Pro-apoptotic and anti-adhesive effects of four African plant extracts on the breast cancer cell line MCF-7

Contribution of Sub-Saharan African medicinal plants to cancer research: Scientific basis 2013-2023

Cancer incidence and mortality rates are increasing worldwide. Cancer treatment remains a real challenge for African countries, especially in sub-Saharan Africa where funding and resources are very limited. High costs, side effects and drug resistance associated with cancer treatment have encouraged scientists to invest in research into new herbal cancer drugs. In order to identify potential anticancer plants for drug development, this review aims to collect and summarize anticancer activities (in vitro/in vivo) and molecular mechanisms of sub-Saharan African medicinal plant extracts against cancer cell lines. Scientific databases such as ScienceDirect, Google Scholar and PubMed were used to search for research articles published from January 2013 to May 2023 on anticancer medicinal plants in sub-Saharan Africa. The data were analyzed to highlight the cytotoxicity and molecular mechanisms of action of these listed plants. A total of 85 research papers covering 204 medicinal plant species were selected for this review. These plants come from 57 families, the most dominant being the plants of the family Amaryllidaceae (16), Fabaceae (14), Annonaceae (10), Asteraceae (10). Plant extracts exert their anticancer activity mainly by inducing apoptosis and stopping the cell cycle of cancer cells. Several plant extracts from sub-Saharan Africa therefore have strong potential for the search for original anticancer phytochemicals. Chemoproteomics, multi-omics, genetic editing technology (CRISPR/Cas9), combined therapies and artificial intelligence tools are cutting edge emerging technologies that facilitate the discovery and structural understanding of anticancer molecules of medicinal plants, reveal their direct targets, explore their therapeutic uses and molecular bases.

Natural products derived from medicinal plants and microbes might act as a game-changer in breast cancer: a comprehensive review of preclinical and clinical studies

Breast cancer (BC) is the most prevalent neoplasm among women. Genetic and environmental factors lead to BC development and on this basis, several preventive - screening and therapeutic interventions have been developed. Hormones, both in the form of endogenous hormonal signaling or hormonal contraceptives, play an important role in BC pathogenesis and progression. On top of these, breast microbiota includes both species with an immunomodulatory activity enhancing the host's response against cancer cells and species producing proinflammatory cytokines associated with BC development. Identification of novel multitargeted therapeutic agents with poly-pharmacological potential is a dire need to combat advanced and metastatic BC. A growing body of research has emphasized the potential of natural compounds derived from medicinal plants and microbial species as complementary BC treatment regimens, including dietary supplements and probiotics. In particular, extracts from plants such as Artemisia monosperma Delile, Origanum dayi Post, Urtica membranacea Poir. ex Savigny, Krameria lappacea (Dombey) Burdet & B.B. Simpson and metabolites extracted from microbes such as Deinococcus radiodurans and Streptomycetes strains as well as probiotics like Bacillus coagulans and Lactobacillus brevis MK05 have exhibited antitumor effects in the form of antiproliferative and cytotoxic activity, increase in tumors' chemosensitivity, antioxidant activity and modulation of BC - associated molecular pathways. Further, bioactive compounds like 3,3'-diindolylmethane, epigallocatechin gallate, genistein, rutin, resveratrol, lycopene, sulforaphane, silibinin, rosmarinic acid, and shikonin are of special interest for the researchers and clinicians because these natural agents have multimodal action and act via multiple ways in managing the BC and most of these agents are regularly available in our food and fruit diets. Evidence from clinical trials suggests that such products had major potential in enhancing the effectiveness of conventional antitumor agents and decreasing their side effects. We here provide a comprehensive review of the therapeutic effects and mechanistic underpinnings of medicinal plants and microbial metabolites in BC management. The future perspectives on the translation of these findings to the personalized treatment of BC are provided and discussed.

