Mitotic arrest and apoptosis in breast cancer cells induced by Origanum majorana extract: upregulation of TNF-α and downregulation of survivin and mutant p53

Enhancing immune and antioxidant responses in Nile tilapia through dietary supplementation with Ulva fasciata extract: A study on gene expression and resistance to Aeromonas hydrophila

BACKGROUND

The study focused on the impact of Ulva fasciata extract (UFE) supplementation in the diets of Nile tilapia (Oreochromis niloticus) on blood and biochemical markers, immune and oxidative responses, and the expression of related genes, with a specific interest in their condition following exposure to Aeromonas hydrophila.

METHODS

Four different levels of UFE were tested in the diets: 0% (0 mg kg- 1) for the control group (U0), and incremental additions of 0.05% (50 mg kg-1), 0.1% (100 mg kg-1), and 0.15% (150 mg kg-1) for the experimental groups U50, U100, and U150 respectively. Groups of 45 fish weighing 3.126 ± 0.120 g were fed these diets over 90 days.

RESULTS

The study found that groups treated with UFE showed statistically significant enhancements (p < 0.05) compared to the control group. These improvements included increased red and white blood cell counts, higher haemoglobin concentrations, greater packed cell volume, and elevated enzyme activities-specifically, superoxide dismutase, catalase, alanine aminotransferase, and aspartate aminotransferase. Additionally, lysozyme and phagocytic activities were notably higher, especially in the U100 group after exposure. Before exposure to Aeromonas hydrophila, all levels of UFE supplementation led to increased expression of TNF-α and COXII genes and decreased NFκ-B expression. After the challenge, UFE intake resulted in varied expression levels of immune and antioxidant genes (TNF-α, NFκ-B, SOD, and COXII) in the liver, with the most effective responses observed in the U50, U100, and U150 groups.

CONCLUSIONS

The findings underscore the potential of dietary UFE as a natural antioxidant and immune booster for Nile tilapia.

Evaluation of the anticancer activity of Origanum Marjoram as a safe natural drink for daily use

BACKGROUND

Chemotherapeutic agents have numerous side effects. There is a major interest in using natural and safe plants as food or drink to prevent from cancer. Origanum marjoram (OMAE) is a medicinal plant that can be used as a tea, food, and additive in traditional medicine.

OBJECTIVE

This study aimed to evaluate the potential anticancer effects of OMAE as a soft drink for daily use against a model cancer, prevention and treatment.

METHOD

MCF-7 cells were chosen as model cancer cells. The MTT assay was used to assess the in vitro inhibitory effects of OMAE on cell growth. Moreover, quantitative real-time PCR (qRT-PCR) was used to detect specific genes associated with cancer, such as ESR1, Bax, Bcl-2, and p53. Furthermore, the DNA damage was evaluated using the comet assay.

RESULTS

OMAE has IC50 of 53.1 and IC90 of 97.5 μg/ml dependent inhibition of cell proliferation after 48 h of treatment toward MCF-7. Also, a significant decrease in the expression level of the ESR1 gene in the MCF-7 cell line. Furthermore, there was a significant increase in the comet length and comet-positive cells after treatment with OMAE (88.7%) compared with those in the untreated control cells (9.5%), suggesting a high induction of DNA damage by OMAE. Also, OMAE showed a modification in bcl-2, tumor suppressor gene (p53), and Bax levels and influenced the BAX/BCL-2 ratio via releasing the cytochrome C.

CONCLUSION

The results of the study were promising, suggesting that the reduced apoptotic rate of MCF-7 breast cancer cells in this work was correlated to the potential anticancer effect of OMAE which would be a suitable preventable drink against cancer. However, further studies are needed to fully understand the potential of OMAE as a cancer treatment.

Anticancer potential of Origanum munzurense extract against MCF-7 breast cancer cell

Origanum munzurense (O. munzurense) is an endemic species of Tunceli region of Turkey. In this study, we investigated in vitro anticancer effect of aqueous extract of O. munzurense (OME) on breast cancer cells (MCF-7). In vitro cytotoxic effect of OME was evaluated in MCF-7 cells by MTT assay. The wound-healing assay was used to examine the inhibition of migration. Annexin V/propidium iodide staining, cell-cycle distribution was assessed by flow cytometry for MCF-7 cells treated with OME. MTT results show that OME demonstrated in vitro cytotoxicity with 600 mg at 48 h on MCF-7. Doses of 400 µg/mL and 600 µg/mL OME significantly suppressed the migration rate of MCF-7 cells. OME significantly decreased the percentage of live cancer cells and showed an apoptotic effect after 48 h of incubation. These results show that OME is effective against breast cancer when administered at high doses and for a long time.

Role of p53 in breast cancer progression: An insight into p53 targeted therapy

The transcription factor p53 is an important regulator of a multitude of cellular processes. In the presence of genotoxic stress, p53 is activated to facilitate DNA repair, cell cycle arrest, and apoptosis. In breast cancer, the tumor suppressive activities of p53 are frequently inactivated by either the overexpression of its negative regulator MDM2, or mutation which is present in 30-35% of all breast cancer cases. Notably, the frequency of p53 mutation is highly subtype dependent in breast cancers, with majority of hormone receptor-positive or luminal subtypes retaining the wild-type p53 status while hormone receptor-negative patients predominantly carry p53 mutations with gain-of-function oncogenic activities that contribute to poorer prognosis. Thus, a two-pronged strategy of targeting wild-type and mutant p53 in different subtypes of breast cancer can have clinical relevance. The development of p53-based therapies has rapidly progressed in recent years, and include unique small molecule chemical inhibitors, stapled peptides, PROTACs, as well as several genetic-based approaches using vectors and engineered antibodies. In this review, we highlight the therapeutic strategies that are in pre-clinical and clinical development to overcome p53 inactivation in both wild-type and mutant p53-bearing breast tumors, and discuss their efficacies and limitations in pre-clinical and clinical settings.

