolated compounds exhibited moderate to good antiproliferative activity (IC50 < 20 µM) with selectivity to SiHa, validating the covariate-based identification approach.

CONCLUSIONS

These findings highlight the potential of Phyllanthus species as sources of novel anticancer agents, with specific arylnaphthalide lignans showing promising cytotoxic effects that could be further developed into therapeutic leads. Additionally, this study underscores the value of combining advanced analytical techniques with bioactivity testing to uncover bioactive compounds from natural sources. The results contribute to the growing body of evidence supporting the therapeutic relevance of Phyllanthus species and provide a foundation for future drug development efforts targeting cancer treatment.

Therapeutic Potential of Plant-Derived Compounds and Plant Extracts in Rheumatoid Arthritis-Comprehensive Review

Rheumatoid arthritis (RA) is a persistent autoimmune disorder that is characterized by joint inflammation, discomfort, and impairment. Despite the existence of several therapeutic approaches, their effectiveness is often restricted and may be linked to unfavorable side effects. Consequently, there has been growing interest in investigating naturally derived compounds as plausible therapeutic agents for RA disease. The objective of this review is to summarize the existing preclinical and clinical evidence regarding the efficacy of naturally extracted compounds and plant extracts in the treatment of RA, focusing on their anti-inflammatory, anti-oxidative, and immunomodulatory properties. Some of the problems with using natural chemicals are the uneven quality of commercially available preparations and the poor bioavailability of these compounds. Future investigations should focus on improving the formulations, conducting thorough clinical trials, and exploring different techniques to fully utilize the intrinsic potential of naturally derived chemicals in treating RA.

Exploring the Comprehensive Neuroprotective and Anticancer Potential of Afzelin

Neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, Huntington's disease, and others) and cancer, seemingly disparate in their etiology and manifestation, exhibit intriguing associations in certain cellular and molecular processes. Both cancer and neurodegenerative diseases involve the deregulation of cellular processes such as apoptosis, proliferation, and DNA repair and pose a significant global health challenge. Afzelin (kaempferol 3-O-rhamnoside) is a flavonoid compound abundant in various plant sources. Afzelin exhibits a diverse range of biological activities, offering promising prospects for the treatment of diseases hallmarked by oxidative stress and deregulation of cell death pathways. Its protective potential against oxidative stress is also promising for alleviating the side effects of chemotherapy. This review explores the potential therapeutic implications of afzelin, including its capacity to mitigate oxidative stress, modulate inflammation, and promote cellular regeneration in neurodegenerative and cancer diseases.

SREBPs as the potential target for solving the polypharmacy dilemma

The phenomenon of polypharmacy is a common occurrence among older people with multiple health conditions due to the rapid increase in population aging and the popularization of clinical guidelines. The prevalence of metabolic syndrome is growing quickly, representing a serious threat to both the public and the worldwide healthcare systems. In addition, it enhances the risk of cardiovascular disease as well as mortality and morbidity. Sterol regulatory element binding proteins (SREBPs) are basic helix-loop-helix leucine zipper transcription factors that transcriptionally modulate genes that regulate lipid biosynthesis and uptake, thereby serving an essential role in biological systems regulation. In this article, we have described the structure of SREBPs and explored their activation and regulation of signals. We also reveal that SREBPs are intricately involved in the modulation of metabolic diseases and thus have tremendous potential as the novel target for single-drug therapy for multiple diseases.

Anti-Cancer Properties of Resveratrol: A Focus on Its Impact on Mitochondrial Functions

Cancer is one of the most serious public health issues worldwide, demanding ongoing efforts to find novel therapeutic agents and approaches. Amid growing interest in the oncological applications of phytochemicals, particularly polyphenols, resveratrol-a naturally occurring polyphenolic stilbene derivative-has emerged as a candidate of interest. This review analyzes the pleiotropic anti-cancer effects of resveratrol, including its modulation of apoptotic pathways, cell cycle regulation, inflammation, angiogenesis, and metastasis, its interaction with cancer stem cells and the tumor microenvironment. The effects of resveratrol on mitochondrial functions, which are crucial to cancer development, are also discussed. Future research directions are identified, including the elucidation of specific molecular targets, to facilitate the clinical translation of resveratrol in cancer prevention and therapy.