Anoikis resistance--protagonists of breast cancer cells survive and metastasize after ECM detachment

Breast cancer exhibits the highest global incidence among all tumor types. Regardless of the type of breast cancer, metastasis is a crucial cause of poor prognosis. Anoikis, a form of apoptosis initiated by cell detachment from the native environment, is an outside-in process commencing with the disruption of cytosolic connectors such as integrin-ECM and cadherin-cell. This disruption subsequently leads to intracellular cytoskeletal and signaling pathway alterations, ultimately activating caspases and initiating programmed cell death. Development of an anoikis-resistant phenotype is a critical initial step in tumor metastasis. Breast cancer employs a series of stromal alterations to suppress anoikis in cancer cells. Comprehensive investigation of anoikis resistance mechanisms can inform strategies for preventing and regressing metastatic breast cancer. The present review first outlines the physiological mechanisms of anoikis, elucidating the alterations in signaling pathways, cytoskeleton, and protein targets that transpire from the outside in upon adhesion loss in normal breast cells. The specific anoikis resistance mechanisms induced by pathological changes in various spatial structures during breast cancer development are also discussed. Additionally, the genetic loci of targets altered in the development of anoikis resistance in breast cancer, are summarized. Finally, the micro-RNAs and targeted drugs reported in the literature concerning anoikis are compiled, with keratocin being the most functionally comprehensive. Video Abstract.

Icacinaceae Plant Family: A Recapitulation of the Ethnobotanical, Phytochemical, Pharmacological, and Biotechnological Aspects

Icacinaceae, an Angiospermic family comprising 35 genera and 212 accepted species, including trees, shrubs, and lianas with pantropical distribution, is one of the most outshining yet least explored plant families, which despite its vital role as a source of pharmaceuticals and nutraceuticals has received a meagre amount of attraction from the scientific community. Interestingly, Icacinaceae is considered a potential alternative resource for camptothecin and its derivatives, which are used in treating ovarian and metastatic colorectal cancer. However, the concept of this family has been revised many times, but further recognition is still needed. The prime objective of this review is to compile the available information on this family in order to popularize it in the scientific community and the general population and promote extensive exploration of these taxa. The phytochemical preparations or isolated compounds from the Icacinaceae family have been centrally amalgamated to draw diverse future prospects from this inclusive plant species. The ethnopharmacological activities and the associated endophytes and cell culture techniques are also depicted. Nevertheless, the methodical evaluation of the Icacinaceae family is the only means to preserve and corroborate the folkloristic remedial effects and provide scientific recognition of its potencies before they are lost under the blanket of modernization.

Fabrication of a microfluidic device for probiotic drug's dosage screening: Precision Medicine for Breast Cancer Treatment

Breast cancer is the most common cancer in women; it has been affecting the lives of millions each year globally and microfluidic devices seem to be a promising method for the future advancements in this field. This research uses a dynamic cell culture condition in a microfluidic concentration gradient device, helping us to assess breast anticancer activities of probiotic strains against MCF-7 cells. It has been shown that MCF-7 cells could grow and proliferate for at least 24 h; however, a specific concentration of probiotic supernatant could induce more cell death signaling population after 48 h. One of our key findings was that our evaluated optimum dose (7.8 mg/L) was less than the conventional static cell culture treatment dose (12 mg/L). To determine the most effective dose over time and the percentage of apoptosis versus necrosis, flowcytometric assessment was performed. Exposing the MCF-7 cells to probiotic supernatant after 6, 24 and 48 h, confirmed that the apoptotic and necrotic cell death signaling were concentration and time dependent. We have shown a case that these types of microfluidics platforms performing dynamic cell culture could be beneficial in personalized medicine and cancer therapy.

Cancer and apoptosis: The apoptotic activity of plant and marine natural products and their potential as targeted cancer therapeutics