Origanum syriacum L. Attenuates the Malignant Phenotype of MDA-MB231 Breast Cancer Cells

Breast cancer is the leading cause of cancer-related deaths among women. Among breast cancer types, triple negative breast cancer (TNBC) is the most aggressive, and is resistant to hormonal and chemotherapeutic treatments. As such, alternative approaches that may provide some benefit in fighting this debilitating pathology are critically needed; hence the utilization of herbal medicine. Origanum syriacum L., one of the most regularly consumed plants in the Mediterranean region, exhibits antiproliferative effect on several cancer cell lines. However, whether this herb modulates the malignant phenotype of TNBC remains poorly investigated. Here, we show that in MDA-MB-231, a TNBC cell line, Origanum syriacum L. aqueous extract (OSE) inhibited cellular viability, induced autophagy determined by the accumulation of lipidized LC3 II, and triggered apoptosis. We also show that OSE significantly promoted homotypic cell-cell adhesion while it decreased cellular migration, adhesion to fibronectin, and invasion of MDA-MB-231 cells. This was supported by decreased activity of focal adhesion kinase (FAK), reduced α2 integrin expression, and downregulation of secreted PgE₂, MMP2 and MMP-9, in OSE-treated cells. Finally, we also show that OSE significantly inhibited angiogenesis and downregulated the level of nitric oxide (NO) production. Our findings demonstrate the ability of OSE to attenuate the malignant phenotype of the MDA-MB-231 cells, thus presenting Origanum syriacum L. as a promising potential source for therapeutic compounds for TNBC.

Origanum majorana L. Extract Attenuated Benign Prostatic Hyperplasia in Rat Model: Effect on Oxidative Stress, Apoptosis, and Proliferation

Benign prostatic hyperplasia (BPH) is a widespread androgenic illness influencing elderly men. It is distinguished by prostatic epithelial and stromal muscle cell proliferation. Inflammation, oxidative stress, and apoptosis have all been interrelated to the development of BPH. Marjoram (Origanum majorana L.) is a herb with reported antiproliferative, proapoptotic, and antioxidative properties, which have not yet been studied in relation to BPH. Consequently, in this work, an ethanolic extract of O. majorana was prepared in two doses (250 and 500 mg/kg/day) to be injected into castrated rats after induction of a testosterone-BPH model. Testosterone propionate (TP) was subcutaneously injected (0.5 mg/kg/day) for one week after castration to induce BPH. Forty adult Wistar male rats were randomly allocated into five groups: control, BPH model, high and low O. majorana doses (250, 500 mg/kg/day), and finasteride (FN) (0.8 mg/kg/day) as a positive control. Treatment was continued with drugs/normal saline for 28 days. Rat’s body and prostate were weighed, prostate index (PI) and % of prostate growth inhibition were calculated, serum dihydrotestosterone (DHT), prostatic content of superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (TAC), and malondialdehyde (MDA), DN damage, histopathological changes, immune expression of proliferating cell nuclear antigen (PCNA), caspase-3, α-SMA, and TGF-β1 were assessed. In addition, molecular quantitative PCR and ELISA analyses were performed to identify the expression of mRNAs and related proteins of both caspase-3 and TGF-β1 in prostate tissue from O. majorana-treated and untreated groups. Rats with BPH had significantly higher prostate weights and PI, higher DHT, DNA damage (8-hydroxyguanine, 8-OH-dG), and MDA levels with prominent PCNA, α-SMA, and TGF-β expression, but lower SOD, CAT, and TAC activity and caspase-3 expression. O. majorana (250 and 500 mg/kg/day)-treated groups revealed a decrease in prostate weights and PI, lower levels of DHT, suppressed oxidative stress, reduced tissue proliferation and fibrosis, and restored antioxidant and proapoptotic activity. Additionally, quantitative PCR and ELISA analysis showed that treatment with O. majorana significantly upregulated the expression of caspase-3 and downregulated the expression of TGF-β in prostate tissues of BPH rats. The data were confirmed by the immunohistological reactivity of these targeted markers in the prostate tissues. These effects were more significant with O. majorana 500 mg/mL/rat. In conclusion, the current study indicates the efficient use of O. majorana in the treatment of testosterone-induced BPH through its antiproliferative, proapoptotic, and antioxidative mechanisms.

Traditional use, phytochemistry, toxicology, and pharmacology of Origanum majorana L

ETHNOPHARMACOLOGICAL RELEVANCE

Origanum majorana L., is an aromatic and medicinal plant distributed in different parts of Mediterranean countries. This species is widely used in traditional medicine for the treatment of many diseases such as allergies, hypertension, respiratory infections, diabetes, stomach pain, and intestinal antispasmodic.

AIM OF THE REVIEW

This work reports previous studies on O. majorana concerning its taxonomy, botanical description, geographical distribution, traditional use, bioactive compounds, toxicology, and biological effects.

MATERIALS AND METHODS

Different scientific data bases such as Web of Science, Scopus, Wiley Online, SciFinder, Google Scholar, PubMed, ScienceDirect, and SpringerLink were consulted to collect data about O. majorana. The presented data emphasis bioactive compounds, traditional uses, toxicological investigations, and biological activities of O. majorana.

RESULTS

The findings of this work marked an important correlation between the traditional use of O. majorana as an anti-allergic, antihypertensive, anti-diabetic agent, and its biological effects. Indeed, pharmacological investigations showed that essential oils and extracts from O. majorana exhibit different biological properties, particularly; antibacterial, antifungal, antioxidant, antiparasitic, antidiabetic, anticancer, nephrotoxicity protective, anti-inflammatory, analgesic and anti-pyretic, hepatoprotective, and antimutagenic effects. Toxicological evaluation confirmed the safety and innocuity of this species and supported its medicinal uses. Several bioactive compounds belonging to different chemical family such as terpenoids, flavonoids, and phenolic acids were also identified in O. majorana.

CONCLUSIONS

The results suggest that the pharmacological properties of O. majorana confirm its traditional uses. Indeed, O. majorana essential oils showed remarkable antimicrobial, antioxidant, anticancer, anti-inflammatory, antimutagenic, nephroprotective, and hepatoprotective activities. However, further investigations regarding the evaluation of molecular mechanisms of identified compounds against human cancer cell lines, inflammatory process, and microbial infections are needed to validate pharmacodynamic targets. The toxicological investigation of O. Majorana confirmed its safety and therefore encouraged pharmacokinetic evaluation tests to validate its bioavailability.

