Cytotoxic effect of selected wild orchids on two different human cancer cell lines

1,5,6-Trimethoxy-2,7-dihydroxyphenanthrene from Dendrobium officinale Exhibited Antitumor Activities for HeLa Cells

Natural products are irreplaceable reservoirs for cancer treatments. In this study, 12 phenanthrene compounds were extracted and isolated from Dendrobium officinale. Each chemical structure was identified using comprehensive NMR analysis. All compounds were evaluated for their cytotoxic activities against five tumor cell lines, i.e., HeLa, MCF-7, SK-N-AS, Capan-2 and Hep G2. Compound 5, 1,5,6-trimethoxy-2,7-dihydroxyphenanthrene, displayed the most significant cytotoxic effect against HeLa and Hep G2 cells, with an IC50 of 0.42 and 0.20 μM. For Hela cells, further experiments demonstrated that compound 5 could obviously inhibit cell migration, block cell cycle in the G0/G1 phase and induce apoptosis. Expression measurements for p53 indicated that knock down of p53 by siRNA could mitigate the apoptosis induced by compound 5. Therefore, the compound 5 is a potential candidate drug for HeLa cells in cervical cancer.

Antiproliferative activity of antimicrobial peptides and bioactive compounds from the mangrove Glutamicibacter mysorens

The Glutamicibacter group of microbes is known for antibiotic and enzyme production. Antibiotics and enzymes produced by them are important in the control, protection, and treatment of chronic human diseases. In this study, the Glutamicibacter mysorens (G. mysorens) strain MW647910.1 was isolated from mangrove soil in the Mangalore region of India. After optimization of growth conditions for G. mysorens on starch casein agar media, the micromorphology of G. mysorens was found to be spirally coiled spore chain, each spore visualized as an elongated cylindrical hairy appearance with curved edges visualized through Field Emission Scanning Electron Microscopy (FESEM) analysis. The culture phenotype with filamentous mycelia, brown pigmentation, and ash-colored spore production was observed. The intracellular extract of G. mysorens characterized through GCMS analysis detected bioactive compounds reported for pharmacological applications. The majority of bioactive compounds identified in intracellular extract when compared to the NIST library revealed molecular weight ranging below 1kgmole^-1. The Sephadex G-10 could result in 10.66 fold purification and eluted peak protein fraction showed significant anticancer activity on the prostate cancer cell line. Liquid Chromatography-Mass Spectrometry (LC-MS) analysis revealed Kinetin-9-ribose and Embinin with a molecular weight below 1 kDa. This study showed small molecular weight bioactive compounds produced from microbial origin possess dual roles, acting as antimicrobial peptides (AMPs) and anticancer peptides (ACPs). Hence, the bioactive compounds produced from microbial origin are a promising source of future therapeutics.

Phytochemicals from Vanda bensonii and Their Bioactivities to Inhibit Growth and Metastasis of Non-Small Cell Lung Cancer Cells

The most prevalent lung cancer is non-small cell lung cancer (NSCLC). This lung cancer type often develops other organ-specific metastases that are critical burdens in the treatment process. Orchid species in the genus Vanda have shown their potential in folkloric medication of diverse diseases but not all its species have been investigated, and little is known about their anticancer activities against NSCLC. Here, we firstly profiled the specialized metabolites of Vanda bensonii and examined their capability to inhibit growth and metastasis of NSCLC using NCI-H460 cells as a study model. Four phytochemicals, including phloretic acid methyl ester (1), cymbinodin-A (2), ephemeranthoquinone B (3), and protocatechuic acid (4), were isolated from the whole plant methanolic extract of V. bensonii. The most distinguished cytotoxic effect on NCI-H460 cells was observed in the treatments with crude methanolic extract and compound 2 with the half maximal inhibitory concentrations of 40.39 μg mL−1 and 50.82 μM, respectively. At non-cytotoxic doses (10 μg mL−1 or 10 μM), only compound 1 could significantly limit NCI-H460 cell proliferation when treated for 48 h, while others excluding compound 4 showed significant reduction in cell proliferation after treating for 72 h. Compound 1 also significantly decreased the migration rate of NCI-H460 cells examined through a wound-healing assay. Additionally, the crude extract and compound 1 strongly affected survival and growth of NCI-H460 cells under anchorage-independent conditions. Our findings proved that natural products from V. bensonii could be promising candidates for the future pharmacotherapy of NSCLC.

Orchidaceae-Derived Anticancer Agents: A Review

Simple Summary

Orchids are commonly used in folk medicine for the treatment of infections and tumors but little is known about the actual chemical composition of these plants and their anticancer properties. In this paper, the most recent literature on orchid-derived bioactive substances with anticancer properties is reviewed. According to the published data, numerous species of orchids contain potential antitumor chemicals. Still, a relatively insignificant number of species of orchids have been tested for their bioactive properties and most of those studies were on Asian taxa. Broader research, ’including American and African species, as well as the correct identification of samples, is essential for evaluating the usefulness of orchids as a plant family with huge anticancer potential.