Cancer is a multifactorial, multi-stage disease, including complex cascades of signaling pathways—the cell growth governed by dysregulated and abrupt cell division. Due to the complexity and multi-regulatory cancer progression, cancer is still a challenging disease to treat and survive. The screening of extracts and fractions from plants and marine species might lead to the discovery of more effective compounds for cancer therapeutics. The isolated compounds and reformed analogs were known as future prospective contenders for anti-cancer chemotherapy. For example, Taxol, a potent mitotic inhibitor discovered from Taxus brevifolia, suppresses cell growth and arrest, induces apoptosis, and inhibits proliferation. Similarly, marine sponges show remarkable tumor chemo preventive and chemotherapeutic potential. However, there is limited research to date. Several plants and marine-derived anti-cancer compounds having the property to induce apoptosis have been approved for clinical trials. The anti-cancer activity kills the cell and slows the growth of cancer cells. Among cell death mechanisms, apoptosis induction is a more profound mechanism of cell death triggered by naturally isolated anti-cancer agents. Evading apoptosis is the major hurdle in killing cancer cells, a mechanism mainly regulated as intrinsic and extrinsic. However, it is possible to modify the apoptosis-resistant phenotype of the cell by altering many of these mechanisms. Various extracts and fractions successfully induce apoptosis, cell-cycle modulation, apoptosis, and anti-proliferative activity. Therefore, there is a pressing need to develop new anti-cancer drugs of natural origins to reduce the effects on normal cells. Here, we’ve emphasized the most critical elements: i) A better understanding of cancer progression and development and its origins, ii) Molecular strategies to inhibit the cell proliferation/Carcino-genesis, iii) Critical regulators of cancer cell proliferation and development, iv) Signaling Pathways in Apoptosis: Potential Targets for targeted therapeutics, v) Why Apoptosis induction is mandatory for effective chemotherapy, vi) Plants extracts/fractions as potential apoptotic inducers, vii) Marine extracts as Apoptotic inducers, viii) Marine isolated Targeted compounds as Apoptotic inducers (FDA Approved/treatment Phase). This study provides a potential therapeutic option for cancer, although more clinical studies are needed to verify its efficacy in cancer chemotherapy.

Anticancer properties of medicinal plants and their bioactive compounds against breast cancer: a review on recent investigations

Breast cancer (BC) is one of the most common and recurring diseases and the second leading cause of death in women. Despite prevention, diagnostics, and therapeutic options such as radiation therapy and chemotherapy, the number of occurrences increases every year. Therefore, novel therapeutic drugs targeting specifically different checkpoints should be developed against breast cancer. Among drugs that can be developed to treat breast cancer, natural products, such as plant-derived compounds, showed significant anti-breast cancer properties. These substances belong to different chemical classes such as flavonoids, terpenoids, phenolic acids, and alkaloids. They exert their in vitro and in vivo cytotoxic activities against breast cancer cell lines via different mechanisms, including the inhibition of extrinsic and intrinsic apoptotic pathways, the arrest of the cell cycle, and the activation of autophagy. Moreover, they also exhibit anti-angiogenesis and antimetastatic action. Moreover, chemoprevention effects of these bioactive compounds were signaled only for certain drugs. Therefore, the aim of this review is to highlight the pharmacological actions of medicinal plants and their bioactive compounds on breast cancer. Moreover, the role of these substances in breast cancer chemoprevention was also discussed.

Breast Cancer: A Global Concern, Diagnostic and Therapeutic Perspectives, Mechanistic Targets in Drug Development

Cancer is a complex multifactorial process, unchecked and abrupt division, and cell growth—conventional chemotherapy, along with radiotherapy, is used to treat breast cancer. Due to reduce efficacy and less survival rate, there is a particular need for the discovery of new active anticancer agents. Natural resources such as terrestrial/marine plants or organisms are a promising source for the generation of new therapeutics with improving efficacy. The screening of natural plant extracts and fractions, isolations of phytochemicals, and mechanistic study of those potential compounds play a remarkable role in the development of new therapeutic drugs with increased efficacy. Cancer is a multistage disease with complex signaling cascades. The initial study of screening whole extracts or fractions and later the isolation of secondary compounds and their mechanism of action study gives a clue of potential therapeutic agents for future drug development. The phytochemicals present in extracts/fractions produce remarkable effects due to synergistically targeting multiple signals. In this review, the molecular targets of extracts/ fractions and isolated compounds highlighted. The therapeutic agent's mechanistic targets in drug development focused involves; i) Induction of Apoptosis, ii) modulating cell cycle arrest, iii) Inhibition or suppression of invasion and metastasis and iv) various other pro-survival signaling pathways. The phytochemicals and their modified analogs identified as future potential candidates for anticancer chemotherapy.