CYP2E1 inhibition and NF_κB Signaling Pathway are Involved in the Protective Molecular Effect of Origanum floribundum against Acetaminophen-induced acute Hepatotoxicity in Rats

The present study aimed to estimate the potential and the molecular mechanism of the hydro-ethanolic extract of O.floribundum against acetaminophen (AC) induced hepatotoxicity. Four groups of female Wistar rats (n=6) was formed to study the hepatoprotective effect of O.floribundum extract against acetaminophen overdose (2 g/kg): Groups N and AC received orally tap water for 03 days and Groups O. floribundum + AC and N+O.floribundum: received orally O. floribundum extract (400 mg/kg). After 1hour (h) of the last dose administered, the paracetamol solution (2 g/kg) is administered orally for group AC and O. floribundum + AC. The hydroethanolic extract of O. floribundum shows strong antioxidant activity "in-vitro". After 24 h, a single dose of acetaminophen increased significantly serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and the activity of alkaline phosphatase (ALP) significantly and decreased total protein and albumin levels compared to the normal group. These alterations are confirmed by histological observations with inflammation markers (congestion, inflammatory cells infiltration). These observed effects are mainly due to the over-expression of the CYP2E1 and NF_ κ B genes marked in this study by quantitative RT-PCR. Also, acetaminophen overdose leads to activation of the mitochondrial permeability transition (MPT). leading to hepatocyte necrosis. Pretreatment with O.floribundum before acetaminophen administration removes all previously observed biochemical, histological. and mitochondrial manifestations. These results suggest that O.floribundum has a potent antioxidant power and an interesting hepatoprotective activity against acetaminophen toxicity partly due to the inhibition of CYP2E1 and NF_ κ B genes expression.

Oregano Phytocomplex Induces Programmed Cell Death in Melanoma Lines via Mitochondria and DNA Damage

Plant secondary metabolites possess chemopreventive and antineoplastic properties, but the lack of information about their exact mechanism of action in mammalian cells hinders the translation of these compounds in suitable therapies. In light of this, firstly, Origanum vulgare L. hydroalcoholic extract was chemically characterized by spectrophotometric and chromatographic analyses; then, the molecular bases underlying its antitumor activity on B16-F10 and A375 melanoma cells were investigated. Oregano extract induced oxidative stress and inhibited melanogenesis and tumor cell proliferation, triggering programmed cell death pathways (both apoptosis and necroptosis) through mitochondria and DNA damage. By contrast, oregano extract was safe on healthy tissues, revealing no cytotoxicity and mutagenicity on C2C12 myoblasts, considered as non-tumor proliferating cell model system, and on Salmonella strains, by the Ames test. All these data provide scientific evidence about the potential application of this food plant as an anticancer agent in in vivo studies and clinical trials.

Antipsychotics drug aripiprazole as a lead against breast cancer cell line (MCF-7) in vitro

Breast cancer is the second leading cause of death among women globally. The existing treatment options for breast cancer are largely associated with severe toxicities, and lower efficacies. Therefore, there is an urgent need for the development of non-toxic effective drugs against breast cancer. For this purpose, drug repositioning strategy was used to evaluate the anti-cancer potential of a library of heterocyclic drugs. The major advantage of drug repurposing is that the pharmacokinetic, pharmacodynamic, and toxicity profiles of drugs are well documented. In the current study, we screened 97 drugs of different chemical classes, and among them aripiprazole, an antipsychotic drug, was found to be sufficiently active against breast cancer cell line MCF-7. Aripiprazole showed a cytotoxicity (IC50 = 12.1 ± 0.40 μM) to MCF-7 cells, comparable to the standard anticancer drug doxorubicin (IC50 = 1.25 ± 0.34 μM). Aripiprazole was also found to be active against other cancer cell lines, including MDA-MB-231 (IC50 = 19.83 ± 0.27 μM), AU565 (IC50 = 18.02 ± 0.44 μM), and BT-474 (IC50 = 36.42 ± 0.12 μM). Aripiprazole significantly inhibited the cell cycle progression at subG0G1 phase, and enhanced apoptosis in MCF-7 breast cancer cells. The drug was also able to significantly increase the nuclear condensation, and modulated the expression of certain genes involved in breast cancer, such as caspases 3, and 9, BAK-1, C-MYC, BCL2L1, BCL-10, and BCL-2. Further studies are needed to explore the effect of aripiprazole on intrinsic and extrinsic pathways of apoptosis in cancer cells.

Origanum majorana Essential Oil Triggers p38 MAPK-Mediated Protective Autophagy, Apoptosis, and Caspase-Dependent Cleavage of P70S6K in Colorectal Cancer Cells

Colorectal cancer (CRC) is the third most common type of cancer in terms of incidence and mortality worldwide. Here we have investigated the anti-colon cancer potential of Origanum majorana essential oil (OMEO) and its underlying mechanisms of action. We showed that OMEO significantly inhibited the cellular viability and colony growth of human HT-29 colorectal cancer cells. OMEO induced protective autophagy, associated with downregulation of the mTOR/p70S6K pathway, and activated caspase-8 and caspase-9-dependent apoptosis. Blockade of autophagy with 3-methyladenine (3-MA) and chloroquine (CQ), two autophagy inhibitors, potentiated the OMEO-induced apoptotic cell death. Inversely, inhibition of apoptosis with the pan-caspase inhibitor, Z-VAD-FMK, significantly reduced cell death, suggesting that apoptosis represents the main mechanism of OMEO-induced cell death. Mechanistically, we found that OMEO induces protective autophagy and apoptotic cells death via the activation of the p38 MAPK signaling pathway. Pharmacological inhibition of p38 MAPK by the p38 inhibitors SB 202190 and SB 203580 not only significantly decreased apoptotic cell death, but also reduced the autophagy level in OMEO treated HT-29 cells. Strikingly, we found that OMEO also induces p38 MAPK-mediated caspase-dependent cleavage of p70S6K, a protein reported to be overexpressed in colon cancer and associated with drug resistance. Our findings suggest that OMEO inhibits colon cancer through p38 MAPK-mediated protective autophagy and apoptosis associated with caspase-dependent cleavage of p70S6K. To the best of our knowledge, this study is the first to report on the implications of the p38 MAPK signaling pathway in targeting p70S6K to caspase cleavage.