Emodin-8-O-Glucoside-Isolation and the Screening of the Anticancer Potential against the Nervous System Tumors

Emodin-8-O-glucoside (E-8-O-G) is a glycosylated derivative of emodin that exhibits numerous biological activities, including immunomodulatory, anti-inflammatory, antioxidant, hepatoprotective, or anticancer activities. However, there are no reports on the activity of E-8-O-G against cancers of the nervous system. Therefore, the aim of the study was to investigate the antiproliferative and cytotoxic effect of E-8-O-G in the SK-N-AS neuroblastoma, T98G human glioblastoma, and C6 mouse glioblastoma cancer cells. As a source of E-8-O-G the methanolic extract from the aerial parts of Reynoutria japonica Houtt. (Polygonaceae) was used. Thanks to the application of centrifugal partition chromatography (CPC) operated in the descending mode using a mixture of petroleum ether:ethyl acetate:methanol:water (4:5:4:5 v/v/v/v) and a subsequent purification with preparative HPLC, E-8-O-G was obtained in high purity in a sufficient quantity for the bioactivity tests. Assessment of the cancer cell viability and proliferation were performed with the MTT (3-(bromide 4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium), CTG (CellTiter-Glo®) and BrdU (5-bromo-2'-deoxyuridine) assays, respectively. E-8-O-G inhibits the viability and proliferation of SK-N-AS neuroblastoma, T98G human glioblastoma multiforme, and C6 mouse glioblastoma cells dose-dependently. E-8-O-G seems to be a promising natural antitumor compound in the therapy of nervous system tumors.

Tomatidine targets ATF4-dependent signaling and induces ferroptosis to limit pancreatic cancer progression

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with high metastasis and therapeutic resistance. Activating transcription factor 4 (ATF4), a master regulator of cellular stress, is exploited by cancer cells to survive. Prior research and data reported provide evidence that high ATF4 expression correlates with worse overall survival in PDAC. Tomatidine, a natural steroidal alkaloid, is associated with inhibition of ATF4 signaling in multiple diseases. Here, we discovered that in vitro and in vivo tomatidine treatment of PDAC cells inhibits tumor growth. Tomatidine inhibited nuclear translocation of ATF4 and reduced the transcriptional binding of ATF4 with downstream promoters. Tomatidine enhanced gemcitabine chemosensitivity in 3D ECM-hydrogels and in vivo. Tomatidine treatment was associated with induction of ferroptosis signaling validated by increased lipid peroxidation, mitochondrial biogenesis, and decreased GPX4 expression in PDAC cells. This study highlights a possible therapeutic approach utilizing a plant-derived metabolite, tomatidine, to target ATF4 activity in PDAC.

Caffeic Acid Phenethyl Ester (CAPE) Synergistically Enhances Paclitaxel Activity in Ovarian Cancer Cells

Caffeic acid phenethyl ester (CAPE) belongs to the phenols found in propolis. It has already shown strong antiproliferative, cytotoxic and pro-apoptotic activities against head and neck cancers and against breast, colorectal, lung and leukemia cancer cells. Ovarian cancer is one of the most dangerous gynecological cancers. Its treatment involves intensive chemotherapy with platinum salts and paclitaxel (PTX). The purpose of this study was to evaluate whether the combined use of CAPE and paclitaxel increases the effectiveness of chemotherapeutic agents. The experiment was performed on three ovarian cancer lines: OV7, HTB78, and CRL1572. The effect of the tested compounds was assessed using H-E staining, a wound-healing test, MTT and the cell death detection ELISAPLUS test. The experiment proved that very low doses of PTX (10 nM) showed a cytotoxic effect against all the cell lines tested. Also, the selected doses of CAPE had a cytotoxic effect on the tested ovarian cancer cells. An increase in the cytotoxic effect was observed in the OV7 line after the simultaneous administration of 10 nM PTX and 100 µM CAPE. The increase in the cytotoxicity was dependent on the CAPE dosage (50 vs. 100 µM) and on the duration of the experiment. In the other cell lines tested, the cytotoxic effect of PTX did not increase after the CAPE administration. The administration of PTX together with CAPE increased the percentage of apoptotic cells in the tested ovarian cancer cell lines. Moreover, the simultaneous administration of PTX and CAPE enhanced the anti-migration activity of the chemotherapeutic used in this study.