Jaceosidin: A Natural Flavone with Versatile Pharmacological and Biological Activities

Nature always remains an inexhaustible source of treasures for mankind. It remains a mystery for every challenge until the completion of the challenge. While we talk about the complicated health issues, nature offers us a great variety of chemical scaffolds and their various moieties packed in the form of natural products e.g., plants, microorganisms (fungi, algae, protozoa), and terrestrial vertebrates and invertebrates. This review article is an update about jaceosidin, a bioactive flavone, from genus Artemisia. This potentially active compound exhibits a variety of pharmacological activities including anti-inflammatory, anti-oxidant, anti-bacterial, antiallergic and anti-cancer activities. The bioactivities and the therapeutic action of jaceosidin, especially the modulation of different cell signaling pathways (ERK1/2, NF-κB, PI3K/Akt and ATM-Chk1/2) which become deregulated in various pathological disorders, have been focused here. The reported data suggest that the bioavailability of this anti-cancer compound should be enhanced by utilizing various chemical, biological and computational techniques. Moreover, it is recommended that researchers and scientists should work on exploring the mode of action of this particular flavone to precede it further as a potent anti-cancer compound.

Effects of extracts and molecules derived from medicinal plants of West Africa in the prevention and treatment of gynecological cancers. A Review

Medicinal plants are a potential source of drug discovery and development of new pharmacological compounds for cancer chemoprevention. More than 80% of the West African population uses medicinal plants. It is estimated that over 60% of approved anti-cancer agents are derived from plants. The plant raw material used in African traditional medicine and particularly in West Africa can be an important source for the research of anti-tumor drugs against gynecological cancers. These tumors have a negative impact on women's general health status and causes enormous health costs as they affect all age groups. Gynecological cancers remain thus a major concern worldwide, especially in West Africa where these cancers are the leading cause of cancer deaths in women. This review reports on the contribution of West African flora to the discovery of potential antiproliferative and/or cytotoxic phytochemical compounds against gynecological cancer cells. Scientific databases such as PubMed, ScienceDirect, Scopus and GoogleScholar were used to extract publications reporting West African plants and/or isolated compounds used in cell models of gynecological cancers. Thresholds of cytotoxicity and modes of action of these phytochemicals have been summarized. This research can serve as a basis for taking medicinal plants into account in the management of these gynecological cancers in resource-limited countries such as those in West Africa.

Potential Mechanisms Involved in the Anticonvulsant Effect of Methanol Extract of Pyrenancantha staudtii in Mice

OBJECTIVE

To determine the potential effect of Pyrenancantha staudtii extract on experimentally induced seizures in mice and to evaluate the role of benzodiazepines, naloxone, and serotonin within these pathways.

METHODS

Animal behaviours were evaluated using open field, hexobarbitone-induced sleep model, and anticonvulsant activity using picrotoxin-, or strychnine-, or isoniazid-induced convulsions. Attempt to understand the mode of action of the anticonvulsant activity of the plant, three notable antagonists (flumazenil, 3 mg/kg; naloxone 5 mg/kg, i.p., and cyproheptadine, 4 mg/kg, i.p) were used.

RESULTS

The results revealed a significant (p < 0.05) reduction in the frequency of rearing and grooming episodes compared with the control. The extract of P. staudtii potentiates the sleeping time of hexobarbitone-induced hypnosis in a dose-related manner. P. staudtii stem bark extracts significantly (p<0.05) prolonged the onset of a seizure and attenuated the duration of seizure in a dose-dependent manner in picrotoxin- and or isoniazid-induced seizures. While, P. staudtii stem bark extract at all doses (100, 200, and 400 mg kg-1) though significantly prolonged the onset of action, but did not confer any significant changes on the duration, as well as mortality in this strychnine-induced seizure model. However, the anticonvulsant activity of the methanolic extract of P. staudtii was significantly reversed following intraperitoneal pre-treatment with flumazenil (GABA receptor antagonist) and naloxone (opioid receptor antagonist) but not cyproheptadine (5-HT2 receptor antagonist) in picrotoxin-induced convulsion.