Origanum majorana Ethanolic Extract Promotes Colorectal Cancer Cell Death by Triggering Abortive Autophagy and Activation of the Extrinsic Apoptotic Pathway

Colorectal cancer is considered as the third leading cause of cancer death. In the present study, we investigated the potential anticancer effect and the molecular mechanism of Origanum majorana ethanolic extract (OME) against human colorectal cancer cells. We showed that OME exhibited strong anti-proliferative activity in a concentration- and time-dependent manner against two human colorectal cancer cell lines (HT-29 and Caco-2). OME inhibited cell viability, colony growth and induced mitotic arrest of HT-29 cells. Also, OME induced DNA damage, triggered abortive autophagy and activated a caspase 3 and 7-dependent extrinsic apoptotic pathway, most likely through activation of the TNFα pathway. Time-course analysis revealed that DNA damage occurred concomitantly with abortive autophagy after 4 h post-OME treatment while apoptosis was activated only 24 h later. Blockade of autophagy initiation, by 3-methyladenine, partially rescued OME-induced cell death. Cell viability arose from 37% in control group to 67% in group pre-treated with 3-MA before addition of OME. Inhibition of apoptosis, however, had a minimal effect on cell viability; it rose from 37% in control group to 43% in group pre-treated with Z-VAD-FMK. We also found that OME downregulated survivin in HT-29 cells. Our findings provide a strong evidence that O. majorana extract possesses strong anti-colon cancer potential, at least, through induction of autophagy and apoptosis. These finding provide the basis for therapeutic potential of O. majorana in the treatment of colon cancer.

Marjoram Relaxes Rat Thoracic Aorta Via a PI3-K/eNOS/cGMP Pathway

Despite pharmacotherapeutic advances, cardiovascular disease (CVD) remains the primary cause of global mortality. Alternative approaches, such as herbal medicine, continue to be sought to reduce this burden. Origanum majorana is recognized for many medicinal values, yet its vasculoprotective effects remain poorly investigated. Here, we subjected rat thoracic aortae to increasing doses of an ethanolic extract of Origanum majorana (OME). OME induced relaxation in a dose-dependent manner in endothelium-intact rings. This relaxation was significantly blunted in denuded rings. N(ω)-nitro-l-arginine methyl ester (L-NAME) or 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ) significantly reduced the OME-induced vasorelaxation. Cyclic guanosine monophosphate (cGMP) levels were also increased by OME. Moreover, wortmannin or LY294002 significantly reduced OME-induced vasorelaxation. Blockers of ATP-sensitive or Ca²⁺-activated potassium channels such as glibenclamide or tetraethylamonium (TEA), respectively, did not significantly affect OME-induced relaxation. Similarly, verapamil, a Ca²⁺ channel blocker, indomethacin, a non-selective cyclooxygenase inhibitor, and pyrilamine, a H1 histamine receptor blocker, did not significantly modulate the observed relaxation. Taken together, our results show that OME induces vasorelaxation via an endothelium-dependent mechanism involving the phosphoinositide 3-kinase (PI3-K)/ endothelial nitric oxide (NO) synthase (eNOS)/cGMP pathway. Our findings further support the medicinal value of marjoram and provide a basis for its beneficial intake. Although consuming marjoram may have an antihypertensive effect, further studies are needed to better determine its effects in different vascular beds.

Natural Product Interventions for Chemotherapy and Radiotherapy-Induced Side Effects

Cancer is the second leading cause of death in the world. Chemotherapy and radiotherapy are the common cancer treatments. However, the development of adverse effects resulting from chemotherapy and radiotherapy hinders the clinical use, and negatively reduces the quality of life in cancer patients. Natural products including crude extracts, bioactive components-enriched fractions and pure compounds prepared from herbs as well as herbal formulas have been proved to prevent and treat cancer. Of significant interest, some natural products can reduce chemotherapy and radiotherapy-induced oral mucositis, gastrointestinal toxicity, hepatotoxicity, nephrotoxicity, hematopoietic system injury, cardiotoxicity, and neurotoxicity. This review focuses in detail on the effectiveness of these natural products, and describes the possible mechanisms of the actions in reducing chemotherapy and radiotherapy-induced side effects. Recent advances in the efficacy of natural dietary supplements to counteract these side effects are highlighted. In addition, we draw particular attention to gut microbiotan in the context of prebiotic potential of natural products for the protection against cancer therapy-induced toxicities. We conclude that some natural products are potential therapeutic perspective for the prevention and treatment of chemotherapy and radiotherapy-induced side effects. Further studies are required to validate the efficacy of natural products in cancer patients, and elucidate potential underlying mechanisms.

Cytotoxicity of the Aqueous Extract and Organic Fractions from Origanum majorana on Human Breast Cell Line MDA-MB-231 and Human Colon Cell Line HT-29

The toxicity of the aqueous extract of Origanum majorana was tested (5 and 10 g/kg) in albino mice. No symptoms of toxicity or mortality were observed. The mice survived being active and healthy during all 14 days of observation. In addition, the weight measurement of the left and right kidneys, heart, and liver shows no significant difference between the control, 5 g/kg, and 10 g/kg. All extracts (aqueous, petroleum ether, dichloromethane, ethyl acetate, methanolic, and depleted aqueous extracts) of Origanum majorana tested against both types of cancer cells showed a more pronounced cytotoxic effect against breast cell line MDA-MB-231 than colon cells line HT-29 cells. The most marked effect is that of the ethyl acetate extract with IC₅₀ 30.90 ± 1.39 and 50.11 ± 1.44 (µg/ml), respectively. HPLC analysis of extracts from Origanum majorana showed that this plant contained polyphenols and flavonoids, which may be responsible for the biological activities found.

Natural products targeting the p53-MDM2 pathway and mutant p53: Recent advances and implications in cancer medicine

The p53 tumor suppressor plays a major role in controlling the initiation and development of cancer by regulating cell cycle arrest, apoptosis, senescence, and DNA repair. The MDM2 oncogene is a major negative regulator of p53 that inhibits the activity of p53 and reduces its protein stability. MDM2, p53, and the p53-MDM2 pathway represent well-documented targets for preventing and/or treating cancer. Natural products, especially those from medicinal and food plants, are a rich source for the discovery and development of novel therapeutic and preventive agents against human cancers. Many natural product-derived MDM2 inhibitors have shown potent efficacy against various human cancers. In contrast to synthetic small-molecule MDM2 inhibitors, the majority of which have been designed to inhibit MDM2-p53 binding and activate p53, many natural product inhibitors directly decrease MDM2 expression and/or MDM2 stability, exerting their anticancer activity in both p53-dependent and p53-independent manners. More recently, several natural products have been reported to target mutant p53 in cancer. Therefore, identification of natural products targeting MDM2, mutant p53, and the p53-MDM2 pathway can provide a promising strategy for the development of novel cancer chemopreventive and chemotherapeutic agents. In this review, we focus our discussion on the recent advances in the discovery and development of anticancer natural products that target the p53-MDM2 pathway, emphasizing several emerging issues, such as the efficacy, mechanism of action, and specificity of these natural products.