Abstract

Species of orchids, which belong to the largest family of flowering plants, are commonly used in folk medicine for the treatment of infections and tumors. However, little is known about the actual chemical composition of these plants and their anticancer properties. In this paper, the most recent literature on orchid-derived bioactive substances with anticancer properties is reviewed. For the assessment, previous papers on the anticancer activity of Orchidaceae published since 2015 were considered. The papers were found by exploring electronic databases. According to the available data, many species of orchids contain potential antitumor chemicals. The bioactive substances in a relatively insignificant number of orchids are identified, and most studies are on Asian taxa. Broader research on American and African species and the correct identification of samples included in the experiments are essential for evaluating the usefulness of orchids as a plant family with vast anticancer potential.

Dihydrophenanthrenes from a Sicilian Accession of Himantoglossum robertianum (Loisel.) P. Delforge Showed Antioxidant, Antimicrobial, and Antiproliferative Activities

The peculiar aspect that emerges from the study of Orchidaceae is the presence of various molecules, which are particularly interesting for pharmaceutical chemistry due to their wide range of biological resources. The aim of our study was to investigate the properties of two dihydrophenanthrenes, isolated, for the first time, from Himantoglossum robertianum (Loisel.) P. Delforge (Orchidaceae) bulbs and roots. Chemical and spectroscopic study of the bulbs and roots of Himantoglossumrobertianum (Loisel.) P. Delforge resulted in the isolation of two known dihydrophenanthrenes-loroglossol and hircinol-never isolated from this plant species. The structures were evaluated based on ¹H-NMR, ¹³C-NMR, and two-dimensional spectra, and by comparison with the literature. These two molecules have been tested for their possible antioxidant, antimicrobial, antiproliferative, and proapoptotic activities. In particular, it has been shown that these molecules cause an increase in the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) in polymorphonuclear leukocytes (PMN); show antimicrobial activity against Escherichia coli and Staphylococcus aureus, and have anti-proliferative effects on gastric cancer cell lines, inducing apoptosis effects. Therefore, these two molecules could be considered promising candidates for pharmaceutical and nutraceutical preparations.

A pharmacognostic approach for mitigating pancreatic cancer: emphasis on herbal extracts and phytoconstituents

Background

Pancreatic cancer is studied as one of the most lethal cancers with currently no control of its lethality, mainly due to its late diagnosis and lack of foolproof treatment processes. Despite continuous efforts being made in looking for therapies to deal with cancer, it keeps on being a labyrinth for the researchers. Efforts like discovering new treatment options, repurposing existing drugs, are continuously made to deal with this cancer.

Main body

With the urge to get answers and the fact that nature has all roots of therapeutics, efforts are made in the direction of finding those answers for providing ministrations for pancreatic cancer from plant products. Plant products are used as treatment options either directly in the form of extracts or an alternative to them is individual phytochemicals that are either isolated from the plants or are commercially synthesized for various purposes. In this review, we put forward such pharmacognostic initiatives made in combating pancreatic cancer, focusing mainly on plant extracts and various phytochemicals; along with the mechanisms which they triggered to fulfill the need for cytotoxicity to pancreatic cancer cells (in vitro and in vivo).

Conclusion

This study will thus provide insights into new combination therapy that can be used and also give a clue on which plant product and phytoconstituent can be used in dealing with pancreatic cancer.

Graphical abstract

Comparative Cytotoxic Activity of Wild Harvested Stems and In Vitro-Raised Protocorms of Dendrobium chryseum Rolfe in Human Cervical Carcinoma and Glioblastoma Cell Lines

From the medicinal orchid Dendrobium chryseum Rolfe, which is used in traditional and folk Chinese medicine, the protocorms were raised in Murashige and Skoog (MS) media in three strengths, full strength (FMS), half strength (1/2 MS), and quarter strength (1/4 MS), with or without the phytohormones 6-benzylaminopurine (BAP) and 1-naphthaleneacetic acid (NAA) and coconut water (CW). The comparative cytotoxic activities of the wild and in vitro-raised protocorms were evaluated in human cervical carcinoma (HeLa) and human glioblastoma (U251) cell lines by MTT assay. In in vivo and in vitro, the methanol extracts of D. chryseum showed significant cytotoxic activities. Significant growth inhibition (%) and potent IC₅₀ values were demonstrated in HeLa cell lines (49.79% (210.5 μg/mL) for in vitro-raised Dendrobium chryseum (DCT) versus 46.97% (226.5 μg/mL) for wild Dendrobium chryseum (DCW)). Similarly, activities against U251 cell lines exhibited also significant inhibition (28.76% (612.54 μg/mL) for DCW and 17.15% (1059.92 μg/mL) for DCT). The cytotoxic activities of both, wild and tissue-cultured samples, were superior in HeLa cells. In U251 cells, the wild sample was more active than the tissue-cultured one with a moderate cytotoxic effect. Hence, protocorm culture may therefore be a promising future tool for producing pharmacologically bioactive compounds in medicinal orchids. Such sustainable technology approach will minimize the pressure on the natural population of threatened but commercially important medicinal orchids.