CONCLUSION

The data obtained suggest that methanol extract of P. staudtii possessed significant anticonvulsant effect, thereby confirming the traditional uses of P. staudtii in the treatment of epilepsy; mechanisms of which could involve the interaction with GABAergic and or opioidergic system.

GCSH antisense regulation determines breast cancer cells' viability

Since it is known that cancer cells exhibit a preference for increased glycine consumption, the respective glycine metabolizing enzymes are in focus of many research projects. However, no cancer associated studies are available for the Glycine Cleavage System Protein H (GCSH) to date. Our initial analysis revealed a GCSH-overexpression of the protein-coding transcript variant 1 (Tv1) in breast cancer cells and tissue. Furthermore, a shorter (391 bp) transcript variant (Tv*) was amplified with an increased expression in healthy breast cells and a decreased expression in breast cancer samples. The Tv1/Tv* transcript ratio is 1.0 in healthy cells on average, and between 5–10 in breast cancer cells. Thus, a GCSH-equilibrium at the transcript level is likely conceivable for optimal glycine degradation. A possible regulative role of Tv* was proven by Tv1-Tv*-RNA-binding and overexpression studies which consequently led to serious physiological alterations: decreased metabolic activity, release of the lactate dehydrogenase, increased extracellular acidification, and finally necrosis as a result of impaired plasma membranes. In contrast, Tv1-overexpression led to an additional increase in cellular vitality of the tumor cells, primarily due to the acceleration of the mitochondrial glycine decarboxylation activity. Ultimately, we provide the first evidence of a sensitive GCSH-antisense regulation which determines cancerous cell viability.

What Has Come out from Phytomedicines and Herbal Edibles for the Treatment of Cancer?

Several modern treatment strategies have been adopted to combat cancer with the aim of minimizing toxicity. Medicinal plant-based compounds with the potential to treat cancer have been widely studied in preclinical research and have elicited many innovations in cutting-edge clinical research. In parallel, researchers have eagerly tried to decrease the toxicity of current chemotherapeutic agents either by combining them with herbals or in using herbals alone. The aim of this article is to present an update of medicinal plants and their bioactive compounds, or mere changes in the bioactive compounds, along with herbal edibles, which display efficacy against diverse cancer cells and in anticancer therapy. It describes the basic mechanism(s) of action of phytochemicals used either alone or in combination therapy with other phytochemicals or herbal edibles. This review also highlights the remarkable synergistic effects that arise between certain herbals and chemotherapeutic agents used in oncology. The anticancer phytochemicals used in clinical research are also described; furthermore, we discuss our own experience related to semisynthetic derivatives, which are developed based on phytochemicals. Overall, this compilation is intended to facilitate research and development projects on phytopharmaceuticals for successful anticancer drug discovery.

Acute toxicity studies of the South African medicinal plant Galenia africana

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G. africana LD₅₀ was over 2000 mg/kgbw for acute oral and dermal toxicity studies.

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G. africana was non-irritant on the reconstituted human epidermis models.

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Open application of extract at various concentrations did not result in a SI of ≥ 3.

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G. africana did not elicit a hypersensitivity response.

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G. africana can be used in the pharmaceutical and cosmetic industries.

Background

Medicinal plants are used by a large proportion of the global population as complementary and alternative medicines. However, little is known about their toxicity. G. africana has been used to treat wounds, coughs and skin diseases and is used in cosmetic formulations such as lotions and shampoos.

Methods

The acute oral and dermal toxicity potential of G. africana was analyzed after a single administration of 300 and 2000 mg/kgbw for acute oral toxicity and 2000 mg/kgbw for acute dermal toxicity. Female Sprague-Dawley rats were used for the acute oral toxicity study whereas both male and female Sprague-Dawley rats were used for the acute dermal toxicity study. In the Episkin skin irritation test, the irritation potential of G. africana (concentrate) and G. africana (in-use dilution) extracts were assessed using the Episkin reconstituted human epidermis. In the dermal sensitization study, female CBA/Ca mice were treated with G. africana concentrations of 50, 100 and 200 mg/ml respectively. The vehicle of choice was dimethylformamide which acted as a control.