Estrogen receptor-α promoter methylation is a biomarker for outcome prediction of cisplatin resistance in triple-negative breast cancer

A number of previous studies have indicated the presence of a link between estrogen receptor-α (ERα) methylation and triple-negative breast cancer (TNBC). However, the association between ERα methylation and drug resistance during the treatment of TNBC remains unclear. Methylation-specific polymerase chain reaction was used to investigate the methylation of ERα in the genomic DNA of 35 patients with TNBC who were defined as cisplatin-based chemotherapy-resistant using chemosensitivity testing. Survival probabilities by covariates were assessed using Kaplan-Meier estimator survival analysis and Cox's proportional hazards models, adjusting for age, menopausal status, tumor size, lymph node metastasis and ERα promoter DNA methylation. Of the 35 patients with TNBC analyzed, 8 exhibited ERα promoter DNA methylation. Cisplatin resistance was confirmed to be overwhelmingly associated with ERα methylation by univariate and multivariate analysis. Even in a limited analysis in patients with ERα methylation, the results generated from methylated tumor tissue and unmethylated tumor tissue revealed that expression of breast cancer type 1/2 susceptibility proteins was increased in ERα-methylated breast tumor tissue compared with in unmethylated tissue. The ERα methylation group tended to have significantly shorter progression-free (P=0.010) and overall (P=0.023) survival times compared with those in the unmethylated group. Similarly, shorter progression-free (P=0.024) and overall (P=0.018) survival times were observed in the cisplatin-resistant group compared with the cisplatin-non-resistant group. ERα methylation predicts a poor clinical outcome for patients with TNBC. The results of the present study indicated that ERα methylation may be a candidate surrogate biomarker for outcome prediction and cisplatin resistance in TNBC. Further investigation is required to identify potential biomarkers in a larger cohort in a prospective study.

Anticarcinogenic Effect of Spices Due to Phenolic and Flavonoid Compounds-In Vitro Evaluation on Prostate Cells

This study shows the effects of spices, and their phenolic and flavonoid compounds, on prostate cell lines (PNT1A, 22RV1 and PC3). The results of an MTT assay on extracts from eight spices revealed the strongest inhibitory effects were from black pepper and caraway seed extracts. The strongest inhibitory effect on prostatic cells was observed after the application of extracts of spices in concentration of 12.5 mg·mL^-1. An LC/MS analysis identified that the most abundant phenolic and flavonoid compounds in black pepper are 3,4-dihydroxybenzaldehyde and naringenin chalcone, while the most abundant phenolic and flavonoid compounds in caraway seeds are neochlorogenic acid and apigenin. Using an MTT assay for the phenolic and flavonoid compounds from spices, we identified the IC₅₀ value of ~1 mmol·L^-1 PNT1A. The scratch test demonstrated that the most potent inhibitory effect on PNT1A, 22RV1 and PC3 cells is from the naringenin chalcone contained in black pepper. From the spectrum of compounds assessed, the naringenin chalcone contained in black pepper was identified as the most potent inhibitor of the growth of prostate cells.

Salvia fruticosa Induces Vasorelaxation In Rat Isolated Thoracic Aorta: Role of the PI3K/Akt/eNOS/NO/cGMP Signaling Pathway

Salvia fruticosa (SF) Mill. is traditionally used for its antihypertensive actions. However, little is known about its pharmacologic and molecular mechanisms of action. Here we determined the effects of an ethanolic extract of SF leaves on rings of isolated thoracic aorta from Sprague-Dawley rats. Our results show that SF extract increased nitric oxide production and relaxed endothelium-intact rings in a dose-dependent (0.3 µg/ml–1 mg/ml) manner, and the maximum arterial relaxation (R_max) was significantly reduced with endothelium denudation. Pretreatment of endothelium-intact rings with L-NAME (a non-selective inhibitor of nitric oxide synthase, 100 µM), or ODQ (an inhibitor of soluble guanylyl cyclase, 10 µM) significantly diminished SF-mediated vasorelaxation. Furthermore, SF induced Akt phosphorylation as well as increased cGMP levels in rings treated with increasing doses of SF. Prior exposure to PI3K inhibitors, wortmannin (0.1 µM) or LY294002 (10 µM), decreased cGMP accumulation and attenuated the SF-induced vasorelaxation by approximately 50% (R_max). SF-evoked relaxation was not affected by indomethacin, verapamil, glibenclamide, tetraethylammonium, pyrilamine or atropine. Taken together, our results indicate that SF induces endothelium-dependent vasorelaxation through the PI3K/Akt/eNOS/NO/sGC/cGMP signaling pathway. Our data illustrate the health-orientated benefits of consuming SF which may act as an antihypertensive agent to reduce the burden of cardiovascular complications.

Mechanistic insight into carnosol-mediated pharmacological effects: Recent trends and advancements

For several decades, bioactive phytochemicals have been appreciated to prevent and cure various lethal diseases. Many studies have proven the ability of dietary phytochemicals to avoid and retard tumor initiation and progression. Among the pharmacologically active moieties, terpenoids are considered one of the most important classes. Carnosol, is also a kind of diterpenoid, which known to possess a range of therapeutic effects such as anti-cancer, anti-inflammatory, and anti-oxidant activities. All these effects are mediated via modulating different signaling cascades, including apoptosis regulating molecules (Bax/Bcl2), prosurvival-proproliferative molecules (Akt/mTOR, MAPK), transcription factors like NF-kappaB, STAT3-6, and steroid receptors, such as androgen and estrogen receptors. The present review highlights the recent trends and advancements have been done in the field of research by using carnosol.

Inhibitory Effect of Ginseng on Breast Cancer Cell Line Growth Via Up-Regulation of Cyclin Dependent Kinase Inhibitor, p21 and p53

Objective:

Breast cancer is global female health problem worldwide. Most of the currently used agents for breast cancer treatment have toxic side-effects. Ginseng root, an oriental medicine, has many health benefits and may exhibit direct anti-cancer properties. This study was performed to assess the effects of ginseng on breast cancer cell lines.

Materials and Methods:

Cytotoxicity of ginseng extract was measured by MTT assay after exposure of MDA-MB-231, MCF-10A and MCF-7 breast cancer cells to concentrations of 0.25, 0.5, 1, 1.5, 2 and 2.5 mg/well. Expression levels of p21WAF, p16INK4A, Bcl-2, Bax and P53 genes were analyzed by quantitative real time PCR.

Results:

The treatment resulted in inhibition of cell proliferation in a dose-and time-dependent manner. p53, p21WAF1and p16INK4A expression levels were up-regulated in ginseng treated MDA-MB-231 and MCF-7 cancer cells compared to untreated controls and in MCF-10A cells. The expression levels of Bcl2 in the MDA-MB-231 and MCF-7 cells were down-regulated. In contrast, that of Bax was significantly up-regulated.

Conclusion:

The results of this study revealed that ginseng may inhibit breast cancer cell growth by activation of the apoptotic pathway.

Fighting Cancer with Corroles

Corroles are exceptionally promising platforms for the development of agents for simultaneous cancer-targeting imaging and therapy. Depending on the element chelated by the corrole, these theranostic agents may be tuned primarily for diagnostic or therapeutic function. Versatile synthetic methodologies allow for the preparation of amphipolar derivatives, which form stable noncovalent conjugates with targeting biomolecules. These conjugates can be engineered for imaging and targeting as well as therapeutic function within one theranostic assembly. In this review, we begin with a brief outline of corrole chemistry that has been uniquely useful in designing corrole-based anticancer agents. Then we turn attention to the early literature regarding corrole anticancer activity, which commenced one year after the first scalable synthesis was reported (1999-2000). In 2001, a major advance was made with the introduction of negatively charged corroles, as these molecules, being amphipolar, form stable conjugates with many proteins. More recently, both cellular uptake and intracellular trafficking of metallocorroles have been documented in experimental investigations employing advanced optical spectroscopic as well as magnetic resonance imaging techniques. Key results from work on both cellular and animal models are reviewed, with emphasis on those that have shed new light on the mechanisms associated with anticancer activity. In closing, we predict a very bright future for corrole anticancer research, as it is experiencing exponential growth, taking full advantage of recently developed imaging and therapeutic modalities.

Combination of salinomycin and silver nanoparticles enhances apoptosis and autophagy in human ovarian cancer cells: an effective anticancer therapy

Ovarian cancer is one of the most important malignancies, and the origin, detection, and pathogenesis of epithelial ovarian cancer remain elusive. Although many cancer drugs have been developed to dramatically reduce the size of tumors, most cancers eventually relapse, posing a critical problem to overcome. Hence, it is necessary to identify possible alternative therapeutic approaches to reduce the mortality rate of this devastating disease. To identify alternative approaches, we first synthesized silver nanoparticles (AgNPs) using a novel bacterium called Bacillus clausii. The synthesized AgNPs were homogenous and spherical in shape, with an average size of 16–20 nm, which are known to cause cytotoxicity in various types of human cancer cells, whereas salinomycin (Sal) is able to kill cancer stem cells. Therefore, we selected both Sal and AgNPs to study their combined effect on apoptosis and autophagy in ovarian cancer cells. The cells treated with either Sal or AgNPs showed a dose-dependent effect with inhibitory concentration (IC)-50 values of 6.0 µM and 8 µg/mL for Sal and AgNPs, respectively. To determine the combination effect, we measured the IC₂₅ values of both Sal and AgNPs (3.0 µM and 4 µg/mL), which showed a more dramatic inhibitory effect on cell viability and cell morphology than either Sal or AgNPs alone. The combination of Sal and AgNPs had more pronounced effect on cytotoxicity and expression of apoptotic genes and also significantly induced the accumulation of autophagolysosomes, which was associated with mitochondrial dysfunction and loss of cell viability. Our data show a strong synergistic interaction between Sal and AgNPs in tested cancer cells. The combination treatment increased the therapeutic potential and demonstrated the relevant targeted therapy for the treatment of ovarian cancer. Furthermore, we provide, for the first time, a mode of action for Sal and AgNPs in ovarian cancer cells: enhanced apoptosis and autophagy.

Dillenia suffruticosa dichloromethane root extract induced apoptosis towards MDA-MB-231 triple-negative breast cancer cells

ETHNOPHARMACOLOGICAL RELEVANCE

Dillenia suffruticosa is traditionally used for treatment of cancerous growth including breast cancer in Malaysia.

AIM OF THE STUDY

Dillenia suffruticosa is a well-known medicinal plant in Malaysia for the treatment of cancer. Nevertheless, no study has been reported the cytotoxicity of this plant towards MDA-MB-231 triple-negative breast cancer cells. The present study was designed to investigate the mode of cell death and signalling pathways of MDA-MB-231 cells treated with dichloromethane Dillenia suffruticosa root extract (DCM-DS).

METHODS

Extraction of Dillenia suffruticosa root was performed by the use of sequential solvent procedure. The cytotoxicity of DCM-DS was determined by using MTT assay. The mode of cell death was evaluated by using an inverted light microscope and flow cytometry analysis using Annexin-V/PI. Cell cycle analysis and measurement of reactive oxygen species level were performed by using flow cytometry. The cells were treated with DCM-DS and antioxidants α-tocopherol or ascorbic acid to evaluate the involvement of ROS in the cytotoxicity of DCM-DS. Effect of DCM-DS on the expression of antioxidant, apoptotic, growth, survival genes and proteins were analysed by using GeXP-based multiplex system and Western blot, respectively. The cytotoxicity of compounds isolated from DCM-DS was evaluated towards MDA-MB-231 cells using MTT assay.

RESULTS

DCM-DS induced apoptosis, G2/M phase cell cycle arrest and oxidative stress in MDA-MB-231 cells. The induction of apoptosis in MDA-MB-231 cells by DCM-DS is possibly due to the activation of pro-apoptotic JNK1 and down-regulation of anti-apoptotic ERK1, which in turn down-regulates anti-apoptotic BCL-2 to increase the BAX/BCL-2 ratio to initiate the mitochondrial apoptotic pathway. The cell cycle arrest in DCM-DS-treated MDA-MB-231 cells is possibly via p53-independent but p21-dependent pathway. A total of 3 triterpene compounds were isolated from DCM-DS. Betulinic acid appears to be the most major and most cytotoxic compound in DCM-DS.