Results

The results of the acute oral and dermal toxicity studies revealed that the median lethal dosage (LD₅₀) for G. africana extract in Sprague-Dawley rats was considered to exceed 2000 mg/kgbw. In the irritation test, the G. africana (concentrate) and G. africana (in-use dilution) extracts were non-irritant on the Episkin reconstituted human epidermis. In the dermal sensitization study, the stimulation index (SI) values for the mice treated with the G. africana extract at concentrations of 50, 100 and 200 mg/ml/kgbw, when compared to the control group, were 1.3, 0.9 and 1.3 respectively. The open application of the extract at the various concentrations did not result in a SI of ≥ 3 in any group. Hence, it did not elicit a hypersensitivity response.

Conclusion

These findings demonstrate that the acute toxicity profile for G. africana is acceptable and can subsequently be used for single use in the pharmaceutical and cosmetic industries.

First evidence of SGPL1 expression in the cell membrane silencing the extracellular S1P siren in mammary epithelial cells

The bioactive lipid sphingosine-1-phosphate (S1P) is a main regulator of cell survival, proliferation, motility, and platelet aggregation, and it is essential for angiogenesis and lymphocyte trafficking. In that S1P acts as a second messenger intra- and extracellularly, it might promote cancer progression. The main cause is found in the high S1P concentration in the blood, which encourage cancer cells to migrate through the endothelial barrier into the blood vessels. The irreversible degradation of S1P is solely caused by the sphingosine-1-phosphate lyase (SGPL1). SGPL1 overexpression reduces cancer cell migration and therefore silences the endogenous S1P siren, which promotes cancer cell attraction-the main reason for metastasis. Since our previous metabolomics studies revealed an increased SGPL1 activity in association with successful breast cancer cell treatment in vitro, we further investigated expression and localization of SGPL1. Expression analyses confirmed a very low SGPL1 expression in all breast cancer samples, regardless of their subtype. Additionally, we were able to prove a novel SGPL expression in the cytoplasm membrane of non-tumorigenic breast cells by fusing three independent methods. The general SGPL1 downregulation and the loss of the plasma membrane expression resulted in S1P dependent stimulation of migration in the breast cancer cell lines MCF-7 and BT-20. Not only S1P stimulated migration could be repressed by overexpressing the natural SGPL1 variant not but also more general migratory activity was significantly reduced. Here, for the first time, we report on the SGPL1 plasma membrane location in human, non-malignant breast epithelial cell lines silencing the extracellular S1P siren in vitro, and thereby regulating pivotal cellular functions. Loss of this plasma membrane distribution as well as low SGPL1 expression levels could be a potential prognostic marker and a viable target for therapy. Therefore, the precise role of SGPL1 for cancer treatment should be evaluated.

Fraxinus: A Plant with Versatile Pharmacological and Biological Activities

Fraxinus, a member of the Oleaceae family, commonly known as ash tree is found in northeast Asia, north America, east and western France, China, northern areas of Pakistan, India, and Afghanistan. Chemical constituents of Fraxinus plant include various secoiridoids, phenylethanoids, flavonoids, coumarins, and lignans; therefore, it is considered as a plant with versatile biological and pharmacological activities. Its tremendous range of pharmacotherapeutic properties has been well documented including anticancer, anti-inflammatory, antioxidant, antimicrobial, and neuroprotective. In addition, its bioactive phytochemicals and secondary metabolites can be effectively used in cosmetic industry and as a competent antiaging agent. Fraxinus presents pharmacological effectiveness by targeting the novel targets in several pathological conditions, which provide a spacious therapeutic time window. Our aim is to update the scientific research community with recent endeavors with specifically highlighting the mechanism of action in different diseases. This potentially efficacious pharmacological drug candidate should be used for new drug discovery in future. This review suggests that this plant has extremely important medicinal utilization but further supporting studies and scientific experimentations are mandatory to determine its specific intracellular targets and site of action to completely figure out its pharmacological applications.

Pinocembrin enriched fraction of Elytranthe parasitica (L.) Danser induces apoptosis in HCT 116 colorectal cancer cells

BACKGROUND

Colorectal cancer (CRC) is a highly predominant malignancy affecting millions worldwide. Plants belonging to Loranthaceae family have remarkable chemopreventive properties.

OBJECTIVE

The goal of the present study was to assess the antiproliferative and apoptosis-inducing effects of stem parts of Elytranthe parasitica (L.) Danser (EP) on colorectal cancer and identify the bioactive phytochemicals.

MATERIAL AND METHODS

EP methanol extract (EP.M) and its subsequent fractions were screened for antiproliferative activity in human colorectal carcinoma HCT 116 cell line. Phytocomposition of the bioactive fraction was analyzed by GC-MS. Further, apoptotic induction and cell cycle arrest was assessed in the most bioactive fractions.

RESULTS

EP.DEE (Diethyl Ether) fraction and a subsequent fraction derived by column chromatography, Fraction 3A (FR 3A) significantly inhibited the proliferation of HCT 116 cells (P < 0.05). FR 3A triggered apoptosis and notably modulated the cell cycle checkpoints. GC-MS analysis of FR 3A revealed the presence of 24 phytochemicals, the most prominent of which was pinocembrin (70.67%), a flavonoid.

CONCLUSION

Hence, it could be speculated that pinocembrin and its related derivatives may be the chief phytochemicals involved in apoptosis - mediated cytotoxicity of the enriched fraction. Our findings indicate the enriched fraction is a promising candidate which could be developed into a natural chemotherapeutic product for colorectal cancer therapy.

Synergistic Action of Genistein and Calcitriol in Immature Osteosarcoma MG-63 Cells by SGPL1 Up-Regulation

Background

Phytoestrogens such as genistein, the most prominent isoflavone from soy, show concentration-dependent anti-estrogenic or estrogenic effects. High genistein concentrations (>10 μM) also promote proliferation of bone cancer cells in vitro. On the other hand, the most active component of the vitamin D family, calcitriol, has been shown to be tumor protective in vitro and in vivo. The purpose of this study was to examine a putative synergism of genistein and calcitriol in two osteosarcoma cell lines MG-63 (early osteoblast), Saos-2 (mature osteoblast) and primary osteoblasts.

Methods

Thus, an initial screening based on cell cycle phase alterations, estrogen (ER) and vitamin D receptor (VDR) expression, live cell metabolic monitoring, and metabolomics were performed.

Results

Exposure to the combination of 100 μM genistein and 10 nM calcitriol reduced the number of proliferative cells to control levels, increased ERß and VDR expression, and reduced extracellular acidification (40%) as well as respiratory activity (70%), primarily in MG-63 cells. In order to identify the underlying cellular mechanisms in the MG-63 cell line, metabolic profiling via GC/MS technology was conducted. Combined treatment significantly influenced lipids and amino acids preferably, whereas metabolites of the energy metabolism were not altered. The comparative analysis of the log2-ratios revealed that after combined treatment only the metabolite ethanolamine was highly up-regulated. This is the result: a strong overexpression (350%) of the enzyme sphingosine-1-phosphate lyase (SGPL1), which irreversibly degrades sphingosine-1-phosphate (S1P), thereby, generating ethanolamine. S1P production and secretion is associated with an increased capability of migration and invasion of cancer cells.

Conclusion

From these results can be concluded that the tumor promoting effect of high concentrations of genistein in immature osteosarcoma cells is reduced by the co-administration of calcitriol, primarily by the breakdown of S1P. It should be tested whether this anti-metastatic pathway can be stimulated by combined treatment also in metastatic xenograft mice models.

Antitumor evaluation of two selected Pakistani plant extracts on human bone and breast cancer cell lines

BACKGROUND

The medicinal plants Vincetoxicum arnottianum (VSM), Berberis orthobotrys (BORM), Onosma hispida (OHRM and OHAM) and Caccinia macranthera (CMM) are used traditionally in Pakistan and around the world for the treatment of various diseases including cancer, dermal infections, uterine tumor, wounds etc. The present study focuses on the investigation of the selected Pakistani plants for their potential as anticancer agents on human bone and breast cancer cell lines in comparison with non-tumorigenic control cells.