CONCLUSION

The data suggest the potential application of DCM-DS in the treatment of triple-negative breast cancer.

Oregano demonstrates distinct tumour-suppressive effects in the breast carcinoma model

PURPOSE

There has been a considerable interest in the identification of natural plant foods for developing effective agents against cancer. Thus, the anti-tumour effects of oregano in the in vivo and in vitro breast cancer model were evaluated.

METHODS

Lyophilized oregano (ORE) was administered at two concentrations of 0.3 and 3 % through diet. The experiment was terminated 14 weeks after carcinogen administration. At autopsy, mammary tumours were removed and prepared for histopathological and immunohistochemical analysis. Moreover, in vitro evaluation in MCF-7 cells was carried out.

RESULTS

Low-dose ORE suppressed tumour frequency by 55.5 %, tumour incidence by 44 %, and tumour volume by 44.5 % compared to control animals. Analysis of rat tumour cells showed Ki67, VEGFR-2, CD24, and EpCAM expression decrease and caspase-3 expression increase after low-dose ORE treatment. High-dose ORE lengthened tumour latency by 12.5 days; moreover, Bcl-2, VEGFR-2, CD24, and EpCAM expression decrease and caspase-3 expression increase in carcinoma cells were observed. Histopathological analysis revealed a decrease in the ratio of high-/low-grade carcinomas in both treated groups. In vitro studies showed that ORE decreased survival and proliferation of MCF-7 cells. In ORE-treated MCF-7 cells, an increase in cells expressing sub-G ₀/G ₁ DNA content and an increase in the percentage of annexin V/PI positive MCF-7 cells were observed. In vitro, both caspase-dependent and possible non-caspase-dependent apoptotic pathways were found. The deactivation of anti-apoptotic activity of Bcl-2, a decrease in mitochondrial membrane potential, and the activation of mitochondrial apoptosis pathway were observed in the ORE-treated MCF-7 cells.

CONCLUSIONS

Our results demonstrate, for the first time, a distinct tumour-suppressive effect of oregano in the breast cancer model.

Molecular mechanism of anti-cancer activity of phycocyanin in triple-negative breast cancer cells

Background

Triple-negative breast cancers represent an important clinical challenge, as these cancers do not respond to conventional endocrine therapies or other available targeted agents. Phycocyanin (PC), a natural, water soluble and non-toxic molecule is shown to have potent anti-cancer property.

Methods

In this study, we determined the efficacy of PC as an anti-neoplastic agent in vitro on a series of breast cancer cell lines. We studied effects of PC in inducing DNA damage and apoptosis through western blot and qPCR. Also, anti-metastatic and anti-angiogenic properties were studied by classic wound healing and vasculogenic mimicry assays.

Results

We found that triple negative MDA-MB-231 cells were most sensitive to PC (IC50 : 5.98 ± 0.95 μM) as compared to other cells. They also showed decreased cell proliferation and reduced colony formation ability upon treatment with PC. Profile of Cell cycle analysis showed that PC caused G1 arrest which could be attributed to decreased mRNA levels of Cyclin E and CDK-2 and increased p21 levels. Mechanistic studies revealed that PC induced apoptosis as evident by increase in percentage of annexin positive cells, increase in γ-H2AX levels, and by changing the Bcl-2/Bax ratio followed by release of cytochrome C and increased Caspase 9 levels. MDA MB 231 cells treated with PC resulted in decreased cell migration and increased cell adhesive property and also showed anti-angiogenic effects. We also observed that PC suppressed cyclooxygenase-2 (COX-2) expression and prostaglandin E(2) production. All these biological effects of phycocyanin on MDA MB 231 cells could be attributed to decreased MAPK signaling pathway. We also observed that PC is non-toxic to non-malignant cells, platelets and RBC’s.

Conclusion

Taken together, these findings demonstrate, for the first time, that PC may be a promising anti-neoplastic agent for treatment of triple negative breast cancers.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1784-x) contains supplementary material, which is available to authorized users.

Rhus coriaria induces senescence and autophagic cell death in breast cancer cells through a mechanism involving p38 and ERK1/2 activation

Here, we investigated the anticancer effect of Rhus coriaria on three breast cancer cell lines. We demonstrated that Rhus coriaria ethanolic extract (RCE) inhibits the proliferation of these cell lines in a time- and concentration-dependent manner. RCE induced senescence and cell cycle arrest at G1 phase. These changes were concomitant with upregulation of p21, downregulation of cyclin D1, p27, PCNA, c-myc, phospho-RB and expression of senescence-associated β-galactosidase activity. No proliferative recovery was detected after RCE removal. Annexin V staining and PARP cleavage analysis revealed a minimal induction of apoptosis in MDA-MB-231 cells. Electron microscopy revealed the presence of autophagic vacuoles in RCE-treated cells. Interestingly, blocking autophagy by 3-methyladenine (3-MA) or chloroquine (CQ) reduced RCE-induced cell death and senescence. RCE was also found to activate p38 and ERK1/2 signaling pathways which coincided with induction of autophagy. Furthermore, we found that while both autophagy inhibitors abolished p38 phosphorylation, only CQ led to significant decrease in pERK1/2. Finally, RCE induced DNA damage and reduced mutant p53, two events that preceded autophagy. Our findings provide strong evidence that R. coriaria possesses strong anti-breast cancer activity through induction of senescence and autophagic cell death, making it a promising alternative or adjunct therapeutic candidate against breast cancer.

Carnosol induces ROS-mediated beclin1-independent autophagy and apoptosis in triple negative breast cancer

Background

In this study we investigated the in vitro and in vivo anticancer effect of carnosol, a naturally occurring polyphenol, in triple negative breast cancer.