METHODS

The antitumor evaluation was carried out on human bone (MG-63, Saos-2) and breast cancer cell lines (MCF-7, BT-20) in contrast to non-tumorigenic control cells (POB, MCF-12A) via cell viability measurements, cell cycle analysis, Annexin V/PI staining, microscopy based methods as well as migration/invasion determination, metabolic live cell monitoring and western blotting.

RESULTS

After the first initial screening of the plant extracts, two extracts (BORM, VSM) revealed the highest potential with regard to its antitumor activity. Both extracts caused a significant reduction of cell viability in the breast and bone cancer cells in a concentration dependent manner. The effect of VSM is achieved primarily by inducing a G2/M arrest in the cell cycle and the stabilization of the actin stress fibers leading to reduced cell motility. By contrast BORM's cytotoxic properties were caused through the lysosomal-mediated cell death pathway indicated by an upregulation of Bcl-2 expression.

CONCLUSIONS

The antitumor evaluation of certain medicinal plants presented in this study identified the methanolic root extract of Berberis orthobotrys and the methanolic extract of Vincetoxicum arnottianum as promising sources for exhibiting the antitumor activity. Therefore, the indigenous use of the herbal remedies for the treatment of cancer and cancer-related diseases has a scientific basis. Moreover, the present study provides a base for phytochemical investigation of the plant extracts.

Anti-cancer effects of enteric-coated polymers containing mistletoe lectin in murine melanoma cells in vitro and in vivo

In this study, we evaluated the effects of Korean mistletoe (Viscum album L. var. coloratum) coated with a biodegradable polymer (Eudragit(®)) wall on the growth of mouse melanoma in vivo. Oral administration of 4% (430 mg/kg/day) enteric-coated mistletoe resulted in a significant reduction in tumor volume on day 14 compared to the negative control group in B16F10 melanoma-inoculated BDF1 mice. When we measured the survival rate, enteric-coated mistletoe-received mice had a higher survival rate after day 12. Also, we investigated the mechanism involving the cancer cell growth inhibition when melanoma cells were treated with Korean mistletoe lectin (Viscum album L. var. coloratum agglutinin, VCA) and its extract in vitro. As a result, a significant G0/G1 arrest was observed in both B16BL6 and B16F10 melanoma cells with VCA or mistletoe extract. In addition, VCA or mistletoe extract induced an increase in both early and late apoptosis in cells. When we studied the molecular mechanism, our results showed that VCA and mistletoe extract can increase activated multiple caspases (caspase-1, 3, 4, 5, 6, 7, 8, and 9), dose-dependently. We also found out that VCA and mistletoe treatment causes a significant decrease in the expression of procaspase-3 and 8.

Immunopathological and antimicrobial effect of black pepper, ginger and thyme extracts on experimental model of acute hematogenous pyelonephritis in albino rats

Recent studies showed prominent antimicrobial activity of various plant extracts on certain pathogenic microorganisms, therefore we prepared crude aqueous extracts of black pepper, ginger and thyme and carried out an in vitro study by measuring antimicrobial activity of these extracts using the agar well diffusion method. An in vivo study was carried out on 50 adult healthy male albino rats which were divided into 5 groups, 10 rats each. Group 1: negative control group which received saline solution intragastrically daily; Group 2: Positive control group, injected with mixed bacterial suspension of S.aureus and E.coli as a model of pyelonephritis, then received saline solution intragastrically daily; Group 3: injected with the same dose of mixed bacterial suspension, then received 100 mg/kg/day black pepper extract intragastrically; Group 4: injected with mixed bacterial suspension then received 500 mg/kg/day ginger extract intragastrically. Group 5: injected with mixed bacterial suspension then received 500 mg/kg/day thyme extract intragastrically. All groups were sacrificed after either 1 or 4 weeks. Serum and blood samples were collected for lysozyme activity estimation using agarose lysoplate, measurement of nitric oxide production, and lymphocyte transformation test as well as for counting both total and differential leukocytes and erythrocytes. Kidney samples were tested histopathologically. Both in vivo and in vitro results confirm the efficacy of these extracts as natural antimicrobials and suggest the possibility of using them in treatment procedures.