Results

We found that carnosol significantly inhibited the viability and colony growth induced G2 arrest in the triple negative MDA-MB-231. Blockade of the cell cycle was associated with increased p21/WAF1 expression and downregulation of p27. Interestingly, carnosol was found to induce beclin1-independent autophagy and apoptosis in MDA-MB-231 cells. The coexistence of both events, autophagy and apoptosis, was confirmed by electron micrography. Induction of autophagy was found to be an early event, detected within 3 h post-treatment, which subsequently led to apoptosis. Carnosol treatment also caused a dose-dependent increase in the levels of phosphorylated extracellular signal-regulated kinase 1 and 2 (pERK1/2). Moreover, we show that carnosol induced DNA damage, reduced the mitochondrial potential and triggered the activation of the intrinsic and extrinsic apoptotic pathway. Furthermore, we found that carnosol induced a dose-dependent generation of reactive oxygen species (ROS) and inhibition of ROS by tiron, a ROS scavenger, blocked the induction of autophagy and apoptosis and attenuated DNA damage. To our knowledge, this is the first report to identify the induction of autophagy by carnosol.

Conclusion

In conclusion our findings provide strong evidence that carnosol may be an alternative therapeutic candidate against the aggressive form of breast cancer and hence deserves more exploration.

Early diagnostic value of survivin and its alternative splice variants in breast cancer

BACKGROUND

The inhibitor of apoptosis (IAP) protein Survivin and its splice variants are differentially expressed in breast cancer tissues. Our previous work showed Survivin is released from tumor cells via small membrane-bound vesicles called exosomes. We, therefore, hypothesize that analysis of serum exosomal Survivin and its splice variants may provide a novel biomarker for early diagnosis of breast cancer.

METHODS

We collected sera from forty breast cancer patients and ten control patients who were disease free for 5 years after treatment. In addition, twenty-three paired breast cancer tumor tissues from those same 40 patients were analyzed for splice variants. Serum levels of Survivin were analyzed using ELISA and exosomes were isolated from this serum using the commercially available ExoQuick kit, with subsequent Western blots and immunohistochemistry performed.

RESULTS

Survivin levels were significantly higher in all the breast cancer samples compared to controls (p < 0.05) with exosome amounts significantly higher in cancer patient sera compared to controls (p < 0.01). While Survivin and Survivin-∆Ex3 splice variant expression and localization was identical in serum exosomes, differential expression of Survivin-2B protein existed in the exosomes. Similarly, Survivin and Survivin-∆Ex3 proteins were the predominant forms detected in all of the breast cancer tissues evaluated in this study, whereas a more variable expression of Survivin-2B level was found at different cancer stages.

CONCLUSION

In this study we show for the first time that like Survivin, the Survivin splice variants are also exosomally packaged in the breast cancer patients' sera, mimicking the survivin splice variant pattern that we also report in breast cancer tissues. Differential expression of exosomal-Survivin, particularly Survivin-2B, may serve as a diagnostic and/or prognostic marker, a "liquid biopsy" if you will, in early breast cancer patients. Furthermore, a more thorough understanding of the role of this prominent antiapoptotic pathway could lead to the development of potential therapeutics for breast cancer patients.

Early diagnostic value of survivin and its alternative splice variants in breast cancer

Background

The inhibitor of apoptosis (IAP) protein Survivin and its splice variants are differentially expressed in breast cancer tissues. Our previous work showed Survivin is released from tumor cells via small membrane-bound vesicles called exosomes. We, therefore, hypothesize that analysis of serum exosomal Survivin and its splice variants may provide a novel biomarker for early diagnosis of breast cancer.

Methods

We collected sera from forty breast cancer patients and ten control patients who were disease free for 5 years after treatment. In addition, twenty-three paired breast cancer tumor tissues from those same 40 patients were analyzed for splice variants. Serum levels of Survivin were analyzed using ELISA and exosomes were isolated from this serum using the commercially available ExoQuick kit, with subsequent Western blots and immunohistochemistry performed.

Results

Survivin levels were significantly higher in all the breast cancer samples compared to controls (p < 0.05) with exosome amounts significantly higher in cancer patient sera compared to controls (p < 0.01). While Survivin and Survivin-∆Ex3 splice variant expression and localization was identical in serum exosomes, differential expression of Survivin-2B protein existed in the exosomes. Similarly, Survivin and Survivin-∆Ex3 proteins were the predominant forms detected in all of the breast cancer tissues evaluated in this study, whereas a more variable expression of Survivin-2B level was found at different cancer stages.

Conclusion

In this study we show for the first time that like Survivin, the Survivin splice variants are also exosomally packaged in the breast cancer patients’ sera, mimicking the survivin splice variant pattern that we also report in breast cancer tissues. Differential expression of exosomal-Survivin, particularly Survivin-2B, may serve as a diagnostic and/or prognostic marker, a “liquid biopsy” if you will, in early breast cancer patients. Furthermore, a more thorough understanding of the role of this prominent antiapoptotic pathway could lead to the development of potential therapeutics for breast cancer patients.

Anti-metastatic and anti-tumor growth effects of Origanum majorana on highly metastatic human breast cancer cells: inhibition of NFκB signaling and reduction of nitric oxide production

Background

We have recently reported that Origanummajorana exhibits anticancer activity by promoting cell cycle arrest and apoptosis of the metastatic MDA-MB-231 breast cancer cell line. Here, we extended our study by investigating the effect of O. majorana on the migration, invasion and tumor growth of these cells.

Results

We demonstrate that non-cytotoxic concentrations of O. majorana significantly inhibited the migration and invasion of the MDA-MB-231 cells as shown by wound-healing and matrigel invasion assays. We also show that O. majorana induce homotypic aggregation of MDA-MB-231 associated with an upregulation of E-cadherin protein and promoter activity. Furthermore, we show that O. majorana decrease the adhesion of MDA-MB-231 to HUVECs and inhibits transendothelial migration of MDA-MB-231 through TNF-α-activated HUVECs. Gelatin zymography assay shows that O. majorana suppresses the activities of matrix metalloproteinase-2 and -9 (MMP-2 and MMP-9). ELISA, RT-PCR and Western blot results revealed that O. majorana decreases the expression of MMP-2, MMP-9, urokinase plasminogen activator receptor (uPAR), ICAM-1 and VEGF. Further investigation revealed that O. majorana suppresses the phosphorylation of IκB, downregulates the nuclear level of NFκB and reduces Nitric Oxide (NO) production in MDA-MB-231 cells. Most importantly, by using chick embryo tumor growth assay, we also show that O. majorana promotes inhibition of tumor growth and metastasis in vivo.

Conclusion

Our findings identify Origanummajorana as a promising chemopreventive and therapeutic candidate that modulate breast cancer growth and metastasis.